xref: /openbmc/u-boot/README (revision 493f420e)
1c609719bSwdenk#
2eca3aeb3SWolfgang Denk# (C) Copyright 2000 - 2013
3c609719bSwdenk# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4c609719bSwdenk#
5eca3aeb3SWolfgang Denk# SPDX-License-Identifier:	GPL-2.0+
6c609719bSwdenk#
7c609719bSwdenk
8c609719bSwdenkSummary:
9c609719bSwdenk========
10c609719bSwdenk
1124ee89b9SwdenkThis directory contains the source code for U-Boot, a boot loader for
12e86e5a07SwdenkEmbedded boards based on PowerPC, ARM, MIPS and several other
13e86e5a07Swdenkprocessors, which can be installed in a boot ROM and used to
14e86e5a07Swdenkinitialize and test the hardware or to download and run application
15e86e5a07Swdenkcode.
16c609719bSwdenk
17c609719bSwdenkThe development of U-Boot is closely related to Linux: some parts of
1824ee89b9Swdenkthe source code originate in the Linux source tree, we have some
1924ee89b9Swdenkheader files in common, and special provision has been made to
20c609719bSwdenksupport booting of Linux images.
21c609719bSwdenk
22c609719bSwdenkSome attention has been paid to make this software easily
23c609719bSwdenkconfigurable and extendable. For instance, all monitor commands are
24c609719bSwdenkimplemented with the same call interface, so that it's very easy to
25c609719bSwdenkadd new commands. Also, instead of permanently adding rarely used
26c609719bSwdenkcode (for instance hardware test utilities) to the monitor, you can
27c609719bSwdenkload and run it dynamically.
28c609719bSwdenk
29c609719bSwdenk
30c609719bSwdenkStatus:
31c609719bSwdenk=======
32c609719bSwdenk
33c609719bSwdenkIn general, all boards for which a configuration option exists in the
34c609719bSwdenkMakefile have been tested to some extent and can be considered
35c609719bSwdenk"working". In fact, many of them are used in production systems.
36c609719bSwdenk
377207b366SRobert P. J. DayIn case of problems see the CHANGELOG file to find out who contributed
387207b366SRobert P. J. Daythe specific port. In addition, there are various MAINTAINERS files
397207b366SRobert P. J. Dayscattered throughout the U-Boot source identifying the people or
407207b366SRobert P. J. Daycompanies responsible for various boards and subsystems.
41c609719bSwdenk
427207b366SRobert P. J. DayNote: As of August, 2010, there is no longer a CHANGELOG file in the
437207b366SRobert P. J. Dayactual U-Boot source tree; however, it can be created dynamically
447207b366SRobert P. J. Dayfrom the Git log using:
45adb9d851SRobert P. J. Day
46adb9d851SRobert P. J. Day	make CHANGELOG
47adb9d851SRobert P. J. Day
48c609719bSwdenk
49c609719bSwdenkWhere to get help:
50c609719bSwdenk==================
51c609719bSwdenk
52c609719bSwdenkIn case you have questions about, problems with or contributions for
537207b366SRobert P. J. DayU-Boot, you should send a message to the U-Boot mailing list at
540c32565fSPeter Tyser<u-boot@lists.denx.de>. There is also an archive of previous traffic
550c32565fSPeter Tyseron the mailing list - please search the archive before asking FAQ's.
560c32565fSPeter TyserPlease see http://lists.denx.de/pipermail/u-boot and
570c32565fSPeter Tyserhttp://dir.gmane.org/gmane.comp.boot-loaders.u-boot
58c609719bSwdenk
59c609719bSwdenk
60218ca724SWolfgang DenkWhere to get source code:
61218ca724SWolfgang Denk=========================
62218ca724SWolfgang Denk
637207b366SRobert P. J. DayThe U-Boot source code is maintained in the Git repository at
64218ca724SWolfgang Denkgit://www.denx.de/git/u-boot.git ; you can browse it online at
65218ca724SWolfgang Denkhttp://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
66218ca724SWolfgang Denk
67218ca724SWolfgang DenkThe "snapshot" links on this page allow you to download tarballs of
6811ccc33fSMarcel Ziswilerany version you might be interested in. Official releases are also
69218ca724SWolfgang Denkavailable for FTP download from the ftp://ftp.denx.de/pub/u-boot/
70218ca724SWolfgang Denkdirectory.
71218ca724SWolfgang Denk
72d4ee711dSAnatolij GustschinPre-built (and tested) images are available from
73218ca724SWolfgang Denkftp://ftp.denx.de/pub/u-boot/images/
74218ca724SWolfgang Denk
75218ca724SWolfgang Denk
76c609719bSwdenkWhere we come from:
77c609719bSwdenk===================
78c609719bSwdenk
79c609719bSwdenk- start from 8xxrom sources
8024ee89b9Swdenk- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
81c609719bSwdenk- clean up code
82c609719bSwdenk- make it easier to add custom boards
83c609719bSwdenk- make it possible to add other [PowerPC] CPUs
84c609719bSwdenk- extend functions, especially:
85c609719bSwdenk  * Provide extended interface to Linux boot loader
86c609719bSwdenk  * S-Record download
87c609719bSwdenk  * network boot
8811ccc33fSMarcel Ziswiler  * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
8924ee89b9Swdenk- create ARMBoot project (http://sourceforge.net/projects/armboot)
90c609719bSwdenk- add other CPU families (starting with ARM)
9124ee89b9Swdenk- create U-Boot project (http://sourceforge.net/projects/u-boot)
920d28f34bSMagnus Lilja- current project page: see http://www.denx.de/wiki/U-Boot
9324ee89b9Swdenk
9424ee89b9Swdenk
9524ee89b9SwdenkNames and Spelling:
9624ee89b9Swdenk===================
9724ee89b9Swdenk
9824ee89b9SwdenkThe "official" name of this project is "Das U-Boot". The spelling
9924ee89b9Swdenk"U-Boot" shall be used in all written text (documentation, comments
10024ee89b9Swdenkin source files etc.). Example:
10124ee89b9Swdenk
10224ee89b9Swdenk	This is the README file for the U-Boot project.
10324ee89b9Swdenk
10424ee89b9SwdenkFile names etc. shall be based on the string "u-boot". Examples:
10524ee89b9Swdenk
10624ee89b9Swdenk	include/asm-ppc/u-boot.h
10724ee89b9Swdenk
10824ee89b9Swdenk	#include <asm/u-boot.h>
10924ee89b9Swdenk
11024ee89b9SwdenkVariable names, preprocessor constants etc. shall be either based on
11124ee89b9Swdenkthe string "u_boot" or on "U_BOOT". Example:
11224ee89b9Swdenk
11324ee89b9Swdenk	U_BOOT_VERSION		u_boot_logo
11424ee89b9Swdenk	IH_OS_U_BOOT		u_boot_hush_start
115c609719bSwdenk
116c609719bSwdenk
11793f19cc0SwdenkVersioning:
11893f19cc0Swdenk===========
11993f19cc0Swdenk
120360d883aSThomas WeberStarting with the release in October 2008, the names of the releases
121360d883aSThomas Weberwere changed from numerical release numbers without deeper meaning
122360d883aSThomas Weberinto a time stamp based numbering. Regular releases are identified by
123360d883aSThomas Webernames consisting of the calendar year and month of the release date.
124360d883aSThomas WeberAdditional fields (if present) indicate release candidates or bug fix
125360d883aSThomas Weberreleases in "stable" maintenance trees.
12693f19cc0Swdenk
127360d883aSThomas WeberExamples:
128360d883aSThomas Weber	U-Boot v2009.11	    - Release November 2009
129360d883aSThomas Weber	U-Boot v2009.11.1   - Release 1 in version November 2009 stable tree
1300de21ecbSJelle van der Waa	U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
13193f19cc0Swdenk
13293f19cc0Swdenk
133c609719bSwdenkDirectory Hierarchy:
134c609719bSwdenk====================
135c609719bSwdenk
1368d321b81SPeter Tyser/arch			Architecture specific files
1376eae68e4SMasahiro Yamada  /arc			Files generic to ARC architecture
1388d321b81SPeter Tyser  /arm			Files generic to ARM architecture
1398d321b81SPeter Tyser  /m68k			Files generic to m68k architecture
1408d321b81SPeter Tyser  /microblaze		Files generic to microblaze architecture
1418d321b81SPeter Tyser  /mips			Files generic to MIPS architecture
142afc1ce82SMacpaul Lin  /nds32		Files generic to NDS32 architecture
1438d321b81SPeter Tyser  /nios2		Files generic to Altera NIOS2 architecture
14433c7731bSRobert P. J. Day  /openrisc		Files generic to OpenRISC architecture
145a47a12beSStefan Roese  /powerpc		Files generic to PowerPC architecture
1467207b366SRobert P. J. Day  /sandbox		Files generic to HW-independent "sandbox"
1478d321b81SPeter Tyser  /sh			Files generic to SH architecture
14833c7731bSRobert P. J. Day  /x86			Files generic to x86 architecture
1498d321b81SPeter Tyser/api			Machine/arch independent API for external apps
1508d321b81SPeter Tyser/board			Board dependent files
151740f7e5cSXu Ziyuan/cmd			U-Boot commands functions
1528d321b81SPeter Tyser/common			Misc architecture independent functions
1537207b366SRobert P. J. Day/configs		Board default configuration files
1548d321b81SPeter Tyser/disk			Code for disk drive partition handling
1558d321b81SPeter Tyser/doc			Documentation (don't expect too much)
1568d321b81SPeter Tyser/drivers		Commonly used device drivers
15733c7731bSRobert P. J. Day/dts			Contains Makefile for building internal U-Boot fdt.
1588d321b81SPeter Tyser/examples		Example code for standalone applications, etc.
1598d321b81SPeter Tyser/fs			Filesystem code (cramfs, ext2, jffs2, etc.)
1608d321b81SPeter Tyser/include		Header Files
1617207b366SRobert P. J. Day/lib			Library routines generic to all architectures
1627207b366SRobert P. J. Day/Licenses		Various license files
1638d321b81SPeter Tyser/net			Networking code
1648d321b81SPeter Tyser/post			Power On Self Test
1657207b366SRobert P. J. Day/scripts		Various build scripts and Makefiles
1667207b366SRobert P. J. Day/test			Various unit test files
1678d321b81SPeter Tyser/tools			Tools to build S-Record or U-Boot images, etc.
168c609719bSwdenk
169c609719bSwdenkSoftware Configuration:
170c609719bSwdenk=======================
171c609719bSwdenk
172c609719bSwdenkConfiguration is usually done using C preprocessor defines; the
173c609719bSwdenkrationale behind that is to avoid dead code whenever possible.
174c609719bSwdenk
175c609719bSwdenkThere are two classes of configuration variables:
176c609719bSwdenk
177c609719bSwdenk* Configuration _OPTIONS_:
178c609719bSwdenk  These are selectable by the user and have names beginning with
179c609719bSwdenk  "CONFIG_".
180c609719bSwdenk
181c609719bSwdenk* Configuration _SETTINGS_:
182c609719bSwdenk  These depend on the hardware etc. and should not be meddled with if
183c609719bSwdenk  you don't know what you're doing; they have names beginning with
1846d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  "CONFIG_SYS_".
185c609719bSwdenk
1867207b366SRobert P. J. DayPreviously, all configuration was done by hand, which involved creating
1877207b366SRobert P. J. Daysymbolic links and editing configuration files manually. More recently,
1887207b366SRobert P. J. DayU-Boot has added the Kbuild infrastructure used by the Linux kernel,
1897207b366SRobert P. J. Dayallowing you to use the "make menuconfig" command to configure your
1907207b366SRobert P. J. Daybuild.
191c609719bSwdenk
192c609719bSwdenk
193c609719bSwdenkSelection of Processor Architecture and Board Type:
194c609719bSwdenk---------------------------------------------------
195c609719bSwdenk
196c609719bSwdenkFor all supported boards there are ready-to-use default
197ab584d67SHolger Freytherconfigurations available; just type "make <board_name>_defconfig".
198c609719bSwdenk
199c609719bSwdenkExample: For a TQM823L module type:
200c609719bSwdenk
201c609719bSwdenk	cd u-boot
202ab584d67SHolger Freyther	make TQM823L_defconfig
203c609719bSwdenk
2047207b366SRobert P. J. DayNote: If you're looking for the default configuration file for a board
2057207b366SRobert P. J. Dayyou're sure used to be there but is now missing, check the file
2067207b366SRobert P. J. Daydoc/README.scrapyard for a list of no longer supported boards.
207c609719bSwdenk
20875b3c3aaSSimon GlassSandbox Environment:
20975b3c3aaSSimon Glass--------------------
21075b3c3aaSSimon Glass
21175b3c3aaSSimon GlassU-Boot can be built natively to run on a Linux host using the 'sandbox'
21275b3c3aaSSimon Glassboard. This allows feature development which is not board- or architecture-
21375b3c3aaSSimon Glassspecific to be undertaken on a native platform. The sandbox is also used to
21475b3c3aaSSimon Glassrun some of U-Boot's tests.
21575b3c3aaSSimon Glass
2166b1978f8SJagannadha Sutradharudu TekiSee board/sandbox/README.sandbox for more details.
21775b3c3aaSSimon Glass
21875b3c3aaSSimon Glass
219db910353SSimon GlassBoard Initialisation Flow:
220db910353SSimon Glass--------------------------
221db910353SSimon Glass
222db910353SSimon GlassThis is the intended start-up flow for boards. This should apply for both
2237207b366SRobert P. J. DaySPL and U-Boot proper (i.e. they both follow the same rules).
224db910353SSimon Glass
2257207b366SRobert P. J. DayNote: "SPL" stands for "Secondary Program Loader," which is explained in
2267207b366SRobert P. J. Daymore detail later in this file.
2277207b366SRobert P. J. Day
2287207b366SRobert P. J. DayAt present, SPL mostly uses a separate code path, but the function names
2297207b366SRobert P. J. Dayand roles of each function are the same. Some boards or architectures
2307207b366SRobert P. J. Daymay not conform to this.  At least most ARM boards which use
2317207b366SRobert P. J. DayCONFIG_SPL_FRAMEWORK conform to this.
2327207b366SRobert P. J. Day
2337207b366SRobert P. J. DayExecution typically starts with an architecture-specific (and possibly
2347207b366SRobert P. J. DayCPU-specific) start.S file, such as:
2357207b366SRobert P. J. Day
2367207b366SRobert P. J. Day	- arch/arm/cpu/armv7/start.S
2377207b366SRobert P. J. Day	- arch/powerpc/cpu/mpc83xx/start.S
2387207b366SRobert P. J. Day	- arch/mips/cpu/start.S
2397207b366SRobert P. J. Day
2407207b366SRobert P. J. Dayand so on. From there, three functions are called; the purpose and
2417207b366SRobert P. J. Daylimitations of each of these functions are described below.
242db910353SSimon Glass
243db910353SSimon Glasslowlevel_init():
244db910353SSimon Glass	- purpose: essential init to permit execution to reach board_init_f()
245db910353SSimon Glass	- no global_data or BSS
246db910353SSimon Glass	- there is no stack (ARMv7 may have one but it will soon be removed)
247db910353SSimon Glass	- must not set up SDRAM or use console
248db910353SSimon Glass	- must only do the bare minimum to allow execution to continue to
249db910353SSimon Glass		board_init_f()
250db910353SSimon Glass	- this is almost never needed
251db910353SSimon Glass	- return normally from this function
252db910353SSimon Glass
253db910353SSimon Glassboard_init_f():
254db910353SSimon Glass	- purpose: set up the machine ready for running board_init_r():
255db910353SSimon Glass		i.e. SDRAM and serial UART
256db910353SSimon Glass	- global_data is available
257db910353SSimon Glass	- stack is in SRAM
258db910353SSimon Glass	- BSS is not available, so you cannot use global/static variables,
259db910353SSimon Glass		only stack variables and global_data
260db910353SSimon Glass
261db910353SSimon Glass	Non-SPL-specific notes:
262db910353SSimon Glass	- dram_init() is called to set up DRAM. If already done in SPL this
263db910353SSimon Glass		can do nothing
264db910353SSimon Glass
265db910353SSimon Glass	SPL-specific notes:
266db910353SSimon Glass	- you can override the entire board_init_f() function with your own
267db910353SSimon Glass		version as needed.
268db910353SSimon Glass	- preloader_console_init() can be called here in extremis
269db910353SSimon Glass	- should set up SDRAM, and anything needed to make the UART work
270db910353SSimon Glass	- these is no need to clear BSS, it will be done by crt0.S
271db910353SSimon Glass	- must return normally from this function (don't call board_init_r()
272db910353SSimon Glass		directly)
273db910353SSimon Glass
274db910353SSimon GlassHere the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
275db910353SSimon Glassthis point the stack and global_data are relocated to below
276db910353SSimon GlassCONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
277db910353SSimon Glassmemory.
278db910353SSimon Glass
279db910353SSimon Glassboard_init_r():
280db910353SSimon Glass	- purpose: main execution, common code
281db910353SSimon Glass	- global_data is available
282db910353SSimon Glass	- SDRAM is available
283db910353SSimon Glass	- BSS is available, all static/global variables can be used
284db910353SSimon Glass	- execution eventually continues to main_loop()
285db910353SSimon Glass
286db910353SSimon Glass	Non-SPL-specific notes:
287db910353SSimon Glass	- U-Boot is relocated to the top of memory and is now running from
288db910353SSimon Glass		there.
289db910353SSimon Glass
290db910353SSimon Glass	SPL-specific notes:
291db910353SSimon Glass	- stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
292db910353SSimon Glass		CONFIG_SPL_STACK_R_ADDR points into SDRAM
293db910353SSimon Glass	- preloader_console_init() can be called here - typically this is
2940680f1b1SLey Foon Tan		done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
295db910353SSimon Glass		spl_board_init() function containing this call
296db910353SSimon Glass	- loads U-Boot or (in falcon mode) Linux
297db910353SSimon Glass
298db910353SSimon Glass
299db910353SSimon Glass
300c609719bSwdenkConfiguration Options:
301c609719bSwdenk----------------------
302c609719bSwdenk
303c609719bSwdenkConfiguration depends on the combination of board and CPU type; all
304c609719bSwdenksuch information is kept in a configuration file
305c609719bSwdenk"include/configs/<board_name>.h".
306c609719bSwdenk
307c609719bSwdenkExample: For a TQM823L module, all configuration settings are in
308c609719bSwdenk"include/configs/TQM823L.h".
309c609719bSwdenk
310c609719bSwdenk
3117f6c2cbcSwdenkMany of the options are named exactly as the corresponding Linux
3127f6c2cbcSwdenkkernel configuration options. The intention is to make it easier to
3137f6c2cbcSwdenkbuild a config tool - later.
3147f6c2cbcSwdenk
3157f6c2cbcSwdenk
316c609719bSwdenkThe following options need to be configured:
317c609719bSwdenk
3182628114eSKim Phillips- CPU Type:	Define exactly one, e.g. CONFIG_MPC85XX.
319c609719bSwdenk
3202628114eSKim Phillips- Board Type:	Define exactly one, e.g. CONFIG_MPC8540ADS.
3216ccec449SWolfgang Denk
322cf946c6dSLei Wen- Marvell Family Member
323cf946c6dSLei Wen		CONFIG_SYS_MVFS		- define it if you want to enable
324cf946c6dSLei Wen					  multiple fs option at one time
325cf946c6dSLei Wen					  for marvell soc family
326cf946c6dSLei Wen
32766412c63SKumar Gala- 85xx CPU Options:
328ffd06e02SYork Sun		CONFIG_SYS_PPC64
329ffd06e02SYork Sun
330ffd06e02SYork Sun		Specifies that the core is a 64-bit PowerPC implementation (implements
331ffd06e02SYork Sun		the "64" category of the Power ISA). This is necessary for ePAPR
332ffd06e02SYork Sun		compliance, among other possible reasons.
333ffd06e02SYork Sun
33466412c63SKumar Gala		CONFIG_SYS_FSL_TBCLK_DIV
33566412c63SKumar Gala
33666412c63SKumar Gala		Defines the core time base clock divider ratio compared to the
33766412c63SKumar Gala		system clock.  On most PQ3 devices this is 8, on newer QorIQ
33866412c63SKumar Gala		devices it can be 16 or 32.  The ratio varies from SoC to Soc.
33966412c63SKumar Gala
3408f29084aSKumar Gala		CONFIG_SYS_FSL_PCIE_COMPAT
3418f29084aSKumar Gala
3428f29084aSKumar Gala		Defines the string to utilize when trying to match PCIe device
3438f29084aSKumar Gala		tree nodes for the given platform.
3448f29084aSKumar Gala
34533eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510
34633eee330SScott Wood
34733eee330SScott Wood		Enables a workaround for erratum A004510.  If set,
34833eee330SScott Wood		then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
34933eee330SScott Wood		CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
35033eee330SScott Wood
35133eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
35233eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
35333eee330SScott Wood
35433eee330SScott Wood		Defines one or two SoC revisions (low 8 bits of SVR)
35533eee330SScott Wood		for which the A004510 workaround should be applied.
35633eee330SScott Wood
35733eee330SScott Wood		The rest of SVR is either not relevant to the decision
35833eee330SScott Wood		of whether the erratum is present (e.g. p2040 versus
35933eee330SScott Wood		p2041) or is implied by the build target, which controls
36033eee330SScott Wood		whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
36133eee330SScott Wood
36233eee330SScott Wood		See Freescale App Note 4493 for more information about
36333eee330SScott Wood		this erratum.
36433eee330SScott Wood
36574fa22edSPrabhakar Kushwaha		CONFIG_A003399_NOR_WORKAROUND
36674fa22edSPrabhakar Kushwaha		Enables a workaround for IFC erratum A003399. It is only
367b445bbb4SJeremiah Mahler		required during NOR boot.
36874fa22edSPrabhakar Kushwaha
3699f074e67SPrabhakar Kushwaha		CONFIG_A008044_WORKAROUND
3709f074e67SPrabhakar Kushwaha		Enables a workaround for T1040/T1042 erratum A008044. It is only
371b445bbb4SJeremiah Mahler		required during NAND boot and valid for Rev 1.0 SoC revision
3729f074e67SPrabhakar Kushwaha
37333eee330SScott Wood		CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
37433eee330SScott Wood
37533eee330SScott Wood		This is the value to write into CCSR offset 0x18600
37633eee330SScott Wood		according to the A004510 workaround.
37733eee330SScott Wood
37864501c66SPriyanka Jain		CONFIG_SYS_FSL_DSP_DDR_ADDR
37964501c66SPriyanka Jain		This value denotes start offset of DDR memory which is
38064501c66SPriyanka Jain		connected exclusively to the DSP cores.
38164501c66SPriyanka Jain
382765b0bdbSPriyanka Jain		CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
383765b0bdbSPriyanka Jain		This value denotes start offset of M2 memory
384765b0bdbSPriyanka Jain		which is directly connected to the DSP core.
385765b0bdbSPriyanka Jain
38664501c66SPriyanka Jain		CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
38764501c66SPriyanka Jain		This value denotes start offset of M3 memory which is directly
38864501c66SPriyanka Jain		connected to the DSP core.
38964501c66SPriyanka Jain
390765b0bdbSPriyanka Jain		CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
391765b0bdbSPriyanka Jain		This value denotes start offset of DSP CCSR space.
392765b0bdbSPriyanka Jain
393b135991aSPriyanka Jain		CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
394b135991aSPriyanka Jain		Single Source Clock is clocking mode present in some of FSL SoC's.
395b135991aSPriyanka Jain		In this mode, a single differential clock is used to supply
396b135991aSPriyanka Jain		clocks to the sysclock, ddrclock and usbclock.
397b135991aSPriyanka Jain
398fb4a2409SAneesh Bansal		CONFIG_SYS_CPC_REINIT_F
399fb4a2409SAneesh Bansal		This CONFIG is defined when the CPC is configured as SRAM at the
400a187559eSBin Meng		time of U-Boot entry and is required to be re-initialized.
401fb4a2409SAneesh Bansal
402aade2004STang Yuantian		CONFIG_DEEP_SLEEP
403b445bbb4SJeremiah Mahler		Indicates this SoC supports deep sleep feature. If deep sleep is
404aade2004STang Yuantian		supported, core will start to execute uboot when wakes up.
405aade2004STang Yuantian
4066cb461b4SDaniel Schwierzeck- Generic CPU options:
4072a1680e3SYork Sun		CONFIG_SYS_GENERIC_GLOBAL_DATA
4082a1680e3SYork Sun		Defines global data is initialized in generic board board_init_f().
4092a1680e3SYork Sun		If this macro is defined, global data is created and cleared in
4102a1680e3SYork Sun		generic board board_init_f(). Without this macro, architecture/board
4112a1680e3SYork Sun		should initialize global data before calling board_init_f().
4122a1680e3SYork Sun
4136cb461b4SDaniel Schwierzeck		CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
4146cb461b4SDaniel Schwierzeck
4156cb461b4SDaniel Schwierzeck		Defines the endianess of the CPU. Implementation of those
4166cb461b4SDaniel Schwierzeck		values is arch specific.
4176cb461b4SDaniel Schwierzeck
4185614e71bSYork Sun		CONFIG_SYS_FSL_DDR
4195614e71bSYork Sun		Freescale DDR driver in use. This type of DDR controller is
4205614e71bSYork Sun		found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
4215614e71bSYork Sun		SoCs.
4225614e71bSYork Sun
4235614e71bSYork Sun		CONFIG_SYS_FSL_DDR_ADDR
4245614e71bSYork Sun		Freescale DDR memory-mapped register base.
4255614e71bSYork Sun
4265614e71bSYork Sun		CONFIG_SYS_FSL_DDR_EMU
4275614e71bSYork Sun		Specify emulator support for DDR. Some DDR features such as
4285614e71bSYork Sun		deskew training are not available.
4295614e71bSYork Sun
4305614e71bSYork Sun		CONFIG_SYS_FSL_DDRC_GEN1
4315614e71bSYork Sun		Freescale DDR1 controller.
4325614e71bSYork Sun
4335614e71bSYork Sun		CONFIG_SYS_FSL_DDRC_GEN2
4345614e71bSYork Sun		Freescale DDR2 controller.
4355614e71bSYork Sun
4365614e71bSYork Sun		CONFIG_SYS_FSL_DDRC_GEN3
4375614e71bSYork Sun		Freescale DDR3 controller.
4385614e71bSYork Sun
43934e026f9SYork Sun		CONFIG_SYS_FSL_DDRC_GEN4
44034e026f9SYork Sun		Freescale DDR4 controller.
44134e026f9SYork Sun
4429ac4ffbdSYork Sun		CONFIG_SYS_FSL_DDRC_ARM_GEN3
4439ac4ffbdSYork Sun		Freescale DDR3 controller for ARM-based SoCs.
4449ac4ffbdSYork Sun
4455614e71bSYork Sun		CONFIG_SYS_FSL_DDR1
4465614e71bSYork Sun		Board config to use DDR1. It can be enabled for SoCs with
4475614e71bSYork Sun		Freescale DDR1 or DDR2 controllers, depending on the board
4485614e71bSYork Sun		implemetation.
4495614e71bSYork Sun
4505614e71bSYork Sun		CONFIG_SYS_FSL_DDR2
45162a3b7ddSRobert P. J. Day		Board config to use DDR2. It can be enabled for SoCs with
4525614e71bSYork Sun		Freescale DDR2 or DDR3 controllers, depending on the board
4535614e71bSYork Sun		implementation.
4545614e71bSYork Sun
4555614e71bSYork Sun		CONFIG_SYS_FSL_DDR3
4565614e71bSYork Sun		Board config to use DDR3. It can be enabled for SoCs with
45734e026f9SYork Sun		Freescale DDR3 or DDR3L controllers.
45834e026f9SYork Sun
45934e026f9SYork Sun		CONFIG_SYS_FSL_DDR3L
46034e026f9SYork Sun		Board config to use DDR3L. It can be enabled for SoCs with
46134e026f9SYork Sun		DDR3L controllers.
46234e026f9SYork Sun
46334e026f9SYork Sun		CONFIG_SYS_FSL_DDR4
46434e026f9SYork Sun		Board config to use DDR4. It can be enabled for SoCs with
46534e026f9SYork Sun		DDR4 controllers.
4665614e71bSYork Sun
4671b4175d6SPrabhakar Kushwaha		CONFIG_SYS_FSL_IFC_BE
4681b4175d6SPrabhakar Kushwaha		Defines the IFC controller register space as Big Endian
4691b4175d6SPrabhakar Kushwaha
4701b4175d6SPrabhakar Kushwaha		CONFIG_SYS_FSL_IFC_LE
4711b4175d6SPrabhakar Kushwaha		Defines the IFC controller register space as Little Endian
4721b4175d6SPrabhakar Kushwaha
4731c40707eSPrabhakar Kushwaha		CONFIG_SYS_FSL_IFC_CLK_DIV
4741c40707eSPrabhakar Kushwaha		Defines divider of platform clock(clock input to IFC controller).
4751c40707eSPrabhakar Kushwaha
476add63f94SPrabhakar Kushwaha		CONFIG_SYS_FSL_LBC_CLK_DIV
477add63f94SPrabhakar Kushwaha		Defines divider of platform clock(clock input to eLBC controller).
478add63f94SPrabhakar Kushwaha
479690e4258SPrabhakar Kushwaha		CONFIG_SYS_FSL_PBL_PBI
480690e4258SPrabhakar Kushwaha		It enables addition of RCW (Power on reset configuration) in built image.
481690e4258SPrabhakar Kushwaha		Please refer doc/README.pblimage for more details
482690e4258SPrabhakar Kushwaha
483690e4258SPrabhakar Kushwaha		CONFIG_SYS_FSL_PBL_RCW
484690e4258SPrabhakar Kushwaha		It adds PBI(pre-boot instructions) commands in u-boot build image.
485690e4258SPrabhakar Kushwaha		PBI commands can be used to configure SoC before it starts the execution.
486690e4258SPrabhakar Kushwaha		Please refer doc/README.pblimage for more details
487690e4258SPrabhakar Kushwaha
48889ad7be8SPrabhakar Kushwaha		CONFIG_SPL_FSL_PBL
48989ad7be8SPrabhakar Kushwaha		It adds a target to create boot binary having SPL binary in PBI format
49089ad7be8SPrabhakar Kushwaha		concatenated with u-boot binary.
49189ad7be8SPrabhakar Kushwaha
4924e5b1bd0SYork Sun		CONFIG_SYS_FSL_DDR_BE
4934e5b1bd0SYork Sun		Defines the DDR controller register space as Big Endian
4944e5b1bd0SYork Sun
4954e5b1bd0SYork Sun		CONFIG_SYS_FSL_DDR_LE
4964e5b1bd0SYork Sun		Defines the DDR controller register space as Little Endian
4974e5b1bd0SYork Sun
4986b9e309aSYork Sun		CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
4996b9e309aSYork Sun		Physical address from the view of DDR controllers. It is the
5006b9e309aSYork Sun		same as CONFIG_SYS_DDR_SDRAM_BASE for  all Power SoCs. But
5016b9e309aSYork Sun		it could be different for ARM SoCs.
5026b9e309aSYork Sun
5036b1e1254SYork Sun		CONFIG_SYS_FSL_DDR_INTLV_256B
5046b1e1254SYork Sun		DDR controller interleaving on 256-byte. This is a special
5056b1e1254SYork Sun		interleaving mode, handled by Dickens for Freescale layerscape
5066b1e1254SYork Sun		SoCs with ARM core.
5076b1e1254SYork Sun
5081d71efbbSYork Sun		CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
5091d71efbbSYork Sun		Number of controllers used as main memory.
5101d71efbbSYork Sun
5111d71efbbSYork Sun		CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
5121d71efbbSYork Sun		Number of controllers used for other than main memory.
5131d71efbbSYork Sun
51444937214SPrabhakar Kushwaha		CONFIG_SYS_FSL_HAS_DP_DDR
51544937214SPrabhakar Kushwaha		Defines the SoC has DP-DDR used for DPAA.
51644937214SPrabhakar Kushwaha
517028dbb8dSRuchika Gupta		CONFIG_SYS_FSL_SEC_BE
518028dbb8dSRuchika Gupta		Defines the SEC controller register space as Big Endian
519028dbb8dSRuchika Gupta
520028dbb8dSRuchika Gupta		CONFIG_SYS_FSL_SEC_LE
521028dbb8dSRuchika Gupta		Defines the SEC controller register space as Little Endian
522028dbb8dSRuchika Gupta
52392bbd64eSDaniel Schwierzeck- MIPS CPU options:
52492bbd64eSDaniel Schwierzeck		CONFIG_SYS_INIT_SP_OFFSET
52592bbd64eSDaniel Schwierzeck
52692bbd64eSDaniel Schwierzeck		Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
52792bbd64eSDaniel Schwierzeck		pointer. This is needed for the temporary stack before
52892bbd64eSDaniel Schwierzeck		relocation.
52992bbd64eSDaniel Schwierzeck
53092bbd64eSDaniel Schwierzeck		CONFIG_SYS_MIPS_CACHE_MODE
53192bbd64eSDaniel Schwierzeck
53292bbd64eSDaniel Schwierzeck		Cache operation mode for the MIPS CPU.
53392bbd64eSDaniel Schwierzeck		See also arch/mips/include/asm/mipsregs.h.
53492bbd64eSDaniel Schwierzeck		Possible values are:
53592bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_NO_WA
53692bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_WA
53792bbd64eSDaniel Schwierzeck			CONF_CM_UNCACHED
53892bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_NONCOHERENT
53992bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_CE
54092bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_COW
54192bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_CUW
54292bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_ACCELERATED
54392bbd64eSDaniel Schwierzeck
54492bbd64eSDaniel Schwierzeck		CONFIG_SYS_XWAY_EBU_BOOTCFG
54592bbd64eSDaniel Schwierzeck
54692bbd64eSDaniel Schwierzeck		Special option for Lantiq XWAY SoCs for booting from NOR flash.
54792bbd64eSDaniel Schwierzeck		See also arch/mips/cpu/mips32/start.S.
54892bbd64eSDaniel Schwierzeck
54992bbd64eSDaniel Schwierzeck		CONFIG_XWAY_SWAP_BYTES
55092bbd64eSDaniel Schwierzeck
55192bbd64eSDaniel Schwierzeck		Enable compilation of tools/xway-swap-bytes needed for Lantiq
55292bbd64eSDaniel Schwierzeck		XWAY SoCs for booting from NOR flash. The U-Boot image needs to
55392bbd64eSDaniel Schwierzeck		be swapped if a flash programmer is used.
55492bbd64eSDaniel Schwierzeck
555b67d8816SChristian Riesch- ARM options:
556b67d8816SChristian Riesch		CONFIG_SYS_EXCEPTION_VECTORS_HIGH
557b67d8816SChristian Riesch
558b67d8816SChristian Riesch		Select high exception vectors of the ARM core, e.g., do not
559b67d8816SChristian Riesch		clear the V bit of the c1 register of CP15.
560b67d8816SChristian Riesch
561207774b2SYork Sun		COUNTER_FREQUENCY
562207774b2SYork Sun		Generic timer clock source frequency.
563207774b2SYork Sun
564207774b2SYork Sun		COUNTER_FREQUENCY_REAL
565207774b2SYork Sun		Generic timer clock source frequency if the real clock is
566207774b2SYork Sun		different from COUNTER_FREQUENCY, and can only be determined
567207774b2SYork Sun		at run time.
568207774b2SYork Sun
56973c38934SStephen Warren- Tegra SoC options:
57073c38934SStephen Warren		CONFIG_TEGRA_SUPPORT_NON_SECURE
57173c38934SStephen Warren
57273c38934SStephen Warren		Support executing U-Boot in non-secure (NS) mode. Certain
57373c38934SStephen Warren		impossible actions will be skipped if the CPU is in NS mode,
57473c38934SStephen Warren		such as ARM architectural timer initialization.
57573c38934SStephen Warren
5765da627a4Swdenk- Linux Kernel Interface:
577c609719bSwdenk		CONFIG_CLOCKS_IN_MHZ
578c609719bSwdenk
579c609719bSwdenk		U-Boot stores all clock information in Hz
580c609719bSwdenk		internally. For binary compatibility with older Linux
581c609719bSwdenk		kernels (which expect the clocks passed in the
582c609719bSwdenk		bd_info data to be in MHz) the environment variable
583c609719bSwdenk		"clocks_in_mhz" can be defined so that U-Boot
584c609719bSwdenk		converts clock data to MHZ before passing it to the
585c609719bSwdenk		Linux kernel.
586c609719bSwdenk		When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
587c609719bSwdenk		"clocks_in_mhz=1" is automatically included in the
588c609719bSwdenk		default environment.
589c609719bSwdenk
5905da627a4Swdenk		CONFIG_MEMSIZE_IN_BYTES		[relevant for MIPS only]
5915da627a4Swdenk
592b445bbb4SJeremiah Mahler		When transferring memsize parameter to Linux, some versions
5935da627a4Swdenk		expect it to be in bytes, others in MB.
5945da627a4Swdenk		Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
5955da627a4Swdenk
596fec6d9eeSGerald Van Baren		CONFIG_OF_LIBFDT
597f57f70aaSWolfgang Denk
598f57f70aaSWolfgang Denk		New kernel versions are expecting firmware settings to be
599213bf8c8SGerald Van Baren		passed using flattened device trees (based on open firmware
600213bf8c8SGerald Van Baren		concepts).
601213bf8c8SGerald Van Baren
602213bf8c8SGerald Van Baren		CONFIG_OF_LIBFDT
603213bf8c8SGerald Van Baren		 * New libfdt-based support
604213bf8c8SGerald Van Baren		 * Adds the "fdt" command
6053bb342fcSKim Phillips		 * The bootm command automatically updates the fdt
606213bf8c8SGerald Van Baren
607f57f70aaSWolfgang Denk		OF_TBCLK - The timebase frequency.
608c2871f03SKumar Gala		OF_STDOUT_PATH - The path to the console device
609f57f70aaSWolfgang Denk
61011ccc33fSMarcel Ziswiler		boards with QUICC Engines require OF_QE to set UCC MAC
61111ccc33fSMarcel Ziswiler		addresses
6123bb342fcSKim Phillips
6134e253137SKumar Gala		CONFIG_OF_BOARD_SETUP
6144e253137SKumar Gala
6154e253137SKumar Gala		Board code has addition modification that it wants to make
6164e253137SKumar Gala		to the flat device tree before handing it off to the kernel
6176705d81eSwdenk
618c654b517SSimon Glass		CONFIG_OF_SYSTEM_SETUP
619c654b517SSimon Glass
620c654b517SSimon Glass		Other code has addition modification that it wants to make
621c654b517SSimon Glass		to the flat device tree before handing it off to the kernel.
622c654b517SSimon Glass		This causes ft_system_setup() to be called before booting
623c654b517SSimon Glass		the kernel.
624c654b517SSimon Glass
6253887c3fbSHeiko Schocher		CONFIG_OF_IDE_FIXUP
6263887c3fbSHeiko Schocher
6273887c3fbSHeiko Schocher		U-Boot can detect if an IDE device is present or not.
6283887c3fbSHeiko Schocher		If not, and this new config option is activated, U-Boot
6293887c3fbSHeiko Schocher		removes the ATA node from the DTS before booting Linux,
6303887c3fbSHeiko Schocher		so the Linux IDE driver does not probe the device and
6313887c3fbSHeiko Schocher		crash. This is needed for buggy hardware (uc101) where
6323887c3fbSHeiko Schocher		no pull down resistor is connected to the signal IDE5V_DD7.
6333887c3fbSHeiko Schocher
6347eb29398SIgor Grinberg		CONFIG_MACH_TYPE	[relevant for ARM only][mandatory]
6357eb29398SIgor Grinberg
6367eb29398SIgor Grinberg		This setting is mandatory for all boards that have only one
6377eb29398SIgor Grinberg		machine type and must be used to specify the machine type
6387eb29398SIgor Grinberg		number as it appears in the ARM machine registry
6397eb29398SIgor Grinberg		(see http://www.arm.linux.org.uk/developer/machines/).
6407eb29398SIgor Grinberg		Only boards that have multiple machine types supported
6417eb29398SIgor Grinberg		in a single configuration file and the machine type is
6427eb29398SIgor Grinberg		runtime discoverable, do not have to use this setting.
6437eb29398SIgor Grinberg
6440b2f4ecaSNiklaus Giger- vxWorks boot parameters:
6450b2f4ecaSNiklaus Giger
6460b2f4ecaSNiklaus Giger		bootvx constructs a valid bootline using the following
6479e98b7e3SBin Meng		environments variables: bootdev, bootfile, ipaddr, netmask,
6489e98b7e3SBin Meng		serverip, gatewayip, hostname, othbootargs.
6490b2f4ecaSNiklaus Giger		It loads the vxWorks image pointed bootfile.
6500b2f4ecaSNiklaus Giger
6510b2f4ecaSNiklaus Giger		Note: If a "bootargs" environment is defined, it will overwride
6520b2f4ecaSNiklaus Giger		the defaults discussed just above.
6530b2f4ecaSNiklaus Giger
6542c451f78SAneesh V- Cache Configuration:
6552c451f78SAneesh V		CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
6562c451f78SAneesh V		CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
6572c451f78SAneesh V		CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
6582c451f78SAneesh V
65993bc2193SAneesh V- Cache Configuration for ARM:
66093bc2193SAneesh V		CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
66193bc2193SAneesh V				      controller
66293bc2193SAneesh V		CONFIG_SYS_PL310_BASE - Physical base address of PL310
66393bc2193SAneesh V					controller register space
66493bc2193SAneesh V
6656705d81eSwdenk- Serial Ports:
66648d0192fSAndreas Engel		CONFIG_PL010_SERIAL
6676705d81eSwdenk
6686705d81eSwdenk		Define this if you want support for Amba PrimeCell PL010 UARTs.
6696705d81eSwdenk
67048d0192fSAndreas Engel		CONFIG_PL011_SERIAL
6716705d81eSwdenk
6726705d81eSwdenk		Define this if you want support for Amba PrimeCell PL011 UARTs.
6736705d81eSwdenk
6746705d81eSwdenk		CONFIG_PL011_CLOCK
6756705d81eSwdenk
6766705d81eSwdenk		If you have Amba PrimeCell PL011 UARTs, set this variable to
6776705d81eSwdenk		the clock speed of the UARTs.
6786705d81eSwdenk
6796705d81eSwdenk		CONFIG_PL01x_PORTS
6806705d81eSwdenk
6816705d81eSwdenk		If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
6826705d81eSwdenk		define this to a list of base addresses for each (supported)
6836705d81eSwdenk		port. See e.g. include/configs/versatile.h
6846705d81eSwdenk
685d57dee57SKaricheri, Muralidharan		CONFIG_SERIAL_HW_FLOW_CONTROL
686d57dee57SKaricheri, Muralidharan
687d57dee57SKaricheri, Muralidharan		Define this variable to enable hw flow control in serial driver.
688d57dee57SKaricheri, Muralidharan		Current user of this option is drivers/serial/nsl16550.c driver
6896705d81eSwdenk
690c609719bSwdenk- Console Baudrate:
691c609719bSwdenk		CONFIG_BAUDRATE - in bps
692c609719bSwdenk		Select one of the baudrates listed in
6936d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_BAUDRATE_TABLE, see below.
694c609719bSwdenk
695c609719bSwdenk- Autoboot Command:
696c609719bSwdenk		CONFIG_BOOTCOMMAND
697c609719bSwdenk		Only needed when CONFIG_BOOTDELAY is enabled;
698c609719bSwdenk		define a command string that is automatically executed
699c609719bSwdenk		when no character is read on the console interface
700c609719bSwdenk		within "Boot Delay" after reset.
701c609719bSwdenk
702c609719bSwdenk		CONFIG_BOOTARGS
703c609719bSwdenk		This can be used to pass arguments to the bootm
704c609719bSwdenk		command. The value of CONFIG_BOOTARGS goes into the
705c609719bSwdenk		environment value "bootargs".
706c609719bSwdenk
707c609719bSwdenk		CONFIG_RAMBOOT and CONFIG_NFSBOOT
708c609719bSwdenk		The value of these goes into the environment as
709c609719bSwdenk		"ramboot" and "nfsboot" respectively, and can be used
710c609719bSwdenk		as a convenience, when switching between booting from
71111ccc33fSMarcel Ziswiler		RAM and NFS.
712c609719bSwdenk
713eda0ba38SHeiko Schocher- Bootcount:
714eda0ba38SHeiko Schocher		CONFIG_BOOTCOUNT_LIMIT
715eda0ba38SHeiko Schocher		Implements a mechanism for detecting a repeating reboot
716eda0ba38SHeiko Schocher		cycle, see:
717eda0ba38SHeiko Schocher		http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
718eda0ba38SHeiko Schocher
719eda0ba38SHeiko Schocher		CONFIG_BOOTCOUNT_ENV
720eda0ba38SHeiko Schocher		If no softreset save registers are found on the hardware
721eda0ba38SHeiko Schocher		"bootcount" is stored in the environment. To prevent a
722eda0ba38SHeiko Schocher		saveenv on all reboots, the environment variable
723eda0ba38SHeiko Schocher		"upgrade_available" is used. If "upgrade_available" is
724eda0ba38SHeiko Schocher		0, "bootcount" is always 0, if "upgrade_available" is
725eda0ba38SHeiko Schocher		1 "bootcount" is incremented in the environment.
726eda0ba38SHeiko Schocher		So the Userspace Applikation must set the "upgrade_available"
727eda0ba38SHeiko Schocher		and "bootcount" variable to 0, if a boot was successfully.
728eda0ba38SHeiko Schocher
729c609719bSwdenk- Pre-Boot Commands:
730c609719bSwdenk		CONFIG_PREBOOT
731c609719bSwdenk
732c609719bSwdenk		When this option is #defined, the existence of the
733c609719bSwdenk		environment variable "preboot" will be checked
734c609719bSwdenk		immediately before starting the CONFIG_BOOTDELAY
735c609719bSwdenk		countdown and/or running the auto-boot command resp.
736c609719bSwdenk		entering interactive mode.
737c609719bSwdenk
738c609719bSwdenk		This feature is especially useful when "preboot" is
739c609719bSwdenk		automatically generated or modified. For an example
740c609719bSwdenk		see the LWMON board specific code: here "preboot" is
741c609719bSwdenk		modified when the user holds down a certain
742c609719bSwdenk		combination of keys on the (special) keyboard when
743c609719bSwdenk		booting the systems
744c609719bSwdenk
745c609719bSwdenk- Serial Download Echo Mode:
746c609719bSwdenk		CONFIG_LOADS_ECHO
747c609719bSwdenk		If defined to 1, all characters received during a
748c609719bSwdenk		serial download (using the "loads" command) are
749c609719bSwdenk		echoed back. This might be needed by some terminal
750c609719bSwdenk		emulations (like "cu"), but may as well just take
751c609719bSwdenk		time on others. This setting #define's the initial
752c609719bSwdenk		value of the "loads_echo" environment variable.
753c609719bSwdenk
754602ad3b3SJon Loeliger- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
755c609719bSwdenk		CONFIG_KGDB_BAUDRATE
756c609719bSwdenk		Select one of the baudrates listed in
7576d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_BAUDRATE_TABLE, see below.
758c609719bSwdenk
759c609719bSwdenk- Monitor Functions:
760602ad3b3SJon Loeliger		Monitor commands can be included or excluded
761602ad3b3SJon Loeliger		from the build by using the #include files
762c6c621bdSStephen Warren		<config_cmd_all.h> and #undef'ing unwanted
763ef0f2f57SJoe Hershberger		commands, or adding #define's for wanted commands.
764c609719bSwdenk
765602ad3b3SJon Loeliger		The default command configuration includes all commands
766602ad3b3SJon Loeliger		except those marked below with a "*".
767602ad3b3SJon Loeliger
768b401b73dSMarek Vasut		CONFIG_CMD_AES		  AES 128 CBC encrypt/decrypt
769602ad3b3SJon Loeliger		CONFIG_CMD_ASKENV	* ask for env variable
770602ad3b3SJon Loeliger		CONFIG_CMD_BDI		  bdinfo
771602ad3b3SJon Loeliger		CONFIG_CMD_BOOTD	  bootd
772d2b2ffe3STom Rini		CONFIG_CMD_BOOTI	* ARM64 Linux kernel Image support
773602ad3b3SJon Loeliger		CONFIG_CMD_CACHE	* icache, dcache
774602ad3b3SJon Loeliger		CONFIG_CMD_CONSOLE	  coninfo
775602ad3b3SJon Loeliger		CONFIG_CMD_DHCP		* DHCP support
776602ad3b3SJon Loeliger		CONFIG_CMD_DIAG		* Diagnostics
777602ad3b3SJon Loeliger		CONFIG_CMD_ECHO		  echo arguments
778246c6922SPeter Tyser		CONFIG_CMD_EDITENV	  edit env variable
779602ad3b3SJon Loeliger		CONFIG_CMD_ELF		* bootelf, bootvx
78088733e2cSAndrew Ruder		CONFIG_CMD_ENV_EXISTS	* check existence of env variable
7810c79cda0SMike Frysinger		CONFIG_CMD_EXPORTENV	* export the environment
78203e2ecf6SStephen Warren		CONFIG_CMD_EXT2		* ext2 command support
78303e2ecf6SStephen Warren		CONFIG_CMD_EXT4		* ext4 command support
78416f4d933SStephen Warren		CONFIG_CMD_FS_GENERIC	* filesystem commands (e.g. load, ls)
78516f4d933SStephen Warren					  that work for multiple fs types
78659e890efSChristian Gmeiner		CONFIG_CMD_FS_UUID	* Look up a filesystem UUID
787bdab39d3SMike Frysinger		CONFIG_CMD_SAVEENV	  saveenv
788602ad3b3SJon Loeliger		CONFIG_CMD_FLASH	  flinfo, erase, protect
789602ad3b3SJon Loeliger		CONFIG_CMD_FPGA		  FPGA device initialization support
790a641b979SMike Frysinger		CONFIG_CMD_GO		* the 'go' command (exec code)
791a000b795SKim Phillips		CONFIG_CMD_GREPENV	* search environment
792602ad3b3SJon Loeliger		CONFIG_CMD_I2C		* I2C serial bus support
793602ad3b3SJon Loeliger		CONFIG_CMD_IMI		  iminfo
7948fdf1e0fSVipin Kumar		CONFIG_CMD_IMLS		  List all images found in NOR flash
7954d98b5c8SVincent Stehlé		CONFIG_CMD_IMLS_NAND	* List all images found in NAND flash
7960c79cda0SMike Frysinger		CONFIG_CMD_IMPORTENV	* import an environment
797c167cc02SJoe Hershberger		CONFIG_CMD_INI		* import data from an ini file into the env
798602ad3b3SJon Loeliger		CONFIG_CMD_ITEST	  Integer/string test of 2 values
7994d98b5c8SVincent Stehlé		CONFIG_CMD_LDRINFO	* ldrinfo (display Blackfin loader)
800d22c338eSJoe Hershberger		CONFIG_CMD_LINK_LOCAL	* link-local IP address auto-configuration
801d22c338eSJoe Hershberger					  (169.254.*.*)
802602ad3b3SJon Loeliger		CONFIG_CMD_LOADB	  loadb
803602ad3b3SJon Loeliger		CONFIG_CMD_LOADS	  loads
8044d98b5c8SVincent Stehlé		CONFIG_CMD_MD5SUM	* print md5 message digest
80502c9aa1dSRobin Getz					  (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
80615a33e49SSimon Glass		CONFIG_CMD_MEMINFO	* Display detailed memory information
807602ad3b3SJon Loeliger		CONFIG_CMD_MEMORY	  md, mm, nm, mw, cp, cmp, crc, base,
808a2681707SWolfgang Denk					  loop, loopw
8094d98b5c8SVincent Stehlé		CONFIG_CMD_MEMTEST	* mtest
810602ad3b3SJon Loeliger		CONFIG_CMD_MISC		  Misc functions like sleep etc
811602ad3b3SJon Loeliger		CONFIG_CMD_MMC		* MMC memory mapped support
812602ad3b3SJon Loeliger		CONFIG_CMD_MII		* MII utility commands
813602ad3b3SJon Loeliger		CONFIG_CMD_NET		  bootp, tftpboot, rarpboot
8144d98b5c8SVincent Stehlé		CONFIG_CMD_NFS		  NFS support
815e92739d3SPeter Tyser		CONFIG_CMD_PCA953X	* PCA953x I2C gpio commands
816e92739d3SPeter Tyser		CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
817602ad3b3SJon Loeliger		CONFIG_CMD_PCI		* pciinfo
818602ad3b3SJon Loeliger		CONFIG_CMD_PCMCIA		* PCMCIA support
819602ad3b3SJon Loeliger		CONFIG_CMD_PING		* send ICMP ECHO_REQUEST to network
820602ad3b3SJon Loeliger					  host
821602ad3b3SJon Loeliger		CONFIG_CMD_PORTIO	* Port I/O
822ff048ea9SKenneth Waters		CONFIG_CMD_READ		* Read raw data from partition
823602ad3b3SJon Loeliger		CONFIG_CMD_REGINFO	* Register dump
824602ad3b3SJon Loeliger		CONFIG_CMD_RUN		  run command in env variable
825d304931fSSimon Glass		CONFIG_CMD_SANDBOX	* sb command to access sandbox features
826602ad3b3SJon Loeliger		CONFIG_CMD_SAVES	* save S record dump
827602ad3b3SJon Loeliger		CONFIG_CMD_SDRAM	* print SDRAM configuration information
828602ad3b3SJon Loeliger					  (requires CONFIG_CMD_I2C)
829f61ec45eSEric Nelson		CONFIG_CMD_SF		* Read/write/erase SPI NOR flash
8307d861d95SBob Liu		CONFIG_CMD_SOFTSWITCH	* Soft switch setting command for BF60x
83174de7aefSWolfgang Denk		CONFIG_CMD_SOURCE	  "source" command Support
832602ad3b3SJon Loeliger		CONFIG_CMD_SPI		* SPI serial bus support
8337a83af07SLuca Ceresoli		CONFIG_CMD_TFTPSRV	* TFTP transfer in server mode
8341fb7cd49SSimon Glass		CONFIG_CMD_TFTPPUT	* TFTP put command (upload)
835da83bcd7SJoe Hershberger		CONFIG_CMD_TIME		* run command and report execution time (ARM specific)
836da83bcd7SJoe Hershberger		CONFIG_CMD_TIMER	* access to the system tick timer
837602ad3b3SJon Loeliger		CONFIG_CMD_USB		* USB support
838602ad3b3SJon Loeliger		CONFIG_CMD_CDP		* Cisco Discover Protocol support
839c8339f51SMarek Vasut		CONFIG_CMD_MFSL		* Microblaze FSL support
8404d98b5c8SVincent Stehlé		CONFIG_CMD_XIMG		  Load part of Multi Image
84189c8230dSPrzemyslaw Marczak		CONFIG_CMD_UUID		* Generate random UUID or GUID string
842c609719bSwdenk
843c609719bSwdenk		EXAMPLE: If you want all functions except of network
844c609719bSwdenk		support you can write:
845c609719bSwdenk
846602ad3b3SJon Loeliger		#include "config_cmd_all.h"
847602ad3b3SJon Loeliger		#undef CONFIG_CMD_NET
848c609719bSwdenk
849213bf8c8SGerald Van Baren	Other Commands:
850213bf8c8SGerald Van Baren		fdt (flattened device tree) command: CONFIG_OF_LIBFDT
851c609719bSwdenk
852c609719bSwdenk	Note:	Don't enable the "icache" and "dcache" commands
853602ad3b3SJon Loeliger		(configuration option CONFIG_CMD_CACHE) unless you know
854c609719bSwdenk		what you (and your U-Boot users) are doing. Data
8555b8e76c3SHeiko Schocher		cache cannot be enabled on systems like the
856907208c4SChristophe Leroy		8xx (where accesses to the IMMR region must be
857c609719bSwdenk		uncached), and it cannot be disabled on all other
858c609719bSwdenk		systems where we (mis-) use the data cache to hold an
859c609719bSwdenk		initial stack and some data.
860c609719bSwdenk
861c609719bSwdenk
862c609719bSwdenk		XXX - this list needs to get updated!
863c609719bSwdenk
864302a6487SSimon Glass- Removal of commands
865302a6487SSimon Glass		If no commands are needed to boot, you can disable
866302a6487SSimon Glass		CONFIG_CMDLINE to remove them. In this case, the command line
867302a6487SSimon Glass		will not be available, and when U-Boot wants to execute the
868302a6487SSimon Glass		boot command (on start-up) it will call board_run_command()
869302a6487SSimon Glass		instead. This can reduce image size significantly for very
870302a6487SSimon Glass		simple boot procedures.
871302a6487SSimon Glass
872a5ecbe62SWolfgang Denk- Regular expression support:
873a5ecbe62SWolfgang Denk		CONFIG_REGEX
874a5ecbe62SWolfgang Denk		If this variable is defined, U-Boot is linked against
875a5ecbe62SWolfgang Denk		the SLRE (Super Light Regular Expression) library,
876a5ecbe62SWolfgang Denk		which adds regex support to some commands, as for
877a5ecbe62SWolfgang Denk		example "env grep" and "setexpr".
878a5ecbe62SWolfgang Denk
87945ba8077SSimon Glass- Device tree:
88045ba8077SSimon Glass		CONFIG_OF_CONTROL
88145ba8077SSimon Glass		If this variable is defined, U-Boot will use a device tree
88245ba8077SSimon Glass		to configure its devices, instead of relying on statically
88345ba8077SSimon Glass		compiled #defines in the board file. This option is
88445ba8077SSimon Glass		experimental and only available on a few boards. The device
88545ba8077SSimon Glass		tree is available in the global data as gd->fdt_blob.
88645ba8077SSimon Glass
8872c0f79e4SSimon Glass		U-Boot needs to get its device tree from somewhere. This can
88882f766d1SAlex Deymo		be done using one of the three options below:
889bbb0b128SSimon Glass
890bbb0b128SSimon Glass		CONFIG_OF_EMBED
891bbb0b128SSimon Glass		If this variable is defined, U-Boot will embed a device tree
892bbb0b128SSimon Glass		binary in its image. This device tree file should be in the
893bbb0b128SSimon Glass		board directory and called <soc>-<board>.dts. The binary file
894bbb0b128SSimon Glass		is then picked up in board_init_f() and made available through
895bbb0b128SSimon Glass		the global data structure as gd->blob.
89645ba8077SSimon Glass
8972c0f79e4SSimon Glass		CONFIG_OF_SEPARATE
8982c0f79e4SSimon Glass		If this variable is defined, U-Boot will build a device tree
8992c0f79e4SSimon Glass		binary. It will be called u-boot.dtb. Architecture-specific
9002c0f79e4SSimon Glass		code will locate it at run-time. Generally this works by:
9012c0f79e4SSimon Glass
9022c0f79e4SSimon Glass			cat u-boot.bin u-boot.dtb >image.bin
9032c0f79e4SSimon Glass
9042c0f79e4SSimon Glass		and in fact, U-Boot does this for you, creating a file called
9052c0f79e4SSimon Glass		u-boot-dtb.bin which is useful in the common case. You can
9062c0f79e4SSimon Glass		still use the individual files if you need something more
9072c0f79e4SSimon Glass		exotic.
9082c0f79e4SSimon Glass
90982f766d1SAlex Deymo		CONFIG_OF_BOARD
91082f766d1SAlex Deymo		If this variable is defined, U-Boot will use the device tree
91182f766d1SAlex Deymo		provided by the board at runtime instead of embedding one with
91282f766d1SAlex Deymo		the image. Only boards defining board_fdt_blob_setup() support
91382f766d1SAlex Deymo		this option (see include/fdtdec.h file).
91482f766d1SAlex Deymo
915c609719bSwdenk- Watchdog:
916c609719bSwdenk		CONFIG_WATCHDOG
917c609719bSwdenk		If this variable is defined, it enables watchdog
9186abe6fb6SDetlev Zundel		support for the SoC. There must be support in the SoC
919907208c4SChristophe Leroy		specific code for a watchdog. For the 8xx
920907208c4SChristophe Leroy		CPUs, the SIU Watchdog feature is enabled in the SYPCR
921907208c4SChristophe Leroy		register.  When supported for a specific SoC is
922907208c4SChristophe Leroy		available, then no further board specific code should
923907208c4SChristophe Leroy		be needed to use it.
9246abe6fb6SDetlev Zundel
9256abe6fb6SDetlev Zundel		CONFIG_HW_WATCHDOG
9266abe6fb6SDetlev Zundel		When using a watchdog circuitry external to the used
9276abe6fb6SDetlev Zundel		SoC, then define this variable and provide board
9286abe6fb6SDetlev Zundel		specific code for the "hw_watchdog_reset" function.
929c609719bSwdenk
9307bae0d6fSHeiko Schocher		CONFIG_AT91_HW_WDT_TIMEOUT
9317bae0d6fSHeiko Schocher		specify the timeout in seconds. default 2 seconds.
9327bae0d6fSHeiko Schocher
933c1551ea8Sstroese- U-Boot Version:
934c1551ea8Sstroese		CONFIG_VERSION_VARIABLE
935c1551ea8Sstroese		If this variable is defined, an environment variable
936c1551ea8Sstroese		named "ver" is created by U-Boot showing the U-Boot
937c1551ea8Sstroese		version as printed by the "version" command.
938a1ea8e51SBenoît Thébaudeau		Any change to this variable will be reverted at the
939a1ea8e51SBenoît Thébaudeau		next reset.
940c1551ea8Sstroese
941c609719bSwdenk- Real-Time Clock:
942c609719bSwdenk
943602ad3b3SJon Loeliger		When CONFIG_CMD_DATE is selected, the type of the RTC
944c609719bSwdenk		has to be selected, too. Define exactly one of the
945c609719bSwdenk		following options:
946c609719bSwdenk
947c609719bSwdenk		CONFIG_RTC_PCF8563	- use Philips PCF8563 RTC
9484e8b7544SFabio Estevam		CONFIG_RTC_MC13XXX	- use MC13783 or MC13892 RTC
949c609719bSwdenk		CONFIG_RTC_MC146818	- use MC146818 RTC
9501cb8e980Swdenk		CONFIG_RTC_DS1307	- use Maxim, Inc. DS1307 RTC
951c609719bSwdenk		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC
9527f70e853Swdenk		CONFIG_RTC_DS1338	- use Maxim, Inc. DS1338 RTC
953412921d2SMarkus Niebel		CONFIG_RTC_DS1339	- use Maxim, Inc. DS1339 RTC
9543bac3513Swdenk		CONFIG_RTC_DS164x	- use Dallas DS164x RTC
9559536dfccSTor Krill		CONFIG_RTC_ISL1208	- use Intersil ISL1208 RTC
9564c0d4c3bSwdenk		CONFIG_RTC_MAX6900	- use Maxim, Inc. MAX6900 RTC
9572bd3cab3SChris Packham		CONFIG_RTC_DS1337_NOOSC	- Turn off the OSC output for DS1337
95871d19f30SHeiko Schocher		CONFIG_SYS_RV3029_TCR	- enable trickle charger on
95971d19f30SHeiko Schocher					  RV3029 RTC.
960c609719bSwdenk
961b37c7e5eSwdenk		Note that if the RTC uses I2C, then the I2C interface
962b37c7e5eSwdenk		must also be configured. See I2C Support, below.
963b37c7e5eSwdenk
964e92739d3SPeter Tyser- GPIO Support:
965e92739d3SPeter Tyser		CONFIG_PCA953X		- use NXP's PCA953X series I2C GPIO
966e92739d3SPeter Tyser
9675dec49caSChris Packham		The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
9685dec49caSChris Packham		chip-ngpio pairs that tell the PCA953X driver the number of
9695dec49caSChris Packham		pins supported by a particular chip.
9705dec49caSChris Packham
971e92739d3SPeter Tyser		Note that if the GPIO device uses I2C, then the I2C interface
972e92739d3SPeter Tyser		must also be configured. See I2C Support, below.
973e92739d3SPeter Tyser
974aa53233aSSimon Glass- I/O tracing:
975aa53233aSSimon Glass		When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
976aa53233aSSimon Glass		accesses and can checksum them or write a list of them out
977aa53233aSSimon Glass		to memory. See the 'iotrace' command for details. This is
978aa53233aSSimon Glass		useful for testing device drivers since it can confirm that
979aa53233aSSimon Glass		the driver behaves the same way before and after a code
980aa53233aSSimon Glass		change. Currently this is supported on sandbox and arm. To
981aa53233aSSimon Glass		add support for your architecture, add '#include <iotrace.h>'
982aa53233aSSimon Glass		to the bottom of arch/<arch>/include/asm/io.h and test.
983aa53233aSSimon Glass
984aa53233aSSimon Glass		Example output from the 'iotrace stats' command is below.
985aa53233aSSimon Glass		Note that if the trace buffer is exhausted, the checksum will
986aa53233aSSimon Glass		still continue to operate.
987aa53233aSSimon Glass
988aa53233aSSimon Glass			iotrace is enabled
989aa53233aSSimon Glass			Start:  10000000	(buffer start address)
990aa53233aSSimon Glass			Size:   00010000	(buffer size)
991aa53233aSSimon Glass			Offset: 00000120	(current buffer offset)
992aa53233aSSimon Glass			Output: 10000120	(start + offset)
993aa53233aSSimon Glass			Count:  00000018	(number of trace records)
994aa53233aSSimon Glass			CRC32:  9526fb66	(CRC32 of all trace records)
995aa53233aSSimon Glass
996c609719bSwdenk- Timestamp Support:
997c609719bSwdenk
998c609719bSwdenk		When CONFIG_TIMESTAMP is selected, the timestamp
999c609719bSwdenk		(date and time) of an image is printed by image
1000c609719bSwdenk		commands like bootm or iminfo. This option is
1001602ad3b3SJon Loeliger		automatically enabled when you select CONFIG_CMD_DATE .
1002c609719bSwdenk
1003923c46f9SKarl O. Pinc- Partition Labels (disklabels) Supported:
1004923c46f9SKarl O. Pinc		Zero or more of the following:
1005923c46f9SKarl O. Pinc		CONFIG_MAC_PARTITION   Apple's MacOS partition table.
1006923c46f9SKarl O. Pinc		CONFIG_ISO_PARTITION   ISO partition table, used on CDROM etc.
1007923c46f9SKarl O. Pinc		CONFIG_EFI_PARTITION   GPT partition table, common when EFI is the
1008923c46f9SKarl O. Pinc				       bootloader.  Note 2TB partition limit; see
1009923c46f9SKarl O. Pinc				       disk/part_efi.c
1010923c46f9SKarl O. Pinc		CONFIG_MTD_PARTITIONS  Memory Technology Device partition table.
1011c609719bSwdenk
1012fc843a02SSimon Glass		If IDE or SCSI support is enabled (CONFIG_IDE or
1013c649e3c9SSimon Glass		CONFIG_SCSI) you must configure support for at
1014923c46f9SKarl O. Pinc		least one non-MTD partition type as well.
1015c609719bSwdenk
1016c609719bSwdenk- IDE Reset method:
10174d13cbadSwdenk		CONFIG_IDE_RESET_ROUTINE - this is defined in several
10184d13cbadSwdenk		board configurations files but used nowhere!
1019c609719bSwdenk
10204d13cbadSwdenk		CONFIG_IDE_RESET - is this is defined, IDE Reset will
10214d13cbadSwdenk		be performed by calling the function
10224d13cbadSwdenk			ide_set_reset(int reset)
10234d13cbadSwdenk		which has to be defined in a board specific file
1024c609719bSwdenk
1025c609719bSwdenk- ATAPI Support:
1026c609719bSwdenk		CONFIG_ATAPI
1027c609719bSwdenk
1028c609719bSwdenk		Set this to enable ATAPI support.
1029c609719bSwdenk
1030c40b2956Swdenk- LBA48 Support
1031c40b2956Swdenk		CONFIG_LBA48
1032c40b2956Swdenk
1033c40b2956Swdenk		Set this to enable support for disks larger than 137GB
10344b142febSHeiko Schocher		Also look at CONFIG_SYS_64BIT_LBA.
1035c40b2956Swdenk		Whithout these , LBA48 support uses 32bit variables and will 'only'
1036c40b2956Swdenk		support disks up to 2.1TB.
1037c40b2956Swdenk
10386d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_64BIT_LBA:
1039c40b2956Swdenk			When enabled, makes the IDE subsystem use 64bit sector addresses.
1040c40b2956Swdenk			Default is 32bit.
1041c40b2956Swdenk
1042c609719bSwdenk- SCSI Support:
10436d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
10446d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
10456d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1046c609719bSwdenk		maximum numbers of LUNs, SCSI ID's and target
1047c609719bSwdenk		devices.
1048c609719bSwdenk
1049447c031bSStefan Reinauer		The environment variable 'scsidevs' is set to the number of
1050447c031bSStefan Reinauer		SCSI devices found during the last scan.
1051447c031bSStefan Reinauer
1052c609719bSwdenk- NETWORK Support (PCI):
1053682011ffSwdenk		CONFIG_E1000
1054ce5207e1SKyle Moffett		Support for Intel 8254x/8257x gigabit chips.
1055ce5207e1SKyle Moffett
1056ce5207e1SKyle Moffett		CONFIG_E1000_SPI
1057ce5207e1SKyle Moffett		Utility code for direct access to the SPI bus on Intel 8257x.
1058ce5207e1SKyle Moffett		This does not do anything useful unless you set at least one
1059ce5207e1SKyle Moffett		of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1060ce5207e1SKyle Moffett
1061ce5207e1SKyle Moffett		CONFIG_E1000_SPI_GENERIC
1062ce5207e1SKyle Moffett		Allow generic access to the SPI bus on the Intel 8257x, for
1063ce5207e1SKyle Moffett		example with the "sspi" command.
1064ce5207e1SKyle Moffett
1065ce5207e1SKyle Moffett		CONFIG_CMD_E1000
1066ce5207e1SKyle Moffett		Management command for E1000 devices.  When used on devices
1067ce5207e1SKyle Moffett		with SPI support you can reprogram the EEPROM from U-Boot.
1068682011ffSwdenk
1069c609719bSwdenk		CONFIG_EEPRO100
1070c609719bSwdenk		Support for Intel 82557/82559/82559ER chips.
107111ccc33fSMarcel Ziswiler		Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1072c609719bSwdenk		write routine for first time initialisation.
1073c609719bSwdenk
1074c609719bSwdenk		CONFIG_TULIP
1075c609719bSwdenk		Support for Digital 2114x chips.
1076c609719bSwdenk		Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1077c609719bSwdenk		modem chip initialisation (KS8761/QS6611).
1078c609719bSwdenk
1079c609719bSwdenk		CONFIG_NATSEMI
1080c609719bSwdenk		Support for National dp83815 chips.
1081c609719bSwdenk
1082c609719bSwdenk		CONFIG_NS8382X
1083c609719bSwdenk		Support for National dp8382[01] gigabit chips.
1084c609719bSwdenk
108545219c46Swdenk- NETWORK Support (other):
108645219c46Swdenk
1087c041e9d2SJens Scharsig		CONFIG_DRIVER_AT91EMAC
1088c041e9d2SJens Scharsig		Support for AT91RM9200 EMAC.
1089c041e9d2SJens Scharsig
1090c041e9d2SJens Scharsig			CONFIG_RMII
1091c041e9d2SJens Scharsig			Define this to use reduced MII inteface
1092c041e9d2SJens Scharsig
1093c041e9d2SJens Scharsig			CONFIG_DRIVER_AT91EMAC_QUIET
1094c041e9d2SJens Scharsig			If this defined, the driver is quiet.
1095c041e9d2SJens Scharsig			The driver doen't show link status messages.
1096c041e9d2SJens Scharsig
1097efdd7319SRob Herring		CONFIG_CALXEDA_XGMAC
1098efdd7319SRob Herring		Support for the Calxeda XGMAC device
1099efdd7319SRob Herring
11003bb46d23SAshok		CONFIG_LAN91C96
110145219c46Swdenk		Support for SMSC's LAN91C96 chips.
110245219c46Swdenk
110345219c46Swdenk			CONFIG_LAN91C96_USE_32_BIT
110445219c46Swdenk			Define this to enable 32 bit addressing
110545219c46Swdenk
11063bb46d23SAshok		CONFIG_SMC91111
1107f39748aeSwdenk		Support for SMSC's LAN91C111 chip
1108f39748aeSwdenk
1109f39748aeSwdenk			CONFIG_SMC91111_BASE
1110f39748aeSwdenk			Define this to hold the physical address
1111f39748aeSwdenk			of the device (I/O space)
1112f39748aeSwdenk
1113f39748aeSwdenk			CONFIG_SMC_USE_32_BIT
1114f39748aeSwdenk			Define this if data bus is 32 bits
1115f39748aeSwdenk
1116f39748aeSwdenk			CONFIG_SMC_USE_IOFUNCS
1117f39748aeSwdenk			Define this to use i/o functions instead of macros
1118f39748aeSwdenk			(some hardware wont work with macros)
1119f39748aeSwdenk
1120dc02badaSHeiko Schocher		CONFIG_DRIVER_TI_EMAC
1121dc02badaSHeiko Schocher		Support for davinci emac
1122dc02badaSHeiko Schocher
1123dc02badaSHeiko Schocher			CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1124dc02badaSHeiko Schocher			Define this if you have more then 3 PHYs.
1125dc02badaSHeiko Schocher
1126b3dbf4a5SMacpaul Lin		CONFIG_FTGMAC100
1127b3dbf4a5SMacpaul Lin		Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1128b3dbf4a5SMacpaul Lin
1129b3dbf4a5SMacpaul Lin			CONFIG_FTGMAC100_EGIGA
1130b3dbf4a5SMacpaul Lin			Define this to use GE link update with gigabit PHY.
1131b3dbf4a5SMacpaul Lin			Define this if FTGMAC100 is connected to gigabit PHY.
1132b3dbf4a5SMacpaul Lin			If your system has 10/100 PHY only, it might not occur
1133b3dbf4a5SMacpaul Lin			wrong behavior. Because PHY usually return timeout or
1134b3dbf4a5SMacpaul Lin			useless data when polling gigabit status and gigabit
1135b3dbf4a5SMacpaul Lin			control registers. This behavior won't affect the
1136b3dbf4a5SMacpaul Lin			correctnessof 10/100 link speed update.
1137b3dbf4a5SMacpaul Lin
1138c2fff331SMike Rapoport		CONFIG_SMC911X
1139557b377dSJens Gehrlein		Support for SMSC's LAN911x and LAN921x chips
1140557b377dSJens Gehrlein
1141c2fff331SMike Rapoport			CONFIG_SMC911X_BASE
1142557b377dSJens Gehrlein			Define this to hold the physical address
1143557b377dSJens Gehrlein			of the device (I/O space)
1144557b377dSJens Gehrlein
1145c2fff331SMike Rapoport			CONFIG_SMC911X_32_BIT
1146557b377dSJens Gehrlein			Define this if data bus is 32 bits
1147557b377dSJens Gehrlein
1148c2fff331SMike Rapoport			CONFIG_SMC911X_16_BIT
1149557b377dSJens Gehrlein			Define this if data bus is 16 bits. If your processor
1150557b377dSJens Gehrlein			automatically converts one 32 bit word to two 16 bit
1151c2fff331SMike Rapoport			words you may also try CONFIG_SMC911X_32_BIT.
1152557b377dSJens Gehrlein
11533d0075faSYoshihiro Shimoda		CONFIG_SH_ETHER
11543d0075faSYoshihiro Shimoda		Support for Renesas on-chip Ethernet controller
11553d0075faSYoshihiro Shimoda
11563d0075faSYoshihiro Shimoda			CONFIG_SH_ETHER_USE_PORT
11573d0075faSYoshihiro Shimoda			Define the number of ports to be used
11583d0075faSYoshihiro Shimoda
11593d0075faSYoshihiro Shimoda			CONFIG_SH_ETHER_PHY_ADDR
11603d0075faSYoshihiro Shimoda			Define the ETH PHY's address
11613d0075faSYoshihiro Shimoda
116268260aabSYoshihiro Shimoda			CONFIG_SH_ETHER_CACHE_WRITEBACK
116368260aabSYoshihiro Shimoda			If this option is set, the driver enables cache flush.
116468260aabSYoshihiro Shimoda
1165b2f97cf2SHeiko Schocher- PWM Support:
1166b2f97cf2SHeiko Schocher		CONFIG_PWM_IMX
11675052e819SRobert P. J. Day		Support for PWM module on the imx6.
1168b2f97cf2SHeiko Schocher
11695e124724SVadim Bendebury- TPM Support:
117090899cc0SChe-liang Chiou		CONFIG_TPM
117190899cc0SChe-liang Chiou		Support TPM devices.
117290899cc0SChe-liang Chiou
11730766ad2fSChristophe Ricard		CONFIG_TPM_TIS_INFINEON
11740766ad2fSChristophe Ricard		Support for Infineon i2c bus TPM devices. Only one device
11751b393db5STom Wai-Hong Tam		per system is supported at this time.
11761b393db5STom Wai-Hong Tam
11771b393db5STom Wai-Hong Tam			CONFIG_TPM_TIS_I2C_BURST_LIMITATION
11781b393db5STom Wai-Hong Tam			Define the burst count bytes upper limit
11791b393db5STom Wai-Hong Tam
11803aa74088SChristophe Ricard		CONFIG_TPM_ST33ZP24
11813aa74088SChristophe Ricard		Support for STMicroelectronics TPM devices. Requires DM_TPM support.
11823aa74088SChristophe Ricard
11833aa74088SChristophe Ricard			CONFIG_TPM_ST33ZP24_I2C
11843aa74088SChristophe Ricard			Support for STMicroelectronics ST33ZP24 I2C devices.
11853aa74088SChristophe Ricard			Requires TPM_ST33ZP24 and I2C.
11863aa74088SChristophe Ricard
1187b75fdc11SChristophe Ricard			CONFIG_TPM_ST33ZP24_SPI
1188b75fdc11SChristophe Ricard			Support for STMicroelectronics ST33ZP24 SPI devices.
1189b75fdc11SChristophe Ricard			Requires TPM_ST33ZP24 and SPI.
1190b75fdc11SChristophe Ricard
1191c01939c7SDirk Eibach		CONFIG_TPM_ATMEL_TWI
1192c01939c7SDirk Eibach		Support for Atmel TWI TPM device. Requires I2C support.
1193c01939c7SDirk Eibach
119490899cc0SChe-liang Chiou		CONFIG_TPM_TIS_LPC
11955e124724SVadim Bendebury		Support for generic parallel port TPM devices. Only one device
11965e124724SVadim Bendebury		per system is supported at this time.
11975e124724SVadim Bendebury
11985e124724SVadim Bendebury			CONFIG_TPM_TIS_BASE_ADDRESS
11995e124724SVadim Bendebury			Base address where the generic TPM device is mapped
12005e124724SVadim Bendebury			to. Contemporary x86 systems usually map it at
12015e124724SVadim Bendebury			0xfed40000.
12025e124724SVadim Bendebury
1203be6c1529SReinhard Pfau		CONFIG_CMD_TPM
1204be6c1529SReinhard Pfau		Add tpm monitor functions.
1205be6c1529SReinhard Pfau		Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1206be6c1529SReinhard Pfau		provides monitor access to authorized functions.
1207be6c1529SReinhard Pfau
1208be6c1529SReinhard Pfau		CONFIG_TPM
1209be6c1529SReinhard Pfau		Define this to enable the TPM support library which provides
1210be6c1529SReinhard Pfau		functional interfaces to some TPM commands.
1211be6c1529SReinhard Pfau		Requires support for a TPM device.
1212be6c1529SReinhard Pfau
1213be6c1529SReinhard Pfau		CONFIG_TPM_AUTH_SESSIONS
1214be6c1529SReinhard Pfau		Define this to enable authorized functions in the TPM library.
1215be6c1529SReinhard Pfau		Requires CONFIG_TPM and CONFIG_SHA1.
1216be6c1529SReinhard Pfau
1217c609719bSwdenk- USB Support:
1218c609719bSwdenk		At the moment only the UHCI host controller is
1219064b55cfSHeiko Schocher		supported (PIP405, MIP405); define
1220c609719bSwdenk		CONFIG_USB_UHCI to enable it.
1221c609719bSwdenk		define CONFIG_USB_KEYBOARD to enable the USB Keyboard
122230d56faeSwdenk		and define CONFIG_USB_STORAGE to enable the USB
1223c609719bSwdenk		storage devices.
1224c609719bSwdenk		Note:
1225c609719bSwdenk		Supported are USB Keyboards and USB Floppy drives
1226c609719bSwdenk		(TEAC FD-05PUB).
12274d13cbadSwdenk
12289ab4ce22SSimon Glass		CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
12299ab4ce22SSimon Glass		txfilltuning field in the EHCI controller on reset.
12309ab4ce22SSimon Glass
12316e9e0626SOleksandr Tymoshenko		CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
12326e9e0626SOleksandr Tymoshenko		HW module registers.
12336e9e0626SOleksandr Tymoshenko
123416c8d5e7SWolfgang Denk- USB Device:
123516c8d5e7SWolfgang Denk		Define the below if you wish to use the USB console.
123616c8d5e7SWolfgang Denk		Once firmware is rebuilt from a serial console issue the
123716c8d5e7SWolfgang Denk		command "setenv stdin usbtty; setenv stdout usbtty" and
123811ccc33fSMarcel Ziswiler		attach your USB cable. The Unix command "dmesg" should print
123916c8d5e7SWolfgang Denk		it has found a new device. The environment variable usbtty
124016c8d5e7SWolfgang Denk		can be set to gserial or cdc_acm to enable your device to
124116c8d5e7SWolfgang Denk		appear to a USB host as a Linux gserial device or a
124216c8d5e7SWolfgang Denk		Common Device Class Abstract Control Model serial device.
124316c8d5e7SWolfgang Denk		If you select usbtty = gserial you should be able to enumerate
124416c8d5e7SWolfgang Denk		a Linux host by
124516c8d5e7SWolfgang Denk		# modprobe usbserial vendor=0xVendorID product=0xProductID
124616c8d5e7SWolfgang Denk		else if using cdc_acm, simply setting the environment
124716c8d5e7SWolfgang Denk		variable usbtty to be cdc_acm should suffice. The following
124816c8d5e7SWolfgang Denk		might be defined in YourBoardName.h
124916c8d5e7SWolfgang Denk
125016c8d5e7SWolfgang Denk			CONFIG_USB_DEVICE
125116c8d5e7SWolfgang Denk			Define this to build a UDC device
125216c8d5e7SWolfgang Denk
125316c8d5e7SWolfgang Denk			CONFIG_USB_TTY
125416c8d5e7SWolfgang Denk			Define this to have a tty type of device available to
125516c8d5e7SWolfgang Denk			talk to the UDC device
125616c8d5e7SWolfgang Denk
1257f9da0f89SVipin KUMAR			CONFIG_USBD_HS
1258f9da0f89SVipin KUMAR			Define this to enable the high speed support for usb
1259f9da0f89SVipin KUMAR			device and usbtty. If this feature is enabled, a routine
1260f9da0f89SVipin KUMAR			int is_usbd_high_speed(void)
1261f9da0f89SVipin KUMAR			also needs to be defined by the driver to dynamically poll
1262f9da0f89SVipin KUMAR			whether the enumeration has succeded at high speed or full
1263f9da0f89SVipin KUMAR			speed.
1264f9da0f89SVipin KUMAR
12656d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_CONSOLE_IS_IN_ENV
126616c8d5e7SWolfgang Denk			Define this if you want stdin, stdout &/or stderr to
126716c8d5e7SWolfgang Denk			be set to usbtty.
126816c8d5e7SWolfgang Denk
126916c8d5e7SWolfgang Denk		If you have a USB-IF assigned VendorID then you may wish to
127016c8d5e7SWolfgang Denk		define your own vendor specific values either in BoardName.h
127116c8d5e7SWolfgang Denk		or directly in usbd_vendor_info.h. If you don't define
127216c8d5e7SWolfgang Denk		CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
127316c8d5e7SWolfgang Denk		CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
127416c8d5e7SWolfgang Denk		should pretend to be a Linux device to it's target host.
127516c8d5e7SWolfgang Denk
127616c8d5e7SWolfgang Denk			CONFIG_USBD_MANUFACTURER
127716c8d5e7SWolfgang Denk			Define this string as the name of your company for
127816c8d5e7SWolfgang Denk			- CONFIG_USBD_MANUFACTURER "my company"
127916c8d5e7SWolfgang Denk
128016c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCT_NAME
128116c8d5e7SWolfgang Denk			Define this string as the name of your product
128216c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCT_NAME "acme usb device"
128316c8d5e7SWolfgang Denk
128416c8d5e7SWolfgang Denk			CONFIG_USBD_VENDORID
128516c8d5e7SWolfgang Denk			Define this as your assigned Vendor ID from the USB
128616c8d5e7SWolfgang Denk			Implementors Forum. This *must* be a genuine Vendor ID
128716c8d5e7SWolfgang Denk			to avoid polluting the USB namespace.
128816c8d5e7SWolfgang Denk			- CONFIG_USBD_VENDORID 0xFFFF
128916c8d5e7SWolfgang Denk
129016c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCTID
129116c8d5e7SWolfgang Denk			Define this as the unique Product ID
129216c8d5e7SWolfgang Denk			for your device
129316c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCTID 0xFFFF
1294c609719bSwdenk
1295d70a560fSIgor Grinberg- ULPI Layer Support:
1296d70a560fSIgor Grinberg		The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1297d70a560fSIgor Grinberg		the generic ULPI layer. The generic layer accesses the ULPI PHY
1298d70a560fSIgor Grinberg		via the platform viewport, so you need both the genric layer and
1299d70a560fSIgor Grinberg		the viewport enabled. Currently only Chipidea/ARC based
1300d70a560fSIgor Grinberg		viewport is supported.
1301d70a560fSIgor Grinberg		To enable the ULPI layer support, define CONFIG_USB_ULPI and
1302d70a560fSIgor Grinberg		CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
13036d365ea0SLucas Stach		If your ULPI phy needs a different reference clock than the
13046d365ea0SLucas Stach		standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
13056d365ea0SLucas Stach		the appropriate value in Hz.
1306c609719bSwdenk
1307c609719bSwdenk- MMC Support:
1308c609719bSwdenk		The MMC controller on the Intel PXA is supported. To
1309c609719bSwdenk		enable this define CONFIG_MMC. The MMC can be
1310c609719bSwdenk		accessed from the boot prompt by mapping the device
1311c609719bSwdenk		to physical memory similar to flash. Command line is
1312602ad3b3SJon Loeliger		enabled with CONFIG_CMD_MMC. The MMC driver also works with
1313602ad3b3SJon Loeliger		the FAT fs. This is enabled with CONFIG_CMD_FAT.
1314c609719bSwdenk
1315afb35666SYoshihiro Shimoda		CONFIG_SH_MMCIF
1316afb35666SYoshihiro Shimoda		Support for Renesas on-chip MMCIF controller
1317afb35666SYoshihiro Shimoda
1318afb35666SYoshihiro Shimoda			CONFIG_SH_MMCIF_ADDR
1319afb35666SYoshihiro Shimoda			Define the base address of MMCIF registers
1320afb35666SYoshihiro Shimoda
1321afb35666SYoshihiro Shimoda			CONFIG_SH_MMCIF_CLK
1322afb35666SYoshihiro Shimoda			Define the clock frequency for MMCIF
1323afb35666SYoshihiro Shimoda
13241fd93c6eSPierre Aubert		CONFIG_SUPPORT_EMMC_BOOT
13251fd93c6eSPierre Aubert		Enable some additional features of the eMMC boot partitions.
13261fd93c6eSPierre Aubert
13271fd93c6eSPierre Aubert		CONFIG_SUPPORT_EMMC_RPMB
13281fd93c6eSPierre Aubert		Enable the commands for reading, writing and programming the
13291fd93c6eSPierre Aubert		key for the Replay Protection Memory Block partition in eMMC.
13301fd93c6eSPierre Aubert
1331b3ba6e94STom Rini- USB Device Firmware Update (DFU) class support:
133201acd6abSPaul Kocialkowski		CONFIG_USB_FUNCTION_DFU
1333b3ba6e94STom Rini		This enables the USB portion of the DFU USB class
1334b3ba6e94STom Rini
1335b3ba6e94STom Rini		CONFIG_CMD_DFU
1336b3ba6e94STom Rini		This enables the command "dfu" which is used to have
1337b3ba6e94STom Rini		U-Boot create a DFU class device via USB.  This command
1338b3ba6e94STom Rini		requires that the "dfu_alt_info" environment variable be
1339b3ba6e94STom Rini		set and define the alt settings to expose to the host.
1340b3ba6e94STom Rini
1341b3ba6e94STom Rini		CONFIG_DFU_MMC
1342b3ba6e94STom Rini		This enables support for exposing (e)MMC devices via DFU.
1343b3ba6e94STom Rini
1344c6631764SPantelis Antoniou		CONFIG_DFU_NAND
1345c6631764SPantelis Antoniou		This enables support for exposing NAND devices via DFU.
1346c6631764SPantelis Antoniou
1347a9479f04SAfzal Mohammed		CONFIG_DFU_RAM
1348a9479f04SAfzal Mohammed		This enables support for exposing RAM via DFU.
1349a9479f04SAfzal Mohammed		Note: DFU spec refer to non-volatile memory usage, but
1350a9479f04SAfzal Mohammed		allow usages beyond the scope of spec - here RAM usage,
1351a9479f04SAfzal Mohammed		one that would help mostly the developer.
1352a9479f04SAfzal Mohammed
1353e7e75c70SHeiko Schocher		CONFIG_SYS_DFU_DATA_BUF_SIZE
1354e7e75c70SHeiko Schocher		Dfu transfer uses a buffer before writing data to the
1355e7e75c70SHeiko Schocher		raw storage device. Make the size (in bytes) of this buffer
1356e7e75c70SHeiko Schocher		configurable. The size of this buffer is also configurable
1357e7e75c70SHeiko Schocher		through the "dfu_bufsiz" environment variable.
1358e7e75c70SHeiko Schocher
1359ea2453d5SPantelis Antoniou		CONFIG_SYS_DFU_MAX_FILE_SIZE
1360ea2453d5SPantelis Antoniou		When updating files rather than the raw storage device,
1361ea2453d5SPantelis Antoniou		we use a static buffer to copy the file into and then write
1362ea2453d5SPantelis Antoniou		the buffer once we've been given the whole file.  Define
1363ea2453d5SPantelis Antoniou		this to the maximum filesize (in bytes) for the buffer.
1364ea2453d5SPantelis Antoniou		Default is 4 MiB if undefined.
1365ea2453d5SPantelis Antoniou
1366001a8319SHeiko Schocher		DFU_DEFAULT_POLL_TIMEOUT
1367001a8319SHeiko Schocher		Poll timeout [ms], is the timeout a device can send to the
1368001a8319SHeiko Schocher		host. The host must wait for this timeout before sending
1369001a8319SHeiko Schocher		a subsequent DFU_GET_STATUS request to the device.
1370001a8319SHeiko Schocher
1371001a8319SHeiko Schocher		DFU_MANIFEST_POLL_TIMEOUT
1372001a8319SHeiko Schocher		Poll timeout [ms], which the device sends to the host when
1373001a8319SHeiko Schocher		entering dfuMANIFEST state. Host waits this timeout, before
1374001a8319SHeiko Schocher		sending again an USB request to the device.
1375001a8319SHeiko Schocher
13763aab70afSSebastian Siewior- USB Device Android Fastboot support:
137717da3c0cSPaul Kocialkowski		CONFIG_USB_FUNCTION_FASTBOOT
137817da3c0cSPaul Kocialkowski		This enables the USB part of the fastboot gadget
137917da3c0cSPaul Kocialkowski
13803aab70afSSebastian Siewior		CONFIG_CMD_FASTBOOT
13813aab70afSSebastian Siewior		This enables the command "fastboot" which enables the Android
13823aab70afSSebastian Siewior		fastboot mode for the platform's USB device. Fastboot is a USB
13833aab70afSSebastian Siewior		protocol for downloading images, flashing and device control
13843aab70afSSebastian Siewior		used on Android devices.
13853aab70afSSebastian Siewior		See doc/README.android-fastboot for more information.
13863aab70afSSebastian Siewior
13873aab70afSSebastian Siewior		CONFIG_ANDROID_BOOT_IMAGE
13883aab70afSSebastian Siewior		This enables support for booting images which use the Android
13893aab70afSSebastian Siewior		image format header.
13903aab70afSSebastian Siewior
1391a588d99aSPaul Kocialkowski		CONFIG_FASTBOOT_BUF_ADDR
13923aab70afSSebastian Siewior		The fastboot protocol requires a large memory buffer for
13933aab70afSSebastian Siewior		downloads. Define this to the starting RAM address to use for
13943aab70afSSebastian Siewior		downloaded images.
13953aab70afSSebastian Siewior
1396a588d99aSPaul Kocialkowski		CONFIG_FASTBOOT_BUF_SIZE
13973aab70afSSebastian Siewior		The fastboot protocol requires a large memory buffer for
13983aab70afSSebastian Siewior		downloads. This buffer should be as large as possible for a
13993aab70afSSebastian Siewior		platform. Define this to the size available RAM for fastboot.
14003aab70afSSebastian Siewior
1401d1b5ed07SSteve Rae		CONFIG_FASTBOOT_FLASH
1402d1b5ed07SSteve Rae		The fastboot protocol includes a "flash" command for writing
1403d1b5ed07SSteve Rae		the downloaded image to a non-volatile storage device. Define
1404d1b5ed07SSteve Rae		this to enable the "fastboot flash" command.
1405d1b5ed07SSteve Rae
1406d1b5ed07SSteve Rae		CONFIG_FASTBOOT_FLASH_MMC_DEV
1407d1b5ed07SSteve Rae		The fastboot "flash" command requires additional information
1408d1b5ed07SSteve Rae		regarding the non-volatile storage device. Define this to
1409d1b5ed07SSteve Rae		the eMMC device that fastboot should use to store the image.
1410d1b5ed07SSteve Rae
14110ff7e585SSteve Rae		CONFIG_FASTBOOT_GPT_NAME
14120ff7e585SSteve Rae		The fastboot "flash" command supports writing the downloaded
14130ff7e585SSteve Rae		image to the Protective MBR and the Primary GUID Partition
14140ff7e585SSteve Rae		Table. (Additionally, this downloaded image is post-processed
14150ff7e585SSteve Rae		to generate and write the Backup GUID Partition Table.)
14160ff7e585SSteve Rae		This occurs when the specified "partition name" on the
14170ff7e585SSteve Rae		"fastboot flash" command line matches this value.
14186f6c8630SPetr Kulhavy		The default is "gpt" if undefined.
14190ff7e585SSteve Rae
1420b6dd69a4SPetr Kulhavy		CONFIG_FASTBOOT_MBR_NAME
1421b6dd69a4SPetr Kulhavy		The fastboot "flash" command supports writing the downloaded
1422b6dd69a4SPetr Kulhavy		image to DOS MBR.
1423b6dd69a4SPetr Kulhavy		This occurs when the "partition name" specified on the
1424b6dd69a4SPetr Kulhavy		"fastboot flash" command line matches this value.
1425b6dd69a4SPetr Kulhavy		If not defined the default value "mbr" is used.
1426b6dd69a4SPetr Kulhavy
14276705d81eSwdenk- Journaling Flash filesystem support:
1428b2482dffSSimon Glass		CONFIG_JFFS2_NAND
14296705d81eSwdenk		Define these for a default partition on a NAND device
14306705d81eSwdenk
14316d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_JFFS2_FIRST_SECTOR,
14326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
14336705d81eSwdenk		Define these for a default partition on a NOR device
14346705d81eSwdenk
1435c609719bSwdenk- Keyboard Support:
143639f615edSSimon Glass		See Kconfig help for available keyboard drivers.
143739f615edSSimon Glass
143839f615edSSimon Glass		CONFIG_KEYBOARD
143939f615edSSimon Glass
144039f615edSSimon Glass		Define this to enable a custom keyboard support.
144139f615edSSimon Glass		This simply calls drv_keyboard_init() which must be
144239f615edSSimon Glass		defined in your board-specific files. This option is deprecated
144339f615edSSimon Glass		and is only used by novena. For new boards, use driver model
144439f615edSSimon Glass		instead.
1445c609719bSwdenk
1446c609719bSwdenk- Video support:
14477d3053fbSTimur Tabi		CONFIG_FSL_DIU_FB
14487d3053fbSTimur Tabi		Enable the Freescale DIU video driver.	Reference boards for
14497d3053fbSTimur Tabi		SOCs that have a DIU should define this macro to enable DIU
14507d3053fbSTimur Tabi		support, and should also define these other macros:
14517d3053fbSTimur Tabi
14527d3053fbSTimur Tabi			CONFIG_SYS_DIU_ADDR
14537d3053fbSTimur Tabi			CONFIG_VIDEO
14547d3053fbSTimur Tabi			CONFIG_CFB_CONSOLE
14557d3053fbSTimur Tabi			CONFIG_VIDEO_SW_CURSOR
14567d3053fbSTimur Tabi			CONFIG_VGA_AS_SINGLE_DEVICE
14577d3053fbSTimur Tabi			CONFIG_VIDEO_LOGO
14587d3053fbSTimur Tabi			CONFIG_VIDEO_BMP_LOGO
14597d3053fbSTimur Tabi
1460ba8e76bdSTimur Tabi		The DIU driver will look for the 'video-mode' environment
1461ba8e76bdSTimur Tabi		variable, and if defined, enable the DIU as a console during
14628eca9439SFabio Estevam		boot.  See the documentation file doc/README.video for a
1463ba8e76bdSTimur Tabi		description of this variable.
14647d3053fbSTimur Tabi
1465c609719bSwdenk- LCD Support:	CONFIG_LCD
1466c609719bSwdenk
1467c609719bSwdenk		Define this to enable LCD support (for output to LCD
1468c609719bSwdenk		display); also select one of the supported displays
1469c609719bSwdenk		by defining one of these:
1470c609719bSwdenk
147139cf4804SStelian Pop		CONFIG_ATMEL_LCD:
147239cf4804SStelian Pop
147339cf4804SStelian Pop			HITACHI TX09D70VM1CCA, 3.5", 240x320.
147439cf4804SStelian Pop
1475fd3103bbSwdenk		CONFIG_NEC_NL6448AC33:
1476c609719bSwdenk
1477fd3103bbSwdenk			NEC NL6448AC33-18. Active, color, single scan.
1478c609719bSwdenk
1479fd3103bbSwdenk		CONFIG_NEC_NL6448BC20
1480c609719bSwdenk
1481fd3103bbSwdenk			NEC NL6448BC20-08. 6.5", 640x480.
1482fd3103bbSwdenk			Active, color, single scan.
1483fd3103bbSwdenk
1484fd3103bbSwdenk		CONFIG_NEC_NL6448BC33_54
1485fd3103bbSwdenk
1486fd3103bbSwdenk			NEC NL6448BC33-54. 10.4", 640x480.
1487c609719bSwdenk			Active, color, single scan.
1488c609719bSwdenk
1489c609719bSwdenk		CONFIG_SHARP_16x9
1490c609719bSwdenk
1491c609719bSwdenk			Sharp 320x240. Active, color, single scan.
1492c609719bSwdenk			It isn't 16x9, and I am not sure what it is.
1493c609719bSwdenk
1494c609719bSwdenk		CONFIG_SHARP_LQ64D341
1495c609719bSwdenk
1496c609719bSwdenk			Sharp LQ64D341 display, 640x480.
1497c609719bSwdenk			Active, color, single scan.
1498c609719bSwdenk
1499c609719bSwdenk		CONFIG_HLD1045
1500c609719bSwdenk
1501c609719bSwdenk			HLD1045 display, 640x480.
1502c609719bSwdenk			Active, color, single scan.
1503c609719bSwdenk
1504c609719bSwdenk		CONFIG_OPTREX_BW
1505c609719bSwdenk
1506c609719bSwdenk			Optrex	 CBL50840-2 NF-FW 99 22 M5
1507c609719bSwdenk			or
1508c609719bSwdenk			Hitachi	 LMG6912RPFC-00T
1509c609719bSwdenk			or
1510c609719bSwdenk			Hitachi	 SP14Q002
1511c609719bSwdenk
1512c609719bSwdenk			320x240. Black & white.
1513c609719bSwdenk
1514676d319eSSimon Glass		CONFIG_LCD_ALIGNMENT
1515676d319eSSimon Glass
1516b445bbb4SJeremiah Mahler		Normally the LCD is page-aligned (typically 4KB). If this is
1517676d319eSSimon Glass		defined then the LCD will be aligned to this value instead.
1518676d319eSSimon Glass		For ARM it is sometimes useful to use MMU_SECTION_SIZE
1519676d319eSSimon Glass		here, since it is cheaper to change data cache settings on
1520676d319eSSimon Glass		a per-section basis.
1521676d319eSSimon Glass
1522676d319eSSimon Glass
1523604c7d4aSHannes Petermaier		CONFIG_LCD_ROTATION
1524604c7d4aSHannes Petermaier
1525604c7d4aSHannes Petermaier		Sometimes, for example if the display is mounted in portrait
1526604c7d4aSHannes Petermaier		mode or even if it's mounted landscape but rotated by 180degree,
1527604c7d4aSHannes Petermaier		we need to rotate our content of the display relative to the
1528604c7d4aSHannes Petermaier		framebuffer, so that user can read the messages which are
1529604c7d4aSHannes Petermaier		printed out.
1530604c7d4aSHannes Petermaier		Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1531604c7d4aSHannes Petermaier		initialized with a given rotation from "vl_rot" out of
1532604c7d4aSHannes Petermaier		"vidinfo_t" which is provided by the board specific code.
1533604c7d4aSHannes Petermaier		The value for vl_rot is coded as following (matching to
1534604c7d4aSHannes Petermaier		fbcon=rotate:<n> linux-kernel commandline):
1535604c7d4aSHannes Petermaier		0 = no rotation respectively 0 degree
1536604c7d4aSHannes Petermaier		1 = 90 degree rotation
1537604c7d4aSHannes Petermaier		2 = 180 degree rotation
1538604c7d4aSHannes Petermaier		3 = 270 degree rotation
1539604c7d4aSHannes Petermaier
1540604c7d4aSHannes Petermaier		If CONFIG_LCD_ROTATION is not defined, the console will be
1541604c7d4aSHannes Petermaier		initialized with 0degree rotation.
1542604c7d4aSHannes Petermaier
154345d7f525STom Wai-Hong Tam		CONFIG_LCD_BMP_RLE8
154445d7f525STom Wai-Hong Tam
154545d7f525STom Wai-Hong Tam		Support drawing of RLE8-compressed bitmaps on the LCD.
154645d7f525STom Wai-Hong Tam
1547735987c5STom Wai-Hong Tam		CONFIG_I2C_EDID
1548735987c5STom Wai-Hong Tam
1549735987c5STom Wai-Hong Tam		Enables an 'i2c edid' command which can read EDID
1550735987c5STom Wai-Hong Tam		information over I2C from an attached LCD display.
1551735987c5STom Wai-Hong Tam
15527152b1d0Swdenk- Splash Screen Support: CONFIG_SPLASH_SCREEN
1553d791b1dcSwdenk
1554d791b1dcSwdenk		If this option is set, the environment is checked for
1555d791b1dcSwdenk		a variable "splashimage". If found, the usual display
1556d791b1dcSwdenk		of logo, copyright and system information on the LCD
1557e94d2cd9Swdenk		is suppressed and the BMP image at the address
1558d791b1dcSwdenk		specified in "splashimage" is loaded instead. The
1559d791b1dcSwdenk		console is redirected to the "nulldev", too. This
1560d791b1dcSwdenk		allows for a "silent" boot where a splash screen is
1561d791b1dcSwdenk		loaded very quickly after power-on.
1562d791b1dcSwdenk
1563c0880485SNikita Kiryanov		CONFIG_SPLASHIMAGE_GUARD
1564c0880485SNikita Kiryanov
1565c0880485SNikita Kiryanov		If this option is set, then U-Boot will prevent the environment
1566c0880485SNikita Kiryanov		variable "splashimage" from being set to a problematic address
1567ab5645f1SFabio Estevam		(see doc/README.displaying-bmps).
1568c0880485SNikita Kiryanov		This option is useful for targets where, due to alignment
1569c0880485SNikita Kiryanov		restrictions, an improperly aligned BMP image will cause a data
1570c0880485SNikita Kiryanov		abort. If you think you will not have problems with unaligned
1571c0880485SNikita Kiryanov		accesses (for example because your toolchain prevents them)
1572c0880485SNikita Kiryanov		there is no need to set this option.
1573c0880485SNikita Kiryanov
15741ca298ceSMatthias Weisser		CONFIG_SPLASH_SCREEN_ALIGN
15751ca298ceSMatthias Weisser
15761ca298ceSMatthias Weisser		If this option is set the splash image can be freely positioned
15771ca298ceSMatthias Weisser		on the screen. Environment variable "splashpos" specifies the
15781ca298ceSMatthias Weisser		position as "x,y". If a positive number is given it is used as
15791ca298ceSMatthias Weisser		number of pixel from left/top. If a negative number is given it
15801ca298ceSMatthias Weisser		is used as number of pixel from right/bottom. You can also
15811ca298ceSMatthias Weisser		specify 'm' for centering the image.
15821ca298ceSMatthias Weisser
15831ca298ceSMatthias Weisser		Example:
15841ca298ceSMatthias Weisser		setenv splashpos m,m
15851ca298ceSMatthias Weisser			=> image at center of screen
15861ca298ceSMatthias Weisser
15871ca298ceSMatthias Weisser		setenv splashpos 30,20
15881ca298ceSMatthias Weisser			=> image at x = 30 and y = 20
15891ca298ceSMatthias Weisser
15901ca298ceSMatthias Weisser		setenv splashpos -10,m
15911ca298ceSMatthias Weisser			=> vertically centered image
15921ca298ceSMatthias Weisser			   at x = dspWidth - bmpWidth - 9
15931ca298ceSMatthias Weisser
159498f4a3dfSStefan Roese- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
159598f4a3dfSStefan Roese
159698f4a3dfSStefan Roese		If this option is set, additionally to standard BMP
159798f4a3dfSStefan Roese		images, gzipped BMP images can be displayed via the
159898f4a3dfSStefan Roese		splashscreen support or the bmp command.
159998f4a3dfSStefan Roese
1600d5011762SAnatolij Gustschin- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1601d5011762SAnatolij Gustschin
1602d5011762SAnatolij Gustschin		If this option is set, 8-bit RLE compressed BMP images
1603d5011762SAnatolij Gustschin		can be displayed via the splashscreen support or the
1604d5011762SAnatolij Gustschin		bmp command.
1605d5011762SAnatolij Gustschin
1606c29fdfc1Swdenk- Compression support:
16078ef70478SKees Cook		CONFIG_GZIP
16088ef70478SKees Cook
16098ef70478SKees Cook		Enabled by default to support gzip compressed images.
16108ef70478SKees Cook
1611c29fdfc1Swdenk		CONFIG_BZIP2
1612c29fdfc1Swdenk
1613c29fdfc1Swdenk		If this option is set, support for bzip2 compressed
1614c29fdfc1Swdenk		images is included. If not, only uncompressed and gzip
1615c29fdfc1Swdenk		compressed images are supported.
1616c29fdfc1Swdenk
1617c29fdfc1Swdenk		NOTE: the bzip2 algorithm requires a lot of RAM, so
16186d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1619c29fdfc1Swdenk		be at least 4MB.
1620d791b1dcSwdenk
162117ea1177Swdenk- MII/PHY support:
162217ea1177Swdenk		CONFIG_PHY_ADDR
162317ea1177Swdenk
162417ea1177Swdenk		The address of PHY on MII bus.
162517ea1177Swdenk
162617ea1177Swdenk		CONFIG_PHY_CLOCK_FREQ (ppc4xx)
162717ea1177Swdenk
162817ea1177Swdenk		The clock frequency of the MII bus
162917ea1177Swdenk
163017ea1177Swdenk		CONFIG_PHY_RESET_DELAY
163117ea1177Swdenk
163217ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
163317ea1177Swdenk		reset before any MII register access is possible.
163417ea1177Swdenk		For such PHY, set this option to the usec delay
163517ea1177Swdenk		required. (minimum 300usec for LXT971A)
163617ea1177Swdenk
163717ea1177Swdenk		CONFIG_PHY_CMD_DELAY (ppc4xx)
163817ea1177Swdenk
163917ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
164017ea1177Swdenk		command issued before MII status register can be read
164117ea1177Swdenk
1642c609719bSwdenk- IP address:
1643c609719bSwdenk		CONFIG_IPADDR
1644c609719bSwdenk
1645c609719bSwdenk		Define a default value for the IP address to use for
164611ccc33fSMarcel Ziswiler		the default Ethernet interface, in case this is not
1647c609719bSwdenk		determined through e.g. bootp.
16481ebcd654SWolfgang Denk		(Environment variable "ipaddr")
1649c609719bSwdenk
1650c609719bSwdenk- Server IP address:
1651c609719bSwdenk		CONFIG_SERVERIP
1652c609719bSwdenk
1653c609719bSwdenk		Defines a default value for the IP address of a TFTP
1654c609719bSwdenk		server to contact when using the "tftboot" command.
16551ebcd654SWolfgang Denk		(Environment variable "serverip")
1656c609719bSwdenk
165797cfe861SRobin Getz		CONFIG_KEEP_SERVERADDR
165897cfe861SRobin Getz
165997cfe861SRobin Getz		Keeps the server's MAC address, in the env 'serveraddr'
166097cfe861SRobin Getz		for passing to bootargs (like Linux's netconsole option)
166197cfe861SRobin Getz
16621ebcd654SWolfgang Denk- Gateway IP address:
16631ebcd654SWolfgang Denk		CONFIG_GATEWAYIP
16641ebcd654SWolfgang Denk
16651ebcd654SWolfgang Denk		Defines a default value for the IP address of the
16661ebcd654SWolfgang Denk		default router where packets to other networks are
16671ebcd654SWolfgang Denk		sent to.
16681ebcd654SWolfgang Denk		(Environment variable "gatewayip")
16691ebcd654SWolfgang Denk
16701ebcd654SWolfgang Denk- Subnet mask:
16711ebcd654SWolfgang Denk		CONFIG_NETMASK
16721ebcd654SWolfgang Denk
16731ebcd654SWolfgang Denk		Defines a default value for the subnet mask (or
16741ebcd654SWolfgang Denk		routing prefix) which is used to determine if an IP
16751ebcd654SWolfgang Denk		address belongs to the local subnet or needs to be
16761ebcd654SWolfgang Denk		forwarded through a router.
16771ebcd654SWolfgang Denk		(Environment variable "netmask")
16781ebcd654SWolfgang Denk
167953a5c424SDavid Updegraff- Multicast TFTP Mode:
168053a5c424SDavid Updegraff		CONFIG_MCAST_TFTP
168153a5c424SDavid Updegraff
168253a5c424SDavid Updegraff		Defines whether you want to support multicast TFTP as per
168353a5c424SDavid Updegraff		rfc-2090; for example to work with atftp.  Lets lots of targets
168411ccc33fSMarcel Ziswiler		tftp down the same boot image concurrently.  Note: the Ethernet
168553a5c424SDavid Updegraff		driver in use must provide a function: mcast() to join/leave a
168653a5c424SDavid Updegraff		multicast group.
168753a5c424SDavid Updegraff
1688c609719bSwdenk- BOOTP Recovery Mode:
1689c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY
1690c609719bSwdenk
1691c609719bSwdenk		If you have many targets in a network that try to
1692c609719bSwdenk		boot using BOOTP, you may want to avoid that all
1693c609719bSwdenk		systems send out BOOTP requests at precisely the same
1694c609719bSwdenk		moment (which would happen for instance at recovery
1695c609719bSwdenk		from a power failure, when all systems will try to
1696c609719bSwdenk		boot, thus flooding the BOOTP server. Defining
1697c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1698c609719bSwdenk		inserted before sending out BOOTP requests. The
16996c33c785SWolfgang Denk		following delays are inserted then:
1700c609719bSwdenk
1701c609719bSwdenk		1st BOOTP request:	delay 0 ... 1 sec
1702c609719bSwdenk		2nd BOOTP request:	delay 0 ... 2 sec
1703c609719bSwdenk		3rd BOOTP request:	delay 0 ... 4 sec
1704c609719bSwdenk		4th and following
1705c609719bSwdenk		BOOTP requests:		delay 0 ... 8 sec
1706c609719bSwdenk
170792ac8accSThierry Reding		CONFIG_BOOTP_ID_CACHE_SIZE
170892ac8accSThierry Reding
170992ac8accSThierry Reding		BOOTP packets are uniquely identified using a 32-bit ID. The
171092ac8accSThierry Reding		server will copy the ID from client requests to responses and
171192ac8accSThierry Reding		U-Boot will use this to determine if it is the destination of
171292ac8accSThierry Reding		an incoming response. Some servers will check that addresses
171392ac8accSThierry Reding		aren't in use before handing them out (usually using an ARP
171492ac8accSThierry Reding		ping) and therefore take up to a few hundred milliseconds to
171592ac8accSThierry Reding		respond. Network congestion may also influence the time it
171692ac8accSThierry Reding		takes for a response to make it back to the client. If that
171792ac8accSThierry Reding		time is too long, U-Boot will retransmit requests. In order
171892ac8accSThierry Reding		to allow earlier responses to still be accepted after these
171992ac8accSThierry Reding		retransmissions, U-Boot's BOOTP client keeps a small cache of
172092ac8accSThierry Reding		IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
172192ac8accSThierry Reding		cache. The default is to keep IDs for up to four outstanding
172292ac8accSThierry Reding		requests. Increasing this will allow U-Boot to accept offers
172392ac8accSThierry Reding		from a BOOTP client in networks with unusually high latency.
172492ac8accSThierry Reding
1725fe389a82Sstroese- DHCP Advanced Options:
17261fe80d79SJon Loeliger		You can fine tune the DHCP functionality by defining
17271fe80d79SJon Loeliger		CONFIG_BOOTP_* symbols:
1728fe389a82Sstroese
17291fe80d79SJon Loeliger		CONFIG_BOOTP_SUBNETMASK
17301fe80d79SJon Loeliger		CONFIG_BOOTP_GATEWAY
17311fe80d79SJon Loeliger		CONFIG_BOOTP_HOSTNAME
17321fe80d79SJon Loeliger		CONFIG_BOOTP_NISDOMAIN
17331fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTPATH
17341fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTFILESIZE
17351fe80d79SJon Loeliger		CONFIG_BOOTP_DNS
17361fe80d79SJon Loeliger		CONFIG_BOOTP_DNS2
17371fe80d79SJon Loeliger		CONFIG_BOOTP_SEND_HOSTNAME
17381fe80d79SJon Loeliger		CONFIG_BOOTP_NTPSERVER
17391fe80d79SJon Loeliger		CONFIG_BOOTP_TIMEOFFSET
17401fe80d79SJon Loeliger		CONFIG_BOOTP_VENDOREX
17412c00e099SJoe Hershberger		CONFIG_BOOTP_MAY_FAIL
1742fe389a82Sstroese
17435d110f0aSWilson Callan		CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
17445d110f0aSWilson Callan		environment variable, not the BOOTP server.
1745fe389a82Sstroese
17462c00e099SJoe Hershberger		CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
17472c00e099SJoe Hershberger		after the configured retry count, the call will fail
17482c00e099SJoe Hershberger		instead of starting over.  This can be used to fail over
17492c00e099SJoe Hershberger		to Link-local IP address configuration if the DHCP server
17502c00e099SJoe Hershberger		is not available.
17512c00e099SJoe Hershberger
1752fe389a82Sstroese		CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1753fe389a82Sstroese		serverip from a DHCP server, it is possible that more
1754fe389a82Sstroese		than one DNS serverip is offered to the client.
1755fe389a82Sstroese		If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1756fe389a82Sstroese		serverip will be stored in the additional environment
1757fe389a82Sstroese		variable "dnsip2". The first DNS serverip is always
1758fe389a82Sstroese		stored in the variable "dnsip", when CONFIG_BOOTP_DNS
17591fe80d79SJon Loeliger		is defined.
1760fe389a82Sstroese
1761fe389a82Sstroese		CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1762fe389a82Sstroese		to do a dynamic update of a DNS server. To do this, they
1763fe389a82Sstroese		need the hostname of the DHCP requester.
17645d110f0aSWilson Callan		If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
17651fe80d79SJon Loeliger		of the "hostname" environment variable is passed as
17661fe80d79SJon Loeliger		option 12 to the DHCP server.
1767fe389a82Sstroese
1768d9a2f416SAras Vaichas		CONFIG_BOOTP_DHCP_REQUEST_DELAY
1769d9a2f416SAras Vaichas
1770d9a2f416SAras Vaichas		A 32bit value in microseconds for a delay between
1771d9a2f416SAras Vaichas		receiving a "DHCP Offer" and sending the "DHCP Request".
1772d9a2f416SAras Vaichas		This fixes a problem with certain DHCP servers that don't
1773d9a2f416SAras Vaichas		respond 100% of the time to a "DHCP request". E.g. On an
1774d9a2f416SAras Vaichas		AT91RM9200 processor running at 180MHz, this delay needed
1775d9a2f416SAras Vaichas		to be *at least* 15,000 usec before a Windows Server 2003
1776d9a2f416SAras Vaichas		DHCP server would reply 100% of the time. I recommend at
1777d9a2f416SAras Vaichas		least 50,000 usec to be safe. The alternative is to hope
1778d9a2f416SAras Vaichas		that one of the retries will be successful but note that
1779d9a2f416SAras Vaichas		the DHCP timeout and retry process takes a longer than
1780d9a2f416SAras Vaichas		this delay.
1781d9a2f416SAras Vaichas
1782d22c338eSJoe Hershberger - Link-local IP address negotiation:
1783d22c338eSJoe Hershberger		Negotiate with other link-local clients on the local network
1784d22c338eSJoe Hershberger		for an address that doesn't require explicit configuration.
1785d22c338eSJoe Hershberger		This is especially useful if a DHCP server cannot be guaranteed
1786d22c338eSJoe Hershberger		to exist in all environments that the device must operate.
1787d22c338eSJoe Hershberger
1788d22c338eSJoe Hershberger		See doc/README.link-local for more information.
1789d22c338eSJoe Hershberger
1790a3d991bdSwdenk - CDP Options:
1791a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID
1792a3d991bdSwdenk
1793a3d991bdSwdenk		The device id used in CDP trigger frames.
1794a3d991bdSwdenk
1795a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID_PREFIX
1796a3d991bdSwdenk
1797a3d991bdSwdenk		A two character string which is prefixed to the MAC address
1798a3d991bdSwdenk		of the device.
1799a3d991bdSwdenk
1800a3d991bdSwdenk		CONFIG_CDP_PORT_ID
1801a3d991bdSwdenk
1802a3d991bdSwdenk		A printf format string which contains the ascii name of
1803a3d991bdSwdenk		the port. Normally is set to "eth%d" which sets
180411ccc33fSMarcel Ziswiler		eth0 for the first Ethernet, eth1 for the second etc.
1805a3d991bdSwdenk
1806a3d991bdSwdenk		CONFIG_CDP_CAPABILITIES
1807a3d991bdSwdenk
1808a3d991bdSwdenk		A 32bit integer which indicates the device capabilities;
1809a3d991bdSwdenk		0x00000010 for a normal host which does not forwards.
1810a3d991bdSwdenk
1811a3d991bdSwdenk		CONFIG_CDP_VERSION
1812a3d991bdSwdenk
1813a3d991bdSwdenk		An ascii string containing the version of the software.
1814a3d991bdSwdenk
1815a3d991bdSwdenk		CONFIG_CDP_PLATFORM
1816a3d991bdSwdenk
1817a3d991bdSwdenk		An ascii string containing the name of the platform.
1818a3d991bdSwdenk
1819a3d991bdSwdenk		CONFIG_CDP_TRIGGER
1820a3d991bdSwdenk
1821a3d991bdSwdenk		A 32bit integer sent on the trigger.
1822a3d991bdSwdenk
1823a3d991bdSwdenk		CONFIG_CDP_POWER_CONSUMPTION
1824a3d991bdSwdenk
1825a3d991bdSwdenk		A 16bit integer containing the power consumption of the
1826a3d991bdSwdenk		device in .1 of milliwatts.
1827a3d991bdSwdenk
1828a3d991bdSwdenk		CONFIG_CDP_APPLIANCE_VLAN_TYPE
1829a3d991bdSwdenk
1830a3d991bdSwdenk		A byte containing the id of the VLAN.
1831a3d991bdSwdenk
183279267eddSUri Mashiach- Status LED:	CONFIG_LED_STATUS
1833c609719bSwdenk
1834c609719bSwdenk		Several configurations allow to display the current
1835c609719bSwdenk		status using a LED. For instance, the LED will blink
1836c609719bSwdenk		fast while running U-Boot code, stop blinking as
1837c609719bSwdenk		soon as a reply to a BOOTP request was received, and
1838c609719bSwdenk		start blinking slow once the Linux kernel is running
1839c609719bSwdenk		(supported by a status LED driver in the Linux
184079267eddSUri Mashiach		kernel). Defining CONFIG_LED_STATUS enables this
1841c609719bSwdenk		feature in U-Boot.
1842c609719bSwdenk
18431df7bbbaSIgor Grinberg		Additional options:
18441df7bbbaSIgor Grinberg
184579267eddSUri Mashiach		CONFIG_LED_STATUS_GPIO
18461df7bbbaSIgor Grinberg		The status LED can be connected to a GPIO pin.
18471df7bbbaSIgor Grinberg		In such cases, the gpio_led driver can be used as a
184879267eddSUri Mashiach		status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
18491df7bbbaSIgor Grinberg		to include the gpio_led driver in the U-Boot binary.
18501df7bbbaSIgor Grinberg
18519dfdcdfeSIgor Grinberg		CONFIG_GPIO_LED_INVERTED_TABLE
18529dfdcdfeSIgor Grinberg		Some GPIO connected LEDs may have inverted polarity in which
18539dfdcdfeSIgor Grinberg		case the GPIO high value corresponds to LED off state and
18549dfdcdfeSIgor Grinberg		GPIO low value corresponds to LED on state.
18559dfdcdfeSIgor Grinberg		In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
18569dfdcdfeSIgor Grinberg		with a list of GPIO LEDs that have inverted polarity.
18579dfdcdfeSIgor Grinberg
18583f4978c7SHeiko Schocher- I2C Support:	CONFIG_SYS_I2C
1859c609719bSwdenk
18603f4978c7SHeiko Schocher		This enable the NEW i2c subsystem, and will allow you to use
18613f4978c7SHeiko Schocher		i2c commands at the u-boot command line (as long as you set
18623f4978c7SHeiko Schocher		CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
18633f4978c7SHeiko Schocher		based realtime clock chips or other i2c devices. See
18643f4978c7SHeiko Schocher		common/cmd_i2c.c for a description of the command line
18653f4978c7SHeiko Schocher		interface.
18663f4978c7SHeiko Schocher
18673f4978c7SHeiko Schocher		ported i2c driver to the new framework:
1868ea818dbbSHeiko Schocher		- drivers/i2c/soft_i2c.c:
1869ea818dbbSHeiko Schocher		  - activate first bus with CONFIG_SYS_I2C_SOFT define
1870ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1871ea818dbbSHeiko Schocher		    for defining speed and slave address
1872ea818dbbSHeiko Schocher		  - activate second bus with I2C_SOFT_DECLARATIONS2 define
1873ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1874ea818dbbSHeiko Schocher		    for defining speed and slave address
1875ea818dbbSHeiko Schocher		  - activate third bus with I2C_SOFT_DECLARATIONS3 define
1876ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1877ea818dbbSHeiko Schocher		    for defining speed and slave address
1878ea818dbbSHeiko Schocher		  - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1879ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1880ea818dbbSHeiko Schocher		    for defining speed and slave address
18813f4978c7SHeiko Schocher
188200f792e0SHeiko Schocher		- drivers/i2c/fsl_i2c.c:
188300f792e0SHeiko Schocher		  - activate i2c driver with CONFIG_SYS_I2C_FSL
188400f792e0SHeiko Schocher		    define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
188500f792e0SHeiko Schocher		    offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
188600f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
188700f792e0SHeiko Schocher		    bus.
188800f792e0SHeiko Schocher		  - If your board supports a second fsl i2c bus, define
188900f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
189000f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C2_SPEED for the speed and
189100f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
189200f792e0SHeiko Schocher		    second bus.
189300f792e0SHeiko Schocher
18941f2ba722SSimon Glass		- drivers/i2c/tegra_i2c.c:
18951f2ba722SSimon Glass		  - activate this driver with CONFIG_SYS_I2C_TEGRA
18961f2ba722SSimon Glass		  - This driver adds 4 i2c buses with a fix speed from
18971f2ba722SSimon Glass		    100000 and the slave addr 0!
18981f2ba722SSimon Glass
1899880540deSDirk Eibach		- drivers/i2c/ppc4xx_i2c.c
1900880540deSDirk Eibach		  - activate this driver with CONFIG_SYS_I2C_PPC4XX
1901880540deSDirk Eibach		  - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1902880540deSDirk Eibach		  - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1903880540deSDirk Eibach
1904fac96408Strem		- drivers/i2c/i2c_mxc.c
1905fac96408Strem		  - activate this driver with CONFIG_SYS_I2C_MXC
190603544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
190703544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
190803544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
190903544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
1910fac96408Strem		  - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1911fac96408Strem		  - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1912fac96408Strem		  - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1913fac96408Strem		  - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1914fac96408Strem		  - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1915fac96408Strem		  - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
191603544c66SAlbert ARIBAUD \\(3ADEV\\)		  - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
191703544c66SAlbert ARIBAUD \\(3ADEV\\)		  - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
1918b445bbb4SJeremiah Mahler		If those defines are not set, default value is 100000
1919fac96408Strem		for speed, and 0 for slave.
1920fac96408Strem
19211086bfa9SNobuhiro Iwamatsu		- drivers/i2c/rcar_i2c.c:
19221086bfa9SNobuhiro Iwamatsu		  - activate this driver with CONFIG_SYS_I2C_RCAR
19231086bfa9SNobuhiro Iwamatsu		  - This driver adds 4 i2c buses
19241086bfa9SNobuhiro Iwamatsu
19251086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
19261086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
19271086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
19281086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
19291086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
19301086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
19311086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
19321086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
19331086bfa9SNobuhiro Iwamatsu		  - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
19341086bfa9SNobuhiro Iwamatsu
19352035d77dSNobuhiro Iwamatsu		- drivers/i2c/sh_i2c.c:
19362035d77dSNobuhiro Iwamatsu		  - activate this driver with CONFIG_SYS_I2C_SH
19372035d77dSNobuhiro Iwamatsu		  - This driver adds from 2 to 5 i2c buses
19382035d77dSNobuhiro Iwamatsu
19392035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
19402035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
19412035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
19422035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
19432035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
19442035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
19452035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
19462035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
19472035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
19482035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
1949b445bbb4SJeremiah Mahler		  - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
19502035d77dSNobuhiro Iwamatsu
19516789e84eSHeiko Schocher		- drivers/i2c/omap24xx_i2c.c
19526789e84eSHeiko Schocher		  - activate this driver with CONFIG_SYS_I2C_OMAP24XX
19536789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
19546789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
19556789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
19566789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
19576789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
19586789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
19596789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
19606789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
19616789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
19626789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
19636789e84eSHeiko Schocher
19640bdffe71SHeiko Schocher		- drivers/i2c/zynq_i2c.c
19650bdffe71SHeiko Schocher		  - activate this driver with CONFIG_SYS_I2C_ZYNQ
19660bdffe71SHeiko Schocher		  - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
19670bdffe71SHeiko Schocher		  - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
19680bdffe71SHeiko Schocher
1969e717fc6dSNaveen Krishna Ch		- drivers/i2c/s3c24x0_i2c.c:
1970e717fc6dSNaveen Krishna Ch		  - activate this driver with CONFIG_SYS_I2C_S3C24X0
1971e717fc6dSNaveen Krishna Ch		  - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1972e717fc6dSNaveen Krishna Ch		    9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1973e717fc6dSNaveen Krishna Ch		    with a fix speed from 100000 and the slave addr 0!
1974e717fc6dSNaveen Krishna Ch
1975b46226bdSDirk Eibach		- drivers/i2c/ihs_i2c.c
1976b46226bdSDirk Eibach		  - activate this driver with CONFIG_SYS_I2C_IHS
1977b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1978b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1979b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1980b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1981b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1982b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1983b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1984b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1985b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1986b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1987b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1988b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
1989071be896SDirk Eibach		  - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1990071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1991071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1992071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1993071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1994071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1995071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1996071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1997071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
1998b46226bdSDirk Eibach
19993f4978c7SHeiko Schocher		additional defines:
20003f4978c7SHeiko Schocher
20013f4978c7SHeiko Schocher		CONFIG_SYS_NUM_I2C_BUSES
2002945a18e6SSimon Glass		Hold the number of i2c buses you want to use.
20033f4978c7SHeiko Schocher
20043f4978c7SHeiko Schocher		CONFIG_SYS_I2C_DIRECT_BUS
20053f4978c7SHeiko Schocher		define this, if you don't use i2c muxes on your hardware.
20063f4978c7SHeiko Schocher		if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
20073f4978c7SHeiko Schocher		omit this define.
20083f4978c7SHeiko Schocher
20093f4978c7SHeiko Schocher		CONFIG_SYS_I2C_MAX_HOPS
20103f4978c7SHeiko Schocher		define how many muxes are maximal consecutively connected
20113f4978c7SHeiko Schocher		on one i2c bus. If you not use i2c muxes, omit this
20123f4978c7SHeiko Schocher		define.
20133f4978c7SHeiko Schocher
20143f4978c7SHeiko Schocher		CONFIG_SYS_I2C_BUSES
2015b445bbb4SJeremiah Mahler		hold a list of buses you want to use, only used if
20163f4978c7SHeiko Schocher		CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
20173f4978c7SHeiko Schocher		a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
20183f4978c7SHeiko Schocher		CONFIG_SYS_NUM_I2C_BUSES = 9:
20193f4978c7SHeiko Schocher
20203f4978c7SHeiko Schocher		 CONFIG_SYS_I2C_BUSES	{{0, {I2C_NULL_HOP}}, \
20213f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
20223f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
20233f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
20243f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
20253f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
20263f4978c7SHeiko Schocher					{1, {I2C_NULL_HOP}}, \
20273f4978c7SHeiko Schocher					{1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
20283f4978c7SHeiko Schocher					{1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
20293f4978c7SHeiko Schocher					}
20303f4978c7SHeiko Schocher
20313f4978c7SHeiko Schocher		which defines
20323f4978c7SHeiko Schocher			bus 0 on adapter 0 without a mux
2033ea818dbbSHeiko Schocher			bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2034ea818dbbSHeiko Schocher			bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2035ea818dbbSHeiko Schocher			bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2036ea818dbbSHeiko Schocher			bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2037ea818dbbSHeiko Schocher			bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
20383f4978c7SHeiko Schocher			bus 6 on adapter 1 without a mux
2039ea818dbbSHeiko Schocher			bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2040ea818dbbSHeiko Schocher			bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
20413f4978c7SHeiko Schocher
20423f4978c7SHeiko Schocher		If you do not have i2c muxes on your board, omit this define.
20433f4978c7SHeiko Schocher
2044ce3b5d69SSimon Glass- Legacy I2C Support:
2045ea818dbbSHeiko Schocher		If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2046b37c7e5eSwdenk		then the following macros need to be defined (examples are
2047b37c7e5eSwdenk		from include/configs/lwmon.h):
2048c609719bSwdenk
2049c609719bSwdenk		I2C_INIT
2050c609719bSwdenk
2051b37c7e5eSwdenk		(Optional). Any commands necessary to enable the I2C
2052c609719bSwdenk		controller or configure ports.
2053c609719bSwdenk
2054b37c7e5eSwdenk		eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |=	PB_SCL)
2055b37c7e5eSwdenk
2056c609719bSwdenk		I2C_ACTIVE
2057c609719bSwdenk
2058c609719bSwdenk		The code necessary to make the I2C data line active
2059c609719bSwdenk		(driven).  If the data line is open collector, this
2060c609719bSwdenk		define can be null.
2061c609719bSwdenk
2062b37c7e5eSwdenk		eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |=  PB_SDA)
2063b37c7e5eSwdenk
2064c609719bSwdenk		I2C_TRISTATE
2065c609719bSwdenk
2066c609719bSwdenk		The code necessary to make the I2C data line tri-stated
2067c609719bSwdenk		(inactive).  If the data line is open collector, this
2068c609719bSwdenk		define can be null.
2069c609719bSwdenk
2070b37c7e5eSwdenk		eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2071b37c7e5eSwdenk
2072c609719bSwdenk		I2C_READ
2073c609719bSwdenk
2074472d5460SYork Sun		Code that returns true if the I2C data line is high,
2075472d5460SYork Sun		false if it is low.
2076c609719bSwdenk
2077b37c7e5eSwdenk		eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2078b37c7e5eSwdenk
2079c609719bSwdenk		I2C_SDA(bit)
2080c609719bSwdenk
2081472d5460SYork Sun		If <bit> is true, sets the I2C data line high. If it
2082472d5460SYork Sun		is false, it clears it (low).
2083c609719bSwdenk
2084b37c7e5eSwdenk		eg: #define I2C_SDA(bit) \
2085b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SDA; \
2086b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SDA
2087b37c7e5eSwdenk
2088c609719bSwdenk		I2C_SCL(bit)
2089c609719bSwdenk
2090472d5460SYork Sun		If <bit> is true, sets the I2C clock line high. If it
2091472d5460SYork Sun		is false, it clears it (low).
2092c609719bSwdenk
2093b37c7e5eSwdenk		eg: #define I2C_SCL(bit) \
2094b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SCL; \
2095b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SCL
2096b37c7e5eSwdenk
2097c609719bSwdenk		I2C_DELAY
2098c609719bSwdenk
2099c609719bSwdenk		This delay is invoked four times per clock cycle so this
2100c609719bSwdenk		controls the rate of data transfer.  The data rate thus
2101b37c7e5eSwdenk		is 1 / (I2C_DELAY * 4). Often defined to be something
2102b37c7e5eSwdenk		like:
2103b37c7e5eSwdenk
2104b37c7e5eSwdenk		#define I2C_DELAY  udelay(2)
2105c609719bSwdenk
2106793b5726SMike Frysinger		CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2107793b5726SMike Frysinger
2108793b5726SMike Frysinger		If your arch supports the generic GPIO framework (asm/gpio.h),
2109793b5726SMike Frysinger		then you may alternatively define the two GPIOs that are to be
2110793b5726SMike Frysinger		used as SCL / SDA.  Any of the previous I2C_xxx macros will
2111793b5726SMike Frysinger		have GPIO-based defaults assigned to them as appropriate.
2112793b5726SMike Frysinger
2113793b5726SMike Frysinger		You should define these to the GPIO value as given directly to
2114793b5726SMike Frysinger		the generic GPIO functions.
2115793b5726SMike Frysinger
21166d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_I2C_INIT_BOARD
211747cd00faSwdenk
211847cd00faSwdenk		When a board is reset during an i2c bus transfer
211947cd00faSwdenk		chips might think that the current transfer is still
212047cd00faSwdenk		in progress. On some boards it is possible to access
212147cd00faSwdenk		the i2c SCLK line directly, either by using the
212247cd00faSwdenk		processor pin as a GPIO or by having a second pin
212347cd00faSwdenk		connected to the bus. If this option is defined a
212447cd00faSwdenk		custom i2c_init_board() routine in boards/xxx/board.c
212547cd00faSwdenk		is run early in the boot sequence.
212647cd00faSwdenk
2127bb99ad6dSBen Warren		CONFIG_I2C_MULTI_BUS
2128bb99ad6dSBen Warren
2129bb99ad6dSBen Warren		This option allows the use of multiple I2C buses, each of which
2130bb99ad6dSBen Warren		must have a controller.	 At any point in time, only one bus is
2131bb99ad6dSBen Warren		active.	 To switch to a different bus, use the 'i2c dev' command.
2132bb99ad6dSBen Warren		Note that bus numbering is zero-based.
2133bb99ad6dSBen Warren
21346d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_I2C_NOPROBES
2135bb99ad6dSBen Warren
2136bb99ad6dSBen Warren		This option specifies a list of I2C devices that will be skipped
21370f89c54bSPeter Tyser		when the 'i2c probe' command is issued.	 If CONFIG_I2C_MULTI_BUS
21380f89c54bSPeter Tyser		is set, specify a list of bus-device pairs.  Otherwise, specify
21390f89c54bSPeter Tyser		a 1D array of device addresses
2140bb99ad6dSBen Warren
2141bb99ad6dSBen Warren		e.g.
2142bb99ad6dSBen Warren			#undef	CONFIG_I2C_MULTI_BUS
21436d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			#define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2144bb99ad6dSBen Warren
2145bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on a board with one I2C bus
2146bb99ad6dSBen Warren
2147bb99ad6dSBen Warren			#define CONFIG_I2C_MULTI_BUS
2148945a18e6SSimon Glass			#define CONFIG_SYS_I2C_NOPROBES	{{0,0x50},{0,0x68},{1,0x54}}
2149bb99ad6dSBen Warren
2150bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2151bb99ad6dSBen Warren
21526d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SPD_BUS_NUM
2153be5e6181STimur Tabi
2154be5e6181STimur Tabi		If defined, then this indicates the I2C bus number for DDR SPD.
2155be5e6181STimur Tabi		If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2156be5e6181STimur Tabi
21576d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_RTC_BUS_NUM
21580dc018ecSStefan Roese
21590dc018ecSStefan Roese		If defined, then this indicates the I2C bus number for the RTC.
21600dc018ecSStefan Roese		If not defined, then U-Boot assumes that RTC is on I2C bus 0.
21610dc018ecSStefan Roese
21622ac6985aSAndrew Dyer		CONFIG_SOFT_I2C_READ_REPEATED_START
21632ac6985aSAndrew Dyer
21642ac6985aSAndrew Dyer		defining this will force the i2c_read() function in
21652ac6985aSAndrew Dyer		the soft_i2c driver to perform an I2C repeated start
21662ac6985aSAndrew Dyer		between writing the address pointer and reading the
21672ac6985aSAndrew Dyer		data.  If this define is omitted the default behaviour
21682ac6985aSAndrew Dyer		of doing a stop-start sequence will be used.  Most I2C
21692ac6985aSAndrew Dyer		devices can use either method, but some require one or
21702ac6985aSAndrew Dyer		the other.
2171be5e6181STimur Tabi
2172c609719bSwdenk- SPI Support:	CONFIG_SPI
2173c609719bSwdenk
2174c609719bSwdenk		Enables SPI driver (so far only tested with
2175c609719bSwdenk		SPI EEPROM, also an instance works with Crystal A/D and
2176c609719bSwdenk		D/As on the SACSng board)
2177c609719bSwdenk
21786639562eSYoshihiro Shimoda		CONFIG_SH_SPI
21796639562eSYoshihiro Shimoda
21806639562eSYoshihiro Shimoda		Enables the driver for SPI controller on SuperH. Currently
21816639562eSYoshihiro Shimoda		only SH7757 is supported.
21826639562eSYoshihiro Shimoda
2183c609719bSwdenk		CONFIG_SOFT_SPI
2184c609719bSwdenk
2185c609719bSwdenk		Enables a software (bit-bang) SPI driver rather than
2186c609719bSwdenk		using hardware support. This is a general purpose
2187c609719bSwdenk		driver that only requires three general I/O port pins
2188c609719bSwdenk		(two outputs, one input) to function. If this is
2189c609719bSwdenk		defined, the board configuration must define several
2190c609719bSwdenk		SPI configuration items (port pins to use, etc). For
2191c609719bSwdenk		an example, see include/configs/sacsng.h.
2192c609719bSwdenk
219304a9e118SBen Warren		CONFIG_HARD_SPI
219404a9e118SBen Warren
219504a9e118SBen Warren		Enables a hardware SPI driver for general-purpose reads
219604a9e118SBen Warren		and writes.  As with CONFIG_SOFT_SPI, the board configuration
219704a9e118SBen Warren		must define a list of chip-select function pointers.
219804a9e118SBen Warren		Currently supported on some MPC8xxx processors.	 For an
219904a9e118SBen Warren		example, see include/configs/mpc8349emds.h.
220004a9e118SBen Warren
220138254f45SGuennadi Liakhovetski		CONFIG_MXC_SPI
220238254f45SGuennadi Liakhovetski
220338254f45SGuennadi Liakhovetski		Enables the driver for the SPI controllers on i.MX and MXC
22042e3cd1cdSFabio Estevam		SoCs. Currently i.MX31/35/51 are supported.
220538254f45SGuennadi Liakhovetski
2206f659b573SHeiko Schocher		CONFIG_SYS_SPI_MXC_WAIT
2207f659b573SHeiko Schocher		Timeout for waiting until spi transfer completed.
2208f659b573SHeiko Schocher		default: (CONFIG_SYS_HZ/100)     /* 10 ms */
2209f659b573SHeiko Schocher
22100133502eSMatthias Fuchs- FPGA Support: CONFIG_FPGA
22110133502eSMatthias Fuchs
22120133502eSMatthias Fuchs		Enables FPGA subsystem.
22130133502eSMatthias Fuchs
22140133502eSMatthias Fuchs		CONFIG_FPGA_<vendor>
22150133502eSMatthias Fuchs
22160133502eSMatthias Fuchs		Enables support for specific chip vendors.
22170133502eSMatthias Fuchs		(ALTERA, XILINX)
22180133502eSMatthias Fuchs
22190133502eSMatthias Fuchs		CONFIG_FPGA_<family>
22200133502eSMatthias Fuchs
22210133502eSMatthias Fuchs		Enables support for FPGA family.
22220133502eSMatthias Fuchs		(SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
22230133502eSMatthias Fuchs
22240133502eSMatthias Fuchs		CONFIG_FPGA_COUNT
2225c609719bSwdenk
2226c609719bSwdenk		Specify the number of FPGA devices to support.
2227c609719bSwdenk
22286d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_PROG_FEEDBACK
2229c609719bSwdenk
2230c609719bSwdenk		Enable printing of hash marks during FPGA configuration.
2231c609719bSwdenk
22326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_BUSY
2233c609719bSwdenk
2234c609719bSwdenk		Enable checks on FPGA configuration interface busy
2235c609719bSwdenk		status by the configuration function. This option
2236c609719bSwdenk		will require a board or device specific function to
2237c609719bSwdenk		be written.
2238c609719bSwdenk
2239c609719bSwdenk		CONFIG_FPGA_DELAY
2240c609719bSwdenk
2241c609719bSwdenk		If defined, a function that provides delays in the FPGA
2242c609719bSwdenk		configuration driver.
2243c609719bSwdenk
22446d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_CTRLC
2245c609719bSwdenk		Allow Control-C to interrupt FPGA configuration
2246c609719bSwdenk
22476d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_ERROR
2248c609719bSwdenk
2249c609719bSwdenk		Check for configuration errors during FPGA bitfile
2250c609719bSwdenk		loading. For example, abort during Virtex II
2251c609719bSwdenk		configuration if the INIT_B line goes low (which
2252c609719bSwdenk		indicated a CRC error).
2253c609719bSwdenk
22546d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_INIT
2255c609719bSwdenk
2256b445bbb4SJeremiah Mahler		Maximum time to wait for the INIT_B line to de-assert
2257b445bbb4SJeremiah Mahler		after PROB_B has been de-asserted during a Virtex II
2258c609719bSwdenk		FPGA configuration sequence. The default time is 500
225911ccc33fSMarcel Ziswiler		ms.
2260c609719bSwdenk
22616d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_BUSY
2262c609719bSwdenk
2263b445bbb4SJeremiah Mahler		Maximum time to wait for BUSY to de-assert during
226411ccc33fSMarcel Ziswiler		Virtex II FPGA configuration. The default is 5 ms.
2265c609719bSwdenk
22666d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_CONFIG
2267c609719bSwdenk
2268c609719bSwdenk		Time to wait after FPGA configuration. The default is
226911ccc33fSMarcel Ziswiler		200 ms.
2270c609719bSwdenk
2271c609719bSwdenk- Configuration Management:
2272b2b8a696SStefan Roese		CONFIG_BUILD_TARGET
2273b2b8a696SStefan Roese
2274b2b8a696SStefan Roese		Some SoCs need special image types (e.g. U-Boot binary
2275b2b8a696SStefan Roese		with a special header) as build targets. By defining
2276b2b8a696SStefan Roese		CONFIG_BUILD_TARGET in the SoC / board header, this
2277b2b8a696SStefan Roese		special image will be automatically built upon calling
22786de80f21SSimon Glass		make / buildman.
2279b2b8a696SStefan Roese
2280c609719bSwdenk		CONFIG_IDENT_STRING
2281c609719bSwdenk
2282c609719bSwdenk		If defined, this string will be added to the U-Boot
2283c609719bSwdenk		version information (U_BOOT_VERSION)
2284c609719bSwdenk
2285c609719bSwdenk- Vendor Parameter Protection:
2286c609719bSwdenk
2287c609719bSwdenk		U-Boot considers the values of the environment
2288c609719bSwdenk		variables "serial#" (Board Serial Number) and
22897152b1d0Swdenk		"ethaddr" (Ethernet Address) to be parameters that
2290c609719bSwdenk		are set once by the board vendor / manufacturer, and
2291c609719bSwdenk		protects these variables from casual modification by
2292c609719bSwdenk		the user. Once set, these variables are read-only,
2293c609719bSwdenk		and write or delete attempts are rejected. You can
229411ccc33fSMarcel Ziswiler		change this behaviour:
2295c609719bSwdenk
2296c609719bSwdenk		If CONFIG_ENV_OVERWRITE is #defined in your config
2297c609719bSwdenk		file, the write protection for vendor parameters is
229847cd00faSwdenk		completely disabled. Anybody can change or delete
2299c609719bSwdenk		these parameters.
2300c609719bSwdenk
230192ac5208SJoe Hershberger		Alternatively, if you define _both_ an ethaddr in the
230292ac5208SJoe Hershberger		default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
230311ccc33fSMarcel Ziswiler		Ethernet address is installed in the environment,
2304c609719bSwdenk		which can be changed exactly ONCE by the user. [The
2305c609719bSwdenk		serial# is unaffected by this, i. e. it remains
2306c609719bSwdenk		read-only.]
2307c609719bSwdenk
23082598090bSJoe Hershberger		The same can be accomplished in a more flexible way
23092598090bSJoe Hershberger		for any variable by configuring the type of access
23102598090bSJoe Hershberger		to allow for those variables in the ".flags" variable
23112598090bSJoe Hershberger		or define CONFIG_ENV_FLAGS_LIST_STATIC.
23122598090bSJoe Hershberger
2313c609719bSwdenk- Protected RAM:
2314c609719bSwdenk		CONFIG_PRAM
2315c609719bSwdenk
2316c609719bSwdenk		Define this variable to enable the reservation of
2317c609719bSwdenk		"protected RAM", i. e. RAM which is not overwritten
2318c609719bSwdenk		by U-Boot. Define CONFIG_PRAM to hold the number of
2319c609719bSwdenk		kB you want to reserve for pRAM. You can overwrite
2320c609719bSwdenk		this default value by defining an environment
2321c609719bSwdenk		variable "pram" to the number of kB you want to
2322c609719bSwdenk		reserve. Note that the board info structure will
2323c609719bSwdenk		still show the full amount of RAM. If pRAM is
2324c609719bSwdenk		reserved, a new environment variable "mem" will
2325c609719bSwdenk		automatically be defined to hold the amount of
2326c609719bSwdenk		remaining RAM in a form that can be passed as boot
2327c609719bSwdenk		argument to Linux, for instance like that:
2328c609719bSwdenk
2329fe126d8bSWolfgang Denk			setenv bootargs ... mem=\${mem}
2330c609719bSwdenk			saveenv
2331c609719bSwdenk
2332c609719bSwdenk		This way you can tell Linux not to use this memory,
2333c609719bSwdenk		either, which results in a memory region that will
2334c609719bSwdenk		not be affected by reboots.
2335c609719bSwdenk
2336c609719bSwdenk		*WARNING* If your board configuration uses automatic
2337c609719bSwdenk		detection of the RAM size, you must make sure that
2338c609719bSwdenk		this memory test is non-destructive. So far, the
2339c609719bSwdenk		following board configurations are known to be
2340c609719bSwdenk		"pRAM-clean":
2341c609719bSwdenk
23425b8e76c3SHeiko Schocher			IVMS8, IVML24, SPD8xx,
23431b0757ecSWolfgang Denk			HERMES, IP860, RPXlite, LWMON,
23442eb48ff7SHeiko Schocher			FLAGADM
2345c609719bSwdenk
234640fef049SGabe Black- Access to physical memory region (> 4GB)
234740fef049SGabe Black		Some basic support is provided for operations on memory not
234840fef049SGabe Black		normally accessible to U-Boot - e.g. some architectures
234940fef049SGabe Black		support access to more than 4GB of memory on 32-bit
235040fef049SGabe Black		machines using physical address extension or similar.
235140fef049SGabe Black		Define CONFIG_PHYSMEM to access this basic support, which
235240fef049SGabe Black		currently only supports clearing the memory.
235340fef049SGabe Black
2354c609719bSwdenk- Error Recovery:
2355c609719bSwdenk		CONFIG_PANIC_HANG
2356c609719bSwdenk
2357c609719bSwdenk		Define this variable to stop the system in case of a
2358c609719bSwdenk		fatal error, so that you have to reset it manually.
2359c609719bSwdenk		This is probably NOT a good idea for an embedded
236011ccc33fSMarcel Ziswiler		system where you want the system to reboot
2361c609719bSwdenk		automatically as fast as possible, but it may be
2362c609719bSwdenk		useful during development since you can try to debug
2363c609719bSwdenk		the conditions that lead to the situation.
2364c609719bSwdenk
2365c609719bSwdenk		CONFIG_NET_RETRY_COUNT
2366c609719bSwdenk
2367c609719bSwdenk		This variable defines the number of retries for
2368c609719bSwdenk		network operations like ARP, RARP, TFTP, or BOOTP
2369c609719bSwdenk		before giving up the operation. If not defined, a
2370c609719bSwdenk		default value of 5 is used.
2371c609719bSwdenk
237240cb90eeSGuennadi Liakhovetski		CONFIG_ARP_TIMEOUT
237340cb90eeSGuennadi Liakhovetski
237440cb90eeSGuennadi Liakhovetski		Timeout waiting for an ARP reply in milliseconds.
237540cb90eeSGuennadi Liakhovetski
237648a3e999STetsuyuki Kobayashi		CONFIG_NFS_TIMEOUT
237748a3e999STetsuyuki Kobayashi
237848a3e999STetsuyuki Kobayashi		Timeout in milliseconds used in NFS protocol.
237948a3e999STetsuyuki Kobayashi		If you encounter "ERROR: Cannot umount" in nfs command,
238048a3e999STetsuyuki Kobayashi		try longer timeout such as
238148a3e999STetsuyuki Kobayashi		#define CONFIG_NFS_TIMEOUT 10000UL
238248a3e999STetsuyuki Kobayashi
2383c609719bSwdenk- Command Interpreter:
23848078f1a5SWolfgang Denk		CONFIG_AUTO_COMPLETE
238504a85b3bSwdenk
238604a85b3bSwdenk		Enable auto completion of commands using TAB.
238704a85b3bSwdenk
23886d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_PROMPT_HUSH_PS2
2389c609719bSwdenk
2390c609719bSwdenk		This defines the secondary prompt string, which is
2391c609719bSwdenk		printed when the command interpreter needs more input
2392c609719bSwdenk		to complete a command. Usually "> ".
2393c609719bSwdenk
2394c609719bSwdenk	Note:
2395c609719bSwdenk
2396c609719bSwdenk		In the current implementation, the local variables
2397c609719bSwdenk		space and global environment variables space are
2398c609719bSwdenk		separated. Local variables are those you define by
23993b57fe0aSwdenk		simply typing `name=value'. To access a local
2400c609719bSwdenk		variable later on, you have write `$name' or
24013b57fe0aSwdenk		`${name}'; to execute the contents of a variable
24023b57fe0aSwdenk		directly type `$name' at the command prompt.
2403c609719bSwdenk
2404c609719bSwdenk		Global environment variables are those you use
2405c609719bSwdenk		setenv/printenv to work with. To run a command stored
2406c609719bSwdenk		in such a variable, you need to use the run command,
2407c609719bSwdenk		and you must not use the '$' sign to access them.
2408c609719bSwdenk
2409c609719bSwdenk		To store commands and special characters in a
2410c609719bSwdenk		variable, please use double quotation marks
2411c609719bSwdenk		surrounding the whole text of the variable, instead
2412c609719bSwdenk		of the backslashes before semicolons and special
2413c609719bSwdenk		symbols.
2414c609719bSwdenk
2415b445bbb4SJeremiah Mahler- Command Line Editing and History:
2416aa0c71acSWolfgang Denk		CONFIG_CMDLINE_EDITING
2417aa0c71acSWolfgang Denk
241811ccc33fSMarcel Ziswiler		Enable editing and History functions for interactive
2419aa0c71acSWolfgang Denk		command line input operations
2420aa0c71acSWolfgang Denk
2421f3b267b3SMarek Vasut- Command Line PS1/PS2 support:
2422f3b267b3SMarek Vasut		CONFIG_CMDLINE_PS_SUPPORT
2423f3b267b3SMarek Vasut
2424f3b267b3SMarek Vasut		Enable support for changing the command prompt string
2425f3b267b3SMarek Vasut		at run-time. Only static string is supported so far.
2426f3b267b3SMarek Vasut		The string is obtained from environment variables PS1
2427f3b267b3SMarek Vasut		and PS2.
2428f3b267b3SMarek Vasut
2429a8c7c708Swdenk- Default Environment:
2430c609719bSwdenk		CONFIG_EXTRA_ENV_SETTINGS
2431c609719bSwdenk
2432c609719bSwdenk		Define this to contain any number of null terminated
2433c609719bSwdenk		strings (variable = value pairs) that will be part of
24347152b1d0Swdenk		the default environment compiled into the boot image.
24352262cfeeSwdenk
2436c609719bSwdenk		For example, place something like this in your
2437c609719bSwdenk		board's config file:
2438c609719bSwdenk
2439c609719bSwdenk		#define CONFIG_EXTRA_ENV_SETTINGS \
2440c609719bSwdenk			"myvar1=value1\0" \
2441c609719bSwdenk			"myvar2=value2\0"
2442c609719bSwdenk
2443c609719bSwdenk		Warning: This method is based on knowledge about the
2444c609719bSwdenk		internal format how the environment is stored by the
24452262cfeeSwdenk		U-Boot code. This is NOT an official, exported
2446c609719bSwdenk		interface! Although it is unlikely that this format
24477152b1d0Swdenk		will change soon, there is no guarantee either.
2448c609719bSwdenk		You better know what you are doing here.
2449c609719bSwdenk
2450c609719bSwdenk		Note: overly (ab)use of the default environment is
2451c609719bSwdenk		discouraged. Make sure to check other ways to preset
245274de7aefSWolfgang Denk		the environment like the "source" command or the
2453c609719bSwdenk		boot command first.
2454c609719bSwdenk
24555e724ca2SStephen Warren		CONFIG_ENV_VARS_UBOOT_CONFIG
24565e724ca2SStephen Warren
24575e724ca2SStephen Warren		Define this in order to add variables describing the
24585e724ca2SStephen Warren		U-Boot build configuration to the default environment.
24595e724ca2SStephen Warren		These will be named arch, cpu, board, vendor, and soc.
24605e724ca2SStephen Warren
24615e724ca2SStephen Warren		Enabling this option will cause the following to be defined:
24625e724ca2SStephen Warren
24635e724ca2SStephen Warren		- CONFIG_SYS_ARCH
24645e724ca2SStephen Warren		- CONFIG_SYS_CPU
24655e724ca2SStephen Warren		- CONFIG_SYS_BOARD
24665e724ca2SStephen Warren		- CONFIG_SYS_VENDOR
24675e724ca2SStephen Warren		- CONFIG_SYS_SOC
24685e724ca2SStephen Warren
24697e27f89fSTom Rini		CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
24707e27f89fSTom Rini
24717e27f89fSTom Rini		Define this in order to add variables describing certain
24727e27f89fSTom Rini		run-time determined information about the hardware to the
24737e27f89fSTom Rini		environment.  These will be named board_name, board_rev.
24747e27f89fSTom Rini
247506fd8538SSimon Glass		CONFIG_DELAY_ENVIRONMENT
247606fd8538SSimon Glass
247706fd8538SSimon Glass		Normally the environment is loaded when the board is
2478b445bbb4SJeremiah Mahler		initialised so that it is available to U-Boot. This inhibits
247906fd8538SSimon Glass		that so that the environment is not available until
248006fd8538SSimon Glass		explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
248106fd8538SSimon Glass		this is instead controlled by the value of
248206fd8538SSimon Glass		/config/load-environment.
248306fd8538SSimon Glass
2484a8c7c708Swdenk- DataFlash Support:
24852abbe075Swdenk		CONFIG_HAS_DATAFLASH
24862abbe075Swdenk
24872abbe075Swdenk		Defining this option enables DataFlash features and
24882abbe075Swdenk		allows to read/write in Dataflash via the standard
24892abbe075Swdenk		commands cp, md...
24902abbe075Swdenk
2491f61ec45eSEric Nelson- Serial Flash support
2492f61ec45eSEric Nelson		CONFIG_CMD_SF
2493f61ec45eSEric Nelson
2494f61ec45eSEric Nelson		Defining this option enables SPI flash commands
2495f61ec45eSEric Nelson		'sf probe/read/write/erase/update'.
2496f61ec45eSEric Nelson
2497f61ec45eSEric Nelson		Usage requires an initial 'probe' to define the serial
2498f61ec45eSEric Nelson		flash parameters, followed by read/write/erase/update
2499f61ec45eSEric Nelson		commands.
2500f61ec45eSEric Nelson
2501f61ec45eSEric Nelson		The following defaults may be provided by the platform
2502f61ec45eSEric Nelson		to handle the common case when only a single serial
2503f61ec45eSEric Nelson		flash is present on the system.
2504f61ec45eSEric Nelson
2505f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_BUS		Bus identifier
2506f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_CS		Chip-select
2507f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_MODE 		(see include/spi.h)
2508f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_SPEED		in Hz
2509f61ec45eSEric Nelson
251024007273SSimon Glass		CONFIG_CMD_SF_TEST
251124007273SSimon Glass
251224007273SSimon Glass		Define this option to include a destructive SPI flash
251324007273SSimon Glass		test ('sf test').
251424007273SSimon Glass
25153f85ce27Swdenk- SystemACE Support:
25163f85ce27Swdenk		CONFIG_SYSTEMACE
25173f85ce27Swdenk
25183f85ce27Swdenk		Adding this option adds support for Xilinx SystemACE
25193f85ce27Swdenk		chips attached via some sort of local bus. The address
252011ccc33fSMarcel Ziswiler		of the chip must also be defined in the
25216d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SYSTEMACE_BASE macro. For example:
25223f85ce27Swdenk
25233f85ce27Swdenk		#define CONFIG_SYSTEMACE
25246d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		#define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
25253f85ce27Swdenk
25263f85ce27Swdenk		When SystemACE support is added, the "ace" device type
25273f85ce27Swdenk		becomes available to the fat commands, i.e. fatls.
25283f85ce27Swdenk
2529ecb0ccd9SWolfgang Denk- TFTP Fixed UDP Port:
2530ecb0ccd9SWolfgang Denk		CONFIG_TFTP_PORT
2531ecb0ccd9SWolfgang Denk
253228cb9375SWolfgang Denk		If this is defined, the environment variable tftpsrcp
2533ecb0ccd9SWolfgang Denk		is used to supply the TFTP UDP source port value.
253428cb9375SWolfgang Denk		If tftpsrcp isn't defined, the normal pseudo-random port
2535ecb0ccd9SWolfgang Denk		number generator is used.
2536ecb0ccd9SWolfgang Denk
253728cb9375SWolfgang Denk		Also, the environment variable tftpdstp is used to supply
253828cb9375SWolfgang Denk		the TFTP UDP destination port value.  If tftpdstp isn't
253928cb9375SWolfgang Denk		defined, the normal port 69 is used.
254028cb9375SWolfgang Denk
254128cb9375SWolfgang Denk		The purpose for tftpsrcp is to allow a TFTP server to
2542ecb0ccd9SWolfgang Denk		blindly start the TFTP transfer using the pre-configured
2543ecb0ccd9SWolfgang Denk		target IP address and UDP port. This has the effect of
2544ecb0ccd9SWolfgang Denk		"punching through" the (Windows XP) firewall, allowing
2545ecb0ccd9SWolfgang Denk		the remainder of the TFTP transfer to proceed normally.
2546ecb0ccd9SWolfgang Denk		A better solution is to properly configure the firewall,
2547ecb0ccd9SWolfgang Denk		but sometimes that is not allowed.
2548ecb0ccd9SWolfgang Denk
25499e50c406SHeiko Schocher- bootcount support:
25509e50c406SHeiko Schocher		CONFIG_BOOTCOUNT_LIMIT
25519e50c406SHeiko Schocher
25529e50c406SHeiko Schocher		This enables the bootcounter support, see:
25539e50c406SHeiko Schocher		http://www.denx.de/wiki/DULG/UBootBootCountLimit
25549e50c406SHeiko Schocher
25559e50c406SHeiko Schocher		CONFIG_AT91SAM9XE
25569e50c406SHeiko Schocher		enable special bootcounter support on at91sam9xe based boards.
25579e50c406SHeiko Schocher		CONFIG_SOC_DA8XX
25589e50c406SHeiko Schocher		enable special bootcounter support on da850 based boards.
25599e50c406SHeiko Schocher		CONFIG_BOOTCOUNT_RAM
25609e50c406SHeiko Schocher		enable support for the bootcounter in RAM
25619e50c406SHeiko Schocher		CONFIG_BOOTCOUNT_I2C
25629e50c406SHeiko Schocher		enable support for the bootcounter on an i2c (like RTC) device.
25639e50c406SHeiko Schocher			CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
25649e50c406SHeiko Schocher			CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
25659e50c406SHeiko Schocher						    the bootcounter.
25669e50c406SHeiko Schocher			CONFIG_BOOTCOUNT_ALEN = address len
256719c402afSSimon Glass
2568a8c7c708Swdenk- Show boot progress:
2569c609719bSwdenk		CONFIG_SHOW_BOOT_PROGRESS
2570c609719bSwdenk
2571c609719bSwdenk		Defining this option allows to add some board-
2572c609719bSwdenk		specific code (calling a user-provided function
2573c609719bSwdenk		"show_boot_progress(int)") that enables you to show
2574c609719bSwdenk		the system's boot progress on some display (for
2575c609719bSwdenk		example, some LED's) on your board. At the moment,
2576c609719bSwdenk		the following checkpoints are implemented:
2577c609719bSwdenk
257894fd1316SSimon Glass
25791372cce2SMarian BalakowiczLegacy uImage format:
25801372cce2SMarian Balakowicz
2581c609719bSwdenk  Arg	Where			When
2582c609719bSwdenk    1	common/cmd_bootm.c	before attempting to boot an image
2583c609719bSwdenk   -1	common/cmd_bootm.c	Image header has bad	 magic number
2584c609719bSwdenk    2	common/cmd_bootm.c	Image header has correct magic number
2585c609719bSwdenk   -2	common/cmd_bootm.c	Image header has bad	 checksum
2586c609719bSwdenk    3	common/cmd_bootm.c	Image header has correct checksum
2587c609719bSwdenk   -3	common/cmd_bootm.c	Image data   has bad	 checksum
2588c609719bSwdenk    4	common/cmd_bootm.c	Image data   has correct checksum
2589c609719bSwdenk   -4	common/cmd_bootm.c	Image is for unsupported architecture
2590c609719bSwdenk    5	common/cmd_bootm.c	Architecture check OK
25911372cce2SMarian Balakowicz   -5	common/cmd_bootm.c	Wrong Image Type (not kernel, multi)
2592c609719bSwdenk    6	common/cmd_bootm.c	Image Type check OK
2593c609719bSwdenk   -6	common/cmd_bootm.c	gunzip uncompression error
2594c609719bSwdenk   -7	common/cmd_bootm.c	Unimplemented compression type
2595c609719bSwdenk    7	common/cmd_bootm.c	Uncompression OK
25961372cce2SMarian Balakowicz    8	common/cmd_bootm.c	No uncompress/copy overwrite error
2597c609719bSwdenk   -9	common/cmd_bootm.c	Unsupported OS (not Linux, BSD, VxWorks, QNX)
25981372cce2SMarian Balakowicz
25991372cce2SMarian Balakowicz    9	common/image.c		Start initial ramdisk verification
26001372cce2SMarian Balakowicz  -10	common/image.c		Ramdisk header has bad	   magic number
26011372cce2SMarian Balakowicz  -11	common/image.c		Ramdisk header has bad	   checksum
26021372cce2SMarian Balakowicz   10	common/image.c		Ramdisk header is OK
26031372cce2SMarian Balakowicz  -12	common/image.c		Ramdisk data   has bad	   checksum
26041372cce2SMarian Balakowicz   11	common/image.c		Ramdisk data   has correct checksum
26051372cce2SMarian Balakowicz   12	common/image.c		Ramdisk verification complete, start loading
260611ccc33fSMarcel Ziswiler  -13	common/image.c		Wrong Image Type (not PPC Linux ramdisk)
26071372cce2SMarian Balakowicz   13	common/image.c		Start multifile image verification
26081372cce2SMarian Balakowicz   14	common/image.c		No initial ramdisk, no multifile, continue.
26091372cce2SMarian Balakowicz
2610ea0364f1SPeter Tyser   15	arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2611c609719bSwdenk
2612a47a12beSStefan Roese  -30	arch/powerpc/lib/board.c	Fatal error, hang the system
261363e73c9aSwdenk  -31	post/post.c		POST test failed, detected by post_output_backlog()
261463e73c9aSwdenk  -32	post/post.c		POST test failed, detected by post_run_single()
261563e73c9aSwdenk
2616566a494fSHeiko Schocher   34	common/cmd_doc.c	before loading a Image from a DOC device
2617566a494fSHeiko Schocher  -35	common/cmd_doc.c	Bad usage of "doc" command
2618566a494fSHeiko Schocher   35	common/cmd_doc.c	correct usage of "doc" command
2619566a494fSHeiko Schocher  -36	common/cmd_doc.c	No boot device
2620566a494fSHeiko Schocher   36	common/cmd_doc.c	correct boot device
2621566a494fSHeiko Schocher  -37	common/cmd_doc.c	Unknown Chip ID on boot device
2622566a494fSHeiko Schocher   37	common/cmd_doc.c	correct chip ID found, device available
2623566a494fSHeiko Schocher  -38	common/cmd_doc.c	Read Error on boot device
2624566a494fSHeiko Schocher   38	common/cmd_doc.c	reading Image header from DOC device OK
2625566a494fSHeiko Schocher  -39	common/cmd_doc.c	Image header has bad magic number
2626566a494fSHeiko Schocher   39	common/cmd_doc.c	Image header has correct magic number
2627566a494fSHeiko Schocher  -40	common/cmd_doc.c	Error reading Image from DOC device
2628566a494fSHeiko Schocher   40	common/cmd_doc.c	Image header has correct magic number
2629566a494fSHeiko Schocher   41	common/cmd_ide.c	before loading a Image from a IDE device
2630566a494fSHeiko Schocher  -42	common/cmd_ide.c	Bad usage of "ide" command
2631566a494fSHeiko Schocher   42	common/cmd_ide.c	correct usage of "ide" command
2632566a494fSHeiko Schocher  -43	common/cmd_ide.c	No boot device
2633566a494fSHeiko Schocher   43	common/cmd_ide.c	boot device found
2634566a494fSHeiko Schocher  -44	common/cmd_ide.c	Device not available
2635566a494fSHeiko Schocher   44	common/cmd_ide.c	Device available
2636566a494fSHeiko Schocher  -45	common/cmd_ide.c	wrong partition selected
2637566a494fSHeiko Schocher   45	common/cmd_ide.c	partition selected
2638566a494fSHeiko Schocher  -46	common/cmd_ide.c	Unknown partition table
2639566a494fSHeiko Schocher   46	common/cmd_ide.c	valid partition table found
2640566a494fSHeiko Schocher  -47	common/cmd_ide.c	Invalid partition type
2641566a494fSHeiko Schocher   47	common/cmd_ide.c	correct partition type
2642566a494fSHeiko Schocher  -48	common/cmd_ide.c	Error reading Image Header on boot device
2643566a494fSHeiko Schocher   48	common/cmd_ide.c	reading Image Header from IDE device OK
2644566a494fSHeiko Schocher  -49	common/cmd_ide.c	Image header has bad magic number
2645566a494fSHeiko Schocher   49	common/cmd_ide.c	Image header has correct magic number
2646566a494fSHeiko Schocher  -50	common/cmd_ide.c	Image header has bad	 checksum
2647566a494fSHeiko Schocher   50	common/cmd_ide.c	Image header has correct checksum
2648566a494fSHeiko Schocher  -51	common/cmd_ide.c	Error reading Image from IDE device
2649566a494fSHeiko Schocher   51	common/cmd_ide.c	reading Image from IDE device OK
2650566a494fSHeiko Schocher   52	common/cmd_nand.c	before loading a Image from a NAND device
2651566a494fSHeiko Schocher  -53	common/cmd_nand.c	Bad usage of "nand" command
2652566a494fSHeiko Schocher   53	common/cmd_nand.c	correct usage of "nand" command
2653566a494fSHeiko Schocher  -54	common/cmd_nand.c	No boot device
2654566a494fSHeiko Schocher   54	common/cmd_nand.c	boot device found
2655566a494fSHeiko Schocher  -55	common/cmd_nand.c	Unknown Chip ID on boot device
2656566a494fSHeiko Schocher   55	common/cmd_nand.c	correct chip ID found, device available
2657566a494fSHeiko Schocher  -56	common/cmd_nand.c	Error reading Image Header on boot device
2658566a494fSHeiko Schocher   56	common/cmd_nand.c	reading Image Header from NAND device OK
2659566a494fSHeiko Schocher  -57	common/cmd_nand.c	Image header has bad magic number
2660566a494fSHeiko Schocher   57	common/cmd_nand.c	Image header has correct magic number
2661566a494fSHeiko Schocher  -58	common/cmd_nand.c	Error reading Image from NAND device
2662566a494fSHeiko Schocher   58	common/cmd_nand.c	reading Image from NAND device OK
2663c609719bSwdenk
2664566a494fSHeiko Schocher  -60	common/env_common.c	Environment has a bad CRC, using default
2665c609719bSwdenk
2666566a494fSHeiko Schocher   64	net/eth.c		starting with Ethernet configuration.
2667566a494fSHeiko Schocher  -64	net/eth.c		no Ethernet found.
2668566a494fSHeiko Schocher   65	net/eth.c		Ethernet found.
2669206c60cbSwdenk
2670566a494fSHeiko Schocher  -80	common/cmd_net.c	usage wrong
2671bc0571fcSJoe Hershberger   80	common/cmd_net.c	before calling net_loop()
2672bc0571fcSJoe Hershberger  -81	common/cmd_net.c	some error in net_loop() occurred
2673bc0571fcSJoe Hershberger   81	common/cmd_net.c	net_loop() back without error
2674566a494fSHeiko Schocher  -82	common/cmd_net.c	size == 0 (File with size 0 loaded)
2675566a494fSHeiko Schocher   82	common/cmd_net.c	trying automatic boot
267674de7aefSWolfgang Denk   83	common/cmd_net.c	running "source" command
267774de7aefSWolfgang Denk  -83	common/cmd_net.c	some error in automatic boot or "source" command
2678566a494fSHeiko Schocher   84	common/cmd_net.c	end without errors
2679c609719bSwdenk
26801372cce2SMarian BalakowiczFIT uImage format:
26811372cce2SMarian Balakowicz
26821372cce2SMarian Balakowicz  Arg	Where			When
26831372cce2SMarian Balakowicz  100	common/cmd_bootm.c	Kernel FIT Image has correct format
26841372cce2SMarian Balakowicz -100	common/cmd_bootm.c	Kernel FIT Image has incorrect format
26851372cce2SMarian Balakowicz  101	common/cmd_bootm.c	No Kernel subimage unit name, using configuration
26861372cce2SMarian Balakowicz -101	common/cmd_bootm.c	Can't get configuration for kernel subimage
26871372cce2SMarian Balakowicz  102	common/cmd_bootm.c	Kernel unit name specified
26881372cce2SMarian Balakowicz -103	common/cmd_bootm.c	Can't get kernel subimage node offset
2689f773bea8SMarian Balakowicz  103	common/cmd_bootm.c	Found configuration node
26901372cce2SMarian Balakowicz  104	common/cmd_bootm.c	Got kernel subimage node offset
26911372cce2SMarian Balakowicz -104	common/cmd_bootm.c	Kernel subimage hash verification failed
26921372cce2SMarian Balakowicz  105	common/cmd_bootm.c	Kernel subimage hash verification OK
26931372cce2SMarian Balakowicz -105	common/cmd_bootm.c	Kernel subimage is for unsupported architecture
26941372cce2SMarian Balakowicz  106	common/cmd_bootm.c	Architecture check OK
269511ccc33fSMarcel Ziswiler -106	common/cmd_bootm.c	Kernel subimage has wrong type
269611ccc33fSMarcel Ziswiler  107	common/cmd_bootm.c	Kernel subimage type OK
26971372cce2SMarian Balakowicz -107	common/cmd_bootm.c	Can't get kernel subimage data/size
26981372cce2SMarian Balakowicz  108	common/cmd_bootm.c	Got kernel subimage data/size
26991372cce2SMarian Balakowicz -108	common/cmd_bootm.c	Wrong image type (not legacy, FIT)
27001372cce2SMarian Balakowicz -109	common/cmd_bootm.c	Can't get kernel subimage type
27011372cce2SMarian Balakowicz -110	common/cmd_bootm.c	Can't get kernel subimage comp
27021372cce2SMarian Balakowicz -111	common/cmd_bootm.c	Can't get kernel subimage os
27031372cce2SMarian Balakowicz -112	common/cmd_bootm.c	Can't get kernel subimage load address
27041372cce2SMarian Balakowicz -113	common/cmd_bootm.c	Image uncompress/copy overwrite error
27051372cce2SMarian Balakowicz
27061372cce2SMarian Balakowicz  120	common/image.c		Start initial ramdisk verification
27071372cce2SMarian Balakowicz -120	common/image.c		Ramdisk FIT image has incorrect format
27081372cce2SMarian Balakowicz  121	common/image.c		Ramdisk FIT image has correct format
270911ccc33fSMarcel Ziswiler  122	common/image.c		No ramdisk subimage unit name, using configuration
27101372cce2SMarian Balakowicz -122	common/image.c		Can't get configuration for ramdisk subimage
27111372cce2SMarian Balakowicz  123	common/image.c		Ramdisk unit name specified
27121372cce2SMarian Balakowicz -124	common/image.c		Can't get ramdisk subimage node offset
27131372cce2SMarian Balakowicz  125	common/image.c		Got ramdisk subimage node offset
27141372cce2SMarian Balakowicz -125	common/image.c		Ramdisk subimage hash verification failed
27151372cce2SMarian Balakowicz  126	common/image.c		Ramdisk subimage hash verification OK
27161372cce2SMarian Balakowicz -126	common/image.c		Ramdisk subimage for unsupported architecture
27171372cce2SMarian Balakowicz  127	common/image.c		Architecture check OK
27181372cce2SMarian Balakowicz -127	common/image.c		Can't get ramdisk subimage data/size
27191372cce2SMarian Balakowicz  128	common/image.c		Got ramdisk subimage data/size
27201372cce2SMarian Balakowicz  129	common/image.c		Can't get ramdisk load address
27211372cce2SMarian Balakowicz -129	common/image.c		Got ramdisk load address
27221372cce2SMarian Balakowicz
272311ccc33fSMarcel Ziswiler -130	common/cmd_doc.c	Incorrect FIT image format
27241372cce2SMarian Balakowicz  131	common/cmd_doc.c	FIT image format OK
27251372cce2SMarian Balakowicz
272611ccc33fSMarcel Ziswiler -140	common/cmd_ide.c	Incorrect FIT image format
27271372cce2SMarian Balakowicz  141	common/cmd_ide.c	FIT image format OK
27281372cce2SMarian Balakowicz
272911ccc33fSMarcel Ziswiler -150	common/cmd_nand.c	Incorrect FIT image format
27301372cce2SMarian Balakowicz  151	common/cmd_nand.c	FIT image format OK
27311372cce2SMarian Balakowicz
273221d29f7fSHeiko Schocher- legacy image format:
273321d29f7fSHeiko Schocher		CONFIG_IMAGE_FORMAT_LEGACY
273421d29f7fSHeiko Schocher		enables the legacy image format support in U-Boot.
273521d29f7fSHeiko Schocher
273621d29f7fSHeiko Schocher		Default:
273721d29f7fSHeiko Schocher		enabled if CONFIG_FIT_SIGNATURE is not defined.
273821d29f7fSHeiko Schocher
273921d29f7fSHeiko Schocher		CONFIG_DISABLE_IMAGE_LEGACY
274021d29f7fSHeiko Schocher		disable the legacy image format
274121d29f7fSHeiko Schocher
274221d29f7fSHeiko Schocher		This define is introduced, as the legacy image format is
274321d29f7fSHeiko Schocher		enabled per default for backward compatibility.
274421d29f7fSHeiko Schocher
27454cf2609bSWolfgang Denk- Standalone program support:
27464cf2609bSWolfgang Denk		CONFIG_STANDALONE_LOAD_ADDR
27474cf2609bSWolfgang Denk
27486feff899SWolfgang Denk		This option defines a board specific value for the
27496feff899SWolfgang Denk		address where standalone program gets loaded, thus
27506feff899SWolfgang Denk		overwriting the architecture dependent default
27514cf2609bSWolfgang Denk		settings.
27524cf2609bSWolfgang Denk
27534cf2609bSWolfgang Denk- Frame Buffer Address:
27544cf2609bSWolfgang Denk		CONFIG_FB_ADDR
27554cf2609bSWolfgang Denk
27564cf2609bSWolfgang Denk		Define CONFIG_FB_ADDR if you want to use specific
275744a53b57SWolfgang Denk		address for frame buffer.  This is typically the case
275844a53b57SWolfgang Denk		when using a graphics controller has separate video
275944a53b57SWolfgang Denk		memory.  U-Boot will then place the frame buffer at
276044a53b57SWolfgang Denk		the given address instead of dynamically reserving it
276144a53b57SWolfgang Denk		in system RAM by calling lcd_setmem(), which grabs
276244a53b57SWolfgang Denk		the memory for the frame buffer depending on the
276344a53b57SWolfgang Denk		configured panel size.
27644cf2609bSWolfgang Denk
27654cf2609bSWolfgang Denk		Please see board_init_f function.
27664cf2609bSWolfgang Denk
2767cccfc2abSDetlev Zundel- Automatic software updates via TFTP server
2768cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP
2769cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP_CNT_MAX
2770cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP_MSEC_MAX
2771cccfc2abSDetlev Zundel
2772cccfc2abSDetlev Zundel		These options enable and control the auto-update feature;
2773cccfc2abSDetlev Zundel		for a more detailed description refer to doc/README.update.
2774cccfc2abSDetlev Zundel
2775cccfc2abSDetlev Zundel- MTD Support (mtdparts command, UBI support)
2776cccfc2abSDetlev Zundel		CONFIG_MTD_DEVICE
2777cccfc2abSDetlev Zundel
2778cccfc2abSDetlev Zundel		Adds the MTD device infrastructure from the Linux kernel.
2779cccfc2abSDetlev Zundel		Needed for mtdparts command support.
2780cccfc2abSDetlev Zundel
2781cccfc2abSDetlev Zundel		CONFIG_MTD_PARTITIONS
2782cccfc2abSDetlev Zundel
2783cccfc2abSDetlev Zundel		Adds the MTD partitioning infrastructure from the Linux
2784cccfc2abSDetlev Zundel		kernel. Needed for UBI support.
2785cccfc2abSDetlev Zundel
278670c219cdSJoe Hershberger- UBI support
2787147162daSJoe Hershberger		CONFIG_UBI_SILENCE_MSG
2788147162daSJoe Hershberger
2789147162daSJoe Hershberger		Make the verbose messages from UBI stop printing.  This leaves
2790147162daSJoe Hershberger		warnings and errors enabled.
2791147162daSJoe Hershberger
2792ff94bc40SHeiko Schocher
2793ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_WL_THRESHOLD
2794ff94bc40SHeiko Schocher		This parameter defines the maximum difference between the highest
2795ff94bc40SHeiko Schocher		erase counter value and the lowest erase counter value of eraseblocks
2796ff94bc40SHeiko Schocher		of UBI devices. When this threshold is exceeded, UBI starts performing
2797ff94bc40SHeiko Schocher		wear leveling by means of moving data from eraseblock with low erase
2798ff94bc40SHeiko Schocher		counter to eraseblocks with high erase counter.
2799ff94bc40SHeiko Schocher
2800ff94bc40SHeiko Schocher		The default value should be OK for SLC NAND flashes, NOR flashes and
2801ff94bc40SHeiko Schocher		other flashes which have eraseblock life-cycle 100000 or more.
2802ff94bc40SHeiko Schocher		However, in case of MLC NAND flashes which typically have eraseblock
2803ff94bc40SHeiko Schocher		life-cycle less than 10000, the threshold should be lessened (e.g.,
2804ff94bc40SHeiko Schocher		to 128 or 256, although it does not have to be power of 2).
2805ff94bc40SHeiko Schocher
2806ff94bc40SHeiko Schocher		default: 4096
2807ff94bc40SHeiko Schocher
2808ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_BEB_LIMIT
2809ff94bc40SHeiko Schocher		This option specifies the maximum bad physical eraseblocks UBI
2810ff94bc40SHeiko Schocher		expects on the MTD device (per 1024 eraseblocks). If the
2811ff94bc40SHeiko Schocher		underlying flash does not admit of bad eraseblocks (e.g. NOR
2812ff94bc40SHeiko Schocher		flash), this value is ignored.
2813ff94bc40SHeiko Schocher
2814ff94bc40SHeiko Schocher		NAND datasheets often specify the minimum and maximum NVM
2815ff94bc40SHeiko Schocher		(Number of Valid Blocks) for the flashes' endurance lifetime.
2816ff94bc40SHeiko Schocher		The maximum expected bad eraseblocks per 1024 eraseblocks
2817ff94bc40SHeiko Schocher		then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2818ff94bc40SHeiko Schocher		which gives 20 for most NANDs (MaxNVB is basically the total
2819ff94bc40SHeiko Schocher		count of eraseblocks on the chip).
2820ff94bc40SHeiko Schocher
2821ff94bc40SHeiko Schocher		To put it differently, if this value is 20, UBI will try to
2822ff94bc40SHeiko Schocher		reserve about 1.9% of physical eraseblocks for bad blocks
2823ff94bc40SHeiko Schocher		handling. And that will be 1.9% of eraseblocks on the entire
2824ff94bc40SHeiko Schocher		NAND chip, not just the MTD partition UBI attaches. This means
2825ff94bc40SHeiko Schocher		that if you have, say, a NAND flash chip admits maximum 40 bad
2826ff94bc40SHeiko Schocher		eraseblocks, and it is split on two MTD partitions of the same
2827ff94bc40SHeiko Schocher		size, UBI will reserve 40 eraseblocks when attaching a
2828ff94bc40SHeiko Schocher		partition.
2829ff94bc40SHeiko Schocher
2830ff94bc40SHeiko Schocher		default: 20
2831ff94bc40SHeiko Schocher
2832ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_FASTMAP
2833ff94bc40SHeiko Schocher		Fastmap is a mechanism which allows attaching an UBI device
2834ff94bc40SHeiko Schocher		in nearly constant time. Instead of scanning the whole MTD device it
2835ff94bc40SHeiko Schocher		only has to locate a checkpoint (called fastmap) on the device.
2836ff94bc40SHeiko Schocher		The on-flash fastmap contains all information needed to attach
2837ff94bc40SHeiko Schocher		the device. Using fastmap makes only sense on large devices where
2838ff94bc40SHeiko Schocher		attaching by scanning takes long. UBI will not automatically install
2839ff94bc40SHeiko Schocher		a fastmap on old images, but you can set the UBI parameter
2840ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2841ff94bc40SHeiko Schocher		that fastmap-enabled images are still usable with UBI implementations
2842ff94bc40SHeiko Schocher		without	fastmap support. On typical flash devices the whole fastmap
2843ff94bc40SHeiko Schocher		fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2844ff94bc40SHeiko Schocher
2845ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2846ff94bc40SHeiko Schocher		Set this parameter to enable fastmap automatically on images
2847ff94bc40SHeiko Schocher		without a fastmap.
2848ff94bc40SHeiko Schocher		default: 0
2849ff94bc40SHeiko Schocher
28500195a7bbSHeiko Schocher		CONFIG_MTD_UBI_FM_DEBUG
28510195a7bbSHeiko Schocher		Enable UBI fastmap debug
28520195a7bbSHeiko Schocher		default: 0
28530195a7bbSHeiko Schocher
285470c219cdSJoe Hershberger- UBIFS support
2855147162daSJoe Hershberger		CONFIG_UBIFS_SILENCE_MSG
2856147162daSJoe Hershberger
2857147162daSJoe Hershberger		Make the verbose messages from UBIFS stop printing.  This leaves
2858147162daSJoe Hershberger		warnings and errors enabled.
2859147162daSJoe Hershberger
28606a11cf48SDaniel Schwierzeck- SPL framework
28616a11cf48SDaniel Schwierzeck		CONFIG_SPL
28626a11cf48SDaniel Schwierzeck		Enable building of SPL globally.
28636a11cf48SDaniel Schwierzeck
286495579793STom Rini		CONFIG_SPL_LDSCRIPT
286595579793STom Rini		LDSCRIPT for linking the SPL binary.
286695579793STom Rini
28676ebc3461SAlbert ARIBAUD		CONFIG_SPL_MAX_FOOTPRINT
28686ebc3461SAlbert ARIBAUD		Maximum size in memory allocated to the SPL, BSS included.
28696ebc3461SAlbert ARIBAUD		When defined, the linker checks that the actual memory
28706ebc3461SAlbert ARIBAUD		used by SPL from _start to __bss_end does not exceed it.
28718960af8bSAlbert ARIBAUD		CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
28726ebc3461SAlbert ARIBAUD		must not be both defined at the same time.
28736ebc3461SAlbert ARIBAUD
287495579793STom Rini		CONFIG_SPL_MAX_SIZE
28756ebc3461SAlbert ARIBAUD		Maximum size of the SPL image (text, data, rodata, and
28766ebc3461SAlbert ARIBAUD		linker lists sections), BSS excluded.
28776ebc3461SAlbert ARIBAUD		When defined, the linker checks that the actual size does
28786ebc3461SAlbert ARIBAUD		not exceed it.
287995579793STom Rini
28806a11cf48SDaniel Schwierzeck		CONFIG_SPL_TEXT_BASE
28816a11cf48SDaniel Schwierzeck		TEXT_BASE for linking the SPL binary.
28826a11cf48SDaniel Schwierzeck
288394a45bb1SScott Wood		CONFIG_SPL_RELOC_TEXT_BASE
288494a45bb1SScott Wood		Address to relocate to.  If unspecified, this is equal to
288594a45bb1SScott Wood		CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
288694a45bb1SScott Wood
288795579793STom Rini		CONFIG_SPL_BSS_START_ADDR
288895579793STom Rini		Link address for the BSS within the SPL binary.
288995579793STom Rini
289095579793STom Rini		CONFIG_SPL_BSS_MAX_SIZE
28916ebc3461SAlbert ARIBAUD		Maximum size in memory allocated to the SPL BSS.
28926ebc3461SAlbert ARIBAUD		When defined, the linker checks that the actual memory used
28936ebc3461SAlbert ARIBAUD		by SPL from __bss_start to __bss_end does not exceed it.
28948960af8bSAlbert ARIBAUD		CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
28956ebc3461SAlbert ARIBAUD		must not be both defined at the same time.
289695579793STom Rini
289795579793STom Rini		CONFIG_SPL_STACK
289895579793STom Rini		Adress of the start of the stack SPL will use
289995579793STom Rini
29008c80eb3bSAlbert ARIBAUD \(3ADEV\)		CONFIG_SPL_PANIC_ON_RAW_IMAGE
29018c80eb3bSAlbert ARIBAUD \(3ADEV\)		When defined, SPL will panic() if the image it has
29028c80eb3bSAlbert ARIBAUD \(3ADEV\)		loaded does not have a signature.
29038c80eb3bSAlbert ARIBAUD \(3ADEV\)		Defining this is useful when code which loads images
29048c80eb3bSAlbert ARIBAUD \(3ADEV\)		in SPL cannot guarantee that absolutely all read errors
29058c80eb3bSAlbert ARIBAUD \(3ADEV\)		will be caught.
29068c80eb3bSAlbert ARIBAUD \(3ADEV\)		An example is the LPC32XX MLC NAND driver, which will
29078c80eb3bSAlbert ARIBAUD \(3ADEV\)		consider that a completely unreadable NAND block is bad,
29088c80eb3bSAlbert ARIBAUD \(3ADEV\)		and thus should be skipped silently.
29098c80eb3bSAlbert ARIBAUD \(3ADEV\)
291094a45bb1SScott Wood		CONFIG_SPL_RELOC_STACK
291194a45bb1SScott Wood		Adress of the start of the stack SPL will use after
291294a45bb1SScott Wood		relocation.  If unspecified, this is equal to
291394a45bb1SScott Wood		CONFIG_SPL_STACK.
291494a45bb1SScott Wood
291595579793STom Rini		CONFIG_SYS_SPL_MALLOC_START
291695579793STom Rini		Starting address of the malloc pool used in SPL.
29179ac4fc82SFabio Estevam		When this option is set the full malloc is used in SPL and
29189ac4fc82SFabio Estevam		it is set up by spl_init() and before that, the simple malloc()
29199ac4fc82SFabio Estevam		can be used if CONFIG_SYS_MALLOC_F is defined.
292095579793STom Rini
292195579793STom Rini		CONFIG_SYS_SPL_MALLOC_SIZE
292295579793STom Rini		The size of the malloc pool used in SPL.
29236a11cf48SDaniel Schwierzeck
292447f7bcaeSTom Rini		CONFIG_SPL_FRAMEWORK
292547f7bcaeSTom Rini		Enable the SPL framework under common/.  This framework
292647f7bcaeSTom Rini		supports MMC, NAND and YMODEM loading of U-Boot and NAND
292747f7bcaeSTom Rini		NAND loading of the Linux Kernel.
292847f7bcaeSTom Rini
29299607faf2STom Rini		CONFIG_SPL_OS_BOOT
29309607faf2STom Rini		Enable booting directly to an OS from SPL.
29319607faf2STom Rini		See also: doc/README.falcon
29329607faf2STom Rini
2933861a86f4STom Rini		CONFIG_SPL_DISPLAY_PRINT
2934861a86f4STom Rini		For ARM, enable an optional function to print more information
2935861a86f4STom Rini		about the running system.
2936861a86f4STom Rini
29374b919725SScott Wood		CONFIG_SPL_INIT_MINIMAL
29384b919725SScott Wood		Arch init code should be built for a very small image
29394b919725SScott Wood
2940b97300b6SPaul Kocialkowski		CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2941b97300b6SPaul Kocialkowski		Partition on the MMC to load U-Boot from when the MMC is being
2942b97300b6SPaul Kocialkowski		used in raw mode
2943b97300b6SPaul Kocialkowski
29442b75b0adSPeter Korsgaard		CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
29452b75b0adSPeter Korsgaard		Sector to load kernel uImage from when MMC is being
29462b75b0adSPeter Korsgaard		used in raw mode (for Falcon mode)
29472b75b0adSPeter Korsgaard
29482b75b0adSPeter Korsgaard		CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
29492b75b0adSPeter Korsgaard		CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
29502b75b0adSPeter Korsgaard		Sector and number of sectors to load kernel argument
29512b75b0adSPeter Korsgaard		parameters from when MMC is being used in raw mode
29522b75b0adSPeter Korsgaard		(for falcon mode)
29532b75b0adSPeter Korsgaard
2954e2ccdf89SPaul Kocialkowski		CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2955e2ccdf89SPaul Kocialkowski		Partition on the MMC to load U-Boot from when the MMC is being
2956e2ccdf89SPaul Kocialkowski		used in fs mode
2957e2ccdf89SPaul Kocialkowski
2958fae81c72SGuillaume GARDET		CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2959fae81c72SGuillaume GARDET		Filename to read to load U-Boot when reading from filesystem
2960fae81c72SGuillaume GARDET
2961fae81c72SGuillaume GARDET		CONFIG_SPL_FS_LOAD_KERNEL_NAME
29627ad2cc79SPeter Korsgaard		Filename to read to load kernel uImage when reading
2963fae81c72SGuillaume GARDET		from filesystem (for Falcon mode)
29647ad2cc79SPeter Korsgaard
2965fae81c72SGuillaume GARDET		CONFIG_SPL_FS_LOAD_ARGS_NAME
29667ad2cc79SPeter Korsgaard		Filename to read to load kernel argument parameters
2967fae81c72SGuillaume GARDET		when reading from filesystem (for Falcon mode)
29687ad2cc79SPeter Korsgaard
296906f60ae3SScott Wood		CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
297006f60ae3SScott Wood		Set this for NAND SPL on PPC mpc83xx targets, so that
297106f60ae3SScott Wood		start.S waits for the rest of the SPL to load before
297206f60ae3SScott Wood		continuing (the hardware starts execution after just
297306f60ae3SScott Wood		loading the first page rather than the full 4K).
297406f60ae3SScott Wood
2975651fcf60SPrabhakar Kushwaha		CONFIG_SPL_SKIP_RELOCATE
2976651fcf60SPrabhakar Kushwaha		Avoid SPL relocation
2977651fcf60SPrabhakar Kushwaha
29786f2f01b9SScott Wood		CONFIG_SPL_NAND_BASE
29796f2f01b9SScott Wood		Include nand_base.c in the SPL.  Requires
29806f2f01b9SScott Wood		CONFIG_SPL_NAND_DRIVERS.
29816f2f01b9SScott Wood
29826f2f01b9SScott Wood		CONFIG_SPL_NAND_DRIVERS
29836f2f01b9SScott Wood		SPL uses normal NAND drivers, not minimal drivers.
29846f2f01b9SScott Wood
29856f2f01b9SScott Wood		CONFIG_SPL_NAND_ECC
29866f2f01b9SScott Wood		Include standard software ECC in the SPL
29876f2f01b9SScott Wood
298895579793STom Rini		CONFIG_SPL_NAND_SIMPLE
29897d4b7955SScott Wood		Support for NAND boot using simple NAND drivers that
29907d4b7955SScott Wood		expose the cmd_ctrl() interface.
299195579793STom Rini
29926f4e7d3cSThomas Gleixner		CONFIG_SPL_UBI
29936f4e7d3cSThomas Gleixner		Support for a lightweight UBI (fastmap) scanner and
29946f4e7d3cSThomas Gleixner		loader
29956f4e7d3cSThomas Gleixner
29960c3117b1SHeiko Schocher		CONFIG_SPL_NAND_RAW_ONLY
29970c3117b1SHeiko Schocher		Support to boot only raw u-boot.bin images. Use this only
29980c3117b1SHeiko Schocher		if you need to save space.
29990c3117b1SHeiko Schocher
30007c8eea59SYing Zhang		CONFIG_SPL_COMMON_INIT_DDR
30017c8eea59SYing Zhang		Set for common ddr init with serial presence detect in
30027c8eea59SYing Zhang		SPL binary.
30037c8eea59SYing Zhang
300495579793STom Rini		CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
300595579793STom Rini		CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
300695579793STom Rini		CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
300795579793STom Rini		CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
300895579793STom Rini		CONFIG_SYS_NAND_ECCBYTES
300995579793STom Rini		Defines the size and behavior of the NAND that SPL uses
30107d4b7955SScott Wood		to read U-Boot
301195579793STom Rini
3012fbe76ae4SPrabhakar Kushwaha		CONFIG_SPL_NAND_BOOT
3013fbe76ae4SPrabhakar Kushwaha		Add support NAND boot
3014fbe76ae4SPrabhakar Kushwaha
301595579793STom Rini		CONFIG_SYS_NAND_U_BOOT_OFFS
30167d4b7955SScott Wood		Location in NAND to read U-Boot from
30177d4b7955SScott Wood
30187d4b7955SScott Wood		CONFIG_SYS_NAND_U_BOOT_DST
30197d4b7955SScott Wood		Location in memory to load U-Boot to
30207d4b7955SScott Wood
30217d4b7955SScott Wood		CONFIG_SYS_NAND_U_BOOT_SIZE
30227d4b7955SScott Wood		Size of image to load
302395579793STom Rini
302495579793STom Rini		CONFIG_SYS_NAND_U_BOOT_START
30257d4b7955SScott Wood		Entry point in loaded image to jump to
302695579793STom Rini
302795579793STom Rini		CONFIG_SYS_NAND_HW_ECC_OOBFIRST
302895579793STom Rini		Define this if you need to first read the OOB and then the
3029b445bbb4SJeremiah Mahler		data. This is used, for example, on davinci platforms.
303095579793STom Rini
303195579793STom Rini		CONFIG_SPL_OMAP3_ID_NAND
303295579793STom Rini		Support for an OMAP3-specific set of functions to return the
303395579793STom Rini		ID and MFR of the first attached NAND chip, if present.
303495579793STom Rini
3035c57b953dSPavel Machek		CONFIG_SPL_RAM_DEVICE
3036c57b953dSPavel Machek		Support for running image already present in ram, in SPL binary
3037c57b953dSPavel Machek
303874752baaSScott Wood		CONFIG_SPL_PAD_TO
30396113d3f2SBenoît Thébaudeau		Image offset to which the SPL should be padded before appending
30406113d3f2SBenoît Thébaudeau		the SPL payload. By default, this is defined as
30416113d3f2SBenoît Thébaudeau		CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
30426113d3f2SBenoît Thébaudeau		CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
30436113d3f2SBenoît Thébaudeau		payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
304474752baaSScott Wood
3045ca2fca22SScott Wood		CONFIG_SPL_TARGET
3046ca2fca22SScott Wood		Final target image containing SPL and payload.  Some SPLs
3047ca2fca22SScott Wood		use an arch-specific makefile fragment instead, for
3048ca2fca22SScott Wood		example if more than one image needs to be produced.
3049ca2fca22SScott Wood
305087ebee39SSimon Glass		CONFIG_FIT_SPL_PRINT
305187ebee39SSimon Glass		Printing information about a FIT image adds quite a bit of
305287ebee39SSimon Glass		code to SPL. So this is normally disabled in SPL. Use this
305387ebee39SSimon Glass		option to re-enable it. This will affect the output of the
305487ebee39SSimon Glass		bootm command when booting a FIT image.
305587ebee39SSimon Glass
30563aa29de0SYing Zhang- TPL framework
30573aa29de0SYing Zhang		CONFIG_TPL
30583aa29de0SYing Zhang		Enable building of TPL globally.
30593aa29de0SYing Zhang
30603aa29de0SYing Zhang		CONFIG_TPL_PAD_TO
30613aa29de0SYing Zhang		Image offset to which the TPL should be padded before appending
30623aa29de0SYing Zhang		the TPL payload. By default, this is defined as
30633aa29de0SYing Zhang		CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
30643aa29de0SYing Zhang		CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
30653aa29de0SYing Zhang		payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
30663aa29de0SYing Zhang
3067a8c7c708Swdenk- Interrupt support (PPC):
3068a8c7c708Swdenk
3069a8c7c708Swdenk		There are common interrupt_init() and timer_interrupt()
3070a8c7c708Swdenk		for all PPC archs. interrupt_init() calls interrupt_init_cpu()
307111ccc33fSMarcel Ziswiler		for CPU specific initialization. interrupt_init_cpu()
3072a8c7c708Swdenk		should set decrementer_count to appropriate value. If
307311ccc33fSMarcel Ziswiler		CPU resets decrementer automatically after interrupt
3074a8c7c708Swdenk		(ppc4xx) it should set decrementer_count to zero.
307511ccc33fSMarcel Ziswiler		timer_interrupt() calls timer_interrupt_cpu() for CPU
3076a8c7c708Swdenk		specific handling. If board has watchdog / status_led
3077a8c7c708Swdenk		/ other_activity_monitor it works automatically from
3078a8c7c708Swdenk		general timer_interrupt().
3079a8c7c708Swdenk
3080c609719bSwdenk
30819660e442SHelmut RaigerBoard initialization settings:
30829660e442SHelmut Raiger------------------------------
30839660e442SHelmut Raiger
30849660e442SHelmut RaigerDuring Initialization u-boot calls a number of board specific functions
30859660e442SHelmut Raigerto allow the preparation of board specific prerequisites, e.g. pin setup
30869660e442SHelmut Raigerbefore drivers are initialized. To enable these callbacks the
30879660e442SHelmut Raigerfollowing configuration macros have to be defined. Currently this is
30889660e442SHelmut Raigerarchitecture specific, so please check arch/your_architecture/lib/board.c
30899660e442SHelmut Raigertypically in board_init_f() and board_init_r().
30909660e442SHelmut Raiger
30919660e442SHelmut Raiger- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
30929660e442SHelmut Raiger- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
30939660e442SHelmut Raiger- CONFIG_BOARD_LATE_INIT: Call board_late_init()
30949660e442SHelmut Raiger- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3095c609719bSwdenk
3096c609719bSwdenkConfiguration Settings:
3097c609719bSwdenk-----------------------
3098c609719bSwdenk
30994d1fd7f1SYork Sun- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
31004d1fd7f1SYork Sun		Optionally it can be defined to support 64-bit memory commands.
31014d1fd7f1SYork Sun
31026d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3103c609719bSwdenk		undefine this when you're short of memory.
3104c609719bSwdenk
31052fb2604dSPeter Tyser- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
31062fb2604dSPeter Tyser		width of the commands listed in the 'help' command output.
31072fb2604dSPeter Tyser
31086d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PROMPT:	This is what U-Boot prints on the console to
3109c609719bSwdenk		prompt for user input.
3110c609719bSwdenk
31116d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CBSIZE:	Buffer size for input from the Console
3112c609719bSwdenk
31136d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PBSIZE:	Buffer size for Console output
3114c609719bSwdenk
31156d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAXARGS:	max. Number of arguments accepted for monitor commands
3116c609719bSwdenk
31176d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3118c609719bSwdenk		the application (usually a Linux kernel) when it is
3119c609719bSwdenk		booted
3120c609719bSwdenk
31216d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BAUDRATE_TABLE:
3122c609719bSwdenk		List of legal baudrate settings for this board.
3123c609719bSwdenk
31246d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3125c609719bSwdenk		Begin and End addresses of the area used by the
3126c609719bSwdenk		simple memory test.
3127c609719bSwdenk
31286d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_ALT_MEMTEST:
3129c609719bSwdenk		Enable an alternate, more extensive memory test.
3130c609719bSwdenk
31316d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MEMTEST_SCRATCH:
31325f535fe1Swdenk		Scratch address used by the alternate memory test
31335f535fe1Swdenk		You only need to set this if address zero isn't writeable
31345f535fe1Swdenk
3135e8149522SYork Sun- CONFIG_SYS_MEM_RESERVE_SECURE
3136e61a7534SYork Sun		Only implemented for ARMv8 for now.
3137e8149522SYork Sun		If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
3138e8149522SYork Sun		is substracted from total RAM and won't be reported to OS.
3139e8149522SYork Sun		This memory can be used as secure memory. A variable
3140e61a7534SYork Sun		gd->arch.secure_ram is used to track the location. In systems
3141e8149522SYork Sun		the RAM base is not zero, or RAM is divided into banks,
3142e8149522SYork Sun		this variable needs to be recalcuated to get the address.
3143e8149522SYork Sun
3144aabd7ddbSYork Sun- CONFIG_SYS_MEM_TOP_HIDE:
31456d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
314614f73ca6SStefan Roese		this specified memory area will get subtracted from the top
314711ccc33fSMarcel Ziswiler		(end) of RAM and won't get "touched" at all by U-Boot. By
314814f73ca6SStefan Roese		fixing up gd->ram_size the Linux kernel should gets passed
314914f73ca6SStefan Roese		the now "corrected" memory size and won't touch it either.
315014f73ca6SStefan Roese		This should work for arch/ppc and arch/powerpc. Only Linux
31515e12e75dSStefan Roese		board ports in arch/powerpc with bootwrapper support that
315214f73ca6SStefan Roese		recalculate the memory size from the SDRAM controller setup
31535e12e75dSStefan Roese		will have to get fixed in Linux additionally.
315414f73ca6SStefan Roese
315514f73ca6SStefan Roese		This option can be used as a workaround for the 440EPx/GRx
315614f73ca6SStefan Roese		CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
315714f73ca6SStefan Roese		be touched.
315814f73ca6SStefan Roese
315914f73ca6SStefan Roese		WARNING: Please make sure that this value is a multiple of
316014f73ca6SStefan Roese		the Linux page size (normally 4k). If this is not the case,
316114f73ca6SStefan Roese		then the end address of the Linux memory will be located at a
316214f73ca6SStefan Roese		non page size aligned address and this could cause major
316314f73ca6SStefan Roese		problems.
316414f73ca6SStefan Roese
31656d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_LOADS_BAUD_CHANGE:
3166c609719bSwdenk		Enable temporary baudrate change while serial download
3167c609719bSwdenk
31686d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SDRAM_BASE:
3169c609719bSwdenk		Physical start address of SDRAM. _Must_ be 0 here.
3170c609719bSwdenk
31716d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_BASE:
3172c609719bSwdenk		Physical start address of Flash memory.
3173c609719bSwdenk
31746d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MONITOR_BASE:
3175c609719bSwdenk		Physical start address of boot monitor code (set by
3176c609719bSwdenk		make config files to be same as the text base address
317714d0a02aSWolfgang Denk		(CONFIG_SYS_TEXT_BASE) used when linking) - same as
31786d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FLASH_BASE when booting from flash.
3179c609719bSwdenk
31806d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MONITOR_LEN:
31813b57fe0aSwdenk		Size of memory reserved for monitor code, used to
31823b57fe0aSwdenk		determine _at_compile_time_ (!) if the environment is
31833b57fe0aSwdenk		embedded within the U-Boot image, or in a separate
31843b57fe0aSwdenk		flash sector.
3185c609719bSwdenk
31866d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MALLOC_LEN:
3187c609719bSwdenk		Size of DRAM reserved for malloc() use.
3188c609719bSwdenk
3189d59476b6SSimon Glass- CONFIG_SYS_MALLOC_F_LEN
3190d59476b6SSimon Glass		Size of the malloc() pool for use before relocation. If
3191d59476b6SSimon Glass		this is defined, then a very simple malloc() implementation
3192d59476b6SSimon Glass		will become available before relocation. The address is just
3193d59476b6SSimon Glass		below the global data, and the stack is moved down to make
3194d59476b6SSimon Glass		space.
3195d59476b6SSimon Glass
3196d59476b6SSimon Glass		This feature allocates regions with increasing addresses
3197d59476b6SSimon Glass		within the region. calloc() is supported, but realloc()
3198d59476b6SSimon Glass		is not available. free() is supported but does nothing.
3199b445bbb4SJeremiah Mahler		The memory will be freed (or in fact just forgotten) when
3200d59476b6SSimon Glass		U-Boot relocates itself.
3201d59476b6SSimon Glass
320238687ae6SSimon Glass- CONFIG_SYS_MALLOC_SIMPLE
320338687ae6SSimon Glass		Provides a simple and small malloc() and calloc() for those
320438687ae6SSimon Glass		boards which do not use the full malloc in SPL (which is
320538687ae6SSimon Glass		enabled with CONFIG_SYS_SPL_MALLOC_START).
320638687ae6SSimon Glass
32071dfdd9baSThierry Reding- CONFIG_SYS_NONCACHED_MEMORY:
32081dfdd9baSThierry Reding		Size of non-cached memory area. This area of memory will be
32091dfdd9baSThierry Reding		typically located right below the malloc() area and mapped
32101dfdd9baSThierry Reding		uncached in the MMU. This is useful for drivers that would
32111dfdd9baSThierry Reding		otherwise require a lot of explicit cache maintenance. For
32121dfdd9baSThierry Reding		some drivers it's also impossible to properly maintain the
32131dfdd9baSThierry Reding		cache. For example if the regions that need to be flushed
32141dfdd9baSThierry Reding		are not a multiple of the cache-line size, *and* padding
32151dfdd9baSThierry Reding		cannot be allocated between the regions to align them (i.e.
32161dfdd9baSThierry Reding		if the HW requires a contiguous array of regions, and the
32171dfdd9baSThierry Reding		size of each region is not cache-aligned), then a flush of
32181dfdd9baSThierry Reding		one region may result in overwriting data that hardware has
32191dfdd9baSThierry Reding		written to another region in the same cache-line. This can
32201dfdd9baSThierry Reding		happen for example in network drivers where descriptors for
32211dfdd9baSThierry Reding		buffers are typically smaller than the CPU cache-line (e.g.
32221dfdd9baSThierry Reding		16 bytes vs. 32 or 64 bytes).
32231dfdd9baSThierry Reding
32241dfdd9baSThierry Reding		Non-cached memory is only supported on 32-bit ARM at present.
32251dfdd9baSThierry Reding
32266d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BOOTM_LEN:
322715940c9aSStefan Roese		Normally compressed uImages are limited to an
322815940c9aSStefan Roese		uncompressed size of 8 MBytes. If this is not enough,
32296d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		you can define CONFIG_SYS_BOOTM_LEN in your board config file
323015940c9aSStefan Roese		to adjust this setting to your needs.
3231c609719bSwdenk
32326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BOOTMAPSZ:
3233c609719bSwdenk		Maximum size of memory mapped by the startup code of
3234c609719bSwdenk		the Linux kernel; all data that must be processed by
32357d721e34SBartlomiej Sieka		the Linux kernel (bd_info, boot arguments, FDT blob if
32367d721e34SBartlomiej Sieka		used) must be put below this limit, unless "bootm_low"
32371bce2aebSRobert P. J. Day		environment variable is defined and non-zero. In such case
32387d721e34SBartlomiej Sieka		all data for the Linux kernel must be between "bootm_low"
3239c3624e6eSGrant Likely		and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.	 The environment
3240c3624e6eSGrant Likely		variable "bootm_mapsize" will override the value of
3241c3624e6eSGrant Likely		CONFIG_SYS_BOOTMAPSZ.  If CONFIG_SYS_BOOTMAPSZ is undefined,
3242c3624e6eSGrant Likely		then the value in "bootm_size" will be used instead.
3243c609719bSwdenk
3244fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_RAMDISK_HIGH:
3245fca43cc8SJohn Rigby		Enable initrd_high functionality.  If defined then the
3246fca43cc8SJohn Rigby		initrd_high feature is enabled and the bootm ramdisk subcommand
3247fca43cc8SJohn Rigby		is enabled.
3248fca43cc8SJohn Rigby
3249fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_GET_CMDLINE:
3250fca43cc8SJohn Rigby		Enables allocating and saving kernel cmdline in space between
3251fca43cc8SJohn Rigby		"bootm_low" and "bootm_low" + BOOTMAPSZ.
3252fca43cc8SJohn Rigby
3253fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_GET_KBD:
3254fca43cc8SJohn Rigby		Enables allocating and saving a kernel copy of the bd_info in
3255fca43cc8SJohn Rigby		space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3256fca43cc8SJohn Rigby
32576d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAX_FLASH_BANKS:
3258c609719bSwdenk		Max number of Flash memory banks
3259c609719bSwdenk
32606d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAX_FLASH_SECT:
3261c609719bSwdenk		Max number of sectors on a Flash chip
3262c609719bSwdenk
32636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_ERASE_TOUT:
3264c609719bSwdenk		Timeout for Flash erase operations (in ms)
3265c609719bSwdenk
32666d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_WRITE_TOUT:
3267c609719bSwdenk		Timeout for Flash write operations (in ms)
3268c609719bSwdenk
32696d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_LOCK_TOUT
32708564acf9Swdenk		Timeout for Flash set sector lock bit operation (in ms)
32718564acf9Swdenk
32726d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_UNLOCK_TOUT
32738564acf9Swdenk		Timeout for Flash clear lock bits operation (in ms)
32748564acf9Swdenk
32756d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_PROTECTION
32768564acf9Swdenk		If defined, hardware flash sectors protection is used
32778564acf9Swdenk		instead of U-Boot software protection.
32788564acf9Swdenk
32796d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_DIRECT_FLASH_TFTP:
3280c609719bSwdenk
3281c609719bSwdenk		Enable TFTP transfers directly to flash memory;
3282c609719bSwdenk		without this option such a download has to be
3283c609719bSwdenk		performed in two steps: (1) download to RAM, and (2)
3284c609719bSwdenk		copy from RAM to flash.
3285c609719bSwdenk
3286c609719bSwdenk		The two-step approach is usually more reliable, since
3287c609719bSwdenk		you can check if the download worked before you erase
328811ccc33fSMarcel Ziswiler		the flash, but in some situations (when system RAM is
328911ccc33fSMarcel Ziswiler		too limited to allow for a temporary copy of the
3290c609719bSwdenk		downloaded image) this option may be very useful.
3291c609719bSwdenk
32926d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_CFI:
3293c609719bSwdenk		Define if the flash driver uses extra elements in the
32945653fc33Swdenk		common flash structure for storing flash geometry.
32955653fc33Swdenk
329600b1883aSJean-Christophe PLAGNIOL-VILLARD- CONFIG_FLASH_CFI_DRIVER
32975653fc33Swdenk		This option also enables the building of the cfi_flash driver
32985653fc33Swdenk		in the drivers directory
329953cf9435Sstroese
330091809ed5SPiotr Ziecik- CONFIG_FLASH_CFI_MTD
330191809ed5SPiotr Ziecik		This option enables the building of the cfi_mtd driver
330291809ed5SPiotr Ziecik		in the drivers directory. The driver exports CFI flash
330391809ed5SPiotr Ziecik		to the MTD layer.
330491809ed5SPiotr Ziecik
33056d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
330696ef831fSGuennadi Liakhovetski		Use buffered writes to flash.
330796ef831fSGuennadi Liakhovetski
330896ef831fSGuennadi Liakhovetski- CONFIG_FLASH_SPANSION_S29WS_N
330996ef831fSGuennadi Liakhovetski		s29ws-n MirrorBit flash has non-standard addresses for buffered
331096ef831fSGuennadi Liakhovetski		write commands.
331196ef831fSGuennadi Liakhovetski
33126d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_QUIET_TEST
33135568e613SStefan Roese		If this option is defined, the common CFI flash doesn't
33145568e613SStefan Roese		print it's warning upon not recognized FLASH banks. This
33155568e613SStefan Roese		is useful, if some of the configured banks are only
33165568e613SStefan Roese		optionally available.
33175568e613SStefan Roese
33189a042e9cSJerry Van Baren- CONFIG_FLASH_SHOW_PROGRESS
33199a042e9cSJerry Van Baren		If defined (must be an integer), print out countdown
33209a042e9cSJerry Van Baren		digits and dots.  Recommended value: 45 (9..1) for 80
33219a042e9cSJerry Van Baren		column displays, 15 (3..1) for 40 column displays.
33229a042e9cSJerry Van Baren
3323352ef3f1SStefan Roese- CONFIG_FLASH_VERIFY
3324352ef3f1SStefan Roese		If defined, the content of the flash (destination) is compared
3325352ef3f1SStefan Roese		against the source after the write operation. An error message
3326352ef3f1SStefan Roese		will be printed when the contents are not identical.
3327352ef3f1SStefan Roese		Please note that this option is useless in nearly all cases,
3328352ef3f1SStefan Roese		since such flash programming errors usually are detected earlier
3329352ef3f1SStefan Roese		while unprotecting/erasing/programming. Please only enable
3330352ef3f1SStefan Roese		this option if you really know what you are doing.
3331352ef3f1SStefan Roese
33326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_RX_ETH_BUFFER:
333311ccc33fSMarcel Ziswiler		Defines the number of Ethernet receive buffers. On some
333411ccc33fSMarcel Ziswiler		Ethernet controllers it is recommended to set this value
333553cf9435Sstroese		to 8 or even higher (EEPRO100 or 405 EMAC), since all
333653cf9435Sstroese		buffers can be full shortly after enabling the interface
333711ccc33fSMarcel Ziswiler		on high Ethernet traffic.
333853cf9435Sstroese		Defaults to 4 if not defined.
3339c609719bSwdenk
3340ea882bafSWolfgang Denk- CONFIG_ENV_MAX_ENTRIES
3341ea882bafSWolfgang Denk
3342ea882bafSWolfgang Denk	Maximum number of entries in the hash table that is used
3343ea882bafSWolfgang Denk	internally to store the environment settings. The default
3344ea882bafSWolfgang Denk	setting is supposed to be generous and should work in most
3345ea882bafSWolfgang Denk	cases. This setting can be used to tune behaviour; see
3346ea882bafSWolfgang Denk	lib/hashtable.c for details.
3347ea882bafSWolfgang Denk
33482598090bSJoe Hershberger- CONFIG_ENV_FLAGS_LIST_DEFAULT
33492598090bSJoe Hershberger- CONFIG_ENV_FLAGS_LIST_STATIC
33501bce2aebSRobert P. J. Day	Enable validation of the values given to environment variables when
33512598090bSJoe Hershberger	calling env set.  Variables can be restricted to only decimal,
33522598090bSJoe Hershberger	hexadecimal, or boolean.  If CONFIG_CMD_NET is also defined,
33532598090bSJoe Hershberger	the variables can also be restricted to IP address or MAC address.
33542598090bSJoe Hershberger
33552598090bSJoe Hershberger	The format of the list is:
33562598090bSJoe Hershberger		type_attribute = [s|d|x|b|i|m]
3357b445bbb4SJeremiah Mahler		access_attribute = [a|r|o|c]
3358b445bbb4SJeremiah Mahler		attributes = type_attribute[access_attribute]
33592598090bSJoe Hershberger		entry = variable_name[:attributes]
33602598090bSJoe Hershberger		list = entry[,list]
33612598090bSJoe Hershberger
33622598090bSJoe Hershberger	The type attributes are:
33632598090bSJoe Hershberger		s - String (default)
33642598090bSJoe Hershberger		d - Decimal
33652598090bSJoe Hershberger		x - Hexadecimal
33662598090bSJoe Hershberger		b - Boolean ([1yYtT|0nNfF])
33672598090bSJoe Hershberger		i - IP address
33682598090bSJoe Hershberger		m - MAC address
33692598090bSJoe Hershberger
3370267541f7SJoe Hershberger	The access attributes are:
3371267541f7SJoe Hershberger		a - Any (default)
3372267541f7SJoe Hershberger		r - Read-only
3373267541f7SJoe Hershberger		o - Write-once
3374267541f7SJoe Hershberger		c - Change-default
3375267541f7SJoe Hershberger
33762598090bSJoe Hershberger	- CONFIG_ENV_FLAGS_LIST_DEFAULT
33772598090bSJoe Hershberger		Define this to a list (string) to define the ".flags"
3378b445bbb4SJeremiah Mahler		environment variable in the default or embedded environment.
33792598090bSJoe Hershberger
33802598090bSJoe Hershberger	- CONFIG_ENV_FLAGS_LIST_STATIC
33812598090bSJoe Hershberger		Define this to a list (string) to define validation that
33822598090bSJoe Hershberger		should be done if an entry is not found in the ".flags"
33832598090bSJoe Hershberger		environment variable.  To override a setting in the static
33842598090bSJoe Hershberger		list, simply add an entry for the same variable name to the
33852598090bSJoe Hershberger		".flags" variable.
33862598090bSJoe Hershberger
3387bdf1fe4eSJoe Hershberger	If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3388bdf1fe4eSJoe Hershberger	regular expression. This allows multiple variables to define the same
3389bdf1fe4eSJoe Hershberger	flags without explicitly listing them for each variable.
3390bdf1fe4eSJoe Hershberger
3391267541f7SJoe Hershberger- CONFIG_ENV_ACCESS_IGNORE_FORCE
3392267541f7SJoe Hershberger	If defined, don't allow the -f switch to env set override variable
3393267541f7SJoe Hershberger	access flags.
3394267541f7SJoe Hershberger
33950d296cc2SGabe Black- CONFIG_USE_STDINT
33960d296cc2SGabe Black	If stdint.h is available with your toolchain you can define this
33970d296cc2SGabe Black	option to enable it. You can provide option 'USE_STDINT=1' when
33980d296cc2SGabe Black	building U-Boot to enable this.
33990d296cc2SGabe Black
3400c609719bSwdenkThe following definitions that deal with the placement and management
3401c609719bSwdenkof environment data (variable area); in general, we support the
3402c609719bSwdenkfollowing configurations:
3403c609719bSwdenk
3404c3eb3fe4SMike Frysinger- CONFIG_BUILD_ENVCRC:
3405c3eb3fe4SMike Frysinger
3406c3eb3fe4SMike Frysinger	Builds up envcrc with the target environment so that external utils
3407c3eb3fe4SMike Frysinger	may easily extract it and embed it in final U-Boot images.
3408c3eb3fe4SMike Frysinger
3409c609719bSwdenkBE CAREFUL! The first access to the environment happens quite early
3410b445bbb4SJeremiah Mahlerin U-Boot initialization (when we try to get the setting of for the
341111ccc33fSMarcel Ziswilerconsole baudrate). You *MUST* have mapped your NVRAM area then, or
3412c609719bSwdenkU-Boot will hang.
3413c609719bSwdenk
3414c609719bSwdenkPlease note that even with NVRAM we still use a copy of the
3415c609719bSwdenkenvironment in RAM: we could work on NVRAM directly, but we want to
3416c609719bSwdenkkeep settings there always unmodified except somebody uses "saveenv"
3417c609719bSwdenkto save the current settings.
3418c609719bSwdenk
34190a85a9e7SLiu GangBE CAREFUL! For some special cases, the local device can not use
34200a85a9e7SLiu Gang"saveenv" command. For example, the local device will get the
3421fc54c7faSLiu Gangenvironment stored in a remote NOR flash by SRIO or PCIE link,
3422fc54c7faSLiu Gangbut it can not erase, write this NOR flash by SRIO or PCIE interface.
34230a85a9e7SLiu Gang
3424b74ab737SGuennadi Liakhovetski- CONFIG_NAND_ENV_DST
3425b74ab737SGuennadi Liakhovetski
3426b74ab737SGuennadi Liakhovetski	Defines address in RAM to which the nand_spl code should copy the
3427b74ab737SGuennadi Liakhovetski	environment. If redundant environment is used, it will be copied to
3428b74ab737SGuennadi Liakhovetski	CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3429b74ab737SGuennadi Liakhovetski
3430e881cb56SBruce AdlerPlease note that the environment is read-only until the monitor
3431c609719bSwdenkhas been relocated to RAM and a RAM copy of the environment has been
3432cdb74977SWolfgang Denkcreated; also, when using EEPROM you will have to use getenv_f()
3433c609719bSwdenkuntil then to read environment variables.
3434c609719bSwdenk
343585ec0bccSwdenkThe environment is protected by a CRC32 checksum. Before the monitor
343685ec0bccSwdenkis relocated into RAM, as a result of a bad CRC you will be working
343785ec0bccSwdenkwith the compiled-in default environment - *silently*!!! [This is
343885ec0bccSwdenknecessary, because the first environment variable we need is the
343985ec0bccSwdenk"baudrate" setting for the console - if we have a bad CRC, we don't
344085ec0bccSwdenkhave any device yet where we could complain.]
3441c609719bSwdenk
3442c609719bSwdenkNote: once the monitor has been relocated, then it will complain if
3443c609719bSwdenkthe default environment is used; a new CRC is computed as soon as you
344485ec0bccSwdenkuse the "saveenv" command to store a valid environment.
3445c609719bSwdenk
34466d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3447fc3e2165Swdenk		Echo the inverted Ethernet link state to the fault LED.
3448fc3e2165Swdenk
34496d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3450fc3e2165Swdenk		      also needs to be defined.
3451fc3e2165Swdenk
34526d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FAULT_MII_ADDR:
3453fc3e2165Swdenk		MII address of the PHY to check for the Ethernet link state.
3454c609719bSwdenk
3455f5675aa5SRon Madrid- CONFIG_NS16550_MIN_FUNCTIONS:
3456f5675aa5SRon Madrid		Define this if you desire to only have use of the NS16550_init
3457f5675aa5SRon Madrid		and NS16550_putc functions for the serial driver located at
3458f5675aa5SRon Madrid		drivers/serial/ns16550.c.  This option is useful for saving
3459f5675aa5SRon Madrid		space for already greatly restricted images, including but not
3460f5675aa5SRon Madrid		limited to NAND_SPL configurations.
3461f5675aa5SRon Madrid
3462b2b92f53SSimon Glass- CONFIG_DISPLAY_BOARDINFO
3463b2b92f53SSimon Glass		Display information about the board that U-Boot is running on
3464b2b92f53SSimon Glass		when U-Boot starts up. The board function checkboard() is called
3465b2b92f53SSimon Glass		to do this.
3466b2b92f53SSimon Glass
3467e2e3e2b1SSimon Glass- CONFIG_DISPLAY_BOARDINFO_LATE
3468e2e3e2b1SSimon Glass		Similar to the previous option, but display this information
3469e2e3e2b1SSimon Glass		later, once stdio is running and output goes to the LCD, if
3470e2e3e2b1SSimon Glass		present.
3471e2e3e2b1SSimon Glass
3472feb85801SSascha Silbe- CONFIG_BOARD_SIZE_LIMIT:
3473feb85801SSascha Silbe		Maximum size of the U-Boot image. When defined, the
3474feb85801SSascha Silbe		build system checks that the actual size does not
3475feb85801SSascha Silbe		exceed it.
3476feb85801SSascha Silbe
3477c609719bSwdenkLow Level (hardware related) configuration options:
3478dc7c9a1aSwdenk---------------------------------------------------
3479c609719bSwdenk
34806d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CACHELINE_SIZE:
3481c609719bSwdenk		Cache Line Size of the CPU.
3482c609719bSwdenk
3483e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_DEFAULT:
3484e46fedfeSTimur Tabi		Default (power-on reset) physical address of CCSR on Freescale
3485e46fedfeSTimur Tabi		PowerPC SOCs.
3486e46fedfeSTimur Tabi
3487e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR:
3488e46fedfeSTimur Tabi		Virtual address of CCSR.  On a 32-bit build, this is typically
3489e46fedfeSTimur Tabi		the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3490e46fedfeSTimur Tabi
3491e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS:
3492e46fedfeSTimur Tabi		Physical address of CCSR.  CCSR can be relocated to a new
3493e46fedfeSTimur Tabi		physical address, if desired.  In this case, this macro should
3494e46fedfeSTimur Tabi		be set to that address.	 Otherwise, it should be set to the
3495e46fedfeSTimur Tabi		same value as CONFIG_SYS_CCSRBAR_DEFAULT.  For example, CCSR
3496e46fedfeSTimur Tabi		is typically relocated on 36-bit builds.  It is recommended
3497e46fedfeSTimur Tabi		that this macro be defined via the _HIGH and _LOW macros:
3498e46fedfeSTimur Tabi
3499e46fedfeSTimur Tabi		#define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3500e46fedfeSTimur Tabi			* 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3501e46fedfeSTimur Tabi
3502e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3503e46fedfeSTimur Tabi		Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS.	This value is typically
3504e46fedfeSTimur Tabi		either 0 (32-bit build) or 0xF (36-bit build).	This macro is
3505e46fedfeSTimur Tabi		used in assembly code, so it must not contain typecasts or
3506e46fedfeSTimur Tabi		integer size suffixes (e.g. "ULL").
3507e46fedfeSTimur Tabi
3508e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3509e46fedfeSTimur Tabi		Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS.  This macro is
3510e46fedfeSTimur Tabi		used in assembly code, so it must not contain typecasts or
3511e46fedfeSTimur Tabi		integer size suffixes (e.g. "ULL").
3512e46fedfeSTimur Tabi
3513e46fedfeSTimur Tabi- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3514e46fedfeSTimur Tabi		If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3515e46fedfeSTimur Tabi		forced to a value that ensures that CCSR is not relocated.
3516e46fedfeSTimur Tabi
35177f6c2cbcSwdenk- Floppy Disk Support:
35186d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FDC_DRIVE_NUMBER
35197f6c2cbcSwdenk
35207f6c2cbcSwdenk		the default drive number (default value 0)
35217f6c2cbcSwdenk
35226d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_ISA_IO_STRIDE
35237f6c2cbcSwdenk
352411ccc33fSMarcel Ziswiler		defines the spacing between FDC chipset registers
35257f6c2cbcSwdenk		(default value 1)
35267f6c2cbcSwdenk
35276d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_ISA_IO_OFFSET
35287f6c2cbcSwdenk
35297f6c2cbcSwdenk		defines the offset of register from address. It
35307f6c2cbcSwdenk		depends on which part of the data bus is connected to
353111ccc33fSMarcel Ziswiler		the FDC chipset. (default value 0)
35327f6c2cbcSwdenk
35336d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
35346d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
35357f6c2cbcSwdenk		default value.
35367f6c2cbcSwdenk
35376d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		if CONFIG_SYS_FDC_HW_INIT is defined, then the function
35387f6c2cbcSwdenk		fdc_hw_init() is called at the beginning of the FDC
35397f6c2cbcSwdenk		setup. fdc_hw_init() must be provided by the board
3540b445bbb4SJeremiah Mahler		source code. It is used to make hardware-dependent
35417f6c2cbcSwdenk		initializations.
35427f6c2cbcSwdenk
35430abddf82SMacpaul Lin- CONFIG_IDE_AHB:
35440abddf82SMacpaul Lin		Most IDE controllers were designed to be connected with PCI
35450abddf82SMacpaul Lin		interface. Only few of them were designed for AHB interface.
35460abddf82SMacpaul Lin		When software is doing ATA command and data transfer to
35470abddf82SMacpaul Lin		IDE devices through IDE-AHB controller, some additional
35480abddf82SMacpaul Lin		registers accessing to these kind of IDE-AHB controller
3549b445bbb4SJeremiah Mahler		is required.
35500abddf82SMacpaul Lin
35516d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_IMMR:	Physical address of the Internal Memory.
355225d6712aSwdenk		DO NOT CHANGE unless you know exactly what you're
3553907208c4SChristophe Leroy		doing! (11-4) [MPC8xx systems only]
3554c609719bSwdenk
35556d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_INIT_RAM_ADDR:
3556c609719bSwdenk
35577152b1d0Swdenk		Start address of memory area that can be used for
3558c609719bSwdenk		initial data and stack; please note that this must be
3559c609719bSwdenk		writable memory that is working WITHOUT special
3560c609719bSwdenk		initialization, i. e. you CANNOT use normal RAM which
3561c609719bSwdenk		will become available only after programming the
3562c609719bSwdenk		memory controller and running certain initialization
3563c609719bSwdenk		sequences.
3564c609719bSwdenk
3565c609719bSwdenk		U-Boot uses the following memory types:
3566907208c4SChristophe Leroy		- MPC8xx: IMMR (internal memory of the CPU)
3567c609719bSwdenk
35686d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_GBL_DATA_OFFSET:
3569c609719bSwdenk
3570c609719bSwdenk		Offset of the initial data structure in the memory
35716d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
35726d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3573c609719bSwdenk		data is located at the end of the available space
3574553f0982SWolfgang Denk		(sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3575acd51f9dSSimon Glass		GENERATED_GBL_DATA_SIZE), and the initial stack is just
35766d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
35776d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_GBL_DATA_OFFSET) downward.
3578c609719bSwdenk
3579c609719bSwdenk	Note:
3580c609719bSwdenk		On the MPC824X (or other systems that use the data
3581c609719bSwdenk		cache for initial memory) the address chosen for
35826d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3583c609719bSwdenk		point to an otherwise UNUSED address space between
3584c609719bSwdenk		the top of RAM and the start of the PCI space.
3585c609719bSwdenk
35866d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SCCR:	System Clock and reset Control Register (15-27)
3587c609719bSwdenk
35886d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_OR_TIMING_SDRAM:
3589c609719bSwdenk		SDRAM timing
3590c609719bSwdenk
35916d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAMR_PTA:
3592c609719bSwdenk		periodic timer for refresh
3593c609719bSwdenk
35946d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
35956d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
35966d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
35976d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_BR1_PRELIM:
3598c609719bSwdenk		Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3599c609719bSwdenk
3600c609719bSwdenk- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
36016d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
36026d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3603c609719bSwdenk		Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3604c609719bSwdenk
360569fd2d3bSAndrew Sharp- CONFIG_PCI_ENUM_ONLY
3606b445bbb4SJeremiah Mahler		Only scan through and get the devices on the buses.
360769fd2d3bSAndrew Sharp		Don't do any setup work, presumably because someone or
360869fd2d3bSAndrew Sharp		something has already done it, and we don't need to do it
360969fd2d3bSAndrew Sharp		a second time.	Useful for platforms that are pre-booted
361069fd2d3bSAndrew Sharp		by coreboot or similar.
361169fd2d3bSAndrew Sharp
3612842033e6SGabor Juhos- CONFIG_PCI_INDIRECT_BRIDGE:
3613842033e6SGabor Juhos		Enable support for indirect PCI bridges.
3614842033e6SGabor Juhos
3615a09b9b68SKumar Gala- CONFIG_SYS_SRIO:
3616a09b9b68SKumar Gala		Chip has SRIO or not
3617a09b9b68SKumar Gala
3618a09b9b68SKumar Gala- CONFIG_SRIO1:
3619a09b9b68SKumar Gala		Board has SRIO 1 port available
3620a09b9b68SKumar Gala
3621a09b9b68SKumar Gala- CONFIG_SRIO2:
3622a09b9b68SKumar Gala		Board has SRIO 2 port available
3623a09b9b68SKumar Gala
3624c8b28152SLiu Gang- CONFIG_SRIO_PCIE_BOOT_MASTER
3625c8b28152SLiu Gang		Board can support master function for Boot from SRIO and PCIE
3626c8b28152SLiu Gang
3627a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_VIRT:
3628a09b9b68SKumar Gala		Virtual Address of SRIO port 'n' memory region
3629a09b9b68SKumar Gala
3630a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_PHYS:
3631a09b9b68SKumar Gala		Physical Address of SRIO port 'n' memory region
3632a09b9b68SKumar Gala
3633a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_SIZE:
3634a09b9b68SKumar Gala		Size of SRIO port 'n' memory region
3635a09b9b68SKumar Gala
363666bd1846SFabio Estevam- CONFIG_SYS_NAND_BUSWIDTH_16BIT
363766bd1846SFabio Estevam		Defined to tell the NAND controller that the NAND chip is using
363866bd1846SFabio Estevam		a 16 bit bus.
363966bd1846SFabio Estevam		Not all NAND drivers use this symbol.
3640a430e916SFabio Estevam		Example of drivers that use it:
364166bd1846SFabio Estevam		- drivers/mtd/nand/ndfc.c
3642a430e916SFabio Estevam		- drivers/mtd/nand/mxc_nand.c
3643eced4626SAlex Waterman
3644eced4626SAlex Waterman- CONFIG_SYS_NDFC_EBC0_CFG
3645eced4626SAlex Waterman		Sets the EBC0_CFG register for the NDFC. If not defined
3646eced4626SAlex Waterman		a default value will be used.
3647eced4626SAlex Waterman
3648bb99ad6dSBen Warren- CONFIG_SPD_EEPROM
3649218ca724SWolfgang Denk		Get DDR timing information from an I2C EEPROM. Common
3650218ca724SWolfgang Denk		with pluggable memory modules such as SODIMMs
3651218ca724SWolfgang Denk
3652bb99ad6dSBen Warren  SPD_EEPROM_ADDRESS
3653bb99ad6dSBen Warren		I2C address of the SPD EEPROM
3654bb99ad6dSBen Warren
36556d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SPD_BUS_NUM
3656218ca724SWolfgang Denk		If SPD EEPROM is on an I2C bus other than the first
3657218ca724SWolfgang Denk		one, specify here. Note that the value must resolve
3658218ca724SWolfgang Denk		to something your driver can deal with.
3659bb99ad6dSBen Warren
36601b3e3c4fSYork Sun- CONFIG_SYS_DDR_RAW_TIMING
36611b3e3c4fSYork Sun		Get DDR timing information from other than SPD. Common with
36621b3e3c4fSYork Sun		soldered DDR chips onboard without SPD. DDR raw timing
36631b3e3c4fSYork Sun		parameters are extracted from datasheet and hard-coded into
36641b3e3c4fSYork Sun		header files or board specific files.
36651b3e3c4fSYork Sun
36666f5e1dc5SYork Sun- CONFIG_FSL_DDR_INTERACTIVE
36676f5e1dc5SYork Sun		Enable interactive DDR debugging. See doc/README.fsl-ddr.
36686f5e1dc5SYork Sun
3669e32d59a2SYork Sun- CONFIG_FSL_DDR_SYNC_REFRESH
3670e32d59a2SYork Sun		Enable sync of refresh for multiple controllers.
3671e32d59a2SYork Sun
36724516ff81SYork Sun- CONFIG_FSL_DDR_BIST
36734516ff81SYork Sun		Enable built-in memory test for Freescale DDR controllers.
36744516ff81SYork Sun
36756d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_83XX_DDR_USES_CS0
3676218ca724SWolfgang Denk		Only for 83xx systems. If specified, then DDR should
3677218ca724SWolfgang Denk		be configured using CS0 and CS1 instead of CS2 and CS3.
36782ad6b513STimur Tabi
3679c26e454dSwdenk- CONFIG_RMII
3680c26e454dSwdenk		Enable RMII mode for all FECs.
3681c26e454dSwdenk		Note that this is a global option, we can't
3682c26e454dSwdenk		have one FEC in standard MII mode and another in RMII mode.
3683c26e454dSwdenk
36845cf91d6bSwdenk- CONFIG_CRC32_VERIFY
36855cf91d6bSwdenk		Add a verify option to the crc32 command.
36865cf91d6bSwdenk		The syntax is:
36875cf91d6bSwdenk
36885cf91d6bSwdenk		=> crc32 -v <address> <count> <crc32>
36895cf91d6bSwdenk
36905cf91d6bSwdenk		Where address/count indicate a memory area
36915cf91d6bSwdenk		and crc32 is the correct crc32 which the
36925cf91d6bSwdenk		area should have.
36935cf91d6bSwdenk
369456523f12Swdenk- CONFIG_LOOPW
369556523f12Swdenk		Add the "loopw" memory command. This only takes effect if
3696*493f420eSSimon Glass		the memory commands are activated globally (CONFIG_CMD_MEMORY).
369756523f12Swdenk
36987b466641Sstroese- CONFIG_MX_CYCLIC
36997b466641Sstroese		Add the "mdc" and "mwc" memory commands. These are cyclic
37007b466641Sstroese		"md/mw" commands.
37017b466641Sstroese		Examples:
37027b466641Sstroese
37037b466641Sstroese		=> mdc.b 10 4 500
37047b466641Sstroese		This command will print 4 bytes (10,11,12,13) each 500 ms.
37057b466641Sstroese
37067b466641Sstroese		=> mwc.l 100 12345678 10
37077b466641Sstroese		This command will write 12345678 to address 100 all 10 ms.
37087b466641Sstroese
37097b466641Sstroese		This only takes effect if the memory commands are activated
3710*493f420eSSimon Glass		globally (CONFIG_CMD_MEMORY).
37117b466641Sstroese
37128aa1a2d1Swdenk- CONFIG_SKIP_LOWLEVEL_INIT
3713afc1ce82SMacpaul Lin		[ARM, NDS32, MIPS only] If this variable is defined, then certain
3714e03f3169SWolfgang Denk		low level initializations (like setting up the memory
3715e03f3169SWolfgang Denk		controller) are omitted and/or U-Boot does not
3716e03f3169SWolfgang Denk		relocate itself into RAM.
37178aa1a2d1Swdenk
3718e03f3169SWolfgang Denk		Normally this variable MUST NOT be defined. The only
3719e03f3169SWolfgang Denk		exception is when U-Boot is loaded (to RAM) by some
3720e03f3169SWolfgang Denk		other boot loader or by a debugger which performs
3721e03f3169SWolfgang Denk		these initializations itself.
37228aa1a2d1Swdenk
3723b5bd0982SSimon Glass- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3724b5bd0982SSimon Glass		[ARM926EJ-S only] This allows just the call to lowlevel_init()
372590211f77Syeongjun Kim		to be skipped. The normal CP15 init (such as enabling the
3726b5bd0982SSimon Glass		instruction cache) is still performed.
3727b5bd0982SSimon Glass
3728401bb30bSAneesh V- CONFIG_SPL_BUILD
3729df81238bSMagnus Lilja		Modifies the behaviour of start.S when compiling a loader
3730df81238bSMagnus Lilja		that is executed before the actual U-Boot. E.g. when
3731df81238bSMagnus Lilja		compiling a NAND SPL.
3732400558b5Swdenk
37333aa29de0SYing Zhang- CONFIG_TPL_BUILD
37343aa29de0SYing Zhang		Modifies the behaviour of start.S  when compiling a loader
37353aa29de0SYing Zhang		that is executed after the SPL and before the actual U-Boot.
37363aa29de0SYing Zhang		It is loaded by the SPL.
37373aa29de0SYing Zhang
37385df572f0SYing Zhang- CONFIG_SYS_MPC85XX_NO_RESETVEC
37395df572f0SYing Zhang		Only for 85xx systems. If this variable is specified, the section
37405df572f0SYing Zhang		.resetvec is not kept and the section .bootpg is placed in the
37415df572f0SYing Zhang		previous 4k of the .text section.
37425df572f0SYing Zhang
37434213fc29SSimon Glass- CONFIG_ARCH_MAP_SYSMEM
37444213fc29SSimon Glass		Generally U-Boot (and in particular the md command) uses
37454213fc29SSimon Glass		effective address. It is therefore not necessary to regard
37464213fc29SSimon Glass		U-Boot address as virtual addresses that need to be translated
37474213fc29SSimon Glass		to physical addresses. However, sandbox requires this, since
37484213fc29SSimon Glass		it maintains its own little RAM buffer which contains all
37494213fc29SSimon Glass		addressable memory. This option causes some memory accesses
37504213fc29SSimon Glass		to be mapped through map_sysmem() / unmap_sysmem().
37514213fc29SSimon Glass
3752588a13f7SSimon Glass- CONFIG_X86_RESET_VECTOR
3753588a13f7SSimon Glass		If defined, the x86 reset vector code is included. This is not
3754588a13f7SSimon Glass		needed when U-Boot is running from Coreboot.
3755b16f521aSGabe Black
375616678eb4SHeiko Schocher- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
375716678eb4SHeiko Schocher		Enables the RTC32K OSC on AM33xx based plattforms
375816678eb4SHeiko Schocher
3759999d7d32SKaricheri, Muralidharan- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3760999d7d32SKaricheri, Muralidharan		Option to disable subpage write in NAND driver
3761999d7d32SKaricheri, Muralidharan		driver that uses this:
3762999d7d32SKaricheri, Muralidharan		drivers/mtd/nand/davinci_nand.c
3763999d7d32SKaricheri, Muralidharan
3764f2717b47STimur TabiFreescale QE/FMAN Firmware Support:
3765f2717b47STimur Tabi-----------------------------------
3766f2717b47STimur Tabi
3767f2717b47STimur TabiThe Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3768f2717b47STimur Tabiloading of "firmware", which is encoded in the QE firmware binary format.
3769f2717b47STimur TabiThis firmware often needs to be loaded during U-Boot booting, so macros
3770f2717b47STimur Tabiare used to identify the storage device (NOR flash, SPI, etc) and the address
3771f2717b47STimur Tabiwithin that device.
3772f2717b47STimur Tabi
3773dcf1d774SZhao Qiang- CONFIG_SYS_FMAN_FW_ADDR
3774dcf1d774SZhao Qiang	The address in the storage device where the FMAN microcode is located.  The
3775dcf1d774SZhao Qiang	meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3776dcf1d774SZhao Qiang	is also specified.
3777dcf1d774SZhao Qiang
3778dcf1d774SZhao Qiang- CONFIG_SYS_QE_FW_ADDR
3779dcf1d774SZhao Qiang	The address in the storage device where the QE microcode is located.  The
3780f2717b47STimur Tabi	meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3781f2717b47STimur Tabi	is also specified.
3782f2717b47STimur Tabi
3783f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_LENGTH
3784f2717b47STimur Tabi	The maximum possible size of the firmware.  The firmware binary format
3785f2717b47STimur Tabi	has a field that specifies the actual size of the firmware, but it
3786f2717b47STimur Tabi	might not be possible to read any part of the firmware unless some
3787f2717b47STimur Tabi	local storage is allocated to hold the entire firmware first.
3788f2717b47STimur Tabi
3789f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3790f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3791f2717b47STimur Tabi	normal addressable memory via the LBC.  CONFIG_SYS_FMAN_FW_ADDR is the
3792f2717b47STimur Tabi	virtual address in NOR flash.
3793f2717b47STimur Tabi
3794f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3795f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located in NAND flash.
3796f2717b47STimur Tabi	CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3797f2717b47STimur Tabi
3798f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3799f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located on the primary SD/MMC
3800f2717b47STimur Tabi	device.  CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3801f2717b47STimur Tabi
3802292dc6c5SLiu Gang- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3803292dc6c5SLiu Gang	Specifies that QE/FMAN firmware is located in the remote (master)
3804292dc6c5SLiu Gang	memory space.	CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
3805fc54c7faSLiu Gang	can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3806fc54c7faSLiu Gang	window->master inbound window->master LAW->the ucode address in
3807fc54c7faSLiu Gang	master's memory space.
3808f2717b47STimur Tabi
3809b940ca64SJ. German RiveraFreescale Layerscape Management Complex Firmware Support:
3810b940ca64SJ. German Rivera---------------------------------------------------------
3811b940ca64SJ. German RiveraThe Freescale Layerscape Management Complex (MC) supports the loading of
3812b940ca64SJ. German Rivera"firmware".
3813b940ca64SJ. German RiveraThis firmware often needs to be loaded during U-Boot booting, so macros
3814b940ca64SJ. German Riveraare used to identify the storage device (NOR flash, SPI, etc) and the address
3815b940ca64SJ. German Riverawithin that device.
3816b940ca64SJ. German Rivera
3817b940ca64SJ. German Rivera- CONFIG_FSL_MC_ENET
3818b940ca64SJ. German Rivera	Enable the MC driver for Layerscape SoCs.
3819b940ca64SJ. German Rivera
38205c055089SPrabhakar KushwahaFreescale Layerscape Debug Server Support:
38215c055089SPrabhakar Kushwaha-------------------------------------------
38225c055089SPrabhakar KushwahaThe Freescale Layerscape Debug Server Support supports the loading of
38235c055089SPrabhakar Kushwaha"Debug Server firmware" and triggering SP boot-rom.
38245c055089SPrabhakar KushwahaThis firmware often needs to be loaded during U-Boot booting.
38255c055089SPrabhakar Kushwaha
3826c0492141SYork Sun- CONFIG_SYS_MC_RSV_MEM_ALIGN
3827c0492141SYork Sun	Define alignment of reserved memory MC requires
38285c055089SPrabhakar Kushwaha
3829f3f431a7SPaul KocialkowskiReproducible builds
3830f3f431a7SPaul Kocialkowski-------------------
3831f3f431a7SPaul Kocialkowski
3832f3f431a7SPaul KocialkowskiIn order to achieve reproducible builds, timestamps used in the U-Boot build
3833f3f431a7SPaul Kocialkowskiprocess have to be set to a fixed value.
3834f3f431a7SPaul Kocialkowski
3835f3f431a7SPaul KocialkowskiThis is done using the SOURCE_DATE_EPOCH environment variable.
3836f3f431a7SPaul KocialkowskiSOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3837f3f431a7SPaul Kocialkowskioption for U-Boot or an environment variable in U-Boot.
3838f3f431a7SPaul Kocialkowski
3839f3f431a7SPaul KocialkowskiSOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3840f3f431a7SPaul Kocialkowski
3841c609719bSwdenkBuilding the Software:
3842c609719bSwdenk======================
3843c609719bSwdenk
3844218ca724SWolfgang DenkBuilding U-Boot has been tested in several native build environments
3845218ca724SWolfgang Denkand in many different cross environments. Of course we cannot support
3846218ca724SWolfgang Denkall possibly existing versions of cross development tools in all
3847218ca724SWolfgang Denk(potentially obsolete) versions. In case of tool chain problems we
3848218ca724SWolfgang Denkrecommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3849218ca724SWolfgang Denkwhich is extensively used to build and test U-Boot.
3850c609719bSwdenk
3851218ca724SWolfgang DenkIf you are not using a native environment, it is assumed that you
3852218ca724SWolfgang Denkhave GNU cross compiling tools available in your path. In this case,
3853218ca724SWolfgang Denkyou must set the environment variable CROSS_COMPILE in your shell.
3854218ca724SWolfgang DenkNote that no changes to the Makefile or any other source files are
3855218ca724SWolfgang Denknecessary. For example using the ELDK on a 4xx CPU, please enter:
3856c609719bSwdenk
3857218ca724SWolfgang Denk	$ CROSS_COMPILE=ppc_4xx-
3858218ca724SWolfgang Denk	$ export CROSS_COMPILE
3859c609719bSwdenk
38602f8d396bSPeter TyserNote: If you wish to generate Windows versions of the utilities in
38612f8d396bSPeter Tyser      the tools directory you can use the MinGW toolchain
38622f8d396bSPeter Tyser      (http://www.mingw.org).  Set your HOST tools to the MinGW
38632f8d396bSPeter Tyser      toolchain and execute 'make tools'.  For example:
38642f8d396bSPeter Tyser
38652f8d396bSPeter Tyser       $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
38662f8d396bSPeter Tyser
38672f8d396bSPeter Tyser      Binaries such as tools/mkimage.exe will be created which can
38682f8d396bSPeter Tyser      be executed on computers running Windows.
38692f8d396bSPeter Tyser
3870c609719bSwdenkU-Boot is intended to be simple to build. After installing the
3871c609719bSwdenksources you must configure U-Boot for one specific board type. This
3872c609719bSwdenkis done by typing:
3873c609719bSwdenk
3874ab584d67SHolger Freyther	make NAME_defconfig
3875c609719bSwdenk
3876ab584d67SHolger Freytherwhere "NAME_defconfig" is the name of one of the existing configu-
38774d675ae6SMichael Jonesrations; see boards.cfg for supported names.
387854387ac9Swdenk
3879c609719bSwdenkNote: for some board special configuration names may exist; check if
3880c609719bSwdenk      additional information is available from the board vendor; for
38812729af9dSwdenk      instance, the TQM823L systems are available without (standard)
38822729af9dSwdenk      or with LCD support. You can select such additional "features"
388311ccc33fSMarcel Ziswiler      when choosing the configuration, i. e.
3884c609719bSwdenk
3885ab584d67SHolger Freyther      make TQM823L_defconfig
38862729af9dSwdenk	- will configure for a plain TQM823L, i. e. no LCD support
3887c609719bSwdenk
3888ab584d67SHolger Freyther      make TQM823L_LCD_defconfig
3889c609719bSwdenk	- will configure for a TQM823L with U-Boot console on LCD
3890c609719bSwdenk
3891c609719bSwdenk      etc.
3892c609719bSwdenk
3893c609719bSwdenk
3894c609719bSwdenkFinally, type "make all", and you should get some working U-Boot
38957152b1d0Swdenkimages ready for download to / installation on your system:
3896c609719bSwdenk
3897c609719bSwdenk- "u-boot.bin" is a raw binary image
3898c609719bSwdenk- "u-boot" is an image in ELF binary format
3899c609719bSwdenk- "u-boot.srec" is in Motorola S-Record format
3900c609719bSwdenk
3901baf31249SMarian BalakowiczBy default the build is performed locally and the objects are saved
3902baf31249SMarian Balakowiczin the source directory. One of the two methods can be used to change
3903baf31249SMarian Balakowiczthis behavior and build U-Boot to some external directory:
3904baf31249SMarian Balakowicz
3905baf31249SMarian Balakowicz1. Add O= to the make command line invocations:
3906baf31249SMarian Balakowicz
3907baf31249SMarian Balakowicz	make O=/tmp/build distclean
3908ab584d67SHolger Freyther	make O=/tmp/build NAME_defconfig
3909baf31249SMarian Balakowicz	make O=/tmp/build all
3910baf31249SMarian Balakowicz
3911adbba996STimo Ketola2. Set environment variable KBUILD_OUTPUT to point to the desired location:
3912baf31249SMarian Balakowicz
3913adbba996STimo Ketola	export KBUILD_OUTPUT=/tmp/build
3914baf31249SMarian Balakowicz	make distclean
3915ab584d67SHolger Freyther	make NAME_defconfig
3916baf31249SMarian Balakowicz	make all
3917baf31249SMarian Balakowicz
3918adbba996STimo KetolaNote that the command line "O=" setting overrides the KBUILD_OUTPUT environment
3919baf31249SMarian Balakowiczvariable.
3920baf31249SMarian Balakowicz
3921c609719bSwdenk
3922c609719bSwdenkPlease be aware that the Makefiles assume you are using GNU make, so
3923c609719bSwdenkfor instance on NetBSD you might need to use "gmake" instead of
3924c609719bSwdenknative "make".
3925c609719bSwdenk
3926c609719bSwdenk
3927c609719bSwdenkIf the system board that you have is not listed, then you will need
3928c609719bSwdenkto port U-Boot to your hardware platform. To do this, follow these
3929c609719bSwdenksteps:
3930c609719bSwdenk
39313c1496cdSPhil Sutter1.  Create a new directory to hold your board specific code. Add any
393285ec0bccSwdenk    files you need. In your board directory, you will need at least
39333c1496cdSPhil Sutter    the "Makefile" and a "<board>.c".
39343c1496cdSPhil Sutter2.  Create a new configuration file "include/configs/<board>.h" for
39353c1496cdSPhil Sutter    your board.
3936c609719bSwdenk3.  If you're porting U-Boot to a new CPU, then also create a new
3937c609719bSwdenk    directory to hold your CPU specific code. Add any files you need.
3938ab584d67SHolger Freyther4.  Run "make <board>_defconfig" with your new name.
3939c609719bSwdenk5.  Type "make", and you should get a working "u-boot.srec" file
3940c609719bSwdenk    to be installed on your target system.
394185ec0bccSwdenk6.  Debug and solve any problems that might arise.
3942c609719bSwdenk    [Of course, this last step is much harder than it sounds.]
3943c609719bSwdenk
3944c609719bSwdenk
3945c609719bSwdenkTesting of U-Boot Modifications, Ports to New Hardware, etc.:
3946c609719bSwdenk==============================================================
3947c609719bSwdenk
3948c609719bSwdenkIf you have modified U-Boot sources (for instance added a new board
3949c609719bSwdenkor support for new devices, a new CPU, etc.) you are expected to
3950c609719bSwdenkprovide feedback to the other developers. The feedback normally takes
3951c609719bSwdenkthe form of a "patch", i. e. a context diff against a certain (latest
3952218ca724SWolfgang Denkofficial or latest in the git repository) version of U-Boot sources.
3953c609719bSwdenk
3954c609719bSwdenkBut before you submit such a patch, please verify that your modifi-
3955c609719bSwdenkcation did not break existing code. At least make sure that *ALL* of
3956c609719bSwdenkthe supported boards compile WITHOUT ANY compiler warnings. To do so,
39576de80f21SSimon Glassjust run the buildman script (tools/buildman/buildman), which will
39586de80f21SSimon Glassconfigure and build U-Boot for ALL supported system. Be warned, this
39596de80f21SSimon Glasswill take a while. Please see the buildman README, or run 'buildman -H'
39606de80f21SSimon Glassfor documentation.
3961baf31249SMarian Balakowicz
3962baf31249SMarian Balakowicz
3963c609719bSwdenkSee also "U-Boot Porting Guide" below.
3964c609719bSwdenk
3965c609719bSwdenk
3966c609719bSwdenkMonitor Commands - Overview:
3967c609719bSwdenk============================
3968c609719bSwdenk
3969c609719bSwdenkgo	- start application at address 'addr'
3970c609719bSwdenkrun	- run commands in an environment variable
3971c609719bSwdenkbootm	- boot application image from memory
3972c609719bSwdenkbootp	- boot image via network using BootP/TFTP protocol
397344f074c7SMarek Vasutbootz   - boot zImage from memory
3974c609719bSwdenktftpboot- boot image via network using TFTP protocol
3975c609719bSwdenk	       and env variables "ipaddr" and "serverip"
3976c609719bSwdenk	       (and eventually "gatewayip")
39771fb7cd49SSimon Glasstftpput - upload a file via network using TFTP protocol
3978c609719bSwdenkrarpboot- boot image via network using RARP/TFTP protocol
3979c609719bSwdenkdiskboot- boot from IDE devicebootd   - boot default, i.e., run 'bootcmd'
3980c609719bSwdenkloads	- load S-Record file over serial line
3981c609719bSwdenkloadb	- load binary file over serial line (kermit mode)
3982c609719bSwdenkmd	- memory display
3983c609719bSwdenkmm	- memory modify (auto-incrementing)
3984c609719bSwdenknm	- memory modify (constant address)
3985c609719bSwdenkmw	- memory write (fill)
3986c609719bSwdenkcp	- memory copy
3987c609719bSwdenkcmp	- memory compare
3988c609719bSwdenkcrc32	- checksum calculation
39890f89c54bSPeter Tyseri2c	- I2C sub-system
3990c609719bSwdenksspi	- SPI utility commands
3991c609719bSwdenkbase	- print or set address offset
3992c609719bSwdenkprintenv- print environment variables
3993c609719bSwdenksetenv	- set environment variables
3994c609719bSwdenksaveenv - save environment variables to persistent storage
3995c609719bSwdenkprotect - enable or disable FLASH write protection
3996c609719bSwdenkerase	- erase FLASH memory
3997c609719bSwdenkflinfo	- print FLASH memory information
399810635afaSKarl O. Pincnand	- NAND memory operations (see doc/README.nand)
3999c609719bSwdenkbdinfo	- print Board Info structure
4000c609719bSwdenkiminfo	- print header information for application image
4001c609719bSwdenkconinfo - print console devices and informations
4002c609719bSwdenkide	- IDE sub-system
4003c609719bSwdenkloop	- infinite loop on address range
400456523f12Swdenkloopw	- infinite write loop on address range
4005c609719bSwdenkmtest	- simple RAM test
4006c609719bSwdenkicache	- enable or disable instruction cache
4007c609719bSwdenkdcache	- enable or disable data cache
4008c609719bSwdenkreset	- Perform RESET of the CPU
4009c609719bSwdenkecho	- echo args to console
4010c609719bSwdenkversion - print monitor version
4011c609719bSwdenkhelp	- print online help
4012c609719bSwdenk?	- alias for 'help'
4013c609719bSwdenk
4014c609719bSwdenk
4015c609719bSwdenkMonitor Commands - Detailed Description:
4016c609719bSwdenk========================================
4017c609719bSwdenk
4018c609719bSwdenkTODO.
4019c609719bSwdenk
4020c609719bSwdenkFor now: just type "help <command>".
4021c609719bSwdenk
4022c609719bSwdenk
4023c609719bSwdenkEnvironment Variables:
4024c609719bSwdenk======================
4025c609719bSwdenk
4026c609719bSwdenkU-Boot supports user configuration using Environment Variables which
4027c609719bSwdenkcan be made persistent by saving to Flash memory.
4028c609719bSwdenk
4029c609719bSwdenkEnvironment Variables are set using "setenv", printed using
4030c609719bSwdenk"printenv", and saved to Flash using "saveenv". Using "setenv"
4031c609719bSwdenkwithout a value can be used to delete a variable from the
4032c609719bSwdenkenvironment. As long as you don't save the environment you are
4033c609719bSwdenkworking with an in-memory copy. In case the Flash area containing the
4034c609719bSwdenkenvironment is erased by accident, a default environment is provided.
4035c609719bSwdenk
4036c96f86eeSWolfgang DenkSome configuration options can be set using Environment Variables.
4037c96f86eeSWolfgang Denk
4038c96f86eeSWolfgang DenkList of environment variables (most likely not complete):
4039c609719bSwdenk
4040c609719bSwdenk  baudrate	- see CONFIG_BAUDRATE
4041c609719bSwdenk
4042c609719bSwdenk  bootdelay	- see CONFIG_BOOTDELAY
4043c609719bSwdenk
4044c609719bSwdenk  bootcmd	- see CONFIG_BOOTCOMMAND
4045c609719bSwdenk
4046c609719bSwdenk  bootargs	- Boot arguments when booting an RTOS image
4047c609719bSwdenk
4048c609719bSwdenk  bootfile	- Name of the image to load with TFTP
4049c609719bSwdenk
40507d721e34SBartlomiej Sieka  bootm_low	- Memory range available for image processing in the bootm
40517d721e34SBartlomiej Sieka		  command can be restricted. This variable is given as
40527d721e34SBartlomiej Sieka		  a hexadecimal number and defines lowest address allowed
40537d721e34SBartlomiej Sieka		  for use by the bootm command. See also "bootm_size"
40547d721e34SBartlomiej Sieka		  environment variable. Address defined by "bootm_low" is
40557d721e34SBartlomiej Sieka		  also the base of the initial memory mapping for the Linux
4056c3624e6eSGrant Likely		  kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4057c3624e6eSGrant Likely		  bootm_mapsize.
4058c3624e6eSGrant Likely
4059c3624e6eSGrant Likely  bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4060c3624e6eSGrant Likely		  This variable is given as a hexadecimal number and it
4061c3624e6eSGrant Likely		  defines the size of the memory region starting at base
4062c3624e6eSGrant Likely		  address bootm_low that is accessible by the Linux kernel
4063c3624e6eSGrant Likely		  during early boot.  If unset, CONFIG_SYS_BOOTMAPSZ is used
4064c3624e6eSGrant Likely		  as the default value if it is defined, and bootm_size is
4065c3624e6eSGrant Likely		  used otherwise.
40667d721e34SBartlomiej Sieka
40677d721e34SBartlomiej Sieka  bootm_size	- Memory range available for image processing in the bootm
40687d721e34SBartlomiej Sieka		  command can be restricted. This variable is given as
40697d721e34SBartlomiej Sieka		  a hexadecimal number and defines the size of the region
40707d721e34SBartlomiej Sieka		  allowed for use by the bootm command. See also "bootm_low"
40717d721e34SBartlomiej Sieka		  environment variable.
40727d721e34SBartlomiej Sieka
40734bae9090SBartlomiej Sieka  updatefile	- Location of the software update file on a TFTP server, used
40744bae9090SBartlomiej Sieka		  by the automatic software update feature. Please refer to
40754bae9090SBartlomiej Sieka		  documentation in doc/README.update for more details.
40764bae9090SBartlomiej Sieka
4077c609719bSwdenk  autoload	- if set to "no" (any string beginning with 'n'),
4078c609719bSwdenk		  "bootp" will just load perform a lookup of the
4079c609719bSwdenk		  configuration from the BOOTP server, but not try to
4080c609719bSwdenk		  load any image using TFTP
4081c609719bSwdenk
4082c609719bSwdenk  autostart	- if set to "yes", an image loaded using the "bootp",
4083c609719bSwdenk		  "rarpboot", "tftpboot" or "diskboot" commands will
4084c609719bSwdenk		  be automatically started (by internally calling
4085c609719bSwdenk		  "bootm")
4086c609719bSwdenk
40874a6fd34bSwdenk		  If set to "no", a standalone image passed to the
40884a6fd34bSwdenk		  "bootm" command will be copied to the load address
40894a6fd34bSwdenk		  (and eventually uncompressed), but NOT be started.
40904a6fd34bSwdenk		  This can be used to load and uncompress arbitrary
40914a6fd34bSwdenk		  data.
40924a6fd34bSwdenk
4093a28afca5SDavid A. Long  fdt_high	- if set this restricts the maximum address that the
4094a28afca5SDavid A. Long		  flattened device tree will be copied into upon boot.
4095fa34f6b2SShawn Guo		  For example, if you have a system with 1 GB memory
4096fa34f6b2SShawn Guo		  at physical address 0x10000000, while Linux kernel
4097fa34f6b2SShawn Guo		  only recognizes the first 704 MB as low memory, you
4098fa34f6b2SShawn Guo		  may need to set fdt_high as 0x3C000000 to have the
4099fa34f6b2SShawn Guo		  device tree blob be copied to the maximum address
4100fa34f6b2SShawn Guo		  of the 704 MB low memory, so that Linux kernel can
4101fa34f6b2SShawn Guo		  access it during the boot procedure.
4102fa34f6b2SShawn Guo
4103a28afca5SDavid A. Long		  If this is set to the special value 0xFFFFFFFF then
4104a28afca5SDavid A. Long		  the fdt will not be copied at all on boot.  For this
4105a28afca5SDavid A. Long		  to work it must reside in writable memory, have
4106a28afca5SDavid A. Long		  sufficient padding on the end of it for u-boot to
4107a28afca5SDavid A. Long		  add the information it needs into it, and the memory
4108a28afca5SDavid A. Long		  must be accessible by the kernel.
4109a28afca5SDavid A. Long
4110eea63e05SSimon Glass  fdtcontroladdr- if set this is the address of the control flattened
4111eea63e05SSimon Glass		  device tree used by U-Boot when CONFIG_OF_CONTROL is
4112eea63e05SSimon Glass		  defined.
4113eea63e05SSimon Glass
411417ea1177Swdenk  i2cfast	- (PPC405GP|PPC405EP only)
411517ea1177Swdenk		  if set to 'y' configures Linux I2C driver for fast
411617ea1177Swdenk		  mode (400kHZ). This environment variable is used in
411717ea1177Swdenk		  initialization code. So, for changes to be effective
411817ea1177Swdenk		  it must be saved and board must be reset.
411917ea1177Swdenk
4120c609719bSwdenk  initrd_high	- restrict positioning of initrd images:
4121c609719bSwdenk		  If this variable is not set, initrd images will be
4122c609719bSwdenk		  copied to the highest possible address in RAM; this
4123c609719bSwdenk		  is usually what you want since it allows for
4124c609719bSwdenk		  maximum initrd size. If for some reason you want to
4125c609719bSwdenk		  make sure that the initrd image is loaded below the
41266d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		  CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4127c609719bSwdenk		  variable to a value of "no" or "off" or "0".
4128c609719bSwdenk		  Alternatively, you can set it to a maximum upper
4129c609719bSwdenk		  address to use (U-Boot will still check that it
4130c609719bSwdenk		  does not overwrite the U-Boot stack and data).
4131c609719bSwdenk
4132c609719bSwdenk		  For instance, when you have a system with 16 MB
41337152b1d0Swdenk		  RAM, and want to reserve 4 MB from use by Linux,
4134c609719bSwdenk		  you can do this by adding "mem=12M" to the value of
4135c609719bSwdenk		  the "bootargs" variable. However, now you must make
41367152b1d0Swdenk		  sure that the initrd image is placed in the first
4137c609719bSwdenk		  12 MB as well - this can be done with
4138c609719bSwdenk
4139c609719bSwdenk		  setenv initrd_high 00c00000
4140c609719bSwdenk
414138b99261Swdenk		  If you set initrd_high to 0xFFFFFFFF, this is an
414238b99261Swdenk		  indication to U-Boot that all addresses are legal
414338b99261Swdenk		  for the Linux kernel, including addresses in flash
414438b99261Swdenk		  memory. In this case U-Boot will NOT COPY the
414538b99261Swdenk		  ramdisk at all. This may be useful to reduce the
414638b99261Swdenk		  boot time on your system, but requires that this
414738b99261Swdenk		  feature is supported by your Linux kernel.
414838b99261Swdenk
4149c609719bSwdenk  ipaddr	- IP address; needed for tftpboot command
4150c609719bSwdenk
4151c609719bSwdenk  loadaddr	- Default load address for commands like "bootp",
4152dc7c9a1aSwdenk		  "rarpboot", "tftpboot", "loadb" or "diskboot"
4153c609719bSwdenk
4154c609719bSwdenk  loads_echo	- see CONFIG_LOADS_ECHO
4155c609719bSwdenk
4156c609719bSwdenk  serverip	- TFTP server IP address; needed for tftpboot command
4157c609719bSwdenk
4158c609719bSwdenk  bootretry	- see CONFIG_BOOT_RETRY_TIME
4159c609719bSwdenk
4160c609719bSwdenk  bootdelaykey	- see CONFIG_AUTOBOOT_DELAY_STR
4161c609719bSwdenk
4162c609719bSwdenk  bootstopkey	- see CONFIG_AUTOBOOT_STOP_STR
4163c609719bSwdenk
4164e2a53458SMike Frysinger  ethprime	- controls which interface is used first.
4165a3d991bdSwdenk
4166e2a53458SMike Frysinger  ethact	- controls which interface is currently active.
4167e2a53458SMike Frysinger		  For example you can do the following
4168a3d991bdSwdenk
416948690d80SHeiko Schocher		  => setenv ethact FEC
417048690d80SHeiko Schocher		  => ping 192.168.0.1 # traffic sent on FEC
417148690d80SHeiko Schocher		  => setenv ethact SCC
417248690d80SHeiko Schocher		  => ping 10.0.0.1 # traffic sent on SCC
4173a3d991bdSwdenk
4174e1692577SMatthias Fuchs  ethrotate	- When set to "no" U-Boot does not go through all
4175e1692577SMatthias Fuchs		  available network interfaces.
4176e1692577SMatthias Fuchs		  It just stays at the currently selected interface.
4177e1692577SMatthias Fuchs
4178a3d991bdSwdenk  netretry	- When set to "no" each network operation will
4179a3d991bdSwdenk		  either succeed or fail without retrying.
41806e592385Swdenk		  When set to "once" the network operation will
41816e592385Swdenk		  fail when all the available network interfaces
41826e592385Swdenk		  are tried once without success.
4183a3d991bdSwdenk		  Useful on scripts which control the retry operation
4184a3d991bdSwdenk		  themselves.
4185a3d991bdSwdenk
4186b4e2f89dSJean-Christophe PLAGNIOL-VILLARD  npe_ucode	- set load address for the NPE microcode
4187a1cf027aSJean-Christophe PLAGNIOL-VILLARD
4188b445bbb4SJeremiah Mahler  silent_linux  - If set then Linux will be told to boot silently, by
41898d51aacdSSimon Glass		  changing the console to be empty. If "yes" it will be
41908d51aacdSSimon Glass		  made silent. If "no" it will not be made silent. If
41918d51aacdSSimon Glass		  unset, then it will be made silent if the U-Boot console
41928d51aacdSSimon Glass		  is silent.
41938d51aacdSSimon Glass
4194f5fb7346SAlbert ARIBAUD \(3ADEV\)  tftpsrcp	- If this is set, the value is used for TFTP's
4195ecb0ccd9SWolfgang Denk		  UDP source port.
4196ecb0ccd9SWolfgang Denk
4197f5fb7346SAlbert ARIBAUD \(3ADEV\)  tftpdstp	- If this is set, the value is used for TFTP's UDP
419828cb9375SWolfgang Denk		  destination port instead of the Well Know Port 69.
419928cb9375SWolfgang Denk
4200c96f86eeSWolfgang Denk  tftpblocksize - Block size to use for TFTP transfers; if not set,
4201c96f86eeSWolfgang Denk		  we use the TFTP server's default block size
4202c96f86eeSWolfgang Denk
4203c96f86eeSWolfgang Denk  tftptimeout	- Retransmission timeout for TFTP packets (in milli-
4204c96f86eeSWolfgang Denk		  seconds, minimum value is 1000 = 1 second). Defines
4205c96f86eeSWolfgang Denk		  when a packet is considered to be lost so it has to
4206c96f86eeSWolfgang Denk		  be retransmitted. The default is 5000 = 5 seconds.
4207c96f86eeSWolfgang Denk		  Lowering this value may make downloads succeed
4208c96f86eeSWolfgang Denk		  faster in networks with high packet loss rates or
4209c96f86eeSWolfgang Denk		  with unreliable TFTP servers.
4210c96f86eeSWolfgang Denk
4211f5fb7346SAlbert ARIBAUD \(3ADEV\)  tftptimeoutcountmax	- maximum count of TFTP timeouts (no
4212f5fb7346SAlbert ARIBAUD \(3ADEV\)		  unit, minimum value = 0). Defines how many timeouts
4213f5fb7346SAlbert ARIBAUD \(3ADEV\)		  can happen during a single file transfer before that
4214f5fb7346SAlbert ARIBAUD \(3ADEV\)		  transfer is aborted. The default is 10, and 0 means
4215f5fb7346SAlbert ARIBAUD \(3ADEV\)		  'no timeouts allowed'. Increasing this value may help
4216f5fb7346SAlbert ARIBAUD \(3ADEV\)		  downloads succeed with high packet loss rates, or with
4217f5fb7346SAlbert ARIBAUD \(3ADEV\)		  unreliable TFTP servers or client hardware.
4218f5fb7346SAlbert ARIBAUD \(3ADEV\)
4219a3d991bdSwdenk  vlan		- When set to a value < 4095 the traffic over
422011ccc33fSMarcel Ziswiler		  Ethernet is encapsulated/received over 802.1q
4221a3d991bdSwdenk		  VLAN tagged frames.
4222c609719bSwdenk
422350768f5bSAlexandre Messier  bootpretryperiod	- Period during which BOOTP/DHCP sends retries.
422450768f5bSAlexandre Messier		  Unsigned value, in milliseconds. If not set, the period will
422550768f5bSAlexandre Messier		  be either the default (28000), or a value based on
422650768f5bSAlexandre Messier		  CONFIG_NET_RETRY_COUNT, if defined. This value has
422750768f5bSAlexandre Messier		  precedence over the valu based on CONFIG_NET_RETRY_COUNT.
422850768f5bSAlexandre Messier
4229dc0b7b0eSJason HobbsThe following image location variables contain the location of images
4230dc0b7b0eSJason Hobbsused in booting. The "Image" column gives the role of the image and is
4231dc0b7b0eSJason Hobbsnot an environment variable name. The other columns are environment
4232dc0b7b0eSJason Hobbsvariable names. "File Name" gives the name of the file on a TFTP
4233dc0b7b0eSJason Hobbsserver, "RAM Address" gives the location in RAM the image will be
4234dc0b7b0eSJason Hobbsloaded to, and "Flash Location" gives the image's address in NOR
4235dc0b7b0eSJason Hobbsflash or offset in NAND flash.
4236dc0b7b0eSJason Hobbs
4237dc0b7b0eSJason Hobbs*Note* - these variables don't have to be defined for all boards, some
4238aed9fed9SFabio Estevamboards currently use other variables for these purposes, and some
4239dc0b7b0eSJason Hobbsboards use these variables for other purposes.
4240dc0b7b0eSJason Hobbs
4241dc0b7b0eSJason HobbsImage		    File Name	     RAM Address       Flash Location
4242dc0b7b0eSJason Hobbs-----		    ---------	     -----------       --------------
4243dc0b7b0eSJason Hobbsu-boot		    u-boot	     u-boot_addr_r     u-boot_addr
4244dc0b7b0eSJason HobbsLinux kernel	    bootfile	     kernel_addr_r     kernel_addr
4245dc0b7b0eSJason Hobbsdevice tree blob    fdtfile	     fdt_addr_r	       fdt_addr
4246dc0b7b0eSJason Hobbsramdisk		    ramdiskfile	     ramdisk_addr_r    ramdisk_addr
4247dc0b7b0eSJason Hobbs
4248c609719bSwdenkThe following environment variables may be used and automatically
4249c609719bSwdenkupdated by the network boot commands ("bootp" and "rarpboot"),
4250c609719bSwdenkdepending the information provided by your boot server:
4251c609719bSwdenk
4252c609719bSwdenk  bootfile	- see above
4253c609719bSwdenk  dnsip		- IP address of your Domain Name Server
4254fe389a82Sstroese  dnsip2	- IP address of your secondary Domain Name Server
4255c609719bSwdenk  gatewayip	- IP address of the Gateway (Router) to use
4256c609719bSwdenk  hostname	- Target hostname
4257c609719bSwdenk  ipaddr	- see above
4258c609719bSwdenk  netmask	- Subnet Mask
4259c609719bSwdenk  rootpath	- Pathname of the root filesystem on the NFS server
4260c609719bSwdenk  serverip	- see above
4261c609719bSwdenk
4262c609719bSwdenk
4263c609719bSwdenkThere are two special Environment Variables:
4264c609719bSwdenk
4265c609719bSwdenk  serial#	- contains hardware identification information such
4266c609719bSwdenk		  as type string and/or serial number
4267c609719bSwdenk  ethaddr	- Ethernet address
4268c609719bSwdenk
4269c609719bSwdenkThese variables can be set only once (usually during manufacturing of
4270c609719bSwdenkthe board). U-Boot refuses to delete or overwrite these variables
4271c609719bSwdenkonce they have been set once.
4272c609719bSwdenk
4273c609719bSwdenk
4274c1551ea8SstroeseFurther special Environment Variables:
4275c1551ea8Sstroese
4276c1551ea8Sstroese  ver		- Contains the U-Boot version string as printed
4277c1551ea8Sstroese		  with the "version" command. This variable is
4278c1551ea8Sstroese		  readonly (see CONFIG_VERSION_VARIABLE).
4279c1551ea8Sstroese
4280c1551ea8Sstroese
4281c609719bSwdenkPlease note that changes to some configuration parameters may take
4282c609719bSwdenkonly effect after the next boot (yes, that's just like Windoze :-).
4283c609719bSwdenk
4284c609719bSwdenk
4285170ab110SJoe HershbergerCallback functions for environment variables:
4286170ab110SJoe Hershberger---------------------------------------------
4287170ab110SJoe Hershberger
4288170ab110SJoe HershbergerFor some environment variables, the behavior of u-boot needs to change
4289b445bbb4SJeremiah Mahlerwhen their values are changed.  This functionality allows functions to
4290170ab110SJoe Hershbergerbe associated with arbitrary variables.  On creation, overwrite, or
4291170ab110SJoe Hershbergerdeletion, the callback will provide the opportunity for some side
4292170ab110SJoe Hershbergereffect to happen or for the change to be rejected.
4293170ab110SJoe Hershberger
4294170ab110SJoe HershbergerThe callbacks are named and associated with a function using the
4295170ab110SJoe HershbergerU_BOOT_ENV_CALLBACK macro in your board or driver code.
4296170ab110SJoe Hershberger
4297170ab110SJoe HershbergerThese callbacks are associated with variables in one of two ways.  The
4298170ab110SJoe Hershbergerstatic list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4299170ab110SJoe Hershbergerin the board configuration to a string that defines a list of
4300170ab110SJoe Hershbergerassociations.  The list must be in the following format:
4301170ab110SJoe Hershberger
4302170ab110SJoe Hershberger	entry = variable_name[:callback_name]
4303170ab110SJoe Hershberger	list = entry[,list]
4304170ab110SJoe Hershberger
4305170ab110SJoe HershbergerIf the callback name is not specified, then the callback is deleted.
4306170ab110SJoe HershbergerSpaces are also allowed anywhere in the list.
4307170ab110SJoe Hershberger
4308170ab110SJoe HershbergerCallbacks can also be associated by defining the ".callbacks" variable
4309170ab110SJoe Hershbergerwith the same list format above.  Any association in ".callbacks" will
4310170ab110SJoe Hershbergeroverride any association in the static list. You can define
4311170ab110SJoe HershbergerCONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4312b445bbb4SJeremiah Mahler".callbacks" environment variable in the default or embedded environment.
4313170ab110SJoe Hershberger
4314bdf1fe4eSJoe HershbergerIf CONFIG_REGEX is defined, the variable_name above is evaluated as a
4315bdf1fe4eSJoe Hershbergerregular expression. This allows multiple variables to be connected to
4316bdf1fe4eSJoe Hershbergerthe same callback without explicitly listing them all out.
4317bdf1fe4eSJoe Hershberger
4318170ab110SJoe Hershberger
4319f07771ccSwdenkCommand Line Parsing:
4320f07771ccSwdenk=====================
4321f07771ccSwdenk
4322f07771ccSwdenkThere are two different command line parsers available with U-Boot:
43237152b1d0Swdenkthe old "simple" one, and the much more powerful "hush" shell:
4324f07771ccSwdenk
4325f07771ccSwdenkOld, simple command line parser:
4326f07771ccSwdenk--------------------------------
4327f07771ccSwdenk
4328f07771ccSwdenk- supports environment variables (through setenv / saveenv commands)
4329f07771ccSwdenk- several commands on one line, separated by ';'
4330fe126d8bSWolfgang Denk- variable substitution using "... ${name} ..." syntax
4331f07771ccSwdenk- special characters ('$', ';') can be escaped by prefixing with '\',
4332f07771ccSwdenk  for example:
4333fe126d8bSWolfgang Denk	setenv bootcmd bootm \${address}
4334f07771ccSwdenk- You can also escape text by enclosing in single apostrophes, for example:
4335f07771ccSwdenk	setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4336f07771ccSwdenk
4337f07771ccSwdenkHush shell:
4338f07771ccSwdenk-----------
4339f07771ccSwdenk
4340f07771ccSwdenk- similar to Bourne shell, with control structures like
4341f07771ccSwdenk  if...then...else...fi, for...do...done; while...do...done,
4342f07771ccSwdenk  until...do...done, ...
4343f07771ccSwdenk- supports environment ("global") variables (through setenv / saveenv
4344f07771ccSwdenk  commands) and local shell variables (through standard shell syntax
4345f07771ccSwdenk  "name=value"); only environment variables can be used with "run"
4346f07771ccSwdenk  command
4347f07771ccSwdenk
4348f07771ccSwdenkGeneral rules:
4349f07771ccSwdenk--------------
4350f07771ccSwdenk
4351f07771ccSwdenk(1) If a command line (or an environment variable executed by a "run"
4352f07771ccSwdenk    command) contains several commands separated by semicolon, and
4353f07771ccSwdenk    one of these commands fails, then the remaining commands will be
4354f07771ccSwdenk    executed anyway.
4355f07771ccSwdenk
4356f07771ccSwdenk(2) If you execute several variables with one call to run (i. e.
435711ccc33fSMarcel Ziswiler    calling run with a list of variables as arguments), any failing
4358f07771ccSwdenk    command will cause "run" to terminate, i. e. the remaining
4359f07771ccSwdenk    variables are not executed.
4360f07771ccSwdenk
4361c609719bSwdenkNote for Redundant Ethernet Interfaces:
4362c609719bSwdenk=======================================
4363c609719bSwdenk
436411ccc33fSMarcel ZiswilerSome boards come with redundant Ethernet interfaces; U-Boot supports
4365c609719bSwdenksuch configurations and is capable of automatic selection of a
43667152b1d0Swdenk"working" interface when needed. MAC assignment works as follows:
4367c609719bSwdenk
4368c609719bSwdenkNetwork interfaces are numbered eth0, eth1, eth2, ... Corresponding
4369c609719bSwdenkMAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4370c609719bSwdenk"eth1addr" (=>eth1), "eth2addr", ...
4371c609719bSwdenk
4372c609719bSwdenkIf the network interface stores some valid MAC address (for instance
4373c609719bSwdenkin SROM), this is used as default address if there is NO correspon-
4374c609719bSwdenkding setting in the environment; if the corresponding environment
4375c609719bSwdenkvariable is set, this overrides the settings in the card; that means:
4376c609719bSwdenk
4377c609719bSwdenko If the SROM has a valid MAC address, and there is no address in the
4378c609719bSwdenk  environment, the SROM's address is used.
4379c609719bSwdenk
4380c609719bSwdenko If there is no valid address in the SROM, and a definition in the
4381c609719bSwdenk  environment exists, then the value from the environment variable is
4382c609719bSwdenk  used.
4383c609719bSwdenk
4384c609719bSwdenko If both the SROM and the environment contain a MAC address, and
4385c609719bSwdenk  both addresses are the same, this MAC address is used.
4386c609719bSwdenk
4387c609719bSwdenko If both the SROM and the environment contain a MAC address, and the
4388c609719bSwdenk  addresses differ, the value from the environment is used and a
4389c609719bSwdenk  warning is printed.
4390c609719bSwdenk
4391c609719bSwdenko If neither SROM nor the environment contain a MAC address, an error
4392bef1014bSJoe Hershberger  is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4393bef1014bSJoe Hershberger  a random, locally-assigned MAC is used.
4394c609719bSwdenk
4395ecee9324SBen WarrenIf Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4396ecee9324SBen Warrenwill be programmed into hardware as part of the initialization process.	 This
4397ecee9324SBen Warrenmay be skipped by setting the appropriate 'ethmacskip' environment variable.
4398ecee9324SBen WarrenThe naming convention is as follows:
4399ecee9324SBen Warren"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4400c609719bSwdenk
4401c609719bSwdenkImage Formats:
4402c609719bSwdenk==============
4403c609719bSwdenk
44043310c549SMarian BalakowiczU-Boot is capable of booting (and performing other auxiliary operations on)
44053310c549SMarian Balakowiczimages in two formats:
44063310c549SMarian Balakowicz
44073310c549SMarian BalakowiczNew uImage format (FIT)
44083310c549SMarian Balakowicz-----------------------
44093310c549SMarian Balakowicz
44103310c549SMarian BalakowiczFlexible and powerful format based on Flattened Image Tree -- FIT (similar
44113310c549SMarian Balakowiczto Flattened Device Tree). It allows the use of images with multiple
44123310c549SMarian Balakowiczcomponents (several kernels, ramdisks, etc.), with contents protected by
44133310c549SMarian BalakowiczSHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
44143310c549SMarian Balakowicz
44153310c549SMarian Balakowicz
44163310c549SMarian BalakowiczOld uImage format
44173310c549SMarian Balakowicz-----------------
44183310c549SMarian Balakowicz
44193310c549SMarian BalakowiczOld image format is based on binary files which can be basically anything,
44203310c549SMarian Balakowiczpreceded by a special header; see the definitions in include/image.h for
44213310c549SMarian Balakowiczdetails; basically, the header defines the following image properties:
4422c609719bSwdenk
4423c609719bSwdenk* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4424c609719bSwdenk  4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4425f5ed9e39SPeter Tyser  LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4426f5ed9e39SPeter Tyser  Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4427f5ed9e39SPeter Tyser  INTEGRITY).
4428daab59acSAndy Shevchenko* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
4429afc1ce82SMacpaul Lin  IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4430daab59acSAndy Shevchenko  Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4431c29fdfc1Swdenk* Compression Type (uncompressed, gzip, bzip2)
4432c609719bSwdenk* Load Address
4433c609719bSwdenk* Entry Point
4434c609719bSwdenk* Image Name
4435c609719bSwdenk* Image Timestamp
4436c609719bSwdenk
4437c609719bSwdenkThe header is marked by a special Magic Number, and both the header
4438c609719bSwdenkand the data portions of the image are secured against corruption by
4439c609719bSwdenkCRC32 checksums.
4440c609719bSwdenk
4441c609719bSwdenk
4442c609719bSwdenkLinux Support:
4443c609719bSwdenk==============
4444c609719bSwdenk
4445c609719bSwdenkAlthough U-Boot should support any OS or standalone application
44467152b1d0Swdenkeasily, the main focus has always been on Linux during the design of
4447c609719bSwdenkU-Boot.
4448c609719bSwdenk
4449c609719bSwdenkU-Boot includes many features that so far have been part of some
4450c609719bSwdenkspecial "boot loader" code within the Linux kernel. Also, any
4451c609719bSwdenk"initrd" images to be used are no longer part of one big Linux image;
4452c609719bSwdenkinstead, kernel and "initrd" are separate images. This implementation
44537152b1d0Swdenkserves several purposes:
4454c609719bSwdenk
4455c609719bSwdenk- the same features can be used for other OS or standalone
4456c609719bSwdenk  applications (for instance: using compressed images to reduce the
4457c609719bSwdenk  Flash memory footprint)
4458c609719bSwdenk
4459c609719bSwdenk- it becomes much easier to port new Linux kernel versions because
44607152b1d0Swdenk  lots of low-level, hardware dependent stuff are done by U-Boot
4461c609719bSwdenk
4462c609719bSwdenk- the same Linux kernel image can now be used with different "initrd"
4463c609719bSwdenk  images; of course this also means that different kernel images can
4464c609719bSwdenk  be run with the same "initrd". This makes testing easier (you don't
4465c609719bSwdenk  have to build a new "zImage.initrd" Linux image when you just
4466c609719bSwdenk  change a file in your "initrd"). Also, a field-upgrade of the
4467c609719bSwdenk  software is easier now.
4468c609719bSwdenk
4469c609719bSwdenk
4470c609719bSwdenkLinux HOWTO:
4471c609719bSwdenk============
4472c609719bSwdenk
4473c609719bSwdenkPorting Linux to U-Boot based systems:
4474c609719bSwdenk---------------------------------------
4475c609719bSwdenk
4476c609719bSwdenkU-Boot cannot save you from doing all the necessary modifications to
4477c609719bSwdenkconfigure the Linux device drivers for use with your target hardware
4478c609719bSwdenk(no, we don't intend to provide a full virtual machine interface to
4479c609719bSwdenkLinux :-).
4480c609719bSwdenk
4481a47a12beSStefan RoeseBut now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4482c609719bSwdenk
4483c609719bSwdenkJust make sure your machine specific header file (for instance
4484c609719bSwdenkinclude/asm-ppc/tqm8xx.h) includes the same definition of the Board
44851dc30693SMarkus HeidelbergInformation structure as we define in include/asm-<arch>/u-boot.h,
44861dc30693SMarkus Heidelbergand make sure that your definition of IMAP_ADDR uses the same value
44876d0f6bcfSJean-Christophe PLAGNIOL-VILLARDas your U-Boot configuration in CONFIG_SYS_IMMR.
4488c609719bSwdenk
44892eb31b13SSimon GlassNote that U-Boot now has a driver model, a unified model for drivers.
44902eb31b13SSimon GlassIf you are adding a new driver, plumb it into driver model. If there
44912eb31b13SSimon Glassis no uclass available, you are encouraged to create one. See
44922eb31b13SSimon Glassdoc/driver-model.
44932eb31b13SSimon Glass
4494c609719bSwdenk
4495c609719bSwdenkConfiguring the Linux kernel:
4496c609719bSwdenk-----------------------------
4497c609719bSwdenk
4498c609719bSwdenkNo specific requirements for U-Boot. Make sure you have some root
4499c609719bSwdenkdevice (initial ramdisk, NFS) for your target system.
4500c609719bSwdenk
4501c609719bSwdenk
4502c609719bSwdenkBuilding a Linux Image:
4503c609719bSwdenk-----------------------
4504c609719bSwdenk
450524ee89b9SwdenkWith U-Boot, "normal" build targets like "zImage" or "bzImage" are
450624ee89b9Swdenknot used. If you use recent kernel source, a new build target
450724ee89b9Swdenk"uImage" will exist which automatically builds an image usable by
450824ee89b9SwdenkU-Boot. Most older kernels also have support for a "pImage" target,
450924ee89b9Swdenkwhich was introduced for our predecessor project PPCBoot and uses a
451024ee89b9Swdenk100% compatible format.
4511c609719bSwdenk
4512c609719bSwdenkExample:
4513c609719bSwdenk
4514ab584d67SHolger Freyther	make TQM850L_defconfig
4515c609719bSwdenk	make oldconfig
4516c609719bSwdenk	make dep
451724ee89b9Swdenk	make uImage
4518c609719bSwdenk
451924ee89b9SwdenkThe "uImage" build target uses a special tool (in 'tools/mkimage') to
452024ee89b9Swdenkencapsulate a compressed Linux kernel image with header	 information,
452124ee89b9SwdenkCRC32 checksum etc. for use with U-Boot. This is what we are doing:
4522c609719bSwdenk
452324ee89b9Swdenk* build a standard "vmlinux" kernel image (in ELF binary format):
452424ee89b9Swdenk
452524ee89b9Swdenk* convert the kernel into a raw binary image:
452624ee89b9Swdenk
452724ee89b9Swdenk	${CROSS_COMPILE}-objcopy -O binary \
452824ee89b9Swdenk				 -R .note -R .comment \
452924ee89b9Swdenk				 -S vmlinux linux.bin
453024ee89b9Swdenk
453124ee89b9Swdenk* compress the binary image:
453224ee89b9Swdenk
453324ee89b9Swdenk	gzip -9 linux.bin
453424ee89b9Swdenk
453524ee89b9Swdenk* package compressed binary image for U-Boot:
453624ee89b9Swdenk
453724ee89b9Swdenk	mkimage -A ppc -O linux -T kernel -C gzip \
453824ee89b9Swdenk		-a 0 -e 0 -n "Linux Kernel Image" \
453924ee89b9Swdenk		-d linux.bin.gz uImage
454024ee89b9Swdenk
454124ee89b9Swdenk
454224ee89b9SwdenkThe "mkimage" tool can also be used to create ramdisk images for use
454324ee89b9Swdenkwith U-Boot, either separated from the Linux kernel image, or
454424ee89b9Swdenkcombined into one file. "mkimage" encapsulates the images with a 64
454524ee89b9Swdenkbyte header containing information about target architecture,
454624ee89b9Swdenkoperating system, image type, compression method, entry points, time
454724ee89b9Swdenkstamp, CRC32 checksums, etc.
454824ee89b9Swdenk
454924ee89b9Swdenk"mkimage" can be called in two ways: to verify existing images and
455024ee89b9Swdenkprint the header information, or to build new images.
4551c609719bSwdenk
4552c609719bSwdenkIn the first form (with "-l" option) mkimage lists the information
4553c609719bSwdenkcontained in the header of an existing U-Boot image; this includes
4554c609719bSwdenkchecksum verification:
4555c609719bSwdenk
4556c609719bSwdenk	tools/mkimage -l image
4557c609719bSwdenk	  -l ==> list image header information
4558c609719bSwdenk
4559c609719bSwdenkThe second form (with "-d" option) is used to build a U-Boot image
4560c609719bSwdenkfrom a "data file" which is used as image payload:
4561c609719bSwdenk
4562c609719bSwdenk	tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4563c609719bSwdenk		      -n name -d data_file image
4564c609719bSwdenk	  -A ==> set architecture to 'arch'
4565c609719bSwdenk	  -O ==> set operating system to 'os'
4566c609719bSwdenk	  -T ==> set image type to 'type'
4567c609719bSwdenk	  -C ==> set compression type 'comp'
4568c609719bSwdenk	  -a ==> set load address to 'addr' (hex)
4569c609719bSwdenk	  -e ==> set entry point to 'ep' (hex)
4570c609719bSwdenk	  -n ==> set image name to 'name'
4571c609719bSwdenk	  -d ==> use image data from 'datafile'
4572c609719bSwdenk
457369459791SwdenkRight now, all Linux kernels for PowerPC systems use the same load
457469459791Swdenkaddress (0x00000000), but the entry point address depends on the
457569459791Swdenkkernel version:
4576c609719bSwdenk
4577c609719bSwdenk- 2.2.x kernels have the entry point at 0x0000000C,
457824ee89b9Swdenk- 2.3.x and later kernels have the entry point at 0x00000000.
4579c609719bSwdenk
4580c609719bSwdenkSo a typical call to build a U-Boot image would read:
4581c609719bSwdenk
458224ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
458324ee89b9Swdenk	> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4584a47a12beSStefan Roese	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
458524ee89b9Swdenk	> examples/uImage.TQM850L
458624ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4587c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4588c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
4589c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
4590c609719bSwdenk	Load Address: 0x00000000
459124ee89b9Swdenk	Entry Point:  0x00000000
4592c609719bSwdenk
4593c609719bSwdenkTo verify the contents of the image (or check for corruption):
4594c609719bSwdenk
459524ee89b9Swdenk	-> tools/mkimage -l examples/uImage.TQM850L
459624ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4597c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4598c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
4599c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
4600c609719bSwdenk	Load Address: 0x00000000
460124ee89b9Swdenk	Entry Point:  0x00000000
4602c609719bSwdenk
4603c609719bSwdenkNOTE: for embedded systems where boot time is critical you can trade
4604c609719bSwdenkspeed for memory and install an UNCOMPRESSED image instead: this
4605c609719bSwdenkneeds more space in Flash, but boots much faster since it does not
4606c609719bSwdenkneed to be uncompressed:
4607c609719bSwdenk
4608a47a12beSStefan Roese	-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
460924ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
461024ee89b9Swdenk	> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4611a47a12beSStefan Roese	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
461224ee89b9Swdenk	> examples/uImage.TQM850L-uncompressed
461324ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4614c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4615c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (uncompressed)
4616c609719bSwdenk	Data Size:    792160 Bytes = 773.59 kB = 0.76 MB
4617c609719bSwdenk	Load Address: 0x00000000
461824ee89b9Swdenk	Entry Point:  0x00000000
4619c609719bSwdenk
4620c609719bSwdenk
4621c609719bSwdenkSimilar you can build U-Boot images from a 'ramdisk.image.gz' file
4622c609719bSwdenkwhen your kernel is intended to use an initial ramdisk:
4623c609719bSwdenk
4624c609719bSwdenk	-> tools/mkimage -n 'Simple Ramdisk Image' \
4625c609719bSwdenk	> -A ppc -O linux -T ramdisk -C gzip \
4626c609719bSwdenk	> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4627c609719bSwdenk	Image Name:   Simple Ramdisk Image
4628c609719bSwdenk	Created:      Wed Jan 12 14:01:50 2000
4629c609719bSwdenk	Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
4630c609719bSwdenk	Data Size:    566530 Bytes = 553.25 kB = 0.54 MB
4631c609719bSwdenk	Load Address: 0x00000000
4632c609719bSwdenk	Entry Point:  0x00000000
4633c609719bSwdenk
4634a804b5ceSGuilherme Maciel FerreiraThe "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4635a804b5ceSGuilherme Maciel Ferreiraoption performs the converse operation of the mkimage's second form (the "-d"
4636a804b5ceSGuilherme Maciel Ferreiraoption). Given an image built by mkimage, the dumpimage extracts a "data file"
4637a804b5ceSGuilherme Maciel Ferreirafrom the image:
4638a804b5ceSGuilherme Maciel Ferreira
4639f41f5b7cSGuilherme Maciel Ferreira	tools/dumpimage -i image -T type -p position data_file
4640f41f5b7cSGuilherme Maciel Ferreira	  -i ==> extract from the 'image' a specific 'data_file'
4641f41f5b7cSGuilherme Maciel Ferreira	  -T ==> set image type to 'type'
4642f41f5b7cSGuilherme Maciel Ferreira	  -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
4643a804b5ceSGuilherme Maciel Ferreira
4644c609719bSwdenk
4645c609719bSwdenkInstalling a Linux Image:
4646c609719bSwdenk-------------------------
4647c609719bSwdenk
4648c609719bSwdenkTo downloading a U-Boot image over the serial (console) interface,
4649c609719bSwdenkyou must convert the image to S-Record format:
4650c609719bSwdenk
4651c609719bSwdenk	objcopy -I binary -O srec examples/image examples/image.srec
4652c609719bSwdenk
4653c609719bSwdenkThe 'objcopy' does not understand the information in the U-Boot
4654c609719bSwdenkimage header, so the resulting S-Record file will be relative to
4655c609719bSwdenkaddress 0x00000000. To load it to a given address, you need to
4656c609719bSwdenkspecify the target address as 'offset' parameter with the 'loads'
4657c609719bSwdenkcommand.
4658c609719bSwdenk
4659c609719bSwdenkExample: install the image to address 0x40100000 (which on the
4660c609719bSwdenkTQM8xxL is in the first Flash bank):
4661c609719bSwdenk
4662c609719bSwdenk	=> erase 40100000 401FFFFF
4663c609719bSwdenk
4664c609719bSwdenk	.......... done
4665c609719bSwdenk	Erased 8 sectors
4666c609719bSwdenk
4667c609719bSwdenk	=> loads 40100000
4668c609719bSwdenk	## Ready for S-Record download ...
4669c609719bSwdenk	~>examples/image.srec
4670c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4671c609719bSwdenk	...
4672c609719bSwdenk	15989 15990 15991 15992
4673c609719bSwdenk	[file transfer complete]
4674c609719bSwdenk	[connected]
4675c609719bSwdenk	## Start Addr = 0x00000000
4676c609719bSwdenk
4677c609719bSwdenk
4678c609719bSwdenkYou can check the success of the download using the 'iminfo' command;
4679c609719bSwdenkthis includes a checksum verification so you can be sure no data
4680c609719bSwdenkcorruption happened:
4681c609719bSwdenk
4682c609719bSwdenk	=> imi 40100000
4683c609719bSwdenk
4684c609719bSwdenk	## Checking Image at 40100000 ...
4685c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4686c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4687c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4688c609719bSwdenk	   Load Address: 00000000
4689c609719bSwdenk	   Entry Point:	 0000000c
4690c609719bSwdenk	   Verifying Checksum ... OK
4691c609719bSwdenk
4692c609719bSwdenk
4693c609719bSwdenkBoot Linux:
4694c609719bSwdenk-----------
4695c609719bSwdenk
4696c609719bSwdenkThe "bootm" command is used to boot an application that is stored in
4697c609719bSwdenkmemory (RAM or Flash). In case of a Linux kernel image, the contents
4698c609719bSwdenkof the "bootargs" environment variable is passed to the kernel as
4699c609719bSwdenkparameters. You can check and modify this variable using the
4700c609719bSwdenk"printenv" and "setenv" commands:
4701c609719bSwdenk
4702c609719bSwdenk
4703c609719bSwdenk	=> printenv bootargs
4704c609719bSwdenk	bootargs=root=/dev/ram
4705c609719bSwdenk
4706c609719bSwdenk	=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4707c609719bSwdenk
4708c609719bSwdenk	=> printenv bootargs
4709c609719bSwdenk	bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4710c609719bSwdenk
4711c609719bSwdenk	=> bootm 40020000
4712c609719bSwdenk	## Booting Linux kernel at 40020000 ...
4713c609719bSwdenk	   Image Name:	 2.2.13 for NFS on TQM850L
4714c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4715c609719bSwdenk	   Data Size:	 381681 Bytes = 372 kB = 0 MB
4716c609719bSwdenk	   Load Address: 00000000
4717c609719bSwdenk	   Entry Point:	 0000000c
4718c609719bSwdenk	   Verifying Checksum ... OK
4719c609719bSwdenk	   Uncompressing Kernel Image ... OK
4720c609719bSwdenk	Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
4721c609719bSwdenk	Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4722c609719bSwdenk	time_init: decrementer frequency = 187500000/60
4723c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
4724c609719bSwdenk	Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4725c609719bSwdenk	...
4726c609719bSwdenk
472711ccc33fSMarcel ZiswilerIf you want to boot a Linux kernel with initial RAM disk, you pass
47287152b1d0Swdenkthe memory addresses of both the kernel and the initrd image (PPBCOOT
4729c609719bSwdenkformat!) to the "bootm" command:
4730c609719bSwdenk
4731c609719bSwdenk	=> imi 40100000 40200000
4732c609719bSwdenk
4733c609719bSwdenk	## Checking Image at 40100000 ...
4734c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4735c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4736c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4737c609719bSwdenk	   Load Address: 00000000
4738c609719bSwdenk	   Entry Point:	 0000000c
4739c609719bSwdenk	   Verifying Checksum ... OK
4740c609719bSwdenk
4741c609719bSwdenk	## Checking Image at 40200000 ...
4742c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
4743c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
4744c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
4745c609719bSwdenk	   Load Address: 00000000
4746c609719bSwdenk	   Entry Point:	 00000000
4747c609719bSwdenk	   Verifying Checksum ... OK
4748c609719bSwdenk
4749c609719bSwdenk	=> bootm 40100000 40200000
4750c609719bSwdenk	## Booting Linux kernel at 40100000 ...
4751c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4752c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4753c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4754c609719bSwdenk	   Load Address: 00000000
4755c609719bSwdenk	   Entry Point:	 0000000c
4756c609719bSwdenk	   Verifying Checksum ... OK
4757c609719bSwdenk	   Uncompressing Kernel Image ... OK
4758c609719bSwdenk	## Loading RAMDisk Image at 40200000 ...
4759c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
4760c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
4761c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
4762c609719bSwdenk	   Load Address: 00000000
4763c609719bSwdenk	   Entry Point:	 00000000
4764c609719bSwdenk	   Verifying Checksum ... OK
4765c609719bSwdenk	   Loading Ramdisk ... OK
4766c609719bSwdenk	Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
4767c609719bSwdenk	Boot arguments: root=/dev/ram
4768c609719bSwdenk	time_init: decrementer frequency = 187500000/60
4769c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
4770c609719bSwdenk	...
4771c609719bSwdenk	RAMDISK: Compressed image found at block 0
4772c609719bSwdenk	VFS: Mounted root (ext2 filesystem).
4773c609719bSwdenk
4774c609719bSwdenk	bash#
4775c609719bSwdenk
47760267768eSMatthew McClintockBoot Linux and pass a flat device tree:
47770267768eSMatthew McClintock-----------
47780267768eSMatthew McClintock
47790267768eSMatthew McClintockFirst, U-Boot must be compiled with the appropriate defines. See the section
47800267768eSMatthew McClintocktitled "Linux Kernel Interface" above for a more in depth explanation. The
47810267768eSMatthew McClintockfollowing is an example of how to start a kernel and pass an updated
47820267768eSMatthew McClintockflat device tree:
47830267768eSMatthew McClintock
47840267768eSMatthew McClintock=> print oftaddr
47850267768eSMatthew McClintockoftaddr=0x300000
47860267768eSMatthew McClintock=> print oft
47870267768eSMatthew McClintockoft=oftrees/mpc8540ads.dtb
47880267768eSMatthew McClintock=> tftp $oftaddr $oft
47890267768eSMatthew McClintockSpeed: 1000, full duplex
47900267768eSMatthew McClintockUsing TSEC0 device
47910267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.101
47920267768eSMatthew McClintockFilename 'oftrees/mpc8540ads.dtb'.
47930267768eSMatthew McClintockLoad address: 0x300000
47940267768eSMatthew McClintockLoading: #
47950267768eSMatthew McClintockdone
47960267768eSMatthew McClintockBytes transferred = 4106 (100a hex)
47970267768eSMatthew McClintock=> tftp $loadaddr $bootfile
47980267768eSMatthew McClintockSpeed: 1000, full duplex
47990267768eSMatthew McClintockUsing TSEC0 device
48000267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.2
48010267768eSMatthew McClintockFilename 'uImage'.
48020267768eSMatthew McClintockLoad address: 0x200000
48030267768eSMatthew McClintockLoading:############
48040267768eSMatthew McClintockdone
48050267768eSMatthew McClintockBytes transferred = 1029407 (fb51f hex)
48060267768eSMatthew McClintock=> print loadaddr
48070267768eSMatthew McClintockloadaddr=200000
48080267768eSMatthew McClintock=> print oftaddr
48090267768eSMatthew McClintockoftaddr=0x300000
48100267768eSMatthew McClintock=> bootm $loadaddr - $oftaddr
48110267768eSMatthew McClintock## Booting image at 00200000 ...
48120267768eSMatthew McClintock   Image Name:	 Linux-2.6.17-dirty
48130267768eSMatthew McClintock   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
48140267768eSMatthew McClintock   Data Size:	 1029343 Bytes = 1005.2 kB
48150267768eSMatthew McClintock   Load Address: 00000000
48160267768eSMatthew McClintock   Entry Point:	 00000000
48170267768eSMatthew McClintock   Verifying Checksum ... OK
48180267768eSMatthew McClintock   Uncompressing Kernel Image ... OK
48190267768eSMatthew McClintockBooting using flat device tree at 0x300000
48200267768eSMatthew McClintockUsing MPC85xx ADS machine description
48210267768eSMatthew McClintockMemory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
48220267768eSMatthew McClintock[snip]
48230267768eSMatthew McClintock
48240267768eSMatthew McClintock
48256069ff26SwdenkMore About U-Boot Image Types:
48266069ff26Swdenk------------------------------
48276069ff26Swdenk
48286069ff26SwdenkU-Boot supports the following image types:
48296069ff26Swdenk
48306069ff26Swdenk   "Standalone Programs" are directly runnable in the environment
48316069ff26Swdenk	provided by U-Boot; it is expected that (if they behave
48326069ff26Swdenk	well) you can continue to work in U-Boot after return from
48336069ff26Swdenk	the Standalone Program.
48346069ff26Swdenk   "OS Kernel Images" are usually images of some Embedded OS which
48356069ff26Swdenk	will take over control completely. Usually these programs
48366069ff26Swdenk	will install their own set of exception handlers, device
48376069ff26Swdenk	drivers, set up the MMU, etc. - this means, that you cannot
48386069ff26Swdenk	expect to re-enter U-Boot except by resetting the CPU.
48396069ff26Swdenk   "RAMDisk Images" are more or less just data blocks, and their
48406069ff26Swdenk	parameters (address, size) are passed to an OS kernel that is
48416069ff26Swdenk	being started.
48426069ff26Swdenk   "Multi-File Images" contain several images, typically an OS
48436069ff26Swdenk	(Linux) kernel image and one or more data images like
48446069ff26Swdenk	RAMDisks. This construct is useful for instance when you want
48456069ff26Swdenk	to boot over the network using BOOTP etc., where the boot
48466069ff26Swdenk	server provides just a single image file, but you want to get
48476069ff26Swdenk	for instance an OS kernel and a RAMDisk image.
48486069ff26Swdenk
48496069ff26Swdenk	"Multi-File Images" start with a list of image sizes, each
48506069ff26Swdenk	image size (in bytes) specified by an "uint32_t" in network
48516069ff26Swdenk	byte order. This list is terminated by an "(uint32_t)0".
48526069ff26Swdenk	Immediately after the terminating 0 follow the images, one by
48536069ff26Swdenk	one, all aligned on "uint32_t" boundaries (size rounded up to
48546069ff26Swdenk	a multiple of 4 bytes).
48556069ff26Swdenk
48566069ff26Swdenk   "Firmware Images" are binary images containing firmware (like
48576069ff26Swdenk	U-Boot or FPGA images) which usually will be programmed to
48586069ff26Swdenk	flash memory.
48596069ff26Swdenk
48606069ff26Swdenk   "Script files" are command sequences that will be executed by
48616069ff26Swdenk	U-Boot's command interpreter; this feature is especially
48626069ff26Swdenk	useful when you configure U-Boot to use a real shell (hush)
48636069ff26Swdenk	as command interpreter.
48646069ff26Swdenk
486544f074c7SMarek VasutBooting the Linux zImage:
486644f074c7SMarek Vasut-------------------------
486744f074c7SMarek Vasut
486844f074c7SMarek VasutOn some platforms, it's possible to boot Linux zImage. This is done
486944f074c7SMarek Vasutusing the "bootz" command. The syntax of "bootz" command is the same
487044f074c7SMarek Vasutas the syntax of "bootm" command.
487144f074c7SMarek Vasut
48728ac28563STom RiniNote, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
4873017e1f3fSMarek Vasutkernel with raw initrd images. The syntax is slightly different, the
4874017e1f3fSMarek Vasutaddress of the initrd must be augmented by it's size, in the following
4875017e1f3fSMarek Vasutformat: "<initrd addres>:<initrd size>".
4876017e1f3fSMarek Vasut
4877c609719bSwdenk
4878c609719bSwdenkStandalone HOWTO:
4879c609719bSwdenk=================
4880c609719bSwdenk
4881c609719bSwdenkOne of the features of U-Boot is that you can dynamically load and
4882c609719bSwdenkrun "standalone" applications, which can use some resources of
4883c609719bSwdenkU-Boot like console I/O functions or interrupt services.
4884c609719bSwdenk
4885c609719bSwdenkTwo simple examples are included with the sources:
4886c609719bSwdenk
4887c609719bSwdenk"Hello World" Demo:
4888c609719bSwdenk-------------------
4889c609719bSwdenk
4890c609719bSwdenk'examples/hello_world.c' contains a small "Hello World" Demo
4891c609719bSwdenkapplication; it is automatically compiled when you build U-Boot.
4892c609719bSwdenkIt's configured to run at address 0x00040004, so you can play with it
4893c609719bSwdenklike that:
4894c609719bSwdenk
4895c609719bSwdenk	=> loads
4896c609719bSwdenk	## Ready for S-Record download ...
4897c609719bSwdenk	~>examples/hello_world.srec
4898c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
4899c609719bSwdenk	[file transfer complete]
4900c609719bSwdenk	[connected]
4901c609719bSwdenk	## Start Addr = 0x00040004
4902c609719bSwdenk
4903c609719bSwdenk	=> go 40004 Hello World! This is a test.
4904c609719bSwdenk	## Starting application at 0x00040004 ...
4905c609719bSwdenk	Hello World
4906c609719bSwdenk	argc = 7
4907c609719bSwdenk	argv[0] = "40004"
4908c609719bSwdenk	argv[1] = "Hello"
4909c609719bSwdenk	argv[2] = "World!"
4910c609719bSwdenk	argv[3] = "This"
4911c609719bSwdenk	argv[4] = "is"
4912c609719bSwdenk	argv[5] = "a"
4913c609719bSwdenk	argv[6] = "test."
4914c609719bSwdenk	argv[7] = "<NULL>"
4915c609719bSwdenk	Hit any key to exit ...
4916c609719bSwdenk
4917c609719bSwdenk	## Application terminated, rc = 0x0
4918c609719bSwdenk
4919c609719bSwdenkAnother example, which demonstrates how to register a CPM interrupt
4920c609719bSwdenkhandler with the U-Boot code, can be found in 'examples/timer.c'.
4921c609719bSwdenkHere, a CPM timer is set up to generate an interrupt every second.
4922c609719bSwdenkThe interrupt service routine is trivial, just printing a '.'
4923c609719bSwdenkcharacter, but this is just a demo program. The application can be
4924c609719bSwdenkcontrolled by the following keys:
4925c609719bSwdenk
4926c609719bSwdenk	? - print current values og the CPM Timer registers
4927c609719bSwdenk	b - enable interrupts and start timer
4928c609719bSwdenk	e - stop timer and disable interrupts
4929c609719bSwdenk	q - quit application
4930c609719bSwdenk
4931c609719bSwdenk	=> loads
4932c609719bSwdenk	## Ready for S-Record download ...
4933c609719bSwdenk	~>examples/timer.srec
4934c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
4935c609719bSwdenk	[file transfer complete]
4936c609719bSwdenk	[connected]
4937c609719bSwdenk	## Start Addr = 0x00040004
4938c609719bSwdenk
4939c609719bSwdenk	=> go 40004
4940c609719bSwdenk	## Starting application at 0x00040004 ...
4941c609719bSwdenk	TIMERS=0xfff00980
4942c609719bSwdenk	Using timer 1
4943c609719bSwdenk	  tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4944c609719bSwdenk
4945c609719bSwdenkHit 'b':
4946c609719bSwdenk	[q, b, e, ?] Set interval 1000000 us
4947c609719bSwdenk	Enabling timer
4948c609719bSwdenkHit '?':
4949c609719bSwdenk	[q, b, e, ?] ........
4950c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4951c609719bSwdenkHit '?':
4952c609719bSwdenk	[q, b, e, ?] .
4953c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4954c609719bSwdenkHit '?':
4955c609719bSwdenk	[q, b, e, ?] .
4956c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4957c609719bSwdenkHit '?':
4958c609719bSwdenk	[q, b, e, ?] .
4959c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4960c609719bSwdenkHit 'e':
4961c609719bSwdenk	[q, b, e, ?] ...Stopping timer
4962c609719bSwdenkHit 'q':
4963c609719bSwdenk	[q, b, e, ?] ## Application terminated, rc = 0x0
4964c609719bSwdenk
4965c609719bSwdenk
496685ec0bccSwdenkMinicom warning:
496785ec0bccSwdenk================
496885ec0bccSwdenk
49697152b1d0SwdenkOver time, many people have reported problems when trying to use the
497085ec0bccSwdenk"minicom" terminal emulation program for serial download. I (wd)
497185ec0bccSwdenkconsider minicom to be broken, and recommend not to use it. Under
4972f07771ccSwdenkUnix, I recommend to use C-Kermit for general purpose use (and
497385ec0bccSwdenkespecially for kermit binary protocol download ("loadb" command), and
4974e53515a2SKarl O. Pincuse "cu" for S-Record download ("loads" command).  See
4975e53515a2SKarl O. Pinchttp://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4976e53515a2SKarl O. Pincfor help with kermit.
4977e53515a2SKarl O. Pinc
497885ec0bccSwdenk
497952f52c14SwdenkNevertheless, if you absolutely want to use it try adding this
498052f52c14Swdenkconfiguration to your "File transfer protocols" section:
498152f52c14Swdenk
498252f52c14Swdenk	   Name	   Program			Name U/D FullScr IO-Red. Multi
498352f52c14Swdenk	X  kermit  /usr/bin/kermit -i -l %l -s	 Y    U	   Y	   N	  N
498452f52c14Swdenk	Y  kermit  /usr/bin/kermit -i -l %l -r	 N    D	   Y	   N	  N
498552f52c14Swdenk
498652f52c14Swdenk
4987c609719bSwdenkNetBSD Notes:
4988c609719bSwdenk=============
4989c609719bSwdenk
4990c609719bSwdenkStarting at version 0.9.2, U-Boot supports NetBSD both as host
4991c609719bSwdenk(build U-Boot) and target system (boots NetBSD/mpc8xx).
4992c609719bSwdenk
4993c609719bSwdenkBuilding requires a cross environment; it is known to work on
4994c609719bSwdenkNetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4995c609719bSwdenkneed gmake since the Makefiles are not compatible with BSD make).
4996c609719bSwdenkNote that the cross-powerpc package does not install include files;
4997c609719bSwdenkattempting to build U-Boot will fail because <machine/ansi.h> is
4998c609719bSwdenkmissing.  This file has to be installed and patched manually:
4999c609719bSwdenk
5000c609719bSwdenk	# cd /usr/pkg/cross/powerpc-netbsd/include
5001c609719bSwdenk	# mkdir powerpc
5002c609719bSwdenk	# ln -s powerpc machine
5003c609719bSwdenk	# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5004c609719bSwdenk	# ${EDIT} powerpc/ansi.h	## must remove __va_list, _BSD_VA_LIST
5005c609719bSwdenk
5006c609719bSwdenkNative builds *don't* work due to incompatibilities between native
5007c609719bSwdenkand U-Boot include files.
5008c609719bSwdenk
5009c609719bSwdenkBooting assumes that (the first part of) the image booted is a
5010c609719bSwdenkstage-2 loader which in turn loads and then invokes the kernel
5011c609719bSwdenkproper. Loader sources will eventually appear in the NetBSD source
5012c609719bSwdenktree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
50132a8af187Swdenkmeantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5014c609719bSwdenk
5015c609719bSwdenk
5016c609719bSwdenkImplementation Internals:
5017c609719bSwdenk=========================
5018c609719bSwdenk
5019c609719bSwdenkThe following is not intended to be a complete description of every
5020c609719bSwdenkimplementation detail. However, it should help to understand the
5021c609719bSwdenkinner workings of U-Boot and make it easier to port it to custom
5022c609719bSwdenkhardware.
5023c609719bSwdenk
5024c609719bSwdenk
5025c609719bSwdenkInitial Stack, Global Data:
5026c609719bSwdenk---------------------------
5027c609719bSwdenk
5028c609719bSwdenkThe implementation of U-Boot is complicated by the fact that U-Boot
5029c609719bSwdenkstarts running out of ROM (flash memory), usually without access to
5030c609719bSwdenksystem RAM (because the memory controller is not initialized yet).
5031c609719bSwdenkThis means that we don't have writable Data or BSS segments, and BSS
5032c609719bSwdenkis not initialized as zero. To be able to get a C environment working
5033c609719bSwdenkat all, we have to allocate at least a minimal stack. Implementation
5034c609719bSwdenkoptions for this are defined and restricted by the CPU used: Some CPU
5035c609719bSwdenkmodels provide on-chip memory (like the IMMR area on MPC8xx and
5036c609719bSwdenkMPC826x processors), on others (parts of) the data cache can be
5037c609719bSwdenklocked as (mis-) used as memory, etc.
5038c609719bSwdenk
50397152b1d0Swdenk	Chris Hallinan posted a good summary of these issues to the
50400668236bSWolfgang Denk	U-Boot mailing list:
504143d9616cSwdenk
504243d9616cSwdenk	Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
504343d9616cSwdenk	From: "Chris Hallinan" <clh@net1plus.com>
504443d9616cSwdenk	Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
504543d9616cSwdenk	...
504643d9616cSwdenk
504743d9616cSwdenk	Correct me if I'm wrong, folks, but the way I understand it
504843d9616cSwdenk	is this: Using DCACHE as initial RAM for Stack, etc, does not
504943d9616cSwdenk	require any physical RAM backing up the cache. The cleverness
505043d9616cSwdenk	is that the cache is being used as a temporary supply of
505143d9616cSwdenk	necessary storage before the SDRAM controller is setup. It's
505211ccc33fSMarcel Ziswiler	beyond the scope of this list to explain the details, but you
505343d9616cSwdenk	can see how this works by studying the cache architecture and
505443d9616cSwdenk	operation in the architecture and processor-specific manuals.
505543d9616cSwdenk
505643d9616cSwdenk	OCM is On Chip Memory, which I believe the 405GP has 4K. It
505743d9616cSwdenk	is another option for the system designer to use as an
505811ccc33fSMarcel Ziswiler	initial stack/RAM area prior to SDRAM being available. Either
505943d9616cSwdenk	option should work for you. Using CS 4 should be fine if your
506043d9616cSwdenk	board designers haven't used it for something that would
506143d9616cSwdenk	cause you grief during the initial boot! It is frequently not
506243d9616cSwdenk	used.
506343d9616cSwdenk
50646d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
506543d9616cSwdenk	with your processor/board/system design. The default value
506643d9616cSwdenk	you will find in any recent u-boot distribution in
50678a316c9bSStefan Roese	walnut.h should work for you. I'd set it to a value larger
506843d9616cSwdenk	than your SDRAM module. If you have a 64MB SDRAM module, set
506943d9616cSwdenk	it above 400_0000. Just make sure your board has no resources
507043d9616cSwdenk	that are supposed to respond to that address! That code in
507143d9616cSwdenk	start.S has been around a while and should work as is when
507243d9616cSwdenk	you get the config right.
507343d9616cSwdenk
507443d9616cSwdenk	-Chris Hallinan
507543d9616cSwdenk	DS4.COM, Inc.
507643d9616cSwdenk
5077c609719bSwdenkIt is essential to remember this, since it has some impact on the C
5078c609719bSwdenkcode for the initialization procedures:
5079c609719bSwdenk
5080c609719bSwdenk* Initialized global data (data segment) is read-only. Do not attempt
5081c609719bSwdenk  to write it.
5082c609719bSwdenk
5083b445bbb4SJeremiah Mahler* Do not use any uninitialized global data (or implicitly initialized
5084c609719bSwdenk  as zero data - BSS segment) at all - this is undefined, initiali-
50857152b1d0Swdenk  zation is performed later (when relocating to RAM).
5086c609719bSwdenk
5087c609719bSwdenk* Stack space is very limited. Avoid big data buffers or things like
5088c609719bSwdenk  that.
5089c609719bSwdenk
5090c609719bSwdenkHaving only the stack as writable memory limits means we cannot use
5091b445bbb4SJeremiah Mahlernormal global data to share information between the code. But it
5092c609719bSwdenkturned out that the implementation of U-Boot can be greatly
5093c609719bSwdenksimplified by making a global data structure (gd_t) available to all
5094c609719bSwdenkfunctions. We could pass a pointer to this data as argument to _all_
5095c609719bSwdenkfunctions, but this would bloat the code. Instead we use a feature of
5096c609719bSwdenkthe GCC compiler (Global Register Variables) to share the data: we
5097c609719bSwdenkplace a pointer (gd) to the global data into a register which we
5098c609719bSwdenkreserve for this purpose.
5099c609719bSwdenk
51007152b1d0SwdenkWhen choosing a register for such a purpose we are restricted by the
5101c609719bSwdenkrelevant  (E)ABI  specifications for the current architecture, and by
5102c609719bSwdenkGCC's implementation.
5103c609719bSwdenk
5104c609719bSwdenkFor PowerPC, the following registers have specific use:
5105c609719bSwdenk	R1:	stack pointer
5106e7670f6cSWolfgang Denk	R2:	reserved for system use
5107c609719bSwdenk	R3-R4:	parameter passing and return values
5108c609719bSwdenk	R5-R10: parameter passing
5109c609719bSwdenk	R13:	small data area pointer
5110c609719bSwdenk	R30:	GOT pointer
5111c609719bSwdenk	R31:	frame pointer
5112c609719bSwdenk
5113e6bee808SJoakim Tjernlund	(U-Boot also uses R12 as internal GOT pointer. r12
5114e6bee808SJoakim Tjernlund	is a volatile register so r12 needs to be reset when
5115e6bee808SJoakim Tjernlund	going back and forth between asm and C)
5116c609719bSwdenk
5117e7670f6cSWolfgang Denk    ==> U-Boot will use R2 to hold a pointer to the global data
5118c609719bSwdenk
5119c609719bSwdenk    Note: on PPC, we could use a static initializer (since the
5120c609719bSwdenk    address of the global data structure is known at compile time),
5121c609719bSwdenk    but it turned out that reserving a register results in somewhat
5122c609719bSwdenk    smaller code - although the code savings are not that big (on
5123c609719bSwdenk    average for all boards 752 bytes for the whole U-Boot image,
5124c609719bSwdenk    624 text + 127 data).
5125c609719bSwdenk
5126c609719bSwdenkOn ARM, the following registers are used:
5127c609719bSwdenk
5128c609719bSwdenk	R0:	function argument word/integer result
5129c609719bSwdenk	R1-R3:	function argument word
513012eba1b4SJeroen Hofstee	R9:	platform specific
513112eba1b4SJeroen Hofstee	R10:	stack limit (used only if stack checking is enabled)
5132c609719bSwdenk	R11:	argument (frame) pointer
5133c609719bSwdenk	R12:	temporary workspace
5134c609719bSwdenk	R13:	stack pointer
5135c609719bSwdenk	R14:	link register
5136c609719bSwdenk	R15:	program counter
5137c609719bSwdenk
513812eba1b4SJeroen Hofstee    ==> U-Boot will use R9 to hold a pointer to the global data
513912eba1b4SJeroen Hofstee
514012eba1b4SJeroen Hofstee    Note: on ARM, only R_ARM_RELATIVE relocations are supported.
5141c609719bSwdenk
51420df01fd3SThomas ChouOn Nios II, the ABI is documented here:
51430df01fd3SThomas Chou	http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
51440df01fd3SThomas Chou
51450df01fd3SThomas Chou    ==> U-Boot will use gp to hold a pointer to the global data
51460df01fd3SThomas Chou
51470df01fd3SThomas Chou    Note: on Nios II, we give "-G0" option to gcc and don't use gp
51480df01fd3SThomas Chou    to access small data sections, so gp is free.
51490df01fd3SThomas Chou
5150afc1ce82SMacpaul LinOn NDS32, the following registers are used:
5151afc1ce82SMacpaul Lin
5152afc1ce82SMacpaul Lin	R0-R1:	argument/return
5153afc1ce82SMacpaul Lin	R2-R5:	argument
5154afc1ce82SMacpaul Lin	R15:	temporary register for assembler
5155afc1ce82SMacpaul Lin	R16:	trampoline register
5156afc1ce82SMacpaul Lin	R28:	frame pointer (FP)
5157afc1ce82SMacpaul Lin	R29:	global pointer (GP)
5158afc1ce82SMacpaul Lin	R30:	link register (LP)
5159afc1ce82SMacpaul Lin	R31:	stack pointer (SP)
5160afc1ce82SMacpaul Lin	PC:	program counter (PC)
5161afc1ce82SMacpaul Lin
5162afc1ce82SMacpaul Lin    ==> U-Boot will use R10 to hold a pointer to the global data
5163afc1ce82SMacpaul Lin
5164d87080b7SWolfgang DenkNOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5165d87080b7SWolfgang Denkor current versions of GCC may "optimize" the code too much.
5166c609719bSwdenk
5167c609719bSwdenkMemory Management:
5168c609719bSwdenk------------------
5169c609719bSwdenk
5170c609719bSwdenkU-Boot runs in system state and uses physical addresses, i.e. the
5171c609719bSwdenkMMU is not used either for address mapping nor for memory protection.
5172c609719bSwdenk
5173c609719bSwdenkThe available memory is mapped to fixed addresses using the memory
5174c609719bSwdenkcontroller. In this process, a contiguous block is formed for each
5175c609719bSwdenkmemory type (Flash, SDRAM, SRAM), even when it consists of several
5176c609719bSwdenkphysical memory banks.
5177c609719bSwdenk
5178c609719bSwdenkU-Boot is installed in the first 128 kB of the first Flash bank (on
5179c609719bSwdenkTQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5180c609719bSwdenkbooting and sizing and initializing DRAM, the code relocates itself
5181c609719bSwdenkto the upper end of DRAM. Immediately below the U-Boot code some
51826d0f6bcfSJean-Christophe PLAGNIOL-VILLARDmemory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5183c609719bSwdenkconfiguration setting]. Below that, a structure with global Board
5184c609719bSwdenkInfo data is placed, followed by the stack (growing downward).
5185c609719bSwdenk
5186c609719bSwdenkAdditionally, some exception handler code is copied to the low 8 kB
5187c609719bSwdenkof DRAM (0x00000000 ... 0x00001FFF).
5188c609719bSwdenk
5189c609719bSwdenkSo a typical memory configuration with 16 MB of DRAM could look like
5190c609719bSwdenkthis:
5191c609719bSwdenk
5192c609719bSwdenk	0x0000 0000	Exception Vector code
5193c609719bSwdenk	      :
5194c609719bSwdenk	0x0000 1FFF
5195c609719bSwdenk	0x0000 2000	Free for Application Use
5196c609719bSwdenk	      :
5197c609719bSwdenk	      :
5198c609719bSwdenk
5199c609719bSwdenk	      :
5200c609719bSwdenk	      :
5201c609719bSwdenk	0x00FB FF20	Monitor Stack (Growing downward)
5202c609719bSwdenk	0x00FB FFAC	Board Info Data and permanent copy of global data
5203c609719bSwdenk	0x00FC 0000	Malloc Arena
5204c609719bSwdenk	      :
5205c609719bSwdenk	0x00FD FFFF
5206c609719bSwdenk	0x00FE 0000	RAM Copy of Monitor Code
5207c609719bSwdenk	...		eventually: LCD or video framebuffer
5208c609719bSwdenk	...		eventually: pRAM (Protected RAM - unchanged by reset)
5209c609719bSwdenk	0x00FF FFFF	[End of RAM]
5210c609719bSwdenk
5211c609719bSwdenk
5212c609719bSwdenkSystem Initialization:
5213c609719bSwdenk----------------------
5214c609719bSwdenk
5215c609719bSwdenkIn the reset configuration, U-Boot starts at the reset entry point
521611ccc33fSMarcel Ziswiler(on most PowerPC systems at address 0x00000100). Because of the reset
5217c609719bSwdenkconfiguration for CS0# this is a mirror of the on board Flash memory.
52187152b1d0SwdenkTo be able to re-map memory U-Boot then jumps to its link address.
5219c609719bSwdenkTo be able to implement the initialization code in C, a (small!)
5220c609719bSwdenkinitial stack is set up in the internal Dual Ported RAM (in case CPUs
52212eb48ff7SHeiko Schocherwhich provide such a feature like), or in a locked part of the data
52222eb48ff7SHeiko Schochercache. After that, U-Boot initializes the CPU core, the caches and
52232eb48ff7SHeiko Schocherthe SIU.
5224c609719bSwdenk
5225c609719bSwdenkNext, all (potentially) available memory banks are mapped using a
5226c609719bSwdenkpreliminary mapping. For example, we put them on 512 MB boundaries
5227c609719bSwdenk(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5228c609719bSwdenkon 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5229c609719bSwdenkprogrammed for SDRAM access. Using the temporary configuration, a
5230c609719bSwdenksimple memory test is run that determines the size of the SDRAM
5231c609719bSwdenkbanks.
5232c609719bSwdenk
5233c609719bSwdenkWhen there is more than one SDRAM bank, and the banks are of
52347152b1d0Swdenkdifferent size, the largest is mapped first. For equal size, the first
5235c609719bSwdenkbank (CS2#) is mapped first. The first mapping is always for address
5236c609719bSwdenk0x00000000, with any additional banks following immediately to create
5237c609719bSwdenkcontiguous memory starting from 0.
5238c609719bSwdenk
5239c609719bSwdenkThen, the monitor installs itself at the upper end of the SDRAM area
5240c609719bSwdenkand allocates memory for use by malloc() and for the global Board
5241c609719bSwdenkInfo data; also, the exception vector code is copied to the low RAM
5242c609719bSwdenkpages, and the final stack is set up.
5243c609719bSwdenk
5244c609719bSwdenkOnly after this relocation will you have a "normal" C environment;
5245c609719bSwdenkuntil that you are restricted in several ways, mostly because you are
5246c609719bSwdenkrunning from ROM, and because the code will have to be relocated to a
5247c609719bSwdenknew address in RAM.
5248c609719bSwdenk
5249c609719bSwdenk
5250c609719bSwdenkU-Boot Porting Guide:
5251c609719bSwdenk----------------------
5252c609719bSwdenk
5253c609719bSwdenk[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
52546aff3115Swdenklist, October 2002]
5255c609719bSwdenk
5256c609719bSwdenk
5257c609719bSwdenkint main(int argc, char *argv[])
5258c609719bSwdenk{
5259c609719bSwdenk	sighandler_t no_more_time;
5260c609719bSwdenk
5261c609719bSwdenk	signal(SIGALRM, no_more_time);
5262c609719bSwdenk	alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5263c609719bSwdenk
5264c609719bSwdenk	if (available_money > available_manpower) {
52656c3fef28SJerry Van Baren		Pay consultant to port U-Boot;
5266c609719bSwdenk		return 0;
5267c609719bSwdenk	}
5268c609719bSwdenk
5269c609719bSwdenk	Download latest U-Boot source;
5270c609719bSwdenk
52710668236bSWolfgang Denk	Subscribe to u-boot mailing list;
52726aff3115Swdenk
52736c3fef28SJerry Van Baren	if (clueless)
5274c609719bSwdenk		email("Hi, I am new to U-Boot, how do I get started?");
5275c609719bSwdenk
5276c609719bSwdenk	while (learning) {
5277c609719bSwdenk		Read the README file in the top level directory;
52787cb22f97Swdenk		Read http://www.denx.de/twiki/bin/view/DULG/Manual;
52796c3fef28SJerry Van Baren		Read applicable doc/*.README;
5280c609719bSwdenk		Read the source, Luke;
52816c3fef28SJerry Van Baren		/* find . -name "*.[chS]" | xargs grep -i <keyword> */
5282c609719bSwdenk	}
5283c609719bSwdenk
52846c3fef28SJerry Van Baren	if (available_money > toLocalCurrency ($2500))
52856c3fef28SJerry Van Baren		Buy a BDI3000;
52866c3fef28SJerry Van Baren	else
5287c609719bSwdenk		Add a lot of aggravation and time;
5288c609719bSwdenk
52896c3fef28SJerry Van Baren	if (a similar board exists) {	/* hopefully... */
52906c3fef28SJerry Van Baren		cp -a board/<similar> board/<myboard>
52916c3fef28SJerry Van Baren		cp include/configs/<similar>.h include/configs/<myboard>.h
52926c3fef28SJerry Van Baren	} else {
5293c609719bSwdenk		Create your own board support subdirectory;
52946c3fef28SJerry Van Baren		Create your own board include/configs/<myboard>.h file;
52956c3fef28SJerry Van Baren	}
52966c3fef28SJerry Van Baren	Edit new board/<myboard> files
52976c3fef28SJerry Van Baren	Edit new include/configs/<myboard>.h
5298c609719bSwdenk
52996c3fef28SJerry Van Baren	while (!accepted) {
5300c609719bSwdenk		while (!running) {
5301c609719bSwdenk			do {
5302c609719bSwdenk				Add / modify source code;
5303c609719bSwdenk			} until (compiles);
5304c609719bSwdenk			Debug;
5305c609719bSwdenk			if (clueless)
5306c609719bSwdenk				email("Hi, I am having problems...");
5307c609719bSwdenk		}
53086c3fef28SJerry Van Baren		Send patch file to the U-Boot email list;
53096c3fef28SJerry Van Baren		if (reasonable critiques)
53106c3fef28SJerry Van Baren			Incorporate improvements from email list code review;
53116c3fef28SJerry Van Baren		else
53126c3fef28SJerry Van Baren			Defend code as written;
53136c3fef28SJerry Van Baren	}
5314c609719bSwdenk
5315c609719bSwdenk	return 0;
5316c609719bSwdenk}
5317c609719bSwdenk
5318c609719bSwdenkvoid no_more_time (int sig)
5319c609719bSwdenk{
5320c609719bSwdenk      hire_a_guru();
5321c609719bSwdenk}
5322c609719bSwdenk
5323c609719bSwdenk
5324c609719bSwdenkCoding Standards:
5325c609719bSwdenk-----------------
5326c609719bSwdenk
5327c609719bSwdenkAll contributions to U-Boot should conform to the Linux kernel
53282c051651SDetlev Zundelcoding style; see the file "Documentation/CodingStyle" and the script
53297ca9296eSWolfgang Denk"scripts/Lindent" in your Linux kernel source directory.
5330c609719bSwdenk
53312c051651SDetlev ZundelSource files originating from a different project (for example the
53322c051651SDetlev ZundelMTD subsystem) are generally exempt from these guidelines and are not
5333b445bbb4SJeremiah Mahlerreformatted to ease subsequent migration to newer versions of those
53342c051651SDetlev Zundelsources.
53352c051651SDetlev Zundel
53362c051651SDetlev ZundelPlease note that U-Boot is implemented in C (and to some small parts in
53372c051651SDetlev ZundelAssembler); no C++ is used, so please do not use C++ style comments (//)
53382c051651SDetlev Zundelin your code.
5339c609719bSwdenk
5340c178d3daSwdenkPlease also stick to the following formatting rules:
5341180d3f74Swdenk- remove any trailing white space
53427ca9296eSWolfgang Denk- use TAB characters for indentation and vertical alignment, not spaces
5343180d3f74Swdenk- make sure NOT to use DOS '\r\n' line feeds
53447ca9296eSWolfgang Denk- do not add more than 2 consecutive empty lines to source files
5345180d3f74Swdenk- do not add trailing empty lines to source files
5346180d3f74Swdenk
5347c609719bSwdenkSubmissions which do not conform to the standards may be returned
5348c609719bSwdenkwith a request to reformat the changes.
5349c609719bSwdenk
5350c609719bSwdenk
5351c609719bSwdenkSubmitting Patches:
5352c609719bSwdenk-------------------
5353c609719bSwdenk
5354c609719bSwdenkSince the number of patches for U-Boot is growing, we need to
5355c609719bSwdenkestablish some rules. Submissions which do not conform to these rules
5356c609719bSwdenkmay be rejected, even when they contain important and valuable stuff.
5357c609719bSwdenk
53580d28f34bSMagnus LiljaPlease see http://www.denx.de/wiki/U-Boot/Patches for details.
5359218ca724SWolfgang Denk
53600668236bSWolfgang DenkPatches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
53610668236bSWolfgang Denksee http://lists.denx.de/mailman/listinfo/u-boot
53620668236bSWolfgang Denk
5363c609719bSwdenkWhen you send a patch, please include the following information with
5364c609719bSwdenkit:
5365c609719bSwdenk
5366c609719bSwdenk* For bug fixes: a description of the bug and how your patch fixes
5367c609719bSwdenk  this bug. Please try to include a way of demonstrating that the
5368c609719bSwdenk  patch actually fixes something.
5369c609719bSwdenk
5370c609719bSwdenk* For new features: a description of the feature and your
5371c609719bSwdenk  implementation.
5372c609719bSwdenk
5373c609719bSwdenk* A CHANGELOG entry as plaintext (separate from the patch)
5374c609719bSwdenk
53757207b366SRobert P. J. Day* For major contributions, add a MAINTAINERS file with your
53767207b366SRobert P. J. Day  information and associated file and directory references.
5377c609719bSwdenk
537827af930eSAlbert ARIBAUD* When you add support for a new board, don't forget to add a
537927af930eSAlbert ARIBAUD  maintainer e-mail address to the boards.cfg file, too.
5380c609719bSwdenk
5381c609719bSwdenk* If your patch adds new configuration options, don't forget to
5382c609719bSwdenk  document these in the README file.
5383c609719bSwdenk
5384218ca724SWolfgang Denk* The patch itself. If you are using git (which is *strongly*
5385218ca724SWolfgang Denk  recommended) you can easily generate the patch using the
53867ca9296eSWolfgang Denk  "git format-patch". If you then use "git send-email" to send it to
5387218ca724SWolfgang Denk  the U-Boot mailing list, you will avoid most of the common problems
5388218ca724SWolfgang Denk  with some other mail clients.
5389c609719bSwdenk
5390218ca724SWolfgang Denk  If you cannot use git, use "diff -purN OLD NEW". If your version of
5391218ca724SWolfgang Denk  diff does not support these options, then get the latest version of
5392218ca724SWolfgang Denk  GNU diff.
53936dff5529Swdenk
5394218ca724SWolfgang Denk  The current directory when running this command shall be the parent
5395218ca724SWolfgang Denk  directory of the U-Boot source tree (i. e. please make sure that
5396218ca724SWolfgang Denk  your patch includes sufficient directory information for the
5397218ca724SWolfgang Denk  affected files).
5398218ca724SWolfgang Denk
5399218ca724SWolfgang Denk  We prefer patches as plain text. MIME attachments are discouraged,
5400218ca724SWolfgang Denk  and compressed attachments must not be used.
5401c609719bSwdenk
540252f52c14Swdenk* If one logical set of modifications affects or creates several
540352f52c14Swdenk  files, all these changes shall be submitted in a SINGLE patch file.
540452f52c14Swdenk
540552f52c14Swdenk* Changesets that contain different, unrelated modifications shall be
540652f52c14Swdenk  submitted as SEPARATE patches, one patch per changeset.
540752f52c14Swdenk
540852f52c14Swdenk
5409c609719bSwdenkNotes:
5410c609719bSwdenk
54116de80f21SSimon Glass* Before sending the patch, run the buildman script on your patched
5412c609719bSwdenk  source tree and make sure that no errors or warnings are reported
5413c609719bSwdenk  for any of the boards.
5414c609719bSwdenk
5415c609719bSwdenk* Keep your modifications to the necessary minimum: A patch
5416c609719bSwdenk  containing several unrelated changes or arbitrary reformats will be
5417c609719bSwdenk  returned with a request to re-formatting / split it.
5418c609719bSwdenk
5419c609719bSwdenk* If you modify existing code, make sure that your new code does not
5420c609719bSwdenk  add to the memory footprint of the code ;-) Small is beautiful!
5421c609719bSwdenk  When adding new features, these should compile conditionally only
5422c609719bSwdenk  (using #ifdef), and the resulting code with the new feature
5423c609719bSwdenk  disabled must not need more memory than the old code without your
5424c609719bSwdenk  modification.
542590dc6704Swdenk
54260668236bSWolfgang Denk* Remember that there is a size limit of 100 kB per message on the
54270668236bSWolfgang Denk  u-boot mailing list. Bigger patches will be moderated. If they are
54280668236bSWolfgang Denk  reasonable and not too big, they will be acknowledged. But patches
54290668236bSWolfgang Denk  bigger than the size limit should be avoided.
5430