xref: /openbmc/u-boot/README (revision c055cee1)
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
31563b2316cSAshish Kumar- ARM Platform Bus Type(CCI):
31663b2316cSAshish Kumar		CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
31763b2316cSAshish Kumar		provides full cache coherency between two clusters of multi-core
31863b2316cSAshish Kumar		CPUs and I/O coherency for devices and I/O masters
31963b2316cSAshish Kumar
32063b2316cSAshish Kumar		CONFIG_SYS_FSL_HAS_CCI400
32163b2316cSAshish Kumar
32263b2316cSAshish Kumar		Defined For SoC that has cache coherent interconnect
32363b2316cSAshish Kumar		CCN-400
3247f6c2cbcSwdenk
325*c055cee1SAshish Kumar		CONFIG_SYS_FSL_HAS_CCN504
326*c055cee1SAshish Kumar
327*c055cee1SAshish Kumar		Defined for SoC that has cache coherent interconnect CCN-504
328*c055cee1SAshish Kumar
329c609719bSwdenkThe following options need to be configured:
330c609719bSwdenk
3312628114eSKim Phillips- CPU Type:	Define exactly one, e.g. CONFIG_MPC85XX.
332c609719bSwdenk
3332628114eSKim Phillips- Board Type:	Define exactly one, e.g. CONFIG_MPC8540ADS.
3346ccec449SWolfgang Denk
335cf946c6dSLei Wen- Marvell Family Member
336cf946c6dSLei Wen		CONFIG_SYS_MVFS		- define it if you want to enable
337cf946c6dSLei Wen					  multiple fs option at one time
338cf946c6dSLei Wen					  for marvell soc family
339cf946c6dSLei Wen
34066412c63SKumar Gala- 85xx CPU Options:
341ffd06e02SYork Sun		CONFIG_SYS_PPC64
342ffd06e02SYork Sun
343ffd06e02SYork Sun		Specifies that the core is a 64-bit PowerPC implementation (implements
344ffd06e02SYork Sun		the "64" category of the Power ISA). This is necessary for ePAPR
345ffd06e02SYork Sun		compliance, among other possible reasons.
346ffd06e02SYork Sun
34766412c63SKumar Gala		CONFIG_SYS_FSL_TBCLK_DIV
34866412c63SKumar Gala
34966412c63SKumar Gala		Defines the core time base clock divider ratio compared to the
35066412c63SKumar Gala		system clock.  On most PQ3 devices this is 8, on newer QorIQ
35166412c63SKumar Gala		devices it can be 16 or 32.  The ratio varies from SoC to Soc.
35266412c63SKumar Gala
3538f29084aSKumar Gala		CONFIG_SYS_FSL_PCIE_COMPAT
3548f29084aSKumar Gala
3558f29084aSKumar Gala		Defines the string to utilize when trying to match PCIe device
3568f29084aSKumar Gala		tree nodes for the given platform.
3578f29084aSKumar Gala
35833eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510
35933eee330SScott Wood
36033eee330SScott Wood		Enables a workaround for erratum A004510.  If set,
36133eee330SScott Wood		then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
36233eee330SScott Wood		CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
36333eee330SScott Wood
36433eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
36533eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
36633eee330SScott Wood
36733eee330SScott Wood		Defines one or two SoC revisions (low 8 bits of SVR)
36833eee330SScott Wood		for which the A004510 workaround should be applied.
36933eee330SScott Wood
37033eee330SScott Wood		The rest of SVR is either not relevant to the decision
37133eee330SScott Wood		of whether the erratum is present (e.g. p2040 versus
37233eee330SScott Wood		p2041) or is implied by the build target, which controls
37333eee330SScott Wood		whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
37433eee330SScott Wood
37533eee330SScott Wood		See Freescale App Note 4493 for more information about
37633eee330SScott Wood		this erratum.
37733eee330SScott Wood
37874fa22edSPrabhakar Kushwaha		CONFIG_A003399_NOR_WORKAROUND
37974fa22edSPrabhakar Kushwaha		Enables a workaround for IFC erratum A003399. It is only
380b445bbb4SJeremiah Mahler		required during NOR boot.
38174fa22edSPrabhakar Kushwaha
3829f074e67SPrabhakar Kushwaha		CONFIG_A008044_WORKAROUND
3839f074e67SPrabhakar Kushwaha		Enables a workaround for T1040/T1042 erratum A008044. It is only
384b445bbb4SJeremiah Mahler		required during NAND boot and valid for Rev 1.0 SoC revision
3859f074e67SPrabhakar Kushwaha
38633eee330SScott Wood		CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
38733eee330SScott Wood
38833eee330SScott Wood		This is the value to write into CCSR offset 0x18600
38933eee330SScott Wood		according to the A004510 workaround.
39033eee330SScott Wood
39164501c66SPriyanka Jain		CONFIG_SYS_FSL_DSP_DDR_ADDR
39264501c66SPriyanka Jain		This value denotes start offset of DDR memory which is
39364501c66SPriyanka Jain		connected exclusively to the DSP cores.
39464501c66SPriyanka Jain
395765b0bdbSPriyanka Jain		CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
396765b0bdbSPriyanka Jain		This value denotes start offset of M2 memory
397765b0bdbSPriyanka Jain		which is directly connected to the DSP core.
398765b0bdbSPriyanka Jain
39964501c66SPriyanka Jain		CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
40064501c66SPriyanka Jain		This value denotes start offset of M3 memory which is directly
40164501c66SPriyanka Jain		connected to the DSP core.
40264501c66SPriyanka Jain
403765b0bdbSPriyanka Jain		CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
404765b0bdbSPriyanka Jain		This value denotes start offset of DSP CCSR space.
405765b0bdbSPriyanka Jain
406b135991aSPriyanka Jain		CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
407b135991aSPriyanka Jain		Single Source Clock is clocking mode present in some of FSL SoC's.
408b135991aSPriyanka Jain		In this mode, a single differential clock is used to supply
409b135991aSPriyanka Jain		clocks to the sysclock, ddrclock and usbclock.
410b135991aSPriyanka Jain
411fb4a2409SAneesh Bansal		CONFIG_SYS_CPC_REINIT_F
412fb4a2409SAneesh Bansal		This CONFIG is defined when the CPC is configured as SRAM at the
413a187559eSBin Meng		time of U-Boot entry and is required to be re-initialized.
414fb4a2409SAneesh Bansal
415aade2004STang Yuantian		CONFIG_DEEP_SLEEP
416b445bbb4SJeremiah Mahler		Indicates this SoC supports deep sleep feature. If deep sleep is
417aade2004STang Yuantian		supported, core will start to execute uboot when wakes up.
418aade2004STang Yuantian
4196cb461b4SDaniel Schwierzeck- Generic CPU options:
4206cb461b4SDaniel Schwierzeck		CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
4216cb461b4SDaniel Schwierzeck
4226cb461b4SDaniel Schwierzeck		Defines the endianess of the CPU. Implementation of those
4236cb461b4SDaniel Schwierzeck		values is arch specific.
4246cb461b4SDaniel Schwierzeck
4255614e71bSYork Sun		CONFIG_SYS_FSL_DDR
4265614e71bSYork Sun		Freescale DDR driver in use. This type of DDR controller is
4275614e71bSYork Sun		found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
4285614e71bSYork Sun		SoCs.
4295614e71bSYork Sun
4305614e71bSYork Sun		CONFIG_SYS_FSL_DDR_ADDR
4315614e71bSYork Sun		Freescale DDR memory-mapped register base.
4325614e71bSYork Sun
4335614e71bSYork Sun		CONFIG_SYS_FSL_DDR_EMU
4345614e71bSYork Sun		Specify emulator support for DDR. Some DDR features such as
4355614e71bSYork Sun		deskew training are not available.
4365614e71bSYork Sun
4375614e71bSYork Sun		CONFIG_SYS_FSL_DDRC_GEN1
4385614e71bSYork Sun		Freescale DDR1 controller.
4395614e71bSYork Sun
4405614e71bSYork Sun		CONFIG_SYS_FSL_DDRC_GEN2
4415614e71bSYork Sun		Freescale DDR2 controller.
4425614e71bSYork Sun
4435614e71bSYork Sun		CONFIG_SYS_FSL_DDRC_GEN3
4445614e71bSYork Sun		Freescale DDR3 controller.
4455614e71bSYork Sun
44634e026f9SYork Sun		CONFIG_SYS_FSL_DDRC_GEN4
44734e026f9SYork Sun		Freescale DDR4 controller.
44834e026f9SYork Sun
4499ac4ffbdSYork Sun		CONFIG_SYS_FSL_DDRC_ARM_GEN3
4509ac4ffbdSYork Sun		Freescale DDR3 controller for ARM-based SoCs.
4519ac4ffbdSYork Sun
4525614e71bSYork Sun		CONFIG_SYS_FSL_DDR1
4535614e71bSYork Sun		Board config to use DDR1. It can be enabled for SoCs with
4545614e71bSYork Sun		Freescale DDR1 or DDR2 controllers, depending on the board
4555614e71bSYork Sun		implemetation.
4565614e71bSYork Sun
4575614e71bSYork Sun		CONFIG_SYS_FSL_DDR2
45862a3b7ddSRobert P. J. Day		Board config to use DDR2. It can be enabled for SoCs with
4595614e71bSYork Sun		Freescale DDR2 or DDR3 controllers, depending on the board
4605614e71bSYork Sun		implementation.
4615614e71bSYork Sun
4625614e71bSYork Sun		CONFIG_SYS_FSL_DDR3
4635614e71bSYork Sun		Board config to use DDR3. It can be enabled for SoCs with
46434e026f9SYork Sun		Freescale DDR3 or DDR3L controllers.
46534e026f9SYork Sun
46634e026f9SYork Sun		CONFIG_SYS_FSL_DDR3L
46734e026f9SYork Sun		Board config to use DDR3L. It can be enabled for SoCs with
46834e026f9SYork Sun		DDR3L controllers.
46934e026f9SYork Sun
47034e026f9SYork Sun		CONFIG_SYS_FSL_DDR4
47134e026f9SYork Sun		Board config to use DDR4. It can be enabled for SoCs with
47234e026f9SYork Sun		DDR4 controllers.
4735614e71bSYork Sun
4741b4175d6SPrabhakar Kushwaha		CONFIG_SYS_FSL_IFC_BE
4751b4175d6SPrabhakar Kushwaha		Defines the IFC controller register space as Big Endian
4761b4175d6SPrabhakar Kushwaha
4771b4175d6SPrabhakar Kushwaha		CONFIG_SYS_FSL_IFC_LE
4781b4175d6SPrabhakar Kushwaha		Defines the IFC controller register space as Little Endian
4791b4175d6SPrabhakar Kushwaha
4801c40707eSPrabhakar Kushwaha		CONFIG_SYS_FSL_IFC_CLK_DIV
4811c40707eSPrabhakar Kushwaha		Defines divider of platform clock(clock input to IFC controller).
4821c40707eSPrabhakar Kushwaha
483add63f94SPrabhakar Kushwaha		CONFIG_SYS_FSL_LBC_CLK_DIV
484add63f94SPrabhakar Kushwaha		Defines divider of platform clock(clock input to eLBC controller).
485add63f94SPrabhakar Kushwaha
486690e4258SPrabhakar Kushwaha		CONFIG_SYS_FSL_PBL_PBI
487690e4258SPrabhakar Kushwaha		It enables addition of RCW (Power on reset configuration) in built image.
488690e4258SPrabhakar Kushwaha		Please refer doc/README.pblimage for more details
489690e4258SPrabhakar Kushwaha
490690e4258SPrabhakar Kushwaha		CONFIG_SYS_FSL_PBL_RCW
491690e4258SPrabhakar Kushwaha		It adds PBI(pre-boot instructions) commands in u-boot build image.
492690e4258SPrabhakar Kushwaha		PBI commands can be used to configure SoC before it starts the execution.
493690e4258SPrabhakar Kushwaha		Please refer doc/README.pblimage for more details
494690e4258SPrabhakar Kushwaha
49589ad7be8SPrabhakar Kushwaha		CONFIG_SPL_FSL_PBL
49689ad7be8SPrabhakar Kushwaha		It adds a target to create boot binary having SPL binary in PBI format
49789ad7be8SPrabhakar Kushwaha		concatenated with u-boot binary.
49889ad7be8SPrabhakar Kushwaha
4994e5b1bd0SYork Sun		CONFIG_SYS_FSL_DDR_BE
5004e5b1bd0SYork Sun		Defines the DDR controller register space as Big Endian
5014e5b1bd0SYork Sun
5024e5b1bd0SYork Sun		CONFIG_SYS_FSL_DDR_LE
5034e5b1bd0SYork Sun		Defines the DDR controller register space as Little Endian
5044e5b1bd0SYork Sun
5056b9e309aSYork Sun		CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
5066b9e309aSYork Sun		Physical address from the view of DDR controllers. It is the
5076b9e309aSYork Sun		same as CONFIG_SYS_DDR_SDRAM_BASE for  all Power SoCs. But
5086b9e309aSYork Sun		it could be different for ARM SoCs.
5096b9e309aSYork Sun
5106b1e1254SYork Sun		CONFIG_SYS_FSL_DDR_INTLV_256B
5116b1e1254SYork Sun		DDR controller interleaving on 256-byte. This is a special
5126b1e1254SYork Sun		interleaving mode, handled by Dickens for Freescale layerscape
5136b1e1254SYork Sun		SoCs with ARM core.
5146b1e1254SYork Sun
5151d71efbbSYork Sun		CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
5161d71efbbSYork Sun		Number of controllers used as main memory.
5171d71efbbSYork Sun
5181d71efbbSYork Sun		CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
5191d71efbbSYork Sun		Number of controllers used for other than main memory.
5201d71efbbSYork Sun
52144937214SPrabhakar Kushwaha		CONFIG_SYS_FSL_HAS_DP_DDR
52244937214SPrabhakar Kushwaha		Defines the SoC has DP-DDR used for DPAA.
52344937214SPrabhakar Kushwaha
524028dbb8dSRuchika Gupta		CONFIG_SYS_FSL_SEC_BE
525028dbb8dSRuchika Gupta		Defines the SEC controller register space as Big Endian
526028dbb8dSRuchika Gupta
527028dbb8dSRuchika Gupta		CONFIG_SYS_FSL_SEC_LE
528028dbb8dSRuchika Gupta		Defines the SEC controller register space as Little Endian
529028dbb8dSRuchika Gupta
53092bbd64eSDaniel Schwierzeck- MIPS CPU options:
53192bbd64eSDaniel Schwierzeck		CONFIG_SYS_INIT_SP_OFFSET
53292bbd64eSDaniel Schwierzeck
53392bbd64eSDaniel Schwierzeck		Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
53492bbd64eSDaniel Schwierzeck		pointer. This is needed for the temporary stack before
53592bbd64eSDaniel Schwierzeck		relocation.
53692bbd64eSDaniel Schwierzeck
53792bbd64eSDaniel Schwierzeck		CONFIG_SYS_MIPS_CACHE_MODE
53892bbd64eSDaniel Schwierzeck
53992bbd64eSDaniel Schwierzeck		Cache operation mode for the MIPS CPU.
54092bbd64eSDaniel Schwierzeck		See also arch/mips/include/asm/mipsregs.h.
54192bbd64eSDaniel Schwierzeck		Possible values are:
54292bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_NO_WA
54392bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_WA
54492bbd64eSDaniel Schwierzeck			CONF_CM_UNCACHED
54592bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_NONCOHERENT
54692bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_CE
54792bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_COW
54892bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_CUW
54992bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_ACCELERATED
55092bbd64eSDaniel Schwierzeck
55192bbd64eSDaniel Schwierzeck		CONFIG_SYS_XWAY_EBU_BOOTCFG
55292bbd64eSDaniel Schwierzeck
55392bbd64eSDaniel Schwierzeck		Special option for Lantiq XWAY SoCs for booting from NOR flash.
55492bbd64eSDaniel Schwierzeck		See also arch/mips/cpu/mips32/start.S.
55592bbd64eSDaniel Schwierzeck
55692bbd64eSDaniel Schwierzeck		CONFIG_XWAY_SWAP_BYTES
55792bbd64eSDaniel Schwierzeck
55892bbd64eSDaniel Schwierzeck		Enable compilation of tools/xway-swap-bytes needed for Lantiq
55992bbd64eSDaniel Schwierzeck		XWAY SoCs for booting from NOR flash. The U-Boot image needs to
56092bbd64eSDaniel Schwierzeck		be swapped if a flash programmer is used.
56192bbd64eSDaniel Schwierzeck
562b67d8816SChristian Riesch- ARM options:
563b67d8816SChristian Riesch		CONFIG_SYS_EXCEPTION_VECTORS_HIGH
564b67d8816SChristian Riesch
565b67d8816SChristian Riesch		Select high exception vectors of the ARM core, e.g., do not
566b67d8816SChristian Riesch		clear the V bit of the c1 register of CP15.
567b67d8816SChristian Riesch
568207774b2SYork Sun		COUNTER_FREQUENCY
569207774b2SYork Sun		Generic timer clock source frequency.
570207774b2SYork Sun
571207774b2SYork Sun		COUNTER_FREQUENCY_REAL
572207774b2SYork Sun		Generic timer clock source frequency if the real clock is
573207774b2SYork Sun		different from COUNTER_FREQUENCY, and can only be determined
574207774b2SYork Sun		at run time.
575207774b2SYork Sun
57673c38934SStephen Warren- Tegra SoC options:
57773c38934SStephen Warren		CONFIG_TEGRA_SUPPORT_NON_SECURE
57873c38934SStephen Warren
57973c38934SStephen Warren		Support executing U-Boot in non-secure (NS) mode. Certain
58073c38934SStephen Warren		impossible actions will be skipped if the CPU is in NS mode,
58173c38934SStephen Warren		such as ARM architectural timer initialization.
58273c38934SStephen Warren
5835da627a4Swdenk- Linux Kernel Interface:
584c609719bSwdenk		CONFIG_CLOCKS_IN_MHZ
585c609719bSwdenk
586c609719bSwdenk		U-Boot stores all clock information in Hz
587c609719bSwdenk		internally. For binary compatibility with older Linux
588c609719bSwdenk		kernels (which expect the clocks passed in the
589c609719bSwdenk		bd_info data to be in MHz) the environment variable
590c609719bSwdenk		"clocks_in_mhz" can be defined so that U-Boot
591c609719bSwdenk		converts clock data to MHZ before passing it to the
592c609719bSwdenk		Linux kernel.
593c609719bSwdenk		When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
594c609719bSwdenk		"clocks_in_mhz=1" is automatically included in the
595c609719bSwdenk		default environment.
596c609719bSwdenk
5975da627a4Swdenk		CONFIG_MEMSIZE_IN_BYTES		[relevant for MIPS only]
5985da627a4Swdenk
599b445bbb4SJeremiah Mahler		When transferring memsize parameter to Linux, some versions
6005da627a4Swdenk		expect it to be in bytes, others in MB.
6015da627a4Swdenk		Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
6025da627a4Swdenk
603fec6d9eeSGerald Van Baren		CONFIG_OF_LIBFDT
604f57f70aaSWolfgang Denk
605f57f70aaSWolfgang Denk		New kernel versions are expecting firmware settings to be
606213bf8c8SGerald Van Baren		passed using flattened device trees (based on open firmware
607213bf8c8SGerald Van Baren		concepts).
608213bf8c8SGerald Van Baren
609213bf8c8SGerald Van Baren		CONFIG_OF_LIBFDT
610213bf8c8SGerald Van Baren		 * New libfdt-based support
611213bf8c8SGerald Van Baren		 * Adds the "fdt" command
6123bb342fcSKim Phillips		 * The bootm command automatically updates the fdt
613213bf8c8SGerald Van Baren
614f57f70aaSWolfgang Denk		OF_TBCLK - The timebase frequency.
615c2871f03SKumar Gala		OF_STDOUT_PATH - The path to the console device
616f57f70aaSWolfgang Denk
61711ccc33fSMarcel Ziswiler		boards with QUICC Engines require OF_QE to set UCC MAC
61811ccc33fSMarcel Ziswiler		addresses
6193bb342fcSKim Phillips
6204e253137SKumar Gala		CONFIG_OF_BOARD_SETUP
6214e253137SKumar Gala
6224e253137SKumar Gala		Board code has addition modification that it wants to make
6234e253137SKumar Gala		to the flat device tree before handing it off to the kernel
6246705d81eSwdenk
625c654b517SSimon Glass		CONFIG_OF_SYSTEM_SETUP
626c654b517SSimon Glass
627c654b517SSimon Glass		Other code has addition modification that it wants to make
628c654b517SSimon Glass		to the flat device tree before handing it off to the kernel.
629c654b517SSimon Glass		This causes ft_system_setup() to be called before booting
630c654b517SSimon Glass		the kernel.
631c654b517SSimon Glass
6323887c3fbSHeiko Schocher		CONFIG_OF_IDE_FIXUP
6333887c3fbSHeiko Schocher
6343887c3fbSHeiko Schocher		U-Boot can detect if an IDE device is present or not.
6353887c3fbSHeiko Schocher		If not, and this new config option is activated, U-Boot
6363887c3fbSHeiko Schocher		removes the ATA node from the DTS before booting Linux,
6373887c3fbSHeiko Schocher		so the Linux IDE driver does not probe the device and
6383887c3fbSHeiko Schocher		crash. This is needed for buggy hardware (uc101) where
6393887c3fbSHeiko Schocher		no pull down resistor is connected to the signal IDE5V_DD7.
6403887c3fbSHeiko Schocher
6417eb29398SIgor Grinberg		CONFIG_MACH_TYPE	[relevant for ARM only][mandatory]
6427eb29398SIgor Grinberg
6437eb29398SIgor Grinberg		This setting is mandatory for all boards that have only one
6447eb29398SIgor Grinberg		machine type and must be used to specify the machine type
6457eb29398SIgor Grinberg		number as it appears in the ARM machine registry
6467eb29398SIgor Grinberg		(see http://www.arm.linux.org.uk/developer/machines/).
6477eb29398SIgor Grinberg		Only boards that have multiple machine types supported
6487eb29398SIgor Grinberg		in a single configuration file and the machine type is
6497eb29398SIgor Grinberg		runtime discoverable, do not have to use this setting.
6507eb29398SIgor Grinberg
6510b2f4ecaSNiklaus Giger- vxWorks boot parameters:
6520b2f4ecaSNiklaus Giger
6530b2f4ecaSNiklaus Giger		bootvx constructs a valid bootline using the following
6549e98b7e3SBin Meng		environments variables: bootdev, bootfile, ipaddr, netmask,
6559e98b7e3SBin Meng		serverip, gatewayip, hostname, othbootargs.
6560b2f4ecaSNiklaus Giger		It loads the vxWorks image pointed bootfile.
6570b2f4ecaSNiklaus Giger
6580b2f4ecaSNiklaus Giger		Note: If a "bootargs" environment is defined, it will overwride
6590b2f4ecaSNiklaus Giger		the defaults discussed just above.
6600b2f4ecaSNiklaus Giger
6612c451f78SAneesh V- Cache Configuration:
6622c451f78SAneesh V		CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
6632c451f78SAneesh V		CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
6642c451f78SAneesh V		CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
6652c451f78SAneesh V
66693bc2193SAneesh V- Cache Configuration for ARM:
66793bc2193SAneesh V		CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
66893bc2193SAneesh V				      controller
66993bc2193SAneesh V		CONFIG_SYS_PL310_BASE - Physical base address of PL310
67093bc2193SAneesh V					controller register space
67193bc2193SAneesh V
6726705d81eSwdenk- Serial Ports:
67348d0192fSAndreas Engel		CONFIG_PL010_SERIAL
6746705d81eSwdenk
6756705d81eSwdenk		Define this if you want support for Amba PrimeCell PL010 UARTs.
6766705d81eSwdenk
67748d0192fSAndreas Engel		CONFIG_PL011_SERIAL
6786705d81eSwdenk
6796705d81eSwdenk		Define this if you want support for Amba PrimeCell PL011 UARTs.
6806705d81eSwdenk
6816705d81eSwdenk		CONFIG_PL011_CLOCK
6826705d81eSwdenk
6836705d81eSwdenk		If you have Amba PrimeCell PL011 UARTs, set this variable to
6846705d81eSwdenk		the clock speed of the UARTs.
6856705d81eSwdenk
6866705d81eSwdenk		CONFIG_PL01x_PORTS
6876705d81eSwdenk
6886705d81eSwdenk		If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
6896705d81eSwdenk		define this to a list of base addresses for each (supported)
6906705d81eSwdenk		port. See e.g. include/configs/versatile.h
6916705d81eSwdenk
692d57dee57SKaricheri, Muralidharan		CONFIG_SERIAL_HW_FLOW_CONTROL
693d57dee57SKaricheri, Muralidharan
694d57dee57SKaricheri, Muralidharan		Define this variable to enable hw flow control in serial driver.
695d57dee57SKaricheri, Muralidharan		Current user of this option is drivers/serial/nsl16550.c driver
6966705d81eSwdenk
697c609719bSwdenk- Console Baudrate:
698c609719bSwdenk		CONFIG_BAUDRATE - in bps
699c609719bSwdenk		Select one of the baudrates listed in
7006d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_BAUDRATE_TABLE, see below.
701c609719bSwdenk
702c609719bSwdenk- Autoboot Command:
703c609719bSwdenk		CONFIG_BOOTCOMMAND
704c609719bSwdenk		Only needed when CONFIG_BOOTDELAY is enabled;
705c609719bSwdenk		define a command string that is automatically executed
706c609719bSwdenk		when no character is read on the console interface
707c609719bSwdenk		within "Boot Delay" after reset.
708c609719bSwdenk
709c609719bSwdenk		CONFIG_RAMBOOT and CONFIG_NFSBOOT
710c609719bSwdenk		The value of these goes into the environment as
711c609719bSwdenk		"ramboot" and "nfsboot" respectively, and can be used
712c609719bSwdenk		as a convenience, when switching between booting from
71311ccc33fSMarcel Ziswiler		RAM and NFS.
714c609719bSwdenk
715eda0ba38SHeiko Schocher- Bootcount:
716eda0ba38SHeiko Schocher		CONFIG_BOOTCOUNT_LIMIT
717eda0ba38SHeiko Schocher		Implements a mechanism for detecting a repeating reboot
718eda0ba38SHeiko Schocher		cycle, see:
719eda0ba38SHeiko Schocher		http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
720eda0ba38SHeiko Schocher
721eda0ba38SHeiko Schocher		CONFIG_BOOTCOUNT_ENV
722eda0ba38SHeiko Schocher		If no softreset save registers are found on the hardware
723eda0ba38SHeiko Schocher		"bootcount" is stored in the environment. To prevent a
724eda0ba38SHeiko Schocher		saveenv on all reboots, the environment variable
725eda0ba38SHeiko Schocher		"upgrade_available" is used. If "upgrade_available" is
726eda0ba38SHeiko Schocher		0, "bootcount" is always 0, if "upgrade_available" is
727eda0ba38SHeiko Schocher		1 "bootcount" is incremented in the environment.
728eda0ba38SHeiko Schocher		So the Userspace Applikation must set the "upgrade_available"
729eda0ba38SHeiko Schocher		and "bootcount" variable to 0, if a boot was successfully.
730eda0ba38SHeiko Schocher
731c609719bSwdenk- Pre-Boot Commands:
732c609719bSwdenk		CONFIG_PREBOOT
733c609719bSwdenk
734c609719bSwdenk		When this option is #defined, the existence of the
735c609719bSwdenk		environment variable "preboot" will be checked
736c609719bSwdenk		immediately before starting the CONFIG_BOOTDELAY
737c609719bSwdenk		countdown and/or running the auto-boot command resp.
738c609719bSwdenk		entering interactive mode.
739c609719bSwdenk
740c609719bSwdenk		This feature is especially useful when "preboot" is
741c609719bSwdenk		automatically generated or modified. For an example
742c609719bSwdenk		see the LWMON board specific code: here "preboot" is
743c609719bSwdenk		modified when the user holds down a certain
744c609719bSwdenk		combination of keys on the (special) keyboard when
745c609719bSwdenk		booting the systems
746c609719bSwdenk
747c609719bSwdenk- Serial Download Echo Mode:
748c609719bSwdenk		CONFIG_LOADS_ECHO
749c609719bSwdenk		If defined to 1, all characters received during a
750c609719bSwdenk		serial download (using the "loads" command) are
751c609719bSwdenk		echoed back. This might be needed by some terminal
752c609719bSwdenk		emulations (like "cu"), but may as well just take
753c609719bSwdenk		time on others. This setting #define's the initial
754c609719bSwdenk		value of the "loads_echo" environment variable.
755c609719bSwdenk
756602ad3b3SJon Loeliger- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
757c609719bSwdenk		CONFIG_KGDB_BAUDRATE
758c609719bSwdenk		Select one of the baudrates listed in
7596d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_BAUDRATE_TABLE, see below.
760c609719bSwdenk
761302a6487SSimon Glass- Removal of commands
762302a6487SSimon Glass		If no commands are needed to boot, you can disable
763302a6487SSimon Glass		CONFIG_CMDLINE to remove them. In this case, the command line
764302a6487SSimon Glass		will not be available, and when U-Boot wants to execute the
765302a6487SSimon Glass		boot command (on start-up) it will call board_run_command()
766302a6487SSimon Glass		instead. This can reduce image size significantly for very
767302a6487SSimon Glass		simple boot procedures.
768302a6487SSimon Glass
769a5ecbe62SWolfgang Denk- Regular expression support:
770a5ecbe62SWolfgang Denk		CONFIG_REGEX
771a5ecbe62SWolfgang Denk		If this variable is defined, U-Boot is linked against
772a5ecbe62SWolfgang Denk		the SLRE (Super Light Regular Expression) library,
773a5ecbe62SWolfgang Denk		which adds regex support to some commands, as for
774a5ecbe62SWolfgang Denk		example "env grep" and "setexpr".
775a5ecbe62SWolfgang Denk
77645ba8077SSimon Glass- Device tree:
77745ba8077SSimon Glass		CONFIG_OF_CONTROL
77845ba8077SSimon Glass		If this variable is defined, U-Boot will use a device tree
77945ba8077SSimon Glass		to configure its devices, instead of relying on statically
78045ba8077SSimon Glass		compiled #defines in the board file. This option is
78145ba8077SSimon Glass		experimental and only available on a few boards. The device
78245ba8077SSimon Glass		tree is available in the global data as gd->fdt_blob.
78345ba8077SSimon Glass
7842c0f79e4SSimon Glass		U-Boot needs to get its device tree from somewhere. This can
78582f766d1SAlex Deymo		be done using one of the three options below:
786bbb0b128SSimon Glass
787bbb0b128SSimon Glass		CONFIG_OF_EMBED
788bbb0b128SSimon Glass		If this variable is defined, U-Boot will embed a device tree
789bbb0b128SSimon Glass		binary in its image. This device tree file should be in the
790bbb0b128SSimon Glass		board directory and called <soc>-<board>.dts. The binary file
791bbb0b128SSimon Glass		is then picked up in board_init_f() and made available through
792eb3eb602SNobuhiro Iwamatsu		the global data structure as gd->fdt_blob.
79345ba8077SSimon Glass
7942c0f79e4SSimon Glass		CONFIG_OF_SEPARATE
7952c0f79e4SSimon Glass		If this variable is defined, U-Boot will build a device tree
7962c0f79e4SSimon Glass		binary. It will be called u-boot.dtb. Architecture-specific
7972c0f79e4SSimon Glass		code will locate it at run-time. Generally this works by:
7982c0f79e4SSimon Glass
7992c0f79e4SSimon Glass			cat u-boot.bin u-boot.dtb >image.bin
8002c0f79e4SSimon Glass
8012c0f79e4SSimon Glass		and in fact, U-Boot does this for you, creating a file called
8022c0f79e4SSimon Glass		u-boot-dtb.bin which is useful in the common case. You can
8032c0f79e4SSimon Glass		still use the individual files if you need something more
8042c0f79e4SSimon Glass		exotic.
8052c0f79e4SSimon Glass
80682f766d1SAlex Deymo		CONFIG_OF_BOARD
80782f766d1SAlex Deymo		If this variable is defined, U-Boot will use the device tree
80882f766d1SAlex Deymo		provided by the board at runtime instead of embedding one with
80982f766d1SAlex Deymo		the image. Only boards defining board_fdt_blob_setup() support
81082f766d1SAlex Deymo		this option (see include/fdtdec.h file).
81182f766d1SAlex Deymo
812c609719bSwdenk- Watchdog:
813c609719bSwdenk		CONFIG_WATCHDOG
814c609719bSwdenk		If this variable is defined, it enables watchdog
8156abe6fb6SDetlev Zundel		support for the SoC. There must be support in the SoC
816907208c4SChristophe Leroy		specific code for a watchdog. For the 8xx
817907208c4SChristophe Leroy		CPUs, the SIU Watchdog feature is enabled in the SYPCR
818907208c4SChristophe Leroy		register.  When supported for a specific SoC is
819907208c4SChristophe Leroy		available, then no further board specific code should
820907208c4SChristophe Leroy		be needed to use it.
8216abe6fb6SDetlev Zundel
8226abe6fb6SDetlev Zundel		CONFIG_HW_WATCHDOG
8236abe6fb6SDetlev Zundel		When using a watchdog circuitry external to the used
8246abe6fb6SDetlev Zundel		SoC, then define this variable and provide board
8256abe6fb6SDetlev Zundel		specific code for the "hw_watchdog_reset" function.
826c609719bSwdenk
8277bae0d6fSHeiko Schocher		CONFIG_AT91_HW_WDT_TIMEOUT
8287bae0d6fSHeiko Schocher		specify the timeout in seconds. default 2 seconds.
8297bae0d6fSHeiko Schocher
830c1551ea8Sstroese- U-Boot Version:
831c1551ea8Sstroese		CONFIG_VERSION_VARIABLE
832c1551ea8Sstroese		If this variable is defined, an environment variable
833c1551ea8Sstroese		named "ver" is created by U-Boot showing the U-Boot
834c1551ea8Sstroese		version as printed by the "version" command.
835a1ea8e51SBenoît Thébaudeau		Any change to this variable will be reverted at the
836a1ea8e51SBenoît Thébaudeau		next reset.
837c1551ea8Sstroese
838c609719bSwdenk- Real-Time Clock:
839c609719bSwdenk
840602ad3b3SJon Loeliger		When CONFIG_CMD_DATE is selected, the type of the RTC
841c609719bSwdenk		has to be selected, too. Define exactly one of the
842c609719bSwdenk		following options:
843c609719bSwdenk
844c609719bSwdenk		CONFIG_RTC_PCF8563	- use Philips PCF8563 RTC
8454e8b7544SFabio Estevam		CONFIG_RTC_MC13XXX	- use MC13783 or MC13892 RTC
846c609719bSwdenk		CONFIG_RTC_MC146818	- use MC146818 RTC
8471cb8e980Swdenk		CONFIG_RTC_DS1307	- use Maxim, Inc. DS1307 RTC
848c609719bSwdenk		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC
8497f70e853Swdenk		CONFIG_RTC_DS1338	- use Maxim, Inc. DS1338 RTC
850412921d2SMarkus Niebel		CONFIG_RTC_DS1339	- use Maxim, Inc. DS1339 RTC
8513bac3513Swdenk		CONFIG_RTC_DS164x	- use Dallas DS164x RTC
8529536dfccSTor Krill		CONFIG_RTC_ISL1208	- use Intersil ISL1208 RTC
8534c0d4c3bSwdenk		CONFIG_RTC_MAX6900	- use Maxim, Inc. MAX6900 RTC
8542bd3cab3SChris Packham		CONFIG_RTC_DS1337_NOOSC	- Turn off the OSC output for DS1337
85571d19f30SHeiko Schocher		CONFIG_SYS_RV3029_TCR	- enable trickle charger on
85671d19f30SHeiko Schocher					  RV3029 RTC.
857c609719bSwdenk
858b37c7e5eSwdenk		Note that if the RTC uses I2C, then the I2C interface
859b37c7e5eSwdenk		must also be configured. See I2C Support, below.
860b37c7e5eSwdenk
861e92739d3SPeter Tyser- GPIO Support:
862e92739d3SPeter Tyser		CONFIG_PCA953X		- use NXP's PCA953X series I2C GPIO
863e92739d3SPeter Tyser
8645dec49caSChris Packham		The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
8655dec49caSChris Packham		chip-ngpio pairs that tell the PCA953X driver the number of
8665dec49caSChris Packham		pins supported by a particular chip.
8675dec49caSChris Packham
868e92739d3SPeter Tyser		Note that if the GPIO device uses I2C, then the I2C interface
869e92739d3SPeter Tyser		must also be configured. See I2C Support, below.
870e92739d3SPeter Tyser
871aa53233aSSimon Glass- I/O tracing:
872aa53233aSSimon Glass		When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
873aa53233aSSimon Glass		accesses and can checksum them or write a list of them out
874aa53233aSSimon Glass		to memory. See the 'iotrace' command for details. This is
875aa53233aSSimon Glass		useful for testing device drivers since it can confirm that
876aa53233aSSimon Glass		the driver behaves the same way before and after a code
877aa53233aSSimon Glass		change. Currently this is supported on sandbox and arm. To
878aa53233aSSimon Glass		add support for your architecture, add '#include <iotrace.h>'
879aa53233aSSimon Glass		to the bottom of arch/<arch>/include/asm/io.h and test.
880aa53233aSSimon Glass
881aa53233aSSimon Glass		Example output from the 'iotrace stats' command is below.
882aa53233aSSimon Glass		Note that if the trace buffer is exhausted, the checksum will
883aa53233aSSimon Glass		still continue to operate.
884aa53233aSSimon Glass
885aa53233aSSimon Glass			iotrace is enabled
886aa53233aSSimon Glass			Start:  10000000	(buffer start address)
887aa53233aSSimon Glass			Size:   00010000	(buffer size)
888aa53233aSSimon Glass			Offset: 00000120	(current buffer offset)
889aa53233aSSimon Glass			Output: 10000120	(start + offset)
890aa53233aSSimon Glass			Count:  00000018	(number of trace records)
891aa53233aSSimon Glass			CRC32:  9526fb66	(CRC32 of all trace records)
892aa53233aSSimon Glass
893c609719bSwdenk- Timestamp Support:
894c609719bSwdenk
895c609719bSwdenk		When CONFIG_TIMESTAMP is selected, the timestamp
896c609719bSwdenk		(date and time) of an image is printed by image
897c609719bSwdenk		commands like bootm or iminfo. This option is
898602ad3b3SJon Loeliger		automatically enabled when you select CONFIG_CMD_DATE .
899c609719bSwdenk
900923c46f9SKarl O. Pinc- Partition Labels (disklabels) Supported:
901923c46f9SKarl O. Pinc		Zero or more of the following:
902923c46f9SKarl O. Pinc		CONFIG_MAC_PARTITION   Apple's MacOS partition table.
903923c46f9SKarl O. Pinc		CONFIG_ISO_PARTITION   ISO partition table, used on CDROM etc.
904923c46f9SKarl O. Pinc		CONFIG_EFI_PARTITION   GPT partition table, common when EFI is the
905923c46f9SKarl O. Pinc				       bootloader.  Note 2TB partition limit; see
906923c46f9SKarl O. Pinc				       disk/part_efi.c
907923c46f9SKarl O. Pinc		CONFIG_MTD_PARTITIONS  Memory Technology Device partition table.
908c609719bSwdenk
909fc843a02SSimon Glass		If IDE or SCSI support is enabled (CONFIG_IDE or
910c649e3c9SSimon Glass		CONFIG_SCSI) you must configure support for at
911923c46f9SKarl O. Pinc		least one non-MTD partition type as well.
912c609719bSwdenk
913c609719bSwdenk- IDE Reset method:
9144d13cbadSwdenk		CONFIG_IDE_RESET_ROUTINE - this is defined in several
9154d13cbadSwdenk		board configurations files but used nowhere!
916c609719bSwdenk
9174d13cbadSwdenk		CONFIG_IDE_RESET - is this is defined, IDE Reset will
9184d13cbadSwdenk		be performed by calling the function
9194d13cbadSwdenk			ide_set_reset(int reset)
9204d13cbadSwdenk		which has to be defined in a board specific file
921c609719bSwdenk
922c609719bSwdenk- ATAPI Support:
923c609719bSwdenk		CONFIG_ATAPI
924c609719bSwdenk
925c609719bSwdenk		Set this to enable ATAPI support.
926c609719bSwdenk
927c40b2956Swdenk- LBA48 Support
928c40b2956Swdenk		CONFIG_LBA48
929c40b2956Swdenk
930c40b2956Swdenk		Set this to enable support for disks larger than 137GB
9314b142febSHeiko Schocher		Also look at CONFIG_SYS_64BIT_LBA.
932c40b2956Swdenk		Whithout these , LBA48 support uses 32bit variables and will 'only'
933c40b2956Swdenk		support disks up to 2.1TB.
934c40b2956Swdenk
9356d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_64BIT_LBA:
936c40b2956Swdenk			When enabled, makes the IDE subsystem use 64bit sector addresses.
937c40b2956Swdenk			Default is 32bit.
938c40b2956Swdenk
939c609719bSwdenk- SCSI Support:
9406d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
9416d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
9426d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
943c609719bSwdenk		maximum numbers of LUNs, SCSI ID's and target
944c609719bSwdenk		devices.
945c609719bSwdenk
946447c031bSStefan Reinauer		The environment variable 'scsidevs' is set to the number of
947447c031bSStefan Reinauer		SCSI devices found during the last scan.
948447c031bSStefan Reinauer
949c609719bSwdenk- NETWORK Support (PCI):
950682011ffSwdenk		CONFIG_E1000
951ce5207e1SKyle Moffett		Support for Intel 8254x/8257x gigabit chips.
952ce5207e1SKyle Moffett
953ce5207e1SKyle Moffett		CONFIG_E1000_SPI
954ce5207e1SKyle Moffett		Utility code for direct access to the SPI bus on Intel 8257x.
955ce5207e1SKyle Moffett		This does not do anything useful unless you set at least one
956ce5207e1SKyle Moffett		of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
957ce5207e1SKyle Moffett
958ce5207e1SKyle Moffett		CONFIG_E1000_SPI_GENERIC
959ce5207e1SKyle Moffett		Allow generic access to the SPI bus on the Intel 8257x, for
960ce5207e1SKyle Moffett		example with the "sspi" command.
961ce5207e1SKyle Moffett
962c609719bSwdenk		CONFIG_EEPRO100
963c609719bSwdenk		Support for Intel 82557/82559/82559ER chips.
96411ccc33fSMarcel Ziswiler		Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
965c609719bSwdenk		write routine for first time initialisation.
966c609719bSwdenk
967c609719bSwdenk		CONFIG_TULIP
968c609719bSwdenk		Support for Digital 2114x chips.
969c609719bSwdenk		Optional CONFIG_TULIP_SELECT_MEDIA for board specific
970c609719bSwdenk		modem chip initialisation (KS8761/QS6611).
971c609719bSwdenk
972c609719bSwdenk		CONFIG_NATSEMI
973c609719bSwdenk		Support for National dp83815 chips.
974c609719bSwdenk
975c609719bSwdenk		CONFIG_NS8382X
976c609719bSwdenk		Support for National dp8382[01] gigabit chips.
977c609719bSwdenk
97845219c46Swdenk- NETWORK Support (other):
97945219c46Swdenk
980c041e9d2SJens Scharsig		CONFIG_DRIVER_AT91EMAC
981c041e9d2SJens Scharsig		Support for AT91RM9200 EMAC.
982c041e9d2SJens Scharsig
983c041e9d2SJens Scharsig			CONFIG_RMII
984c041e9d2SJens Scharsig			Define this to use reduced MII inteface
985c041e9d2SJens Scharsig
986c041e9d2SJens Scharsig			CONFIG_DRIVER_AT91EMAC_QUIET
987c041e9d2SJens Scharsig			If this defined, the driver is quiet.
988c041e9d2SJens Scharsig			The driver doen't show link status messages.
989c041e9d2SJens Scharsig
990efdd7319SRob Herring		CONFIG_CALXEDA_XGMAC
991efdd7319SRob Herring		Support for the Calxeda XGMAC device
992efdd7319SRob Herring
9933bb46d23SAshok		CONFIG_LAN91C96
99445219c46Swdenk		Support for SMSC's LAN91C96 chips.
99545219c46Swdenk
99645219c46Swdenk			CONFIG_LAN91C96_USE_32_BIT
99745219c46Swdenk			Define this to enable 32 bit addressing
99845219c46Swdenk
9993bb46d23SAshok		CONFIG_SMC91111
1000f39748aeSwdenk		Support for SMSC's LAN91C111 chip
1001f39748aeSwdenk
1002f39748aeSwdenk			CONFIG_SMC91111_BASE
1003f39748aeSwdenk			Define this to hold the physical address
1004f39748aeSwdenk			of the device (I/O space)
1005f39748aeSwdenk
1006f39748aeSwdenk			CONFIG_SMC_USE_32_BIT
1007f39748aeSwdenk			Define this if data bus is 32 bits
1008f39748aeSwdenk
1009f39748aeSwdenk			CONFIG_SMC_USE_IOFUNCS
1010f39748aeSwdenk			Define this to use i/o functions instead of macros
1011f39748aeSwdenk			(some hardware wont work with macros)
1012f39748aeSwdenk
1013dc02badaSHeiko Schocher		CONFIG_DRIVER_TI_EMAC
1014dc02badaSHeiko Schocher		Support for davinci emac
1015dc02badaSHeiko Schocher
1016dc02badaSHeiko Schocher			CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1017dc02badaSHeiko Schocher			Define this if you have more then 3 PHYs.
1018dc02badaSHeiko Schocher
1019b3dbf4a5SMacpaul Lin		CONFIG_FTGMAC100
1020b3dbf4a5SMacpaul Lin		Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1021b3dbf4a5SMacpaul Lin
1022b3dbf4a5SMacpaul Lin			CONFIG_FTGMAC100_EGIGA
1023b3dbf4a5SMacpaul Lin			Define this to use GE link update with gigabit PHY.
1024b3dbf4a5SMacpaul Lin			Define this if FTGMAC100 is connected to gigabit PHY.
1025b3dbf4a5SMacpaul Lin			If your system has 10/100 PHY only, it might not occur
1026b3dbf4a5SMacpaul Lin			wrong behavior. Because PHY usually return timeout or
1027b3dbf4a5SMacpaul Lin			useless data when polling gigabit status and gigabit
1028b3dbf4a5SMacpaul Lin			control registers. This behavior won't affect the
1029b3dbf4a5SMacpaul Lin			correctnessof 10/100 link speed update.
1030b3dbf4a5SMacpaul Lin
1031c2fff331SMike Rapoport		CONFIG_SMC911X
1032557b377dSJens Gehrlein		Support for SMSC's LAN911x and LAN921x chips
1033557b377dSJens Gehrlein
1034c2fff331SMike Rapoport			CONFIG_SMC911X_BASE
1035557b377dSJens Gehrlein			Define this to hold the physical address
1036557b377dSJens Gehrlein			of the device (I/O space)
1037557b377dSJens Gehrlein
1038c2fff331SMike Rapoport			CONFIG_SMC911X_32_BIT
1039557b377dSJens Gehrlein			Define this if data bus is 32 bits
1040557b377dSJens Gehrlein
1041c2fff331SMike Rapoport			CONFIG_SMC911X_16_BIT
1042557b377dSJens Gehrlein			Define this if data bus is 16 bits. If your processor
1043557b377dSJens Gehrlein			automatically converts one 32 bit word to two 16 bit
1044c2fff331SMike Rapoport			words you may also try CONFIG_SMC911X_32_BIT.
1045557b377dSJens Gehrlein
10463d0075faSYoshihiro Shimoda		CONFIG_SH_ETHER
10473d0075faSYoshihiro Shimoda		Support for Renesas on-chip Ethernet controller
10483d0075faSYoshihiro Shimoda
10493d0075faSYoshihiro Shimoda			CONFIG_SH_ETHER_USE_PORT
10503d0075faSYoshihiro Shimoda			Define the number of ports to be used
10513d0075faSYoshihiro Shimoda
10523d0075faSYoshihiro Shimoda			CONFIG_SH_ETHER_PHY_ADDR
10533d0075faSYoshihiro Shimoda			Define the ETH PHY's address
10543d0075faSYoshihiro Shimoda
105568260aabSYoshihiro Shimoda			CONFIG_SH_ETHER_CACHE_WRITEBACK
105668260aabSYoshihiro Shimoda			If this option is set, the driver enables cache flush.
105768260aabSYoshihiro Shimoda
1058b2f97cf2SHeiko Schocher- PWM Support:
1059b2f97cf2SHeiko Schocher		CONFIG_PWM_IMX
10605052e819SRobert P. J. Day		Support for PWM module on the imx6.
1061b2f97cf2SHeiko Schocher
10625e124724SVadim Bendebury- TPM Support:
106390899cc0SChe-liang Chiou		CONFIG_TPM
106490899cc0SChe-liang Chiou		Support TPM devices.
106590899cc0SChe-liang Chiou
10660766ad2fSChristophe Ricard		CONFIG_TPM_TIS_INFINEON
10670766ad2fSChristophe Ricard		Support for Infineon i2c bus TPM devices. Only one device
10681b393db5STom Wai-Hong Tam		per system is supported at this time.
10691b393db5STom Wai-Hong Tam
10701b393db5STom Wai-Hong Tam			CONFIG_TPM_TIS_I2C_BURST_LIMITATION
10711b393db5STom Wai-Hong Tam			Define the burst count bytes upper limit
10721b393db5STom Wai-Hong Tam
10733aa74088SChristophe Ricard		CONFIG_TPM_ST33ZP24
10743aa74088SChristophe Ricard		Support for STMicroelectronics TPM devices. Requires DM_TPM support.
10753aa74088SChristophe Ricard
10763aa74088SChristophe Ricard			CONFIG_TPM_ST33ZP24_I2C
10773aa74088SChristophe Ricard			Support for STMicroelectronics ST33ZP24 I2C devices.
10783aa74088SChristophe Ricard			Requires TPM_ST33ZP24 and I2C.
10793aa74088SChristophe Ricard
1080b75fdc11SChristophe Ricard			CONFIG_TPM_ST33ZP24_SPI
1081b75fdc11SChristophe Ricard			Support for STMicroelectronics ST33ZP24 SPI devices.
1082b75fdc11SChristophe Ricard			Requires TPM_ST33ZP24 and SPI.
1083b75fdc11SChristophe Ricard
1084c01939c7SDirk Eibach		CONFIG_TPM_ATMEL_TWI
1085c01939c7SDirk Eibach		Support for Atmel TWI TPM device. Requires I2C support.
1086c01939c7SDirk Eibach
108790899cc0SChe-liang Chiou		CONFIG_TPM_TIS_LPC
10885e124724SVadim Bendebury		Support for generic parallel port TPM devices. Only one device
10895e124724SVadim Bendebury		per system is supported at this time.
10905e124724SVadim Bendebury
10915e124724SVadim Bendebury			CONFIG_TPM_TIS_BASE_ADDRESS
10925e124724SVadim Bendebury			Base address where the generic TPM device is mapped
10935e124724SVadim Bendebury			to. Contemporary x86 systems usually map it at
10945e124724SVadim Bendebury			0xfed40000.
10955e124724SVadim Bendebury
1096be6c1529SReinhard Pfau		CONFIG_TPM
1097be6c1529SReinhard Pfau		Define this to enable the TPM support library which provides
1098be6c1529SReinhard Pfau		functional interfaces to some TPM commands.
1099be6c1529SReinhard Pfau		Requires support for a TPM device.
1100be6c1529SReinhard Pfau
1101be6c1529SReinhard Pfau		CONFIG_TPM_AUTH_SESSIONS
1102be6c1529SReinhard Pfau		Define this to enable authorized functions in the TPM library.
1103be6c1529SReinhard Pfau		Requires CONFIG_TPM and CONFIG_SHA1.
1104be6c1529SReinhard Pfau
1105c609719bSwdenk- USB Support:
1106c609719bSwdenk		At the moment only the UHCI host controller is
1107064b55cfSHeiko Schocher		supported (PIP405, MIP405); define
1108c609719bSwdenk		CONFIG_USB_UHCI to enable it.
1109c609719bSwdenk		define CONFIG_USB_KEYBOARD to enable the USB Keyboard
111030d56faeSwdenk		and define CONFIG_USB_STORAGE to enable the USB
1111c609719bSwdenk		storage devices.
1112c609719bSwdenk		Note:
1113c609719bSwdenk		Supported are USB Keyboards and USB Floppy drives
1114c609719bSwdenk		(TEAC FD-05PUB).
11154d13cbadSwdenk
11169ab4ce22SSimon Glass		CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
11179ab4ce22SSimon Glass		txfilltuning field in the EHCI controller on reset.
11189ab4ce22SSimon Glass
11196e9e0626SOleksandr Tymoshenko		CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
11206e9e0626SOleksandr Tymoshenko		HW module registers.
11216e9e0626SOleksandr Tymoshenko
112216c8d5e7SWolfgang Denk- USB Device:
112316c8d5e7SWolfgang Denk		Define the below if you wish to use the USB console.
112416c8d5e7SWolfgang Denk		Once firmware is rebuilt from a serial console issue the
112516c8d5e7SWolfgang Denk		command "setenv stdin usbtty; setenv stdout usbtty" and
112611ccc33fSMarcel Ziswiler		attach your USB cable. The Unix command "dmesg" should print
112716c8d5e7SWolfgang Denk		it has found a new device. The environment variable usbtty
112816c8d5e7SWolfgang Denk		can be set to gserial or cdc_acm to enable your device to
112916c8d5e7SWolfgang Denk		appear to a USB host as a Linux gserial device or a
113016c8d5e7SWolfgang Denk		Common Device Class Abstract Control Model serial device.
113116c8d5e7SWolfgang Denk		If you select usbtty = gserial you should be able to enumerate
113216c8d5e7SWolfgang Denk		a Linux host by
113316c8d5e7SWolfgang Denk		# modprobe usbserial vendor=0xVendorID product=0xProductID
113416c8d5e7SWolfgang Denk		else if using cdc_acm, simply setting the environment
113516c8d5e7SWolfgang Denk		variable usbtty to be cdc_acm should suffice. The following
113616c8d5e7SWolfgang Denk		might be defined in YourBoardName.h
113716c8d5e7SWolfgang Denk
113816c8d5e7SWolfgang Denk			CONFIG_USB_DEVICE
113916c8d5e7SWolfgang Denk			Define this to build a UDC device
114016c8d5e7SWolfgang Denk
114116c8d5e7SWolfgang Denk			CONFIG_USB_TTY
114216c8d5e7SWolfgang Denk			Define this to have a tty type of device available to
114316c8d5e7SWolfgang Denk			talk to the UDC device
114416c8d5e7SWolfgang Denk
1145f9da0f89SVipin KUMAR			CONFIG_USBD_HS
1146f9da0f89SVipin KUMAR			Define this to enable the high speed support for usb
1147f9da0f89SVipin KUMAR			device and usbtty. If this feature is enabled, a routine
1148f9da0f89SVipin KUMAR			int is_usbd_high_speed(void)
1149f9da0f89SVipin KUMAR			also needs to be defined by the driver to dynamically poll
1150f9da0f89SVipin KUMAR			whether the enumeration has succeded at high speed or full
1151f9da0f89SVipin KUMAR			speed.
1152f9da0f89SVipin KUMAR
11536d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_CONSOLE_IS_IN_ENV
115416c8d5e7SWolfgang Denk			Define this if you want stdin, stdout &/or stderr to
115516c8d5e7SWolfgang Denk			be set to usbtty.
115616c8d5e7SWolfgang Denk
115716c8d5e7SWolfgang Denk		If you have a USB-IF assigned VendorID then you may wish to
115816c8d5e7SWolfgang Denk		define your own vendor specific values either in BoardName.h
115916c8d5e7SWolfgang Denk		or directly in usbd_vendor_info.h. If you don't define
116016c8d5e7SWolfgang Denk		CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
116116c8d5e7SWolfgang Denk		CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
116216c8d5e7SWolfgang Denk		should pretend to be a Linux device to it's target host.
116316c8d5e7SWolfgang Denk
116416c8d5e7SWolfgang Denk			CONFIG_USBD_MANUFACTURER
116516c8d5e7SWolfgang Denk			Define this string as the name of your company for
116616c8d5e7SWolfgang Denk			- CONFIG_USBD_MANUFACTURER "my company"
116716c8d5e7SWolfgang Denk
116816c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCT_NAME
116916c8d5e7SWolfgang Denk			Define this string as the name of your product
117016c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCT_NAME "acme usb device"
117116c8d5e7SWolfgang Denk
117216c8d5e7SWolfgang Denk			CONFIG_USBD_VENDORID
117316c8d5e7SWolfgang Denk			Define this as your assigned Vendor ID from the USB
117416c8d5e7SWolfgang Denk			Implementors Forum. This *must* be a genuine Vendor ID
117516c8d5e7SWolfgang Denk			to avoid polluting the USB namespace.
117616c8d5e7SWolfgang Denk			- CONFIG_USBD_VENDORID 0xFFFF
117716c8d5e7SWolfgang Denk
117816c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCTID
117916c8d5e7SWolfgang Denk			Define this as the unique Product ID
118016c8d5e7SWolfgang Denk			for your device
118116c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCTID 0xFFFF
1182c609719bSwdenk
1183d70a560fSIgor Grinberg- ULPI Layer Support:
1184d70a560fSIgor Grinberg		The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1185d70a560fSIgor Grinberg		the generic ULPI layer. The generic layer accesses the ULPI PHY
1186d70a560fSIgor Grinberg		via the platform viewport, so you need both the genric layer and
1187d70a560fSIgor Grinberg		the viewport enabled. Currently only Chipidea/ARC based
1188d70a560fSIgor Grinberg		viewport is supported.
1189d70a560fSIgor Grinberg		To enable the ULPI layer support, define CONFIG_USB_ULPI and
1190d70a560fSIgor Grinberg		CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
11916d365ea0SLucas Stach		If your ULPI phy needs a different reference clock than the
11926d365ea0SLucas Stach		standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
11936d365ea0SLucas Stach		the appropriate value in Hz.
1194c609719bSwdenk
1195c609719bSwdenk- MMC Support:
1196c609719bSwdenk		The MMC controller on the Intel PXA is supported. To
1197c609719bSwdenk		enable this define CONFIG_MMC. The MMC can be
1198c609719bSwdenk		accessed from the boot prompt by mapping the device
1199c609719bSwdenk		to physical memory similar to flash. Command line is
1200602ad3b3SJon Loeliger		enabled with CONFIG_CMD_MMC. The MMC driver also works with
1201602ad3b3SJon Loeliger		the FAT fs. This is enabled with CONFIG_CMD_FAT.
1202c609719bSwdenk
1203afb35666SYoshihiro Shimoda		CONFIG_SH_MMCIF
1204afb35666SYoshihiro Shimoda		Support for Renesas on-chip MMCIF controller
1205afb35666SYoshihiro Shimoda
1206afb35666SYoshihiro Shimoda			CONFIG_SH_MMCIF_ADDR
1207afb35666SYoshihiro Shimoda			Define the base address of MMCIF registers
1208afb35666SYoshihiro Shimoda
1209afb35666SYoshihiro Shimoda			CONFIG_SH_MMCIF_CLK
1210afb35666SYoshihiro Shimoda			Define the clock frequency for MMCIF
1211afb35666SYoshihiro Shimoda
12121fd93c6eSPierre Aubert		CONFIG_SUPPORT_EMMC_BOOT
12131fd93c6eSPierre Aubert		Enable some additional features of the eMMC boot partitions.
12141fd93c6eSPierre Aubert
12151fd93c6eSPierre Aubert		CONFIG_SUPPORT_EMMC_RPMB
12161fd93c6eSPierre Aubert		Enable the commands for reading, writing and programming the
12171fd93c6eSPierre Aubert		key for the Replay Protection Memory Block partition in eMMC.
12181fd93c6eSPierre Aubert
1219b3ba6e94STom Rini- USB Device Firmware Update (DFU) class support:
122001acd6abSPaul Kocialkowski		CONFIG_USB_FUNCTION_DFU
1221b3ba6e94STom Rini		This enables the USB portion of the DFU USB class
1222b3ba6e94STom Rini
1223b3ba6e94STom Rini		CONFIG_DFU_MMC
1224b3ba6e94STom Rini		This enables support for exposing (e)MMC devices via DFU.
1225b3ba6e94STom Rini
1226c6631764SPantelis Antoniou		CONFIG_DFU_NAND
1227c6631764SPantelis Antoniou		This enables support for exposing NAND devices via DFU.
1228c6631764SPantelis Antoniou
1229a9479f04SAfzal Mohammed		CONFIG_DFU_RAM
1230a9479f04SAfzal Mohammed		This enables support for exposing RAM via DFU.
1231a9479f04SAfzal Mohammed		Note: DFU spec refer to non-volatile memory usage, but
1232a9479f04SAfzal Mohammed		allow usages beyond the scope of spec - here RAM usage,
1233a9479f04SAfzal Mohammed		one that would help mostly the developer.
1234a9479f04SAfzal Mohammed
1235e7e75c70SHeiko Schocher		CONFIG_SYS_DFU_DATA_BUF_SIZE
1236e7e75c70SHeiko Schocher		Dfu transfer uses a buffer before writing data to the
1237e7e75c70SHeiko Schocher		raw storage device. Make the size (in bytes) of this buffer
1238e7e75c70SHeiko Schocher		configurable. The size of this buffer is also configurable
1239e7e75c70SHeiko Schocher		through the "dfu_bufsiz" environment variable.
1240e7e75c70SHeiko Schocher
1241ea2453d5SPantelis Antoniou		CONFIG_SYS_DFU_MAX_FILE_SIZE
1242ea2453d5SPantelis Antoniou		When updating files rather than the raw storage device,
1243ea2453d5SPantelis Antoniou		we use a static buffer to copy the file into and then write
1244ea2453d5SPantelis Antoniou		the buffer once we've been given the whole file.  Define
1245ea2453d5SPantelis Antoniou		this to the maximum filesize (in bytes) for the buffer.
1246ea2453d5SPantelis Antoniou		Default is 4 MiB if undefined.
1247ea2453d5SPantelis Antoniou
1248001a8319SHeiko Schocher		DFU_DEFAULT_POLL_TIMEOUT
1249001a8319SHeiko Schocher		Poll timeout [ms], is the timeout a device can send to the
1250001a8319SHeiko Schocher		host. The host must wait for this timeout before sending
1251001a8319SHeiko Schocher		a subsequent DFU_GET_STATUS request to the device.
1252001a8319SHeiko Schocher
1253001a8319SHeiko Schocher		DFU_MANIFEST_POLL_TIMEOUT
1254001a8319SHeiko Schocher		Poll timeout [ms], which the device sends to the host when
1255001a8319SHeiko Schocher		entering dfuMANIFEST state. Host waits this timeout, before
1256001a8319SHeiko Schocher		sending again an USB request to the device.
1257001a8319SHeiko Schocher
12586705d81eSwdenk- Journaling Flash filesystem support:
1259b2482dffSSimon Glass		CONFIG_JFFS2_NAND
12606705d81eSwdenk		Define these for a default partition on a NAND device
12616705d81eSwdenk
12626d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_JFFS2_FIRST_SECTOR,
12636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
12646705d81eSwdenk		Define these for a default partition on a NOR device
12656705d81eSwdenk
1266c609719bSwdenk- Keyboard Support:
126739f615edSSimon Glass		See Kconfig help for available keyboard drivers.
126839f615edSSimon Glass
126939f615edSSimon Glass		CONFIG_KEYBOARD
127039f615edSSimon Glass
127139f615edSSimon Glass		Define this to enable a custom keyboard support.
127239f615edSSimon Glass		This simply calls drv_keyboard_init() which must be
127339f615edSSimon Glass		defined in your board-specific files. This option is deprecated
127439f615edSSimon Glass		and is only used by novena. For new boards, use driver model
127539f615edSSimon Glass		instead.
1276c609719bSwdenk
1277c609719bSwdenk- Video support:
12787d3053fbSTimur Tabi		CONFIG_FSL_DIU_FB
12797d3053fbSTimur Tabi		Enable the Freescale DIU video driver.	Reference boards for
12807d3053fbSTimur Tabi		SOCs that have a DIU should define this macro to enable DIU
12817d3053fbSTimur Tabi		support, and should also define these other macros:
12827d3053fbSTimur Tabi
12837d3053fbSTimur Tabi			CONFIG_SYS_DIU_ADDR
12847d3053fbSTimur Tabi			CONFIG_VIDEO
12857d3053fbSTimur Tabi			CONFIG_CFB_CONSOLE
12867d3053fbSTimur Tabi			CONFIG_VIDEO_SW_CURSOR
12877d3053fbSTimur Tabi			CONFIG_VGA_AS_SINGLE_DEVICE
12887d3053fbSTimur Tabi			CONFIG_VIDEO_LOGO
12897d3053fbSTimur Tabi			CONFIG_VIDEO_BMP_LOGO
12907d3053fbSTimur Tabi
1291ba8e76bdSTimur Tabi		The DIU driver will look for the 'video-mode' environment
1292ba8e76bdSTimur Tabi		variable, and if defined, enable the DIU as a console during
12938eca9439SFabio Estevam		boot.  See the documentation file doc/README.video for a
1294ba8e76bdSTimur Tabi		description of this variable.
12957d3053fbSTimur Tabi
1296c609719bSwdenk- LCD Support:	CONFIG_LCD
1297c609719bSwdenk
1298c609719bSwdenk		Define this to enable LCD support (for output to LCD
1299c609719bSwdenk		display); also select one of the supported displays
1300c609719bSwdenk		by defining one of these:
1301c609719bSwdenk
130239cf4804SStelian Pop		CONFIG_ATMEL_LCD:
130339cf4804SStelian Pop
130439cf4804SStelian Pop			HITACHI TX09D70VM1CCA, 3.5", 240x320.
130539cf4804SStelian Pop
1306fd3103bbSwdenk		CONFIG_NEC_NL6448AC33:
1307c609719bSwdenk
1308fd3103bbSwdenk			NEC NL6448AC33-18. Active, color, single scan.
1309c609719bSwdenk
1310fd3103bbSwdenk		CONFIG_NEC_NL6448BC20
1311c609719bSwdenk
1312fd3103bbSwdenk			NEC NL6448BC20-08. 6.5", 640x480.
1313fd3103bbSwdenk			Active, color, single scan.
1314fd3103bbSwdenk
1315fd3103bbSwdenk		CONFIG_NEC_NL6448BC33_54
1316fd3103bbSwdenk
1317fd3103bbSwdenk			NEC NL6448BC33-54. 10.4", 640x480.
1318c609719bSwdenk			Active, color, single scan.
1319c609719bSwdenk
1320c609719bSwdenk		CONFIG_SHARP_16x9
1321c609719bSwdenk
1322c609719bSwdenk			Sharp 320x240. Active, color, single scan.
1323c609719bSwdenk			It isn't 16x9, and I am not sure what it is.
1324c609719bSwdenk
1325c609719bSwdenk		CONFIG_SHARP_LQ64D341
1326c609719bSwdenk
1327c609719bSwdenk			Sharp LQ64D341 display, 640x480.
1328c609719bSwdenk			Active, color, single scan.
1329c609719bSwdenk
1330c609719bSwdenk		CONFIG_HLD1045
1331c609719bSwdenk
1332c609719bSwdenk			HLD1045 display, 640x480.
1333c609719bSwdenk			Active, color, single scan.
1334c609719bSwdenk
1335c609719bSwdenk		CONFIG_OPTREX_BW
1336c609719bSwdenk
1337c609719bSwdenk			Optrex	 CBL50840-2 NF-FW 99 22 M5
1338c609719bSwdenk			or
1339c609719bSwdenk			Hitachi	 LMG6912RPFC-00T
1340c609719bSwdenk			or
1341c609719bSwdenk			Hitachi	 SP14Q002
1342c609719bSwdenk
1343c609719bSwdenk			320x240. Black & white.
1344c609719bSwdenk
1345676d319eSSimon Glass		CONFIG_LCD_ALIGNMENT
1346676d319eSSimon Glass
1347b445bbb4SJeremiah Mahler		Normally the LCD is page-aligned (typically 4KB). If this is
1348676d319eSSimon Glass		defined then the LCD will be aligned to this value instead.
1349676d319eSSimon Glass		For ARM it is sometimes useful to use MMU_SECTION_SIZE
1350676d319eSSimon Glass		here, since it is cheaper to change data cache settings on
1351676d319eSSimon Glass		a per-section basis.
1352676d319eSSimon Glass
1353676d319eSSimon Glass
1354604c7d4aSHannes Petermaier		CONFIG_LCD_ROTATION
1355604c7d4aSHannes Petermaier
1356604c7d4aSHannes Petermaier		Sometimes, for example if the display is mounted in portrait
1357604c7d4aSHannes Petermaier		mode or even if it's mounted landscape but rotated by 180degree,
1358604c7d4aSHannes Petermaier		we need to rotate our content of the display relative to the
1359604c7d4aSHannes Petermaier		framebuffer, so that user can read the messages which are
1360604c7d4aSHannes Petermaier		printed out.
1361604c7d4aSHannes Petermaier		Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1362604c7d4aSHannes Petermaier		initialized with a given rotation from "vl_rot" out of
1363604c7d4aSHannes Petermaier		"vidinfo_t" which is provided by the board specific code.
1364604c7d4aSHannes Petermaier		The value for vl_rot is coded as following (matching to
1365604c7d4aSHannes Petermaier		fbcon=rotate:<n> linux-kernel commandline):
1366604c7d4aSHannes Petermaier		0 = no rotation respectively 0 degree
1367604c7d4aSHannes Petermaier		1 = 90 degree rotation
1368604c7d4aSHannes Petermaier		2 = 180 degree rotation
1369604c7d4aSHannes Petermaier		3 = 270 degree rotation
1370604c7d4aSHannes Petermaier
1371604c7d4aSHannes Petermaier		If CONFIG_LCD_ROTATION is not defined, the console will be
1372604c7d4aSHannes Petermaier		initialized with 0degree rotation.
1373604c7d4aSHannes Petermaier
137445d7f525STom Wai-Hong Tam		CONFIG_LCD_BMP_RLE8
137545d7f525STom Wai-Hong Tam
137645d7f525STom Wai-Hong Tam		Support drawing of RLE8-compressed bitmaps on the LCD.
137745d7f525STom Wai-Hong Tam
1378735987c5STom Wai-Hong Tam		CONFIG_I2C_EDID
1379735987c5STom Wai-Hong Tam
1380735987c5STom Wai-Hong Tam		Enables an 'i2c edid' command which can read EDID
1381735987c5STom Wai-Hong Tam		information over I2C from an attached LCD display.
1382735987c5STom Wai-Hong Tam
13837152b1d0Swdenk- Splash Screen Support: CONFIG_SPLASH_SCREEN
1384d791b1dcSwdenk
1385d791b1dcSwdenk		If this option is set, the environment is checked for
1386d791b1dcSwdenk		a variable "splashimage". If found, the usual display
1387d791b1dcSwdenk		of logo, copyright and system information on the LCD
1388e94d2cd9Swdenk		is suppressed and the BMP image at the address
1389d791b1dcSwdenk		specified in "splashimage" is loaded instead. The
1390d791b1dcSwdenk		console is redirected to the "nulldev", too. This
1391d791b1dcSwdenk		allows for a "silent" boot where a splash screen is
1392d791b1dcSwdenk		loaded very quickly after power-on.
1393d791b1dcSwdenk
1394c0880485SNikita Kiryanov		CONFIG_SPLASHIMAGE_GUARD
1395c0880485SNikita Kiryanov
1396c0880485SNikita Kiryanov		If this option is set, then U-Boot will prevent the environment
1397c0880485SNikita Kiryanov		variable "splashimage" from being set to a problematic address
1398ab5645f1SFabio Estevam		(see doc/README.displaying-bmps).
1399c0880485SNikita Kiryanov		This option is useful for targets where, due to alignment
1400c0880485SNikita Kiryanov		restrictions, an improperly aligned BMP image will cause a data
1401c0880485SNikita Kiryanov		abort. If you think you will not have problems with unaligned
1402c0880485SNikita Kiryanov		accesses (for example because your toolchain prevents them)
1403c0880485SNikita Kiryanov		there is no need to set this option.
1404c0880485SNikita Kiryanov
14051ca298ceSMatthias Weisser		CONFIG_SPLASH_SCREEN_ALIGN
14061ca298ceSMatthias Weisser
14071ca298ceSMatthias Weisser		If this option is set the splash image can be freely positioned
14081ca298ceSMatthias Weisser		on the screen. Environment variable "splashpos" specifies the
14091ca298ceSMatthias Weisser		position as "x,y". If a positive number is given it is used as
14101ca298ceSMatthias Weisser		number of pixel from left/top. If a negative number is given it
14111ca298ceSMatthias Weisser		is used as number of pixel from right/bottom. You can also
14121ca298ceSMatthias Weisser		specify 'm' for centering the image.
14131ca298ceSMatthias Weisser
14141ca298ceSMatthias Weisser		Example:
14151ca298ceSMatthias Weisser		setenv splashpos m,m
14161ca298ceSMatthias Weisser			=> image at center of screen
14171ca298ceSMatthias Weisser
14181ca298ceSMatthias Weisser		setenv splashpos 30,20
14191ca298ceSMatthias Weisser			=> image at x = 30 and y = 20
14201ca298ceSMatthias Weisser
14211ca298ceSMatthias Weisser		setenv splashpos -10,m
14221ca298ceSMatthias Weisser			=> vertically centered image
14231ca298ceSMatthias Weisser			   at x = dspWidth - bmpWidth - 9
14241ca298ceSMatthias Weisser
142598f4a3dfSStefan Roese- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
142698f4a3dfSStefan Roese
142798f4a3dfSStefan Roese		If this option is set, additionally to standard BMP
142898f4a3dfSStefan Roese		images, gzipped BMP images can be displayed via the
142998f4a3dfSStefan Roese		splashscreen support or the bmp command.
143098f4a3dfSStefan Roese
1431d5011762SAnatolij Gustschin- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1432d5011762SAnatolij Gustschin
1433d5011762SAnatolij Gustschin		If this option is set, 8-bit RLE compressed BMP images
1434d5011762SAnatolij Gustschin		can be displayed via the splashscreen support or the
1435d5011762SAnatolij Gustschin		bmp command.
1436d5011762SAnatolij Gustschin
1437c29fdfc1Swdenk- Compression support:
14388ef70478SKees Cook		CONFIG_GZIP
14398ef70478SKees Cook
14408ef70478SKees Cook		Enabled by default to support gzip compressed images.
14418ef70478SKees Cook
1442c29fdfc1Swdenk		CONFIG_BZIP2
1443c29fdfc1Swdenk
1444c29fdfc1Swdenk		If this option is set, support for bzip2 compressed
1445c29fdfc1Swdenk		images is included. If not, only uncompressed and gzip
1446c29fdfc1Swdenk		compressed images are supported.
1447c29fdfc1Swdenk
1448c29fdfc1Swdenk		NOTE: the bzip2 algorithm requires a lot of RAM, so
14496d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1450c29fdfc1Swdenk		be at least 4MB.
1451d791b1dcSwdenk
145217ea1177Swdenk- MII/PHY support:
145317ea1177Swdenk		CONFIG_PHY_ADDR
145417ea1177Swdenk
145517ea1177Swdenk		The address of PHY on MII bus.
145617ea1177Swdenk
145717ea1177Swdenk		CONFIG_PHY_CLOCK_FREQ (ppc4xx)
145817ea1177Swdenk
145917ea1177Swdenk		The clock frequency of the MII bus
146017ea1177Swdenk
146117ea1177Swdenk		CONFIG_PHY_RESET_DELAY
146217ea1177Swdenk
146317ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
146417ea1177Swdenk		reset before any MII register access is possible.
146517ea1177Swdenk		For such PHY, set this option to the usec delay
146617ea1177Swdenk		required. (minimum 300usec for LXT971A)
146717ea1177Swdenk
146817ea1177Swdenk		CONFIG_PHY_CMD_DELAY (ppc4xx)
146917ea1177Swdenk
147017ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
147117ea1177Swdenk		command issued before MII status register can be read
147217ea1177Swdenk
1473c609719bSwdenk- IP address:
1474c609719bSwdenk		CONFIG_IPADDR
1475c609719bSwdenk
1476c609719bSwdenk		Define a default value for the IP address to use for
147711ccc33fSMarcel Ziswiler		the default Ethernet interface, in case this is not
1478c609719bSwdenk		determined through e.g. bootp.
14791ebcd654SWolfgang Denk		(Environment variable "ipaddr")
1480c609719bSwdenk
1481c609719bSwdenk- Server IP address:
1482c609719bSwdenk		CONFIG_SERVERIP
1483c609719bSwdenk
1484c609719bSwdenk		Defines a default value for the IP address of a TFTP
1485c609719bSwdenk		server to contact when using the "tftboot" command.
14861ebcd654SWolfgang Denk		(Environment variable "serverip")
1487c609719bSwdenk
148897cfe861SRobin Getz		CONFIG_KEEP_SERVERADDR
148997cfe861SRobin Getz
149097cfe861SRobin Getz		Keeps the server's MAC address, in the env 'serveraddr'
149197cfe861SRobin Getz		for passing to bootargs (like Linux's netconsole option)
149297cfe861SRobin Getz
14931ebcd654SWolfgang Denk- Gateway IP address:
14941ebcd654SWolfgang Denk		CONFIG_GATEWAYIP
14951ebcd654SWolfgang Denk
14961ebcd654SWolfgang Denk		Defines a default value for the IP address of the
14971ebcd654SWolfgang Denk		default router where packets to other networks are
14981ebcd654SWolfgang Denk		sent to.
14991ebcd654SWolfgang Denk		(Environment variable "gatewayip")
15001ebcd654SWolfgang Denk
15011ebcd654SWolfgang Denk- Subnet mask:
15021ebcd654SWolfgang Denk		CONFIG_NETMASK
15031ebcd654SWolfgang Denk
15041ebcd654SWolfgang Denk		Defines a default value for the subnet mask (or
15051ebcd654SWolfgang Denk		routing prefix) which is used to determine if an IP
15061ebcd654SWolfgang Denk		address belongs to the local subnet or needs to be
15071ebcd654SWolfgang Denk		forwarded through a router.
15081ebcd654SWolfgang Denk		(Environment variable "netmask")
15091ebcd654SWolfgang Denk
151053a5c424SDavid Updegraff- Multicast TFTP Mode:
151153a5c424SDavid Updegraff		CONFIG_MCAST_TFTP
151253a5c424SDavid Updegraff
151353a5c424SDavid Updegraff		Defines whether you want to support multicast TFTP as per
151453a5c424SDavid Updegraff		rfc-2090; for example to work with atftp.  Lets lots of targets
151511ccc33fSMarcel Ziswiler		tftp down the same boot image concurrently.  Note: the Ethernet
151653a5c424SDavid Updegraff		driver in use must provide a function: mcast() to join/leave a
151753a5c424SDavid Updegraff		multicast group.
151853a5c424SDavid Updegraff
1519c609719bSwdenk- BOOTP Recovery Mode:
1520c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY
1521c609719bSwdenk
1522c609719bSwdenk		If you have many targets in a network that try to
1523c609719bSwdenk		boot using BOOTP, you may want to avoid that all
1524c609719bSwdenk		systems send out BOOTP requests at precisely the same
1525c609719bSwdenk		moment (which would happen for instance at recovery
1526c609719bSwdenk		from a power failure, when all systems will try to
1527c609719bSwdenk		boot, thus flooding the BOOTP server. Defining
1528c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1529c609719bSwdenk		inserted before sending out BOOTP requests. The
15306c33c785SWolfgang Denk		following delays are inserted then:
1531c609719bSwdenk
1532c609719bSwdenk		1st BOOTP request:	delay 0 ... 1 sec
1533c609719bSwdenk		2nd BOOTP request:	delay 0 ... 2 sec
1534c609719bSwdenk		3rd BOOTP request:	delay 0 ... 4 sec
1535c609719bSwdenk		4th and following
1536c609719bSwdenk		BOOTP requests:		delay 0 ... 8 sec
1537c609719bSwdenk
153892ac8accSThierry Reding		CONFIG_BOOTP_ID_CACHE_SIZE
153992ac8accSThierry Reding
154092ac8accSThierry Reding		BOOTP packets are uniquely identified using a 32-bit ID. The
154192ac8accSThierry Reding		server will copy the ID from client requests to responses and
154292ac8accSThierry Reding		U-Boot will use this to determine if it is the destination of
154392ac8accSThierry Reding		an incoming response. Some servers will check that addresses
154492ac8accSThierry Reding		aren't in use before handing them out (usually using an ARP
154592ac8accSThierry Reding		ping) and therefore take up to a few hundred milliseconds to
154692ac8accSThierry Reding		respond. Network congestion may also influence the time it
154792ac8accSThierry Reding		takes for a response to make it back to the client. If that
154892ac8accSThierry Reding		time is too long, U-Boot will retransmit requests. In order
154992ac8accSThierry Reding		to allow earlier responses to still be accepted after these
155092ac8accSThierry Reding		retransmissions, U-Boot's BOOTP client keeps a small cache of
155192ac8accSThierry Reding		IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
155292ac8accSThierry Reding		cache. The default is to keep IDs for up to four outstanding
155392ac8accSThierry Reding		requests. Increasing this will allow U-Boot to accept offers
155492ac8accSThierry Reding		from a BOOTP client in networks with unusually high latency.
155592ac8accSThierry Reding
1556fe389a82Sstroese- DHCP Advanced Options:
15571fe80d79SJon Loeliger		You can fine tune the DHCP functionality by defining
15581fe80d79SJon Loeliger		CONFIG_BOOTP_* symbols:
1559fe389a82Sstroese
15601fe80d79SJon Loeliger		CONFIG_BOOTP_SUBNETMASK
15611fe80d79SJon Loeliger		CONFIG_BOOTP_GATEWAY
15621fe80d79SJon Loeliger		CONFIG_BOOTP_HOSTNAME
15631fe80d79SJon Loeliger		CONFIG_BOOTP_NISDOMAIN
15641fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTPATH
15651fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTFILESIZE
15661fe80d79SJon Loeliger		CONFIG_BOOTP_DNS
15671fe80d79SJon Loeliger		CONFIG_BOOTP_DNS2
15681fe80d79SJon Loeliger		CONFIG_BOOTP_SEND_HOSTNAME
15691fe80d79SJon Loeliger		CONFIG_BOOTP_NTPSERVER
15701fe80d79SJon Loeliger		CONFIG_BOOTP_TIMEOFFSET
15711fe80d79SJon Loeliger		CONFIG_BOOTP_VENDOREX
15722c00e099SJoe Hershberger		CONFIG_BOOTP_MAY_FAIL
1573fe389a82Sstroese
15745d110f0aSWilson Callan		CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
15755d110f0aSWilson Callan		environment variable, not the BOOTP server.
1576fe389a82Sstroese
15772c00e099SJoe Hershberger		CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
15782c00e099SJoe Hershberger		after the configured retry count, the call will fail
15792c00e099SJoe Hershberger		instead of starting over.  This can be used to fail over
15802c00e099SJoe Hershberger		to Link-local IP address configuration if the DHCP server
15812c00e099SJoe Hershberger		is not available.
15822c00e099SJoe Hershberger
1583fe389a82Sstroese		CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1584fe389a82Sstroese		serverip from a DHCP server, it is possible that more
1585fe389a82Sstroese		than one DNS serverip is offered to the client.
1586fe389a82Sstroese		If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1587fe389a82Sstroese		serverip will be stored in the additional environment
1588fe389a82Sstroese		variable "dnsip2". The first DNS serverip is always
1589fe389a82Sstroese		stored in the variable "dnsip", when CONFIG_BOOTP_DNS
15901fe80d79SJon Loeliger		is defined.
1591fe389a82Sstroese
1592fe389a82Sstroese		CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1593fe389a82Sstroese		to do a dynamic update of a DNS server. To do this, they
1594fe389a82Sstroese		need the hostname of the DHCP requester.
15955d110f0aSWilson Callan		If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
15961fe80d79SJon Loeliger		of the "hostname" environment variable is passed as
15971fe80d79SJon Loeliger		option 12 to the DHCP server.
1598fe389a82Sstroese
1599d9a2f416SAras Vaichas		CONFIG_BOOTP_DHCP_REQUEST_DELAY
1600d9a2f416SAras Vaichas
1601d9a2f416SAras Vaichas		A 32bit value in microseconds for a delay between
1602d9a2f416SAras Vaichas		receiving a "DHCP Offer" and sending the "DHCP Request".
1603d9a2f416SAras Vaichas		This fixes a problem with certain DHCP servers that don't
1604d9a2f416SAras Vaichas		respond 100% of the time to a "DHCP request". E.g. On an
1605d9a2f416SAras Vaichas		AT91RM9200 processor running at 180MHz, this delay needed
1606d9a2f416SAras Vaichas		to be *at least* 15,000 usec before a Windows Server 2003
1607d9a2f416SAras Vaichas		DHCP server would reply 100% of the time. I recommend at
1608d9a2f416SAras Vaichas		least 50,000 usec to be safe. The alternative is to hope
1609d9a2f416SAras Vaichas		that one of the retries will be successful but note that
1610d9a2f416SAras Vaichas		the DHCP timeout and retry process takes a longer than
1611d9a2f416SAras Vaichas		this delay.
1612d9a2f416SAras Vaichas
1613d22c338eSJoe Hershberger - Link-local IP address negotiation:
1614d22c338eSJoe Hershberger		Negotiate with other link-local clients on the local network
1615d22c338eSJoe Hershberger		for an address that doesn't require explicit configuration.
1616d22c338eSJoe Hershberger		This is especially useful if a DHCP server cannot be guaranteed
1617d22c338eSJoe Hershberger		to exist in all environments that the device must operate.
1618d22c338eSJoe Hershberger
1619d22c338eSJoe Hershberger		See doc/README.link-local for more information.
1620d22c338eSJoe Hershberger
1621a3d991bdSwdenk - CDP Options:
1622a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID
1623a3d991bdSwdenk
1624a3d991bdSwdenk		The device id used in CDP trigger frames.
1625a3d991bdSwdenk
1626a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID_PREFIX
1627a3d991bdSwdenk
1628a3d991bdSwdenk		A two character string which is prefixed to the MAC address
1629a3d991bdSwdenk		of the device.
1630a3d991bdSwdenk
1631a3d991bdSwdenk		CONFIG_CDP_PORT_ID
1632a3d991bdSwdenk
1633a3d991bdSwdenk		A printf format string which contains the ascii name of
1634a3d991bdSwdenk		the port. Normally is set to "eth%d" which sets
163511ccc33fSMarcel Ziswiler		eth0 for the first Ethernet, eth1 for the second etc.
1636a3d991bdSwdenk
1637a3d991bdSwdenk		CONFIG_CDP_CAPABILITIES
1638a3d991bdSwdenk
1639a3d991bdSwdenk		A 32bit integer which indicates the device capabilities;
1640a3d991bdSwdenk		0x00000010 for a normal host which does not forwards.
1641a3d991bdSwdenk
1642a3d991bdSwdenk		CONFIG_CDP_VERSION
1643a3d991bdSwdenk
1644a3d991bdSwdenk		An ascii string containing the version of the software.
1645a3d991bdSwdenk
1646a3d991bdSwdenk		CONFIG_CDP_PLATFORM
1647a3d991bdSwdenk
1648a3d991bdSwdenk		An ascii string containing the name of the platform.
1649a3d991bdSwdenk
1650a3d991bdSwdenk		CONFIG_CDP_TRIGGER
1651a3d991bdSwdenk
1652a3d991bdSwdenk		A 32bit integer sent on the trigger.
1653a3d991bdSwdenk
1654a3d991bdSwdenk		CONFIG_CDP_POWER_CONSUMPTION
1655a3d991bdSwdenk
1656a3d991bdSwdenk		A 16bit integer containing the power consumption of the
1657a3d991bdSwdenk		device in .1 of milliwatts.
1658a3d991bdSwdenk
1659a3d991bdSwdenk		CONFIG_CDP_APPLIANCE_VLAN_TYPE
1660a3d991bdSwdenk
1661a3d991bdSwdenk		A byte containing the id of the VLAN.
1662a3d991bdSwdenk
166379267eddSUri Mashiach- Status LED:	CONFIG_LED_STATUS
1664c609719bSwdenk
1665c609719bSwdenk		Several configurations allow to display the current
1666c609719bSwdenk		status using a LED. For instance, the LED will blink
1667c609719bSwdenk		fast while running U-Boot code, stop blinking as
1668c609719bSwdenk		soon as a reply to a BOOTP request was received, and
1669c609719bSwdenk		start blinking slow once the Linux kernel is running
1670c609719bSwdenk		(supported by a status LED driver in the Linux
167179267eddSUri Mashiach		kernel). Defining CONFIG_LED_STATUS enables this
1672c609719bSwdenk		feature in U-Boot.
1673c609719bSwdenk
16741df7bbbaSIgor Grinberg		Additional options:
16751df7bbbaSIgor Grinberg
167679267eddSUri Mashiach		CONFIG_LED_STATUS_GPIO
16771df7bbbaSIgor Grinberg		The status LED can be connected to a GPIO pin.
16781df7bbbaSIgor Grinberg		In such cases, the gpio_led driver can be used as a
167979267eddSUri Mashiach		status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
16801df7bbbaSIgor Grinberg		to include the gpio_led driver in the U-Boot binary.
16811df7bbbaSIgor Grinberg
16829dfdcdfeSIgor Grinberg		CONFIG_GPIO_LED_INVERTED_TABLE
16839dfdcdfeSIgor Grinberg		Some GPIO connected LEDs may have inverted polarity in which
16849dfdcdfeSIgor Grinberg		case the GPIO high value corresponds to LED off state and
16859dfdcdfeSIgor Grinberg		GPIO low value corresponds to LED on state.
16869dfdcdfeSIgor Grinberg		In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
16879dfdcdfeSIgor Grinberg		with a list of GPIO LEDs that have inverted polarity.
16889dfdcdfeSIgor Grinberg
16893f4978c7SHeiko Schocher- I2C Support:	CONFIG_SYS_I2C
1690c609719bSwdenk
16913f4978c7SHeiko Schocher		This enable the NEW i2c subsystem, and will allow you to use
16923f4978c7SHeiko Schocher		i2c commands at the u-boot command line (as long as you set
16933f4978c7SHeiko Schocher		CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
16943f4978c7SHeiko Schocher		based realtime clock chips or other i2c devices. See
16953f4978c7SHeiko Schocher		common/cmd_i2c.c for a description of the command line
16963f4978c7SHeiko Schocher		interface.
16973f4978c7SHeiko Schocher
16983f4978c7SHeiko Schocher		ported i2c driver to the new framework:
1699ea818dbbSHeiko Schocher		- drivers/i2c/soft_i2c.c:
1700ea818dbbSHeiko Schocher		  - activate first bus with CONFIG_SYS_I2C_SOFT define
1701ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1702ea818dbbSHeiko Schocher		    for defining speed and slave address
1703ea818dbbSHeiko Schocher		  - activate second bus with I2C_SOFT_DECLARATIONS2 define
1704ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1705ea818dbbSHeiko Schocher		    for defining speed and slave address
1706ea818dbbSHeiko Schocher		  - activate third bus with I2C_SOFT_DECLARATIONS3 define
1707ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1708ea818dbbSHeiko Schocher		    for defining speed and slave address
1709ea818dbbSHeiko Schocher		  - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1710ea818dbbSHeiko Schocher		    CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1711ea818dbbSHeiko Schocher		    for defining speed and slave address
17123f4978c7SHeiko Schocher
171300f792e0SHeiko Schocher		- drivers/i2c/fsl_i2c.c:
171400f792e0SHeiko Schocher		  - activate i2c driver with CONFIG_SYS_I2C_FSL
171500f792e0SHeiko Schocher		    define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
171600f792e0SHeiko Schocher		    offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
171700f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
171800f792e0SHeiko Schocher		    bus.
171900f792e0SHeiko Schocher		  - If your board supports a second fsl i2c bus, define
172000f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
172100f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C2_SPEED for the speed and
172200f792e0SHeiko Schocher		    CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
172300f792e0SHeiko Schocher		    second bus.
172400f792e0SHeiko Schocher
17251f2ba722SSimon Glass		- drivers/i2c/tegra_i2c.c:
17261f2ba722SSimon Glass		  - activate this driver with CONFIG_SYS_I2C_TEGRA
17271f2ba722SSimon Glass		  - This driver adds 4 i2c buses with a fix speed from
17281f2ba722SSimon Glass		    100000 and the slave addr 0!
17291f2ba722SSimon Glass
1730880540deSDirk Eibach		- drivers/i2c/ppc4xx_i2c.c
1731880540deSDirk Eibach		  - activate this driver with CONFIG_SYS_I2C_PPC4XX
1732880540deSDirk Eibach		  - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1733880540deSDirk Eibach		  - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1734880540deSDirk Eibach
1735fac96408Strem		- drivers/i2c/i2c_mxc.c
1736fac96408Strem		  - activate this driver with CONFIG_SYS_I2C_MXC
173703544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
173803544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
173903544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
174003544c66SAlbert ARIBAUD \\(3ADEV\\)		  - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
1741fac96408Strem		  - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1742fac96408Strem		  - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1743fac96408Strem		  - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1744fac96408Strem		  - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1745fac96408Strem		  - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1746fac96408Strem		  - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
174703544c66SAlbert ARIBAUD \\(3ADEV\\)		  - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
174803544c66SAlbert ARIBAUD \\(3ADEV\\)		  - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
1749b445bbb4SJeremiah Mahler		If those defines are not set, default value is 100000
1750fac96408Strem		for speed, and 0 for slave.
1751fac96408Strem
17521086bfa9SNobuhiro Iwamatsu		- drivers/i2c/rcar_i2c.c:
17531086bfa9SNobuhiro Iwamatsu		  - activate this driver with CONFIG_SYS_I2C_RCAR
17541086bfa9SNobuhiro Iwamatsu		  - This driver adds 4 i2c buses
17551086bfa9SNobuhiro Iwamatsu
17561086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
17571086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
17581086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
17591086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
17601086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
17611086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
17621086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
17631086bfa9SNobuhiro Iwamatsu		  - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
17641086bfa9SNobuhiro Iwamatsu		  - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
17651086bfa9SNobuhiro Iwamatsu
17662035d77dSNobuhiro Iwamatsu		- drivers/i2c/sh_i2c.c:
17672035d77dSNobuhiro Iwamatsu		  - activate this driver with CONFIG_SYS_I2C_SH
17682035d77dSNobuhiro Iwamatsu		  - This driver adds from 2 to 5 i2c buses
17692035d77dSNobuhiro Iwamatsu
17702035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
17712035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
17722035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
17732035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
17742035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
17752035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
17762035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
17772035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
17782035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
17792035d77dSNobuhiro Iwamatsu		  - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
1780b445bbb4SJeremiah Mahler		  - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
17812035d77dSNobuhiro Iwamatsu
17826789e84eSHeiko Schocher		- drivers/i2c/omap24xx_i2c.c
17836789e84eSHeiko Schocher		  - activate this driver with CONFIG_SYS_I2C_OMAP24XX
17846789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
17856789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
17866789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
17876789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
17886789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
17896789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
17906789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
17916789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
17926789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
17936789e84eSHeiko Schocher		  - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
17946789e84eSHeiko Schocher
17950bdffe71SHeiko Schocher		- drivers/i2c/zynq_i2c.c
17960bdffe71SHeiko Schocher		  - activate this driver with CONFIG_SYS_I2C_ZYNQ
17970bdffe71SHeiko Schocher		  - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
17980bdffe71SHeiko Schocher		  - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
17990bdffe71SHeiko Schocher
1800e717fc6dSNaveen Krishna Ch		- drivers/i2c/s3c24x0_i2c.c:
1801e717fc6dSNaveen Krishna Ch		  - activate this driver with CONFIG_SYS_I2C_S3C24X0
1802e717fc6dSNaveen Krishna Ch		  - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1803e717fc6dSNaveen Krishna Ch		    9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1804e717fc6dSNaveen Krishna Ch		    with a fix speed from 100000 and the slave addr 0!
1805e717fc6dSNaveen Krishna Ch
1806b46226bdSDirk Eibach		- drivers/i2c/ihs_i2c.c
1807b46226bdSDirk Eibach		  - activate this driver with CONFIG_SYS_I2C_IHS
1808b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1809b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1810b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1811b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1812b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1813b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1814b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1815b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1816b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1817b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1818b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1819b46226bdSDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
1820071be896SDirk Eibach		  - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1821071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1822071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1823071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1824071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1825071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1826071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1827071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1828071be896SDirk Eibach		  - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
1829b46226bdSDirk Eibach
18303f4978c7SHeiko Schocher		additional defines:
18313f4978c7SHeiko Schocher
18323f4978c7SHeiko Schocher		CONFIG_SYS_NUM_I2C_BUSES
1833945a18e6SSimon Glass		Hold the number of i2c buses you want to use.
18343f4978c7SHeiko Schocher
18353f4978c7SHeiko Schocher		CONFIG_SYS_I2C_DIRECT_BUS
18363f4978c7SHeiko Schocher		define this, if you don't use i2c muxes on your hardware.
18373f4978c7SHeiko Schocher		if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
18383f4978c7SHeiko Schocher		omit this define.
18393f4978c7SHeiko Schocher
18403f4978c7SHeiko Schocher		CONFIG_SYS_I2C_MAX_HOPS
18413f4978c7SHeiko Schocher		define how many muxes are maximal consecutively connected
18423f4978c7SHeiko Schocher		on one i2c bus. If you not use i2c muxes, omit this
18433f4978c7SHeiko Schocher		define.
18443f4978c7SHeiko Schocher
18453f4978c7SHeiko Schocher		CONFIG_SYS_I2C_BUSES
1846b445bbb4SJeremiah Mahler		hold a list of buses you want to use, only used if
18473f4978c7SHeiko Schocher		CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
18483f4978c7SHeiko Schocher		a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
18493f4978c7SHeiko Schocher		CONFIG_SYS_NUM_I2C_BUSES = 9:
18503f4978c7SHeiko Schocher
18513f4978c7SHeiko Schocher		 CONFIG_SYS_I2C_BUSES	{{0, {I2C_NULL_HOP}}, \
18523f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
18533f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
18543f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
18553f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
18563f4978c7SHeiko Schocher					{0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
18573f4978c7SHeiko Schocher					{1, {I2C_NULL_HOP}}, \
18583f4978c7SHeiko Schocher					{1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
18593f4978c7SHeiko Schocher					{1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
18603f4978c7SHeiko Schocher					}
18613f4978c7SHeiko Schocher
18623f4978c7SHeiko Schocher		which defines
18633f4978c7SHeiko Schocher			bus 0 on adapter 0 without a mux
1864ea818dbbSHeiko Schocher			bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1865ea818dbbSHeiko Schocher			bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1866ea818dbbSHeiko Schocher			bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1867ea818dbbSHeiko Schocher			bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1868ea818dbbSHeiko Schocher			bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
18693f4978c7SHeiko Schocher			bus 6 on adapter 1 without a mux
1870ea818dbbSHeiko Schocher			bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1871ea818dbbSHeiko Schocher			bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
18723f4978c7SHeiko Schocher
18733f4978c7SHeiko Schocher		If you do not have i2c muxes on your board, omit this define.
18743f4978c7SHeiko Schocher
1875ce3b5d69SSimon Glass- Legacy I2C Support:
1876ea818dbbSHeiko Schocher		If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
1877b37c7e5eSwdenk		then the following macros need to be defined (examples are
1878b37c7e5eSwdenk		from include/configs/lwmon.h):
1879c609719bSwdenk
1880c609719bSwdenk		I2C_INIT
1881c609719bSwdenk
1882b37c7e5eSwdenk		(Optional). Any commands necessary to enable the I2C
1883c609719bSwdenk		controller or configure ports.
1884c609719bSwdenk
1885b37c7e5eSwdenk		eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |=	PB_SCL)
1886b37c7e5eSwdenk
1887c609719bSwdenk		I2C_ACTIVE
1888c609719bSwdenk
1889c609719bSwdenk		The code necessary to make the I2C data line active
1890c609719bSwdenk		(driven).  If the data line is open collector, this
1891c609719bSwdenk		define can be null.
1892c609719bSwdenk
1893b37c7e5eSwdenk		eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |=  PB_SDA)
1894b37c7e5eSwdenk
1895c609719bSwdenk		I2C_TRISTATE
1896c609719bSwdenk
1897c609719bSwdenk		The code necessary to make the I2C data line tri-stated
1898c609719bSwdenk		(inactive).  If the data line is open collector, this
1899c609719bSwdenk		define can be null.
1900c609719bSwdenk
1901b37c7e5eSwdenk		eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1902b37c7e5eSwdenk
1903c609719bSwdenk		I2C_READ
1904c609719bSwdenk
1905472d5460SYork Sun		Code that returns true if the I2C data line is high,
1906472d5460SYork Sun		false if it is low.
1907c609719bSwdenk
1908b37c7e5eSwdenk		eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1909b37c7e5eSwdenk
1910c609719bSwdenk		I2C_SDA(bit)
1911c609719bSwdenk
1912472d5460SYork Sun		If <bit> is true, sets the I2C data line high. If it
1913472d5460SYork Sun		is false, it clears it (low).
1914c609719bSwdenk
1915b37c7e5eSwdenk		eg: #define I2C_SDA(bit) \
1916b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SDA; \
1917b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SDA
1918b37c7e5eSwdenk
1919c609719bSwdenk		I2C_SCL(bit)
1920c609719bSwdenk
1921472d5460SYork Sun		If <bit> is true, sets the I2C clock line high. If it
1922472d5460SYork Sun		is false, it clears it (low).
1923c609719bSwdenk
1924b37c7e5eSwdenk		eg: #define I2C_SCL(bit) \
1925b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SCL; \
1926b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SCL
1927b37c7e5eSwdenk
1928c609719bSwdenk		I2C_DELAY
1929c609719bSwdenk
1930c609719bSwdenk		This delay is invoked four times per clock cycle so this
1931c609719bSwdenk		controls the rate of data transfer.  The data rate thus
1932b37c7e5eSwdenk		is 1 / (I2C_DELAY * 4). Often defined to be something
1933b37c7e5eSwdenk		like:
1934b37c7e5eSwdenk
1935b37c7e5eSwdenk		#define I2C_DELAY  udelay(2)
1936c609719bSwdenk
1937793b5726SMike Frysinger		CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1938793b5726SMike Frysinger
1939793b5726SMike Frysinger		If your arch supports the generic GPIO framework (asm/gpio.h),
1940793b5726SMike Frysinger		then you may alternatively define the two GPIOs that are to be
1941793b5726SMike Frysinger		used as SCL / SDA.  Any of the previous I2C_xxx macros will
1942793b5726SMike Frysinger		have GPIO-based defaults assigned to them as appropriate.
1943793b5726SMike Frysinger
1944793b5726SMike Frysinger		You should define these to the GPIO value as given directly to
1945793b5726SMike Frysinger		the generic GPIO functions.
1946793b5726SMike Frysinger
19476d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_I2C_INIT_BOARD
194847cd00faSwdenk
194947cd00faSwdenk		When a board is reset during an i2c bus transfer
195047cd00faSwdenk		chips might think that the current transfer is still
195147cd00faSwdenk		in progress. On some boards it is possible to access
195247cd00faSwdenk		the i2c SCLK line directly, either by using the
195347cd00faSwdenk		processor pin as a GPIO or by having a second pin
195447cd00faSwdenk		connected to the bus. If this option is defined a
195547cd00faSwdenk		custom i2c_init_board() routine in boards/xxx/board.c
195647cd00faSwdenk		is run early in the boot sequence.
195747cd00faSwdenk
1958bb99ad6dSBen Warren		CONFIG_I2C_MULTI_BUS
1959bb99ad6dSBen Warren
1960bb99ad6dSBen Warren		This option allows the use of multiple I2C buses, each of which
1961bb99ad6dSBen Warren		must have a controller.	 At any point in time, only one bus is
1962bb99ad6dSBen Warren		active.	 To switch to a different bus, use the 'i2c dev' command.
1963bb99ad6dSBen Warren		Note that bus numbering is zero-based.
1964bb99ad6dSBen Warren
19656d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_I2C_NOPROBES
1966bb99ad6dSBen Warren
1967bb99ad6dSBen Warren		This option specifies a list of I2C devices that will be skipped
19680f89c54bSPeter Tyser		when the 'i2c probe' command is issued.	 If CONFIG_I2C_MULTI_BUS
19690f89c54bSPeter Tyser		is set, specify a list of bus-device pairs.  Otherwise, specify
19700f89c54bSPeter Tyser		a 1D array of device addresses
1971bb99ad6dSBen Warren
1972bb99ad6dSBen Warren		e.g.
1973bb99ad6dSBen Warren			#undef	CONFIG_I2C_MULTI_BUS
19746d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			#define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1975bb99ad6dSBen Warren
1976bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on a board with one I2C bus
1977bb99ad6dSBen Warren
1978bb99ad6dSBen Warren			#define CONFIG_I2C_MULTI_BUS
1979945a18e6SSimon Glass			#define CONFIG_SYS_I2C_NOPROBES	{{0,0x50},{0,0x68},{1,0x54}}
1980bb99ad6dSBen Warren
1981bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1982bb99ad6dSBen Warren
19836d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SPD_BUS_NUM
1984be5e6181STimur Tabi
1985be5e6181STimur Tabi		If defined, then this indicates the I2C bus number for DDR SPD.
1986be5e6181STimur Tabi		If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1987be5e6181STimur Tabi
19886d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_RTC_BUS_NUM
19890dc018ecSStefan Roese
19900dc018ecSStefan Roese		If defined, then this indicates the I2C bus number for the RTC.
19910dc018ecSStefan Roese		If not defined, then U-Boot assumes that RTC is on I2C bus 0.
19920dc018ecSStefan Roese
19932ac6985aSAndrew Dyer		CONFIG_SOFT_I2C_READ_REPEATED_START
19942ac6985aSAndrew Dyer
19952ac6985aSAndrew Dyer		defining this will force the i2c_read() function in
19962ac6985aSAndrew Dyer		the soft_i2c driver to perform an I2C repeated start
19972ac6985aSAndrew Dyer		between writing the address pointer and reading the
19982ac6985aSAndrew Dyer		data.  If this define is omitted the default behaviour
19992ac6985aSAndrew Dyer		of doing a stop-start sequence will be used.  Most I2C
20002ac6985aSAndrew Dyer		devices can use either method, but some require one or
20012ac6985aSAndrew Dyer		the other.
2002be5e6181STimur Tabi
2003c609719bSwdenk- SPI Support:	CONFIG_SPI
2004c609719bSwdenk
2005c609719bSwdenk		Enables SPI driver (so far only tested with
2006c609719bSwdenk		SPI EEPROM, also an instance works with Crystal A/D and
2007c609719bSwdenk		D/As on the SACSng board)
2008c609719bSwdenk
20096639562eSYoshihiro Shimoda		CONFIG_SH_SPI
20106639562eSYoshihiro Shimoda
20116639562eSYoshihiro Shimoda		Enables the driver for SPI controller on SuperH. Currently
20126639562eSYoshihiro Shimoda		only SH7757 is supported.
20136639562eSYoshihiro Shimoda
2014c609719bSwdenk		CONFIG_SOFT_SPI
2015c609719bSwdenk
2016c609719bSwdenk		Enables a software (bit-bang) SPI driver rather than
2017c609719bSwdenk		using hardware support. This is a general purpose
2018c609719bSwdenk		driver that only requires three general I/O port pins
2019c609719bSwdenk		(two outputs, one input) to function. If this is
2020c609719bSwdenk		defined, the board configuration must define several
2021c609719bSwdenk		SPI configuration items (port pins to use, etc). For
2022c609719bSwdenk		an example, see include/configs/sacsng.h.
2023c609719bSwdenk
202404a9e118SBen Warren		CONFIG_HARD_SPI
202504a9e118SBen Warren
202604a9e118SBen Warren		Enables a hardware SPI driver for general-purpose reads
202704a9e118SBen Warren		and writes.  As with CONFIG_SOFT_SPI, the board configuration
202804a9e118SBen Warren		must define a list of chip-select function pointers.
202904a9e118SBen Warren		Currently supported on some MPC8xxx processors.	 For an
203004a9e118SBen Warren		example, see include/configs/mpc8349emds.h.
203104a9e118SBen Warren
203238254f45SGuennadi Liakhovetski		CONFIG_MXC_SPI
203338254f45SGuennadi Liakhovetski
203438254f45SGuennadi Liakhovetski		Enables the driver for the SPI controllers on i.MX and MXC
20352e3cd1cdSFabio Estevam		SoCs. Currently i.MX31/35/51 are supported.
203638254f45SGuennadi Liakhovetski
2037f659b573SHeiko Schocher		CONFIG_SYS_SPI_MXC_WAIT
2038f659b573SHeiko Schocher		Timeout for waiting until spi transfer completed.
2039f659b573SHeiko Schocher		default: (CONFIG_SYS_HZ/100)     /* 10 ms */
2040f659b573SHeiko Schocher
20410133502eSMatthias Fuchs- FPGA Support: CONFIG_FPGA
20420133502eSMatthias Fuchs
20430133502eSMatthias Fuchs		Enables FPGA subsystem.
20440133502eSMatthias Fuchs
20450133502eSMatthias Fuchs		CONFIG_FPGA_<vendor>
20460133502eSMatthias Fuchs
20470133502eSMatthias Fuchs		Enables support for specific chip vendors.
20480133502eSMatthias Fuchs		(ALTERA, XILINX)
20490133502eSMatthias Fuchs
20500133502eSMatthias Fuchs		CONFIG_FPGA_<family>
20510133502eSMatthias Fuchs
20520133502eSMatthias Fuchs		Enables support for FPGA family.
20530133502eSMatthias Fuchs		(SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
20540133502eSMatthias Fuchs
20550133502eSMatthias Fuchs		CONFIG_FPGA_COUNT
2056c609719bSwdenk
2057c609719bSwdenk		Specify the number of FPGA devices to support.
2058c609719bSwdenk
20596d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_PROG_FEEDBACK
2060c609719bSwdenk
2061c609719bSwdenk		Enable printing of hash marks during FPGA configuration.
2062c609719bSwdenk
20636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_BUSY
2064c609719bSwdenk
2065c609719bSwdenk		Enable checks on FPGA configuration interface busy
2066c609719bSwdenk		status by the configuration function. This option
2067c609719bSwdenk		will require a board or device specific function to
2068c609719bSwdenk		be written.
2069c609719bSwdenk
2070c609719bSwdenk		CONFIG_FPGA_DELAY
2071c609719bSwdenk
2072c609719bSwdenk		If defined, a function that provides delays in the FPGA
2073c609719bSwdenk		configuration driver.
2074c609719bSwdenk
20756d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_CTRLC
2076c609719bSwdenk		Allow Control-C to interrupt FPGA configuration
2077c609719bSwdenk
20786d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_ERROR
2079c609719bSwdenk
2080c609719bSwdenk		Check for configuration errors during FPGA bitfile
2081c609719bSwdenk		loading. For example, abort during Virtex II
2082c609719bSwdenk		configuration if the INIT_B line goes low (which
2083c609719bSwdenk		indicated a CRC error).
2084c609719bSwdenk
20856d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_INIT
2086c609719bSwdenk
2087b445bbb4SJeremiah Mahler		Maximum time to wait for the INIT_B line to de-assert
2088b445bbb4SJeremiah Mahler		after PROB_B has been de-asserted during a Virtex II
2089c609719bSwdenk		FPGA configuration sequence. The default time is 500
209011ccc33fSMarcel Ziswiler		ms.
2091c609719bSwdenk
20926d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_BUSY
2093c609719bSwdenk
2094b445bbb4SJeremiah Mahler		Maximum time to wait for BUSY to de-assert during
209511ccc33fSMarcel Ziswiler		Virtex II FPGA configuration. The default is 5 ms.
2096c609719bSwdenk
20976d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_CONFIG
2098c609719bSwdenk
2099c609719bSwdenk		Time to wait after FPGA configuration. The default is
210011ccc33fSMarcel Ziswiler		200 ms.
2101c609719bSwdenk
2102c609719bSwdenk- Configuration Management:
2103b2b8a696SStefan Roese		CONFIG_BUILD_TARGET
2104b2b8a696SStefan Roese
2105b2b8a696SStefan Roese		Some SoCs need special image types (e.g. U-Boot binary
2106b2b8a696SStefan Roese		with a special header) as build targets. By defining
2107b2b8a696SStefan Roese		CONFIG_BUILD_TARGET in the SoC / board header, this
2108b2b8a696SStefan Roese		special image will be automatically built upon calling
21096de80f21SSimon Glass		make / buildman.
2110b2b8a696SStefan Roese
2111c609719bSwdenk		CONFIG_IDENT_STRING
2112c609719bSwdenk
2113c609719bSwdenk		If defined, this string will be added to the U-Boot
2114c609719bSwdenk		version information (U_BOOT_VERSION)
2115c609719bSwdenk
2116c609719bSwdenk- Vendor Parameter Protection:
2117c609719bSwdenk
2118c609719bSwdenk		U-Boot considers the values of the environment
2119c609719bSwdenk		variables "serial#" (Board Serial Number) and
21207152b1d0Swdenk		"ethaddr" (Ethernet Address) to be parameters that
2121c609719bSwdenk		are set once by the board vendor / manufacturer, and
2122c609719bSwdenk		protects these variables from casual modification by
2123c609719bSwdenk		the user. Once set, these variables are read-only,
2124c609719bSwdenk		and write or delete attempts are rejected. You can
212511ccc33fSMarcel Ziswiler		change this behaviour:
2126c609719bSwdenk
2127c609719bSwdenk		If CONFIG_ENV_OVERWRITE is #defined in your config
2128c609719bSwdenk		file, the write protection for vendor parameters is
212947cd00faSwdenk		completely disabled. Anybody can change or delete
2130c609719bSwdenk		these parameters.
2131c609719bSwdenk
213292ac5208SJoe Hershberger		Alternatively, if you define _both_ an ethaddr in the
213392ac5208SJoe Hershberger		default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
213411ccc33fSMarcel Ziswiler		Ethernet address is installed in the environment,
2135c609719bSwdenk		which can be changed exactly ONCE by the user. [The
2136c609719bSwdenk		serial# is unaffected by this, i. e. it remains
2137c609719bSwdenk		read-only.]
2138c609719bSwdenk
21392598090bSJoe Hershberger		The same can be accomplished in a more flexible way
21402598090bSJoe Hershberger		for any variable by configuring the type of access
21412598090bSJoe Hershberger		to allow for those variables in the ".flags" variable
21422598090bSJoe Hershberger		or define CONFIG_ENV_FLAGS_LIST_STATIC.
21432598090bSJoe Hershberger
2144c609719bSwdenk- Protected RAM:
2145c609719bSwdenk		CONFIG_PRAM
2146c609719bSwdenk
2147c609719bSwdenk		Define this variable to enable the reservation of
2148c609719bSwdenk		"protected RAM", i. e. RAM which is not overwritten
2149c609719bSwdenk		by U-Boot. Define CONFIG_PRAM to hold the number of
2150c609719bSwdenk		kB you want to reserve for pRAM. You can overwrite
2151c609719bSwdenk		this default value by defining an environment
2152c609719bSwdenk		variable "pram" to the number of kB you want to
2153c609719bSwdenk		reserve. Note that the board info structure will
2154c609719bSwdenk		still show the full amount of RAM. If pRAM is
2155c609719bSwdenk		reserved, a new environment variable "mem" will
2156c609719bSwdenk		automatically be defined to hold the amount of
2157c609719bSwdenk		remaining RAM in a form that can be passed as boot
2158c609719bSwdenk		argument to Linux, for instance like that:
2159c609719bSwdenk
2160fe126d8bSWolfgang Denk			setenv bootargs ... mem=\${mem}
2161c609719bSwdenk			saveenv
2162c609719bSwdenk
2163c609719bSwdenk		This way you can tell Linux not to use this memory,
2164c609719bSwdenk		either, which results in a memory region that will
2165c609719bSwdenk		not be affected by reboots.
2166c609719bSwdenk
2167c609719bSwdenk		*WARNING* If your board configuration uses automatic
2168c609719bSwdenk		detection of the RAM size, you must make sure that
2169c609719bSwdenk		this memory test is non-destructive. So far, the
2170c609719bSwdenk		following board configurations are known to be
2171c609719bSwdenk		"pRAM-clean":
2172c609719bSwdenk
21735b8e76c3SHeiko Schocher			IVMS8, IVML24, SPD8xx,
21741b0757ecSWolfgang Denk			HERMES, IP860, RPXlite, LWMON,
21752eb48ff7SHeiko Schocher			FLAGADM
2176c609719bSwdenk
217740fef049SGabe Black- Access to physical memory region (> 4GB)
217840fef049SGabe Black		Some basic support is provided for operations on memory not
217940fef049SGabe Black		normally accessible to U-Boot - e.g. some architectures
218040fef049SGabe Black		support access to more than 4GB of memory on 32-bit
218140fef049SGabe Black		machines using physical address extension or similar.
218240fef049SGabe Black		Define CONFIG_PHYSMEM to access this basic support, which
218340fef049SGabe Black		currently only supports clearing the memory.
218440fef049SGabe Black
2185c609719bSwdenk- Error Recovery:
2186c609719bSwdenk		CONFIG_PANIC_HANG
2187c609719bSwdenk
2188c609719bSwdenk		Define this variable to stop the system in case of a
2189c609719bSwdenk		fatal error, so that you have to reset it manually.
2190c609719bSwdenk		This is probably NOT a good idea for an embedded
219111ccc33fSMarcel Ziswiler		system where you want the system to reboot
2192c609719bSwdenk		automatically as fast as possible, but it may be
2193c609719bSwdenk		useful during development since you can try to debug
2194c609719bSwdenk		the conditions that lead to the situation.
2195c609719bSwdenk
2196c609719bSwdenk		CONFIG_NET_RETRY_COUNT
2197c609719bSwdenk
2198c609719bSwdenk		This variable defines the number of retries for
2199c609719bSwdenk		network operations like ARP, RARP, TFTP, or BOOTP
2200c609719bSwdenk		before giving up the operation. If not defined, a
2201c609719bSwdenk		default value of 5 is used.
2202c609719bSwdenk
220340cb90eeSGuennadi Liakhovetski		CONFIG_ARP_TIMEOUT
220440cb90eeSGuennadi Liakhovetski
220540cb90eeSGuennadi Liakhovetski		Timeout waiting for an ARP reply in milliseconds.
220640cb90eeSGuennadi Liakhovetski
220748a3e999STetsuyuki Kobayashi		CONFIG_NFS_TIMEOUT
220848a3e999STetsuyuki Kobayashi
220948a3e999STetsuyuki Kobayashi		Timeout in milliseconds used in NFS protocol.
221048a3e999STetsuyuki Kobayashi		If you encounter "ERROR: Cannot umount" in nfs command,
221148a3e999STetsuyuki Kobayashi		try longer timeout such as
221248a3e999STetsuyuki Kobayashi		#define CONFIG_NFS_TIMEOUT 10000UL
221348a3e999STetsuyuki Kobayashi
2214c609719bSwdenk- Command Interpreter:
22158078f1a5SWolfgang Denk		CONFIG_AUTO_COMPLETE
221604a85b3bSwdenk
221704a85b3bSwdenk		Enable auto completion of commands using TAB.
221804a85b3bSwdenk
22196d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_PROMPT_HUSH_PS2
2220c609719bSwdenk
2221c609719bSwdenk		This defines the secondary prompt string, which is
2222c609719bSwdenk		printed when the command interpreter needs more input
2223c609719bSwdenk		to complete a command. Usually "> ".
2224c609719bSwdenk
2225c609719bSwdenk	Note:
2226c609719bSwdenk
2227c609719bSwdenk		In the current implementation, the local variables
2228c609719bSwdenk		space and global environment variables space are
2229c609719bSwdenk		separated. Local variables are those you define by
22303b57fe0aSwdenk		simply typing `name=value'. To access a local
2231c609719bSwdenk		variable later on, you have write `$name' or
22323b57fe0aSwdenk		`${name}'; to execute the contents of a variable
22333b57fe0aSwdenk		directly type `$name' at the command prompt.
2234c609719bSwdenk
2235c609719bSwdenk		Global environment variables are those you use
2236c609719bSwdenk		setenv/printenv to work with. To run a command stored
2237c609719bSwdenk		in such a variable, you need to use the run command,
2238c609719bSwdenk		and you must not use the '$' sign to access them.
2239c609719bSwdenk
2240c609719bSwdenk		To store commands and special characters in a
2241c609719bSwdenk		variable, please use double quotation marks
2242c609719bSwdenk		surrounding the whole text of the variable, instead
2243c609719bSwdenk		of the backslashes before semicolons and special
2244c609719bSwdenk		symbols.
2245c609719bSwdenk
2246b445bbb4SJeremiah Mahler- Command Line Editing and History:
2247aa0c71acSWolfgang Denk		CONFIG_CMDLINE_EDITING
2248aa0c71acSWolfgang Denk
224911ccc33fSMarcel Ziswiler		Enable editing and History functions for interactive
2250aa0c71acSWolfgang Denk		command line input operations
2251aa0c71acSWolfgang Denk
2252f3b267b3SMarek Vasut- Command Line PS1/PS2 support:
2253f3b267b3SMarek Vasut		CONFIG_CMDLINE_PS_SUPPORT
2254f3b267b3SMarek Vasut
2255f3b267b3SMarek Vasut		Enable support for changing the command prompt string
2256f3b267b3SMarek Vasut		at run-time. Only static string is supported so far.
2257f3b267b3SMarek Vasut		The string is obtained from environment variables PS1
2258f3b267b3SMarek Vasut		and PS2.
2259f3b267b3SMarek Vasut
2260a8c7c708Swdenk- Default Environment:
2261c609719bSwdenk		CONFIG_EXTRA_ENV_SETTINGS
2262c609719bSwdenk
2263c609719bSwdenk		Define this to contain any number of null terminated
2264c609719bSwdenk		strings (variable = value pairs) that will be part of
22657152b1d0Swdenk		the default environment compiled into the boot image.
22662262cfeeSwdenk
2267c609719bSwdenk		For example, place something like this in your
2268c609719bSwdenk		board's config file:
2269c609719bSwdenk
2270c609719bSwdenk		#define CONFIG_EXTRA_ENV_SETTINGS \
2271c609719bSwdenk			"myvar1=value1\0" \
2272c609719bSwdenk			"myvar2=value2\0"
2273c609719bSwdenk
2274c609719bSwdenk		Warning: This method is based on knowledge about the
2275c609719bSwdenk		internal format how the environment is stored by the
22762262cfeeSwdenk		U-Boot code. This is NOT an official, exported
2277c609719bSwdenk		interface! Although it is unlikely that this format
22787152b1d0Swdenk		will change soon, there is no guarantee either.
2279c609719bSwdenk		You better know what you are doing here.
2280c609719bSwdenk
2281c609719bSwdenk		Note: overly (ab)use of the default environment is
2282c609719bSwdenk		discouraged. Make sure to check other ways to preset
228374de7aefSWolfgang Denk		the environment like the "source" command or the
2284c609719bSwdenk		boot command first.
2285c609719bSwdenk
22865e724ca2SStephen Warren		CONFIG_ENV_VARS_UBOOT_CONFIG
22875e724ca2SStephen Warren
22885e724ca2SStephen Warren		Define this in order to add variables describing the
22895e724ca2SStephen Warren		U-Boot build configuration to the default environment.
22905e724ca2SStephen Warren		These will be named arch, cpu, board, vendor, and soc.
22915e724ca2SStephen Warren
22925e724ca2SStephen Warren		Enabling this option will cause the following to be defined:
22935e724ca2SStephen Warren
22945e724ca2SStephen Warren		- CONFIG_SYS_ARCH
22955e724ca2SStephen Warren		- CONFIG_SYS_CPU
22965e724ca2SStephen Warren		- CONFIG_SYS_BOARD
22975e724ca2SStephen Warren		- CONFIG_SYS_VENDOR
22985e724ca2SStephen Warren		- CONFIG_SYS_SOC
22995e724ca2SStephen Warren
23007e27f89fSTom Rini		CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
23017e27f89fSTom Rini
23027e27f89fSTom Rini		Define this in order to add variables describing certain
23037e27f89fSTom Rini		run-time determined information about the hardware to the
23047e27f89fSTom Rini		environment.  These will be named board_name, board_rev.
23057e27f89fSTom Rini
230606fd8538SSimon Glass		CONFIG_DELAY_ENVIRONMENT
230706fd8538SSimon Glass
230806fd8538SSimon Glass		Normally the environment is loaded when the board is
2309b445bbb4SJeremiah Mahler		initialised so that it is available to U-Boot. This inhibits
231006fd8538SSimon Glass		that so that the environment is not available until
231106fd8538SSimon Glass		explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
231206fd8538SSimon Glass		this is instead controlled by the value of
231306fd8538SSimon Glass		/config/load-environment.
231406fd8538SSimon Glass
2315a8c7c708Swdenk- DataFlash Support:
23162abbe075Swdenk		CONFIG_HAS_DATAFLASH
23172abbe075Swdenk
23182abbe075Swdenk		Defining this option enables DataFlash features and
23192abbe075Swdenk		allows to read/write in Dataflash via the standard
23202abbe075Swdenk		commands cp, md...
23212abbe075Swdenk
2322f61ec45eSEric Nelson- Serial Flash support
232300fd59ddSSimon Glass		Usage requires an initial 'sf probe' to define the serial
2324f61ec45eSEric Nelson		flash parameters, followed by read/write/erase/update
2325f61ec45eSEric Nelson		commands.
2326f61ec45eSEric Nelson
2327f61ec45eSEric Nelson		The following defaults may be provided by the platform
2328f61ec45eSEric Nelson		to handle the common case when only a single serial
2329f61ec45eSEric Nelson		flash is present on the system.
2330f61ec45eSEric Nelson
2331f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_BUS		Bus identifier
2332f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_CS		Chip-select
2333f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_MODE 		(see include/spi.h)
2334f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_SPEED		in Hz
2335f61ec45eSEric Nelson
23363f85ce27Swdenk		CONFIG_SYSTEMACE
23373f85ce27Swdenk
23383f85ce27Swdenk		Adding this option adds support for Xilinx SystemACE
23393f85ce27Swdenk		chips attached via some sort of local bus. The address
234011ccc33fSMarcel Ziswiler		of the chip must also be defined in the
23416d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SYSTEMACE_BASE macro. For example:
23423f85ce27Swdenk
23433f85ce27Swdenk		#define CONFIG_SYSTEMACE
23446d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		#define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
23453f85ce27Swdenk
23463f85ce27Swdenk		When SystemACE support is added, the "ace" device type
23473f85ce27Swdenk		becomes available to the fat commands, i.e. fatls.
23483f85ce27Swdenk
2349ecb0ccd9SWolfgang Denk- TFTP Fixed UDP Port:
2350ecb0ccd9SWolfgang Denk		CONFIG_TFTP_PORT
2351ecb0ccd9SWolfgang Denk
235228cb9375SWolfgang Denk		If this is defined, the environment variable tftpsrcp
2353ecb0ccd9SWolfgang Denk		is used to supply the TFTP UDP source port value.
235428cb9375SWolfgang Denk		If tftpsrcp isn't defined, the normal pseudo-random port
2355ecb0ccd9SWolfgang Denk		number generator is used.
2356ecb0ccd9SWolfgang Denk
235728cb9375SWolfgang Denk		Also, the environment variable tftpdstp is used to supply
235828cb9375SWolfgang Denk		the TFTP UDP destination port value.  If tftpdstp isn't
235928cb9375SWolfgang Denk		defined, the normal port 69 is used.
236028cb9375SWolfgang Denk
236128cb9375SWolfgang Denk		The purpose for tftpsrcp is to allow a TFTP server to
2362ecb0ccd9SWolfgang Denk		blindly start the TFTP transfer using the pre-configured
2363ecb0ccd9SWolfgang Denk		target IP address and UDP port. This has the effect of
2364ecb0ccd9SWolfgang Denk		"punching through" the (Windows XP) firewall, allowing
2365ecb0ccd9SWolfgang Denk		the remainder of the TFTP transfer to proceed normally.
2366ecb0ccd9SWolfgang Denk		A better solution is to properly configure the firewall,
2367ecb0ccd9SWolfgang Denk		but sometimes that is not allowed.
2368ecb0ccd9SWolfgang Denk
23699e50c406SHeiko Schocher- bootcount support:
23709e50c406SHeiko Schocher		CONFIG_BOOTCOUNT_LIMIT
23719e50c406SHeiko Schocher
23729e50c406SHeiko Schocher		This enables the bootcounter support, see:
23739e50c406SHeiko Schocher		http://www.denx.de/wiki/DULG/UBootBootCountLimit
23749e50c406SHeiko Schocher
23759e50c406SHeiko Schocher		CONFIG_AT91SAM9XE
23769e50c406SHeiko Schocher		enable special bootcounter support on at91sam9xe based boards.
23779e50c406SHeiko Schocher		CONFIG_SOC_DA8XX
23789e50c406SHeiko Schocher		enable special bootcounter support on da850 based boards.
23799e50c406SHeiko Schocher		CONFIG_BOOTCOUNT_RAM
23809e50c406SHeiko Schocher		enable support for the bootcounter in RAM
23819e50c406SHeiko Schocher		CONFIG_BOOTCOUNT_I2C
23829e50c406SHeiko Schocher		enable support for the bootcounter on an i2c (like RTC) device.
23839e50c406SHeiko Schocher			CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
23849e50c406SHeiko Schocher			CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
23859e50c406SHeiko Schocher						    the bootcounter.
23869e50c406SHeiko Schocher			CONFIG_BOOTCOUNT_ALEN = address len
238719c402afSSimon Glass
2388a8c7c708Swdenk- Show boot progress:
2389c609719bSwdenk		CONFIG_SHOW_BOOT_PROGRESS
2390c609719bSwdenk
2391c609719bSwdenk		Defining this option allows to add some board-
2392c609719bSwdenk		specific code (calling a user-provided function
2393c609719bSwdenk		"show_boot_progress(int)") that enables you to show
2394c609719bSwdenk		the system's boot progress on some display (for
2395c609719bSwdenk		example, some LED's) on your board. At the moment,
2396c609719bSwdenk		the following checkpoints are implemented:
2397c609719bSwdenk
239894fd1316SSimon Glass
23991372cce2SMarian BalakowiczLegacy uImage format:
24001372cce2SMarian Balakowicz
2401c609719bSwdenk  Arg	Where			When
2402c609719bSwdenk    1	common/cmd_bootm.c	before attempting to boot an image
2403c609719bSwdenk   -1	common/cmd_bootm.c	Image header has bad	 magic number
2404c609719bSwdenk    2	common/cmd_bootm.c	Image header has correct magic number
2405c609719bSwdenk   -2	common/cmd_bootm.c	Image header has bad	 checksum
2406c609719bSwdenk    3	common/cmd_bootm.c	Image header has correct checksum
2407c609719bSwdenk   -3	common/cmd_bootm.c	Image data   has bad	 checksum
2408c609719bSwdenk    4	common/cmd_bootm.c	Image data   has correct checksum
2409c609719bSwdenk   -4	common/cmd_bootm.c	Image is for unsupported architecture
2410c609719bSwdenk    5	common/cmd_bootm.c	Architecture check OK
24111372cce2SMarian Balakowicz   -5	common/cmd_bootm.c	Wrong Image Type (not kernel, multi)
2412c609719bSwdenk    6	common/cmd_bootm.c	Image Type check OK
2413c609719bSwdenk   -6	common/cmd_bootm.c	gunzip uncompression error
2414c609719bSwdenk   -7	common/cmd_bootm.c	Unimplemented compression type
2415c609719bSwdenk    7	common/cmd_bootm.c	Uncompression OK
24161372cce2SMarian Balakowicz    8	common/cmd_bootm.c	No uncompress/copy overwrite error
2417c609719bSwdenk   -9	common/cmd_bootm.c	Unsupported OS (not Linux, BSD, VxWorks, QNX)
24181372cce2SMarian Balakowicz
24191372cce2SMarian Balakowicz    9	common/image.c		Start initial ramdisk verification
24201372cce2SMarian Balakowicz  -10	common/image.c		Ramdisk header has bad	   magic number
24211372cce2SMarian Balakowicz  -11	common/image.c		Ramdisk header has bad	   checksum
24221372cce2SMarian Balakowicz   10	common/image.c		Ramdisk header is OK
24231372cce2SMarian Balakowicz  -12	common/image.c		Ramdisk data   has bad	   checksum
24241372cce2SMarian Balakowicz   11	common/image.c		Ramdisk data   has correct checksum
24251372cce2SMarian Balakowicz   12	common/image.c		Ramdisk verification complete, start loading
242611ccc33fSMarcel Ziswiler  -13	common/image.c		Wrong Image Type (not PPC Linux ramdisk)
24271372cce2SMarian Balakowicz   13	common/image.c		Start multifile image verification
24281372cce2SMarian Balakowicz   14	common/image.c		No initial ramdisk, no multifile, continue.
24291372cce2SMarian Balakowicz
2430ea0364f1SPeter Tyser   15	arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2431c609719bSwdenk
2432a47a12beSStefan Roese  -30	arch/powerpc/lib/board.c	Fatal error, hang the system
243363e73c9aSwdenk  -31	post/post.c		POST test failed, detected by post_output_backlog()
243463e73c9aSwdenk  -32	post/post.c		POST test failed, detected by post_run_single()
243563e73c9aSwdenk
2436566a494fSHeiko Schocher   34	common/cmd_doc.c	before loading a Image from a DOC device
2437566a494fSHeiko Schocher  -35	common/cmd_doc.c	Bad usage of "doc" command
2438566a494fSHeiko Schocher   35	common/cmd_doc.c	correct usage of "doc" command
2439566a494fSHeiko Schocher  -36	common/cmd_doc.c	No boot device
2440566a494fSHeiko Schocher   36	common/cmd_doc.c	correct boot device
2441566a494fSHeiko Schocher  -37	common/cmd_doc.c	Unknown Chip ID on boot device
2442566a494fSHeiko Schocher   37	common/cmd_doc.c	correct chip ID found, device available
2443566a494fSHeiko Schocher  -38	common/cmd_doc.c	Read Error on boot device
2444566a494fSHeiko Schocher   38	common/cmd_doc.c	reading Image header from DOC device OK
2445566a494fSHeiko Schocher  -39	common/cmd_doc.c	Image header has bad magic number
2446566a494fSHeiko Schocher   39	common/cmd_doc.c	Image header has correct magic number
2447566a494fSHeiko Schocher  -40	common/cmd_doc.c	Error reading Image from DOC device
2448566a494fSHeiko Schocher   40	common/cmd_doc.c	Image header has correct magic number
2449566a494fSHeiko Schocher   41	common/cmd_ide.c	before loading a Image from a IDE device
2450566a494fSHeiko Schocher  -42	common/cmd_ide.c	Bad usage of "ide" command
2451566a494fSHeiko Schocher   42	common/cmd_ide.c	correct usage of "ide" command
2452566a494fSHeiko Schocher  -43	common/cmd_ide.c	No boot device
2453566a494fSHeiko Schocher   43	common/cmd_ide.c	boot device found
2454566a494fSHeiko Schocher  -44	common/cmd_ide.c	Device not available
2455566a494fSHeiko Schocher   44	common/cmd_ide.c	Device available
2456566a494fSHeiko Schocher  -45	common/cmd_ide.c	wrong partition selected
2457566a494fSHeiko Schocher   45	common/cmd_ide.c	partition selected
2458566a494fSHeiko Schocher  -46	common/cmd_ide.c	Unknown partition table
2459566a494fSHeiko Schocher   46	common/cmd_ide.c	valid partition table found
2460566a494fSHeiko Schocher  -47	common/cmd_ide.c	Invalid partition type
2461566a494fSHeiko Schocher   47	common/cmd_ide.c	correct partition type
2462566a494fSHeiko Schocher  -48	common/cmd_ide.c	Error reading Image Header on boot device
2463566a494fSHeiko Schocher   48	common/cmd_ide.c	reading Image Header from IDE device OK
2464566a494fSHeiko Schocher  -49	common/cmd_ide.c	Image header has bad magic number
2465566a494fSHeiko Schocher   49	common/cmd_ide.c	Image header has correct magic number
2466566a494fSHeiko Schocher  -50	common/cmd_ide.c	Image header has bad	 checksum
2467566a494fSHeiko Schocher   50	common/cmd_ide.c	Image header has correct checksum
2468566a494fSHeiko Schocher  -51	common/cmd_ide.c	Error reading Image from IDE device
2469566a494fSHeiko Schocher   51	common/cmd_ide.c	reading Image from IDE device OK
2470566a494fSHeiko Schocher   52	common/cmd_nand.c	before loading a Image from a NAND device
2471566a494fSHeiko Schocher  -53	common/cmd_nand.c	Bad usage of "nand" command
2472566a494fSHeiko Schocher   53	common/cmd_nand.c	correct usage of "nand" command
2473566a494fSHeiko Schocher  -54	common/cmd_nand.c	No boot device
2474566a494fSHeiko Schocher   54	common/cmd_nand.c	boot device found
2475566a494fSHeiko Schocher  -55	common/cmd_nand.c	Unknown Chip ID on boot device
2476566a494fSHeiko Schocher   55	common/cmd_nand.c	correct chip ID found, device available
2477566a494fSHeiko Schocher  -56	common/cmd_nand.c	Error reading Image Header on boot device
2478566a494fSHeiko Schocher   56	common/cmd_nand.c	reading Image Header from NAND device OK
2479566a494fSHeiko Schocher  -57	common/cmd_nand.c	Image header has bad magic number
2480566a494fSHeiko Schocher   57	common/cmd_nand.c	Image header has correct magic number
2481566a494fSHeiko Schocher  -58	common/cmd_nand.c	Error reading Image from NAND device
2482566a494fSHeiko Schocher   58	common/cmd_nand.c	reading Image from NAND device OK
2483c609719bSwdenk
2484566a494fSHeiko Schocher  -60	common/env_common.c	Environment has a bad CRC, using default
2485c609719bSwdenk
2486566a494fSHeiko Schocher   64	net/eth.c		starting with Ethernet configuration.
2487566a494fSHeiko Schocher  -64	net/eth.c		no Ethernet found.
2488566a494fSHeiko Schocher   65	net/eth.c		Ethernet found.
2489206c60cbSwdenk
2490566a494fSHeiko Schocher  -80	common/cmd_net.c	usage wrong
2491bc0571fcSJoe Hershberger   80	common/cmd_net.c	before calling net_loop()
2492bc0571fcSJoe Hershberger  -81	common/cmd_net.c	some error in net_loop() occurred
2493bc0571fcSJoe Hershberger   81	common/cmd_net.c	net_loop() back without error
2494566a494fSHeiko Schocher  -82	common/cmd_net.c	size == 0 (File with size 0 loaded)
2495566a494fSHeiko Schocher   82	common/cmd_net.c	trying automatic boot
249674de7aefSWolfgang Denk   83	common/cmd_net.c	running "source" command
249774de7aefSWolfgang Denk  -83	common/cmd_net.c	some error in automatic boot or "source" command
2498566a494fSHeiko Schocher   84	common/cmd_net.c	end without errors
2499c609719bSwdenk
25001372cce2SMarian BalakowiczFIT uImage format:
25011372cce2SMarian Balakowicz
25021372cce2SMarian Balakowicz  Arg	Where			When
25031372cce2SMarian Balakowicz  100	common/cmd_bootm.c	Kernel FIT Image has correct format
25041372cce2SMarian Balakowicz -100	common/cmd_bootm.c	Kernel FIT Image has incorrect format
25051372cce2SMarian Balakowicz  101	common/cmd_bootm.c	No Kernel subimage unit name, using configuration
25061372cce2SMarian Balakowicz -101	common/cmd_bootm.c	Can't get configuration for kernel subimage
25071372cce2SMarian Balakowicz  102	common/cmd_bootm.c	Kernel unit name specified
25081372cce2SMarian Balakowicz -103	common/cmd_bootm.c	Can't get kernel subimage node offset
2509f773bea8SMarian Balakowicz  103	common/cmd_bootm.c	Found configuration node
25101372cce2SMarian Balakowicz  104	common/cmd_bootm.c	Got kernel subimage node offset
25111372cce2SMarian Balakowicz -104	common/cmd_bootm.c	Kernel subimage hash verification failed
25121372cce2SMarian Balakowicz  105	common/cmd_bootm.c	Kernel subimage hash verification OK
25131372cce2SMarian Balakowicz -105	common/cmd_bootm.c	Kernel subimage is for unsupported architecture
25141372cce2SMarian Balakowicz  106	common/cmd_bootm.c	Architecture check OK
251511ccc33fSMarcel Ziswiler -106	common/cmd_bootm.c	Kernel subimage has wrong type
251611ccc33fSMarcel Ziswiler  107	common/cmd_bootm.c	Kernel subimage type OK
25171372cce2SMarian Balakowicz -107	common/cmd_bootm.c	Can't get kernel subimage data/size
25181372cce2SMarian Balakowicz  108	common/cmd_bootm.c	Got kernel subimage data/size
25191372cce2SMarian Balakowicz -108	common/cmd_bootm.c	Wrong image type (not legacy, FIT)
25201372cce2SMarian Balakowicz -109	common/cmd_bootm.c	Can't get kernel subimage type
25211372cce2SMarian Balakowicz -110	common/cmd_bootm.c	Can't get kernel subimage comp
25221372cce2SMarian Balakowicz -111	common/cmd_bootm.c	Can't get kernel subimage os
25231372cce2SMarian Balakowicz -112	common/cmd_bootm.c	Can't get kernel subimage load address
25241372cce2SMarian Balakowicz -113	common/cmd_bootm.c	Image uncompress/copy overwrite error
25251372cce2SMarian Balakowicz
25261372cce2SMarian Balakowicz  120	common/image.c		Start initial ramdisk verification
25271372cce2SMarian Balakowicz -120	common/image.c		Ramdisk FIT image has incorrect format
25281372cce2SMarian Balakowicz  121	common/image.c		Ramdisk FIT image has correct format
252911ccc33fSMarcel Ziswiler  122	common/image.c		No ramdisk subimage unit name, using configuration
25301372cce2SMarian Balakowicz -122	common/image.c		Can't get configuration for ramdisk subimage
25311372cce2SMarian Balakowicz  123	common/image.c		Ramdisk unit name specified
25321372cce2SMarian Balakowicz -124	common/image.c		Can't get ramdisk subimage node offset
25331372cce2SMarian Balakowicz  125	common/image.c		Got ramdisk subimage node offset
25341372cce2SMarian Balakowicz -125	common/image.c		Ramdisk subimage hash verification failed
25351372cce2SMarian Balakowicz  126	common/image.c		Ramdisk subimage hash verification OK
25361372cce2SMarian Balakowicz -126	common/image.c		Ramdisk subimage for unsupported architecture
25371372cce2SMarian Balakowicz  127	common/image.c		Architecture check OK
25381372cce2SMarian Balakowicz -127	common/image.c		Can't get ramdisk subimage data/size
25391372cce2SMarian Balakowicz  128	common/image.c		Got ramdisk subimage data/size
25401372cce2SMarian Balakowicz  129	common/image.c		Can't get ramdisk load address
25411372cce2SMarian Balakowicz -129	common/image.c		Got ramdisk load address
25421372cce2SMarian Balakowicz
254311ccc33fSMarcel Ziswiler -130	common/cmd_doc.c	Incorrect FIT image format
25441372cce2SMarian Balakowicz  131	common/cmd_doc.c	FIT image format OK
25451372cce2SMarian Balakowicz
254611ccc33fSMarcel Ziswiler -140	common/cmd_ide.c	Incorrect FIT image format
25471372cce2SMarian Balakowicz  141	common/cmd_ide.c	FIT image format OK
25481372cce2SMarian Balakowicz
254911ccc33fSMarcel Ziswiler -150	common/cmd_nand.c	Incorrect FIT image format
25501372cce2SMarian Balakowicz  151	common/cmd_nand.c	FIT image format OK
25511372cce2SMarian Balakowicz
255221d29f7fSHeiko Schocher- legacy image format:
255321d29f7fSHeiko Schocher		CONFIG_IMAGE_FORMAT_LEGACY
255421d29f7fSHeiko Schocher		enables the legacy image format support in U-Boot.
255521d29f7fSHeiko Schocher
255621d29f7fSHeiko Schocher		Default:
255721d29f7fSHeiko Schocher		enabled if CONFIG_FIT_SIGNATURE is not defined.
255821d29f7fSHeiko Schocher
255921d29f7fSHeiko Schocher		CONFIG_DISABLE_IMAGE_LEGACY
256021d29f7fSHeiko Schocher		disable the legacy image format
256121d29f7fSHeiko Schocher
256221d29f7fSHeiko Schocher		This define is introduced, as the legacy image format is
256321d29f7fSHeiko Schocher		enabled per default for backward compatibility.
256421d29f7fSHeiko Schocher
25654cf2609bSWolfgang Denk- Standalone program support:
25664cf2609bSWolfgang Denk		CONFIG_STANDALONE_LOAD_ADDR
25674cf2609bSWolfgang Denk
25686feff899SWolfgang Denk		This option defines a board specific value for the
25696feff899SWolfgang Denk		address where standalone program gets loaded, thus
25706feff899SWolfgang Denk		overwriting the architecture dependent default
25714cf2609bSWolfgang Denk		settings.
25724cf2609bSWolfgang Denk
25734cf2609bSWolfgang Denk- Frame Buffer Address:
25744cf2609bSWolfgang Denk		CONFIG_FB_ADDR
25754cf2609bSWolfgang Denk
25764cf2609bSWolfgang Denk		Define CONFIG_FB_ADDR if you want to use specific
257744a53b57SWolfgang Denk		address for frame buffer.  This is typically the case
257844a53b57SWolfgang Denk		when using a graphics controller has separate video
257944a53b57SWolfgang Denk		memory.  U-Boot will then place the frame buffer at
258044a53b57SWolfgang Denk		the given address instead of dynamically reserving it
258144a53b57SWolfgang Denk		in system RAM by calling lcd_setmem(), which grabs
258244a53b57SWolfgang Denk		the memory for the frame buffer depending on the
258344a53b57SWolfgang Denk		configured panel size.
25844cf2609bSWolfgang Denk
25854cf2609bSWolfgang Denk		Please see board_init_f function.
25864cf2609bSWolfgang Denk
2587cccfc2abSDetlev Zundel- Automatic software updates via TFTP server
2588cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP
2589cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP_CNT_MAX
2590cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP_MSEC_MAX
2591cccfc2abSDetlev Zundel
2592cccfc2abSDetlev Zundel		These options enable and control the auto-update feature;
2593cccfc2abSDetlev Zundel		for a more detailed description refer to doc/README.update.
2594cccfc2abSDetlev Zundel
2595cccfc2abSDetlev Zundel- MTD Support (mtdparts command, UBI support)
2596cccfc2abSDetlev Zundel		CONFIG_MTD_DEVICE
2597cccfc2abSDetlev Zundel
2598cccfc2abSDetlev Zundel		Adds the MTD device infrastructure from the Linux kernel.
2599cccfc2abSDetlev Zundel		Needed for mtdparts command support.
2600cccfc2abSDetlev Zundel
2601cccfc2abSDetlev Zundel		CONFIG_MTD_PARTITIONS
2602cccfc2abSDetlev Zundel
2603cccfc2abSDetlev Zundel		Adds the MTD partitioning infrastructure from the Linux
2604cccfc2abSDetlev Zundel		kernel. Needed for UBI support.
2605cccfc2abSDetlev Zundel
260670c219cdSJoe Hershberger- UBI support
2607147162daSJoe Hershberger		CONFIG_UBI_SILENCE_MSG
2608147162daSJoe Hershberger
2609147162daSJoe Hershberger		Make the verbose messages from UBI stop printing.  This leaves
2610147162daSJoe Hershberger		warnings and errors enabled.
2611147162daSJoe Hershberger
2612ff94bc40SHeiko Schocher
2613ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_WL_THRESHOLD
2614ff94bc40SHeiko Schocher		This parameter defines the maximum difference between the highest
2615ff94bc40SHeiko Schocher		erase counter value and the lowest erase counter value of eraseblocks
2616ff94bc40SHeiko Schocher		of UBI devices. When this threshold is exceeded, UBI starts performing
2617ff94bc40SHeiko Schocher		wear leveling by means of moving data from eraseblock with low erase
2618ff94bc40SHeiko Schocher		counter to eraseblocks with high erase counter.
2619ff94bc40SHeiko Schocher
2620ff94bc40SHeiko Schocher		The default value should be OK for SLC NAND flashes, NOR flashes and
2621ff94bc40SHeiko Schocher		other flashes which have eraseblock life-cycle 100000 or more.
2622ff94bc40SHeiko Schocher		However, in case of MLC NAND flashes which typically have eraseblock
2623ff94bc40SHeiko Schocher		life-cycle less than 10000, the threshold should be lessened (e.g.,
2624ff94bc40SHeiko Schocher		to 128 or 256, although it does not have to be power of 2).
2625ff94bc40SHeiko Schocher
2626ff94bc40SHeiko Schocher		default: 4096
2627ff94bc40SHeiko Schocher
2628ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_BEB_LIMIT
2629ff94bc40SHeiko Schocher		This option specifies the maximum bad physical eraseblocks UBI
2630ff94bc40SHeiko Schocher		expects on the MTD device (per 1024 eraseblocks). If the
2631ff94bc40SHeiko Schocher		underlying flash does not admit of bad eraseblocks (e.g. NOR
2632ff94bc40SHeiko Schocher		flash), this value is ignored.
2633ff94bc40SHeiko Schocher
2634ff94bc40SHeiko Schocher		NAND datasheets often specify the minimum and maximum NVM
2635ff94bc40SHeiko Schocher		(Number of Valid Blocks) for the flashes' endurance lifetime.
2636ff94bc40SHeiko Schocher		The maximum expected bad eraseblocks per 1024 eraseblocks
2637ff94bc40SHeiko Schocher		then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2638ff94bc40SHeiko Schocher		which gives 20 for most NANDs (MaxNVB is basically the total
2639ff94bc40SHeiko Schocher		count of eraseblocks on the chip).
2640ff94bc40SHeiko Schocher
2641ff94bc40SHeiko Schocher		To put it differently, if this value is 20, UBI will try to
2642ff94bc40SHeiko Schocher		reserve about 1.9% of physical eraseblocks for bad blocks
2643ff94bc40SHeiko Schocher		handling. And that will be 1.9% of eraseblocks on the entire
2644ff94bc40SHeiko Schocher		NAND chip, not just the MTD partition UBI attaches. This means
2645ff94bc40SHeiko Schocher		that if you have, say, a NAND flash chip admits maximum 40 bad
2646ff94bc40SHeiko Schocher		eraseblocks, and it is split on two MTD partitions of the same
2647ff94bc40SHeiko Schocher		size, UBI will reserve 40 eraseblocks when attaching a
2648ff94bc40SHeiko Schocher		partition.
2649ff94bc40SHeiko Schocher
2650ff94bc40SHeiko Schocher		default: 20
2651ff94bc40SHeiko Schocher
2652ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_FASTMAP
2653ff94bc40SHeiko Schocher		Fastmap is a mechanism which allows attaching an UBI device
2654ff94bc40SHeiko Schocher		in nearly constant time. Instead of scanning the whole MTD device it
2655ff94bc40SHeiko Schocher		only has to locate a checkpoint (called fastmap) on the device.
2656ff94bc40SHeiko Schocher		The on-flash fastmap contains all information needed to attach
2657ff94bc40SHeiko Schocher		the device. Using fastmap makes only sense on large devices where
2658ff94bc40SHeiko Schocher		attaching by scanning takes long. UBI will not automatically install
2659ff94bc40SHeiko Schocher		a fastmap on old images, but you can set the UBI parameter
2660ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2661ff94bc40SHeiko Schocher		that fastmap-enabled images are still usable with UBI implementations
2662ff94bc40SHeiko Schocher		without	fastmap support. On typical flash devices the whole fastmap
2663ff94bc40SHeiko Schocher		fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2664ff94bc40SHeiko Schocher
2665ff94bc40SHeiko Schocher		CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2666ff94bc40SHeiko Schocher		Set this parameter to enable fastmap automatically on images
2667ff94bc40SHeiko Schocher		without a fastmap.
2668ff94bc40SHeiko Schocher		default: 0
2669ff94bc40SHeiko Schocher
26700195a7bbSHeiko Schocher		CONFIG_MTD_UBI_FM_DEBUG
26710195a7bbSHeiko Schocher		Enable UBI fastmap debug
26720195a7bbSHeiko Schocher		default: 0
26730195a7bbSHeiko Schocher
267470c219cdSJoe Hershberger- UBIFS support
2675147162daSJoe Hershberger		CONFIG_UBIFS_SILENCE_MSG
2676147162daSJoe Hershberger
2677147162daSJoe Hershberger		Make the verbose messages from UBIFS stop printing.  This leaves
2678147162daSJoe Hershberger		warnings and errors enabled.
2679147162daSJoe Hershberger
26806a11cf48SDaniel Schwierzeck- SPL framework
26816a11cf48SDaniel Schwierzeck		CONFIG_SPL
26826a11cf48SDaniel Schwierzeck		Enable building of SPL globally.
26836a11cf48SDaniel Schwierzeck
268495579793STom Rini		CONFIG_SPL_LDSCRIPT
268595579793STom Rini		LDSCRIPT for linking the SPL binary.
268695579793STom Rini
26876ebc3461SAlbert ARIBAUD		CONFIG_SPL_MAX_FOOTPRINT
26886ebc3461SAlbert ARIBAUD		Maximum size in memory allocated to the SPL, BSS included.
26896ebc3461SAlbert ARIBAUD		When defined, the linker checks that the actual memory
26906ebc3461SAlbert ARIBAUD		used by SPL from _start to __bss_end does not exceed it.
26918960af8bSAlbert ARIBAUD		CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
26926ebc3461SAlbert ARIBAUD		must not be both defined at the same time.
26936ebc3461SAlbert ARIBAUD
269495579793STom Rini		CONFIG_SPL_MAX_SIZE
26956ebc3461SAlbert ARIBAUD		Maximum size of the SPL image (text, data, rodata, and
26966ebc3461SAlbert ARIBAUD		linker lists sections), BSS excluded.
26976ebc3461SAlbert ARIBAUD		When defined, the linker checks that the actual size does
26986ebc3461SAlbert ARIBAUD		not exceed it.
269995579793STom Rini
27006a11cf48SDaniel Schwierzeck		CONFIG_SPL_TEXT_BASE
27016a11cf48SDaniel Schwierzeck		TEXT_BASE for linking the SPL binary.
27026a11cf48SDaniel Schwierzeck
270394a45bb1SScott Wood		CONFIG_SPL_RELOC_TEXT_BASE
270494a45bb1SScott Wood		Address to relocate to.  If unspecified, this is equal to
270594a45bb1SScott Wood		CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
270694a45bb1SScott Wood
270795579793STom Rini		CONFIG_SPL_BSS_START_ADDR
270895579793STom Rini		Link address for the BSS within the SPL binary.
270995579793STom Rini
271095579793STom Rini		CONFIG_SPL_BSS_MAX_SIZE
27116ebc3461SAlbert ARIBAUD		Maximum size in memory allocated to the SPL BSS.
27126ebc3461SAlbert ARIBAUD		When defined, the linker checks that the actual memory used
27136ebc3461SAlbert ARIBAUD		by SPL from __bss_start to __bss_end does not exceed it.
27148960af8bSAlbert ARIBAUD		CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
27156ebc3461SAlbert ARIBAUD		must not be both defined at the same time.
271695579793STom Rini
271795579793STom Rini		CONFIG_SPL_STACK
271895579793STom Rini		Adress of the start of the stack SPL will use
271995579793STom Rini
27208c80eb3bSAlbert ARIBAUD \(3ADEV\)		CONFIG_SPL_PANIC_ON_RAW_IMAGE
27218c80eb3bSAlbert ARIBAUD \(3ADEV\)		When defined, SPL will panic() if the image it has
27228c80eb3bSAlbert ARIBAUD \(3ADEV\)		loaded does not have a signature.
27238c80eb3bSAlbert ARIBAUD \(3ADEV\)		Defining this is useful when code which loads images
27248c80eb3bSAlbert ARIBAUD \(3ADEV\)		in SPL cannot guarantee that absolutely all read errors
27258c80eb3bSAlbert ARIBAUD \(3ADEV\)		will be caught.
27268c80eb3bSAlbert ARIBAUD \(3ADEV\)		An example is the LPC32XX MLC NAND driver, which will
27278c80eb3bSAlbert ARIBAUD \(3ADEV\)		consider that a completely unreadable NAND block is bad,
27288c80eb3bSAlbert ARIBAUD \(3ADEV\)		and thus should be skipped silently.
27298c80eb3bSAlbert ARIBAUD \(3ADEV\)
273094a45bb1SScott Wood		CONFIG_SPL_RELOC_STACK
273194a45bb1SScott Wood		Adress of the start of the stack SPL will use after
273294a45bb1SScott Wood		relocation.  If unspecified, this is equal to
273394a45bb1SScott Wood		CONFIG_SPL_STACK.
273494a45bb1SScott Wood
273595579793STom Rini		CONFIG_SYS_SPL_MALLOC_START
273695579793STom Rini		Starting address of the malloc pool used in SPL.
27379ac4fc82SFabio Estevam		When this option is set the full malloc is used in SPL and
27389ac4fc82SFabio Estevam		it is set up by spl_init() and before that, the simple malloc()
27399ac4fc82SFabio Estevam		can be used if CONFIG_SYS_MALLOC_F is defined.
274095579793STom Rini
274195579793STom Rini		CONFIG_SYS_SPL_MALLOC_SIZE
274295579793STom Rini		The size of the malloc pool used in SPL.
27436a11cf48SDaniel Schwierzeck
274447f7bcaeSTom Rini		CONFIG_SPL_FRAMEWORK
274547f7bcaeSTom Rini		Enable the SPL framework under common/.  This framework
274647f7bcaeSTom Rini		supports MMC, NAND and YMODEM loading of U-Boot and NAND
274747f7bcaeSTom Rini		NAND loading of the Linux Kernel.
274847f7bcaeSTom Rini
27499607faf2STom Rini		CONFIG_SPL_OS_BOOT
27509607faf2STom Rini		Enable booting directly to an OS from SPL.
27519607faf2STom Rini		See also: doc/README.falcon
27529607faf2STom Rini
2753861a86f4STom Rini		CONFIG_SPL_DISPLAY_PRINT
2754861a86f4STom Rini		For ARM, enable an optional function to print more information
2755861a86f4STom Rini		about the running system.
2756861a86f4STom Rini
27574b919725SScott Wood		CONFIG_SPL_INIT_MINIMAL
27584b919725SScott Wood		Arch init code should be built for a very small image
27594b919725SScott Wood
2760b97300b6SPaul Kocialkowski		CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2761b97300b6SPaul Kocialkowski		Partition on the MMC to load U-Boot from when the MMC is being
2762b97300b6SPaul Kocialkowski		used in raw mode
2763b97300b6SPaul Kocialkowski
27642b75b0adSPeter Korsgaard		CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
27652b75b0adSPeter Korsgaard		Sector to load kernel uImage from when MMC is being
27662b75b0adSPeter Korsgaard		used in raw mode (for Falcon mode)
27672b75b0adSPeter Korsgaard
27682b75b0adSPeter Korsgaard		CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
27692b75b0adSPeter Korsgaard		CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
27702b75b0adSPeter Korsgaard		Sector and number of sectors to load kernel argument
27712b75b0adSPeter Korsgaard		parameters from when MMC is being used in raw mode
27722b75b0adSPeter Korsgaard		(for falcon mode)
27732b75b0adSPeter Korsgaard
2774e2ccdf89SPaul Kocialkowski		CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2775e2ccdf89SPaul Kocialkowski		Partition on the MMC to load U-Boot from when the MMC is being
2776e2ccdf89SPaul Kocialkowski		used in fs mode
2777e2ccdf89SPaul Kocialkowski
2778fae81c72SGuillaume GARDET		CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2779fae81c72SGuillaume GARDET		Filename to read to load U-Boot when reading from filesystem
2780fae81c72SGuillaume GARDET
2781fae81c72SGuillaume GARDET		CONFIG_SPL_FS_LOAD_KERNEL_NAME
27827ad2cc79SPeter Korsgaard		Filename to read to load kernel uImage when reading
2783fae81c72SGuillaume GARDET		from filesystem (for Falcon mode)
27847ad2cc79SPeter Korsgaard
2785fae81c72SGuillaume GARDET		CONFIG_SPL_FS_LOAD_ARGS_NAME
27867ad2cc79SPeter Korsgaard		Filename to read to load kernel argument parameters
2787fae81c72SGuillaume GARDET		when reading from filesystem (for Falcon mode)
27887ad2cc79SPeter Korsgaard
278906f60ae3SScott Wood		CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
279006f60ae3SScott Wood		Set this for NAND SPL on PPC mpc83xx targets, so that
279106f60ae3SScott Wood		start.S waits for the rest of the SPL to load before
279206f60ae3SScott Wood		continuing (the hardware starts execution after just
279306f60ae3SScott Wood		loading the first page rather than the full 4K).
279406f60ae3SScott Wood
2795651fcf60SPrabhakar Kushwaha		CONFIG_SPL_SKIP_RELOCATE
2796651fcf60SPrabhakar Kushwaha		Avoid SPL relocation
2797651fcf60SPrabhakar Kushwaha
27986f2f01b9SScott Wood		CONFIG_SPL_NAND_BASE
27996f2f01b9SScott Wood		Include nand_base.c in the SPL.  Requires
28006f2f01b9SScott Wood		CONFIG_SPL_NAND_DRIVERS.
28016f2f01b9SScott Wood
28026f2f01b9SScott Wood		CONFIG_SPL_NAND_DRIVERS
28036f2f01b9SScott Wood		SPL uses normal NAND drivers, not minimal drivers.
28046f2f01b9SScott Wood
28056f2f01b9SScott Wood		CONFIG_SPL_NAND_ECC
28066f2f01b9SScott Wood		Include standard software ECC in the SPL
28076f2f01b9SScott Wood
280895579793STom Rini		CONFIG_SPL_NAND_SIMPLE
28097d4b7955SScott Wood		Support for NAND boot using simple NAND drivers that
28107d4b7955SScott Wood		expose the cmd_ctrl() interface.
281195579793STom Rini
28126f4e7d3cSThomas Gleixner		CONFIG_SPL_UBI
28136f4e7d3cSThomas Gleixner		Support for a lightweight UBI (fastmap) scanner and
28146f4e7d3cSThomas Gleixner		loader
28156f4e7d3cSThomas Gleixner
28160c3117b1SHeiko Schocher		CONFIG_SPL_NAND_RAW_ONLY
28170c3117b1SHeiko Schocher		Support to boot only raw u-boot.bin images. Use this only
28180c3117b1SHeiko Schocher		if you need to save space.
28190c3117b1SHeiko Schocher
28207c8eea59SYing Zhang		CONFIG_SPL_COMMON_INIT_DDR
28217c8eea59SYing Zhang		Set for common ddr init with serial presence detect in
28227c8eea59SYing Zhang		SPL binary.
28237c8eea59SYing Zhang
282495579793STom Rini		CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
282595579793STom Rini		CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
282695579793STom Rini		CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
282795579793STom Rini		CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
282895579793STom Rini		CONFIG_SYS_NAND_ECCBYTES
282995579793STom Rini		Defines the size and behavior of the NAND that SPL uses
28307d4b7955SScott Wood		to read U-Boot
283195579793STom Rini
2832fbe76ae4SPrabhakar Kushwaha		CONFIG_SPL_NAND_BOOT
2833fbe76ae4SPrabhakar Kushwaha		Add support NAND boot
2834fbe76ae4SPrabhakar Kushwaha
283595579793STom Rini		CONFIG_SYS_NAND_U_BOOT_OFFS
28367d4b7955SScott Wood		Location in NAND to read U-Boot from
28377d4b7955SScott Wood
28387d4b7955SScott Wood		CONFIG_SYS_NAND_U_BOOT_DST
28397d4b7955SScott Wood		Location in memory to load U-Boot to
28407d4b7955SScott Wood
28417d4b7955SScott Wood		CONFIG_SYS_NAND_U_BOOT_SIZE
28427d4b7955SScott Wood		Size of image to load
284395579793STom Rini
284495579793STom Rini		CONFIG_SYS_NAND_U_BOOT_START
28457d4b7955SScott Wood		Entry point in loaded image to jump to
284695579793STom Rini
284795579793STom Rini		CONFIG_SYS_NAND_HW_ECC_OOBFIRST
284895579793STom Rini		Define this if you need to first read the OOB and then the
2849b445bbb4SJeremiah Mahler		data. This is used, for example, on davinci platforms.
285095579793STom Rini
2851c57b953dSPavel Machek		CONFIG_SPL_RAM_DEVICE
2852c57b953dSPavel Machek		Support for running image already present in ram, in SPL binary
2853c57b953dSPavel Machek
285474752baaSScott Wood		CONFIG_SPL_PAD_TO
28556113d3f2SBenoît Thébaudeau		Image offset to which the SPL should be padded before appending
28566113d3f2SBenoît Thébaudeau		the SPL payload. By default, this is defined as
28576113d3f2SBenoît Thébaudeau		CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
28586113d3f2SBenoît Thébaudeau		CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
28596113d3f2SBenoît Thébaudeau		payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
286074752baaSScott Wood
2861ca2fca22SScott Wood		CONFIG_SPL_TARGET
2862ca2fca22SScott Wood		Final target image containing SPL and payload.  Some SPLs
2863ca2fca22SScott Wood		use an arch-specific makefile fragment instead, for
2864ca2fca22SScott Wood		example if more than one image needs to be produced.
2865ca2fca22SScott Wood
286687ebee39SSimon Glass		CONFIG_FIT_SPL_PRINT
286787ebee39SSimon Glass		Printing information about a FIT image adds quite a bit of
286887ebee39SSimon Glass		code to SPL. So this is normally disabled in SPL. Use this
286987ebee39SSimon Glass		option to re-enable it. This will affect the output of the
287087ebee39SSimon Glass		bootm command when booting a FIT image.
287187ebee39SSimon Glass
28723aa29de0SYing Zhang- TPL framework
28733aa29de0SYing Zhang		CONFIG_TPL
28743aa29de0SYing Zhang		Enable building of TPL globally.
28753aa29de0SYing Zhang
28763aa29de0SYing Zhang		CONFIG_TPL_PAD_TO
28773aa29de0SYing Zhang		Image offset to which the TPL should be padded before appending
28783aa29de0SYing Zhang		the TPL payload. By default, this is defined as
28793aa29de0SYing Zhang		CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
28803aa29de0SYing Zhang		CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
28813aa29de0SYing Zhang		payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
28823aa29de0SYing Zhang
2883a8c7c708Swdenk- Interrupt support (PPC):
2884a8c7c708Swdenk
2885a8c7c708Swdenk		There are common interrupt_init() and timer_interrupt()
2886a8c7c708Swdenk		for all PPC archs. interrupt_init() calls interrupt_init_cpu()
288711ccc33fSMarcel Ziswiler		for CPU specific initialization. interrupt_init_cpu()
2888a8c7c708Swdenk		should set decrementer_count to appropriate value. If
288911ccc33fSMarcel Ziswiler		CPU resets decrementer automatically after interrupt
2890a8c7c708Swdenk		(ppc4xx) it should set decrementer_count to zero.
289111ccc33fSMarcel Ziswiler		timer_interrupt() calls timer_interrupt_cpu() for CPU
2892a8c7c708Swdenk		specific handling. If board has watchdog / status_led
2893a8c7c708Swdenk		/ other_activity_monitor it works automatically from
2894a8c7c708Swdenk		general timer_interrupt().
2895a8c7c708Swdenk
2896c609719bSwdenk
28979660e442SHelmut RaigerBoard initialization settings:
28989660e442SHelmut Raiger------------------------------
28999660e442SHelmut Raiger
29009660e442SHelmut RaigerDuring Initialization u-boot calls a number of board specific functions
29019660e442SHelmut Raigerto allow the preparation of board specific prerequisites, e.g. pin setup
29029660e442SHelmut Raigerbefore drivers are initialized. To enable these callbacks the
29039660e442SHelmut Raigerfollowing configuration macros have to be defined. Currently this is
29049660e442SHelmut Raigerarchitecture specific, so please check arch/your_architecture/lib/board.c
29059660e442SHelmut Raigertypically in board_init_f() and board_init_r().
29069660e442SHelmut Raiger
29079660e442SHelmut Raiger- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
29089660e442SHelmut Raiger- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
29099660e442SHelmut Raiger- CONFIG_BOARD_LATE_INIT: Call board_late_init()
29109660e442SHelmut Raiger- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
2911c609719bSwdenk
2912c609719bSwdenkConfiguration Settings:
2913c609719bSwdenk-----------------------
2914c609719bSwdenk
29154d1fd7f1SYork Sun- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
29164d1fd7f1SYork Sun		Optionally it can be defined to support 64-bit memory commands.
29174d1fd7f1SYork Sun
29186d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2919c609719bSwdenk		undefine this when you're short of memory.
2920c609719bSwdenk
29212fb2604dSPeter Tyser- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
29222fb2604dSPeter Tyser		width of the commands listed in the 'help' command output.
29232fb2604dSPeter Tyser
29246d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PROMPT:	This is what U-Boot prints on the console to
2925c609719bSwdenk		prompt for user input.
2926c609719bSwdenk
29276d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CBSIZE:	Buffer size for input from the Console
2928c609719bSwdenk
29296d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PBSIZE:	Buffer size for Console output
2930c609719bSwdenk
29316d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAXARGS:	max. Number of arguments accepted for monitor commands
2932c609719bSwdenk
29336d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2934c609719bSwdenk		the application (usually a Linux kernel) when it is
2935c609719bSwdenk		booted
2936c609719bSwdenk
29376d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BAUDRATE_TABLE:
2938c609719bSwdenk		List of legal baudrate settings for this board.
2939c609719bSwdenk
29406d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2941c609719bSwdenk		Begin and End addresses of the area used by the
2942c609719bSwdenk		simple memory test.
2943c609719bSwdenk
29446d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_ALT_MEMTEST:
2945c609719bSwdenk		Enable an alternate, more extensive memory test.
2946c609719bSwdenk
29476d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MEMTEST_SCRATCH:
29485f535fe1Swdenk		Scratch address used by the alternate memory test
29495f535fe1Swdenk		You only need to set this if address zero isn't writeable
29505f535fe1Swdenk
2951e8149522SYork Sun- CONFIG_SYS_MEM_RESERVE_SECURE
2952e61a7534SYork Sun		Only implemented for ARMv8 for now.
2953e8149522SYork Sun		If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2954e8149522SYork Sun		is substracted from total RAM and won't be reported to OS.
2955e8149522SYork Sun		This memory can be used as secure memory. A variable
2956e61a7534SYork Sun		gd->arch.secure_ram is used to track the location. In systems
2957e8149522SYork Sun		the RAM base is not zero, or RAM is divided into banks,
2958e8149522SYork Sun		this variable needs to be recalcuated to get the address.
2959e8149522SYork Sun
2960aabd7ddbSYork Sun- CONFIG_SYS_MEM_TOP_HIDE:
29616d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
296214f73ca6SStefan Roese		this specified memory area will get subtracted from the top
296311ccc33fSMarcel Ziswiler		(end) of RAM and won't get "touched" at all by U-Boot. By
296414f73ca6SStefan Roese		fixing up gd->ram_size the Linux kernel should gets passed
296514f73ca6SStefan Roese		the now "corrected" memory size and won't touch it either.
296614f73ca6SStefan Roese		This should work for arch/ppc and arch/powerpc. Only Linux
29675e12e75dSStefan Roese		board ports in arch/powerpc with bootwrapper support that
296814f73ca6SStefan Roese		recalculate the memory size from the SDRAM controller setup
29695e12e75dSStefan Roese		will have to get fixed in Linux additionally.
297014f73ca6SStefan Roese
297114f73ca6SStefan Roese		This option can be used as a workaround for the 440EPx/GRx
297214f73ca6SStefan Roese		CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
297314f73ca6SStefan Roese		be touched.
297414f73ca6SStefan Roese
297514f73ca6SStefan Roese		WARNING: Please make sure that this value is a multiple of
297614f73ca6SStefan Roese		the Linux page size (normally 4k). If this is not the case,
297714f73ca6SStefan Roese		then the end address of the Linux memory will be located at a
297814f73ca6SStefan Roese		non page size aligned address and this could cause major
297914f73ca6SStefan Roese		problems.
298014f73ca6SStefan Roese
29816d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_LOADS_BAUD_CHANGE:
2982c609719bSwdenk		Enable temporary baudrate change while serial download
2983c609719bSwdenk
29846d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SDRAM_BASE:
2985c609719bSwdenk		Physical start address of SDRAM. _Must_ be 0 here.
2986c609719bSwdenk
29876d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_BASE:
2988c609719bSwdenk		Physical start address of Flash memory.
2989c609719bSwdenk
29906d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MONITOR_BASE:
2991c609719bSwdenk		Physical start address of boot monitor code (set by
2992c609719bSwdenk		make config files to be same as the text base address
299314d0a02aSWolfgang Denk		(CONFIG_SYS_TEXT_BASE) used when linking) - same as
29946d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FLASH_BASE when booting from flash.
2995c609719bSwdenk
29966d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MONITOR_LEN:
29973b57fe0aSwdenk		Size of memory reserved for monitor code, used to
29983b57fe0aSwdenk		determine _at_compile_time_ (!) if the environment is
29993b57fe0aSwdenk		embedded within the U-Boot image, or in a separate
30003b57fe0aSwdenk		flash sector.
3001c609719bSwdenk
30026d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MALLOC_LEN:
3003c609719bSwdenk		Size of DRAM reserved for malloc() use.
3004c609719bSwdenk
3005d59476b6SSimon Glass- CONFIG_SYS_MALLOC_F_LEN
3006d59476b6SSimon Glass		Size of the malloc() pool for use before relocation. If
3007d59476b6SSimon Glass		this is defined, then a very simple malloc() implementation
3008d59476b6SSimon Glass		will become available before relocation. The address is just
3009d59476b6SSimon Glass		below the global data, and the stack is moved down to make
3010d59476b6SSimon Glass		space.
3011d59476b6SSimon Glass
3012d59476b6SSimon Glass		This feature allocates regions with increasing addresses
3013d59476b6SSimon Glass		within the region. calloc() is supported, but realloc()
3014d59476b6SSimon Glass		is not available. free() is supported but does nothing.
3015b445bbb4SJeremiah Mahler		The memory will be freed (or in fact just forgotten) when
3016d59476b6SSimon Glass		U-Boot relocates itself.
3017d59476b6SSimon Glass
301838687ae6SSimon Glass- CONFIG_SYS_MALLOC_SIMPLE
301938687ae6SSimon Glass		Provides a simple and small malloc() and calloc() for those
302038687ae6SSimon Glass		boards which do not use the full malloc in SPL (which is
302138687ae6SSimon Glass		enabled with CONFIG_SYS_SPL_MALLOC_START).
302238687ae6SSimon Glass
30231dfdd9baSThierry Reding- CONFIG_SYS_NONCACHED_MEMORY:
30241dfdd9baSThierry Reding		Size of non-cached memory area. This area of memory will be
30251dfdd9baSThierry Reding		typically located right below the malloc() area and mapped
30261dfdd9baSThierry Reding		uncached in the MMU. This is useful for drivers that would
30271dfdd9baSThierry Reding		otherwise require a lot of explicit cache maintenance. For
30281dfdd9baSThierry Reding		some drivers it's also impossible to properly maintain the
30291dfdd9baSThierry Reding		cache. For example if the regions that need to be flushed
30301dfdd9baSThierry Reding		are not a multiple of the cache-line size, *and* padding
30311dfdd9baSThierry Reding		cannot be allocated between the regions to align them (i.e.
30321dfdd9baSThierry Reding		if the HW requires a contiguous array of regions, and the
30331dfdd9baSThierry Reding		size of each region is not cache-aligned), then a flush of
30341dfdd9baSThierry Reding		one region may result in overwriting data that hardware has
30351dfdd9baSThierry Reding		written to another region in the same cache-line. This can
30361dfdd9baSThierry Reding		happen for example in network drivers where descriptors for
30371dfdd9baSThierry Reding		buffers are typically smaller than the CPU cache-line (e.g.
30381dfdd9baSThierry Reding		16 bytes vs. 32 or 64 bytes).
30391dfdd9baSThierry Reding
30401dfdd9baSThierry Reding		Non-cached memory is only supported on 32-bit ARM at present.
30411dfdd9baSThierry Reding
30426d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BOOTM_LEN:
304315940c9aSStefan Roese		Normally compressed uImages are limited to an
304415940c9aSStefan Roese		uncompressed size of 8 MBytes. If this is not enough,
30456d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		you can define CONFIG_SYS_BOOTM_LEN in your board config file
304615940c9aSStefan Roese		to adjust this setting to your needs.
3047c609719bSwdenk
30486d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BOOTMAPSZ:
3049c609719bSwdenk		Maximum size of memory mapped by the startup code of
3050c609719bSwdenk		the Linux kernel; all data that must be processed by
30517d721e34SBartlomiej Sieka		the Linux kernel (bd_info, boot arguments, FDT blob if
30527d721e34SBartlomiej Sieka		used) must be put below this limit, unless "bootm_low"
30531bce2aebSRobert P. J. Day		environment variable is defined and non-zero. In such case
30547d721e34SBartlomiej Sieka		all data for the Linux kernel must be between "bootm_low"
3055c3624e6eSGrant Likely		and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.	 The environment
3056c3624e6eSGrant Likely		variable "bootm_mapsize" will override the value of
3057c3624e6eSGrant Likely		CONFIG_SYS_BOOTMAPSZ.  If CONFIG_SYS_BOOTMAPSZ is undefined,
3058c3624e6eSGrant Likely		then the value in "bootm_size" will be used instead.
3059c609719bSwdenk
3060fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_RAMDISK_HIGH:
3061fca43cc8SJohn Rigby		Enable initrd_high functionality.  If defined then the
3062fca43cc8SJohn Rigby		initrd_high feature is enabled and the bootm ramdisk subcommand
3063fca43cc8SJohn Rigby		is enabled.
3064fca43cc8SJohn Rigby
3065fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_GET_CMDLINE:
3066fca43cc8SJohn Rigby		Enables allocating and saving kernel cmdline in space between
3067fca43cc8SJohn Rigby		"bootm_low" and "bootm_low" + BOOTMAPSZ.
3068fca43cc8SJohn Rigby
3069fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_GET_KBD:
3070fca43cc8SJohn Rigby		Enables allocating and saving a kernel copy of the bd_info in
3071fca43cc8SJohn Rigby		space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3072fca43cc8SJohn Rigby
30736d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAX_FLASH_BANKS:
3074c609719bSwdenk		Max number of Flash memory banks
3075c609719bSwdenk
30766d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAX_FLASH_SECT:
3077c609719bSwdenk		Max number of sectors on a Flash chip
3078c609719bSwdenk
30796d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_ERASE_TOUT:
3080c609719bSwdenk		Timeout for Flash erase operations (in ms)
3081c609719bSwdenk
30826d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_WRITE_TOUT:
3083c609719bSwdenk		Timeout for Flash write operations (in ms)
3084c609719bSwdenk
30856d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_LOCK_TOUT
30868564acf9Swdenk		Timeout for Flash set sector lock bit operation (in ms)
30878564acf9Swdenk
30886d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_UNLOCK_TOUT
30898564acf9Swdenk		Timeout for Flash clear lock bits operation (in ms)
30908564acf9Swdenk
30916d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_PROTECTION
30928564acf9Swdenk		If defined, hardware flash sectors protection is used
30938564acf9Swdenk		instead of U-Boot software protection.
30948564acf9Swdenk
30956d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_DIRECT_FLASH_TFTP:
3096c609719bSwdenk
3097c609719bSwdenk		Enable TFTP transfers directly to flash memory;
3098c609719bSwdenk		without this option such a download has to be
3099c609719bSwdenk		performed in two steps: (1) download to RAM, and (2)
3100c609719bSwdenk		copy from RAM to flash.
3101c609719bSwdenk
3102c609719bSwdenk		The two-step approach is usually more reliable, since
3103c609719bSwdenk		you can check if the download worked before you erase
310411ccc33fSMarcel Ziswiler		the flash, but in some situations (when system RAM is
310511ccc33fSMarcel Ziswiler		too limited to allow for a temporary copy of the
3106c609719bSwdenk		downloaded image) this option may be very useful.
3107c609719bSwdenk
31086d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_CFI:
3109c609719bSwdenk		Define if the flash driver uses extra elements in the
31105653fc33Swdenk		common flash structure for storing flash geometry.
31115653fc33Swdenk
311200b1883aSJean-Christophe PLAGNIOL-VILLARD- CONFIG_FLASH_CFI_DRIVER
31135653fc33Swdenk		This option also enables the building of the cfi_flash driver
31145653fc33Swdenk		in the drivers directory
311553cf9435Sstroese
311691809ed5SPiotr Ziecik- CONFIG_FLASH_CFI_MTD
311791809ed5SPiotr Ziecik		This option enables the building of the cfi_mtd driver
311891809ed5SPiotr Ziecik		in the drivers directory. The driver exports CFI flash
311991809ed5SPiotr Ziecik		to the MTD layer.
312091809ed5SPiotr Ziecik
31216d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
312296ef831fSGuennadi Liakhovetski		Use buffered writes to flash.
312396ef831fSGuennadi Liakhovetski
312496ef831fSGuennadi Liakhovetski- CONFIG_FLASH_SPANSION_S29WS_N
312596ef831fSGuennadi Liakhovetski		s29ws-n MirrorBit flash has non-standard addresses for buffered
312696ef831fSGuennadi Liakhovetski		write commands.
312796ef831fSGuennadi Liakhovetski
31286d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_QUIET_TEST
31295568e613SStefan Roese		If this option is defined, the common CFI flash doesn't
31305568e613SStefan Roese		print it's warning upon not recognized FLASH banks. This
31315568e613SStefan Roese		is useful, if some of the configured banks are only
31325568e613SStefan Roese		optionally available.
31335568e613SStefan Roese
31349a042e9cSJerry Van Baren- CONFIG_FLASH_SHOW_PROGRESS
31359a042e9cSJerry Van Baren		If defined (must be an integer), print out countdown
31369a042e9cSJerry Van Baren		digits and dots.  Recommended value: 45 (9..1) for 80
31379a042e9cSJerry Van Baren		column displays, 15 (3..1) for 40 column displays.
31389a042e9cSJerry Van Baren
3139352ef3f1SStefan Roese- CONFIG_FLASH_VERIFY
3140352ef3f1SStefan Roese		If defined, the content of the flash (destination) is compared
3141352ef3f1SStefan Roese		against the source after the write operation. An error message
3142352ef3f1SStefan Roese		will be printed when the contents are not identical.
3143352ef3f1SStefan Roese		Please note that this option is useless in nearly all cases,
3144352ef3f1SStefan Roese		since such flash programming errors usually are detected earlier
3145352ef3f1SStefan Roese		while unprotecting/erasing/programming. Please only enable
3146352ef3f1SStefan Roese		this option if you really know what you are doing.
3147352ef3f1SStefan Roese
31486d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_RX_ETH_BUFFER:
314911ccc33fSMarcel Ziswiler		Defines the number of Ethernet receive buffers. On some
315011ccc33fSMarcel Ziswiler		Ethernet controllers it is recommended to set this value
315153cf9435Sstroese		to 8 or even higher (EEPRO100 or 405 EMAC), since all
315253cf9435Sstroese		buffers can be full shortly after enabling the interface
315311ccc33fSMarcel Ziswiler		on high Ethernet traffic.
315453cf9435Sstroese		Defaults to 4 if not defined.
3155c609719bSwdenk
3156ea882bafSWolfgang Denk- CONFIG_ENV_MAX_ENTRIES
3157ea882bafSWolfgang Denk
3158ea882bafSWolfgang Denk	Maximum number of entries in the hash table that is used
3159ea882bafSWolfgang Denk	internally to store the environment settings. The default
3160ea882bafSWolfgang Denk	setting is supposed to be generous and should work in most
3161ea882bafSWolfgang Denk	cases. This setting can be used to tune behaviour; see
3162ea882bafSWolfgang Denk	lib/hashtable.c for details.
3163ea882bafSWolfgang Denk
31642598090bSJoe Hershberger- CONFIG_ENV_FLAGS_LIST_DEFAULT
31652598090bSJoe Hershberger- CONFIG_ENV_FLAGS_LIST_STATIC
31661bce2aebSRobert P. J. Day	Enable validation of the values given to environment variables when
31672598090bSJoe Hershberger	calling env set.  Variables can be restricted to only decimal,
31682598090bSJoe Hershberger	hexadecimal, or boolean.  If CONFIG_CMD_NET is also defined,
31692598090bSJoe Hershberger	the variables can also be restricted to IP address or MAC address.
31702598090bSJoe Hershberger
31712598090bSJoe Hershberger	The format of the list is:
31722598090bSJoe Hershberger		type_attribute = [s|d|x|b|i|m]
3173b445bbb4SJeremiah Mahler		access_attribute = [a|r|o|c]
3174b445bbb4SJeremiah Mahler		attributes = type_attribute[access_attribute]
31752598090bSJoe Hershberger		entry = variable_name[:attributes]
31762598090bSJoe Hershberger		list = entry[,list]
31772598090bSJoe Hershberger
31782598090bSJoe Hershberger	The type attributes are:
31792598090bSJoe Hershberger		s - String (default)
31802598090bSJoe Hershberger		d - Decimal
31812598090bSJoe Hershberger		x - Hexadecimal
31822598090bSJoe Hershberger		b - Boolean ([1yYtT|0nNfF])
31832598090bSJoe Hershberger		i - IP address
31842598090bSJoe Hershberger		m - MAC address
31852598090bSJoe Hershberger
3186267541f7SJoe Hershberger	The access attributes are:
3187267541f7SJoe Hershberger		a - Any (default)
3188267541f7SJoe Hershberger		r - Read-only
3189267541f7SJoe Hershberger		o - Write-once
3190267541f7SJoe Hershberger		c - Change-default
3191267541f7SJoe Hershberger
31922598090bSJoe Hershberger	- CONFIG_ENV_FLAGS_LIST_DEFAULT
31932598090bSJoe Hershberger		Define this to a list (string) to define the ".flags"
3194b445bbb4SJeremiah Mahler		environment variable in the default or embedded environment.
31952598090bSJoe Hershberger
31962598090bSJoe Hershberger	- CONFIG_ENV_FLAGS_LIST_STATIC
31972598090bSJoe Hershberger		Define this to a list (string) to define validation that
31982598090bSJoe Hershberger		should be done if an entry is not found in the ".flags"
31992598090bSJoe Hershberger		environment variable.  To override a setting in the static
32002598090bSJoe Hershberger		list, simply add an entry for the same variable name to the
32012598090bSJoe Hershberger		".flags" variable.
32022598090bSJoe Hershberger
3203bdf1fe4eSJoe Hershberger	If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3204bdf1fe4eSJoe Hershberger	regular expression. This allows multiple variables to define the same
3205bdf1fe4eSJoe Hershberger	flags without explicitly listing them for each variable.
3206bdf1fe4eSJoe Hershberger
3207267541f7SJoe Hershberger- CONFIG_ENV_ACCESS_IGNORE_FORCE
3208267541f7SJoe Hershberger	If defined, don't allow the -f switch to env set override variable
3209267541f7SJoe Hershberger	access flags.
3210267541f7SJoe Hershberger
32110d296cc2SGabe Black- CONFIG_USE_STDINT
32120d296cc2SGabe Black	If stdint.h is available with your toolchain you can define this
32130d296cc2SGabe Black	option to enable it. You can provide option 'USE_STDINT=1' when
32140d296cc2SGabe Black	building U-Boot to enable this.
32150d296cc2SGabe Black
3216c609719bSwdenkThe following definitions that deal with the placement and management
3217c609719bSwdenkof environment data (variable area); in general, we support the
3218c609719bSwdenkfollowing configurations:
3219c609719bSwdenk
3220c3eb3fe4SMike Frysinger- CONFIG_BUILD_ENVCRC:
3221c3eb3fe4SMike Frysinger
3222c3eb3fe4SMike Frysinger	Builds up envcrc with the target environment so that external utils
3223c3eb3fe4SMike Frysinger	may easily extract it and embed it in final U-Boot images.
3224c3eb3fe4SMike Frysinger
3225c609719bSwdenkBE CAREFUL! The first access to the environment happens quite early
3226b445bbb4SJeremiah Mahlerin U-Boot initialization (when we try to get the setting of for the
322711ccc33fSMarcel Ziswilerconsole baudrate). You *MUST* have mapped your NVRAM area then, or
3228c609719bSwdenkU-Boot will hang.
3229c609719bSwdenk
3230c609719bSwdenkPlease note that even with NVRAM we still use a copy of the
3231c609719bSwdenkenvironment in RAM: we could work on NVRAM directly, but we want to
3232c609719bSwdenkkeep settings there always unmodified except somebody uses "saveenv"
3233c609719bSwdenkto save the current settings.
3234c609719bSwdenk
32350a85a9e7SLiu GangBE CAREFUL! For some special cases, the local device can not use
32360a85a9e7SLiu Gang"saveenv" command. For example, the local device will get the
3237fc54c7faSLiu Gangenvironment stored in a remote NOR flash by SRIO or PCIE link,
3238fc54c7faSLiu Gangbut it can not erase, write this NOR flash by SRIO or PCIE interface.
32390a85a9e7SLiu Gang
3240b74ab737SGuennadi Liakhovetski- CONFIG_NAND_ENV_DST
3241b74ab737SGuennadi Liakhovetski
3242b74ab737SGuennadi Liakhovetski	Defines address in RAM to which the nand_spl code should copy the
3243b74ab737SGuennadi Liakhovetski	environment. If redundant environment is used, it will be copied to
3244b74ab737SGuennadi Liakhovetski	CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3245b74ab737SGuennadi Liakhovetski
3246e881cb56SBruce AdlerPlease note that the environment is read-only until the monitor
3247c609719bSwdenkhas been relocated to RAM and a RAM copy of the environment has been
324800caae6dSSimon Glasscreated; also, when using EEPROM you will have to use env_get_f()
3249c609719bSwdenkuntil then to read environment variables.
3250c609719bSwdenk
325185ec0bccSwdenkThe environment is protected by a CRC32 checksum. Before the monitor
325285ec0bccSwdenkis relocated into RAM, as a result of a bad CRC you will be working
325385ec0bccSwdenkwith the compiled-in default environment - *silently*!!! [This is
325485ec0bccSwdenknecessary, because the first environment variable we need is the
325585ec0bccSwdenk"baudrate" setting for the console - if we have a bad CRC, we don't
325685ec0bccSwdenkhave any device yet where we could complain.]
3257c609719bSwdenk
3258c609719bSwdenkNote: once the monitor has been relocated, then it will complain if
3259c609719bSwdenkthe default environment is used; a new CRC is computed as soon as you
326085ec0bccSwdenkuse the "saveenv" command to store a valid environment.
3261c609719bSwdenk
32626d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3263fc3e2165Swdenk		Echo the inverted Ethernet link state to the fault LED.
3264fc3e2165Swdenk
32656d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3266fc3e2165Swdenk		      also needs to be defined.
3267fc3e2165Swdenk
32686d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FAULT_MII_ADDR:
3269fc3e2165Swdenk		MII address of the PHY to check for the Ethernet link state.
3270c609719bSwdenk
3271f5675aa5SRon Madrid- CONFIG_NS16550_MIN_FUNCTIONS:
3272f5675aa5SRon Madrid		Define this if you desire to only have use of the NS16550_init
3273f5675aa5SRon Madrid		and NS16550_putc functions for the serial driver located at
3274f5675aa5SRon Madrid		drivers/serial/ns16550.c.  This option is useful for saving
3275f5675aa5SRon Madrid		space for already greatly restricted images, including but not
3276f5675aa5SRon Madrid		limited to NAND_SPL configurations.
3277f5675aa5SRon Madrid
3278b2b92f53SSimon Glass- CONFIG_DISPLAY_BOARDINFO
3279b2b92f53SSimon Glass		Display information about the board that U-Boot is running on
3280b2b92f53SSimon Glass		when U-Boot starts up. The board function checkboard() is called
3281b2b92f53SSimon Glass		to do this.
3282b2b92f53SSimon Glass
3283e2e3e2b1SSimon Glass- CONFIG_DISPLAY_BOARDINFO_LATE
3284e2e3e2b1SSimon Glass		Similar to the previous option, but display this information
3285e2e3e2b1SSimon Glass		later, once stdio is running and output goes to the LCD, if
3286e2e3e2b1SSimon Glass		present.
3287e2e3e2b1SSimon Glass
3288feb85801SSascha Silbe- CONFIG_BOARD_SIZE_LIMIT:
3289feb85801SSascha Silbe		Maximum size of the U-Boot image. When defined, the
3290feb85801SSascha Silbe		build system checks that the actual size does not
3291feb85801SSascha Silbe		exceed it.
3292feb85801SSascha Silbe
3293c609719bSwdenkLow Level (hardware related) configuration options:
3294dc7c9a1aSwdenk---------------------------------------------------
3295c609719bSwdenk
32966d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CACHELINE_SIZE:
3297c609719bSwdenk		Cache Line Size of the CPU.
3298c609719bSwdenk
3299e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_DEFAULT:
3300e46fedfeSTimur Tabi		Default (power-on reset) physical address of CCSR on Freescale
3301e46fedfeSTimur Tabi		PowerPC SOCs.
3302e46fedfeSTimur Tabi
3303e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR:
3304e46fedfeSTimur Tabi		Virtual address of CCSR.  On a 32-bit build, this is typically
3305e46fedfeSTimur Tabi		the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3306e46fedfeSTimur Tabi
3307e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS:
3308e46fedfeSTimur Tabi		Physical address of CCSR.  CCSR can be relocated to a new
3309e46fedfeSTimur Tabi		physical address, if desired.  In this case, this macro should
3310e46fedfeSTimur Tabi		be set to that address.	 Otherwise, it should be set to the
3311e46fedfeSTimur Tabi		same value as CONFIG_SYS_CCSRBAR_DEFAULT.  For example, CCSR
3312e46fedfeSTimur Tabi		is typically relocated on 36-bit builds.  It is recommended
3313e46fedfeSTimur Tabi		that this macro be defined via the _HIGH and _LOW macros:
3314e46fedfeSTimur Tabi
3315e46fedfeSTimur Tabi		#define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3316e46fedfeSTimur Tabi			* 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3317e46fedfeSTimur Tabi
3318e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3319e46fedfeSTimur Tabi		Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS.	This value is typically
3320e46fedfeSTimur Tabi		either 0 (32-bit build) or 0xF (36-bit build).	This macro is
3321e46fedfeSTimur Tabi		used in assembly code, so it must not contain typecasts or
3322e46fedfeSTimur Tabi		integer size suffixes (e.g. "ULL").
3323e46fedfeSTimur Tabi
3324e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3325e46fedfeSTimur Tabi		Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS.  This macro is
3326e46fedfeSTimur Tabi		used in assembly code, so it must not contain typecasts or
3327e46fedfeSTimur Tabi		integer size suffixes (e.g. "ULL").
3328e46fedfeSTimur Tabi
3329e46fedfeSTimur Tabi- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3330e46fedfeSTimur Tabi		If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3331e46fedfeSTimur Tabi		forced to a value that ensures that CCSR is not relocated.
3332e46fedfeSTimur Tabi
33337f6c2cbcSwdenk- Floppy Disk Support:
33346d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FDC_DRIVE_NUMBER
33357f6c2cbcSwdenk
33367f6c2cbcSwdenk		the default drive number (default value 0)
33377f6c2cbcSwdenk
33386d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_ISA_IO_STRIDE
33397f6c2cbcSwdenk
334011ccc33fSMarcel Ziswiler		defines the spacing between FDC chipset registers
33417f6c2cbcSwdenk		(default value 1)
33427f6c2cbcSwdenk
33436d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_ISA_IO_OFFSET
33447f6c2cbcSwdenk
33457f6c2cbcSwdenk		defines the offset of register from address. It
33467f6c2cbcSwdenk		depends on which part of the data bus is connected to
334711ccc33fSMarcel Ziswiler		the FDC chipset. (default value 0)
33487f6c2cbcSwdenk
33496d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
33506d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
33517f6c2cbcSwdenk		default value.
33527f6c2cbcSwdenk
33536d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		if CONFIG_SYS_FDC_HW_INIT is defined, then the function
33547f6c2cbcSwdenk		fdc_hw_init() is called at the beginning of the FDC
33557f6c2cbcSwdenk		setup. fdc_hw_init() must be provided by the board
3356b445bbb4SJeremiah Mahler		source code. It is used to make hardware-dependent
33577f6c2cbcSwdenk		initializations.
33587f6c2cbcSwdenk
33590abddf82SMacpaul Lin- CONFIG_IDE_AHB:
33600abddf82SMacpaul Lin		Most IDE controllers were designed to be connected with PCI
33610abddf82SMacpaul Lin		interface. Only few of them were designed for AHB interface.
33620abddf82SMacpaul Lin		When software is doing ATA command and data transfer to
33630abddf82SMacpaul Lin		IDE devices through IDE-AHB controller, some additional
33640abddf82SMacpaul Lin		registers accessing to these kind of IDE-AHB controller
3365b445bbb4SJeremiah Mahler		is required.
33660abddf82SMacpaul Lin
33676d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_IMMR:	Physical address of the Internal Memory.
336825d6712aSwdenk		DO NOT CHANGE unless you know exactly what you're
3369907208c4SChristophe Leroy		doing! (11-4) [MPC8xx systems only]
3370c609719bSwdenk
33716d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_INIT_RAM_ADDR:
3372c609719bSwdenk
33737152b1d0Swdenk		Start address of memory area that can be used for
3374c609719bSwdenk		initial data and stack; please note that this must be
3375c609719bSwdenk		writable memory that is working WITHOUT special
3376c609719bSwdenk		initialization, i. e. you CANNOT use normal RAM which
3377c609719bSwdenk		will become available only after programming the
3378c609719bSwdenk		memory controller and running certain initialization
3379c609719bSwdenk		sequences.
3380c609719bSwdenk
3381c609719bSwdenk		U-Boot uses the following memory types:
3382907208c4SChristophe Leroy		- MPC8xx: IMMR (internal memory of the CPU)
3383c609719bSwdenk
33846d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_GBL_DATA_OFFSET:
3385c609719bSwdenk
3386c609719bSwdenk		Offset of the initial data structure in the memory
33876d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
33886d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3389c609719bSwdenk		data is located at the end of the available space
3390553f0982SWolfgang Denk		(sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3391acd51f9dSSimon Glass		GENERATED_GBL_DATA_SIZE), and the initial stack is just
33926d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
33936d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_GBL_DATA_OFFSET) downward.
3394c609719bSwdenk
3395c609719bSwdenk	Note:
3396c609719bSwdenk		On the MPC824X (or other systems that use the data
3397c609719bSwdenk		cache for initial memory) the address chosen for
33986d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3399c609719bSwdenk		point to an otherwise UNUSED address space between
3400c609719bSwdenk		the top of RAM and the start of the PCI space.
3401c609719bSwdenk
34026d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SCCR:	System Clock and reset Control Register (15-27)
3403c609719bSwdenk
34046d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_OR_TIMING_SDRAM:
3405c609719bSwdenk		SDRAM timing
3406c609719bSwdenk
34076d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAMR_PTA:
3408c609719bSwdenk		periodic timer for refresh
3409c609719bSwdenk
34106d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
34116d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
34126d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
34136d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_BR1_PRELIM:
3414c609719bSwdenk		Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3415c609719bSwdenk
3416c609719bSwdenk- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
34176d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
34186d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3419c609719bSwdenk		Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3420c609719bSwdenk
342169fd2d3bSAndrew Sharp- CONFIG_PCI_ENUM_ONLY
3422b445bbb4SJeremiah Mahler		Only scan through and get the devices on the buses.
342369fd2d3bSAndrew Sharp		Don't do any setup work, presumably because someone or
342469fd2d3bSAndrew Sharp		something has already done it, and we don't need to do it
342569fd2d3bSAndrew Sharp		a second time.	Useful for platforms that are pre-booted
342669fd2d3bSAndrew Sharp		by coreboot or similar.
342769fd2d3bSAndrew Sharp
3428842033e6SGabor Juhos- CONFIG_PCI_INDIRECT_BRIDGE:
3429842033e6SGabor Juhos		Enable support for indirect PCI bridges.
3430842033e6SGabor Juhos
3431a09b9b68SKumar Gala- CONFIG_SYS_SRIO:
3432a09b9b68SKumar Gala		Chip has SRIO or not
3433a09b9b68SKumar Gala
3434a09b9b68SKumar Gala- CONFIG_SRIO1:
3435a09b9b68SKumar Gala		Board has SRIO 1 port available
3436a09b9b68SKumar Gala
3437a09b9b68SKumar Gala- CONFIG_SRIO2:
3438a09b9b68SKumar Gala		Board has SRIO 2 port available
3439a09b9b68SKumar Gala
3440c8b28152SLiu Gang- CONFIG_SRIO_PCIE_BOOT_MASTER
3441c8b28152SLiu Gang		Board can support master function for Boot from SRIO and PCIE
3442c8b28152SLiu Gang
3443a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_VIRT:
3444a09b9b68SKumar Gala		Virtual Address of SRIO port 'n' memory region
3445a09b9b68SKumar Gala
3446a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_PHYS:
3447a09b9b68SKumar Gala		Physical Address of SRIO port 'n' memory region
3448a09b9b68SKumar Gala
3449a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_SIZE:
3450a09b9b68SKumar Gala		Size of SRIO port 'n' memory region
3451a09b9b68SKumar Gala
345266bd1846SFabio Estevam- CONFIG_SYS_NAND_BUSWIDTH_16BIT
345366bd1846SFabio Estevam		Defined to tell the NAND controller that the NAND chip is using
345466bd1846SFabio Estevam		a 16 bit bus.
345566bd1846SFabio Estevam		Not all NAND drivers use this symbol.
3456a430e916SFabio Estevam		Example of drivers that use it:
345766bd1846SFabio Estevam		- drivers/mtd/nand/ndfc.c
3458a430e916SFabio Estevam		- drivers/mtd/nand/mxc_nand.c
3459eced4626SAlex Waterman
3460eced4626SAlex Waterman- CONFIG_SYS_NDFC_EBC0_CFG
3461eced4626SAlex Waterman		Sets the EBC0_CFG register for the NDFC. If not defined
3462eced4626SAlex Waterman		a default value will be used.
3463eced4626SAlex Waterman
3464bb99ad6dSBen Warren- CONFIG_SPD_EEPROM
3465218ca724SWolfgang Denk		Get DDR timing information from an I2C EEPROM. Common
3466218ca724SWolfgang Denk		with pluggable memory modules such as SODIMMs
3467218ca724SWolfgang Denk
3468bb99ad6dSBen Warren  SPD_EEPROM_ADDRESS
3469bb99ad6dSBen Warren		I2C address of the SPD EEPROM
3470bb99ad6dSBen Warren
34716d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SPD_BUS_NUM
3472218ca724SWolfgang Denk		If SPD EEPROM is on an I2C bus other than the first
3473218ca724SWolfgang Denk		one, specify here. Note that the value must resolve
3474218ca724SWolfgang Denk		to something your driver can deal with.
3475bb99ad6dSBen Warren
34761b3e3c4fSYork Sun- CONFIG_SYS_DDR_RAW_TIMING
34771b3e3c4fSYork Sun		Get DDR timing information from other than SPD. Common with
34781b3e3c4fSYork Sun		soldered DDR chips onboard without SPD. DDR raw timing
34791b3e3c4fSYork Sun		parameters are extracted from datasheet and hard-coded into
34801b3e3c4fSYork Sun		header files or board specific files.
34811b3e3c4fSYork Sun
34826f5e1dc5SYork Sun- CONFIG_FSL_DDR_INTERACTIVE
34836f5e1dc5SYork Sun		Enable interactive DDR debugging. See doc/README.fsl-ddr.
34846f5e1dc5SYork Sun
3485e32d59a2SYork Sun- CONFIG_FSL_DDR_SYNC_REFRESH
3486e32d59a2SYork Sun		Enable sync of refresh for multiple controllers.
3487e32d59a2SYork Sun
34884516ff81SYork Sun- CONFIG_FSL_DDR_BIST
34894516ff81SYork Sun		Enable built-in memory test for Freescale DDR controllers.
34904516ff81SYork Sun
34916d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_83XX_DDR_USES_CS0
3492218ca724SWolfgang Denk		Only for 83xx systems. If specified, then DDR should
3493218ca724SWolfgang Denk		be configured using CS0 and CS1 instead of CS2 and CS3.
34942ad6b513STimur Tabi
3495c26e454dSwdenk- CONFIG_RMII
3496c26e454dSwdenk		Enable RMII mode for all FECs.
3497c26e454dSwdenk		Note that this is a global option, we can't
3498c26e454dSwdenk		have one FEC in standard MII mode and another in RMII mode.
3499c26e454dSwdenk
35005cf91d6bSwdenk- CONFIG_CRC32_VERIFY
35015cf91d6bSwdenk		Add a verify option to the crc32 command.
35025cf91d6bSwdenk		The syntax is:
35035cf91d6bSwdenk
35045cf91d6bSwdenk		=> crc32 -v <address> <count> <crc32>
35055cf91d6bSwdenk
35065cf91d6bSwdenk		Where address/count indicate a memory area
35075cf91d6bSwdenk		and crc32 is the correct crc32 which the
35085cf91d6bSwdenk		area should have.
35095cf91d6bSwdenk
351056523f12Swdenk- CONFIG_LOOPW
351156523f12Swdenk		Add the "loopw" memory command. This only takes effect if
3512493f420eSSimon Glass		the memory commands are activated globally (CONFIG_CMD_MEMORY).
351356523f12Swdenk
35147b466641Sstroese- CONFIG_MX_CYCLIC
35157b466641Sstroese		Add the "mdc" and "mwc" memory commands. These are cyclic
35167b466641Sstroese		"md/mw" commands.
35177b466641Sstroese		Examples:
35187b466641Sstroese
35197b466641Sstroese		=> mdc.b 10 4 500
35207b466641Sstroese		This command will print 4 bytes (10,11,12,13) each 500 ms.
35217b466641Sstroese
35227b466641Sstroese		=> mwc.l 100 12345678 10
35237b466641Sstroese		This command will write 12345678 to address 100 all 10 ms.
35247b466641Sstroese
35257b466641Sstroese		This only takes effect if the memory commands are activated
3526493f420eSSimon Glass		globally (CONFIG_CMD_MEMORY).
35277b466641Sstroese
35288aa1a2d1Swdenk- CONFIG_SKIP_LOWLEVEL_INIT
3529afc1ce82SMacpaul Lin		[ARM, NDS32, MIPS only] If this variable is defined, then certain
3530e03f3169SWolfgang Denk		low level initializations (like setting up the memory
3531e03f3169SWolfgang Denk		controller) are omitted and/or U-Boot does not
3532e03f3169SWolfgang Denk		relocate itself into RAM.
35338aa1a2d1Swdenk
3534e03f3169SWolfgang Denk		Normally this variable MUST NOT be defined. The only
3535e03f3169SWolfgang Denk		exception is when U-Boot is loaded (to RAM) by some
3536e03f3169SWolfgang Denk		other boot loader or by a debugger which performs
3537e03f3169SWolfgang Denk		these initializations itself.
35388aa1a2d1Swdenk
3539b5bd0982SSimon Glass- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3540b5bd0982SSimon Glass		[ARM926EJ-S only] This allows just the call to lowlevel_init()
354190211f77Syeongjun Kim		to be skipped. The normal CP15 init (such as enabling the
3542b5bd0982SSimon Glass		instruction cache) is still performed.
3543b5bd0982SSimon Glass
3544401bb30bSAneesh V- CONFIG_SPL_BUILD
3545df81238bSMagnus Lilja		Modifies the behaviour of start.S when compiling a loader
3546df81238bSMagnus Lilja		that is executed before the actual U-Boot. E.g. when
3547df81238bSMagnus Lilja		compiling a NAND SPL.
3548400558b5Swdenk
35493aa29de0SYing Zhang- CONFIG_TPL_BUILD
35503aa29de0SYing Zhang		Modifies the behaviour of start.S  when compiling a loader
35513aa29de0SYing Zhang		that is executed after the SPL and before the actual U-Boot.
35523aa29de0SYing Zhang		It is loaded by the SPL.
35533aa29de0SYing Zhang
35545df572f0SYing Zhang- CONFIG_SYS_MPC85XX_NO_RESETVEC
35555df572f0SYing Zhang		Only for 85xx systems. If this variable is specified, the section
35565df572f0SYing Zhang		.resetvec is not kept and the section .bootpg is placed in the
35575df572f0SYing Zhang		previous 4k of the .text section.
35585df572f0SYing Zhang
35594213fc29SSimon Glass- CONFIG_ARCH_MAP_SYSMEM
35604213fc29SSimon Glass		Generally U-Boot (and in particular the md command) uses
35614213fc29SSimon Glass		effective address. It is therefore not necessary to regard
35624213fc29SSimon Glass		U-Boot address as virtual addresses that need to be translated
35634213fc29SSimon Glass		to physical addresses. However, sandbox requires this, since
35644213fc29SSimon Glass		it maintains its own little RAM buffer which contains all
35654213fc29SSimon Glass		addressable memory. This option causes some memory accesses
35664213fc29SSimon Glass		to be mapped through map_sysmem() / unmap_sysmem().
35674213fc29SSimon Glass
3568588a13f7SSimon Glass- CONFIG_X86_RESET_VECTOR
3569588a13f7SSimon Glass		If defined, the x86 reset vector code is included. This is not
3570588a13f7SSimon Glass		needed when U-Boot is running from Coreboot.
3571b16f521aSGabe Black
357216678eb4SHeiko Schocher- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
357316678eb4SHeiko Schocher		Enables the RTC32K OSC on AM33xx based plattforms
357416678eb4SHeiko Schocher
3575999d7d32SKaricheri, Muralidharan- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3576999d7d32SKaricheri, Muralidharan		Option to disable subpage write in NAND driver
3577999d7d32SKaricheri, Muralidharan		driver that uses this:
3578999d7d32SKaricheri, Muralidharan		drivers/mtd/nand/davinci_nand.c
3579999d7d32SKaricheri, Muralidharan
3580f2717b47STimur TabiFreescale QE/FMAN Firmware Support:
3581f2717b47STimur Tabi-----------------------------------
3582f2717b47STimur Tabi
3583f2717b47STimur TabiThe Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3584f2717b47STimur Tabiloading of "firmware", which is encoded in the QE firmware binary format.
3585f2717b47STimur TabiThis firmware often needs to be loaded during U-Boot booting, so macros
3586f2717b47STimur Tabiare used to identify the storage device (NOR flash, SPI, etc) and the address
3587f2717b47STimur Tabiwithin that device.
3588f2717b47STimur Tabi
3589dcf1d774SZhao Qiang- CONFIG_SYS_FMAN_FW_ADDR
3590dcf1d774SZhao Qiang	The address in the storage device where the FMAN microcode is located.  The
3591dcf1d774SZhao Qiang	meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3592dcf1d774SZhao Qiang	is also specified.
3593dcf1d774SZhao Qiang
3594dcf1d774SZhao Qiang- CONFIG_SYS_QE_FW_ADDR
3595dcf1d774SZhao Qiang	The address in the storage device where the QE microcode is located.  The
3596f2717b47STimur Tabi	meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3597f2717b47STimur Tabi	is also specified.
3598f2717b47STimur Tabi
3599f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_LENGTH
3600f2717b47STimur Tabi	The maximum possible size of the firmware.  The firmware binary format
3601f2717b47STimur Tabi	has a field that specifies the actual size of the firmware, but it
3602f2717b47STimur Tabi	might not be possible to read any part of the firmware unless some
3603f2717b47STimur Tabi	local storage is allocated to hold the entire firmware first.
3604f2717b47STimur Tabi
3605f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3606f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3607f2717b47STimur Tabi	normal addressable memory via the LBC.  CONFIG_SYS_FMAN_FW_ADDR is the
3608f2717b47STimur Tabi	virtual address in NOR flash.
3609f2717b47STimur Tabi
3610f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3611f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located in NAND flash.
3612f2717b47STimur Tabi	CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3613f2717b47STimur Tabi
3614f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3615f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located on the primary SD/MMC
3616f2717b47STimur Tabi	device.  CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3617f2717b47STimur Tabi
3618292dc6c5SLiu Gang- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3619292dc6c5SLiu Gang	Specifies that QE/FMAN firmware is located in the remote (master)
3620292dc6c5SLiu Gang	memory space.	CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
3621fc54c7faSLiu Gang	can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3622fc54c7faSLiu Gang	window->master inbound window->master LAW->the ucode address in
3623fc54c7faSLiu Gang	master's memory space.
3624f2717b47STimur Tabi
3625b940ca64SJ. German RiveraFreescale Layerscape Management Complex Firmware Support:
3626b940ca64SJ. German Rivera---------------------------------------------------------
3627b940ca64SJ. German RiveraThe Freescale Layerscape Management Complex (MC) supports the loading of
3628b940ca64SJ. German Rivera"firmware".
3629b940ca64SJ. German RiveraThis firmware often needs to be loaded during U-Boot booting, so macros
3630b940ca64SJ. German Riveraare used to identify the storage device (NOR flash, SPI, etc) and the address
3631b940ca64SJ. German Riverawithin that device.
3632b940ca64SJ. German Rivera
3633b940ca64SJ. German Rivera- CONFIG_FSL_MC_ENET
3634b940ca64SJ. German Rivera	Enable the MC driver for Layerscape SoCs.
3635b940ca64SJ. German Rivera
36365c055089SPrabhakar KushwahaFreescale Layerscape Debug Server Support:
36375c055089SPrabhakar Kushwaha-------------------------------------------
36385c055089SPrabhakar KushwahaThe Freescale Layerscape Debug Server Support supports the loading of
36395c055089SPrabhakar Kushwaha"Debug Server firmware" and triggering SP boot-rom.
36405c055089SPrabhakar KushwahaThis firmware often needs to be loaded during U-Boot booting.
36415c055089SPrabhakar Kushwaha
3642c0492141SYork Sun- CONFIG_SYS_MC_RSV_MEM_ALIGN
3643c0492141SYork Sun	Define alignment of reserved memory MC requires
36445c055089SPrabhakar Kushwaha
3645f3f431a7SPaul KocialkowskiReproducible builds
3646f3f431a7SPaul Kocialkowski-------------------
3647f3f431a7SPaul Kocialkowski
3648f3f431a7SPaul KocialkowskiIn order to achieve reproducible builds, timestamps used in the U-Boot build
3649f3f431a7SPaul Kocialkowskiprocess have to be set to a fixed value.
3650f3f431a7SPaul Kocialkowski
3651f3f431a7SPaul KocialkowskiThis is done using the SOURCE_DATE_EPOCH environment variable.
3652f3f431a7SPaul KocialkowskiSOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3653f3f431a7SPaul Kocialkowskioption for U-Boot or an environment variable in U-Boot.
3654f3f431a7SPaul Kocialkowski
3655f3f431a7SPaul KocialkowskiSOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3656f3f431a7SPaul Kocialkowski
3657c609719bSwdenkBuilding the Software:
3658c609719bSwdenk======================
3659c609719bSwdenk
3660218ca724SWolfgang DenkBuilding U-Boot has been tested in several native build environments
3661218ca724SWolfgang Denkand in many different cross environments. Of course we cannot support
3662218ca724SWolfgang Denkall possibly existing versions of cross development tools in all
3663218ca724SWolfgang Denk(potentially obsolete) versions. In case of tool chain problems we
3664218ca724SWolfgang Denkrecommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3665218ca724SWolfgang Denkwhich is extensively used to build and test U-Boot.
3666c609719bSwdenk
3667218ca724SWolfgang DenkIf you are not using a native environment, it is assumed that you
3668218ca724SWolfgang Denkhave GNU cross compiling tools available in your path. In this case,
3669218ca724SWolfgang Denkyou must set the environment variable CROSS_COMPILE in your shell.
3670218ca724SWolfgang DenkNote that no changes to the Makefile or any other source files are
3671218ca724SWolfgang Denknecessary. For example using the ELDK on a 4xx CPU, please enter:
3672c609719bSwdenk
3673218ca724SWolfgang Denk	$ CROSS_COMPILE=ppc_4xx-
3674218ca724SWolfgang Denk	$ export CROSS_COMPILE
3675c609719bSwdenk
36762f8d396bSPeter TyserNote: If you wish to generate Windows versions of the utilities in
36772f8d396bSPeter Tyser      the tools directory you can use the MinGW toolchain
36782f8d396bSPeter Tyser      (http://www.mingw.org).  Set your HOST tools to the MinGW
36792f8d396bSPeter Tyser      toolchain and execute 'make tools'.  For example:
36802f8d396bSPeter Tyser
36812f8d396bSPeter Tyser       $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
36822f8d396bSPeter Tyser
36832f8d396bSPeter Tyser      Binaries such as tools/mkimage.exe will be created which can
36842f8d396bSPeter Tyser      be executed on computers running Windows.
36852f8d396bSPeter Tyser
3686c609719bSwdenkU-Boot is intended to be simple to build. After installing the
3687c609719bSwdenksources you must configure U-Boot for one specific board type. This
3688c609719bSwdenkis done by typing:
3689c609719bSwdenk
3690ab584d67SHolger Freyther	make NAME_defconfig
3691c609719bSwdenk
3692ab584d67SHolger Freytherwhere "NAME_defconfig" is the name of one of the existing configu-
36934d675ae6SMichael Jonesrations; see boards.cfg for supported names.
369454387ac9Swdenk
3695c609719bSwdenkNote: for some board special configuration names may exist; check if
3696c609719bSwdenk      additional information is available from the board vendor; for
36972729af9dSwdenk      instance, the TQM823L systems are available without (standard)
36982729af9dSwdenk      or with LCD support. You can select such additional "features"
369911ccc33fSMarcel Ziswiler      when choosing the configuration, i. e.
3700c609719bSwdenk
3701ab584d67SHolger Freyther      make TQM823L_defconfig
37022729af9dSwdenk	- will configure for a plain TQM823L, i. e. no LCD support
3703c609719bSwdenk
3704ab584d67SHolger Freyther      make TQM823L_LCD_defconfig
3705c609719bSwdenk	- will configure for a TQM823L with U-Boot console on LCD
3706c609719bSwdenk
3707c609719bSwdenk      etc.
3708c609719bSwdenk
3709c609719bSwdenk
3710c609719bSwdenkFinally, type "make all", and you should get some working U-Boot
37117152b1d0Swdenkimages ready for download to / installation on your system:
3712c609719bSwdenk
3713c609719bSwdenk- "u-boot.bin" is a raw binary image
3714c609719bSwdenk- "u-boot" is an image in ELF binary format
3715c609719bSwdenk- "u-boot.srec" is in Motorola S-Record format
3716c609719bSwdenk
3717baf31249SMarian BalakowiczBy default the build is performed locally and the objects are saved
3718baf31249SMarian Balakowiczin the source directory. One of the two methods can be used to change
3719baf31249SMarian Balakowiczthis behavior and build U-Boot to some external directory:
3720baf31249SMarian Balakowicz
3721baf31249SMarian Balakowicz1. Add O= to the make command line invocations:
3722baf31249SMarian Balakowicz
3723baf31249SMarian Balakowicz	make O=/tmp/build distclean
3724ab584d67SHolger Freyther	make O=/tmp/build NAME_defconfig
3725baf31249SMarian Balakowicz	make O=/tmp/build all
3726baf31249SMarian Balakowicz
3727adbba996STimo Ketola2. Set environment variable KBUILD_OUTPUT to point to the desired location:
3728baf31249SMarian Balakowicz
3729adbba996STimo Ketola	export KBUILD_OUTPUT=/tmp/build
3730baf31249SMarian Balakowicz	make distclean
3731ab584d67SHolger Freyther	make NAME_defconfig
3732baf31249SMarian Balakowicz	make all
3733baf31249SMarian Balakowicz
3734adbba996STimo KetolaNote that the command line "O=" setting overrides the KBUILD_OUTPUT environment
3735baf31249SMarian Balakowiczvariable.
3736baf31249SMarian Balakowicz
3737c609719bSwdenk
3738c609719bSwdenkPlease be aware that the Makefiles assume you are using GNU make, so
3739c609719bSwdenkfor instance on NetBSD you might need to use "gmake" instead of
3740c609719bSwdenknative "make".
3741c609719bSwdenk
3742c609719bSwdenk
3743c609719bSwdenkIf the system board that you have is not listed, then you will need
3744c609719bSwdenkto port U-Boot to your hardware platform. To do this, follow these
3745c609719bSwdenksteps:
3746c609719bSwdenk
37473c1496cdSPhil Sutter1.  Create a new directory to hold your board specific code. Add any
374885ec0bccSwdenk    files you need. In your board directory, you will need at least
37493c1496cdSPhil Sutter    the "Makefile" and a "<board>.c".
37503c1496cdSPhil Sutter2.  Create a new configuration file "include/configs/<board>.h" for
37513c1496cdSPhil Sutter    your board.
3752c609719bSwdenk3.  If you're porting U-Boot to a new CPU, then also create a new
3753c609719bSwdenk    directory to hold your CPU specific code. Add any files you need.
3754ab584d67SHolger Freyther4.  Run "make <board>_defconfig" with your new name.
3755c609719bSwdenk5.  Type "make", and you should get a working "u-boot.srec" file
3756c609719bSwdenk    to be installed on your target system.
375785ec0bccSwdenk6.  Debug and solve any problems that might arise.
3758c609719bSwdenk    [Of course, this last step is much harder than it sounds.]
3759c609719bSwdenk
3760c609719bSwdenk
3761c609719bSwdenkTesting of U-Boot Modifications, Ports to New Hardware, etc.:
3762c609719bSwdenk==============================================================
3763c609719bSwdenk
3764c609719bSwdenkIf you have modified U-Boot sources (for instance added a new board
3765c609719bSwdenkor support for new devices, a new CPU, etc.) you are expected to
3766c609719bSwdenkprovide feedback to the other developers. The feedback normally takes
3767c609719bSwdenkthe form of a "patch", i. e. a context diff against a certain (latest
3768218ca724SWolfgang Denkofficial or latest in the git repository) version of U-Boot sources.
3769c609719bSwdenk
3770c609719bSwdenkBut before you submit such a patch, please verify that your modifi-
3771c609719bSwdenkcation did not break existing code. At least make sure that *ALL* of
3772c609719bSwdenkthe supported boards compile WITHOUT ANY compiler warnings. To do so,
37736de80f21SSimon Glassjust run the buildman script (tools/buildman/buildman), which will
37746de80f21SSimon Glassconfigure and build U-Boot for ALL supported system. Be warned, this
37756de80f21SSimon Glasswill take a while. Please see the buildman README, or run 'buildman -H'
37766de80f21SSimon Glassfor documentation.
3777baf31249SMarian Balakowicz
3778baf31249SMarian Balakowicz
3779c609719bSwdenkSee also "U-Boot Porting Guide" below.
3780c609719bSwdenk
3781c609719bSwdenk
3782c609719bSwdenkMonitor Commands - Overview:
3783c609719bSwdenk============================
3784c609719bSwdenk
3785c609719bSwdenkgo	- start application at address 'addr'
3786c609719bSwdenkrun	- run commands in an environment variable
3787c609719bSwdenkbootm	- boot application image from memory
3788c609719bSwdenkbootp	- boot image via network using BootP/TFTP protocol
378944f074c7SMarek Vasutbootz   - boot zImage from memory
3790c609719bSwdenktftpboot- boot image via network using TFTP protocol
3791c609719bSwdenk	       and env variables "ipaddr" and "serverip"
3792c609719bSwdenk	       (and eventually "gatewayip")
37931fb7cd49SSimon Glasstftpput - upload a file via network using TFTP protocol
3794c609719bSwdenkrarpboot- boot image via network using RARP/TFTP protocol
3795c609719bSwdenkdiskboot- boot from IDE devicebootd   - boot default, i.e., run 'bootcmd'
3796c609719bSwdenkloads	- load S-Record file over serial line
3797c609719bSwdenkloadb	- load binary file over serial line (kermit mode)
3798c609719bSwdenkmd	- memory display
3799c609719bSwdenkmm	- memory modify (auto-incrementing)
3800c609719bSwdenknm	- memory modify (constant address)
3801c609719bSwdenkmw	- memory write (fill)
3802c609719bSwdenkcp	- memory copy
3803c609719bSwdenkcmp	- memory compare
3804c609719bSwdenkcrc32	- checksum calculation
38050f89c54bSPeter Tyseri2c	- I2C sub-system
3806c609719bSwdenksspi	- SPI utility commands
3807c609719bSwdenkbase	- print or set address offset
3808c609719bSwdenkprintenv- print environment variables
3809c609719bSwdenksetenv	- set environment variables
3810c609719bSwdenksaveenv - save environment variables to persistent storage
3811c609719bSwdenkprotect - enable or disable FLASH write protection
3812c609719bSwdenkerase	- erase FLASH memory
3813c609719bSwdenkflinfo	- print FLASH memory information
381410635afaSKarl O. Pincnand	- NAND memory operations (see doc/README.nand)
3815c609719bSwdenkbdinfo	- print Board Info structure
3816c609719bSwdenkiminfo	- print header information for application image
3817c609719bSwdenkconinfo - print console devices and informations
3818c609719bSwdenkide	- IDE sub-system
3819c609719bSwdenkloop	- infinite loop on address range
382056523f12Swdenkloopw	- infinite write loop on address range
3821c609719bSwdenkmtest	- simple RAM test
3822c609719bSwdenkicache	- enable or disable instruction cache
3823c609719bSwdenkdcache	- enable or disable data cache
3824c609719bSwdenkreset	- Perform RESET of the CPU
3825c609719bSwdenkecho	- echo args to console
3826c609719bSwdenkversion - print monitor version
3827c609719bSwdenkhelp	- print online help
3828c609719bSwdenk?	- alias for 'help'
3829c609719bSwdenk
3830c609719bSwdenk
3831c609719bSwdenkMonitor Commands - Detailed Description:
3832c609719bSwdenk========================================
3833c609719bSwdenk
3834c609719bSwdenkTODO.
3835c609719bSwdenk
3836c609719bSwdenkFor now: just type "help <command>".
3837c609719bSwdenk
3838c609719bSwdenk
3839c609719bSwdenkEnvironment Variables:
3840c609719bSwdenk======================
3841c609719bSwdenk
3842c609719bSwdenkU-Boot supports user configuration using Environment Variables which
3843c609719bSwdenkcan be made persistent by saving to Flash memory.
3844c609719bSwdenk
3845c609719bSwdenkEnvironment Variables are set using "setenv", printed using
3846c609719bSwdenk"printenv", and saved to Flash using "saveenv". Using "setenv"
3847c609719bSwdenkwithout a value can be used to delete a variable from the
3848c609719bSwdenkenvironment. As long as you don't save the environment you are
3849c609719bSwdenkworking with an in-memory copy. In case the Flash area containing the
3850c609719bSwdenkenvironment is erased by accident, a default environment is provided.
3851c609719bSwdenk
3852c96f86eeSWolfgang DenkSome configuration options can be set using Environment Variables.
3853c96f86eeSWolfgang Denk
3854c96f86eeSWolfgang DenkList of environment variables (most likely not complete):
3855c609719bSwdenk
3856c609719bSwdenk  baudrate	- see CONFIG_BAUDRATE
3857c609719bSwdenk
3858c609719bSwdenk  bootdelay	- see CONFIG_BOOTDELAY
3859c609719bSwdenk
3860c609719bSwdenk  bootcmd	- see CONFIG_BOOTCOMMAND
3861c609719bSwdenk
3862c609719bSwdenk  bootargs	- Boot arguments when booting an RTOS image
3863c609719bSwdenk
3864c609719bSwdenk  bootfile	- Name of the image to load with TFTP
3865c609719bSwdenk
38667d721e34SBartlomiej Sieka  bootm_low	- Memory range available for image processing in the bootm
38677d721e34SBartlomiej Sieka		  command can be restricted. This variable is given as
38687d721e34SBartlomiej Sieka		  a hexadecimal number and defines lowest address allowed
38697d721e34SBartlomiej Sieka		  for use by the bootm command. See also "bootm_size"
38707d721e34SBartlomiej Sieka		  environment variable. Address defined by "bootm_low" is
38717d721e34SBartlomiej Sieka		  also the base of the initial memory mapping for the Linux
3872c3624e6eSGrant Likely		  kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3873c3624e6eSGrant Likely		  bootm_mapsize.
3874c3624e6eSGrant Likely
3875c3624e6eSGrant Likely  bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3876c3624e6eSGrant Likely		  This variable is given as a hexadecimal number and it
3877c3624e6eSGrant Likely		  defines the size of the memory region starting at base
3878c3624e6eSGrant Likely		  address bootm_low that is accessible by the Linux kernel
3879c3624e6eSGrant Likely		  during early boot.  If unset, CONFIG_SYS_BOOTMAPSZ is used
3880c3624e6eSGrant Likely		  as the default value if it is defined, and bootm_size is
3881c3624e6eSGrant Likely		  used otherwise.
38827d721e34SBartlomiej Sieka
38837d721e34SBartlomiej Sieka  bootm_size	- Memory range available for image processing in the bootm
38847d721e34SBartlomiej Sieka		  command can be restricted. This variable is given as
38857d721e34SBartlomiej Sieka		  a hexadecimal number and defines the size of the region
38867d721e34SBartlomiej Sieka		  allowed for use by the bootm command. See also "bootm_low"
38877d721e34SBartlomiej Sieka		  environment variable.
38887d721e34SBartlomiej Sieka
38894bae9090SBartlomiej Sieka  updatefile	- Location of the software update file on a TFTP server, used
38904bae9090SBartlomiej Sieka		  by the automatic software update feature. Please refer to
38914bae9090SBartlomiej Sieka		  documentation in doc/README.update for more details.
38924bae9090SBartlomiej Sieka
3893c609719bSwdenk  autoload	- if set to "no" (any string beginning with 'n'),
3894c609719bSwdenk		  "bootp" will just load perform a lookup of the
3895c609719bSwdenk		  configuration from the BOOTP server, but not try to
3896c609719bSwdenk		  load any image using TFTP
3897c609719bSwdenk
3898c609719bSwdenk  autostart	- if set to "yes", an image loaded using the "bootp",
3899c609719bSwdenk		  "rarpboot", "tftpboot" or "diskboot" commands will
3900c609719bSwdenk		  be automatically started (by internally calling
3901c609719bSwdenk		  "bootm")
3902c609719bSwdenk
39034a6fd34bSwdenk		  If set to "no", a standalone image passed to the
39044a6fd34bSwdenk		  "bootm" command will be copied to the load address
39054a6fd34bSwdenk		  (and eventually uncompressed), but NOT be started.
39064a6fd34bSwdenk		  This can be used to load and uncompress arbitrary
39074a6fd34bSwdenk		  data.
39084a6fd34bSwdenk
3909a28afca5SDavid A. Long  fdt_high	- if set this restricts the maximum address that the
3910a28afca5SDavid A. Long		  flattened device tree will be copied into upon boot.
3911fa34f6b2SShawn Guo		  For example, if you have a system with 1 GB memory
3912fa34f6b2SShawn Guo		  at physical address 0x10000000, while Linux kernel
3913fa34f6b2SShawn Guo		  only recognizes the first 704 MB as low memory, you
3914fa34f6b2SShawn Guo		  may need to set fdt_high as 0x3C000000 to have the
3915fa34f6b2SShawn Guo		  device tree blob be copied to the maximum address
3916fa34f6b2SShawn Guo		  of the 704 MB low memory, so that Linux kernel can
3917fa34f6b2SShawn Guo		  access it during the boot procedure.
3918fa34f6b2SShawn Guo
3919a28afca5SDavid A. Long		  If this is set to the special value 0xFFFFFFFF then
3920a28afca5SDavid A. Long		  the fdt will not be copied at all on boot.  For this
3921a28afca5SDavid A. Long		  to work it must reside in writable memory, have
3922a28afca5SDavid A. Long		  sufficient padding on the end of it for u-boot to
3923a28afca5SDavid A. Long		  add the information it needs into it, and the memory
3924a28afca5SDavid A. Long		  must be accessible by the kernel.
3925a28afca5SDavid A. Long
3926eea63e05SSimon Glass  fdtcontroladdr- if set this is the address of the control flattened
3927eea63e05SSimon Glass		  device tree used by U-Boot when CONFIG_OF_CONTROL is
3928eea63e05SSimon Glass		  defined.
3929eea63e05SSimon Glass
393017ea1177Swdenk  i2cfast	- (PPC405GP|PPC405EP only)
393117ea1177Swdenk		  if set to 'y' configures Linux I2C driver for fast
393217ea1177Swdenk		  mode (400kHZ). This environment variable is used in
393317ea1177Swdenk		  initialization code. So, for changes to be effective
393417ea1177Swdenk		  it must be saved and board must be reset.
393517ea1177Swdenk
3936c609719bSwdenk  initrd_high	- restrict positioning of initrd images:
3937c609719bSwdenk		  If this variable is not set, initrd images will be
3938c609719bSwdenk		  copied to the highest possible address in RAM; this
3939c609719bSwdenk		  is usually what you want since it allows for
3940c609719bSwdenk		  maximum initrd size. If for some reason you want to
3941c609719bSwdenk		  make sure that the initrd image is loaded below the
39426d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		  CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3943c609719bSwdenk		  variable to a value of "no" or "off" or "0".
3944c609719bSwdenk		  Alternatively, you can set it to a maximum upper
3945c609719bSwdenk		  address to use (U-Boot will still check that it
3946c609719bSwdenk		  does not overwrite the U-Boot stack and data).
3947c609719bSwdenk
3948c609719bSwdenk		  For instance, when you have a system with 16 MB
39497152b1d0Swdenk		  RAM, and want to reserve 4 MB from use by Linux,
3950c609719bSwdenk		  you can do this by adding "mem=12M" to the value of
3951c609719bSwdenk		  the "bootargs" variable. However, now you must make
39527152b1d0Swdenk		  sure that the initrd image is placed in the first
3953c609719bSwdenk		  12 MB as well - this can be done with
3954c609719bSwdenk
3955c609719bSwdenk		  setenv initrd_high 00c00000
3956c609719bSwdenk
395738b99261Swdenk		  If you set initrd_high to 0xFFFFFFFF, this is an
395838b99261Swdenk		  indication to U-Boot that all addresses are legal
395938b99261Swdenk		  for the Linux kernel, including addresses in flash
396038b99261Swdenk		  memory. In this case U-Boot will NOT COPY the
396138b99261Swdenk		  ramdisk at all. This may be useful to reduce the
396238b99261Swdenk		  boot time on your system, but requires that this
396338b99261Swdenk		  feature is supported by your Linux kernel.
396438b99261Swdenk
3965c609719bSwdenk  ipaddr	- IP address; needed for tftpboot command
3966c609719bSwdenk
3967c609719bSwdenk  loadaddr	- Default load address for commands like "bootp",
3968dc7c9a1aSwdenk		  "rarpboot", "tftpboot", "loadb" or "diskboot"
3969c609719bSwdenk
3970c609719bSwdenk  loads_echo	- see CONFIG_LOADS_ECHO
3971c609719bSwdenk
3972c609719bSwdenk  serverip	- TFTP server IP address; needed for tftpboot command
3973c609719bSwdenk
3974c609719bSwdenk  bootretry	- see CONFIG_BOOT_RETRY_TIME
3975c609719bSwdenk
3976c609719bSwdenk  bootdelaykey	- see CONFIG_AUTOBOOT_DELAY_STR
3977c609719bSwdenk
3978c609719bSwdenk  bootstopkey	- see CONFIG_AUTOBOOT_STOP_STR
3979c609719bSwdenk
3980e2a53458SMike Frysinger  ethprime	- controls which interface is used first.
3981a3d991bdSwdenk
3982e2a53458SMike Frysinger  ethact	- controls which interface is currently active.
3983e2a53458SMike Frysinger		  For example you can do the following
3984a3d991bdSwdenk
398548690d80SHeiko Schocher		  => setenv ethact FEC
398648690d80SHeiko Schocher		  => ping 192.168.0.1 # traffic sent on FEC
398748690d80SHeiko Schocher		  => setenv ethact SCC
398848690d80SHeiko Schocher		  => ping 10.0.0.1 # traffic sent on SCC
3989a3d991bdSwdenk
3990e1692577SMatthias Fuchs  ethrotate	- When set to "no" U-Boot does not go through all
3991e1692577SMatthias Fuchs		  available network interfaces.
3992e1692577SMatthias Fuchs		  It just stays at the currently selected interface.
3993e1692577SMatthias Fuchs
3994a3d991bdSwdenk  netretry	- When set to "no" each network operation will
3995a3d991bdSwdenk		  either succeed or fail without retrying.
39966e592385Swdenk		  When set to "once" the network operation will
39976e592385Swdenk		  fail when all the available network interfaces
39986e592385Swdenk		  are tried once without success.
3999a3d991bdSwdenk		  Useful on scripts which control the retry operation
4000a3d991bdSwdenk		  themselves.
4001a3d991bdSwdenk
4002b4e2f89dSJean-Christophe PLAGNIOL-VILLARD  npe_ucode	- set load address for the NPE microcode
4003a1cf027aSJean-Christophe PLAGNIOL-VILLARD
4004b445bbb4SJeremiah Mahler  silent_linux  - If set then Linux will be told to boot silently, by
40058d51aacdSSimon Glass		  changing the console to be empty. If "yes" it will be
40068d51aacdSSimon Glass		  made silent. If "no" it will not be made silent. If
40078d51aacdSSimon Glass		  unset, then it will be made silent if the U-Boot console
40088d51aacdSSimon Glass		  is silent.
40098d51aacdSSimon Glass
4010f5fb7346SAlbert ARIBAUD \(3ADEV\)  tftpsrcp	- If this is set, the value is used for TFTP's
4011ecb0ccd9SWolfgang Denk		  UDP source port.
4012ecb0ccd9SWolfgang Denk
4013f5fb7346SAlbert ARIBAUD \(3ADEV\)  tftpdstp	- If this is set, the value is used for TFTP's UDP
401428cb9375SWolfgang Denk		  destination port instead of the Well Know Port 69.
401528cb9375SWolfgang Denk
4016c96f86eeSWolfgang Denk  tftpblocksize - Block size to use for TFTP transfers; if not set,
4017c96f86eeSWolfgang Denk		  we use the TFTP server's default block size
4018c96f86eeSWolfgang Denk
4019c96f86eeSWolfgang Denk  tftptimeout	- Retransmission timeout for TFTP packets (in milli-
4020c96f86eeSWolfgang Denk		  seconds, minimum value is 1000 = 1 second). Defines
4021c96f86eeSWolfgang Denk		  when a packet is considered to be lost so it has to
4022c96f86eeSWolfgang Denk		  be retransmitted. The default is 5000 = 5 seconds.
4023c96f86eeSWolfgang Denk		  Lowering this value may make downloads succeed
4024c96f86eeSWolfgang Denk		  faster in networks with high packet loss rates or
4025c96f86eeSWolfgang Denk		  with unreliable TFTP servers.
4026c96f86eeSWolfgang Denk
4027f5fb7346SAlbert ARIBAUD \(3ADEV\)  tftptimeoutcountmax	- maximum count of TFTP timeouts (no
4028f5fb7346SAlbert ARIBAUD \(3ADEV\)		  unit, minimum value = 0). Defines how many timeouts
4029f5fb7346SAlbert ARIBAUD \(3ADEV\)		  can happen during a single file transfer before that
4030f5fb7346SAlbert ARIBAUD \(3ADEV\)		  transfer is aborted. The default is 10, and 0 means
4031f5fb7346SAlbert ARIBAUD \(3ADEV\)		  'no timeouts allowed'. Increasing this value may help
4032f5fb7346SAlbert ARIBAUD \(3ADEV\)		  downloads succeed with high packet loss rates, or with
4033f5fb7346SAlbert ARIBAUD \(3ADEV\)		  unreliable TFTP servers or client hardware.
4034f5fb7346SAlbert ARIBAUD \(3ADEV\)
4035a3d991bdSwdenk  vlan		- When set to a value < 4095 the traffic over
403611ccc33fSMarcel Ziswiler		  Ethernet is encapsulated/received over 802.1q
4037a3d991bdSwdenk		  VLAN tagged frames.
4038c609719bSwdenk
403950768f5bSAlexandre Messier  bootpretryperiod	- Period during which BOOTP/DHCP sends retries.
404050768f5bSAlexandre Messier		  Unsigned value, in milliseconds. If not set, the period will
404150768f5bSAlexandre Messier		  be either the default (28000), or a value based on
404250768f5bSAlexandre Messier		  CONFIG_NET_RETRY_COUNT, if defined. This value has
404350768f5bSAlexandre Messier		  precedence over the valu based on CONFIG_NET_RETRY_COUNT.
404450768f5bSAlexandre Messier
4045dc0b7b0eSJason HobbsThe following image location variables contain the location of images
4046dc0b7b0eSJason Hobbsused in booting. The "Image" column gives the role of the image and is
4047dc0b7b0eSJason Hobbsnot an environment variable name. The other columns are environment
4048dc0b7b0eSJason Hobbsvariable names. "File Name" gives the name of the file on a TFTP
4049dc0b7b0eSJason Hobbsserver, "RAM Address" gives the location in RAM the image will be
4050dc0b7b0eSJason Hobbsloaded to, and "Flash Location" gives the image's address in NOR
4051dc0b7b0eSJason Hobbsflash or offset in NAND flash.
4052dc0b7b0eSJason Hobbs
4053dc0b7b0eSJason Hobbs*Note* - these variables don't have to be defined for all boards, some
4054aed9fed9SFabio Estevamboards currently use other variables for these purposes, and some
4055dc0b7b0eSJason Hobbsboards use these variables for other purposes.
4056dc0b7b0eSJason Hobbs
4057dc0b7b0eSJason HobbsImage		    File Name	     RAM Address       Flash Location
4058dc0b7b0eSJason Hobbs-----		    ---------	     -----------       --------------
4059dc0b7b0eSJason Hobbsu-boot		    u-boot	     u-boot_addr_r     u-boot_addr
4060dc0b7b0eSJason HobbsLinux kernel	    bootfile	     kernel_addr_r     kernel_addr
4061dc0b7b0eSJason Hobbsdevice tree blob    fdtfile	     fdt_addr_r	       fdt_addr
4062dc0b7b0eSJason Hobbsramdisk		    ramdiskfile	     ramdisk_addr_r    ramdisk_addr
4063dc0b7b0eSJason Hobbs
4064c609719bSwdenkThe following environment variables may be used and automatically
4065c609719bSwdenkupdated by the network boot commands ("bootp" and "rarpboot"),
4066c609719bSwdenkdepending the information provided by your boot server:
4067c609719bSwdenk
4068c609719bSwdenk  bootfile	- see above
4069c609719bSwdenk  dnsip		- IP address of your Domain Name Server
4070fe389a82Sstroese  dnsip2	- IP address of your secondary Domain Name Server
4071c609719bSwdenk  gatewayip	- IP address of the Gateway (Router) to use
4072c609719bSwdenk  hostname	- Target hostname
4073c609719bSwdenk  ipaddr	- see above
4074c609719bSwdenk  netmask	- Subnet Mask
4075c609719bSwdenk  rootpath	- Pathname of the root filesystem on the NFS server
4076c609719bSwdenk  serverip	- see above
4077c609719bSwdenk
4078c609719bSwdenk
4079c609719bSwdenkThere are two special Environment Variables:
4080c609719bSwdenk
4081c609719bSwdenk  serial#	- contains hardware identification information such
4082c609719bSwdenk		  as type string and/or serial number
4083c609719bSwdenk  ethaddr	- Ethernet address
4084c609719bSwdenk
4085c609719bSwdenkThese variables can be set only once (usually during manufacturing of
4086c609719bSwdenkthe board). U-Boot refuses to delete or overwrite these variables
4087c609719bSwdenkonce they have been set once.
4088c609719bSwdenk
4089c609719bSwdenk
4090c1551ea8SstroeseFurther special Environment Variables:
4091c1551ea8Sstroese
4092c1551ea8Sstroese  ver		- Contains the U-Boot version string as printed
4093c1551ea8Sstroese		  with the "version" command. This variable is
4094c1551ea8Sstroese		  readonly (see CONFIG_VERSION_VARIABLE).
4095c1551ea8Sstroese
4096c1551ea8Sstroese
4097c609719bSwdenkPlease note that changes to some configuration parameters may take
4098c609719bSwdenkonly effect after the next boot (yes, that's just like Windoze :-).
4099c609719bSwdenk
4100c609719bSwdenk
4101170ab110SJoe HershbergerCallback functions for environment variables:
4102170ab110SJoe Hershberger---------------------------------------------
4103170ab110SJoe Hershberger
4104170ab110SJoe HershbergerFor some environment variables, the behavior of u-boot needs to change
4105b445bbb4SJeremiah Mahlerwhen their values are changed.  This functionality allows functions to
4106170ab110SJoe Hershbergerbe associated with arbitrary variables.  On creation, overwrite, or
4107170ab110SJoe Hershbergerdeletion, the callback will provide the opportunity for some side
4108170ab110SJoe Hershbergereffect to happen or for the change to be rejected.
4109170ab110SJoe Hershberger
4110170ab110SJoe HershbergerThe callbacks are named and associated with a function using the
4111170ab110SJoe HershbergerU_BOOT_ENV_CALLBACK macro in your board or driver code.
4112170ab110SJoe Hershberger
4113170ab110SJoe HershbergerThese callbacks are associated with variables in one of two ways.  The
4114170ab110SJoe Hershbergerstatic list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4115170ab110SJoe Hershbergerin the board configuration to a string that defines a list of
4116170ab110SJoe Hershbergerassociations.  The list must be in the following format:
4117170ab110SJoe Hershberger
4118170ab110SJoe Hershberger	entry = variable_name[:callback_name]
4119170ab110SJoe Hershberger	list = entry[,list]
4120170ab110SJoe Hershberger
4121170ab110SJoe HershbergerIf the callback name is not specified, then the callback is deleted.
4122170ab110SJoe HershbergerSpaces are also allowed anywhere in the list.
4123170ab110SJoe Hershberger
4124170ab110SJoe HershbergerCallbacks can also be associated by defining the ".callbacks" variable
4125170ab110SJoe Hershbergerwith the same list format above.  Any association in ".callbacks" will
4126170ab110SJoe Hershbergeroverride any association in the static list. You can define
4127170ab110SJoe HershbergerCONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4128b445bbb4SJeremiah Mahler".callbacks" environment variable in the default or embedded environment.
4129170ab110SJoe Hershberger
4130bdf1fe4eSJoe HershbergerIf CONFIG_REGEX is defined, the variable_name above is evaluated as a
4131bdf1fe4eSJoe Hershbergerregular expression. This allows multiple variables to be connected to
4132bdf1fe4eSJoe Hershbergerthe same callback without explicitly listing them all out.
4133bdf1fe4eSJoe Hershberger
4134170ab110SJoe Hershberger
4135f07771ccSwdenkCommand Line Parsing:
4136f07771ccSwdenk=====================
4137f07771ccSwdenk
4138f07771ccSwdenkThere are two different command line parsers available with U-Boot:
41397152b1d0Swdenkthe old "simple" one, and the much more powerful "hush" shell:
4140f07771ccSwdenk
4141f07771ccSwdenkOld, simple command line parser:
4142f07771ccSwdenk--------------------------------
4143f07771ccSwdenk
4144f07771ccSwdenk- supports environment variables (through setenv / saveenv commands)
4145f07771ccSwdenk- several commands on one line, separated by ';'
4146fe126d8bSWolfgang Denk- variable substitution using "... ${name} ..." syntax
4147f07771ccSwdenk- special characters ('$', ';') can be escaped by prefixing with '\',
4148f07771ccSwdenk  for example:
4149fe126d8bSWolfgang Denk	setenv bootcmd bootm \${address}
4150f07771ccSwdenk- You can also escape text by enclosing in single apostrophes, for example:
4151f07771ccSwdenk	setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4152f07771ccSwdenk
4153f07771ccSwdenkHush shell:
4154f07771ccSwdenk-----------
4155f07771ccSwdenk
4156f07771ccSwdenk- similar to Bourne shell, with control structures like
4157f07771ccSwdenk  if...then...else...fi, for...do...done; while...do...done,
4158f07771ccSwdenk  until...do...done, ...
4159f07771ccSwdenk- supports environment ("global") variables (through setenv / saveenv
4160f07771ccSwdenk  commands) and local shell variables (through standard shell syntax
4161f07771ccSwdenk  "name=value"); only environment variables can be used with "run"
4162f07771ccSwdenk  command
4163f07771ccSwdenk
4164f07771ccSwdenkGeneral rules:
4165f07771ccSwdenk--------------
4166f07771ccSwdenk
4167f07771ccSwdenk(1) If a command line (or an environment variable executed by a "run"
4168f07771ccSwdenk    command) contains several commands separated by semicolon, and
4169f07771ccSwdenk    one of these commands fails, then the remaining commands will be
4170f07771ccSwdenk    executed anyway.
4171f07771ccSwdenk
4172f07771ccSwdenk(2) If you execute several variables with one call to run (i. e.
417311ccc33fSMarcel Ziswiler    calling run with a list of variables as arguments), any failing
4174f07771ccSwdenk    command will cause "run" to terminate, i. e. the remaining
4175f07771ccSwdenk    variables are not executed.
4176f07771ccSwdenk
4177c609719bSwdenkNote for Redundant Ethernet Interfaces:
4178c609719bSwdenk=======================================
4179c609719bSwdenk
418011ccc33fSMarcel ZiswilerSome boards come with redundant Ethernet interfaces; U-Boot supports
4181c609719bSwdenksuch configurations and is capable of automatic selection of a
41827152b1d0Swdenk"working" interface when needed. MAC assignment works as follows:
4183c609719bSwdenk
4184c609719bSwdenkNetwork interfaces are numbered eth0, eth1, eth2, ... Corresponding
4185c609719bSwdenkMAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4186c609719bSwdenk"eth1addr" (=>eth1), "eth2addr", ...
4187c609719bSwdenk
4188c609719bSwdenkIf the network interface stores some valid MAC address (for instance
4189c609719bSwdenkin SROM), this is used as default address if there is NO correspon-
4190c609719bSwdenkding setting in the environment; if the corresponding environment
4191c609719bSwdenkvariable is set, this overrides the settings in the card; that means:
4192c609719bSwdenk
4193c609719bSwdenko If the SROM has a valid MAC address, and there is no address in the
4194c609719bSwdenk  environment, the SROM's address is used.
4195c609719bSwdenk
4196c609719bSwdenko If there is no valid address in the SROM, and a definition in the
4197c609719bSwdenk  environment exists, then the value from the environment variable is
4198c609719bSwdenk  used.
4199c609719bSwdenk
4200c609719bSwdenko If both the SROM and the environment contain a MAC address, and
4201c609719bSwdenk  both addresses are the same, this MAC address is used.
4202c609719bSwdenk
4203c609719bSwdenko If both the SROM and the environment contain a MAC address, and the
4204c609719bSwdenk  addresses differ, the value from the environment is used and a
4205c609719bSwdenk  warning is printed.
4206c609719bSwdenk
4207c609719bSwdenko If neither SROM nor the environment contain a MAC address, an error
4208bef1014bSJoe Hershberger  is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
4209bef1014bSJoe Hershberger  a random, locally-assigned MAC is used.
4210c609719bSwdenk
4211ecee9324SBen WarrenIf Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4212ecee9324SBen Warrenwill be programmed into hardware as part of the initialization process.	 This
4213ecee9324SBen Warrenmay be skipped by setting the appropriate 'ethmacskip' environment variable.
4214ecee9324SBen WarrenThe naming convention is as follows:
4215ecee9324SBen Warren"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4216c609719bSwdenk
4217c609719bSwdenkImage Formats:
4218c609719bSwdenk==============
4219c609719bSwdenk
42203310c549SMarian BalakowiczU-Boot is capable of booting (and performing other auxiliary operations on)
42213310c549SMarian Balakowiczimages in two formats:
42223310c549SMarian Balakowicz
42233310c549SMarian BalakowiczNew uImage format (FIT)
42243310c549SMarian Balakowicz-----------------------
42253310c549SMarian Balakowicz
42263310c549SMarian BalakowiczFlexible and powerful format based on Flattened Image Tree -- FIT (similar
42273310c549SMarian Balakowiczto Flattened Device Tree). It allows the use of images with multiple
42283310c549SMarian Balakowiczcomponents (several kernels, ramdisks, etc.), with contents protected by
42293310c549SMarian BalakowiczSHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
42303310c549SMarian Balakowicz
42313310c549SMarian Balakowicz
42323310c549SMarian BalakowiczOld uImage format
42333310c549SMarian Balakowicz-----------------
42343310c549SMarian Balakowicz
42353310c549SMarian BalakowiczOld image format is based on binary files which can be basically anything,
42363310c549SMarian Balakowiczpreceded by a special header; see the definitions in include/image.h for
42373310c549SMarian Balakowiczdetails; basically, the header defines the following image properties:
4238c609719bSwdenk
4239c609719bSwdenk* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4240c609719bSwdenk  4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4241f5ed9e39SPeter Tyser  LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4242f5ed9e39SPeter Tyser  Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4243f5ed9e39SPeter Tyser  INTEGRITY).
4244daab59acSAndy Shevchenko* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
4245afc1ce82SMacpaul Lin  IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4246daab59acSAndy Shevchenko  Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4247c29fdfc1Swdenk* Compression Type (uncompressed, gzip, bzip2)
4248c609719bSwdenk* Load Address
4249c609719bSwdenk* Entry Point
4250c609719bSwdenk* Image Name
4251c609719bSwdenk* Image Timestamp
4252c609719bSwdenk
4253c609719bSwdenkThe header is marked by a special Magic Number, and both the header
4254c609719bSwdenkand the data portions of the image are secured against corruption by
4255c609719bSwdenkCRC32 checksums.
4256c609719bSwdenk
4257c609719bSwdenk
4258c609719bSwdenkLinux Support:
4259c609719bSwdenk==============
4260c609719bSwdenk
4261c609719bSwdenkAlthough U-Boot should support any OS or standalone application
42627152b1d0Swdenkeasily, the main focus has always been on Linux during the design of
4263c609719bSwdenkU-Boot.
4264c609719bSwdenk
4265c609719bSwdenkU-Boot includes many features that so far have been part of some
4266c609719bSwdenkspecial "boot loader" code within the Linux kernel. Also, any
4267c609719bSwdenk"initrd" images to be used are no longer part of one big Linux image;
4268c609719bSwdenkinstead, kernel and "initrd" are separate images. This implementation
42697152b1d0Swdenkserves several purposes:
4270c609719bSwdenk
4271c609719bSwdenk- the same features can be used for other OS or standalone
4272c609719bSwdenk  applications (for instance: using compressed images to reduce the
4273c609719bSwdenk  Flash memory footprint)
4274c609719bSwdenk
4275c609719bSwdenk- it becomes much easier to port new Linux kernel versions because
42767152b1d0Swdenk  lots of low-level, hardware dependent stuff are done by U-Boot
4277c609719bSwdenk
4278c609719bSwdenk- the same Linux kernel image can now be used with different "initrd"
4279c609719bSwdenk  images; of course this also means that different kernel images can
4280c609719bSwdenk  be run with the same "initrd". This makes testing easier (you don't
4281c609719bSwdenk  have to build a new "zImage.initrd" Linux image when you just
4282c609719bSwdenk  change a file in your "initrd"). Also, a field-upgrade of the
4283c609719bSwdenk  software is easier now.
4284c609719bSwdenk
4285c609719bSwdenk
4286c609719bSwdenkLinux HOWTO:
4287c609719bSwdenk============
4288c609719bSwdenk
4289c609719bSwdenkPorting Linux to U-Boot based systems:
4290c609719bSwdenk---------------------------------------
4291c609719bSwdenk
4292c609719bSwdenkU-Boot cannot save you from doing all the necessary modifications to
4293c609719bSwdenkconfigure the Linux device drivers for use with your target hardware
4294c609719bSwdenk(no, we don't intend to provide a full virtual machine interface to
4295c609719bSwdenkLinux :-).
4296c609719bSwdenk
4297a47a12beSStefan RoeseBut now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4298c609719bSwdenk
4299c609719bSwdenkJust make sure your machine specific header file (for instance
4300c609719bSwdenkinclude/asm-ppc/tqm8xx.h) includes the same definition of the Board
43011dc30693SMarkus HeidelbergInformation structure as we define in include/asm-<arch>/u-boot.h,
43021dc30693SMarkus Heidelbergand make sure that your definition of IMAP_ADDR uses the same value
43036d0f6bcfSJean-Christophe PLAGNIOL-VILLARDas your U-Boot configuration in CONFIG_SYS_IMMR.
4304c609719bSwdenk
43052eb31b13SSimon GlassNote that U-Boot now has a driver model, a unified model for drivers.
43062eb31b13SSimon GlassIf you are adding a new driver, plumb it into driver model. If there
43072eb31b13SSimon Glassis no uclass available, you are encouraged to create one. See
43082eb31b13SSimon Glassdoc/driver-model.
43092eb31b13SSimon Glass
4310c609719bSwdenk
4311c609719bSwdenkConfiguring the Linux kernel:
4312c609719bSwdenk-----------------------------
4313c609719bSwdenk
4314c609719bSwdenkNo specific requirements for U-Boot. Make sure you have some root
4315c609719bSwdenkdevice (initial ramdisk, NFS) for your target system.
4316c609719bSwdenk
4317c609719bSwdenk
4318c609719bSwdenkBuilding a Linux Image:
4319c609719bSwdenk-----------------------
4320c609719bSwdenk
432124ee89b9SwdenkWith U-Boot, "normal" build targets like "zImage" or "bzImage" are
432224ee89b9Swdenknot used. If you use recent kernel source, a new build target
432324ee89b9Swdenk"uImage" will exist which automatically builds an image usable by
432424ee89b9SwdenkU-Boot. Most older kernels also have support for a "pImage" target,
432524ee89b9Swdenkwhich was introduced for our predecessor project PPCBoot and uses a
432624ee89b9Swdenk100% compatible format.
4327c609719bSwdenk
4328c609719bSwdenkExample:
4329c609719bSwdenk
4330ab584d67SHolger Freyther	make TQM850L_defconfig
4331c609719bSwdenk	make oldconfig
4332c609719bSwdenk	make dep
433324ee89b9Swdenk	make uImage
4334c609719bSwdenk
433524ee89b9SwdenkThe "uImage" build target uses a special tool (in 'tools/mkimage') to
433624ee89b9Swdenkencapsulate a compressed Linux kernel image with header	 information,
433724ee89b9SwdenkCRC32 checksum etc. for use with U-Boot. This is what we are doing:
4338c609719bSwdenk
433924ee89b9Swdenk* build a standard "vmlinux" kernel image (in ELF binary format):
434024ee89b9Swdenk
434124ee89b9Swdenk* convert the kernel into a raw binary image:
434224ee89b9Swdenk
434324ee89b9Swdenk	${CROSS_COMPILE}-objcopy -O binary \
434424ee89b9Swdenk				 -R .note -R .comment \
434524ee89b9Swdenk				 -S vmlinux linux.bin
434624ee89b9Swdenk
434724ee89b9Swdenk* compress the binary image:
434824ee89b9Swdenk
434924ee89b9Swdenk	gzip -9 linux.bin
435024ee89b9Swdenk
435124ee89b9Swdenk* package compressed binary image for U-Boot:
435224ee89b9Swdenk
435324ee89b9Swdenk	mkimage -A ppc -O linux -T kernel -C gzip \
435424ee89b9Swdenk		-a 0 -e 0 -n "Linux Kernel Image" \
435524ee89b9Swdenk		-d linux.bin.gz uImage
435624ee89b9Swdenk
435724ee89b9Swdenk
435824ee89b9SwdenkThe "mkimage" tool can also be used to create ramdisk images for use
435924ee89b9Swdenkwith U-Boot, either separated from the Linux kernel image, or
436024ee89b9Swdenkcombined into one file. "mkimage" encapsulates the images with a 64
436124ee89b9Swdenkbyte header containing information about target architecture,
436224ee89b9Swdenkoperating system, image type, compression method, entry points, time
436324ee89b9Swdenkstamp, CRC32 checksums, etc.
436424ee89b9Swdenk
436524ee89b9Swdenk"mkimage" can be called in two ways: to verify existing images and
436624ee89b9Swdenkprint the header information, or to build new images.
4367c609719bSwdenk
4368c609719bSwdenkIn the first form (with "-l" option) mkimage lists the information
4369c609719bSwdenkcontained in the header of an existing U-Boot image; this includes
4370c609719bSwdenkchecksum verification:
4371c609719bSwdenk
4372c609719bSwdenk	tools/mkimage -l image
4373c609719bSwdenk	  -l ==> list image header information
4374c609719bSwdenk
4375c609719bSwdenkThe second form (with "-d" option) is used to build a U-Boot image
4376c609719bSwdenkfrom a "data file" which is used as image payload:
4377c609719bSwdenk
4378c609719bSwdenk	tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4379c609719bSwdenk		      -n name -d data_file image
4380c609719bSwdenk	  -A ==> set architecture to 'arch'
4381c609719bSwdenk	  -O ==> set operating system to 'os'
4382c609719bSwdenk	  -T ==> set image type to 'type'
4383c609719bSwdenk	  -C ==> set compression type 'comp'
4384c609719bSwdenk	  -a ==> set load address to 'addr' (hex)
4385c609719bSwdenk	  -e ==> set entry point to 'ep' (hex)
4386c609719bSwdenk	  -n ==> set image name to 'name'
4387c609719bSwdenk	  -d ==> use image data from 'datafile'
4388c609719bSwdenk
438969459791SwdenkRight now, all Linux kernels for PowerPC systems use the same load
439069459791Swdenkaddress (0x00000000), but the entry point address depends on the
439169459791Swdenkkernel version:
4392c609719bSwdenk
4393c609719bSwdenk- 2.2.x kernels have the entry point at 0x0000000C,
439424ee89b9Swdenk- 2.3.x and later kernels have the entry point at 0x00000000.
4395c609719bSwdenk
4396c609719bSwdenkSo a typical call to build a U-Boot image would read:
4397c609719bSwdenk
439824ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
439924ee89b9Swdenk	> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4400a47a12beSStefan Roese	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
440124ee89b9Swdenk	> examples/uImage.TQM850L
440224ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4403c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4404c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
4405c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
4406c609719bSwdenk	Load Address: 0x00000000
440724ee89b9Swdenk	Entry Point:  0x00000000
4408c609719bSwdenk
4409c609719bSwdenkTo verify the contents of the image (or check for corruption):
4410c609719bSwdenk
441124ee89b9Swdenk	-> tools/mkimage -l examples/uImage.TQM850L
441224ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4413c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4414c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
4415c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
4416c609719bSwdenk	Load Address: 0x00000000
441724ee89b9Swdenk	Entry Point:  0x00000000
4418c609719bSwdenk
4419c609719bSwdenkNOTE: for embedded systems where boot time is critical you can trade
4420c609719bSwdenkspeed for memory and install an UNCOMPRESSED image instead: this
4421c609719bSwdenkneeds more space in Flash, but boots much faster since it does not
4422c609719bSwdenkneed to be uncompressed:
4423c609719bSwdenk
4424a47a12beSStefan Roese	-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
442524ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
442624ee89b9Swdenk	> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4427a47a12beSStefan Roese	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
442824ee89b9Swdenk	> examples/uImage.TQM850L-uncompressed
442924ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4430c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4431c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (uncompressed)
4432c609719bSwdenk	Data Size:    792160 Bytes = 773.59 kB = 0.76 MB
4433c609719bSwdenk	Load Address: 0x00000000
443424ee89b9Swdenk	Entry Point:  0x00000000
4435c609719bSwdenk
4436c609719bSwdenk
4437c609719bSwdenkSimilar you can build U-Boot images from a 'ramdisk.image.gz' file
4438c609719bSwdenkwhen your kernel is intended to use an initial ramdisk:
4439c609719bSwdenk
4440c609719bSwdenk	-> tools/mkimage -n 'Simple Ramdisk Image' \
4441c609719bSwdenk	> -A ppc -O linux -T ramdisk -C gzip \
4442c609719bSwdenk	> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4443c609719bSwdenk	Image Name:   Simple Ramdisk Image
4444c609719bSwdenk	Created:      Wed Jan 12 14:01:50 2000
4445c609719bSwdenk	Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
4446c609719bSwdenk	Data Size:    566530 Bytes = 553.25 kB = 0.54 MB
4447c609719bSwdenk	Load Address: 0x00000000
4448c609719bSwdenk	Entry Point:  0x00000000
4449c609719bSwdenk
4450a804b5ceSGuilherme Maciel FerreiraThe "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
4451a804b5ceSGuilherme Maciel Ferreiraoption performs the converse operation of the mkimage's second form (the "-d"
4452a804b5ceSGuilherme Maciel Ferreiraoption). Given an image built by mkimage, the dumpimage extracts a "data file"
4453a804b5ceSGuilherme Maciel Ferreirafrom the image:
4454a804b5ceSGuilherme Maciel Ferreira
4455f41f5b7cSGuilherme Maciel Ferreira	tools/dumpimage -i image -T type -p position data_file
4456f41f5b7cSGuilherme Maciel Ferreira	  -i ==> extract from the 'image' a specific 'data_file'
4457f41f5b7cSGuilherme Maciel Ferreira	  -T ==> set image type to 'type'
4458f41f5b7cSGuilherme Maciel Ferreira	  -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
4459a804b5ceSGuilherme Maciel Ferreira
4460c609719bSwdenk
4461c609719bSwdenkInstalling a Linux Image:
4462c609719bSwdenk-------------------------
4463c609719bSwdenk
4464c609719bSwdenkTo downloading a U-Boot image over the serial (console) interface,
4465c609719bSwdenkyou must convert the image to S-Record format:
4466c609719bSwdenk
4467c609719bSwdenk	objcopy -I binary -O srec examples/image examples/image.srec
4468c609719bSwdenk
4469c609719bSwdenkThe 'objcopy' does not understand the information in the U-Boot
4470c609719bSwdenkimage header, so the resulting S-Record file will be relative to
4471c609719bSwdenkaddress 0x00000000. To load it to a given address, you need to
4472c609719bSwdenkspecify the target address as 'offset' parameter with the 'loads'
4473c609719bSwdenkcommand.
4474c609719bSwdenk
4475c609719bSwdenkExample: install the image to address 0x40100000 (which on the
4476c609719bSwdenkTQM8xxL is in the first Flash bank):
4477c609719bSwdenk
4478c609719bSwdenk	=> erase 40100000 401FFFFF
4479c609719bSwdenk
4480c609719bSwdenk	.......... done
4481c609719bSwdenk	Erased 8 sectors
4482c609719bSwdenk
4483c609719bSwdenk	=> loads 40100000
4484c609719bSwdenk	## Ready for S-Record download ...
4485c609719bSwdenk	~>examples/image.srec
4486c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4487c609719bSwdenk	...
4488c609719bSwdenk	15989 15990 15991 15992
4489c609719bSwdenk	[file transfer complete]
4490c609719bSwdenk	[connected]
4491c609719bSwdenk	## Start Addr = 0x00000000
4492c609719bSwdenk
4493c609719bSwdenk
4494c609719bSwdenkYou can check the success of the download using the 'iminfo' command;
4495c609719bSwdenkthis includes a checksum verification so you can be sure no data
4496c609719bSwdenkcorruption happened:
4497c609719bSwdenk
4498c609719bSwdenk	=> imi 40100000
4499c609719bSwdenk
4500c609719bSwdenk	## Checking Image at 40100000 ...
4501c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4502c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4503c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4504c609719bSwdenk	   Load Address: 00000000
4505c609719bSwdenk	   Entry Point:	 0000000c
4506c609719bSwdenk	   Verifying Checksum ... OK
4507c609719bSwdenk
4508c609719bSwdenk
4509c609719bSwdenkBoot Linux:
4510c609719bSwdenk-----------
4511c609719bSwdenk
4512c609719bSwdenkThe "bootm" command is used to boot an application that is stored in
4513c609719bSwdenkmemory (RAM or Flash). In case of a Linux kernel image, the contents
4514c609719bSwdenkof the "bootargs" environment variable is passed to the kernel as
4515c609719bSwdenkparameters. You can check and modify this variable using the
4516c609719bSwdenk"printenv" and "setenv" commands:
4517c609719bSwdenk
4518c609719bSwdenk
4519c609719bSwdenk	=> printenv bootargs
4520c609719bSwdenk	bootargs=root=/dev/ram
4521c609719bSwdenk
4522c609719bSwdenk	=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4523c609719bSwdenk
4524c609719bSwdenk	=> printenv bootargs
4525c609719bSwdenk	bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4526c609719bSwdenk
4527c609719bSwdenk	=> bootm 40020000
4528c609719bSwdenk	## Booting Linux kernel at 40020000 ...
4529c609719bSwdenk	   Image Name:	 2.2.13 for NFS on TQM850L
4530c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4531c609719bSwdenk	   Data Size:	 381681 Bytes = 372 kB = 0 MB
4532c609719bSwdenk	   Load Address: 00000000
4533c609719bSwdenk	   Entry Point:	 0000000c
4534c609719bSwdenk	   Verifying Checksum ... OK
4535c609719bSwdenk	   Uncompressing Kernel Image ... OK
4536c609719bSwdenk	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
4537c609719bSwdenk	Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4538c609719bSwdenk	time_init: decrementer frequency = 187500000/60
4539c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
4540c609719bSwdenk	Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4541c609719bSwdenk	...
4542c609719bSwdenk
454311ccc33fSMarcel ZiswilerIf you want to boot a Linux kernel with initial RAM disk, you pass
45447152b1d0Swdenkthe memory addresses of both the kernel and the initrd image (PPBCOOT
4545c609719bSwdenkformat!) to the "bootm" command:
4546c609719bSwdenk
4547c609719bSwdenk	=> imi 40100000 40200000
4548c609719bSwdenk
4549c609719bSwdenk	## Checking Image at 40100000 ...
4550c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4551c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4552c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4553c609719bSwdenk	   Load Address: 00000000
4554c609719bSwdenk	   Entry Point:	 0000000c
4555c609719bSwdenk	   Verifying Checksum ... OK
4556c609719bSwdenk
4557c609719bSwdenk	## Checking Image at 40200000 ...
4558c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
4559c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
4560c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
4561c609719bSwdenk	   Load Address: 00000000
4562c609719bSwdenk	   Entry Point:	 00000000
4563c609719bSwdenk	   Verifying Checksum ... OK
4564c609719bSwdenk
4565c609719bSwdenk	=> bootm 40100000 40200000
4566c609719bSwdenk	## Booting Linux kernel at 40100000 ...
4567c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4568c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4569c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4570c609719bSwdenk	   Load Address: 00000000
4571c609719bSwdenk	   Entry Point:	 0000000c
4572c609719bSwdenk	   Verifying Checksum ... OK
4573c609719bSwdenk	   Uncompressing Kernel Image ... OK
4574c609719bSwdenk	## Loading RAMDisk Image at 40200000 ...
4575c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
4576c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
4577c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
4578c609719bSwdenk	   Load Address: 00000000
4579c609719bSwdenk	   Entry Point:	 00000000
4580c609719bSwdenk	   Verifying Checksum ... OK
4581c609719bSwdenk	   Loading Ramdisk ... OK
4582c609719bSwdenk	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
4583c609719bSwdenk	Boot arguments: root=/dev/ram
4584c609719bSwdenk	time_init: decrementer frequency = 187500000/60
4585c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
4586c609719bSwdenk	...
4587c609719bSwdenk	RAMDISK: Compressed image found at block 0
4588c609719bSwdenk	VFS: Mounted root (ext2 filesystem).
4589c609719bSwdenk
4590c609719bSwdenk	bash#
4591c609719bSwdenk
45920267768eSMatthew McClintockBoot Linux and pass a flat device tree:
45930267768eSMatthew McClintock-----------
45940267768eSMatthew McClintock
45950267768eSMatthew McClintockFirst, U-Boot must be compiled with the appropriate defines. See the section
45960267768eSMatthew McClintocktitled "Linux Kernel Interface" above for a more in depth explanation. The
45970267768eSMatthew McClintockfollowing is an example of how to start a kernel and pass an updated
45980267768eSMatthew McClintockflat device tree:
45990267768eSMatthew McClintock
46000267768eSMatthew McClintock=> print oftaddr
46010267768eSMatthew McClintockoftaddr=0x300000
46020267768eSMatthew McClintock=> print oft
46030267768eSMatthew McClintockoft=oftrees/mpc8540ads.dtb
46040267768eSMatthew McClintock=> tftp $oftaddr $oft
46050267768eSMatthew McClintockSpeed: 1000, full duplex
46060267768eSMatthew McClintockUsing TSEC0 device
46070267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.101
46080267768eSMatthew McClintockFilename 'oftrees/mpc8540ads.dtb'.
46090267768eSMatthew McClintockLoad address: 0x300000
46100267768eSMatthew McClintockLoading: #
46110267768eSMatthew McClintockdone
46120267768eSMatthew McClintockBytes transferred = 4106 (100a hex)
46130267768eSMatthew McClintock=> tftp $loadaddr $bootfile
46140267768eSMatthew McClintockSpeed: 1000, full duplex
46150267768eSMatthew McClintockUsing TSEC0 device
46160267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.2
46170267768eSMatthew McClintockFilename 'uImage'.
46180267768eSMatthew McClintockLoad address: 0x200000
46190267768eSMatthew McClintockLoading:############
46200267768eSMatthew McClintockdone
46210267768eSMatthew McClintockBytes transferred = 1029407 (fb51f hex)
46220267768eSMatthew McClintock=> print loadaddr
46230267768eSMatthew McClintockloadaddr=200000
46240267768eSMatthew McClintock=> print oftaddr
46250267768eSMatthew McClintockoftaddr=0x300000
46260267768eSMatthew McClintock=> bootm $loadaddr - $oftaddr
46270267768eSMatthew McClintock## Booting image at 00200000 ...
46280267768eSMatthew McClintock   Image Name:	 Linux-2.6.17-dirty
46290267768eSMatthew McClintock   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
46300267768eSMatthew McClintock   Data Size:	 1029343 Bytes = 1005.2 kB
46310267768eSMatthew McClintock   Load Address: 00000000
46320267768eSMatthew McClintock   Entry Point:	 00000000
46330267768eSMatthew McClintock   Verifying Checksum ... OK
46340267768eSMatthew McClintock   Uncompressing Kernel Image ... OK
46350267768eSMatthew McClintockBooting using flat device tree at 0x300000
46360267768eSMatthew McClintockUsing MPC85xx ADS machine description
46370267768eSMatthew McClintockMemory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
46380267768eSMatthew McClintock[snip]
46390267768eSMatthew McClintock
46400267768eSMatthew McClintock
46416069ff26SwdenkMore About U-Boot Image Types:
46426069ff26Swdenk------------------------------
46436069ff26Swdenk
46446069ff26SwdenkU-Boot supports the following image types:
46456069ff26Swdenk
46466069ff26Swdenk   "Standalone Programs" are directly runnable in the environment
46476069ff26Swdenk	provided by U-Boot; it is expected that (if they behave
46486069ff26Swdenk	well) you can continue to work in U-Boot after return from
46496069ff26Swdenk	the Standalone Program.
46506069ff26Swdenk   "OS Kernel Images" are usually images of some Embedded OS which
46516069ff26Swdenk	will take over control completely. Usually these programs
46526069ff26Swdenk	will install their own set of exception handlers, device
46536069ff26Swdenk	drivers, set up the MMU, etc. - this means, that you cannot
46546069ff26Swdenk	expect to re-enter U-Boot except by resetting the CPU.
46556069ff26Swdenk   "RAMDisk Images" are more or less just data blocks, and their
46566069ff26Swdenk	parameters (address, size) are passed to an OS kernel that is
46576069ff26Swdenk	being started.
46586069ff26Swdenk   "Multi-File Images" contain several images, typically an OS
46596069ff26Swdenk	(Linux) kernel image and one or more data images like
46606069ff26Swdenk	RAMDisks. This construct is useful for instance when you want
46616069ff26Swdenk	to boot over the network using BOOTP etc., where the boot
46626069ff26Swdenk	server provides just a single image file, but you want to get
46636069ff26Swdenk	for instance an OS kernel and a RAMDisk image.
46646069ff26Swdenk
46656069ff26Swdenk	"Multi-File Images" start with a list of image sizes, each
46666069ff26Swdenk	image size (in bytes) specified by an "uint32_t" in network
46676069ff26Swdenk	byte order. This list is terminated by an "(uint32_t)0".
46686069ff26Swdenk	Immediately after the terminating 0 follow the images, one by
46696069ff26Swdenk	one, all aligned on "uint32_t" boundaries (size rounded up to
46706069ff26Swdenk	a multiple of 4 bytes).
46716069ff26Swdenk
46726069ff26Swdenk   "Firmware Images" are binary images containing firmware (like
46736069ff26Swdenk	U-Boot or FPGA images) which usually will be programmed to
46746069ff26Swdenk	flash memory.
46756069ff26Swdenk
46766069ff26Swdenk   "Script files" are command sequences that will be executed by
46776069ff26Swdenk	U-Boot's command interpreter; this feature is especially
46786069ff26Swdenk	useful when you configure U-Boot to use a real shell (hush)
46796069ff26Swdenk	as command interpreter.
46806069ff26Swdenk
468144f074c7SMarek VasutBooting the Linux zImage:
468244f074c7SMarek Vasut-------------------------
468344f074c7SMarek Vasut
468444f074c7SMarek VasutOn some platforms, it's possible to boot Linux zImage. This is done
468544f074c7SMarek Vasutusing the "bootz" command. The syntax of "bootz" command is the same
468644f074c7SMarek Vasutas the syntax of "bootm" command.
468744f074c7SMarek Vasut
46888ac28563STom RiniNote, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
4689017e1f3fSMarek Vasutkernel with raw initrd images. The syntax is slightly different, the
4690017e1f3fSMarek Vasutaddress of the initrd must be augmented by it's size, in the following
4691017e1f3fSMarek Vasutformat: "<initrd addres>:<initrd size>".
4692017e1f3fSMarek Vasut
4693c609719bSwdenk
4694c609719bSwdenkStandalone HOWTO:
4695c609719bSwdenk=================
4696c609719bSwdenk
4697c609719bSwdenkOne of the features of U-Boot is that you can dynamically load and
4698c609719bSwdenkrun "standalone" applications, which can use some resources of
4699c609719bSwdenkU-Boot like console I/O functions or interrupt services.
4700c609719bSwdenk
4701c609719bSwdenkTwo simple examples are included with the sources:
4702c609719bSwdenk
4703c609719bSwdenk"Hello World" Demo:
4704c609719bSwdenk-------------------
4705c609719bSwdenk
4706c609719bSwdenk'examples/hello_world.c' contains a small "Hello World" Demo
4707c609719bSwdenkapplication; it is automatically compiled when you build U-Boot.
4708c609719bSwdenkIt's configured to run at address 0x00040004, so you can play with it
4709c609719bSwdenklike that:
4710c609719bSwdenk
4711c609719bSwdenk	=> loads
4712c609719bSwdenk	## Ready for S-Record download ...
4713c609719bSwdenk	~>examples/hello_world.srec
4714c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
4715c609719bSwdenk	[file transfer complete]
4716c609719bSwdenk	[connected]
4717c609719bSwdenk	## Start Addr = 0x00040004
4718c609719bSwdenk
4719c609719bSwdenk	=> go 40004 Hello World! This is a test.
4720c609719bSwdenk	## Starting application at 0x00040004 ...
4721c609719bSwdenk	Hello World
4722c609719bSwdenk	argc = 7
4723c609719bSwdenk	argv[0] = "40004"
4724c609719bSwdenk	argv[1] = "Hello"
4725c609719bSwdenk	argv[2] = "World!"
4726c609719bSwdenk	argv[3] = "This"
4727c609719bSwdenk	argv[4] = "is"
4728c609719bSwdenk	argv[5] = "a"
4729c609719bSwdenk	argv[6] = "test."
4730c609719bSwdenk	argv[7] = "<NULL>"
4731c609719bSwdenk	Hit any key to exit ...
4732c609719bSwdenk
4733c609719bSwdenk	## Application terminated, rc = 0x0
4734c609719bSwdenk
4735c609719bSwdenkAnother example, which demonstrates how to register a CPM interrupt
4736c609719bSwdenkhandler with the U-Boot code, can be found in 'examples/timer.c'.
4737c609719bSwdenkHere, a CPM timer is set up to generate an interrupt every second.
4738c609719bSwdenkThe interrupt service routine is trivial, just printing a '.'
4739c609719bSwdenkcharacter, but this is just a demo program. The application can be
4740c609719bSwdenkcontrolled by the following keys:
4741c609719bSwdenk
4742c609719bSwdenk	? - print current values og the CPM Timer registers
4743c609719bSwdenk	b - enable interrupts and start timer
4744c609719bSwdenk	e - stop timer and disable interrupts
4745c609719bSwdenk	q - quit application
4746c609719bSwdenk
4747c609719bSwdenk	=> loads
4748c609719bSwdenk	## Ready for S-Record download ...
4749c609719bSwdenk	~>examples/timer.srec
4750c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
4751c609719bSwdenk	[file transfer complete]
4752c609719bSwdenk	[connected]
4753c609719bSwdenk	## Start Addr = 0x00040004
4754c609719bSwdenk
4755c609719bSwdenk	=> go 40004
4756c609719bSwdenk	## Starting application at 0x00040004 ...
4757c609719bSwdenk	TIMERS=0xfff00980
4758c609719bSwdenk	Using timer 1
4759c609719bSwdenk	  tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4760c609719bSwdenk
4761c609719bSwdenkHit 'b':
4762c609719bSwdenk	[q, b, e, ?] Set interval 1000000 us
4763c609719bSwdenk	Enabling timer
4764c609719bSwdenkHit '?':
4765c609719bSwdenk	[q, b, e, ?] ........
4766c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4767c609719bSwdenkHit '?':
4768c609719bSwdenk	[q, b, e, ?] .
4769c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4770c609719bSwdenkHit '?':
4771c609719bSwdenk	[q, b, e, ?] .
4772c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4773c609719bSwdenkHit '?':
4774c609719bSwdenk	[q, b, e, ?] .
4775c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4776c609719bSwdenkHit 'e':
4777c609719bSwdenk	[q, b, e, ?] ...Stopping timer
4778c609719bSwdenkHit 'q':
4779c609719bSwdenk	[q, b, e, ?] ## Application terminated, rc = 0x0
4780c609719bSwdenk
4781c609719bSwdenk
478285ec0bccSwdenkMinicom warning:
478385ec0bccSwdenk================
478485ec0bccSwdenk
47857152b1d0SwdenkOver time, many people have reported problems when trying to use the
478685ec0bccSwdenk"minicom" terminal emulation program for serial download. I (wd)
478785ec0bccSwdenkconsider minicom to be broken, and recommend not to use it. Under
4788f07771ccSwdenkUnix, I recommend to use C-Kermit for general purpose use (and
478985ec0bccSwdenkespecially for kermit binary protocol download ("loadb" command), and
4790e53515a2SKarl O. Pincuse "cu" for S-Record download ("loads" command).  See
4791e53515a2SKarl O. Pinchttp://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4792e53515a2SKarl O. Pincfor help with kermit.
4793e53515a2SKarl O. Pinc
479485ec0bccSwdenk
479552f52c14SwdenkNevertheless, if you absolutely want to use it try adding this
479652f52c14Swdenkconfiguration to your "File transfer protocols" section:
479752f52c14Swdenk
479852f52c14Swdenk	   Name	   Program			Name U/D FullScr IO-Red. Multi
479952f52c14Swdenk	X  kermit  /usr/bin/kermit -i -l %l -s	 Y    U	   Y	   N	  N
480052f52c14Swdenk	Y  kermit  /usr/bin/kermit -i -l %l -r	 N    D	   Y	   N	  N
480152f52c14Swdenk
480252f52c14Swdenk
4803c609719bSwdenkNetBSD Notes:
4804c609719bSwdenk=============
4805c609719bSwdenk
4806c609719bSwdenkStarting at version 0.9.2, U-Boot supports NetBSD both as host
4807c609719bSwdenk(build U-Boot) and target system (boots NetBSD/mpc8xx).
4808c609719bSwdenk
4809c609719bSwdenkBuilding requires a cross environment; it is known to work on
4810c609719bSwdenkNetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4811c609719bSwdenkneed gmake since the Makefiles are not compatible with BSD make).
4812c609719bSwdenkNote that the cross-powerpc package does not install include files;
4813c609719bSwdenkattempting to build U-Boot will fail because <machine/ansi.h> is
4814c609719bSwdenkmissing.  This file has to be installed and patched manually:
4815c609719bSwdenk
4816c609719bSwdenk	# cd /usr/pkg/cross/powerpc-netbsd/include
4817c609719bSwdenk	# mkdir powerpc
4818c609719bSwdenk	# ln -s powerpc machine
4819c609719bSwdenk	# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4820c609719bSwdenk	# ${EDIT} powerpc/ansi.h	## must remove __va_list, _BSD_VA_LIST
4821c609719bSwdenk
4822c609719bSwdenkNative builds *don't* work due to incompatibilities between native
4823c609719bSwdenkand U-Boot include files.
4824c609719bSwdenk
4825c609719bSwdenkBooting assumes that (the first part of) the image booted is a
4826c609719bSwdenkstage-2 loader which in turn loads and then invokes the kernel
4827c609719bSwdenkproper. Loader sources will eventually appear in the NetBSD source
4828c609719bSwdenktree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
48292a8af187Swdenkmeantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4830c609719bSwdenk
4831c609719bSwdenk
4832c609719bSwdenkImplementation Internals:
4833c609719bSwdenk=========================
4834c609719bSwdenk
4835c609719bSwdenkThe following is not intended to be a complete description of every
4836c609719bSwdenkimplementation detail. However, it should help to understand the
4837c609719bSwdenkinner workings of U-Boot and make it easier to port it to custom
4838c609719bSwdenkhardware.
4839c609719bSwdenk
4840c609719bSwdenk
4841c609719bSwdenkInitial Stack, Global Data:
4842c609719bSwdenk---------------------------
4843c609719bSwdenk
4844c609719bSwdenkThe implementation of U-Boot is complicated by the fact that U-Boot
4845c609719bSwdenkstarts running out of ROM (flash memory), usually without access to
4846c609719bSwdenksystem RAM (because the memory controller is not initialized yet).
4847c609719bSwdenkThis means that we don't have writable Data or BSS segments, and BSS
4848c609719bSwdenkis not initialized as zero. To be able to get a C environment working
4849c609719bSwdenkat all, we have to allocate at least a minimal stack. Implementation
4850c609719bSwdenkoptions for this are defined and restricted by the CPU used: Some CPU
4851c609719bSwdenkmodels provide on-chip memory (like the IMMR area on MPC8xx and
4852c609719bSwdenkMPC826x processors), on others (parts of) the data cache can be
4853c609719bSwdenklocked as (mis-) used as memory, etc.
4854c609719bSwdenk
48557152b1d0Swdenk	Chris Hallinan posted a good summary of these issues to the
48560668236bSWolfgang Denk	U-Boot mailing list:
485743d9616cSwdenk
485843d9616cSwdenk	Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
485943d9616cSwdenk	From: "Chris Hallinan" <clh@net1plus.com>
486043d9616cSwdenk	Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
486143d9616cSwdenk	...
486243d9616cSwdenk
486343d9616cSwdenk	Correct me if I'm wrong, folks, but the way I understand it
486443d9616cSwdenk	is this: Using DCACHE as initial RAM for Stack, etc, does not
486543d9616cSwdenk	require any physical RAM backing up the cache. The cleverness
486643d9616cSwdenk	is that the cache is being used as a temporary supply of
486743d9616cSwdenk	necessary storage before the SDRAM controller is setup. It's
486811ccc33fSMarcel Ziswiler	beyond the scope of this list to explain the details, but you
486943d9616cSwdenk	can see how this works by studying the cache architecture and
487043d9616cSwdenk	operation in the architecture and processor-specific manuals.
487143d9616cSwdenk
487243d9616cSwdenk	OCM is On Chip Memory, which I believe the 405GP has 4K. It
487343d9616cSwdenk	is another option for the system designer to use as an
487411ccc33fSMarcel Ziswiler	initial stack/RAM area prior to SDRAM being available. Either
487543d9616cSwdenk	option should work for you. Using CS 4 should be fine if your
487643d9616cSwdenk	board designers haven't used it for something that would
487743d9616cSwdenk	cause you grief during the initial boot! It is frequently not
487843d9616cSwdenk	used.
487943d9616cSwdenk
48806d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
488143d9616cSwdenk	with your processor/board/system design. The default value
488243d9616cSwdenk	you will find in any recent u-boot distribution in
48838a316c9bSStefan Roese	walnut.h should work for you. I'd set it to a value larger
488443d9616cSwdenk	than your SDRAM module. If you have a 64MB SDRAM module, set
488543d9616cSwdenk	it above 400_0000. Just make sure your board has no resources
488643d9616cSwdenk	that are supposed to respond to that address! That code in
488743d9616cSwdenk	start.S has been around a while and should work as is when
488843d9616cSwdenk	you get the config right.
488943d9616cSwdenk
489043d9616cSwdenk	-Chris Hallinan
489143d9616cSwdenk	DS4.COM, Inc.
489243d9616cSwdenk
4893c609719bSwdenkIt is essential to remember this, since it has some impact on the C
4894c609719bSwdenkcode for the initialization procedures:
4895c609719bSwdenk
4896c609719bSwdenk* Initialized global data (data segment) is read-only. Do not attempt
4897c609719bSwdenk  to write it.
4898c609719bSwdenk
4899b445bbb4SJeremiah Mahler* Do not use any uninitialized global data (or implicitly initialized
4900c609719bSwdenk  as zero data - BSS segment) at all - this is undefined, initiali-
49017152b1d0Swdenk  zation is performed later (when relocating to RAM).
4902c609719bSwdenk
4903c609719bSwdenk* Stack space is very limited. Avoid big data buffers or things like
4904c609719bSwdenk  that.
4905c609719bSwdenk
4906c609719bSwdenkHaving only the stack as writable memory limits means we cannot use
4907b445bbb4SJeremiah Mahlernormal global data to share information between the code. But it
4908c609719bSwdenkturned out that the implementation of U-Boot can be greatly
4909c609719bSwdenksimplified by making a global data structure (gd_t) available to all
4910c609719bSwdenkfunctions. We could pass a pointer to this data as argument to _all_
4911c609719bSwdenkfunctions, but this would bloat the code. Instead we use a feature of
4912c609719bSwdenkthe GCC compiler (Global Register Variables) to share the data: we
4913c609719bSwdenkplace a pointer (gd) to the global data into a register which we
4914c609719bSwdenkreserve for this purpose.
4915c609719bSwdenk
49167152b1d0SwdenkWhen choosing a register for such a purpose we are restricted by the
4917c609719bSwdenkrelevant  (E)ABI  specifications for the current architecture, and by
4918c609719bSwdenkGCC's implementation.
4919c609719bSwdenk
4920c609719bSwdenkFor PowerPC, the following registers have specific use:
4921c609719bSwdenk	R1:	stack pointer
4922e7670f6cSWolfgang Denk	R2:	reserved for system use
4923c609719bSwdenk	R3-R4:	parameter passing and return values
4924c609719bSwdenk	R5-R10: parameter passing
4925c609719bSwdenk	R13:	small data area pointer
4926c609719bSwdenk	R30:	GOT pointer
4927c609719bSwdenk	R31:	frame pointer
4928c609719bSwdenk
4929e6bee808SJoakim Tjernlund	(U-Boot also uses R12 as internal GOT pointer. r12
4930e6bee808SJoakim Tjernlund	is a volatile register so r12 needs to be reset when
4931e6bee808SJoakim Tjernlund	going back and forth between asm and C)
4932c609719bSwdenk
4933e7670f6cSWolfgang Denk    ==> U-Boot will use R2 to hold a pointer to the global data
4934c609719bSwdenk
4935c609719bSwdenk    Note: on PPC, we could use a static initializer (since the
4936c609719bSwdenk    address of the global data structure is known at compile time),
4937c609719bSwdenk    but it turned out that reserving a register results in somewhat
4938c609719bSwdenk    smaller code - although the code savings are not that big (on
4939c609719bSwdenk    average for all boards 752 bytes for the whole U-Boot image,
4940c609719bSwdenk    624 text + 127 data).
4941c609719bSwdenk
4942c609719bSwdenkOn ARM, the following registers are used:
4943c609719bSwdenk
4944c609719bSwdenk	R0:	function argument word/integer result
4945c609719bSwdenk	R1-R3:	function argument word
494612eba1b4SJeroen Hofstee	R9:	platform specific
494712eba1b4SJeroen Hofstee	R10:	stack limit (used only if stack checking is enabled)
4948c609719bSwdenk	R11:	argument (frame) pointer
4949c609719bSwdenk	R12:	temporary workspace
4950c609719bSwdenk	R13:	stack pointer
4951c609719bSwdenk	R14:	link register
4952c609719bSwdenk	R15:	program counter
4953c609719bSwdenk
495412eba1b4SJeroen Hofstee    ==> U-Boot will use R9 to hold a pointer to the global data
495512eba1b4SJeroen Hofstee
495612eba1b4SJeroen Hofstee    Note: on ARM, only R_ARM_RELATIVE relocations are supported.
4957c609719bSwdenk
49580df01fd3SThomas ChouOn Nios II, the ABI is documented here:
49590df01fd3SThomas Chou	http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
49600df01fd3SThomas Chou
49610df01fd3SThomas Chou    ==> U-Boot will use gp to hold a pointer to the global data
49620df01fd3SThomas Chou
49630df01fd3SThomas Chou    Note: on Nios II, we give "-G0" option to gcc and don't use gp
49640df01fd3SThomas Chou    to access small data sections, so gp is free.
49650df01fd3SThomas Chou
4966afc1ce82SMacpaul LinOn NDS32, the following registers are used:
4967afc1ce82SMacpaul Lin
4968afc1ce82SMacpaul Lin	R0-R1:	argument/return
4969afc1ce82SMacpaul Lin	R2-R5:	argument
4970afc1ce82SMacpaul Lin	R15:	temporary register for assembler
4971afc1ce82SMacpaul Lin	R16:	trampoline register
4972afc1ce82SMacpaul Lin	R28:	frame pointer (FP)
4973afc1ce82SMacpaul Lin	R29:	global pointer (GP)
4974afc1ce82SMacpaul Lin	R30:	link register (LP)
4975afc1ce82SMacpaul Lin	R31:	stack pointer (SP)
4976afc1ce82SMacpaul Lin	PC:	program counter (PC)
4977afc1ce82SMacpaul Lin
4978afc1ce82SMacpaul Lin    ==> U-Boot will use R10 to hold a pointer to the global data
4979afc1ce82SMacpaul Lin
4980d87080b7SWolfgang DenkNOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4981d87080b7SWolfgang Denkor current versions of GCC may "optimize" the code too much.
4982c609719bSwdenk
4983c609719bSwdenkMemory Management:
4984c609719bSwdenk------------------
4985c609719bSwdenk
4986c609719bSwdenkU-Boot runs in system state and uses physical addresses, i.e. the
4987c609719bSwdenkMMU is not used either for address mapping nor for memory protection.
4988c609719bSwdenk
4989c609719bSwdenkThe available memory is mapped to fixed addresses using the memory
4990c609719bSwdenkcontroller. In this process, a contiguous block is formed for each
4991c609719bSwdenkmemory type (Flash, SDRAM, SRAM), even when it consists of several
4992c609719bSwdenkphysical memory banks.
4993c609719bSwdenk
4994c609719bSwdenkU-Boot is installed in the first 128 kB of the first Flash bank (on
4995c609719bSwdenkTQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4996c609719bSwdenkbooting and sizing and initializing DRAM, the code relocates itself
4997c609719bSwdenkto the upper end of DRAM. Immediately below the U-Boot code some
49986d0f6bcfSJean-Christophe PLAGNIOL-VILLARDmemory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4999c609719bSwdenkconfiguration setting]. Below that, a structure with global Board
5000c609719bSwdenkInfo data is placed, followed by the stack (growing downward).
5001c609719bSwdenk
5002c609719bSwdenkAdditionally, some exception handler code is copied to the low 8 kB
5003c609719bSwdenkof DRAM (0x00000000 ... 0x00001FFF).
5004c609719bSwdenk
5005c609719bSwdenkSo a typical memory configuration with 16 MB of DRAM could look like
5006c609719bSwdenkthis:
5007c609719bSwdenk
5008c609719bSwdenk	0x0000 0000	Exception Vector code
5009c609719bSwdenk	      :
5010c609719bSwdenk	0x0000 1FFF
5011c609719bSwdenk	0x0000 2000	Free for Application Use
5012c609719bSwdenk	      :
5013c609719bSwdenk	      :
5014c609719bSwdenk
5015c609719bSwdenk	      :
5016c609719bSwdenk	      :
5017c609719bSwdenk	0x00FB FF20	Monitor Stack (Growing downward)
5018c609719bSwdenk	0x00FB FFAC	Board Info Data and permanent copy of global data
5019c609719bSwdenk	0x00FC 0000	Malloc Arena
5020c609719bSwdenk	      :
5021c609719bSwdenk	0x00FD FFFF
5022c609719bSwdenk	0x00FE 0000	RAM Copy of Monitor Code
5023c609719bSwdenk	...		eventually: LCD or video framebuffer
5024c609719bSwdenk	...		eventually: pRAM (Protected RAM - unchanged by reset)
5025c609719bSwdenk	0x00FF FFFF	[End of RAM]
5026c609719bSwdenk
5027c609719bSwdenk
5028c609719bSwdenkSystem Initialization:
5029c609719bSwdenk----------------------
5030c609719bSwdenk
5031c609719bSwdenkIn the reset configuration, U-Boot starts at the reset entry point
503211ccc33fSMarcel Ziswiler(on most PowerPC systems at address 0x00000100). Because of the reset
5033c609719bSwdenkconfiguration for CS0# this is a mirror of the on board Flash memory.
50347152b1d0SwdenkTo be able to re-map memory U-Boot then jumps to its link address.
5035c609719bSwdenkTo be able to implement the initialization code in C, a (small!)
5036c609719bSwdenkinitial stack is set up in the internal Dual Ported RAM (in case CPUs
50372eb48ff7SHeiko Schocherwhich provide such a feature like), or in a locked part of the data
50382eb48ff7SHeiko Schochercache. After that, U-Boot initializes the CPU core, the caches and
50392eb48ff7SHeiko Schocherthe SIU.
5040c609719bSwdenk
5041c609719bSwdenkNext, all (potentially) available memory banks are mapped using a
5042c609719bSwdenkpreliminary mapping. For example, we put them on 512 MB boundaries
5043c609719bSwdenk(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5044c609719bSwdenkon 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5045c609719bSwdenkprogrammed for SDRAM access. Using the temporary configuration, a
5046c609719bSwdenksimple memory test is run that determines the size of the SDRAM
5047c609719bSwdenkbanks.
5048c609719bSwdenk
5049c609719bSwdenkWhen there is more than one SDRAM bank, and the banks are of
50507152b1d0Swdenkdifferent size, the largest is mapped first. For equal size, the first
5051c609719bSwdenkbank (CS2#) is mapped first. The first mapping is always for address
5052c609719bSwdenk0x00000000, with any additional banks following immediately to create
5053c609719bSwdenkcontiguous memory starting from 0.
5054c609719bSwdenk
5055c609719bSwdenkThen, the monitor installs itself at the upper end of the SDRAM area
5056c609719bSwdenkand allocates memory for use by malloc() and for the global Board
5057c609719bSwdenkInfo data; also, the exception vector code is copied to the low RAM
5058c609719bSwdenkpages, and the final stack is set up.
5059c609719bSwdenk
5060c609719bSwdenkOnly after this relocation will you have a "normal" C environment;
5061c609719bSwdenkuntil that you are restricted in several ways, mostly because you are
5062c609719bSwdenkrunning from ROM, and because the code will have to be relocated to a
5063c609719bSwdenknew address in RAM.
5064c609719bSwdenk
5065c609719bSwdenk
5066c609719bSwdenkU-Boot Porting Guide:
5067c609719bSwdenk----------------------
5068c609719bSwdenk
5069c609719bSwdenk[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
50706aff3115Swdenklist, October 2002]
5071c609719bSwdenk
5072c609719bSwdenk
5073c609719bSwdenkint main(int argc, char *argv[])
5074c609719bSwdenk{
5075c609719bSwdenk	sighandler_t no_more_time;
5076c609719bSwdenk
5077c609719bSwdenk	signal(SIGALRM, no_more_time);
5078c609719bSwdenk	alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5079c609719bSwdenk
5080c609719bSwdenk	if (available_money > available_manpower) {
50816c3fef28SJerry Van Baren		Pay consultant to port U-Boot;
5082c609719bSwdenk		return 0;
5083c609719bSwdenk	}
5084c609719bSwdenk
5085c609719bSwdenk	Download latest U-Boot source;
5086c609719bSwdenk
50870668236bSWolfgang Denk	Subscribe to u-boot mailing list;
50886aff3115Swdenk
50896c3fef28SJerry Van Baren	if (clueless)
5090c609719bSwdenk		email("Hi, I am new to U-Boot, how do I get started?");
5091c609719bSwdenk
5092c609719bSwdenk	while (learning) {
5093c609719bSwdenk		Read the README file in the top level directory;
50947cb22f97Swdenk		Read http://www.denx.de/twiki/bin/view/DULG/Manual;
50956c3fef28SJerry Van Baren		Read applicable doc/*.README;
5096c609719bSwdenk		Read the source, Luke;
50976c3fef28SJerry Van Baren		/* find . -name "*.[chS]" | xargs grep -i <keyword> */
5098c609719bSwdenk	}
5099c609719bSwdenk
51006c3fef28SJerry Van Baren	if (available_money > toLocalCurrency ($2500))
51016c3fef28SJerry Van Baren		Buy a BDI3000;
51026c3fef28SJerry Van Baren	else
5103c609719bSwdenk		Add a lot of aggravation and time;
5104c609719bSwdenk
51056c3fef28SJerry Van Baren	if (a similar board exists) {	/* hopefully... */
51066c3fef28SJerry Van Baren		cp -a board/<similar> board/<myboard>
51076c3fef28SJerry Van Baren		cp include/configs/<similar>.h include/configs/<myboard>.h
51086c3fef28SJerry Van Baren	} else {
5109c609719bSwdenk		Create your own board support subdirectory;
51106c3fef28SJerry Van Baren		Create your own board include/configs/<myboard>.h file;
51116c3fef28SJerry Van Baren	}
51126c3fef28SJerry Van Baren	Edit new board/<myboard> files
51136c3fef28SJerry Van Baren	Edit new include/configs/<myboard>.h
5114c609719bSwdenk
51156c3fef28SJerry Van Baren	while (!accepted) {
5116c609719bSwdenk		while (!running) {
5117c609719bSwdenk			do {
5118c609719bSwdenk				Add / modify source code;
5119c609719bSwdenk			} until (compiles);
5120c609719bSwdenk			Debug;
5121c609719bSwdenk			if (clueless)
5122c609719bSwdenk				email("Hi, I am having problems...");
5123c609719bSwdenk		}
51246c3fef28SJerry Van Baren		Send patch file to the U-Boot email list;
51256c3fef28SJerry Van Baren		if (reasonable critiques)
51266c3fef28SJerry Van Baren			Incorporate improvements from email list code review;
51276c3fef28SJerry Van Baren		else
51286c3fef28SJerry Van Baren			Defend code as written;
51296c3fef28SJerry Van Baren	}
5130c609719bSwdenk
5131c609719bSwdenk	return 0;
5132c609719bSwdenk}
5133c609719bSwdenk
5134c609719bSwdenkvoid no_more_time (int sig)
5135c609719bSwdenk{
5136c609719bSwdenk      hire_a_guru();
5137c609719bSwdenk}
5138c609719bSwdenk
5139c609719bSwdenk
5140c609719bSwdenkCoding Standards:
5141c609719bSwdenk-----------------
5142c609719bSwdenk
5143c609719bSwdenkAll contributions to U-Boot should conform to the Linux kernel
51442c051651SDetlev Zundelcoding style; see the file "Documentation/CodingStyle" and the script
51457ca9296eSWolfgang Denk"scripts/Lindent" in your Linux kernel source directory.
5146c609719bSwdenk
51472c051651SDetlev ZundelSource files originating from a different project (for example the
51482c051651SDetlev ZundelMTD subsystem) are generally exempt from these guidelines and are not
5149b445bbb4SJeremiah Mahlerreformatted to ease subsequent migration to newer versions of those
51502c051651SDetlev Zundelsources.
51512c051651SDetlev Zundel
51522c051651SDetlev ZundelPlease note that U-Boot is implemented in C (and to some small parts in
51532c051651SDetlev ZundelAssembler); no C++ is used, so please do not use C++ style comments (//)
51542c051651SDetlev Zundelin your code.
5155c609719bSwdenk
5156c178d3daSwdenkPlease also stick to the following formatting rules:
5157180d3f74Swdenk- remove any trailing white space
51587ca9296eSWolfgang Denk- use TAB characters for indentation and vertical alignment, not spaces
5159180d3f74Swdenk- make sure NOT to use DOS '\r\n' line feeds
51607ca9296eSWolfgang Denk- do not add more than 2 consecutive empty lines to source files
5161180d3f74Swdenk- do not add trailing empty lines to source files
5162180d3f74Swdenk
5163c609719bSwdenkSubmissions which do not conform to the standards may be returned
5164c609719bSwdenkwith a request to reformat the changes.
5165c609719bSwdenk
5166c609719bSwdenk
5167c609719bSwdenkSubmitting Patches:
5168c609719bSwdenk-------------------
5169c609719bSwdenk
5170c609719bSwdenkSince the number of patches for U-Boot is growing, we need to
5171c609719bSwdenkestablish some rules. Submissions which do not conform to these rules
5172c609719bSwdenkmay be rejected, even when they contain important and valuable stuff.
5173c609719bSwdenk
51740d28f34bSMagnus LiljaPlease see http://www.denx.de/wiki/U-Boot/Patches for details.
5175218ca724SWolfgang Denk
51760668236bSWolfgang DenkPatches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
51770668236bSWolfgang Denksee http://lists.denx.de/mailman/listinfo/u-boot
51780668236bSWolfgang Denk
5179c609719bSwdenkWhen you send a patch, please include the following information with
5180c609719bSwdenkit:
5181c609719bSwdenk
5182c609719bSwdenk* For bug fixes: a description of the bug and how your patch fixes
5183c609719bSwdenk  this bug. Please try to include a way of demonstrating that the
5184c609719bSwdenk  patch actually fixes something.
5185c609719bSwdenk
5186c609719bSwdenk* For new features: a description of the feature and your
5187c609719bSwdenk  implementation.
5188c609719bSwdenk
5189c609719bSwdenk* A CHANGELOG entry as plaintext (separate from the patch)
5190c609719bSwdenk
51917207b366SRobert P. J. Day* For major contributions, add a MAINTAINERS file with your
51927207b366SRobert P. J. Day  information and associated file and directory references.
5193c609719bSwdenk
519427af930eSAlbert ARIBAUD* When you add support for a new board, don't forget to add a
519527af930eSAlbert ARIBAUD  maintainer e-mail address to the boards.cfg file, too.
5196c609719bSwdenk
5197c609719bSwdenk* If your patch adds new configuration options, don't forget to
5198c609719bSwdenk  document these in the README file.
5199c609719bSwdenk
5200218ca724SWolfgang Denk* The patch itself. If you are using git (which is *strongly*
5201218ca724SWolfgang Denk  recommended) you can easily generate the patch using the
52027ca9296eSWolfgang Denk  "git format-patch". If you then use "git send-email" to send it to
5203218ca724SWolfgang Denk  the U-Boot mailing list, you will avoid most of the common problems
5204218ca724SWolfgang Denk  with some other mail clients.
5205c609719bSwdenk
5206218ca724SWolfgang Denk  If you cannot use git, use "diff -purN OLD NEW". If your version of
5207218ca724SWolfgang Denk  diff does not support these options, then get the latest version of
5208218ca724SWolfgang Denk  GNU diff.
52096dff5529Swdenk
5210218ca724SWolfgang Denk  The current directory when running this command shall be the parent
5211218ca724SWolfgang Denk  directory of the U-Boot source tree (i. e. please make sure that
5212218ca724SWolfgang Denk  your patch includes sufficient directory information for the
5213218ca724SWolfgang Denk  affected files).
5214218ca724SWolfgang Denk
5215218ca724SWolfgang Denk  We prefer patches as plain text. MIME attachments are discouraged,
5216218ca724SWolfgang Denk  and compressed attachments must not be used.
5217c609719bSwdenk
521852f52c14Swdenk* If one logical set of modifications affects or creates several
521952f52c14Swdenk  files, all these changes shall be submitted in a SINGLE patch file.
522052f52c14Swdenk
522152f52c14Swdenk* Changesets that contain different, unrelated modifications shall be
522252f52c14Swdenk  submitted as SEPARATE patches, one patch per changeset.
522352f52c14Swdenk
522452f52c14Swdenk
5225c609719bSwdenkNotes:
5226c609719bSwdenk
52276de80f21SSimon Glass* Before sending the patch, run the buildman script on your patched
5228c609719bSwdenk  source tree and make sure that no errors or warnings are reported
5229c609719bSwdenk  for any of the boards.
5230c609719bSwdenk
5231c609719bSwdenk* Keep your modifications to the necessary minimum: A patch
5232c609719bSwdenk  containing several unrelated changes or arbitrary reformats will be
5233c609719bSwdenk  returned with a request to re-formatting / split it.
5234c609719bSwdenk
5235c609719bSwdenk* If you modify existing code, make sure that your new code does not
5236c609719bSwdenk  add to the memory footprint of the code ;-) Small is beautiful!
5237c609719bSwdenk  When adding new features, these should compile conditionally only
5238c609719bSwdenk  (using #ifdef), and the resulting code with the new feature
5239c609719bSwdenk  disabled must not need more memory than the old code without your
5240c609719bSwdenk  modification.
524190dc6704Swdenk
52420668236bSWolfgang Denk* Remember that there is a size limit of 100 kB per message on the
52430668236bSWolfgang Denk  u-boot mailing list. Bigger patches will be moderated. If they are
52440668236bSWolfgang Denk  reasonable and not too big, they will be acknowledged. But patches
52450668236bSWolfgang Denk  bigger than the size limit should be avoided.
5246