xref: /openbmc/u-boot/README (revision 8fdf1e0f6d645f79a9b0677e062bf48d786c5b9e)
1c609719bSwdenk#
2b75190deSWolfgang Denk# (C) Copyright 2000 - 2012
3c609719bSwdenk# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4c609719bSwdenk#
5c609719bSwdenk# See file CREDITS for list of people who contributed to this
6c609719bSwdenk# project.
7c609719bSwdenk#
8c609719bSwdenk# This program is free software; you can redistribute it and/or
9c609719bSwdenk# modify it under the terms of the GNU General Public License as
10c609719bSwdenk# published by the Free Software Foundation; either version 2 of
11c609719bSwdenk# the License, or (at your option) any later version.
12c609719bSwdenk#
13c609719bSwdenk# This program is distributed in the hope that it will be useful,
14c609719bSwdenk# but WITHOUT ANY WARRANTY; without even the implied warranty of
15c609719bSwdenk# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
16c609719bSwdenk# GNU General Public License for more details.
17c609719bSwdenk#
18c609719bSwdenk# You should have received a copy of the GNU General Public License
19c609719bSwdenk# along with this program; if not, write to the Free Software
20c609719bSwdenk# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21c609719bSwdenk# MA 02111-1307 USA
22c609719bSwdenk#
23c609719bSwdenk
24c609719bSwdenkSummary:
25c609719bSwdenk========
26c609719bSwdenk
2724ee89b9SwdenkThis directory contains the source code for U-Boot, a boot loader for
28e86e5a07SwdenkEmbedded boards based on PowerPC, ARM, MIPS and several other
29e86e5a07Swdenkprocessors, which can be installed in a boot ROM and used to
30e86e5a07Swdenkinitialize and test the hardware or to download and run application
31e86e5a07Swdenkcode.
32c609719bSwdenk
33c609719bSwdenkThe development of U-Boot is closely related to Linux: some parts of
3424ee89b9Swdenkthe source code originate in the Linux source tree, we have some
3524ee89b9Swdenkheader files in common, and special provision has been made to
36c609719bSwdenksupport booting of Linux images.
37c609719bSwdenk
38c609719bSwdenkSome attention has been paid to make this software easily
39c609719bSwdenkconfigurable and extendable. For instance, all monitor commands are
40c609719bSwdenkimplemented with the same call interface, so that it's very easy to
41c609719bSwdenkadd new commands. Also, instead of permanently adding rarely used
42c609719bSwdenkcode (for instance hardware test utilities) to the monitor, you can
43c609719bSwdenkload and run it dynamically.
44c609719bSwdenk
45c609719bSwdenk
46c609719bSwdenkStatus:
47c609719bSwdenk=======
48c609719bSwdenk
49c609719bSwdenkIn general, all boards for which a configuration option exists in the
50c609719bSwdenkMakefile have been tested to some extent and can be considered
51c609719bSwdenk"working". In fact, many of them are used in production systems.
52c609719bSwdenk
53c609719bSwdenkIn case of problems see the CHANGELOG and CREDITS files to find out
54218ca724SWolfgang Denkwho contributed the specific port. The MAINTAINERS file lists board
55218ca724SWolfgang Denkmaintainers.
56c609719bSwdenk
57adb9d851SRobert P. J. DayNote: There is no CHANGELOG file in the actual U-Boot source tree;
58adb9d851SRobert P. J. Dayit can be created dynamically from the Git log using:
59adb9d851SRobert P. J. Day
60adb9d851SRobert P. J. Day	make CHANGELOG
61adb9d851SRobert P. J. Day
62c609719bSwdenk
63c609719bSwdenkWhere to get help:
64c609719bSwdenk==================
65c609719bSwdenk
66c609719bSwdenkIn case you have questions about, problems with or contributions for
67c609719bSwdenkU-Boot you should send a message to the U-Boot mailing list at
680c32565fSPeter Tyser<u-boot@lists.denx.de>. There is also an archive of previous traffic
690c32565fSPeter Tyseron the mailing list - please search the archive before asking FAQ's.
700c32565fSPeter TyserPlease see http://lists.denx.de/pipermail/u-boot and
710c32565fSPeter Tyserhttp://dir.gmane.org/gmane.comp.boot-loaders.u-boot
72c609719bSwdenk
73c609719bSwdenk
74218ca724SWolfgang DenkWhere to get source code:
75218ca724SWolfgang Denk=========================
76218ca724SWolfgang Denk
77218ca724SWolfgang DenkThe U-Boot source code is maintained in the git repository at
78218ca724SWolfgang Denkgit://www.denx.de/git/u-boot.git ; you can browse it online at
79218ca724SWolfgang Denkhttp://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
80218ca724SWolfgang Denk
81218ca724SWolfgang DenkThe "snapshot" links on this page allow you to download tarballs of
8211ccc33fSMarcel Ziswilerany version you might be interested in. Official releases are also
83218ca724SWolfgang Denkavailable for FTP download from the ftp://ftp.denx.de/pub/u-boot/
84218ca724SWolfgang Denkdirectory.
85218ca724SWolfgang Denk
86d4ee711dSAnatolij GustschinPre-built (and tested) images are available from
87218ca724SWolfgang Denkftp://ftp.denx.de/pub/u-boot/images/
88218ca724SWolfgang Denk
89218ca724SWolfgang Denk
90c609719bSwdenkWhere we come from:
91c609719bSwdenk===================
92c609719bSwdenk
93c609719bSwdenk- start from 8xxrom sources
9424ee89b9Swdenk- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
95c609719bSwdenk- clean up code
96c609719bSwdenk- make it easier to add custom boards
97c609719bSwdenk- make it possible to add other [PowerPC] CPUs
98c609719bSwdenk- extend functions, especially:
99c609719bSwdenk  * Provide extended interface to Linux boot loader
100c609719bSwdenk  * S-Record download
101c609719bSwdenk  * network boot
10211ccc33fSMarcel Ziswiler  * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
10324ee89b9Swdenk- create ARMBoot project (http://sourceforge.net/projects/armboot)
104c609719bSwdenk- add other CPU families (starting with ARM)
10524ee89b9Swdenk- create U-Boot project (http://sourceforge.net/projects/u-boot)
1060d28f34bSMagnus Lilja- current project page: see http://www.denx.de/wiki/U-Boot
10724ee89b9Swdenk
10824ee89b9Swdenk
10924ee89b9SwdenkNames and Spelling:
11024ee89b9Swdenk===================
11124ee89b9Swdenk
11224ee89b9SwdenkThe "official" name of this project is "Das U-Boot". The spelling
11324ee89b9Swdenk"U-Boot" shall be used in all written text (documentation, comments
11424ee89b9Swdenkin source files etc.). Example:
11524ee89b9Swdenk
11624ee89b9Swdenk	This is the README file for the U-Boot project.
11724ee89b9Swdenk
11824ee89b9SwdenkFile names etc. shall be based on the string "u-boot". Examples:
11924ee89b9Swdenk
12024ee89b9Swdenk	include/asm-ppc/u-boot.h
12124ee89b9Swdenk
12224ee89b9Swdenk	#include <asm/u-boot.h>
12324ee89b9Swdenk
12424ee89b9SwdenkVariable names, preprocessor constants etc. shall be either based on
12524ee89b9Swdenkthe string "u_boot" or on "U_BOOT". Example:
12624ee89b9Swdenk
12724ee89b9Swdenk	U_BOOT_VERSION		u_boot_logo
12824ee89b9Swdenk	IH_OS_U_BOOT		u_boot_hush_start
129c609719bSwdenk
130c609719bSwdenk
13193f19cc0SwdenkVersioning:
13293f19cc0Swdenk===========
13393f19cc0Swdenk
134360d883aSThomas WeberStarting with the release in October 2008, the names of the releases
135360d883aSThomas Weberwere changed from numerical release numbers without deeper meaning
136360d883aSThomas Weberinto a time stamp based numbering. Regular releases are identified by
137360d883aSThomas Webernames consisting of the calendar year and month of the release date.
138360d883aSThomas WeberAdditional fields (if present) indicate release candidates or bug fix
139360d883aSThomas Weberreleases in "stable" maintenance trees.
14093f19cc0Swdenk
141360d883aSThomas WeberExamples:
142360d883aSThomas Weber	U-Boot v2009.11	    - Release November 2009
143360d883aSThomas Weber	U-Boot v2009.11.1   - Release 1 in version November 2009 stable tree
144360d883aSThomas Weber	U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
14593f19cc0Swdenk
14693f19cc0Swdenk
147c609719bSwdenkDirectory Hierarchy:
148c609719bSwdenk====================
149c609719bSwdenk
1508d321b81SPeter Tyser/arch			Architecture specific files
1518d321b81SPeter Tyser  /arm			Files generic to ARM architecture
1528d321b81SPeter Tyser    /cpu		CPU specific files
1538d321b81SPeter Tyser      /arm720t		Files specific to ARM 720 CPUs
1548d321b81SPeter Tyser      /arm920t		Files specific to ARM 920 CPUs
1556eb0921aSAndreas Bießmann	/at91		Files specific to Atmel AT91RM9200 CPU
1568d321b81SPeter Tyser	/imx		Files specific to Freescale MC9328 i.MX CPUs
1578d321b81SPeter Tyser	/s3c24x0	Files specific to Samsung S3C24X0 CPUs
1588d321b81SPeter Tyser      /arm925t		Files specific to ARM 925 CPUs
1598d321b81SPeter Tyser      /arm926ejs	Files specific to ARM 926 CPUs
1608d321b81SPeter Tyser      /arm1136		Files specific to ARM 1136 CPUs
1618d321b81SPeter Tyser      /ixp		Files specific to Intel XScale IXP CPUs
1628d321b81SPeter Tyser      /pxa		Files specific to Intel XScale PXA CPUs
1638d321b81SPeter Tyser      /s3c44b0		Files specific to Samsung S3C44B0 CPUs
1648d321b81SPeter Tyser      /sa1100		Files specific to Intel StrongARM SA1100 CPUs
1658d321b81SPeter Tyser    /lib		Architecture specific library files
1668d321b81SPeter Tyser  /avr32		Files generic to AVR32 architecture
1678d321b81SPeter Tyser    /cpu		CPU specific files
1688d321b81SPeter Tyser    /lib		Architecture specific library files
1698d321b81SPeter Tyser  /blackfin		Files generic to Analog Devices Blackfin architecture
1708d321b81SPeter Tyser    /cpu		CPU specific files
1718d321b81SPeter Tyser    /lib		Architecture specific library files
172fea25720SGraeme Russ  /x86			Files generic to x86 architecture
1738d321b81SPeter Tyser    /cpu		CPU specific files
1748d321b81SPeter Tyser    /lib		Architecture specific library files
1758d321b81SPeter Tyser  /m68k			Files generic to m68k architecture
1768d321b81SPeter Tyser    /cpu		CPU specific files
1778d321b81SPeter Tyser      /mcf52x2		Files specific to Freescale ColdFire MCF52x2 CPUs
1788d321b81SPeter Tyser      /mcf5227x		Files specific to Freescale ColdFire MCF5227x CPUs
1798d321b81SPeter Tyser      /mcf532x		Files specific to Freescale ColdFire MCF5329 CPUs
1808d321b81SPeter Tyser      /mcf5445x		Files specific to Freescale ColdFire MCF5445x CPUs
1818d321b81SPeter Tyser      /mcf547x_8x	Files specific to Freescale ColdFire MCF547x_8x CPUs
1828d321b81SPeter Tyser    /lib		Architecture specific library files
1838d321b81SPeter Tyser  /microblaze		Files generic to microblaze architecture
1848d321b81SPeter Tyser    /cpu		CPU specific files
1858d321b81SPeter Tyser    /lib		Architecture specific library files
1868d321b81SPeter Tyser  /mips			Files generic to MIPS architecture
1878d321b81SPeter Tyser    /cpu		CPU specific files
18892bbd64eSDaniel Schwierzeck      /mips32		Files specific to MIPS32 CPUs
18980421fccSXiangfu Liu      /xburst		Files specific to Ingenic XBurst CPUs
1908d321b81SPeter Tyser    /lib		Architecture specific library files
191afc1ce82SMacpaul Lin  /nds32		Files generic to NDS32 architecture
192afc1ce82SMacpaul Lin    /cpu		CPU specific files
193afc1ce82SMacpaul Lin      /n1213		Files specific to Andes Technology N1213 CPUs
194afc1ce82SMacpaul Lin    /lib		Architecture specific library files
1958d321b81SPeter Tyser  /nios2		Files generic to Altera NIOS2 architecture
1968d321b81SPeter Tyser    /cpu		CPU specific files
1978d321b81SPeter Tyser    /lib		Architecture specific library files
198a47a12beSStefan Roese  /powerpc		Files generic to PowerPC architecture
1998d321b81SPeter Tyser    /cpu		CPU specific files
2008d321b81SPeter Tyser      /74xx_7xx		Files specific to Freescale MPC74xx and 7xx CPUs
2018d321b81SPeter Tyser      /mpc5xx		Files specific to Freescale MPC5xx CPUs
2028d321b81SPeter Tyser      /mpc5xxx		Files specific to Freescale MPC5xxx CPUs
2038d321b81SPeter Tyser      /mpc8xx		Files specific to Freescale MPC8xx CPUs
2048d321b81SPeter Tyser      /mpc8220		Files specific to Freescale MPC8220 CPUs
2058d321b81SPeter Tyser      /mpc824x		Files specific to Freescale MPC824x CPUs
2068d321b81SPeter Tyser      /mpc8260		Files specific to Freescale MPC8260 CPUs
2078d321b81SPeter Tyser      /mpc85xx		Files specific to Freescale MPC85xx CPUs
2088d321b81SPeter Tyser      /ppc4xx		Files specific to AMCC PowerPC 4xx CPUs
2098d321b81SPeter Tyser    /lib		Architecture specific library files
2108d321b81SPeter Tyser  /sh			Files generic to SH architecture
2118d321b81SPeter Tyser    /cpu		CPU specific files
2128d321b81SPeter Tyser      /sh2		Files specific to sh2 CPUs
2138d321b81SPeter Tyser      /sh3		Files specific to sh3 CPUs
2148d321b81SPeter Tyser      /sh4		Files specific to sh4 CPUs
2158d321b81SPeter Tyser    /lib		Architecture specific library files
2168d321b81SPeter Tyser  /sparc		Files generic to SPARC architecture
2178d321b81SPeter Tyser    /cpu		CPU specific files
2188d321b81SPeter Tyser      /leon2		Files specific to Gaisler LEON2 SPARC CPU
2198d321b81SPeter Tyser      /leon3		Files specific to Gaisler LEON3 SPARC CPU
2208d321b81SPeter Tyser    /lib		Architecture specific library files
2218d321b81SPeter Tyser/api			Machine/arch independent API for external apps
2228d321b81SPeter Tyser/board			Board dependent files
2238d321b81SPeter Tyser/common			Misc architecture independent functions
2248d321b81SPeter Tyser/disk			Code for disk drive partition handling
2258d321b81SPeter Tyser/doc			Documentation (don't expect too much)
2268d321b81SPeter Tyser/drivers		Commonly used device drivers
2278d321b81SPeter Tyser/examples		Example code for standalone applications, etc.
2288d321b81SPeter Tyser/fs			Filesystem code (cramfs, ext2, jffs2, etc.)
2298d321b81SPeter Tyser/include		Header Files
2308d321b81SPeter Tyser/lib			Files generic to all architectures
2318d321b81SPeter Tyser  /libfdt		Library files to support flattened device trees
2328d321b81SPeter Tyser  /lzma			Library files to support LZMA decompression
2338d321b81SPeter Tyser  /lzo			Library files to support LZO decompression
2348d321b81SPeter Tyser/net			Networking code
2358d321b81SPeter Tyser/post			Power On Self Test
2368d321b81SPeter Tyser/rtc			Real Time Clock drivers
2378d321b81SPeter Tyser/tools			Tools to build S-Record or U-Boot images, etc.
238c609719bSwdenk
239c609719bSwdenkSoftware Configuration:
240c609719bSwdenk=======================
241c609719bSwdenk
242c609719bSwdenkConfiguration is usually done using C preprocessor defines; the
243c609719bSwdenkrationale behind that is to avoid dead code whenever possible.
244c609719bSwdenk
245c609719bSwdenkThere are two classes of configuration variables:
246c609719bSwdenk
247c609719bSwdenk* Configuration _OPTIONS_:
248c609719bSwdenk  These are selectable by the user and have names beginning with
249c609719bSwdenk  "CONFIG_".
250c609719bSwdenk
251c609719bSwdenk* Configuration _SETTINGS_:
252c609719bSwdenk  These depend on the hardware etc. and should not be meddled with if
253c609719bSwdenk  you don't know what you're doing; they have names beginning with
2546d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  "CONFIG_SYS_".
255c609719bSwdenk
256c609719bSwdenkLater we will add a configuration tool - probably similar to or even
257c609719bSwdenkidentical to what's used for the Linux kernel. Right now, we have to
258c609719bSwdenkdo the configuration by hand, which means creating some symbolic
259c609719bSwdenklinks and editing some configuration files. We use the TQM8xxL boards
260c609719bSwdenkas an example here.
261c609719bSwdenk
262c609719bSwdenk
263c609719bSwdenkSelection of Processor Architecture and Board Type:
264c609719bSwdenk---------------------------------------------------
265c609719bSwdenk
266c609719bSwdenkFor all supported boards there are ready-to-use default
267c609719bSwdenkconfigurations available; just type "make <board_name>_config".
268c609719bSwdenk
269c609719bSwdenkExample: For a TQM823L module type:
270c609719bSwdenk
271c609719bSwdenk	cd u-boot
272c609719bSwdenk	make TQM823L_config
273c609719bSwdenk
27411ccc33fSMarcel ZiswilerFor the Cogent platform, you need to specify the CPU type as well;
275c609719bSwdenke.g. "make cogent_mpc8xx_config". And also configure the cogent
276c609719bSwdenkdirectory according to the instructions in cogent/README.
277c609719bSwdenk
278c609719bSwdenk
279c609719bSwdenkConfiguration Options:
280c609719bSwdenk----------------------
281c609719bSwdenk
282c609719bSwdenkConfiguration depends on the combination of board and CPU type; all
283c609719bSwdenksuch information is kept in a configuration file
284c609719bSwdenk"include/configs/<board_name>.h".
285c609719bSwdenk
286c609719bSwdenkExample: For a TQM823L module, all configuration settings are in
287c609719bSwdenk"include/configs/TQM823L.h".
288c609719bSwdenk
289c609719bSwdenk
2907f6c2cbcSwdenkMany of the options are named exactly as the corresponding Linux
2917f6c2cbcSwdenkkernel configuration options. The intention is to make it easier to
2927f6c2cbcSwdenkbuild a config tool - later.
2937f6c2cbcSwdenk
2947f6c2cbcSwdenk
295c609719bSwdenkThe following options need to be configured:
296c609719bSwdenk
2972628114eSKim Phillips- CPU Type:	Define exactly one, e.g. CONFIG_MPC85XX.
298c609719bSwdenk
2992628114eSKim Phillips- Board Type:	Define exactly one, e.g. CONFIG_MPC8540ADS.
3006ccec449SWolfgang Denk
3016ccec449SWolfgang Denk- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
30209ea0de0SHaavard Skinnemoen		Define exactly one, e.g. CONFIG_ATSTK1002
303c609719bSwdenk
304c609719bSwdenk- CPU Module Type: (if CONFIG_COGENT is defined)
305c609719bSwdenk		Define exactly one of
306c609719bSwdenk		CONFIG_CMA286_60_OLD
307c609719bSwdenk--- FIXME --- not tested yet:
308c609719bSwdenk		CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
309c609719bSwdenk		CONFIG_CMA287_23, CONFIG_CMA287_50
310c609719bSwdenk
311c609719bSwdenk- Motherboard Type: (if CONFIG_COGENT is defined)
312c609719bSwdenk		Define exactly one of
313c609719bSwdenk		CONFIG_CMA101, CONFIG_CMA102
314c609719bSwdenk
315c609719bSwdenk- Motherboard I/O Modules: (if CONFIG_COGENT is defined)
316c609719bSwdenk		Define one or more of
317c609719bSwdenk		CONFIG_CMA302
318c609719bSwdenk
319c609719bSwdenk- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
320c609719bSwdenk		Define one or more of
321c609719bSwdenk		CONFIG_LCD_HEARTBEAT	- update a character position on
32211ccc33fSMarcel Ziswiler					  the LCD display every second with
323c609719bSwdenk					  a "rotator" |\-/|\-/
324c609719bSwdenk
3252535d602Swdenk- Board flavour: (if CONFIG_MPC8260ADS is defined)
3262535d602Swdenk		CONFIG_ADSTYPE
3272535d602Swdenk		Possible values are:
3286d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_8260ADS	- original MPC8260ADS
3296d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_8266ADS	- MPC8266ADS
3306d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_PQ2FADS	- PQ2FADS-ZU or PQ2FADS-VR
3316d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_8272ADS	- MPC8272ADS
3322535d602Swdenk
333cf946c6dSLei Wen- Marvell Family Member
334cf946c6dSLei Wen		CONFIG_SYS_MVFS		- define it if you want to enable
335cf946c6dSLei Wen					  multiple fs option at one time
336cf946c6dSLei Wen					  for marvell soc family
337cf946c6dSLei Wen
338c609719bSwdenk- MPC824X Family Member (if CONFIG_MPC824X is defined)
339c609719bSwdenk		Define exactly one of
340c609719bSwdenk		CONFIG_MPC8240, CONFIG_MPC8245
341c609719bSwdenk
34211ccc33fSMarcel Ziswiler- 8xx CPU Options: (if using an MPC8xx CPU)
34366ca92a5Swdenk		CONFIG_8xx_GCLK_FREQ	- deprecated: CPU clock if
34466ca92a5Swdenk					  get_gclk_freq() cannot work
3455da627a4Swdenk					  e.g. if there is no 32KHz
3465da627a4Swdenk					  reference PIT/RTC clock
34766ca92a5Swdenk		CONFIG_8xx_OSCLK	- PLL input clock (either EXTCLK
34866ca92a5Swdenk					  or XTAL/EXTAL)
349c609719bSwdenk
35066ca92a5Swdenk- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
3516d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_8xx_CPUCLK_MIN
3526d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_8xx_CPUCLK_MAX
35366ca92a5Swdenk		CONFIG_8xx_CPUCLK_DEFAULT
35475d1ea7fSwdenk			See doc/README.MPC866
35575d1ea7fSwdenk
3566d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_MEASURE_CPUCLK
35775d1ea7fSwdenk
35875d1ea7fSwdenk		Define this to measure the actual CPU clock instead
35975d1ea7fSwdenk		of relying on the correctness of the configured
36075d1ea7fSwdenk		values. Mostly useful for board bringup to make sure
36175d1ea7fSwdenk		the PLL is locked at the intended frequency. Note
36275d1ea7fSwdenk		that this requires a (stable) reference clock (32 kHz
3636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		RTC clock or CONFIG_SYS_8XX_XIN)
36475d1ea7fSwdenk
365506f3918SHeiko Schocher		CONFIG_SYS_DELAYED_ICACHE
366506f3918SHeiko Schocher
367506f3918SHeiko Schocher		Define this option if you want to enable the
368506f3918SHeiko Schocher		ICache only when Code runs from RAM.
369506f3918SHeiko Schocher
37066412c63SKumar Gala- 85xx CPU Options:
371ffd06e02SYork Sun		CONFIG_SYS_PPC64
372ffd06e02SYork Sun
373ffd06e02SYork Sun		Specifies that the core is a 64-bit PowerPC implementation (implements
374ffd06e02SYork Sun		the "64" category of the Power ISA). This is necessary for ePAPR
375ffd06e02SYork Sun		compliance, among other possible reasons.
376ffd06e02SYork Sun
37766412c63SKumar Gala		CONFIG_SYS_FSL_TBCLK_DIV
37866412c63SKumar Gala
37966412c63SKumar Gala		Defines the core time base clock divider ratio compared to the
38066412c63SKumar Gala		system clock.  On most PQ3 devices this is 8, on newer QorIQ
38166412c63SKumar Gala		devices it can be 16 or 32.  The ratio varies from SoC to Soc.
38266412c63SKumar Gala
3838f29084aSKumar Gala		CONFIG_SYS_FSL_PCIE_COMPAT
3848f29084aSKumar Gala
3858f29084aSKumar Gala		Defines the string to utilize when trying to match PCIe device
3868f29084aSKumar Gala		tree nodes for the given platform.
3878f29084aSKumar Gala
388afa6b551SPrabhakar Kushwaha		CONFIG_SYS_PPC_E500_DEBUG_TLB
389afa6b551SPrabhakar Kushwaha
390afa6b551SPrabhakar Kushwaha		Enables a temporary TLB entry to be used during boot to work
391afa6b551SPrabhakar Kushwaha		around limitations in e500v1 and e500v2 external debugger
392afa6b551SPrabhakar Kushwaha		support. This reduces the portions of the boot code where
393afa6b551SPrabhakar Kushwaha		breakpoints and single stepping do not work.  The value of this
394afa6b551SPrabhakar Kushwaha		symbol should be set to the TLB1 entry to be used for this
395afa6b551SPrabhakar Kushwaha		purpose.
396afa6b551SPrabhakar Kushwaha
39733eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510
39833eee330SScott Wood
39933eee330SScott Wood		Enables a workaround for erratum A004510.  If set,
40033eee330SScott Wood		then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
40133eee330SScott Wood		CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
40233eee330SScott Wood
40333eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
40433eee330SScott Wood		CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
40533eee330SScott Wood
40633eee330SScott Wood		Defines one or two SoC revisions (low 8 bits of SVR)
40733eee330SScott Wood		for which the A004510 workaround should be applied.
40833eee330SScott Wood
40933eee330SScott Wood		The rest of SVR is either not relevant to the decision
41033eee330SScott Wood		of whether the erratum is present (e.g. p2040 versus
41133eee330SScott Wood		p2041) or is implied by the build target, which controls
41233eee330SScott Wood		whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
41333eee330SScott Wood
41433eee330SScott Wood		See Freescale App Note 4493 for more information about
41533eee330SScott Wood		this erratum.
41633eee330SScott Wood
41733eee330SScott Wood		CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
41833eee330SScott Wood
41933eee330SScott Wood		This is the value to write into CCSR offset 0x18600
42033eee330SScott Wood		according to the A004510 workaround.
42133eee330SScott Wood
4226cb461b4SDaniel Schwierzeck- Generic CPU options:
4236cb461b4SDaniel Schwierzeck		CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
4246cb461b4SDaniel Schwierzeck
4256cb461b4SDaniel Schwierzeck		Defines the endianess of the CPU. Implementation of those
4266cb461b4SDaniel Schwierzeck		values is arch specific.
4276cb461b4SDaniel Schwierzeck
4280b953ffcSMarkus Klotzbuecher- Intel Monahans options:
4296d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
4300b953ffcSMarkus Klotzbuecher
4310b953ffcSMarkus Klotzbuecher		Defines the Monahans run mode to oscillator
4320b953ffcSMarkus Klotzbuecher		ratio. Valid values are 8, 16, 24, 31. The core
4330b953ffcSMarkus Klotzbuecher		frequency is this value multiplied by 13 MHz.
4340b953ffcSMarkus Klotzbuecher
4356d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
4360b953ffcSMarkus Klotzbuecher
4370b953ffcSMarkus Klotzbuecher		Defines the Monahans turbo mode to oscillator
4380b953ffcSMarkus Klotzbuecher		ratio. Valid values are 1 (default if undefined) and
4390b953ffcSMarkus Klotzbuecher		2. The core frequency as calculated above is multiplied
4400b953ffcSMarkus Klotzbuecher		by this value.
4410b953ffcSMarkus Klotzbuecher
44292bbd64eSDaniel Schwierzeck- MIPS CPU options:
44392bbd64eSDaniel Schwierzeck		CONFIG_SYS_INIT_SP_OFFSET
44492bbd64eSDaniel Schwierzeck
44592bbd64eSDaniel Schwierzeck		Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
44692bbd64eSDaniel Schwierzeck		pointer. This is needed for the temporary stack before
44792bbd64eSDaniel Schwierzeck		relocation.
44892bbd64eSDaniel Schwierzeck
44992bbd64eSDaniel Schwierzeck		CONFIG_SYS_MIPS_CACHE_MODE
45092bbd64eSDaniel Schwierzeck
45192bbd64eSDaniel Schwierzeck		Cache operation mode for the MIPS CPU.
45292bbd64eSDaniel Schwierzeck		See also arch/mips/include/asm/mipsregs.h.
45392bbd64eSDaniel Schwierzeck		Possible values are:
45492bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_NO_WA
45592bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_WA
45692bbd64eSDaniel Schwierzeck			CONF_CM_UNCACHED
45792bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_NONCOHERENT
45892bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_CE
45992bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_COW
46092bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_CUW
46192bbd64eSDaniel Schwierzeck			CONF_CM_CACHABLE_ACCELERATED
46292bbd64eSDaniel Schwierzeck
46392bbd64eSDaniel Schwierzeck		CONFIG_SYS_XWAY_EBU_BOOTCFG
46492bbd64eSDaniel Schwierzeck
46592bbd64eSDaniel Schwierzeck		Special option for Lantiq XWAY SoCs for booting from NOR flash.
46692bbd64eSDaniel Schwierzeck		See also arch/mips/cpu/mips32/start.S.
46792bbd64eSDaniel Schwierzeck
46892bbd64eSDaniel Schwierzeck		CONFIG_XWAY_SWAP_BYTES
46992bbd64eSDaniel Schwierzeck
47092bbd64eSDaniel Schwierzeck		Enable compilation of tools/xway-swap-bytes needed for Lantiq
47192bbd64eSDaniel Schwierzeck		XWAY SoCs for booting from NOR flash. The U-Boot image needs to
47292bbd64eSDaniel Schwierzeck		be swapped if a flash programmer is used.
47392bbd64eSDaniel Schwierzeck
474b67d8816SChristian Riesch- ARM options:
475b67d8816SChristian Riesch		CONFIG_SYS_EXCEPTION_VECTORS_HIGH
476b67d8816SChristian Riesch
477b67d8816SChristian Riesch		Select high exception vectors of the ARM core, e.g., do not
478b67d8816SChristian Riesch		clear the V bit of the c1 register of CP15.
479b67d8816SChristian Riesch
4805356f545SAneesh V		CONFIG_SYS_THUMB_BUILD
4815356f545SAneesh V
4825356f545SAneesh V		Use this flag to build U-Boot using the Thumb instruction
4835356f545SAneesh V		set for ARM architectures. Thumb instruction set provides
4845356f545SAneesh V		better code density. For ARM architectures that support
4855356f545SAneesh V		Thumb2 this flag will result in Thumb2 code generated by
4865356f545SAneesh V		GCC.
4875356f545SAneesh V
4885da627a4Swdenk- Linux Kernel Interface:
489c609719bSwdenk		CONFIG_CLOCKS_IN_MHZ
490c609719bSwdenk
491c609719bSwdenk		U-Boot stores all clock information in Hz
492c609719bSwdenk		internally. For binary compatibility with older Linux
493c609719bSwdenk		kernels (which expect the clocks passed in the
494c609719bSwdenk		bd_info data to be in MHz) the environment variable
495c609719bSwdenk		"clocks_in_mhz" can be defined so that U-Boot
496c609719bSwdenk		converts clock data to MHZ before passing it to the
497c609719bSwdenk		Linux kernel.
498c609719bSwdenk		When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
499c609719bSwdenk		"clocks_in_mhz=1" is automatically included in the
500c609719bSwdenk		default environment.
501c609719bSwdenk
5025da627a4Swdenk		CONFIG_MEMSIZE_IN_BYTES		[relevant for MIPS only]
5035da627a4Swdenk
50411ccc33fSMarcel Ziswiler		When transferring memsize parameter to linux, some versions
5055da627a4Swdenk		expect it to be in bytes, others in MB.
5065da627a4Swdenk		Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
5075da627a4Swdenk
508fec6d9eeSGerald Van Baren		CONFIG_OF_LIBFDT
509f57f70aaSWolfgang Denk
510f57f70aaSWolfgang Denk		New kernel versions are expecting firmware settings to be
511213bf8c8SGerald Van Baren		passed using flattened device trees (based on open firmware
512213bf8c8SGerald Van Baren		concepts).
513213bf8c8SGerald Van Baren
514213bf8c8SGerald Van Baren		CONFIG_OF_LIBFDT
515213bf8c8SGerald Van Baren		 * New libfdt-based support
516213bf8c8SGerald Van Baren		 * Adds the "fdt" command
5173bb342fcSKim Phillips		 * The bootm command automatically updates the fdt
518213bf8c8SGerald Van Baren
519b55ae402SMarcel Ziswiler		OF_CPU - The proper name of the cpus node (only required for
520b55ae402SMarcel Ziswiler			MPC512X and MPC5xxx based boards).
521b55ae402SMarcel Ziswiler		OF_SOC - The proper name of the soc node (only required for
522b55ae402SMarcel Ziswiler			MPC512X and MPC5xxx based boards).
523f57f70aaSWolfgang Denk		OF_TBCLK - The timebase frequency.
524c2871f03SKumar Gala		OF_STDOUT_PATH - The path to the console device
525f57f70aaSWolfgang Denk
52611ccc33fSMarcel Ziswiler		boards with QUICC Engines require OF_QE to set UCC MAC
52711ccc33fSMarcel Ziswiler		addresses
5283bb342fcSKim Phillips
5294e253137SKumar Gala		CONFIG_OF_BOARD_SETUP
5304e253137SKumar Gala
5314e253137SKumar Gala		Board code has addition modification that it wants to make
5324e253137SKumar Gala		to the flat device tree before handing it off to the kernel
5336705d81eSwdenk
5340267768eSMatthew McClintock		CONFIG_OF_BOOT_CPU
5350267768eSMatthew McClintock
53611ccc33fSMarcel Ziswiler		This define fills in the correct boot CPU in the boot
5370267768eSMatthew McClintock		param header, the default value is zero if undefined.
5380267768eSMatthew McClintock
5393887c3fbSHeiko Schocher		CONFIG_OF_IDE_FIXUP
5403887c3fbSHeiko Schocher
5413887c3fbSHeiko Schocher		U-Boot can detect if an IDE device is present or not.
5423887c3fbSHeiko Schocher		If not, and this new config option is activated, U-Boot
5433887c3fbSHeiko Schocher		removes the ATA node from the DTS before booting Linux,
5443887c3fbSHeiko Schocher		so the Linux IDE driver does not probe the device and
5453887c3fbSHeiko Schocher		crash. This is needed for buggy hardware (uc101) where
5463887c3fbSHeiko Schocher		no pull down resistor is connected to the signal IDE5V_DD7.
5473887c3fbSHeiko Schocher
5487eb29398SIgor Grinberg		CONFIG_MACH_TYPE	[relevant for ARM only][mandatory]
5497eb29398SIgor Grinberg
5507eb29398SIgor Grinberg		This setting is mandatory for all boards that have only one
5517eb29398SIgor Grinberg		machine type and must be used to specify the machine type
5527eb29398SIgor Grinberg		number as it appears in the ARM machine registry
5537eb29398SIgor Grinberg		(see http://www.arm.linux.org.uk/developer/machines/).
5547eb29398SIgor Grinberg		Only boards that have multiple machine types supported
5557eb29398SIgor Grinberg		in a single configuration file and the machine type is
5567eb29398SIgor Grinberg		runtime discoverable, do not have to use this setting.
5577eb29398SIgor Grinberg
5580b2f4ecaSNiklaus Giger- vxWorks boot parameters:
5590b2f4ecaSNiklaus Giger
5600b2f4ecaSNiklaus Giger		bootvx constructs a valid bootline using the following
5610b2f4ecaSNiklaus Giger		environments variables: bootfile, ipaddr, serverip, hostname.
5620b2f4ecaSNiklaus Giger		It loads the vxWorks image pointed bootfile.
5630b2f4ecaSNiklaus Giger
5640b2f4ecaSNiklaus Giger		CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
5650b2f4ecaSNiklaus Giger		CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
5660b2f4ecaSNiklaus Giger		CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
5670b2f4ecaSNiklaus Giger		CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
5680b2f4ecaSNiklaus Giger
5690b2f4ecaSNiklaus Giger		CONFIG_SYS_VXWORKS_ADD_PARAMS
5700b2f4ecaSNiklaus Giger
5710b2f4ecaSNiklaus Giger		Add it at the end of the bootline. E.g "u=username pw=secret"
5720b2f4ecaSNiklaus Giger
5730b2f4ecaSNiklaus Giger		Note: If a "bootargs" environment is defined, it will overwride
5740b2f4ecaSNiklaus Giger		the defaults discussed just above.
5750b2f4ecaSNiklaus Giger
5762c451f78SAneesh V- Cache Configuration:
5772c451f78SAneesh V		CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
5782c451f78SAneesh V		CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
5792c451f78SAneesh V		CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
5802c451f78SAneesh V
58193bc2193SAneesh V- Cache Configuration for ARM:
58293bc2193SAneesh V		CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
58393bc2193SAneesh V				      controller
58493bc2193SAneesh V		CONFIG_SYS_PL310_BASE - Physical base address of PL310
58593bc2193SAneesh V					controller register space
58693bc2193SAneesh V
5876705d81eSwdenk- Serial Ports:
58848d0192fSAndreas Engel		CONFIG_PL010_SERIAL
5896705d81eSwdenk
5906705d81eSwdenk		Define this if you want support for Amba PrimeCell PL010 UARTs.
5916705d81eSwdenk
59248d0192fSAndreas Engel		CONFIG_PL011_SERIAL
5936705d81eSwdenk
5946705d81eSwdenk		Define this if you want support for Amba PrimeCell PL011 UARTs.
5956705d81eSwdenk
5966705d81eSwdenk		CONFIG_PL011_CLOCK
5976705d81eSwdenk
5986705d81eSwdenk		If you have Amba PrimeCell PL011 UARTs, set this variable to
5996705d81eSwdenk		the clock speed of the UARTs.
6006705d81eSwdenk
6016705d81eSwdenk		CONFIG_PL01x_PORTS
6026705d81eSwdenk
6036705d81eSwdenk		If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
6046705d81eSwdenk		define this to a list of base addresses for each (supported)
6056705d81eSwdenk		port. See e.g. include/configs/versatile.h
6066705d81eSwdenk
607910f1ae3SJohn Rigby		CONFIG_PL011_SERIAL_RLCR
608910f1ae3SJohn Rigby
609910f1ae3SJohn Rigby		Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
610910f1ae3SJohn Rigby		have separate receive and transmit line control registers.  Set
611910f1ae3SJohn Rigby		this variable to initialize the extra register.
612910f1ae3SJohn Rigby
613910f1ae3SJohn Rigby		CONFIG_PL011_SERIAL_FLUSH_ON_INIT
614910f1ae3SJohn Rigby
615910f1ae3SJohn Rigby		On some platforms (e.g. U8500) U-Boot is loaded by a second stage
616910f1ae3SJohn Rigby		boot loader that has already initialized the UART.  Define this
617910f1ae3SJohn Rigby		variable to flush the UART at init time.
618910f1ae3SJohn Rigby
6197de0fe1aSJavier Martinez Canillas		CONFIG_SYS_NS16550_BROKEN_TEMT
6207de0fe1aSJavier Martinez Canillas
6217de0fe1aSJavier Martinez Canillas		16550 UART set the Transmitter Empty (TEMT) Bit when all output
6227de0fe1aSJavier Martinez Canillas		has finished and the transmitter is totally empty. U-Boot waits
6237de0fe1aSJavier Martinez Canillas		for this bit to be set to initialize the serial console. On some
6247de0fe1aSJavier Martinez Canillas		broken platforms this bit is not set in SPL making U-Boot to
6257de0fe1aSJavier Martinez Canillas		hang while waiting for TEMT. Define this option to avoid it.
6267de0fe1aSJavier Martinez Canillas
6276705d81eSwdenk
628c609719bSwdenk- Console Interface:
629c609719bSwdenk		Depending on board, define exactly one serial port
630c609719bSwdenk		(like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
631c609719bSwdenk		CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
632c609719bSwdenk		console by defining CONFIG_8xx_CONS_NONE
633c609719bSwdenk
634c609719bSwdenk		Note: if CONFIG_8xx_CONS_NONE is defined, the serial
635c609719bSwdenk		port routines must be defined elsewhere
636c609719bSwdenk		(i.e. serial_init(), serial_getc(), ...)
637c609719bSwdenk
638c609719bSwdenk		CONFIG_CFB_CONSOLE
639c609719bSwdenk		Enables console device for a color framebuffer. Needs following
640c53043b7SWolfgang Denk		defines (cf. smiLynxEM, i8042)
641c609719bSwdenk			VIDEO_FB_LITTLE_ENDIAN	graphic memory organisation
642c609719bSwdenk						(default big endian)
643c609719bSwdenk			VIDEO_HW_RECTFILL	graphic chip supports
644c609719bSwdenk						rectangle fill
645c609719bSwdenk						(cf. smiLynxEM)
646c609719bSwdenk			VIDEO_HW_BITBLT		graphic chip supports
647c609719bSwdenk						bit-blit (cf. smiLynxEM)
648c609719bSwdenk			VIDEO_VISIBLE_COLS	visible pixel columns
649c609719bSwdenk						(cols=pitch)
650c609719bSwdenk			VIDEO_VISIBLE_ROWS	visible pixel rows
651c609719bSwdenk			VIDEO_PIXEL_SIZE	bytes per pixel
652c609719bSwdenk			VIDEO_DATA_FORMAT	graphic data format
653c609719bSwdenk						(0-5, cf. cfb_console.c)
654c609719bSwdenk			VIDEO_FB_ADRS		framebuffer address
655c609719bSwdenk			VIDEO_KBD_INIT_FCT	keyboard int fct
656c609719bSwdenk						(i.e. i8042_kbd_init())
657c609719bSwdenk			VIDEO_TSTC_FCT		test char fct
658c609719bSwdenk						(i.e. i8042_tstc)
659c609719bSwdenk			VIDEO_GETC_FCT		get char fct
660c609719bSwdenk						(i.e. i8042_getc)
661c609719bSwdenk			CONFIG_CONSOLE_CURSOR	cursor drawing on/off
662c609719bSwdenk						(requires blink timer
663c609719bSwdenk						cf. i8042.c)
6646d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
665c609719bSwdenk			CONFIG_CONSOLE_TIME	display time/date info in
666c609719bSwdenk						upper right corner
667602ad3b3SJon Loeliger						(requires CONFIG_CMD_DATE)
668c609719bSwdenk			CONFIG_VIDEO_LOGO	display Linux logo in
669c609719bSwdenk						upper left corner
670a6c7ad2fSwdenk			CONFIG_VIDEO_BMP_LOGO	use bmp_logo.h instead of
671a6c7ad2fSwdenk						linux_logo.h for logo.
672a6c7ad2fSwdenk						Requires CONFIG_VIDEO_LOGO
673c609719bSwdenk			CONFIG_CONSOLE_EXTRA_INFO
67411ccc33fSMarcel Ziswiler						additional board info beside
675c609719bSwdenk						the logo
676c609719bSwdenk
67733a35bbbSPali Rohár		When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
67833a35bbbSPali Rohár		a limited number of ANSI escape sequences (cursor control,
67933a35bbbSPali Rohár		erase functions and limited graphics rendition control).
68033a35bbbSPali Rohár
681c609719bSwdenk		When CONFIG_CFB_CONSOLE is defined, video console is
682c609719bSwdenk		default i/o. Serial console can be forced with
683c609719bSwdenk		environment 'console=serial'.
684c609719bSwdenk
685a3ad8e26Swdenk		When CONFIG_SILENT_CONSOLE is defined, all console
686a3ad8e26Swdenk		messages (by U-Boot and Linux!) can be silenced with
687a3ad8e26Swdenk		the "silent" environment variable. See
688a3ad8e26Swdenk		doc/README.silent for more information.
689a3ad8e26Swdenk
690c609719bSwdenk- Console Baudrate:
691c609719bSwdenk		CONFIG_BAUDRATE - in bps
692c609719bSwdenk		Select one of the baudrates listed in
6936d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_BAUDRATE_TABLE, see below.
6946d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
695c609719bSwdenk
696c92fac91SHeiko Schocher- Console Rx buffer length
697c92fac91SHeiko Schocher		With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
698c92fac91SHeiko Schocher		the maximum receive buffer length for the SMC.
6992b3f12c2SHeiko Schocher		This option is actual only for 82xx and 8xx possible.
700c92fac91SHeiko Schocher		If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
701c92fac91SHeiko Schocher		must be defined, to setup the maximum idle timeout for
702c92fac91SHeiko Schocher		the SMC.
703c92fac91SHeiko Schocher
7049558b48aSGraeme Russ- Pre-Console Buffer:
7059558b48aSGraeme Russ		Prior to the console being initialised (i.e. serial UART
7069558b48aSGraeme Russ		initialised etc) all console output is silently discarded.
7079558b48aSGraeme Russ		Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
7089558b48aSGraeme Russ		buffer any console messages prior to the console being
7099558b48aSGraeme Russ		initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
7109558b48aSGraeme Russ		bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
7119558b48aSGraeme Russ		a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
7129558b48aSGraeme Russ		bytes are output before the console is initialised, the
7139558b48aSGraeme Russ		earlier bytes are discarded.
7149558b48aSGraeme Russ
7159558b48aSGraeme Russ		'Sane' compilers will generate smaller code if
7169558b48aSGraeme Russ		CONFIG_PRE_CON_BUF_SZ is a power of 2
7179558b48aSGraeme Russ
718046a37bdSSonny Rao- Safe printf() functions
719046a37bdSSonny Rao		Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
720046a37bdSSonny Rao		the printf() functions. These are defined in
721046a37bdSSonny Rao		include/vsprintf.h and include snprintf(), vsnprintf() and
722046a37bdSSonny Rao		so on. Code size increase is approximately 300-500 bytes.
723046a37bdSSonny Rao		If this option is not given then these functions will
724046a37bdSSonny Rao		silently discard their buffer size argument - this means
725046a37bdSSonny Rao		you are not getting any overflow checking in this case.
726046a37bdSSonny Rao
727c609719bSwdenk- Boot Delay:	CONFIG_BOOTDELAY - in seconds
728c609719bSwdenk		Delay before automatically booting the default image;
729c609719bSwdenk		set to -1 to disable autoboot.
73093d7212fSJoe Hershberger		set to -2 to autoboot with no delay and not check for abort
73193d7212fSJoe Hershberger		(even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
732c609719bSwdenk
733c609719bSwdenk		See doc/README.autoboot for these options that
734c609719bSwdenk		work with CONFIG_BOOTDELAY. None are required.
735c609719bSwdenk		CONFIG_BOOT_RETRY_TIME
736c609719bSwdenk		CONFIG_BOOT_RETRY_MIN
737c609719bSwdenk		CONFIG_AUTOBOOT_KEYED
738c609719bSwdenk		CONFIG_AUTOBOOT_PROMPT
739c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR
740c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR
741c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR2
742c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR2
743c609719bSwdenk		CONFIG_ZERO_BOOTDELAY_CHECK
744c609719bSwdenk		CONFIG_RESET_TO_RETRY
745c609719bSwdenk
746c609719bSwdenk- Autoboot Command:
747c609719bSwdenk		CONFIG_BOOTCOMMAND
748c609719bSwdenk		Only needed when CONFIG_BOOTDELAY is enabled;
749c609719bSwdenk		define a command string that is automatically executed
750c609719bSwdenk		when no character is read on the console interface
751c609719bSwdenk		within "Boot Delay" after reset.
752c609719bSwdenk
753c609719bSwdenk		CONFIG_BOOTARGS
754c609719bSwdenk		This can be used to pass arguments to the bootm
755c609719bSwdenk		command. The value of CONFIG_BOOTARGS goes into the
756c609719bSwdenk		environment value "bootargs".
757c609719bSwdenk
758c609719bSwdenk		CONFIG_RAMBOOT and CONFIG_NFSBOOT
759c609719bSwdenk		The value of these goes into the environment as
760c609719bSwdenk		"ramboot" and "nfsboot" respectively, and can be used
761c609719bSwdenk		as a convenience, when switching between booting from
76211ccc33fSMarcel Ziswiler		RAM and NFS.
763c609719bSwdenk
764c609719bSwdenk- Pre-Boot Commands:
765c609719bSwdenk		CONFIG_PREBOOT
766c609719bSwdenk
767c609719bSwdenk		When this option is #defined, the existence of the
768c609719bSwdenk		environment variable "preboot" will be checked
769c609719bSwdenk		immediately before starting the CONFIG_BOOTDELAY
770c609719bSwdenk		countdown and/or running the auto-boot command resp.
771c609719bSwdenk		entering interactive mode.
772c609719bSwdenk
773c609719bSwdenk		This feature is especially useful when "preboot" is
774c609719bSwdenk		automatically generated or modified. For an example
775c609719bSwdenk		see the LWMON board specific code: here "preboot" is
776c609719bSwdenk		modified when the user holds down a certain
777c609719bSwdenk		combination of keys on the (special) keyboard when
778c609719bSwdenk		booting the systems
779c609719bSwdenk
780c609719bSwdenk- Serial Download Echo Mode:
781c609719bSwdenk		CONFIG_LOADS_ECHO
782c609719bSwdenk		If defined to 1, all characters received during a
783c609719bSwdenk		serial download (using the "loads" command) are
784c609719bSwdenk		echoed back. This might be needed by some terminal
785c609719bSwdenk		emulations (like "cu"), but may as well just take
786c609719bSwdenk		time on others. This setting #define's the initial
787c609719bSwdenk		value of the "loads_echo" environment variable.
788c609719bSwdenk
789602ad3b3SJon Loeliger- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
790c609719bSwdenk		CONFIG_KGDB_BAUDRATE
791c609719bSwdenk		Select one of the baudrates listed in
7926d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_BAUDRATE_TABLE, see below.
793c609719bSwdenk
794c609719bSwdenk- Monitor Functions:
795602ad3b3SJon Loeliger		Monitor commands can be included or excluded
796602ad3b3SJon Loeliger		from the build by using the #include files
797c6c621bdSStephen Warren		<config_cmd_all.h> and #undef'ing unwanted
798c6c621bdSStephen Warren		commands, or using <config_cmd_default.h>
799602ad3b3SJon Loeliger		and augmenting with additional #define's
800602ad3b3SJon Loeliger		for wanted commands.
801c609719bSwdenk
802602ad3b3SJon Loeliger		The default command configuration includes all commands
803602ad3b3SJon Loeliger		except those marked below with a "*".
804602ad3b3SJon Loeliger
805602ad3b3SJon Loeliger		CONFIG_CMD_ASKENV	* ask for env variable
806602ad3b3SJon Loeliger		CONFIG_CMD_BDI		  bdinfo
807602ad3b3SJon Loeliger		CONFIG_CMD_BEDBUG	* Include BedBug Debugger
808602ad3b3SJon Loeliger		CONFIG_CMD_BMP		* BMP support
809602ad3b3SJon Loeliger		CONFIG_CMD_BSP		* Board specific commands
810602ad3b3SJon Loeliger		CONFIG_CMD_BOOTD	  bootd
811602ad3b3SJon Loeliger		CONFIG_CMD_CACHE	* icache, dcache
812602ad3b3SJon Loeliger		CONFIG_CMD_CONSOLE	  coninfo
813710b9938SMike Frysinger		CONFIG_CMD_CRC32	* crc32
814602ad3b3SJon Loeliger		CONFIG_CMD_DATE		* support for RTC, date/time...
815602ad3b3SJon Loeliger		CONFIG_CMD_DHCP		* DHCP support
816602ad3b3SJon Loeliger		CONFIG_CMD_DIAG		* Diagnostics
817a7c93104SPeter Tyser		CONFIG_CMD_DS4510	* ds4510 I2C gpio commands
818a7c93104SPeter Tyser		CONFIG_CMD_DS4510_INFO	* ds4510 I2C info command
819a7c93104SPeter Tyser		CONFIG_CMD_DS4510_MEM	* ds4510 I2C eeprom/sram commansd
820a7c93104SPeter Tyser		CONFIG_CMD_DS4510_RST	* ds4510 I2C rst command
821602ad3b3SJon Loeliger		CONFIG_CMD_DTT		* Digital Therm and Thermostat
822602ad3b3SJon Loeliger		CONFIG_CMD_ECHO		  echo arguments
823246c6922SPeter Tyser		CONFIG_CMD_EDITENV	  edit env variable
824602ad3b3SJon Loeliger		CONFIG_CMD_EEPROM	* EEPROM read/write support
825602ad3b3SJon Loeliger		CONFIG_CMD_ELF		* bootelf, bootvx
8265e2b3e0cSJoe Hershberger		CONFIG_CMD_ENV_CALLBACK	* display details about env callbacks
827fffad71bSJoe Hershberger		CONFIG_CMD_ENV_FLAGS	* display details about env flags
8280c79cda0SMike Frysinger		CONFIG_CMD_EXPORTENV	* export the environment
82903e2ecf6SStephen Warren		CONFIG_CMD_EXT2		* ext2 command support
83003e2ecf6SStephen Warren		CONFIG_CMD_EXT4		* ext4 command support
831bdab39d3SMike Frysinger		CONFIG_CMD_SAVEENV	  saveenv
832602ad3b3SJon Loeliger		CONFIG_CMD_FDC		* Floppy Disk Support
83303e2ecf6SStephen Warren		CONFIG_CMD_FAT		* FAT command support
834602ad3b3SJon Loeliger		CONFIG_CMD_FDOS		* Dos diskette Support
835602ad3b3SJon Loeliger		CONFIG_CMD_FLASH	  flinfo, erase, protect
836602ad3b3SJon Loeliger		CONFIG_CMD_FPGA		  FPGA device initialization support
83753fdc7efSAnton Staaf		CONFIG_CMD_GETTIME	* Get time since boot
838a641b979SMike Frysinger		CONFIG_CMD_GO		* the 'go' command (exec code)
839a000b795SKim Phillips		CONFIG_CMD_GREPENV	* search environment
840bf36c5d5SSimon Glass		CONFIG_CMD_HASH		* calculate hash / digest
841602ad3b3SJon Loeliger		CONFIG_CMD_HWFLOW	* RTS/CTS hw flow control
842602ad3b3SJon Loeliger		CONFIG_CMD_I2C		* I2C serial bus support
843602ad3b3SJon Loeliger		CONFIG_CMD_IDE		* IDE harddisk support
844602ad3b3SJon Loeliger		CONFIG_CMD_IMI		  iminfo
845*8fdf1e0fSVipin Kumar		CONFIG_CMD_IMLS		  List all images found in NOR flash
846*8fdf1e0fSVipin Kumar		CONFIG_CMD_IMLS_NAND	  List all images found in NAND flash
847602ad3b3SJon Loeliger		CONFIG_CMD_IMMAP	* IMMR dump support
8480c79cda0SMike Frysinger		CONFIG_CMD_IMPORTENV	* import an environment
849c167cc02SJoe Hershberger		CONFIG_CMD_INI		* import data from an ini file into the env
850602ad3b3SJon Loeliger		CONFIG_CMD_IRQ		* irqinfo
851602ad3b3SJon Loeliger		CONFIG_CMD_ITEST	  Integer/string test of 2 values
852602ad3b3SJon Loeliger		CONFIG_CMD_JFFS2	* JFFS2 Support
853602ad3b3SJon Loeliger		CONFIG_CMD_KGDB		* kgdb
8541ba7fd25SMike Frysinger		CONFIG_CMD_LDRINFO	  ldrinfo (display Blackfin loader)
855d22c338eSJoe Hershberger		CONFIG_CMD_LINK_LOCAL	* link-local IP address auto-configuration
856d22c338eSJoe Hershberger					  (169.254.*.*)
857602ad3b3SJon Loeliger		CONFIG_CMD_LOADB	  loadb
858602ad3b3SJon Loeliger		CONFIG_CMD_LOADS	  loads
85902c9aa1dSRobin Getz		CONFIG_CMD_MD5SUM	  print md5 message digest
86002c9aa1dSRobin Getz					  (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
86115a33e49SSimon Glass		CONFIG_CMD_MEMINFO	* Display detailed memory information
862602ad3b3SJon Loeliger		CONFIG_CMD_MEMORY	  md, mm, nm, mw, cp, cmp, crc, base,
86356523f12Swdenk					  loop, loopw, mtest
864602ad3b3SJon Loeliger		CONFIG_CMD_MISC		  Misc functions like sleep etc
865602ad3b3SJon Loeliger		CONFIG_CMD_MMC		* MMC memory mapped support
866602ad3b3SJon Loeliger		CONFIG_CMD_MII		* MII utility commands
86768d7d651SStefan Roese		CONFIG_CMD_MTDPARTS	* MTD partition support
868602ad3b3SJon Loeliger		CONFIG_CMD_NAND		* NAND support
869602ad3b3SJon Loeliger		CONFIG_CMD_NET		  bootp, tftpboot, rarpboot
870e92739d3SPeter Tyser		CONFIG_CMD_PCA953X	* PCA953x I2C gpio commands
871e92739d3SPeter Tyser		CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
872602ad3b3SJon Loeliger		CONFIG_CMD_PCI		* pciinfo
873602ad3b3SJon Loeliger		CONFIG_CMD_PCMCIA		* PCMCIA support
874602ad3b3SJon Loeliger		CONFIG_CMD_PING		* send ICMP ECHO_REQUEST to network
875602ad3b3SJon Loeliger					  host
876602ad3b3SJon Loeliger		CONFIG_CMD_PORTIO	* Port I/O
877ff048ea9SKenneth Waters		CONFIG_CMD_READ		* Read raw data from partition
878602ad3b3SJon Loeliger		CONFIG_CMD_REGINFO	* Register dump
879602ad3b3SJon Loeliger		CONFIG_CMD_RUN		  run command in env variable
880602ad3b3SJon Loeliger		CONFIG_CMD_SAVES	* save S record dump
881602ad3b3SJon Loeliger		CONFIG_CMD_SCSI		* SCSI Support
882602ad3b3SJon Loeliger		CONFIG_CMD_SDRAM	* print SDRAM configuration information
883602ad3b3SJon Loeliger					  (requires CONFIG_CMD_I2C)
884602ad3b3SJon Loeliger		CONFIG_CMD_SETGETDCR	  Support for DCR Register access
885602ad3b3SJon Loeliger					  (4xx only)
886f61ec45eSEric Nelson		CONFIG_CMD_SF		* Read/write/erase SPI NOR flash
887c6b1ee66SAlexander Holler		CONFIG_CMD_SHA1SUM	  print sha1 memory digest
88802c9aa1dSRobin Getz					  (requires CONFIG_CMD_MEMORY)
88974de7aefSWolfgang Denk		CONFIG_CMD_SOURCE	  "source" command Support
890602ad3b3SJon Loeliger		CONFIG_CMD_SPI		* SPI serial bus support
8917a83af07SLuca Ceresoli		CONFIG_CMD_TFTPSRV	* TFTP transfer in server mode
8921fb7cd49SSimon Glass		CONFIG_CMD_TFTPPUT	* TFTP put command (upload)
893da83bcd7SJoe Hershberger		CONFIG_CMD_TIME		* run command and report execution time (ARM specific)
894da83bcd7SJoe Hershberger		CONFIG_CMD_TIMER	* access to the system tick timer
895602ad3b3SJon Loeliger		CONFIG_CMD_USB		* USB support
896602ad3b3SJon Loeliger		CONFIG_CMD_CDP		* Cisco Discover Protocol support
897c8339f51SMarek Vasut		CONFIG_CMD_MFSL		* Microblaze FSL support
898c609719bSwdenk
899c609719bSwdenk
900c609719bSwdenk		EXAMPLE: If you want all functions except of network
901c609719bSwdenk		support you can write:
902c609719bSwdenk
903602ad3b3SJon Loeliger		#include "config_cmd_all.h"
904602ad3b3SJon Loeliger		#undef CONFIG_CMD_NET
905c609719bSwdenk
906213bf8c8SGerald Van Baren	Other Commands:
907213bf8c8SGerald Van Baren		fdt (flattened device tree) command: CONFIG_OF_LIBFDT
908c609719bSwdenk
909c609719bSwdenk	Note:	Don't enable the "icache" and "dcache" commands
910602ad3b3SJon Loeliger		(configuration option CONFIG_CMD_CACHE) unless you know
911c609719bSwdenk		what you (and your U-Boot users) are doing. Data
912c609719bSwdenk		cache cannot be enabled on systems like the 8xx or
913c609719bSwdenk		8260 (where accesses to the IMMR region must be
914c609719bSwdenk		uncached), and it cannot be disabled on all other
915c609719bSwdenk		systems where we (mis-) use the data cache to hold an
916c609719bSwdenk		initial stack and some data.
917c609719bSwdenk
918c609719bSwdenk
919c609719bSwdenk		XXX - this list needs to get updated!
920c609719bSwdenk
92145ba8077SSimon Glass- Device tree:
92245ba8077SSimon Glass		CONFIG_OF_CONTROL
92345ba8077SSimon Glass		If this variable is defined, U-Boot will use a device tree
92445ba8077SSimon Glass		to configure its devices, instead of relying on statically
92545ba8077SSimon Glass		compiled #defines in the board file. This option is
92645ba8077SSimon Glass		experimental and only available on a few boards. The device
92745ba8077SSimon Glass		tree is available in the global data as gd->fdt_blob.
92845ba8077SSimon Glass
9292c0f79e4SSimon Glass		U-Boot needs to get its device tree from somewhere. This can
9302c0f79e4SSimon Glass		be done using one of the two options below:
931bbb0b128SSimon Glass
932bbb0b128SSimon Glass		CONFIG_OF_EMBED
933bbb0b128SSimon Glass		If this variable is defined, U-Boot will embed a device tree
934bbb0b128SSimon Glass		binary in its image. This device tree file should be in the
935bbb0b128SSimon Glass		board directory and called <soc>-<board>.dts. The binary file
936bbb0b128SSimon Glass		is then picked up in board_init_f() and made available through
937bbb0b128SSimon Glass		the global data structure as gd->blob.
93845ba8077SSimon Glass
9392c0f79e4SSimon Glass		CONFIG_OF_SEPARATE
9402c0f79e4SSimon Glass		If this variable is defined, U-Boot will build a device tree
9412c0f79e4SSimon Glass		binary. It will be called u-boot.dtb. Architecture-specific
9422c0f79e4SSimon Glass		code will locate it at run-time. Generally this works by:
9432c0f79e4SSimon Glass
9442c0f79e4SSimon Glass			cat u-boot.bin u-boot.dtb >image.bin
9452c0f79e4SSimon Glass
9462c0f79e4SSimon Glass		and in fact, U-Boot does this for you, creating a file called
9472c0f79e4SSimon Glass		u-boot-dtb.bin which is useful in the common case. You can
9482c0f79e4SSimon Glass		still use the individual files if you need something more
9492c0f79e4SSimon Glass		exotic.
9502c0f79e4SSimon Glass
951c609719bSwdenk- Watchdog:
952c609719bSwdenk		CONFIG_WATCHDOG
953c609719bSwdenk		If this variable is defined, it enables watchdog
9546abe6fb6SDetlev Zundel		support for the SoC. There must be support in the SoC
9556abe6fb6SDetlev Zundel		specific code for a watchdog. For the 8xx and 8260
9566abe6fb6SDetlev Zundel		CPUs, the SIU Watchdog feature is enabled in the SYPCR
9576abe6fb6SDetlev Zundel		register.  When supported for a specific SoC is
9586abe6fb6SDetlev Zundel		available, then no further board specific code should
9596abe6fb6SDetlev Zundel		be needed to use it.
9606abe6fb6SDetlev Zundel
9616abe6fb6SDetlev Zundel		CONFIG_HW_WATCHDOG
9626abe6fb6SDetlev Zundel		When using a watchdog circuitry external to the used
9636abe6fb6SDetlev Zundel		SoC, then define this variable and provide board
9646abe6fb6SDetlev Zundel		specific code for the "hw_watchdog_reset" function.
965c609719bSwdenk
966c1551ea8Sstroese- U-Boot Version:
967c1551ea8Sstroese		CONFIG_VERSION_VARIABLE
968c1551ea8Sstroese		If this variable is defined, an environment variable
969c1551ea8Sstroese		named "ver" is created by U-Boot showing the U-Boot
970c1551ea8Sstroese		version as printed by the "version" command.
971a1ea8e51SBenoît Thébaudeau		Any change to this variable will be reverted at the
972a1ea8e51SBenoît Thébaudeau		next reset.
973c1551ea8Sstroese
974c609719bSwdenk- Real-Time Clock:
975c609719bSwdenk
976602ad3b3SJon Loeliger		When CONFIG_CMD_DATE is selected, the type of the RTC
977c609719bSwdenk		has to be selected, too. Define exactly one of the
978c609719bSwdenk		following options:
979c609719bSwdenk
980c609719bSwdenk		CONFIG_RTC_MPC8xx	- use internal RTC of MPC8xx
981c609719bSwdenk		CONFIG_RTC_PCF8563	- use Philips PCF8563 RTC
9824e8b7544SFabio Estevam		CONFIG_RTC_MC13XXX	- use MC13783 or MC13892 RTC
983c609719bSwdenk		CONFIG_RTC_MC146818	- use MC146818 RTC
9841cb8e980Swdenk		CONFIG_RTC_DS1307	- use Maxim, Inc. DS1307 RTC
985c609719bSwdenk		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC
9867f70e853Swdenk		CONFIG_RTC_DS1338	- use Maxim, Inc. DS1338 RTC
9873bac3513Swdenk		CONFIG_RTC_DS164x	- use Dallas DS164x RTC
9889536dfccSTor Krill		CONFIG_RTC_ISL1208	- use Intersil ISL1208 RTC
9894c0d4c3bSwdenk		CONFIG_RTC_MAX6900	- use Maxim, Inc. MAX6900 RTC
9906d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_RTC_DS1337_NOOSC	- Turn off the OSC output for DS1337
99171d19f30SHeiko Schocher		CONFIG_SYS_RV3029_TCR	- enable trickle charger on
99271d19f30SHeiko Schocher					  RV3029 RTC.
993c609719bSwdenk
994b37c7e5eSwdenk		Note that if the RTC uses I2C, then the I2C interface
995b37c7e5eSwdenk		must also be configured. See I2C Support, below.
996b37c7e5eSwdenk
997e92739d3SPeter Tyser- GPIO Support:
998e92739d3SPeter Tyser		CONFIG_PCA953X		- use NXP's PCA953X series I2C GPIO
999e92739d3SPeter Tyser		CONFIG_PCA953X_INFO	- enable pca953x info command
1000e92739d3SPeter Tyser
10015dec49caSChris Packham		The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
10025dec49caSChris Packham		chip-ngpio pairs that tell the PCA953X driver the number of
10035dec49caSChris Packham		pins supported by a particular chip.
10045dec49caSChris Packham
1005e92739d3SPeter Tyser		Note that if the GPIO device uses I2C, then the I2C interface
1006e92739d3SPeter Tyser		must also be configured. See I2C Support, below.
1007e92739d3SPeter Tyser
1008c609719bSwdenk- Timestamp Support:
1009c609719bSwdenk
1010c609719bSwdenk		When CONFIG_TIMESTAMP is selected, the timestamp
1011c609719bSwdenk		(date and time) of an image is printed by image
1012c609719bSwdenk		commands like bootm or iminfo. This option is
1013602ad3b3SJon Loeliger		automatically enabled when you select CONFIG_CMD_DATE .
1014c609719bSwdenk
1015923c46f9SKarl O. Pinc- Partition Labels (disklabels) Supported:
1016923c46f9SKarl O. Pinc		Zero or more of the following:
1017923c46f9SKarl O. Pinc		CONFIG_MAC_PARTITION   Apple's MacOS partition table.
1018923c46f9SKarl O. Pinc		CONFIG_DOS_PARTITION   MS Dos partition table, traditional on the
1019923c46f9SKarl O. Pinc				       Intel architecture, USB sticks, etc.
1020923c46f9SKarl O. Pinc		CONFIG_ISO_PARTITION   ISO partition table, used on CDROM etc.
1021923c46f9SKarl O. Pinc		CONFIG_EFI_PARTITION   GPT partition table, common when EFI is the
1022923c46f9SKarl O. Pinc				       bootloader.  Note 2TB partition limit; see
1023923c46f9SKarl O. Pinc				       disk/part_efi.c
1024923c46f9SKarl O. Pinc		CONFIG_MTD_PARTITIONS  Memory Technology Device partition table.
1025c609719bSwdenk
1026602ad3b3SJon Loeliger		If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1027218ca724SWolfgang Denk		CONFIG_CMD_SCSI) you must configure support for at
1028923c46f9SKarl O. Pinc		least one non-MTD partition type as well.
1029c609719bSwdenk
1030c609719bSwdenk- IDE Reset method:
10314d13cbadSwdenk		CONFIG_IDE_RESET_ROUTINE - this is defined in several
10324d13cbadSwdenk		board configurations files but used nowhere!
1033c609719bSwdenk
10344d13cbadSwdenk		CONFIG_IDE_RESET - is this is defined, IDE Reset will
10354d13cbadSwdenk		be performed by calling the function
10364d13cbadSwdenk			ide_set_reset(int reset)
10374d13cbadSwdenk		which has to be defined in a board specific file
1038c609719bSwdenk
1039c609719bSwdenk- ATAPI Support:
1040c609719bSwdenk		CONFIG_ATAPI
1041c609719bSwdenk
1042c609719bSwdenk		Set this to enable ATAPI support.
1043c609719bSwdenk
1044c40b2956Swdenk- LBA48 Support
1045c40b2956Swdenk		CONFIG_LBA48
1046c40b2956Swdenk
1047c40b2956Swdenk		Set this to enable support for disks larger than 137GB
10484b142febSHeiko Schocher		Also look at CONFIG_SYS_64BIT_LBA.
1049c40b2956Swdenk		Whithout these , LBA48 support uses 32bit variables and will 'only'
1050c40b2956Swdenk		support disks up to 2.1TB.
1051c40b2956Swdenk
10526d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_64BIT_LBA:
1053c40b2956Swdenk			When enabled, makes the IDE subsystem use 64bit sector addresses.
1054c40b2956Swdenk			Default is 32bit.
1055c40b2956Swdenk
1056c609719bSwdenk- SCSI Support:
1057c609719bSwdenk		At the moment only there is only support for the
1058c609719bSwdenk		SYM53C8XX SCSI controller; define
1059c609719bSwdenk		CONFIG_SCSI_SYM53C8XX to enable it.
1060c609719bSwdenk
10616d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
10626d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
10636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1064c609719bSwdenk		maximum numbers of LUNs, SCSI ID's and target
1065c609719bSwdenk		devices.
10666d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1067c609719bSwdenk
1068447c031bSStefan Reinauer                The environment variable 'scsidevs' is set to the number of
1069447c031bSStefan Reinauer                SCSI devices found during the last scan.
1070447c031bSStefan Reinauer
1071c609719bSwdenk- NETWORK Support (PCI):
1072682011ffSwdenk		CONFIG_E1000
1073ce5207e1SKyle Moffett		Support for Intel 8254x/8257x gigabit chips.
1074ce5207e1SKyle Moffett
1075ce5207e1SKyle Moffett		CONFIG_E1000_SPI
1076ce5207e1SKyle Moffett		Utility code for direct access to the SPI bus on Intel 8257x.
1077ce5207e1SKyle Moffett		This does not do anything useful unless you set at least one
1078ce5207e1SKyle Moffett		of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1079ce5207e1SKyle Moffett
1080ce5207e1SKyle Moffett		CONFIG_E1000_SPI_GENERIC
1081ce5207e1SKyle Moffett		Allow generic access to the SPI bus on the Intel 8257x, for
1082ce5207e1SKyle Moffett		example with the "sspi" command.
1083ce5207e1SKyle Moffett
1084ce5207e1SKyle Moffett		CONFIG_CMD_E1000
1085ce5207e1SKyle Moffett		Management command for E1000 devices.  When used on devices
1086ce5207e1SKyle Moffett		with SPI support you can reprogram the EEPROM from U-Boot.
1087682011ffSwdenk
1088ac3315c2SAndre Schwarz		CONFIG_E1000_FALLBACK_MAC
108911ccc33fSMarcel Ziswiler		default MAC for empty EEPROM after production.
1090ac3315c2SAndre Schwarz
1091c609719bSwdenk		CONFIG_EEPRO100
1092c609719bSwdenk		Support for Intel 82557/82559/82559ER chips.
109311ccc33fSMarcel Ziswiler		Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1094c609719bSwdenk		write routine for first time initialisation.
1095c609719bSwdenk
1096c609719bSwdenk		CONFIG_TULIP
1097c609719bSwdenk		Support for Digital 2114x chips.
1098c609719bSwdenk		Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1099c609719bSwdenk		modem chip initialisation (KS8761/QS6611).
1100c609719bSwdenk
1101c609719bSwdenk		CONFIG_NATSEMI
1102c609719bSwdenk		Support for National dp83815 chips.
1103c609719bSwdenk
1104c609719bSwdenk		CONFIG_NS8382X
1105c609719bSwdenk		Support for National dp8382[01] gigabit chips.
1106c609719bSwdenk
110745219c46Swdenk- NETWORK Support (other):
110845219c46Swdenk
1109c041e9d2SJens Scharsig		CONFIG_DRIVER_AT91EMAC
1110c041e9d2SJens Scharsig		Support for AT91RM9200 EMAC.
1111c041e9d2SJens Scharsig
1112c041e9d2SJens Scharsig			CONFIG_RMII
1113c041e9d2SJens Scharsig			Define this to use reduced MII inteface
1114c041e9d2SJens Scharsig
1115c041e9d2SJens Scharsig			CONFIG_DRIVER_AT91EMAC_QUIET
1116c041e9d2SJens Scharsig			If this defined, the driver is quiet.
1117c041e9d2SJens Scharsig			The driver doen't show link status messages.
1118c041e9d2SJens Scharsig
1119efdd7319SRob Herring		CONFIG_CALXEDA_XGMAC
1120efdd7319SRob Herring		Support for the Calxeda XGMAC device
1121efdd7319SRob Herring
11223bb46d23SAshok		CONFIG_LAN91C96
112345219c46Swdenk		Support for SMSC's LAN91C96 chips.
112445219c46Swdenk
112545219c46Swdenk			CONFIG_LAN91C96_BASE
112645219c46Swdenk			Define this to hold the physical address
112745219c46Swdenk			of the LAN91C96's I/O space
112845219c46Swdenk
112945219c46Swdenk			CONFIG_LAN91C96_USE_32_BIT
113045219c46Swdenk			Define this to enable 32 bit addressing
113145219c46Swdenk
11323bb46d23SAshok		CONFIG_SMC91111
1133f39748aeSwdenk		Support for SMSC's LAN91C111 chip
1134f39748aeSwdenk
1135f39748aeSwdenk			CONFIG_SMC91111_BASE
1136f39748aeSwdenk			Define this to hold the physical address
1137f39748aeSwdenk			of the device (I/O space)
1138f39748aeSwdenk
1139f39748aeSwdenk			CONFIG_SMC_USE_32_BIT
1140f39748aeSwdenk			Define this if data bus is 32 bits
1141f39748aeSwdenk
1142f39748aeSwdenk			CONFIG_SMC_USE_IOFUNCS
1143f39748aeSwdenk			Define this to use i/o functions instead of macros
1144f39748aeSwdenk			(some hardware wont work with macros)
1145f39748aeSwdenk
1146dc02badaSHeiko Schocher		CONFIG_DRIVER_TI_EMAC
1147dc02badaSHeiko Schocher		Support for davinci emac
1148dc02badaSHeiko Schocher
1149dc02badaSHeiko Schocher			CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1150dc02badaSHeiko Schocher			Define this if you have more then 3 PHYs.
1151dc02badaSHeiko Schocher
1152b3dbf4a5SMacpaul Lin		CONFIG_FTGMAC100
1153b3dbf4a5SMacpaul Lin		Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1154b3dbf4a5SMacpaul Lin
1155b3dbf4a5SMacpaul Lin			CONFIG_FTGMAC100_EGIGA
1156b3dbf4a5SMacpaul Lin			Define this to use GE link update with gigabit PHY.
1157b3dbf4a5SMacpaul Lin			Define this if FTGMAC100 is connected to gigabit PHY.
1158b3dbf4a5SMacpaul Lin			If your system has 10/100 PHY only, it might not occur
1159b3dbf4a5SMacpaul Lin			wrong behavior. Because PHY usually return timeout or
1160b3dbf4a5SMacpaul Lin			useless data when polling gigabit status and gigabit
1161b3dbf4a5SMacpaul Lin			control registers. This behavior won't affect the
1162b3dbf4a5SMacpaul Lin			correctnessof 10/100 link speed update.
1163b3dbf4a5SMacpaul Lin
1164c2fff331SMike Rapoport		CONFIG_SMC911X
1165557b377dSJens Gehrlein		Support for SMSC's LAN911x and LAN921x chips
1166557b377dSJens Gehrlein
1167c2fff331SMike Rapoport			CONFIG_SMC911X_BASE
1168557b377dSJens Gehrlein			Define this to hold the physical address
1169557b377dSJens Gehrlein			of the device (I/O space)
1170557b377dSJens Gehrlein
1171c2fff331SMike Rapoport			CONFIG_SMC911X_32_BIT
1172557b377dSJens Gehrlein			Define this if data bus is 32 bits
1173557b377dSJens Gehrlein
1174c2fff331SMike Rapoport			CONFIG_SMC911X_16_BIT
1175557b377dSJens Gehrlein			Define this if data bus is 16 bits. If your processor
1176557b377dSJens Gehrlein			automatically converts one 32 bit word to two 16 bit
1177c2fff331SMike Rapoport			words you may also try CONFIG_SMC911X_32_BIT.
1178557b377dSJens Gehrlein
11793d0075faSYoshihiro Shimoda		CONFIG_SH_ETHER
11803d0075faSYoshihiro Shimoda		Support for Renesas on-chip Ethernet controller
11813d0075faSYoshihiro Shimoda
11823d0075faSYoshihiro Shimoda			CONFIG_SH_ETHER_USE_PORT
11833d0075faSYoshihiro Shimoda			Define the number of ports to be used
11843d0075faSYoshihiro Shimoda
11853d0075faSYoshihiro Shimoda			CONFIG_SH_ETHER_PHY_ADDR
11863d0075faSYoshihiro Shimoda			Define the ETH PHY's address
11873d0075faSYoshihiro Shimoda
118868260aabSYoshihiro Shimoda			CONFIG_SH_ETHER_CACHE_WRITEBACK
118968260aabSYoshihiro Shimoda			If this option is set, the driver enables cache flush.
119068260aabSYoshihiro Shimoda
11915e124724SVadim Bendebury- TPM Support:
11925e124724SVadim Bendebury		CONFIG_GENERIC_LPC_TPM
11935e124724SVadim Bendebury		Support for generic parallel port TPM devices. Only one device
11945e124724SVadim Bendebury		per system is supported at this time.
11955e124724SVadim Bendebury
11965e124724SVadim Bendebury			CONFIG_TPM_TIS_BASE_ADDRESS
11975e124724SVadim Bendebury			Base address where the generic TPM device is mapped
11985e124724SVadim Bendebury			to. Contemporary x86 systems usually map it at
11995e124724SVadim Bendebury			0xfed40000.
12005e124724SVadim Bendebury
1201c609719bSwdenk- USB Support:
1202c609719bSwdenk		At the moment only the UHCI host controller is
12034d13cbadSwdenk		supported (PIP405, MIP405, MPC5200); define
1204c609719bSwdenk		CONFIG_USB_UHCI to enable it.
1205c609719bSwdenk		define CONFIG_USB_KEYBOARD to enable the USB Keyboard
120630d56faeSwdenk		and define CONFIG_USB_STORAGE to enable the USB
1207c609719bSwdenk		storage devices.
1208c609719bSwdenk		Note:
1209c609719bSwdenk		Supported are USB Keyboards and USB Floppy drives
1210c609719bSwdenk		(TEAC FD-05PUB).
12114d13cbadSwdenk		MPC5200 USB requires additional defines:
12124d13cbadSwdenk			CONFIG_USB_CLOCK
12134d13cbadSwdenk				for 528 MHz Clock: 0x0001bbbb
1214307ecb6dSEric Millbrandt			CONFIG_PSC3_USB
1215307ecb6dSEric Millbrandt				for USB on PSC3
12164d13cbadSwdenk			CONFIG_USB_CONFIG
12174d13cbadSwdenk				for differential drivers: 0x00001000
12184d13cbadSwdenk				for single ended drivers: 0x00005000
1219307ecb6dSEric Millbrandt				for differential drivers on PSC3: 0x00000100
1220307ecb6dSEric Millbrandt				for single ended drivers on PSC3: 0x00004100
12216d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_USB_EVENT_POLL
1222fdcfaa1bSZhang Wei				May be defined to allow interrupt polling
1223fdcfaa1bSZhang Wei				instead of using asynchronous interrupts
12244d13cbadSwdenk
12259ab4ce22SSimon Glass		CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
12269ab4ce22SSimon Glass		txfilltuning field in the EHCI controller on reset.
12279ab4ce22SSimon Glass
122816c8d5e7SWolfgang Denk- USB Device:
122916c8d5e7SWolfgang Denk		Define the below if you wish to use the USB console.
123016c8d5e7SWolfgang Denk		Once firmware is rebuilt from a serial console issue the
123116c8d5e7SWolfgang Denk		command "setenv stdin usbtty; setenv stdout usbtty" and
123211ccc33fSMarcel Ziswiler		attach your USB cable. The Unix command "dmesg" should print
123316c8d5e7SWolfgang Denk		it has found a new device. The environment variable usbtty
123416c8d5e7SWolfgang Denk		can be set to gserial or cdc_acm to enable your device to
123516c8d5e7SWolfgang Denk		appear to a USB host as a Linux gserial device or a
123616c8d5e7SWolfgang Denk		Common Device Class Abstract Control Model serial device.
123716c8d5e7SWolfgang Denk		If you select usbtty = gserial you should be able to enumerate
123816c8d5e7SWolfgang Denk		a Linux host by
123916c8d5e7SWolfgang Denk		# modprobe usbserial vendor=0xVendorID product=0xProductID
124016c8d5e7SWolfgang Denk		else if using cdc_acm, simply setting the environment
124116c8d5e7SWolfgang Denk		variable usbtty to be cdc_acm should suffice. The following
124216c8d5e7SWolfgang Denk		might be defined in YourBoardName.h
124316c8d5e7SWolfgang Denk
124416c8d5e7SWolfgang Denk			CONFIG_USB_DEVICE
124516c8d5e7SWolfgang Denk			Define this to build a UDC device
124616c8d5e7SWolfgang Denk
124716c8d5e7SWolfgang Denk			CONFIG_USB_TTY
124816c8d5e7SWolfgang Denk			Define this to have a tty type of device available to
124916c8d5e7SWolfgang Denk			talk to the UDC device
125016c8d5e7SWolfgang Denk
1251f9da0f89SVipin KUMAR			CONFIG_USBD_HS
1252f9da0f89SVipin KUMAR			Define this to enable the high speed support for usb
1253f9da0f89SVipin KUMAR			device and usbtty. If this feature is enabled, a routine
1254f9da0f89SVipin KUMAR			int is_usbd_high_speed(void)
1255f9da0f89SVipin KUMAR			also needs to be defined by the driver to dynamically poll
1256f9da0f89SVipin KUMAR			whether the enumeration has succeded at high speed or full
1257f9da0f89SVipin KUMAR			speed.
1258f9da0f89SVipin KUMAR
12596d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			CONFIG_SYS_CONSOLE_IS_IN_ENV
126016c8d5e7SWolfgang Denk			Define this if you want stdin, stdout &/or stderr to
126116c8d5e7SWolfgang Denk			be set to usbtty.
126216c8d5e7SWolfgang Denk
126316c8d5e7SWolfgang Denk			mpc8xx:
12646d0f6bcfSJean-Christophe PLAGNIOL-VILLARD				CONFIG_SYS_USB_EXTC_CLK 0xBLAH
126516c8d5e7SWolfgang Denk				Derive USB clock from external clock "blah"
12666d0f6bcfSJean-Christophe PLAGNIOL-VILLARD				- CONFIG_SYS_USB_EXTC_CLK 0x02
126716c8d5e7SWolfgang Denk
12686d0f6bcfSJean-Christophe PLAGNIOL-VILLARD				CONFIG_SYS_USB_BRG_CLK 0xBLAH
126916c8d5e7SWolfgang Denk				Derive USB clock from brgclk
12706d0f6bcfSJean-Christophe PLAGNIOL-VILLARD				- CONFIG_SYS_USB_BRG_CLK 0x04
127116c8d5e7SWolfgang Denk
127216c8d5e7SWolfgang Denk		If you have a USB-IF assigned VendorID then you may wish to
127316c8d5e7SWolfgang Denk		define your own vendor specific values either in BoardName.h
127416c8d5e7SWolfgang Denk		or directly in usbd_vendor_info.h. If you don't define
127516c8d5e7SWolfgang Denk		CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
127616c8d5e7SWolfgang Denk		CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
127716c8d5e7SWolfgang Denk		should pretend to be a Linux device to it's target host.
127816c8d5e7SWolfgang Denk
127916c8d5e7SWolfgang Denk			CONFIG_USBD_MANUFACTURER
128016c8d5e7SWolfgang Denk			Define this string as the name of your company for
128116c8d5e7SWolfgang Denk			- CONFIG_USBD_MANUFACTURER "my company"
128216c8d5e7SWolfgang Denk
128316c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCT_NAME
128416c8d5e7SWolfgang Denk			Define this string as the name of your product
128516c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCT_NAME "acme usb device"
128616c8d5e7SWolfgang Denk
128716c8d5e7SWolfgang Denk			CONFIG_USBD_VENDORID
128816c8d5e7SWolfgang Denk			Define this as your assigned Vendor ID from the USB
128916c8d5e7SWolfgang Denk			Implementors Forum. This *must* be a genuine Vendor ID
129016c8d5e7SWolfgang Denk			to avoid polluting the USB namespace.
129116c8d5e7SWolfgang Denk			- CONFIG_USBD_VENDORID 0xFFFF
129216c8d5e7SWolfgang Denk
129316c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCTID
129416c8d5e7SWolfgang Denk			Define this as the unique Product ID
129516c8d5e7SWolfgang Denk			for your device
129616c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCTID 0xFFFF
1297c609719bSwdenk
1298d70a560fSIgor Grinberg- ULPI Layer Support:
1299d70a560fSIgor Grinberg		The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1300d70a560fSIgor Grinberg		the generic ULPI layer. The generic layer accesses the ULPI PHY
1301d70a560fSIgor Grinberg		via the platform viewport, so you need both the genric layer and
1302d70a560fSIgor Grinberg		the viewport enabled. Currently only Chipidea/ARC based
1303d70a560fSIgor Grinberg		viewport is supported.
1304d70a560fSIgor Grinberg		To enable the ULPI layer support, define CONFIG_USB_ULPI and
1305d70a560fSIgor Grinberg		CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
13066d365ea0SLucas Stach		If your ULPI phy needs a different reference clock than the
13076d365ea0SLucas Stach		standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
13086d365ea0SLucas Stach		the appropriate value in Hz.
1309c609719bSwdenk
1310c609719bSwdenk- MMC Support:
1311c609719bSwdenk		The MMC controller on the Intel PXA is supported. To
1312c609719bSwdenk		enable this define CONFIG_MMC. The MMC can be
1313c609719bSwdenk		accessed from the boot prompt by mapping the device
1314c609719bSwdenk		to physical memory similar to flash. Command line is
1315602ad3b3SJon Loeliger		enabled with CONFIG_CMD_MMC. The MMC driver also works with
1316602ad3b3SJon Loeliger		the FAT fs. This is enabled with CONFIG_CMD_FAT.
1317c609719bSwdenk
1318afb35666SYoshihiro Shimoda		CONFIG_SH_MMCIF
1319afb35666SYoshihiro Shimoda		Support for Renesas on-chip MMCIF controller
1320afb35666SYoshihiro Shimoda
1321afb35666SYoshihiro Shimoda			CONFIG_SH_MMCIF_ADDR
1322afb35666SYoshihiro Shimoda			Define the base address of MMCIF registers
1323afb35666SYoshihiro Shimoda
1324afb35666SYoshihiro Shimoda			CONFIG_SH_MMCIF_CLK
1325afb35666SYoshihiro Shimoda			Define the clock frequency for MMCIF
1326afb35666SYoshihiro Shimoda
13276705d81eSwdenk- Journaling Flash filesystem support:
13286705d81eSwdenk		CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
13296705d81eSwdenk		CONFIG_JFFS2_NAND_DEV
13306705d81eSwdenk		Define these for a default partition on a NAND device
13316705d81eSwdenk
13326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_JFFS2_FIRST_SECTOR,
13336d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
13346705d81eSwdenk		Define these for a default partition on a NOR device
13356705d81eSwdenk
13366d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_JFFS_CUSTOM_PART
13376705d81eSwdenk		Define this to create an own partition. You have to provide a
13386705d81eSwdenk		function struct part_info* jffs2_part_info(int part_num)
13396705d81eSwdenk
13406705d81eSwdenk		If you define only one JFFS2 partition you may also want to
13416d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		#define CONFIG_SYS_JFFS_SINGLE_PART	1
13426705d81eSwdenk		to disable the command chpart. This is the default when you
13436705d81eSwdenk		have not defined a custom partition
13446705d81eSwdenk
1345c30a15e5SDonggeun Kim- FAT(File Allocation Table) filesystem write function support:
1346c30a15e5SDonggeun Kim		CONFIG_FAT_WRITE
1347656f4c65SDonggeun Kim
1348656f4c65SDonggeun Kim		Define this to enable support for saving memory data as a
1349656f4c65SDonggeun Kim		file in FAT formatted partition.
1350656f4c65SDonggeun Kim
1351656f4c65SDonggeun Kim		This will also enable the command "fatwrite" enabling the
1352656f4c65SDonggeun Kim		user to write files to FAT.
1353c30a15e5SDonggeun Kim
135484cd9327SGabe BlackCBFS (Coreboot Filesystem) support
135584cd9327SGabe Black		CONFIG_CMD_CBFS
135684cd9327SGabe Black
135784cd9327SGabe Black		Define this to enable support for reading from a Coreboot
135884cd9327SGabe Black		filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
135984cd9327SGabe Black		and cbfsload.
136084cd9327SGabe Black
1361c609719bSwdenk- Keyboard Support:
1362c609719bSwdenk		CONFIG_ISA_KEYBOARD
1363c609719bSwdenk
1364c609719bSwdenk		Define this to enable standard (PC-Style) keyboard
1365c609719bSwdenk		support
1366c609719bSwdenk
1367c609719bSwdenk		CONFIG_I8042_KBD
1368c609719bSwdenk		Standard PC keyboard driver with US (is default) and
1369c609719bSwdenk		GERMAN key layout (switch via environment 'keymap=de') support.
1370c609719bSwdenk		Export function i8042_kbd_init, i8042_tstc and i8042_getc
1371c609719bSwdenk		for cfb_console. Supports cursor blinking.
1372c609719bSwdenk
1373c609719bSwdenk- Video support:
1374c609719bSwdenk		CONFIG_VIDEO
1375c609719bSwdenk
1376c609719bSwdenk		Define this to enable video support (for output to
1377c609719bSwdenk		video).
1378c609719bSwdenk
1379c609719bSwdenk		CONFIG_VIDEO_CT69000
1380c609719bSwdenk
1381c609719bSwdenk		Enable Chips & Technologies 69000 Video chip
1382c609719bSwdenk
1383c609719bSwdenk		CONFIG_VIDEO_SMI_LYNXEM
1384eeb1b77bSwdenk		Enable Silicon Motion SMI 712/710/810 Video chip. The
1385eeb1b77bSwdenk		video output is selected via environment 'videoout'
1386eeb1b77bSwdenk		(1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1387eeb1b77bSwdenk		assumed.
1388c609719bSwdenk
1389eeb1b77bSwdenk		For the CT69000 and SMI_LYNXEM drivers, videomode is
139011ccc33fSMarcel Ziswiler		selected via environment 'videomode'. Two different ways
1391eeb1b77bSwdenk		are possible:
1392eeb1b77bSwdenk		- "videomode=num"   'num' is a standard LiLo mode numbers.
1393eeb1b77bSwdenk		Following standard modes are supported	(* is default):
1394eeb1b77bSwdenk
1395eeb1b77bSwdenk		      Colors	640x480 800x600 1024x768 1152x864 1280x1024
1396eeb1b77bSwdenk		-------------+---------------------------------------------
1397eeb1b77bSwdenk		      8 bits |	0x301*	0x303	 0x305	  0x161	    0x307
1398eeb1b77bSwdenk		     15 bits |	0x310	0x313	 0x316	  0x162	    0x319
1399eeb1b77bSwdenk		     16 bits |	0x311	0x314	 0x317	  0x163	    0x31A
1400eeb1b77bSwdenk		     24 bits |	0x312	0x315	 0x318	    ?	    0x31B
1401eeb1b77bSwdenk		-------------+---------------------------------------------
1402c609719bSwdenk		(i.e. setenv videomode 317; saveenv; reset;)
1403c609719bSwdenk
1404eeb1b77bSwdenk		- "videomode=bootargs" all the video parameters are parsed
14057817cb20SMarcel Ziswiler		from the bootargs. (See drivers/video/videomodes.c)
1406eeb1b77bSwdenk
1407eeb1b77bSwdenk
1408a6c7ad2fSwdenk		CONFIG_VIDEO_SED13806
1409a6c7ad2fSwdenk		Enable Epson SED13806 driver. This driver supports 8bpp
1410a6c7ad2fSwdenk		and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1411a6c7ad2fSwdenk		or CONFIG_VIDEO_SED13806_16BPP
1412a6c7ad2fSwdenk
14137d3053fbSTimur Tabi		CONFIG_FSL_DIU_FB
14147d3053fbSTimur Tabi		Enable the Freescale DIU video driver.	Reference boards for
14157d3053fbSTimur Tabi		SOCs that have a DIU should define this macro to enable DIU
14167d3053fbSTimur Tabi		support, and should also define these other macros:
14177d3053fbSTimur Tabi
14187d3053fbSTimur Tabi			CONFIG_SYS_DIU_ADDR
14197d3053fbSTimur Tabi			CONFIG_VIDEO
14207d3053fbSTimur Tabi			CONFIG_CMD_BMP
14217d3053fbSTimur Tabi			CONFIG_CFB_CONSOLE
14227d3053fbSTimur Tabi			CONFIG_VIDEO_SW_CURSOR
14237d3053fbSTimur Tabi			CONFIG_VGA_AS_SINGLE_DEVICE
14247d3053fbSTimur Tabi			CONFIG_VIDEO_LOGO
14257d3053fbSTimur Tabi			CONFIG_VIDEO_BMP_LOGO
14267d3053fbSTimur Tabi
1427ba8e76bdSTimur Tabi		The DIU driver will look for the 'video-mode' environment
1428ba8e76bdSTimur Tabi		variable, and if defined, enable the DIU as a console during
1429ba8e76bdSTimur Tabi		boot.  See the documentation file README.video for a
1430ba8e76bdSTimur Tabi		description of this variable.
14317d3053fbSTimur Tabi
1432058d59b0SSimon Glass		CONFIG_VIDEO_VGA
1433058d59b0SSimon Glass
1434058d59b0SSimon Glass		Enable the VGA video / BIOS for x86. The alternative if you
1435058d59b0SSimon Glass		are using coreboot is to use the coreboot frame buffer
1436058d59b0SSimon Glass		driver.
1437058d59b0SSimon Glass
1438058d59b0SSimon Glass
1439682011ffSwdenk- Keyboard Support:
1440682011ffSwdenk		CONFIG_KEYBOARD
1441682011ffSwdenk
1442682011ffSwdenk		Define this to enable a custom keyboard support.
1443682011ffSwdenk		This simply calls drv_keyboard_init() which must be
1444682011ffSwdenk		defined in your board-specific files.
1445682011ffSwdenk		The only board using this so far is RBC823.
1446a6c7ad2fSwdenk
1447c609719bSwdenk- LCD Support:	CONFIG_LCD
1448c609719bSwdenk
1449c609719bSwdenk		Define this to enable LCD support (for output to LCD
1450c609719bSwdenk		display); also select one of the supported displays
1451c609719bSwdenk		by defining one of these:
1452c609719bSwdenk
145339cf4804SStelian Pop		CONFIG_ATMEL_LCD:
145439cf4804SStelian Pop
145539cf4804SStelian Pop			HITACHI TX09D70VM1CCA, 3.5", 240x320.
145639cf4804SStelian Pop
1457fd3103bbSwdenk		CONFIG_NEC_NL6448AC33:
1458c609719bSwdenk
1459fd3103bbSwdenk			NEC NL6448AC33-18. Active, color, single scan.
1460c609719bSwdenk
1461fd3103bbSwdenk		CONFIG_NEC_NL6448BC20
1462c609719bSwdenk
1463fd3103bbSwdenk			NEC NL6448BC20-08. 6.5", 640x480.
1464fd3103bbSwdenk			Active, color, single scan.
1465fd3103bbSwdenk
1466fd3103bbSwdenk		CONFIG_NEC_NL6448BC33_54
1467fd3103bbSwdenk
1468fd3103bbSwdenk			NEC NL6448BC33-54. 10.4", 640x480.
1469c609719bSwdenk			Active, color, single scan.
1470c609719bSwdenk
1471c609719bSwdenk		CONFIG_SHARP_16x9
1472c609719bSwdenk
1473c609719bSwdenk			Sharp 320x240. Active, color, single scan.
1474c609719bSwdenk			It isn't 16x9, and I am not sure what it is.
1475c609719bSwdenk
1476c609719bSwdenk		CONFIG_SHARP_LQ64D341
1477c609719bSwdenk
1478c609719bSwdenk			Sharp LQ64D341 display, 640x480.
1479c609719bSwdenk			Active, color, single scan.
1480c609719bSwdenk
1481c609719bSwdenk		CONFIG_HLD1045
1482c609719bSwdenk
1483c609719bSwdenk			HLD1045 display, 640x480.
1484c609719bSwdenk			Active, color, single scan.
1485c609719bSwdenk
1486c609719bSwdenk		CONFIG_OPTREX_BW
1487c609719bSwdenk
1488c609719bSwdenk			Optrex	 CBL50840-2 NF-FW 99 22 M5
1489c609719bSwdenk			or
1490c609719bSwdenk			Hitachi	 LMG6912RPFC-00T
1491c609719bSwdenk			or
1492c609719bSwdenk			Hitachi	 SP14Q002
1493c609719bSwdenk
1494c609719bSwdenk			320x240. Black & white.
1495c609719bSwdenk
1496c609719bSwdenk		Normally display is black on white background; define
14976d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1498c609719bSwdenk
1499676d319eSSimon Glass		CONFIG_LCD_ALIGNMENT
1500676d319eSSimon Glass
1501676d319eSSimon Glass		Normally the LCD is page-aligned (tyically 4KB). If this is
1502676d319eSSimon Glass		defined then the LCD will be aligned to this value instead.
1503676d319eSSimon Glass		For ARM it is sometimes useful to use MMU_SECTION_SIZE
1504676d319eSSimon Glass		here, since it is cheaper to change data cache settings on
1505676d319eSSimon Glass		a per-section basis.
1506676d319eSSimon Glass
15070d89efefSSimon Glass		CONFIG_CONSOLE_SCROLL_LINES
15080d89efefSSimon Glass
15090d89efefSSimon Glass		When the console need to be scrolled, this is the number of
15100d89efefSSimon Glass		lines to scroll by. It defaults to 1. Increasing this makes
15110d89efefSSimon Glass		the console jump but can help speed up operation when scrolling
15120d89efefSSimon Glass		is slow.
1513676d319eSSimon Glass
151445d7f525STom Wai-Hong Tam		CONFIG_LCD_BMP_RLE8
151545d7f525STom Wai-Hong Tam
151645d7f525STom Wai-Hong Tam		Support drawing of RLE8-compressed bitmaps on the LCD.
151745d7f525STom Wai-Hong Tam
1518735987c5STom Wai-Hong Tam		CONFIG_I2C_EDID
1519735987c5STom Wai-Hong Tam
1520735987c5STom Wai-Hong Tam		Enables an 'i2c edid' command which can read EDID
1521735987c5STom Wai-Hong Tam		information over I2C from an attached LCD display.
1522735987c5STom Wai-Hong Tam
15237152b1d0Swdenk- Splash Screen Support: CONFIG_SPLASH_SCREEN
1524d791b1dcSwdenk
1525d791b1dcSwdenk		If this option is set, the environment is checked for
1526d791b1dcSwdenk		a variable "splashimage". If found, the usual display
1527d791b1dcSwdenk		of logo, copyright and system information on the LCD
1528e94d2cd9Swdenk		is suppressed and the BMP image at the address
1529d791b1dcSwdenk		specified in "splashimage" is loaded instead. The
1530d791b1dcSwdenk		console is redirected to the "nulldev", too. This
1531d791b1dcSwdenk		allows for a "silent" boot where a splash screen is
1532d791b1dcSwdenk		loaded very quickly after power-on.
1533d791b1dcSwdenk
15341ca298ceSMatthias Weisser		CONFIG_SPLASH_SCREEN_ALIGN
15351ca298ceSMatthias Weisser
15361ca298ceSMatthias Weisser		If this option is set the splash image can be freely positioned
15371ca298ceSMatthias Weisser		on the screen. Environment variable "splashpos" specifies the
15381ca298ceSMatthias Weisser		position as "x,y". If a positive number is given it is used as
15391ca298ceSMatthias Weisser		number of pixel from left/top. If a negative number is given it
15401ca298ceSMatthias Weisser		is used as number of pixel from right/bottom. You can also
15411ca298ceSMatthias Weisser		specify 'm' for centering the image.
15421ca298ceSMatthias Weisser
15431ca298ceSMatthias Weisser		Example:
15441ca298ceSMatthias Weisser		setenv splashpos m,m
15451ca298ceSMatthias Weisser			=> image at center of screen
15461ca298ceSMatthias Weisser
15471ca298ceSMatthias Weisser		setenv splashpos 30,20
15481ca298ceSMatthias Weisser			=> image at x = 30 and y = 20
15491ca298ceSMatthias Weisser
15501ca298ceSMatthias Weisser		setenv splashpos -10,m
15511ca298ceSMatthias Weisser			=> vertically centered image
15521ca298ceSMatthias Weisser			   at x = dspWidth - bmpWidth - 9
15531ca298ceSMatthias Weisser
155498f4a3dfSStefan Roese- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
155598f4a3dfSStefan Roese
155698f4a3dfSStefan Roese		If this option is set, additionally to standard BMP
155798f4a3dfSStefan Roese		images, gzipped BMP images can be displayed via the
155898f4a3dfSStefan Roese		splashscreen support or the bmp command.
155998f4a3dfSStefan Roese
1560d5011762SAnatolij Gustschin- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1561d5011762SAnatolij Gustschin
1562d5011762SAnatolij Gustschin		If this option is set, 8-bit RLE compressed BMP images
1563d5011762SAnatolij Gustschin		can be displayed via the splashscreen support or the
1564d5011762SAnatolij Gustschin		bmp command.
1565d5011762SAnatolij Gustschin
1566f2b96dfbSLei Wen- Do compresssing for memory range:
1567f2b96dfbSLei Wen		CONFIG_CMD_ZIP
1568f2b96dfbSLei Wen
1569f2b96dfbSLei Wen		If this option is set, it would use zlib deflate method
1570f2b96dfbSLei Wen		to compress the specified memory at its best effort.
1571f2b96dfbSLei Wen
1572c29fdfc1Swdenk- Compression support:
1573c29fdfc1Swdenk		CONFIG_BZIP2
1574c29fdfc1Swdenk
1575c29fdfc1Swdenk		If this option is set, support for bzip2 compressed
1576c29fdfc1Swdenk		images is included. If not, only uncompressed and gzip
1577c29fdfc1Swdenk		compressed images are supported.
1578c29fdfc1Swdenk
1579c29fdfc1Swdenk		NOTE: the bzip2 algorithm requires a lot of RAM, so
15806d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1581c29fdfc1Swdenk		be at least 4MB.
1582d791b1dcSwdenk
1583fc9c1727SLuigi 'Comio' Mantellini		CONFIG_LZMA
1584fc9c1727SLuigi 'Comio' Mantellini
1585fc9c1727SLuigi 'Comio' Mantellini		If this option is set, support for lzma compressed
1586fc9c1727SLuigi 'Comio' Mantellini		images is included.
1587fc9c1727SLuigi 'Comio' Mantellini
1588fc9c1727SLuigi 'Comio' Mantellini		Note: The LZMA algorithm adds between 2 and 4KB of code and it
1589fc9c1727SLuigi 'Comio' Mantellini		requires an amount of dynamic memory that is given by the
1590fc9c1727SLuigi 'Comio' Mantellini		formula:
1591fc9c1727SLuigi 'Comio' Mantellini
1592fc9c1727SLuigi 'Comio' Mantellini			(1846 + 768 << (lc + lp)) * sizeof(uint16)
1593fc9c1727SLuigi 'Comio' Mantellini
1594fc9c1727SLuigi 'Comio' Mantellini		Where lc and lp stand for, respectively, Literal context bits
1595fc9c1727SLuigi 'Comio' Mantellini		and Literal pos bits.
1596fc9c1727SLuigi 'Comio' Mantellini
1597fc9c1727SLuigi 'Comio' Mantellini		This value is upper-bounded by 14MB in the worst case. Anyway,
1598fc9c1727SLuigi 'Comio' Mantellini		for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1599fc9c1727SLuigi 'Comio' Mantellini		total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1600fc9c1727SLuigi 'Comio' Mantellini		a very small buffer.
1601fc9c1727SLuigi 'Comio' Mantellini
1602fc9c1727SLuigi 'Comio' Mantellini		Use the lzmainfo tool to determinate the lc and lp values and
1603fc9c1727SLuigi 'Comio' Mantellini		then calculate the amount of needed dynamic memory (ensuring
16046d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		the appropriate CONFIG_SYS_MALLOC_LEN value).
1605fc9c1727SLuigi 'Comio' Mantellini
160617ea1177Swdenk- MII/PHY support:
160717ea1177Swdenk		CONFIG_PHY_ADDR
160817ea1177Swdenk
160917ea1177Swdenk		The address of PHY on MII bus.
161017ea1177Swdenk
161117ea1177Swdenk		CONFIG_PHY_CLOCK_FREQ (ppc4xx)
161217ea1177Swdenk
161317ea1177Swdenk		The clock frequency of the MII bus
161417ea1177Swdenk
161517ea1177Swdenk		CONFIG_PHY_GIGE
161617ea1177Swdenk
161717ea1177Swdenk		If this option is set, support for speed/duplex
161811ccc33fSMarcel Ziswiler		detection of gigabit PHY is included.
161917ea1177Swdenk
162017ea1177Swdenk		CONFIG_PHY_RESET_DELAY
162117ea1177Swdenk
162217ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
162317ea1177Swdenk		reset before any MII register access is possible.
162417ea1177Swdenk		For such PHY, set this option to the usec delay
162517ea1177Swdenk		required. (minimum 300usec for LXT971A)
162617ea1177Swdenk
162717ea1177Swdenk		CONFIG_PHY_CMD_DELAY (ppc4xx)
162817ea1177Swdenk
162917ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
163017ea1177Swdenk		command issued before MII status register can be read
163117ea1177Swdenk
1632c609719bSwdenk- Ethernet address:
1633c609719bSwdenk		CONFIG_ETHADDR
1634c68a05feSrichardretanubun		CONFIG_ETH1ADDR
1635c609719bSwdenk		CONFIG_ETH2ADDR
1636c609719bSwdenk		CONFIG_ETH3ADDR
1637c68a05feSrichardretanubun		CONFIG_ETH4ADDR
1638c68a05feSrichardretanubun		CONFIG_ETH5ADDR
1639c609719bSwdenk
164011ccc33fSMarcel Ziswiler		Define a default value for Ethernet address to use
164111ccc33fSMarcel Ziswiler		for the respective Ethernet interface, in case this
1642c609719bSwdenk		is not determined automatically.
1643c609719bSwdenk
1644c609719bSwdenk- IP address:
1645c609719bSwdenk		CONFIG_IPADDR
1646c609719bSwdenk
1647c609719bSwdenk		Define a default value for the IP address to use for
164811ccc33fSMarcel Ziswiler		the default Ethernet interface, in case this is not
1649c609719bSwdenk		determined through e.g. bootp.
16501ebcd654SWolfgang Denk		(Environment variable "ipaddr")
1651c609719bSwdenk
1652c609719bSwdenk- Server IP address:
1653c609719bSwdenk		CONFIG_SERVERIP
1654c609719bSwdenk
1655c609719bSwdenk		Defines a default value for the IP address of a TFTP
1656c609719bSwdenk		server to contact when using the "tftboot" command.
16571ebcd654SWolfgang Denk		(Environment variable "serverip")
1658c609719bSwdenk
165997cfe861SRobin Getz		CONFIG_KEEP_SERVERADDR
166097cfe861SRobin Getz
166197cfe861SRobin Getz		Keeps the server's MAC address, in the env 'serveraddr'
166297cfe861SRobin Getz		for passing to bootargs (like Linux's netconsole option)
166397cfe861SRobin Getz
16641ebcd654SWolfgang Denk- Gateway IP address:
16651ebcd654SWolfgang Denk		CONFIG_GATEWAYIP
16661ebcd654SWolfgang Denk
16671ebcd654SWolfgang Denk		Defines a default value for the IP address of the
16681ebcd654SWolfgang Denk		default router where packets to other networks are
16691ebcd654SWolfgang Denk		sent to.
16701ebcd654SWolfgang Denk		(Environment variable "gatewayip")
16711ebcd654SWolfgang Denk
16721ebcd654SWolfgang Denk- Subnet mask:
16731ebcd654SWolfgang Denk		CONFIG_NETMASK
16741ebcd654SWolfgang Denk
16751ebcd654SWolfgang Denk		Defines a default value for the subnet mask (or
16761ebcd654SWolfgang Denk		routing prefix) which is used to determine if an IP
16771ebcd654SWolfgang Denk		address belongs to the local subnet or needs to be
16781ebcd654SWolfgang Denk		forwarded through a router.
16791ebcd654SWolfgang Denk		(Environment variable "netmask")
16801ebcd654SWolfgang Denk
168153a5c424SDavid Updegraff- Multicast TFTP Mode:
168253a5c424SDavid Updegraff		CONFIG_MCAST_TFTP
168353a5c424SDavid Updegraff
168453a5c424SDavid Updegraff		Defines whether you want to support multicast TFTP as per
168553a5c424SDavid Updegraff		rfc-2090; for example to work with atftp.  Lets lots of targets
168611ccc33fSMarcel Ziswiler		tftp down the same boot image concurrently.  Note: the Ethernet
168753a5c424SDavid Updegraff		driver in use must provide a function: mcast() to join/leave a
168853a5c424SDavid Updegraff		multicast group.
168953a5c424SDavid Updegraff
1690c609719bSwdenk- BOOTP Recovery Mode:
1691c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY
1692c609719bSwdenk
1693c609719bSwdenk		If you have many targets in a network that try to
1694c609719bSwdenk		boot using BOOTP, you may want to avoid that all
1695c609719bSwdenk		systems send out BOOTP requests at precisely the same
1696c609719bSwdenk		moment (which would happen for instance at recovery
1697c609719bSwdenk		from a power failure, when all systems will try to
1698c609719bSwdenk		boot, thus flooding the BOOTP server. Defining
1699c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1700c609719bSwdenk		inserted before sending out BOOTP requests. The
17016c33c785SWolfgang Denk		following delays are inserted then:
1702c609719bSwdenk
1703c609719bSwdenk		1st BOOTP request:	delay 0 ... 1 sec
1704c609719bSwdenk		2nd BOOTP request:	delay 0 ... 2 sec
1705c609719bSwdenk		3rd BOOTP request:	delay 0 ... 4 sec
1706c609719bSwdenk		4th and following
1707c609719bSwdenk		BOOTP requests:		delay 0 ... 8 sec
1708c609719bSwdenk
1709fe389a82Sstroese- DHCP Advanced Options:
17101fe80d79SJon Loeliger		You can fine tune the DHCP functionality by defining
17111fe80d79SJon Loeliger		CONFIG_BOOTP_* symbols:
1712fe389a82Sstroese
17131fe80d79SJon Loeliger		CONFIG_BOOTP_SUBNETMASK
17141fe80d79SJon Loeliger		CONFIG_BOOTP_GATEWAY
17151fe80d79SJon Loeliger		CONFIG_BOOTP_HOSTNAME
17161fe80d79SJon Loeliger		CONFIG_BOOTP_NISDOMAIN
17171fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTPATH
17181fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTFILESIZE
17191fe80d79SJon Loeliger		CONFIG_BOOTP_DNS
17201fe80d79SJon Loeliger		CONFIG_BOOTP_DNS2
17211fe80d79SJon Loeliger		CONFIG_BOOTP_SEND_HOSTNAME
17221fe80d79SJon Loeliger		CONFIG_BOOTP_NTPSERVER
17231fe80d79SJon Loeliger		CONFIG_BOOTP_TIMEOFFSET
17241fe80d79SJon Loeliger		CONFIG_BOOTP_VENDOREX
17252c00e099SJoe Hershberger		CONFIG_BOOTP_MAY_FAIL
1726fe389a82Sstroese
17275d110f0aSWilson Callan		CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
17285d110f0aSWilson Callan		environment variable, not the BOOTP server.
1729fe389a82Sstroese
17302c00e099SJoe Hershberger		CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
17312c00e099SJoe Hershberger		after the configured retry count, the call will fail
17322c00e099SJoe Hershberger		instead of starting over.  This can be used to fail over
17332c00e099SJoe Hershberger		to Link-local IP address configuration if the DHCP server
17342c00e099SJoe Hershberger		is not available.
17352c00e099SJoe Hershberger
1736fe389a82Sstroese		CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1737fe389a82Sstroese		serverip from a DHCP server, it is possible that more
1738fe389a82Sstroese		than one DNS serverip is offered to the client.
1739fe389a82Sstroese		If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1740fe389a82Sstroese		serverip will be stored in the additional environment
1741fe389a82Sstroese		variable "dnsip2". The first DNS serverip is always
1742fe389a82Sstroese		stored in the variable "dnsip", when CONFIG_BOOTP_DNS
17431fe80d79SJon Loeliger		is defined.
1744fe389a82Sstroese
1745fe389a82Sstroese		CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1746fe389a82Sstroese		to do a dynamic update of a DNS server. To do this, they
1747fe389a82Sstroese		need the hostname of the DHCP requester.
17485d110f0aSWilson Callan		If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
17491fe80d79SJon Loeliger		of the "hostname" environment variable is passed as
17501fe80d79SJon Loeliger		option 12 to the DHCP server.
1751fe389a82Sstroese
1752d9a2f416SAras Vaichas		CONFIG_BOOTP_DHCP_REQUEST_DELAY
1753d9a2f416SAras Vaichas
1754d9a2f416SAras Vaichas		A 32bit value in microseconds for a delay between
1755d9a2f416SAras Vaichas		receiving a "DHCP Offer" and sending the "DHCP Request".
1756d9a2f416SAras Vaichas		This fixes a problem with certain DHCP servers that don't
1757d9a2f416SAras Vaichas		respond 100% of the time to a "DHCP request". E.g. On an
1758d9a2f416SAras Vaichas		AT91RM9200 processor running at 180MHz, this delay needed
1759d9a2f416SAras Vaichas		to be *at least* 15,000 usec before a Windows Server 2003
1760d9a2f416SAras Vaichas		DHCP server would reply 100% of the time. I recommend at
1761d9a2f416SAras Vaichas		least 50,000 usec to be safe. The alternative is to hope
1762d9a2f416SAras Vaichas		that one of the retries will be successful but note that
1763d9a2f416SAras Vaichas		the DHCP timeout and retry process takes a longer than
1764d9a2f416SAras Vaichas		this delay.
1765d9a2f416SAras Vaichas
1766d22c338eSJoe Hershberger - Link-local IP address negotiation:
1767d22c338eSJoe Hershberger		Negotiate with other link-local clients on the local network
1768d22c338eSJoe Hershberger		for an address that doesn't require explicit configuration.
1769d22c338eSJoe Hershberger		This is especially useful if a DHCP server cannot be guaranteed
1770d22c338eSJoe Hershberger		to exist in all environments that the device must operate.
1771d22c338eSJoe Hershberger
1772d22c338eSJoe Hershberger		See doc/README.link-local for more information.
1773d22c338eSJoe Hershberger
1774a3d991bdSwdenk - CDP Options:
1775a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID
1776a3d991bdSwdenk
1777a3d991bdSwdenk		The device id used in CDP trigger frames.
1778a3d991bdSwdenk
1779a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID_PREFIX
1780a3d991bdSwdenk
1781a3d991bdSwdenk		A two character string which is prefixed to the MAC address
1782a3d991bdSwdenk		of the device.
1783a3d991bdSwdenk
1784a3d991bdSwdenk		CONFIG_CDP_PORT_ID
1785a3d991bdSwdenk
1786a3d991bdSwdenk		A printf format string which contains the ascii name of
1787a3d991bdSwdenk		the port. Normally is set to "eth%d" which sets
178811ccc33fSMarcel Ziswiler		eth0 for the first Ethernet, eth1 for the second etc.
1789a3d991bdSwdenk
1790a3d991bdSwdenk		CONFIG_CDP_CAPABILITIES
1791a3d991bdSwdenk
1792a3d991bdSwdenk		A 32bit integer which indicates the device capabilities;
1793a3d991bdSwdenk		0x00000010 for a normal host which does not forwards.
1794a3d991bdSwdenk
1795a3d991bdSwdenk		CONFIG_CDP_VERSION
1796a3d991bdSwdenk
1797a3d991bdSwdenk		An ascii string containing the version of the software.
1798a3d991bdSwdenk
1799a3d991bdSwdenk		CONFIG_CDP_PLATFORM
1800a3d991bdSwdenk
1801a3d991bdSwdenk		An ascii string containing the name of the platform.
1802a3d991bdSwdenk
1803a3d991bdSwdenk		CONFIG_CDP_TRIGGER
1804a3d991bdSwdenk
1805a3d991bdSwdenk		A 32bit integer sent on the trigger.
1806a3d991bdSwdenk
1807a3d991bdSwdenk		CONFIG_CDP_POWER_CONSUMPTION
1808a3d991bdSwdenk
1809a3d991bdSwdenk		A 16bit integer containing the power consumption of the
1810a3d991bdSwdenk		device in .1 of milliwatts.
1811a3d991bdSwdenk
1812a3d991bdSwdenk		CONFIG_CDP_APPLIANCE_VLAN_TYPE
1813a3d991bdSwdenk
1814a3d991bdSwdenk		A byte containing the id of the VLAN.
1815a3d991bdSwdenk
1816c609719bSwdenk- Status LED:	CONFIG_STATUS_LED
1817c609719bSwdenk
1818c609719bSwdenk		Several configurations allow to display the current
1819c609719bSwdenk		status using a LED. For instance, the LED will blink
1820c609719bSwdenk		fast while running U-Boot code, stop blinking as
1821c609719bSwdenk		soon as a reply to a BOOTP request was received, and
1822c609719bSwdenk		start blinking slow once the Linux kernel is running
1823c609719bSwdenk		(supported by a status LED driver in the Linux
1824c609719bSwdenk		kernel). Defining CONFIG_STATUS_LED enables this
1825c609719bSwdenk		feature in U-Boot.
1826c609719bSwdenk
1827c609719bSwdenk- CAN Support:	CONFIG_CAN_DRIVER
1828c609719bSwdenk
1829c609719bSwdenk		Defining CONFIG_CAN_DRIVER enables CAN driver support
1830c609719bSwdenk		on those systems that support this (optional)
1831c609719bSwdenk		feature, like the TQM8xxL modules.
1832c609719bSwdenk
1833c609719bSwdenk- I2C Support:	CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1834c609719bSwdenk
1835b37c7e5eSwdenk		These enable I2C serial bus commands. Defining either of
1836b37c7e5eSwdenk		(but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
183711ccc33fSMarcel Ziswiler		include the appropriate I2C driver for the selected CPU.
1838c609719bSwdenk
1839b37c7e5eSwdenk		This will allow you to use i2c commands at the u-boot
1840602ad3b3SJon Loeliger		command line (as long as you set CONFIG_CMD_I2C in
1841b37c7e5eSwdenk		CONFIG_COMMANDS) and communicate with i2c based realtime
1842b37c7e5eSwdenk		clock chips. See common/cmd_i2c.c for a description of the
1843c609719bSwdenk		command line interface.
1844c609719bSwdenk
1845bb99ad6dSBen Warren		CONFIG_HARD_I2C selects a hardware I2C controller.
1846c609719bSwdenk
1847b37c7e5eSwdenk		CONFIG_SOFT_I2C configures u-boot to use a software (aka
1848b37c7e5eSwdenk		bit-banging) driver instead of CPM or similar hardware
1849b37c7e5eSwdenk		support for I2C.
1850c609719bSwdenk
1851b37c7e5eSwdenk		There are several other quantities that must also be
1852b37c7e5eSwdenk		defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1853c609719bSwdenk
18546d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		In both cases you will need to define CONFIG_SYS_I2C_SPEED
1855b37c7e5eSwdenk		to be the frequency (in Hz) at which you wish your i2c bus
18566d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
185711ccc33fSMarcel Ziswiler		the CPU's i2c node address).
1858c609719bSwdenk
18598d321b81SPeter Tyser		Now, the u-boot i2c code for the mpc8xx
1860a47a12beSStefan Roese		(arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
18618d321b81SPeter Tyser		and so its address should therefore be cleared to 0 (See,
18628d321b81SPeter Tyser		eg, MPC823e User's Manual p.16-473). So, set
18638d321b81SPeter Tyser		CONFIG_SYS_I2C_SLAVE to 0.
1864b37c7e5eSwdenk
18655da71efaSEric Millbrandt		CONFIG_SYS_I2C_INIT_MPC5XXX
18665da71efaSEric Millbrandt
18675da71efaSEric Millbrandt		When a board is reset during an i2c bus transfer
18685da71efaSEric Millbrandt		chips might think that the current transfer is still
18695da71efaSEric Millbrandt		in progress.  Reset the slave devices by sending start
18705da71efaSEric Millbrandt		commands until the slave device responds.
18715da71efaSEric Millbrandt
1872b37c7e5eSwdenk		That's all that's required for CONFIG_HARD_I2C.
1873b37c7e5eSwdenk
1874b37c7e5eSwdenk		If you use the software i2c interface (CONFIG_SOFT_I2C)
1875b37c7e5eSwdenk		then the following macros need to be defined (examples are
1876b37c7e5eSwdenk		from include/configs/lwmon.h):
1877c609719bSwdenk
1878c609719bSwdenk		I2C_INIT
1879c609719bSwdenk
1880b37c7e5eSwdenk		(Optional). Any commands necessary to enable the I2C
1881c609719bSwdenk		controller or configure ports.
1882c609719bSwdenk
1883b37c7e5eSwdenk		eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |=	PB_SCL)
1884b37c7e5eSwdenk
1885c609719bSwdenk		I2C_PORT
1886c609719bSwdenk
1887c609719bSwdenk		(Only for MPC8260 CPU). The I/O port to use (the code
1888c609719bSwdenk		assumes both bits are on the same port). Valid values
1889c609719bSwdenk		are 0..3 for ports A..D.
1890c609719bSwdenk
1891c609719bSwdenk		I2C_ACTIVE
1892c609719bSwdenk
1893c609719bSwdenk		The code necessary to make the I2C data line active
1894c609719bSwdenk		(driven).  If the data line is open collector, this
1895c609719bSwdenk		define can be null.
1896c609719bSwdenk
1897b37c7e5eSwdenk		eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |=  PB_SDA)
1898b37c7e5eSwdenk
1899c609719bSwdenk		I2C_TRISTATE
1900c609719bSwdenk
1901c609719bSwdenk		The code necessary to make the I2C data line tri-stated
1902c609719bSwdenk		(inactive).  If the data line is open collector, this
1903c609719bSwdenk		define can be null.
1904c609719bSwdenk
1905b37c7e5eSwdenk		eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1906b37c7e5eSwdenk
1907c609719bSwdenk		I2C_READ
1908c609719bSwdenk
1909c609719bSwdenk		Code that returns TRUE if the I2C data line is high,
1910c609719bSwdenk		FALSE if it is low.
1911c609719bSwdenk
1912b37c7e5eSwdenk		eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1913b37c7e5eSwdenk
1914c609719bSwdenk		I2C_SDA(bit)
1915c609719bSwdenk
1916c609719bSwdenk		If <bit> is TRUE, sets the I2C data line high. If it
1917c609719bSwdenk		is FALSE, it clears it (low).
1918c609719bSwdenk
1919b37c7e5eSwdenk		eg: #define I2C_SDA(bit) \
1920b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SDA; \
1921b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SDA
1922b37c7e5eSwdenk
1923c609719bSwdenk		I2C_SCL(bit)
1924c609719bSwdenk
1925c609719bSwdenk		If <bit> is TRUE, sets the I2C clock line high. If it
1926c609719bSwdenk		is FALSE, it clears it (low).
1927c609719bSwdenk
1928b37c7e5eSwdenk		eg: #define I2C_SCL(bit) \
1929b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SCL; \
1930b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SCL
1931b37c7e5eSwdenk
1932c609719bSwdenk		I2C_DELAY
1933c609719bSwdenk
1934c609719bSwdenk		This delay is invoked four times per clock cycle so this
1935c609719bSwdenk		controls the rate of data transfer.  The data rate thus
1936b37c7e5eSwdenk		is 1 / (I2C_DELAY * 4). Often defined to be something
1937b37c7e5eSwdenk		like:
1938b37c7e5eSwdenk
1939b37c7e5eSwdenk		#define I2C_DELAY  udelay(2)
1940c609719bSwdenk
1941793b5726SMike Frysinger		CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1942793b5726SMike Frysinger
1943793b5726SMike Frysinger		If your arch supports the generic GPIO framework (asm/gpio.h),
1944793b5726SMike Frysinger		then you may alternatively define the two GPIOs that are to be
1945793b5726SMike Frysinger		used as SCL / SDA.  Any of the previous I2C_xxx macros will
1946793b5726SMike Frysinger		have GPIO-based defaults assigned to them as appropriate.
1947793b5726SMike Frysinger
1948793b5726SMike Frysinger		You should define these to the GPIO value as given directly to
1949793b5726SMike Frysinger		the generic GPIO functions.
1950793b5726SMike Frysinger
19516d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_I2C_INIT_BOARD
195247cd00faSwdenk
195347cd00faSwdenk		When a board is reset during an i2c bus transfer
195447cd00faSwdenk		chips might think that the current transfer is still
195547cd00faSwdenk		in progress. On some boards it is possible to access
195647cd00faSwdenk		the i2c SCLK line directly, either by using the
195747cd00faSwdenk		processor pin as a GPIO or by having a second pin
195847cd00faSwdenk		connected to the bus. If this option is defined a
195947cd00faSwdenk		custom i2c_init_board() routine in boards/xxx/board.c
196047cd00faSwdenk		is run early in the boot sequence.
196147cd00faSwdenk
196226a33504SRichard Retanubun		CONFIG_SYS_I2C_BOARD_LATE_INIT
196326a33504SRichard Retanubun
196426a33504SRichard Retanubun		An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
196526a33504SRichard Retanubun		defined a custom i2c_board_late_init() routine in
196626a33504SRichard Retanubun		boards/xxx/board.c is run AFTER the operations in i2c_init()
196726a33504SRichard Retanubun		is completed. This callpoint can be used to unreset i2c bus
196826a33504SRichard Retanubun		using CPU i2c controller register accesses for CPUs whose i2c
196926a33504SRichard Retanubun		controller provide such a method. It is called at the end of
197026a33504SRichard Retanubun		i2c_init() to allow i2c_init operations to setup the i2c bus
197126a33504SRichard Retanubun		controller on the CPU (e.g. setting bus speed & slave address).
197226a33504SRichard Retanubun
197317ea1177Swdenk		CONFIG_I2CFAST (PPC405GP|PPC405EP only)
197417ea1177Swdenk
197517ea1177Swdenk		This option enables configuration of bi_iic_fast[] flags
197617ea1177Swdenk		in u-boot bd_info structure based on u-boot environment
197717ea1177Swdenk		variable "i2cfast". (see also i2cfast)
197817ea1177Swdenk
1979bb99ad6dSBen Warren		CONFIG_I2C_MULTI_BUS
1980bb99ad6dSBen Warren
1981bb99ad6dSBen Warren		This option allows the use of multiple I2C buses, each of which
1982bb99ad6dSBen Warren		must have a controller.	 At any point in time, only one bus is
1983bb99ad6dSBen Warren		active.	 To switch to a different bus, use the 'i2c dev' command.
1984bb99ad6dSBen Warren		Note that bus numbering is zero-based.
1985bb99ad6dSBen Warren
19866d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_I2C_NOPROBES
1987bb99ad6dSBen Warren
1988bb99ad6dSBen Warren		This option specifies a list of I2C devices that will be skipped
19890f89c54bSPeter Tyser		when the 'i2c probe' command is issued.	 If CONFIG_I2C_MULTI_BUS
19900f89c54bSPeter Tyser		is set, specify a list of bus-device pairs.  Otherwise, specify
19910f89c54bSPeter Tyser		a 1D array of device addresses
1992bb99ad6dSBen Warren
1993bb99ad6dSBen Warren		e.g.
1994bb99ad6dSBen Warren			#undef	CONFIG_I2C_MULTI_BUS
19956d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			#define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1996bb99ad6dSBen Warren
1997bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on a board with one I2C bus
1998bb99ad6dSBen Warren
1999bb99ad6dSBen Warren			#define CONFIG_I2C_MULTI_BUS
20006d0f6bcfSJean-Christophe PLAGNIOL-VILLARD			#define CONFIG_SYS_I2C_MULTI_NOPROBES	{{0,0x50},{0,0x68},{1,0x54}}
2001bb99ad6dSBen Warren
2002bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2003bb99ad6dSBen Warren
20046d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SPD_BUS_NUM
2005be5e6181STimur Tabi
2006be5e6181STimur Tabi		If defined, then this indicates the I2C bus number for DDR SPD.
2007be5e6181STimur Tabi		If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2008be5e6181STimur Tabi
20096d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_RTC_BUS_NUM
20100dc018ecSStefan Roese
20110dc018ecSStefan Roese		If defined, then this indicates the I2C bus number for the RTC.
20120dc018ecSStefan Roese		If not defined, then U-Boot assumes that RTC is on I2C bus 0.
20130dc018ecSStefan Roese
20146d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_DTT_BUS_NUM
20150dc018ecSStefan Roese
20160dc018ecSStefan Roese		If defined, then this indicates the I2C bus number for the DTT.
20170dc018ecSStefan Roese		If not defined, then U-Boot assumes that DTT is on I2C bus 0.
20180dc018ecSStefan Roese
20196d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_I2C_DTT_ADDR:
20209ebbb54fSVictor Gallardo
20219ebbb54fSVictor Gallardo		If defined, specifies the I2C address of the DTT device.
20229ebbb54fSVictor Gallardo		If not defined, then U-Boot uses predefined value for
20239ebbb54fSVictor Gallardo		specified DTT device.
20249ebbb54fSVictor Gallardo
2025be5e6181STimur Tabi		CONFIG_FSL_I2C
2026be5e6181STimur Tabi
2027be5e6181STimur Tabi		Define this option if you want to use Freescale's I2C driver in
20287817cb20SMarcel Ziswiler		drivers/i2c/fsl_i2c.c.
2029be5e6181STimur Tabi
203067b23a32SHeiko Schocher		CONFIG_I2C_MUX
203167b23a32SHeiko Schocher
203267b23a32SHeiko Schocher		Define this option if you have I2C devices reached over 1 .. n
203367b23a32SHeiko Schocher		I2C Muxes like the pca9544a. This option addes a new I2C
203467b23a32SHeiko Schocher		Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
203567b23a32SHeiko Schocher		new I2C Bus to the existing I2C Busses. If you select the
203667b23a32SHeiko Schocher		new Bus with "i2c dev", u-bbot sends first the commandos for
203767b23a32SHeiko Schocher		the muxes to activate this new "bus".
203867b23a32SHeiko Schocher
203967b23a32SHeiko Schocher		CONFIG_I2C_MULTI_BUS must be also defined, to use this
204067b23a32SHeiko Schocher		feature!
204167b23a32SHeiko Schocher
204267b23a32SHeiko Schocher		Example:
204367b23a32SHeiko Schocher		Adding a new I2C Bus reached over 2 pca9544a muxes
204467b23a32SHeiko Schocher			The First mux with address 70 and channel 6
204567b23a32SHeiko Schocher			The Second mux with address 71 and channel 4
204667b23a32SHeiko Schocher
204767b23a32SHeiko Schocher		=> i2c bus pca9544a:70:6:pca9544a:71:4
204867b23a32SHeiko Schocher
204967b23a32SHeiko Schocher		Use the "i2c bus" command without parameter, to get a list
205067b23a32SHeiko Schocher		of I2C Busses with muxes:
205167b23a32SHeiko Schocher
205267b23a32SHeiko Schocher		=> i2c bus
205367b23a32SHeiko Schocher		Busses reached over muxes:
205467b23a32SHeiko Schocher		Bus ID: 2
205567b23a32SHeiko Schocher		  reached over Mux(es):
205667b23a32SHeiko Schocher		    pca9544a@70 ch: 4
205767b23a32SHeiko Schocher		Bus ID: 3
205867b23a32SHeiko Schocher		  reached over Mux(es):
205967b23a32SHeiko Schocher		    pca9544a@70 ch: 6
206067b23a32SHeiko Schocher		    pca9544a@71 ch: 4
206167b23a32SHeiko Schocher		=>
206267b23a32SHeiko Schocher
206367b23a32SHeiko Schocher		If you now switch to the new I2C Bus 3 with "i2c dev 3"
2064f9a78b8dSMichael Jones		u-boot first sends the command to the mux@70 to enable
2065f9a78b8dSMichael Jones		channel 6, and then the command to the mux@71 to enable
206667b23a32SHeiko Schocher		the channel 4.
206767b23a32SHeiko Schocher
206867b23a32SHeiko Schocher		After that, you can use the "normal" i2c commands as
2069f9a78b8dSMichael Jones		usual to communicate with your I2C devices behind
207067b23a32SHeiko Schocher		the 2 muxes.
207167b23a32SHeiko Schocher
207267b23a32SHeiko Schocher		This option is actually implemented for the bitbanging
207367b23a32SHeiko Schocher		algorithm in common/soft_i2c.c and for the Hardware I2C
207467b23a32SHeiko Schocher		Bus on the MPC8260. But it should be not so difficult
207567b23a32SHeiko Schocher		to add this option to other architectures.
207667b23a32SHeiko Schocher
20772ac6985aSAndrew Dyer		CONFIG_SOFT_I2C_READ_REPEATED_START
20782ac6985aSAndrew Dyer
20792ac6985aSAndrew Dyer		defining this will force the i2c_read() function in
20802ac6985aSAndrew Dyer		the soft_i2c driver to perform an I2C repeated start
20812ac6985aSAndrew Dyer		between writing the address pointer and reading the
20822ac6985aSAndrew Dyer		data.  If this define is omitted the default behaviour
20832ac6985aSAndrew Dyer		of doing a stop-start sequence will be used.  Most I2C
20842ac6985aSAndrew Dyer		devices can use either method, but some require one or
20852ac6985aSAndrew Dyer		the other.
2086be5e6181STimur Tabi
2087c609719bSwdenk- SPI Support:	CONFIG_SPI
2088c609719bSwdenk
2089c609719bSwdenk		Enables SPI driver (so far only tested with
2090c609719bSwdenk		SPI EEPROM, also an instance works with Crystal A/D and
2091c609719bSwdenk		D/As on the SACSng board)
2092c609719bSwdenk
20936639562eSYoshihiro Shimoda		CONFIG_SH_SPI
20946639562eSYoshihiro Shimoda
20956639562eSYoshihiro Shimoda		Enables the driver for SPI controller on SuperH. Currently
20966639562eSYoshihiro Shimoda		only SH7757 is supported.
20976639562eSYoshihiro Shimoda
2098c609719bSwdenk		CONFIG_SPI_X
2099c609719bSwdenk
2100c609719bSwdenk		Enables extended (16-bit) SPI EEPROM addressing.
2101c609719bSwdenk		(symmetrical to CONFIG_I2C_X)
2102c609719bSwdenk
2103c609719bSwdenk		CONFIG_SOFT_SPI
2104c609719bSwdenk
2105c609719bSwdenk		Enables a software (bit-bang) SPI driver rather than
2106c609719bSwdenk		using hardware support. This is a general purpose
2107c609719bSwdenk		driver that only requires three general I/O port pins
2108c609719bSwdenk		(two outputs, one input) to function. If this is
2109c609719bSwdenk		defined, the board configuration must define several
2110c609719bSwdenk		SPI configuration items (port pins to use, etc). For
2111c609719bSwdenk		an example, see include/configs/sacsng.h.
2112c609719bSwdenk
211304a9e118SBen Warren		CONFIG_HARD_SPI
211404a9e118SBen Warren
211504a9e118SBen Warren		Enables a hardware SPI driver for general-purpose reads
211604a9e118SBen Warren		and writes.  As with CONFIG_SOFT_SPI, the board configuration
211704a9e118SBen Warren		must define a list of chip-select function pointers.
211804a9e118SBen Warren		Currently supported on some MPC8xxx processors.	 For an
211904a9e118SBen Warren		example, see include/configs/mpc8349emds.h.
212004a9e118SBen Warren
212138254f45SGuennadi Liakhovetski		CONFIG_MXC_SPI
212238254f45SGuennadi Liakhovetski
212338254f45SGuennadi Liakhovetski		Enables the driver for the SPI controllers on i.MX and MXC
21242e3cd1cdSFabio Estevam		SoCs. Currently i.MX31/35/51 are supported.
212538254f45SGuennadi Liakhovetski
21260133502eSMatthias Fuchs- FPGA Support: CONFIG_FPGA
21270133502eSMatthias Fuchs
21280133502eSMatthias Fuchs		Enables FPGA subsystem.
21290133502eSMatthias Fuchs
21300133502eSMatthias Fuchs		CONFIG_FPGA_<vendor>
21310133502eSMatthias Fuchs
21320133502eSMatthias Fuchs		Enables support for specific chip vendors.
21330133502eSMatthias Fuchs		(ALTERA, XILINX)
21340133502eSMatthias Fuchs
21350133502eSMatthias Fuchs		CONFIG_FPGA_<family>
21360133502eSMatthias Fuchs
21370133502eSMatthias Fuchs		Enables support for FPGA family.
21380133502eSMatthias Fuchs		(SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
21390133502eSMatthias Fuchs
21400133502eSMatthias Fuchs		CONFIG_FPGA_COUNT
2141c609719bSwdenk
2142c609719bSwdenk		Specify the number of FPGA devices to support.
2143c609719bSwdenk
21446d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_PROG_FEEDBACK
2145c609719bSwdenk
2146c609719bSwdenk		Enable printing of hash marks during FPGA configuration.
2147c609719bSwdenk
21486d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_BUSY
2149c609719bSwdenk
2150c609719bSwdenk		Enable checks on FPGA configuration interface busy
2151c609719bSwdenk		status by the configuration function. This option
2152c609719bSwdenk		will require a board or device specific function to
2153c609719bSwdenk		be written.
2154c609719bSwdenk
2155c609719bSwdenk		CONFIG_FPGA_DELAY
2156c609719bSwdenk
2157c609719bSwdenk		If defined, a function that provides delays in the FPGA
2158c609719bSwdenk		configuration driver.
2159c609719bSwdenk
21606d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_CTRLC
2161c609719bSwdenk		Allow Control-C to interrupt FPGA configuration
2162c609719bSwdenk
21636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_CHECK_ERROR
2164c609719bSwdenk
2165c609719bSwdenk		Check for configuration errors during FPGA bitfile
2166c609719bSwdenk		loading. For example, abort during Virtex II
2167c609719bSwdenk		configuration if the INIT_B line goes low (which
2168c609719bSwdenk		indicated a CRC error).
2169c609719bSwdenk
21706d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_INIT
2171c609719bSwdenk
2172c609719bSwdenk		Maximum time to wait for the INIT_B line to deassert
2173c609719bSwdenk		after PROB_B has been deasserted during a Virtex II
2174c609719bSwdenk		FPGA configuration sequence. The default time is 500
217511ccc33fSMarcel Ziswiler		ms.
2176c609719bSwdenk
21776d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_BUSY
2178c609719bSwdenk
2179c609719bSwdenk		Maximum time to wait for BUSY to deassert during
218011ccc33fSMarcel Ziswiler		Virtex II FPGA configuration. The default is 5 ms.
2181c609719bSwdenk
21826d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FPGA_WAIT_CONFIG
2183c609719bSwdenk
2184c609719bSwdenk		Time to wait after FPGA configuration. The default is
218511ccc33fSMarcel Ziswiler		200 ms.
2186c609719bSwdenk
2187c609719bSwdenk- Configuration Management:
2188c609719bSwdenk		CONFIG_IDENT_STRING
2189c609719bSwdenk
2190c609719bSwdenk		If defined, this string will be added to the U-Boot
2191c609719bSwdenk		version information (U_BOOT_VERSION)
2192c609719bSwdenk
2193c609719bSwdenk- Vendor Parameter Protection:
2194c609719bSwdenk
2195c609719bSwdenk		U-Boot considers the values of the environment
2196c609719bSwdenk		variables "serial#" (Board Serial Number) and
21977152b1d0Swdenk		"ethaddr" (Ethernet Address) to be parameters that
2198c609719bSwdenk		are set once by the board vendor / manufacturer, and
2199c609719bSwdenk		protects these variables from casual modification by
2200c609719bSwdenk		the user. Once set, these variables are read-only,
2201c609719bSwdenk		and write or delete attempts are rejected. You can
220211ccc33fSMarcel Ziswiler		change this behaviour:
2203c609719bSwdenk
2204c609719bSwdenk		If CONFIG_ENV_OVERWRITE is #defined in your config
2205c609719bSwdenk		file, the write protection for vendor parameters is
220647cd00faSwdenk		completely disabled. Anybody can change or delete
2207c609719bSwdenk		these parameters.
2208c609719bSwdenk
2209c609719bSwdenk		Alternatively, if you #define _both_ CONFIG_ETHADDR
2210c609719bSwdenk		_and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
221111ccc33fSMarcel Ziswiler		Ethernet address is installed in the environment,
2212c609719bSwdenk		which can be changed exactly ONCE by the user. [The
2213c609719bSwdenk		serial# is unaffected by this, i. e. it remains
2214c609719bSwdenk		read-only.]
2215c609719bSwdenk
22162598090bSJoe Hershberger		The same can be accomplished in a more flexible way
22172598090bSJoe Hershberger		for any variable by configuring the type of access
22182598090bSJoe Hershberger		to allow for those variables in the ".flags" variable
22192598090bSJoe Hershberger		or define CONFIG_ENV_FLAGS_LIST_STATIC.
22202598090bSJoe Hershberger
2221c609719bSwdenk- Protected RAM:
2222c609719bSwdenk		CONFIG_PRAM
2223c609719bSwdenk
2224c609719bSwdenk		Define this variable to enable the reservation of
2225c609719bSwdenk		"protected RAM", i. e. RAM which is not overwritten
2226c609719bSwdenk		by U-Boot. Define CONFIG_PRAM to hold the number of
2227c609719bSwdenk		kB you want to reserve for pRAM. You can overwrite
2228c609719bSwdenk		this default value by defining an environment
2229c609719bSwdenk		variable "pram" to the number of kB you want to
2230c609719bSwdenk		reserve. Note that the board info structure will
2231c609719bSwdenk		still show the full amount of RAM. If pRAM is
2232c609719bSwdenk		reserved, a new environment variable "mem" will
2233c609719bSwdenk		automatically be defined to hold the amount of
2234c609719bSwdenk		remaining RAM in a form that can be passed as boot
2235c609719bSwdenk		argument to Linux, for instance like that:
2236c609719bSwdenk
2237fe126d8bSWolfgang Denk			setenv bootargs ... mem=\${mem}
2238c609719bSwdenk			saveenv
2239c609719bSwdenk
2240c609719bSwdenk		This way you can tell Linux not to use this memory,
2241c609719bSwdenk		either, which results in a memory region that will
2242c609719bSwdenk		not be affected by reboots.
2243c609719bSwdenk
2244c609719bSwdenk		*WARNING* If your board configuration uses automatic
2245c609719bSwdenk		detection of the RAM size, you must make sure that
2246c609719bSwdenk		this memory test is non-destructive. So far, the
2247c609719bSwdenk		following board configurations are known to be
2248c609719bSwdenk		"pRAM-clean":
2249c609719bSwdenk
22501b0757ecSWolfgang Denk			IVMS8, IVML24, SPD8xx, TQM8xxL,
22511b0757ecSWolfgang Denk			HERMES, IP860, RPXlite, LWMON,
2252544d97e9SWolfgang Denk			FLAGADM, TQM8260
2253c609719bSwdenk
225440fef049SGabe Black- Access to physical memory region (> 4GB)
225540fef049SGabe Black		Some basic support is provided for operations on memory not
225640fef049SGabe Black		normally accessible to U-Boot - e.g. some architectures
225740fef049SGabe Black		support access to more than 4GB of memory on 32-bit
225840fef049SGabe Black		machines using physical address extension or similar.
225940fef049SGabe Black		Define CONFIG_PHYSMEM to access this basic support, which
226040fef049SGabe Black		currently only supports clearing the memory.
226140fef049SGabe Black
2262c609719bSwdenk- Error Recovery:
2263c609719bSwdenk		CONFIG_PANIC_HANG
2264c609719bSwdenk
2265c609719bSwdenk		Define this variable to stop the system in case of a
2266c609719bSwdenk		fatal error, so that you have to reset it manually.
2267c609719bSwdenk		This is probably NOT a good idea for an embedded
226811ccc33fSMarcel Ziswiler		system where you want the system to reboot
2269c609719bSwdenk		automatically as fast as possible, but it may be
2270c609719bSwdenk		useful during development since you can try to debug
2271c609719bSwdenk		the conditions that lead to the situation.
2272c609719bSwdenk
2273c609719bSwdenk		CONFIG_NET_RETRY_COUNT
2274c609719bSwdenk
2275c609719bSwdenk		This variable defines the number of retries for
2276c609719bSwdenk		network operations like ARP, RARP, TFTP, or BOOTP
2277c609719bSwdenk		before giving up the operation. If not defined, a
2278c609719bSwdenk		default value of 5 is used.
2279c609719bSwdenk
228040cb90eeSGuennadi Liakhovetski		CONFIG_ARP_TIMEOUT
228140cb90eeSGuennadi Liakhovetski
228240cb90eeSGuennadi Liakhovetski		Timeout waiting for an ARP reply in milliseconds.
228340cb90eeSGuennadi Liakhovetski
228448a3e999STetsuyuki Kobayashi		CONFIG_NFS_TIMEOUT
228548a3e999STetsuyuki Kobayashi
228648a3e999STetsuyuki Kobayashi		Timeout in milliseconds used in NFS protocol.
228748a3e999STetsuyuki Kobayashi		If you encounter "ERROR: Cannot umount" in nfs command,
228848a3e999STetsuyuki Kobayashi		try longer timeout such as
228948a3e999STetsuyuki Kobayashi		#define CONFIG_NFS_TIMEOUT 10000UL
229048a3e999STetsuyuki Kobayashi
2291c609719bSwdenk- Command Interpreter:
22928078f1a5SWolfgang Denk		CONFIG_AUTO_COMPLETE
229304a85b3bSwdenk
229404a85b3bSwdenk		Enable auto completion of commands using TAB.
229504a85b3bSwdenk
22968078f1a5SWolfgang Denk		Note that this feature has NOT been implemented yet
22978078f1a5SWolfgang Denk		for the "hush" shell.
22988078f1a5SWolfgang Denk
22998078f1a5SWolfgang Denk
23006d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_HUSH_PARSER
2301c609719bSwdenk
2302c609719bSwdenk		Define this variable to enable the "hush" shell (from
2303c609719bSwdenk		Busybox) as command line interpreter, thus enabling
2304c609719bSwdenk		powerful command line syntax like
2305c609719bSwdenk		if...then...else...fi conditionals or `&&' and '||'
2306c609719bSwdenk		constructs ("shell scripts").
2307c609719bSwdenk
2308c609719bSwdenk		If undefined, you get the old, much simpler behaviour
2309c609719bSwdenk		with a somewhat smaller memory footprint.
2310c609719bSwdenk
2311c609719bSwdenk
23126d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_PROMPT_HUSH_PS2
2313c609719bSwdenk
2314c609719bSwdenk		This defines the secondary prompt string, which is
2315c609719bSwdenk		printed when the command interpreter needs more input
2316c609719bSwdenk		to complete a command. Usually "> ".
2317c609719bSwdenk
2318c609719bSwdenk	Note:
2319c609719bSwdenk
2320c609719bSwdenk		In the current implementation, the local variables
2321c609719bSwdenk		space and global environment variables space are
2322c609719bSwdenk		separated. Local variables are those you define by
23233b57fe0aSwdenk		simply typing `name=value'. To access a local
2324c609719bSwdenk		variable later on, you have write `$name' or
23253b57fe0aSwdenk		`${name}'; to execute the contents of a variable
23263b57fe0aSwdenk		directly type `$name' at the command prompt.
2327c609719bSwdenk
2328c609719bSwdenk		Global environment variables are those you use
2329c609719bSwdenk		setenv/printenv to work with. To run a command stored
2330c609719bSwdenk		in such a variable, you need to use the run command,
2331c609719bSwdenk		and you must not use the '$' sign to access them.
2332c609719bSwdenk
2333c609719bSwdenk		To store commands and special characters in a
2334c609719bSwdenk		variable, please use double quotation marks
2335c609719bSwdenk		surrounding the whole text of the variable, instead
2336c609719bSwdenk		of the backslashes before semicolons and special
2337c609719bSwdenk		symbols.
2338c609719bSwdenk
2339aa0c71acSWolfgang Denk- Commandline Editing and History:
2340aa0c71acSWolfgang Denk		CONFIG_CMDLINE_EDITING
2341aa0c71acSWolfgang Denk
234211ccc33fSMarcel Ziswiler		Enable editing and History functions for interactive
2343aa0c71acSWolfgang Denk		commandline input operations
2344aa0c71acSWolfgang Denk
2345a8c7c708Swdenk- Default Environment:
2346c609719bSwdenk		CONFIG_EXTRA_ENV_SETTINGS
2347c609719bSwdenk
2348c609719bSwdenk		Define this to contain any number of null terminated
2349c609719bSwdenk		strings (variable = value pairs) that will be part of
23507152b1d0Swdenk		the default environment compiled into the boot image.
23512262cfeeSwdenk
2352c609719bSwdenk		For example, place something like this in your
2353c609719bSwdenk		board's config file:
2354c609719bSwdenk
2355c609719bSwdenk		#define CONFIG_EXTRA_ENV_SETTINGS \
2356c609719bSwdenk			"myvar1=value1\0" \
2357c609719bSwdenk			"myvar2=value2\0"
2358c609719bSwdenk
2359c609719bSwdenk		Warning: This method is based on knowledge about the
2360c609719bSwdenk		internal format how the environment is stored by the
23612262cfeeSwdenk		U-Boot code. This is NOT an official, exported
2362c609719bSwdenk		interface! Although it is unlikely that this format
23637152b1d0Swdenk		will change soon, there is no guarantee either.
2364c609719bSwdenk		You better know what you are doing here.
2365c609719bSwdenk
2366c609719bSwdenk		Note: overly (ab)use of the default environment is
2367c609719bSwdenk		discouraged. Make sure to check other ways to preset
236874de7aefSWolfgang Denk		the environment like the "source" command or the
2369c609719bSwdenk		boot command first.
2370c609719bSwdenk
23715e724ca2SStephen Warren		CONFIG_ENV_VARS_UBOOT_CONFIG
23725e724ca2SStephen Warren
23735e724ca2SStephen Warren		Define this in order to add variables describing the
23745e724ca2SStephen Warren		U-Boot build configuration to the default environment.
23755e724ca2SStephen Warren		These will be named arch, cpu, board, vendor, and soc.
23765e724ca2SStephen Warren
23775e724ca2SStephen Warren		Enabling this option will cause the following to be defined:
23785e724ca2SStephen Warren
23795e724ca2SStephen Warren		- CONFIG_SYS_ARCH
23805e724ca2SStephen Warren		- CONFIG_SYS_CPU
23815e724ca2SStephen Warren		- CONFIG_SYS_BOARD
23825e724ca2SStephen Warren		- CONFIG_SYS_VENDOR
23835e724ca2SStephen Warren		- CONFIG_SYS_SOC
23845e724ca2SStephen Warren
23857e27f89fSTom Rini		CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
23867e27f89fSTom Rini
23877e27f89fSTom Rini		Define this in order to add variables describing certain
23887e27f89fSTom Rini		run-time determined information about the hardware to the
23897e27f89fSTom Rini		environment.  These will be named board_name, board_rev.
23907e27f89fSTom Rini
239106fd8538SSimon Glass		CONFIG_DELAY_ENVIRONMENT
239206fd8538SSimon Glass
239306fd8538SSimon Glass		Normally the environment is loaded when the board is
239406fd8538SSimon Glass		intialised so that it is available to U-Boot. This inhibits
239506fd8538SSimon Glass		that so that the environment is not available until
239606fd8538SSimon Glass		explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
239706fd8538SSimon Glass		this is instead controlled by the value of
239806fd8538SSimon Glass		/config/load-environment.
239906fd8538SSimon Glass
2400a8c7c708Swdenk- DataFlash Support:
24012abbe075Swdenk		CONFIG_HAS_DATAFLASH
24022abbe075Swdenk
24032abbe075Swdenk		Defining this option enables DataFlash features and
24042abbe075Swdenk		allows to read/write in Dataflash via the standard
24052abbe075Swdenk		commands cp, md...
24062abbe075Swdenk
2407f61ec45eSEric Nelson- Serial Flash support
2408f61ec45eSEric Nelson		CONFIG_CMD_SF
2409f61ec45eSEric Nelson
2410f61ec45eSEric Nelson		Defining this option enables SPI flash commands
2411f61ec45eSEric Nelson		'sf probe/read/write/erase/update'.
2412f61ec45eSEric Nelson
2413f61ec45eSEric Nelson		Usage requires an initial 'probe' to define the serial
2414f61ec45eSEric Nelson		flash parameters, followed by read/write/erase/update
2415f61ec45eSEric Nelson		commands.
2416f61ec45eSEric Nelson
2417f61ec45eSEric Nelson		The following defaults may be provided by the platform
2418f61ec45eSEric Nelson		to handle the common case when only a single serial
2419f61ec45eSEric Nelson		flash is present on the system.
2420f61ec45eSEric Nelson
2421f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_BUS		Bus identifier
2422f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_CS		Chip-select
2423f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_MODE 		(see include/spi.h)
2424f61ec45eSEric Nelson		CONFIG_SF_DEFAULT_SPEED		in Hz
2425f61ec45eSEric Nelson
242624007273SSimon Glass		CONFIG_CMD_SF_TEST
242724007273SSimon Glass
242824007273SSimon Glass		Define this option to include a destructive SPI flash
242924007273SSimon Glass		test ('sf test').
243024007273SSimon Glass
24313f85ce27Swdenk- SystemACE Support:
24323f85ce27Swdenk		CONFIG_SYSTEMACE
24333f85ce27Swdenk
24343f85ce27Swdenk		Adding this option adds support for Xilinx SystemACE
24353f85ce27Swdenk		chips attached via some sort of local bus. The address
243611ccc33fSMarcel Ziswiler		of the chip must also be defined in the
24376d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_SYSTEMACE_BASE macro. For example:
24383f85ce27Swdenk
24393f85ce27Swdenk		#define CONFIG_SYSTEMACE
24406d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		#define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
24413f85ce27Swdenk
24423f85ce27Swdenk		When SystemACE support is added, the "ace" device type
24433f85ce27Swdenk		becomes available to the fat commands, i.e. fatls.
24443f85ce27Swdenk
2445ecb0ccd9SWolfgang Denk- TFTP Fixed UDP Port:
2446ecb0ccd9SWolfgang Denk		CONFIG_TFTP_PORT
2447ecb0ccd9SWolfgang Denk
244828cb9375SWolfgang Denk		If this is defined, the environment variable tftpsrcp
2449ecb0ccd9SWolfgang Denk		is used to supply the TFTP UDP source port value.
245028cb9375SWolfgang Denk		If tftpsrcp isn't defined, the normal pseudo-random port
2451ecb0ccd9SWolfgang Denk		number generator is used.
2452ecb0ccd9SWolfgang Denk
245328cb9375SWolfgang Denk		Also, the environment variable tftpdstp is used to supply
245428cb9375SWolfgang Denk		the TFTP UDP destination port value.  If tftpdstp isn't
245528cb9375SWolfgang Denk		defined, the normal port 69 is used.
245628cb9375SWolfgang Denk
245728cb9375SWolfgang Denk		The purpose for tftpsrcp is to allow a TFTP server to
2458ecb0ccd9SWolfgang Denk		blindly start the TFTP transfer using the pre-configured
2459ecb0ccd9SWolfgang Denk		target IP address and UDP port. This has the effect of
2460ecb0ccd9SWolfgang Denk		"punching through" the (Windows XP) firewall, allowing
2461ecb0ccd9SWolfgang Denk		the remainder of the TFTP transfer to proceed normally.
2462ecb0ccd9SWolfgang Denk		A better solution is to properly configure the firewall,
2463ecb0ccd9SWolfgang Denk		but sometimes that is not allowed.
2464ecb0ccd9SWolfgang Denk
2465bf36c5d5SSimon Glass- Hashing support:
2466bf36c5d5SSimon Glass		CONFIG_CMD_HASH
2467bf36c5d5SSimon Glass
2468bf36c5d5SSimon Glass		This enables a generic 'hash' command which can produce
2469bf36c5d5SSimon Glass		hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2470bf36c5d5SSimon Glass
2471bf36c5d5SSimon Glass		CONFIG_HASH_VERIFY
2472bf36c5d5SSimon Glass
2473bf36c5d5SSimon Glass		Enable the hash verify command (hash -v). This adds to code
2474bf36c5d5SSimon Glass		size a little.
2475bf36c5d5SSimon Glass
2476bf36c5d5SSimon Glass		CONFIG_SHA1 - support SHA1 hashing
2477bf36c5d5SSimon Glass		CONFIG_SHA256 - support SHA256 hashing
2478bf36c5d5SSimon Glass
2479bf36c5d5SSimon Glass		Note: There is also a sha1sum command, which should perhaps
2480bf36c5d5SSimon Glass		be deprecated in favour of 'hash sha1'.
2481bf36c5d5SSimon Glass
2482a8c7c708Swdenk- Show boot progress:
2483c609719bSwdenk		CONFIG_SHOW_BOOT_PROGRESS
2484c609719bSwdenk
2485c609719bSwdenk		Defining this option allows to add some board-
2486c609719bSwdenk		specific code (calling a user-provided function
2487c609719bSwdenk		"show_boot_progress(int)") that enables you to show
2488c609719bSwdenk		the system's boot progress on some display (for
2489c609719bSwdenk		example, some LED's) on your board. At the moment,
2490c609719bSwdenk		the following checkpoints are implemented:
2491c609719bSwdenk
24923a608ca0SSimon Glass- Detailed boot stage timing
24933a608ca0SSimon Glass		CONFIG_BOOTSTAGE
24943a608ca0SSimon Glass		Define this option to get detailed timing of each stage
24953a608ca0SSimon Glass		of the boot process.
24963a608ca0SSimon Glass
24973a608ca0SSimon Glass		CONFIG_BOOTSTAGE_USER_COUNT
24983a608ca0SSimon Glass		This is the number of available user bootstage records.
24993a608ca0SSimon Glass		Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
25003a608ca0SSimon Glass		a new ID will be allocated from this stash. If you exceed
25013a608ca0SSimon Glass		the limit, recording will stop.
25023a608ca0SSimon Glass
25033a608ca0SSimon Glass		CONFIG_BOOTSTAGE_REPORT
25043a608ca0SSimon Glass		Define this to print a report before boot, similar to this:
25053a608ca0SSimon Glass
25063a608ca0SSimon Glass		Timer summary in microseconds:
25073a608ca0SSimon Glass		       Mark    Elapsed  Stage
25083a608ca0SSimon Glass			  0          0  reset
25093a608ca0SSimon Glass		  3,575,678  3,575,678  board_init_f start
25103a608ca0SSimon Glass		  3,575,695         17  arch_cpu_init A9
25113a608ca0SSimon Glass		  3,575,777         82  arch_cpu_init done
25123a608ca0SSimon Glass		  3,659,598     83,821  board_init_r start
25133a608ca0SSimon Glass		  3,910,375    250,777  main_loop
25143a608ca0SSimon Glass		 29,916,167 26,005,792  bootm_start
25153a608ca0SSimon Glass		 30,361,327    445,160  start_kernel
25163a608ca0SSimon Glass
25172eba38cfSSimon Glass		CONFIG_CMD_BOOTSTAGE
25182eba38cfSSimon Glass		Add a 'bootstage' command which supports printing a report
25192eba38cfSSimon Glass		and un/stashing of bootstage data.
25202eba38cfSSimon Glass
252194fd1316SSimon Glass		CONFIG_BOOTSTAGE_FDT
252294fd1316SSimon Glass		Stash the bootstage information in the FDT. A root 'bootstage'
252394fd1316SSimon Glass		node is created with each bootstage id as a child. Each child
252494fd1316SSimon Glass		has a 'name' property and either 'mark' containing the
252594fd1316SSimon Glass		mark time in microsecond, or 'accum' containing the
252694fd1316SSimon Glass		accumulated time for that bootstage id in microseconds.
252794fd1316SSimon Glass		For example:
252894fd1316SSimon Glass
252994fd1316SSimon Glass		bootstage {
253094fd1316SSimon Glass			154 {
253194fd1316SSimon Glass				name = "board_init_f";
253294fd1316SSimon Glass				mark = <3575678>;
253394fd1316SSimon Glass			};
253494fd1316SSimon Glass			170 {
253594fd1316SSimon Glass				name = "lcd";
253694fd1316SSimon Glass				accum = <33482>;
253794fd1316SSimon Glass			};
253894fd1316SSimon Glass		};
253994fd1316SSimon Glass
254094fd1316SSimon Glass		Code in the Linux kernel can find this in /proc/devicetree.
254194fd1316SSimon Glass
25421372cce2SMarian BalakowiczLegacy uImage format:
25431372cce2SMarian Balakowicz
2544c609719bSwdenk  Arg	Where			When
2545c609719bSwdenk    1	common/cmd_bootm.c	before attempting to boot an image
2546c609719bSwdenk   -1	common/cmd_bootm.c	Image header has bad	 magic number
2547c609719bSwdenk    2	common/cmd_bootm.c	Image header has correct magic number
2548c609719bSwdenk   -2	common/cmd_bootm.c	Image header has bad	 checksum
2549c609719bSwdenk    3	common/cmd_bootm.c	Image header has correct checksum
2550c609719bSwdenk   -3	common/cmd_bootm.c	Image data   has bad	 checksum
2551c609719bSwdenk    4	common/cmd_bootm.c	Image data   has correct checksum
2552c609719bSwdenk   -4	common/cmd_bootm.c	Image is for unsupported architecture
2553c609719bSwdenk    5	common/cmd_bootm.c	Architecture check OK
25541372cce2SMarian Balakowicz   -5	common/cmd_bootm.c	Wrong Image Type (not kernel, multi)
2555c609719bSwdenk    6	common/cmd_bootm.c	Image Type check OK
2556c609719bSwdenk   -6	common/cmd_bootm.c	gunzip uncompression error
2557c609719bSwdenk   -7	common/cmd_bootm.c	Unimplemented compression type
2558c609719bSwdenk    7	common/cmd_bootm.c	Uncompression OK
25591372cce2SMarian Balakowicz    8	common/cmd_bootm.c	No uncompress/copy overwrite error
2560c609719bSwdenk   -9	common/cmd_bootm.c	Unsupported OS (not Linux, BSD, VxWorks, QNX)
25611372cce2SMarian Balakowicz
25621372cce2SMarian Balakowicz    9	common/image.c		Start initial ramdisk verification
25631372cce2SMarian Balakowicz  -10	common/image.c		Ramdisk header has bad	   magic number
25641372cce2SMarian Balakowicz  -11	common/image.c		Ramdisk header has bad	   checksum
25651372cce2SMarian Balakowicz   10	common/image.c		Ramdisk header is OK
25661372cce2SMarian Balakowicz  -12	common/image.c		Ramdisk data   has bad	   checksum
25671372cce2SMarian Balakowicz   11	common/image.c		Ramdisk data   has correct checksum
25681372cce2SMarian Balakowicz   12	common/image.c		Ramdisk verification complete, start loading
256911ccc33fSMarcel Ziswiler  -13	common/image.c		Wrong Image Type (not PPC Linux ramdisk)
25701372cce2SMarian Balakowicz   13	common/image.c		Start multifile image verification
25711372cce2SMarian Balakowicz   14	common/image.c		No initial ramdisk, no multifile, continue.
25721372cce2SMarian Balakowicz
2573ea0364f1SPeter Tyser   15	arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2574c609719bSwdenk
2575a47a12beSStefan Roese  -30	arch/powerpc/lib/board.c	Fatal error, hang the system
257663e73c9aSwdenk  -31	post/post.c		POST test failed, detected by post_output_backlog()
257763e73c9aSwdenk  -32	post/post.c		POST test failed, detected by post_run_single()
257863e73c9aSwdenk
2579566a494fSHeiko Schocher   34	common/cmd_doc.c	before loading a Image from a DOC device
2580566a494fSHeiko Schocher  -35	common/cmd_doc.c	Bad usage of "doc" command
2581566a494fSHeiko Schocher   35	common/cmd_doc.c	correct usage of "doc" command
2582566a494fSHeiko Schocher  -36	common/cmd_doc.c	No boot device
2583566a494fSHeiko Schocher   36	common/cmd_doc.c	correct boot device
2584566a494fSHeiko Schocher  -37	common/cmd_doc.c	Unknown Chip ID on boot device
2585566a494fSHeiko Schocher   37	common/cmd_doc.c	correct chip ID found, device available
2586566a494fSHeiko Schocher  -38	common/cmd_doc.c	Read Error on boot device
2587566a494fSHeiko Schocher   38	common/cmd_doc.c	reading Image header from DOC device OK
2588566a494fSHeiko Schocher  -39	common/cmd_doc.c	Image header has bad magic number
2589566a494fSHeiko Schocher   39	common/cmd_doc.c	Image header has correct magic number
2590566a494fSHeiko Schocher  -40	common/cmd_doc.c	Error reading Image from DOC device
2591566a494fSHeiko Schocher   40	common/cmd_doc.c	Image header has correct magic number
2592566a494fSHeiko Schocher   41	common/cmd_ide.c	before loading a Image from a IDE device
2593566a494fSHeiko Schocher  -42	common/cmd_ide.c	Bad usage of "ide" command
2594566a494fSHeiko Schocher   42	common/cmd_ide.c	correct usage of "ide" command
2595566a494fSHeiko Schocher  -43	common/cmd_ide.c	No boot device
2596566a494fSHeiko Schocher   43	common/cmd_ide.c	boot device found
2597566a494fSHeiko Schocher  -44	common/cmd_ide.c	Device not available
2598566a494fSHeiko Schocher   44	common/cmd_ide.c	Device available
2599566a494fSHeiko Schocher  -45	common/cmd_ide.c	wrong partition selected
2600566a494fSHeiko Schocher   45	common/cmd_ide.c	partition selected
2601566a494fSHeiko Schocher  -46	common/cmd_ide.c	Unknown partition table
2602566a494fSHeiko Schocher   46	common/cmd_ide.c	valid partition table found
2603566a494fSHeiko Schocher  -47	common/cmd_ide.c	Invalid partition type
2604566a494fSHeiko Schocher   47	common/cmd_ide.c	correct partition type
2605566a494fSHeiko Schocher  -48	common/cmd_ide.c	Error reading Image Header on boot device
2606566a494fSHeiko Schocher   48	common/cmd_ide.c	reading Image Header from IDE device OK
2607566a494fSHeiko Schocher  -49	common/cmd_ide.c	Image header has bad magic number
2608566a494fSHeiko Schocher   49	common/cmd_ide.c	Image header has correct magic number
2609566a494fSHeiko Schocher  -50	common/cmd_ide.c	Image header has bad	 checksum
2610566a494fSHeiko Schocher   50	common/cmd_ide.c	Image header has correct checksum
2611566a494fSHeiko Schocher  -51	common/cmd_ide.c	Error reading Image from IDE device
2612566a494fSHeiko Schocher   51	common/cmd_ide.c	reading Image from IDE device OK
2613566a494fSHeiko Schocher   52	common/cmd_nand.c	before loading a Image from a NAND device
2614566a494fSHeiko Schocher  -53	common/cmd_nand.c	Bad usage of "nand" command
2615566a494fSHeiko Schocher   53	common/cmd_nand.c	correct usage of "nand" command
2616566a494fSHeiko Schocher  -54	common/cmd_nand.c	No boot device
2617566a494fSHeiko Schocher   54	common/cmd_nand.c	boot device found
2618566a494fSHeiko Schocher  -55	common/cmd_nand.c	Unknown Chip ID on boot device
2619566a494fSHeiko Schocher   55	common/cmd_nand.c	correct chip ID found, device available
2620566a494fSHeiko Schocher  -56	common/cmd_nand.c	Error reading Image Header on boot device
2621566a494fSHeiko Schocher   56	common/cmd_nand.c	reading Image Header from NAND device OK
2622566a494fSHeiko Schocher  -57	common/cmd_nand.c	Image header has bad magic number
2623566a494fSHeiko Schocher   57	common/cmd_nand.c	Image header has correct magic number
2624566a494fSHeiko Schocher  -58	common/cmd_nand.c	Error reading Image from NAND device
2625566a494fSHeiko Schocher   58	common/cmd_nand.c	reading Image from NAND device OK
2626c609719bSwdenk
2627566a494fSHeiko Schocher  -60	common/env_common.c	Environment has a bad CRC, using default
2628c609719bSwdenk
2629566a494fSHeiko Schocher   64	net/eth.c		starting with Ethernet configuration.
2630566a494fSHeiko Schocher  -64	net/eth.c		no Ethernet found.
2631566a494fSHeiko Schocher   65	net/eth.c		Ethernet found.
2632206c60cbSwdenk
2633566a494fSHeiko Schocher  -80	common/cmd_net.c	usage wrong
2634566a494fSHeiko Schocher   80	common/cmd_net.c	before calling NetLoop()
263511ccc33fSMarcel Ziswiler  -81	common/cmd_net.c	some error in NetLoop() occurred
2636566a494fSHeiko Schocher   81	common/cmd_net.c	NetLoop() back without error
2637566a494fSHeiko Schocher  -82	common/cmd_net.c	size == 0 (File with size 0 loaded)
2638566a494fSHeiko Schocher   82	common/cmd_net.c	trying automatic boot
263974de7aefSWolfgang Denk   83	common/cmd_net.c	running "source" command
264074de7aefSWolfgang Denk  -83	common/cmd_net.c	some error in automatic boot or "source" command
2641566a494fSHeiko Schocher   84	common/cmd_net.c	end without errors
2642c609719bSwdenk
26431372cce2SMarian BalakowiczFIT uImage format:
26441372cce2SMarian Balakowicz
26451372cce2SMarian Balakowicz  Arg	Where			When
26461372cce2SMarian Balakowicz  100	common/cmd_bootm.c	Kernel FIT Image has correct format
26471372cce2SMarian Balakowicz -100	common/cmd_bootm.c	Kernel FIT Image has incorrect format
26481372cce2SMarian Balakowicz  101	common/cmd_bootm.c	No Kernel subimage unit name, using configuration
26491372cce2SMarian Balakowicz -101	common/cmd_bootm.c	Can't get configuration for kernel subimage
26501372cce2SMarian Balakowicz  102	common/cmd_bootm.c	Kernel unit name specified
26511372cce2SMarian Balakowicz -103	common/cmd_bootm.c	Can't get kernel subimage node offset
2652f773bea8SMarian Balakowicz  103	common/cmd_bootm.c	Found configuration node
26531372cce2SMarian Balakowicz  104	common/cmd_bootm.c	Got kernel subimage node offset
26541372cce2SMarian Balakowicz -104	common/cmd_bootm.c	Kernel subimage hash verification failed
26551372cce2SMarian Balakowicz  105	common/cmd_bootm.c	Kernel subimage hash verification OK
26561372cce2SMarian Balakowicz -105	common/cmd_bootm.c	Kernel subimage is for unsupported architecture
26571372cce2SMarian Balakowicz  106	common/cmd_bootm.c	Architecture check OK
265811ccc33fSMarcel Ziswiler -106	common/cmd_bootm.c	Kernel subimage has wrong type
265911ccc33fSMarcel Ziswiler  107	common/cmd_bootm.c	Kernel subimage type OK
26601372cce2SMarian Balakowicz -107	common/cmd_bootm.c	Can't get kernel subimage data/size
26611372cce2SMarian Balakowicz  108	common/cmd_bootm.c	Got kernel subimage data/size
26621372cce2SMarian Balakowicz -108	common/cmd_bootm.c	Wrong image type (not legacy, FIT)
26631372cce2SMarian Balakowicz -109	common/cmd_bootm.c	Can't get kernel subimage type
26641372cce2SMarian Balakowicz -110	common/cmd_bootm.c	Can't get kernel subimage comp
26651372cce2SMarian Balakowicz -111	common/cmd_bootm.c	Can't get kernel subimage os
26661372cce2SMarian Balakowicz -112	common/cmd_bootm.c	Can't get kernel subimage load address
26671372cce2SMarian Balakowicz -113	common/cmd_bootm.c	Image uncompress/copy overwrite error
26681372cce2SMarian Balakowicz
26691372cce2SMarian Balakowicz  120	common/image.c		Start initial ramdisk verification
26701372cce2SMarian Balakowicz -120	common/image.c		Ramdisk FIT image has incorrect format
26711372cce2SMarian Balakowicz  121	common/image.c		Ramdisk FIT image has correct format
267211ccc33fSMarcel Ziswiler  122	common/image.c		No ramdisk subimage unit name, using configuration
26731372cce2SMarian Balakowicz -122	common/image.c		Can't get configuration for ramdisk subimage
26741372cce2SMarian Balakowicz  123	common/image.c		Ramdisk unit name specified
26751372cce2SMarian Balakowicz -124	common/image.c		Can't get ramdisk subimage node offset
26761372cce2SMarian Balakowicz  125	common/image.c		Got ramdisk subimage node offset
26771372cce2SMarian Balakowicz -125	common/image.c		Ramdisk subimage hash verification failed
26781372cce2SMarian Balakowicz  126	common/image.c		Ramdisk subimage hash verification OK
26791372cce2SMarian Balakowicz -126	common/image.c		Ramdisk subimage for unsupported architecture
26801372cce2SMarian Balakowicz  127	common/image.c		Architecture check OK
26811372cce2SMarian Balakowicz -127	common/image.c		Can't get ramdisk subimage data/size
26821372cce2SMarian Balakowicz  128	common/image.c		Got ramdisk subimage data/size
26831372cce2SMarian Balakowicz  129	common/image.c		Can't get ramdisk load address
26841372cce2SMarian Balakowicz -129	common/image.c		Got ramdisk load address
26851372cce2SMarian Balakowicz
268611ccc33fSMarcel Ziswiler -130	common/cmd_doc.c	Incorrect FIT image format
26871372cce2SMarian Balakowicz  131	common/cmd_doc.c	FIT image format OK
26881372cce2SMarian Balakowicz
268911ccc33fSMarcel Ziswiler -140	common/cmd_ide.c	Incorrect FIT image format
26901372cce2SMarian Balakowicz  141	common/cmd_ide.c	FIT image format OK
26911372cce2SMarian Balakowicz
269211ccc33fSMarcel Ziswiler -150	common/cmd_nand.c	Incorrect FIT image format
26931372cce2SMarian Balakowicz  151	common/cmd_nand.c	FIT image format OK
26941372cce2SMarian Balakowicz
2695d95f6ec7SGabe Black- FIT image support:
2696d95f6ec7SGabe Black		CONFIG_FIT
2697d95f6ec7SGabe Black		Enable support for the FIT uImage format.
2698d95f6ec7SGabe Black
2699d95f6ec7SGabe Black		CONFIG_FIT_BEST_MATCH
2700d95f6ec7SGabe Black		When no configuration is explicitly selected, default to the
2701d95f6ec7SGabe Black		one whose fdt's compatibility field best matches that of
2702d95f6ec7SGabe Black		U-Boot itself. A match is considered "best" if it matches the
2703d95f6ec7SGabe Black		most specific compatibility entry of U-Boot's fdt's root node.
2704d95f6ec7SGabe Black		The order of entries in the configuration's fdt is ignored.
2705d95f6ec7SGabe Black
27064cf2609bSWolfgang Denk- Standalone program support:
27074cf2609bSWolfgang Denk		CONFIG_STANDALONE_LOAD_ADDR
27084cf2609bSWolfgang Denk
27096feff899SWolfgang Denk		This option defines a board specific value for the
27106feff899SWolfgang Denk		address where standalone program gets loaded, thus
27116feff899SWolfgang Denk		overwriting the architecture dependent default
27124cf2609bSWolfgang Denk		settings.
27134cf2609bSWolfgang Denk
27144cf2609bSWolfgang Denk- Frame Buffer Address:
27154cf2609bSWolfgang Denk		CONFIG_FB_ADDR
27164cf2609bSWolfgang Denk
27174cf2609bSWolfgang Denk		Define CONFIG_FB_ADDR if you want to use specific
271844a53b57SWolfgang Denk		address for frame buffer.  This is typically the case
271944a53b57SWolfgang Denk		when using a graphics controller has separate video
272044a53b57SWolfgang Denk		memory.  U-Boot will then place the frame buffer at
272144a53b57SWolfgang Denk		the given address instead of dynamically reserving it
272244a53b57SWolfgang Denk		in system RAM by calling lcd_setmem(), which grabs
272344a53b57SWolfgang Denk		the memory for the frame buffer depending on the
272444a53b57SWolfgang Denk		configured panel size.
27254cf2609bSWolfgang Denk
27264cf2609bSWolfgang Denk		Please see board_init_f function.
27274cf2609bSWolfgang Denk
2728cccfc2abSDetlev Zundel- Automatic software updates via TFTP server
2729cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP
2730cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP_CNT_MAX
2731cccfc2abSDetlev Zundel		CONFIG_UPDATE_TFTP_MSEC_MAX
2732cccfc2abSDetlev Zundel
2733cccfc2abSDetlev Zundel		These options enable and control the auto-update feature;
2734cccfc2abSDetlev Zundel		for a more detailed description refer to doc/README.update.
2735cccfc2abSDetlev Zundel
2736cccfc2abSDetlev Zundel- MTD Support (mtdparts command, UBI support)
2737cccfc2abSDetlev Zundel		CONFIG_MTD_DEVICE
2738cccfc2abSDetlev Zundel
2739cccfc2abSDetlev Zundel		Adds the MTD device infrastructure from the Linux kernel.
2740cccfc2abSDetlev Zundel		Needed for mtdparts command support.
2741cccfc2abSDetlev Zundel
2742cccfc2abSDetlev Zundel		CONFIG_MTD_PARTITIONS
2743cccfc2abSDetlev Zundel
2744cccfc2abSDetlev Zundel		Adds the MTD partitioning infrastructure from the Linux
2745cccfc2abSDetlev Zundel		kernel. Needed for UBI support.
2746cccfc2abSDetlev Zundel
27476a11cf48SDaniel Schwierzeck- SPL framework
27486a11cf48SDaniel Schwierzeck		CONFIG_SPL
27496a11cf48SDaniel Schwierzeck		Enable building of SPL globally.
27506a11cf48SDaniel Schwierzeck
275195579793STom Rini		CONFIG_SPL_LDSCRIPT
275295579793STom Rini		LDSCRIPT for linking the SPL binary.
275395579793STom Rini
275495579793STom Rini		CONFIG_SPL_MAX_SIZE
275595579793STom Rini		Maximum binary size (text, data and rodata) of the SPL binary.
275695579793STom Rini
27576a11cf48SDaniel Schwierzeck		CONFIG_SPL_TEXT_BASE
27586a11cf48SDaniel Schwierzeck		TEXT_BASE for linking the SPL binary.
27596a11cf48SDaniel Schwierzeck
276094a45bb1SScott Wood		CONFIG_SPL_RELOC_TEXT_BASE
276194a45bb1SScott Wood		Address to relocate to.  If unspecified, this is equal to
276294a45bb1SScott Wood		CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
276394a45bb1SScott Wood
276495579793STom Rini		CONFIG_SPL_BSS_START_ADDR
276595579793STom Rini		Link address for the BSS within the SPL binary.
276695579793STom Rini
276795579793STom Rini		CONFIG_SPL_BSS_MAX_SIZE
276895579793STom Rini		Maximum binary size of the BSS section of the SPL binary.
276995579793STom Rini
277095579793STom Rini		CONFIG_SPL_STACK
277195579793STom Rini		Adress of the start of the stack SPL will use
277295579793STom Rini
277394a45bb1SScott Wood		CONFIG_SPL_RELOC_STACK
277494a45bb1SScott Wood		Adress of the start of the stack SPL will use after
277594a45bb1SScott Wood		relocation.  If unspecified, this is equal to
277694a45bb1SScott Wood		CONFIG_SPL_STACK.
277794a45bb1SScott Wood
277895579793STom Rini		CONFIG_SYS_SPL_MALLOC_START
277995579793STom Rini		Starting address of the malloc pool used in SPL.
278095579793STom Rini
278195579793STom Rini		CONFIG_SYS_SPL_MALLOC_SIZE
278295579793STom Rini		The size of the malloc pool used in SPL.
27836a11cf48SDaniel Schwierzeck
278447f7bcaeSTom Rini		CONFIG_SPL_FRAMEWORK
278547f7bcaeSTom Rini		Enable the SPL framework under common/.  This framework
278647f7bcaeSTom Rini		supports MMC, NAND and YMODEM loading of U-Boot and NAND
278747f7bcaeSTom Rini		NAND loading of the Linux Kernel.
278847f7bcaeSTom Rini
2789861a86f4STom Rini		CONFIG_SPL_DISPLAY_PRINT
2790861a86f4STom Rini		For ARM, enable an optional function to print more information
2791861a86f4STom Rini		about the running system.
2792861a86f4STom Rini
27934b919725SScott Wood		CONFIG_SPL_INIT_MINIMAL
27944b919725SScott Wood		Arch init code should be built for a very small image
27954b919725SScott Wood
27966a11cf48SDaniel Schwierzeck		CONFIG_SPL_LIBCOMMON_SUPPORT
27976a11cf48SDaniel Schwierzeck		Support for common/libcommon.o in SPL binary
27986a11cf48SDaniel Schwierzeck
27996a11cf48SDaniel Schwierzeck		CONFIG_SPL_LIBDISK_SUPPORT
28006a11cf48SDaniel Schwierzeck		Support for disk/libdisk.o in SPL binary
28016a11cf48SDaniel Schwierzeck
28026a11cf48SDaniel Schwierzeck		CONFIG_SPL_I2C_SUPPORT
28036a11cf48SDaniel Schwierzeck		Support for drivers/i2c/libi2c.o in SPL binary
28046a11cf48SDaniel Schwierzeck
28056a11cf48SDaniel Schwierzeck		CONFIG_SPL_GPIO_SUPPORT
28066a11cf48SDaniel Schwierzeck		Support for drivers/gpio/libgpio.o in SPL binary
28076a11cf48SDaniel Schwierzeck
28086a11cf48SDaniel Schwierzeck		CONFIG_SPL_MMC_SUPPORT
28096a11cf48SDaniel Schwierzeck		Support for drivers/mmc/libmmc.o in SPL binary
28106a11cf48SDaniel Schwierzeck
281195579793STom Rini		CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
281295579793STom Rini		CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
281395579793STom Rini		CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
281495579793STom Rini		Address, size and partition on the MMC to load U-Boot from
281595579793STom Rini		when the MMC is being used in raw mode.
281695579793STom Rini
281795579793STom Rini		CONFIG_SPL_FAT_SUPPORT
281895579793STom Rini		Support for fs/fat/libfat.o in SPL binary
281995579793STom Rini
282095579793STom Rini		CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
282195579793STom Rini		Filename to read to load U-Boot when reading from FAT
282295579793STom Rini
282306f60ae3SScott Wood		CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
282406f60ae3SScott Wood		Set this for NAND SPL on PPC mpc83xx targets, so that
282506f60ae3SScott Wood		start.S waits for the rest of the SPL to load before
282606f60ae3SScott Wood		continuing (the hardware starts execution after just
282706f60ae3SScott Wood		loading the first page rather than the full 4K).
282806f60ae3SScott Wood
28296f2f01b9SScott Wood		CONFIG_SPL_NAND_BASE
28306f2f01b9SScott Wood		Include nand_base.c in the SPL.  Requires
28316f2f01b9SScott Wood		CONFIG_SPL_NAND_DRIVERS.
28326f2f01b9SScott Wood
28336f2f01b9SScott Wood		CONFIG_SPL_NAND_DRIVERS
28346f2f01b9SScott Wood		SPL uses normal NAND drivers, not minimal drivers.
28356f2f01b9SScott Wood
28366f2f01b9SScott Wood		CONFIG_SPL_NAND_ECC
28376f2f01b9SScott Wood		Include standard software ECC in the SPL
28386f2f01b9SScott Wood
283995579793STom Rini		CONFIG_SPL_NAND_SIMPLE
28407d4b7955SScott Wood		Support for NAND boot using simple NAND drivers that
28417d4b7955SScott Wood		expose the cmd_ctrl() interface.
284295579793STom Rini
284395579793STom Rini		CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
284495579793STom Rini		CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
284595579793STom Rini		CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
284695579793STom Rini		CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
284795579793STom Rini		CONFIG_SYS_NAND_ECCBYTES
284895579793STom Rini		Defines the size and behavior of the NAND that SPL uses
28497d4b7955SScott Wood		to read U-Boot
285095579793STom Rini
285195579793STom Rini		CONFIG_SYS_NAND_U_BOOT_OFFS
28527d4b7955SScott Wood		Location in NAND to read U-Boot from
28537d4b7955SScott Wood
28547d4b7955SScott Wood		CONFIG_SYS_NAND_U_BOOT_DST
28557d4b7955SScott Wood		Location in memory to load U-Boot to
28567d4b7955SScott Wood
28577d4b7955SScott Wood		CONFIG_SYS_NAND_U_BOOT_SIZE
28587d4b7955SScott Wood		Size of image to load
285995579793STom Rini
286095579793STom Rini		CONFIG_SYS_NAND_U_BOOT_START
28617d4b7955SScott Wood		Entry point in loaded image to jump to
286295579793STom Rini
286395579793STom Rini		CONFIG_SYS_NAND_HW_ECC_OOBFIRST
286495579793STom Rini		Define this if you need to first read the OOB and then the
286595579793STom Rini		data. This is used for example on davinci plattforms.
286695579793STom Rini
286795579793STom Rini		CONFIG_SPL_OMAP3_ID_NAND
286895579793STom Rini		Support for an OMAP3-specific set of functions to return the
286995579793STom Rini		ID and MFR of the first attached NAND chip, if present.
287095579793STom Rini
28716a11cf48SDaniel Schwierzeck		CONFIG_SPL_SERIAL_SUPPORT
28726a11cf48SDaniel Schwierzeck		Support for drivers/serial/libserial.o in SPL binary
28736a11cf48SDaniel Schwierzeck
28746a11cf48SDaniel Schwierzeck		CONFIG_SPL_SPI_FLASH_SUPPORT
28756a11cf48SDaniel Schwierzeck		Support for drivers/mtd/spi/libspi_flash.o in SPL binary
28766a11cf48SDaniel Schwierzeck
28776a11cf48SDaniel Schwierzeck		CONFIG_SPL_SPI_SUPPORT
28786a11cf48SDaniel Schwierzeck		Support for drivers/spi/libspi.o in SPL binary
28796a11cf48SDaniel Schwierzeck
2880c57b953dSPavel Machek		CONFIG_SPL_RAM_DEVICE
2881c57b953dSPavel Machek		Support for running image already present in ram, in SPL binary
2882c57b953dSPavel Machek
28836a11cf48SDaniel Schwierzeck		CONFIG_SPL_LIBGENERIC_SUPPORT
28846a11cf48SDaniel Schwierzeck		Support for lib/libgeneric.o in SPL binary
28851372cce2SMarian Balakowicz
288674752baaSScott Wood		CONFIG_SPL_PAD_TO
288774752baaSScott Wood		Linker address to which the SPL should be padded before
288874752baaSScott Wood		appending the SPL payload.
288974752baaSScott Wood
2890ca2fca22SScott Wood		CONFIG_SPL_TARGET
2891ca2fca22SScott Wood		Final target image containing SPL and payload.  Some SPLs
2892ca2fca22SScott Wood		use an arch-specific makefile fragment instead, for
2893ca2fca22SScott Wood		example if more than one image needs to be produced.
2894ca2fca22SScott Wood
2895c609719bSwdenkModem Support:
2896c609719bSwdenk--------------
2897c609719bSwdenk
2898566e5cf4SWolfgang Denk[so far only for SMDK2400 boards]
2899c609719bSwdenk
290011ccc33fSMarcel Ziswiler- Modem support enable:
2901c609719bSwdenk		CONFIG_MODEM_SUPPORT
2902c609719bSwdenk
2903c609719bSwdenk- RTS/CTS Flow control enable:
2904c609719bSwdenk		CONFIG_HWFLOW
2905c609719bSwdenk
2906c609719bSwdenk- Modem debug support:
2907c609719bSwdenk		CONFIG_MODEM_SUPPORT_DEBUG
2908c609719bSwdenk
2909c609719bSwdenk		Enables debugging stuff (char screen[1024], dbg())
2910c609719bSwdenk		for modem support. Useful only with BDI2000.
2911c609719bSwdenk
2912a8c7c708Swdenk- Interrupt support (PPC):
2913a8c7c708Swdenk
2914a8c7c708Swdenk		There are common interrupt_init() and timer_interrupt()
2915a8c7c708Swdenk		for all PPC archs. interrupt_init() calls interrupt_init_cpu()
291611ccc33fSMarcel Ziswiler		for CPU specific initialization. interrupt_init_cpu()
2917a8c7c708Swdenk		should set decrementer_count to appropriate value. If
291811ccc33fSMarcel Ziswiler		CPU resets decrementer automatically after interrupt
2919a8c7c708Swdenk		(ppc4xx) it should set decrementer_count to zero.
292011ccc33fSMarcel Ziswiler		timer_interrupt() calls timer_interrupt_cpu() for CPU
2921a8c7c708Swdenk		specific handling. If board has watchdog / status_led
2922a8c7c708Swdenk		/ other_activity_monitor it works automatically from
2923a8c7c708Swdenk		general timer_interrupt().
2924a8c7c708Swdenk
2925c609719bSwdenk- General:
2926c609719bSwdenk
2927c609719bSwdenk		In the target system modem support is enabled when a
2928c609719bSwdenk		specific key (key combination) is pressed during
2929c609719bSwdenk		power-on. Otherwise U-Boot will boot normally
293011ccc33fSMarcel Ziswiler		(autoboot). The key_pressed() function is called from
2931c609719bSwdenk		board_init(). Currently key_pressed() is a dummy
2932c609719bSwdenk		function, returning 1 and thus enabling modem
2933c609719bSwdenk		initialization.
2934c609719bSwdenk
2935c609719bSwdenk		If there are no modem init strings in the
2936c609719bSwdenk		environment, U-Boot proceed to autoboot; the
2937c609719bSwdenk		previous output (banner, info printfs) will be
293811ccc33fSMarcel Ziswiler		suppressed, though.
2939c609719bSwdenk
2940c609719bSwdenk		See also: doc/README.Modem
2941c609719bSwdenk
29429660e442SHelmut RaigerBoard initialization settings:
29439660e442SHelmut Raiger------------------------------
29449660e442SHelmut Raiger
29459660e442SHelmut RaigerDuring Initialization u-boot calls a number of board specific functions
29469660e442SHelmut Raigerto allow the preparation of board specific prerequisites, e.g. pin setup
29479660e442SHelmut Raigerbefore drivers are initialized. To enable these callbacks the
29489660e442SHelmut Raigerfollowing configuration macros have to be defined. Currently this is
29499660e442SHelmut Raigerarchitecture specific, so please check arch/your_architecture/lib/board.c
29509660e442SHelmut Raigertypically in board_init_f() and board_init_r().
29519660e442SHelmut Raiger
29529660e442SHelmut Raiger- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
29539660e442SHelmut Raiger- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
29549660e442SHelmut Raiger- CONFIG_BOARD_LATE_INIT: Call board_late_init()
29559660e442SHelmut Raiger- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
2956c609719bSwdenk
2957c609719bSwdenkConfiguration Settings:
2958c609719bSwdenk-----------------------
2959c609719bSwdenk
29606d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2961c609719bSwdenk		undefine this when you're short of memory.
2962c609719bSwdenk
29632fb2604dSPeter Tyser- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
29642fb2604dSPeter Tyser		width of the commands listed in the 'help' command output.
29652fb2604dSPeter Tyser
29666d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PROMPT:	This is what U-Boot prints on the console to
2967c609719bSwdenk		prompt for user input.
2968c609719bSwdenk
29696d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CBSIZE:	Buffer size for input from the Console
2970c609719bSwdenk
29716d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PBSIZE:	Buffer size for Console output
2972c609719bSwdenk
29736d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAXARGS:	max. Number of arguments accepted for monitor commands
2974c609719bSwdenk
29756d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2976c609719bSwdenk		the application (usually a Linux kernel) when it is
2977c609719bSwdenk		booted
2978c609719bSwdenk
29796d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BAUDRATE_TABLE:
2980c609719bSwdenk		List of legal baudrate settings for this board.
2981c609719bSwdenk
29826d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CONSOLE_INFO_QUIET
2983c609719bSwdenk		Suppress display of console information at boot.
2984c609719bSwdenk
29856d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CONSOLE_IS_IN_ENV
2986c609719bSwdenk		If the board specific function
2987c609719bSwdenk			extern int overwrite_console (void);
2988c609719bSwdenk		returns 1, the stdin, stderr and stdout are switched to the
2989c609719bSwdenk		serial port, else the settings in the environment are used.
2990c609719bSwdenk
29916d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2992c609719bSwdenk		Enable the call to overwrite_console().
2993c609719bSwdenk
29946d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2995c609719bSwdenk		Enable overwrite of previous console environment settings.
2996c609719bSwdenk
29976d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2998c609719bSwdenk		Begin and End addresses of the area used by the
2999c609719bSwdenk		simple memory test.
3000c609719bSwdenk
30016d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_ALT_MEMTEST:
3002c609719bSwdenk		Enable an alternate, more extensive memory test.
3003c609719bSwdenk
30046d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MEMTEST_SCRATCH:
30055f535fe1Swdenk		Scratch address used by the alternate memory test
30065f535fe1Swdenk		You only need to set this if address zero isn't writeable
30075f535fe1Swdenk
30086d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MEM_TOP_HIDE (PPC only):
30096d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
301014f73ca6SStefan Roese		this specified memory area will get subtracted from the top
301111ccc33fSMarcel Ziswiler		(end) of RAM and won't get "touched" at all by U-Boot. By
301214f73ca6SStefan Roese		fixing up gd->ram_size the Linux kernel should gets passed
301314f73ca6SStefan Roese		the now "corrected" memory size and won't touch it either.
301414f73ca6SStefan Roese		This should work for arch/ppc and arch/powerpc. Only Linux
30155e12e75dSStefan Roese		board ports in arch/powerpc with bootwrapper support that
301614f73ca6SStefan Roese		recalculate the memory size from the SDRAM controller setup
30175e12e75dSStefan Roese		will have to get fixed in Linux additionally.
301814f73ca6SStefan Roese
301914f73ca6SStefan Roese		This option can be used as a workaround for the 440EPx/GRx
302014f73ca6SStefan Roese		CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
302114f73ca6SStefan Roese		be touched.
302214f73ca6SStefan Roese
302314f73ca6SStefan Roese		WARNING: Please make sure that this value is a multiple of
302414f73ca6SStefan Roese		the Linux page size (normally 4k). If this is not the case,
302514f73ca6SStefan Roese		then the end address of the Linux memory will be located at a
302614f73ca6SStefan Roese		non page size aligned address and this could cause major
302714f73ca6SStefan Roese		problems.
302814f73ca6SStefan Roese
30296d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_LOADS_BAUD_CHANGE:
3030c609719bSwdenk		Enable temporary baudrate change while serial download
3031c609719bSwdenk
30326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SDRAM_BASE:
3033c609719bSwdenk		Physical start address of SDRAM. _Must_ be 0 here.
3034c609719bSwdenk
30356d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MBIO_BASE:
3036c609719bSwdenk		Physical start address of Motherboard I/O (if using a
3037c609719bSwdenk		Cogent motherboard)
3038c609719bSwdenk
30396d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_BASE:
3040c609719bSwdenk		Physical start address of Flash memory.
3041c609719bSwdenk
30426d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MONITOR_BASE:
3043c609719bSwdenk		Physical start address of boot monitor code (set by
3044c609719bSwdenk		make config files to be same as the text base address
304514d0a02aSWolfgang Denk		(CONFIG_SYS_TEXT_BASE) used when linking) - same as
30466d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FLASH_BASE when booting from flash.
3047c609719bSwdenk
30486d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MONITOR_LEN:
30493b57fe0aSwdenk		Size of memory reserved for monitor code, used to
30503b57fe0aSwdenk		determine _at_compile_time_ (!) if the environment is
30513b57fe0aSwdenk		embedded within the U-Boot image, or in a separate
30523b57fe0aSwdenk		flash sector.
3053c609719bSwdenk
30546d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MALLOC_LEN:
3055c609719bSwdenk		Size of DRAM reserved for malloc() use.
3056c609719bSwdenk
30576d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BOOTM_LEN:
305815940c9aSStefan Roese		Normally compressed uImages are limited to an
305915940c9aSStefan Roese		uncompressed size of 8 MBytes. If this is not enough,
30606d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		you can define CONFIG_SYS_BOOTM_LEN in your board config file
306115940c9aSStefan Roese		to adjust this setting to your needs.
3062c609719bSwdenk
30636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_BOOTMAPSZ:
3064c609719bSwdenk		Maximum size of memory mapped by the startup code of
3065c609719bSwdenk		the Linux kernel; all data that must be processed by
30667d721e34SBartlomiej Sieka		the Linux kernel (bd_info, boot arguments, FDT blob if
30677d721e34SBartlomiej Sieka		used) must be put below this limit, unless "bootm_low"
30687d721e34SBartlomiej Sieka		enviroment variable is defined and non-zero. In such case
30697d721e34SBartlomiej Sieka		all data for the Linux kernel must be between "bootm_low"
3070c3624e6eSGrant Likely		and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.	 The environment
3071c3624e6eSGrant Likely		variable "bootm_mapsize" will override the value of
3072c3624e6eSGrant Likely		CONFIG_SYS_BOOTMAPSZ.  If CONFIG_SYS_BOOTMAPSZ is undefined,
3073c3624e6eSGrant Likely		then the value in "bootm_size" will be used instead.
3074c609719bSwdenk
3075fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_RAMDISK_HIGH:
3076fca43cc8SJohn Rigby		Enable initrd_high functionality.  If defined then the
3077fca43cc8SJohn Rigby		initrd_high feature is enabled and the bootm ramdisk subcommand
3078fca43cc8SJohn Rigby		is enabled.
3079fca43cc8SJohn Rigby
3080fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_GET_CMDLINE:
3081fca43cc8SJohn Rigby		Enables allocating and saving kernel cmdline in space between
3082fca43cc8SJohn Rigby		"bootm_low" and "bootm_low" + BOOTMAPSZ.
3083fca43cc8SJohn Rigby
3084fca43cc8SJohn Rigby- CONFIG_SYS_BOOT_GET_KBD:
3085fca43cc8SJohn Rigby		Enables allocating and saving a kernel copy of the bd_info in
3086fca43cc8SJohn Rigby		space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3087fca43cc8SJohn Rigby
30886d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAX_FLASH_BANKS:
3089c609719bSwdenk		Max number of Flash memory banks
3090c609719bSwdenk
30916d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAX_FLASH_SECT:
3092c609719bSwdenk		Max number of sectors on a Flash chip
3093c609719bSwdenk
30946d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_ERASE_TOUT:
3095c609719bSwdenk		Timeout for Flash erase operations (in ms)
3096c609719bSwdenk
30976d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_WRITE_TOUT:
3098c609719bSwdenk		Timeout for Flash write operations (in ms)
3099c609719bSwdenk
31006d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_LOCK_TOUT
31018564acf9Swdenk		Timeout for Flash set sector lock bit operation (in ms)
31028564acf9Swdenk
31036d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_UNLOCK_TOUT
31048564acf9Swdenk		Timeout for Flash clear lock bits operation (in ms)
31058564acf9Swdenk
31066d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_PROTECTION
31078564acf9Swdenk		If defined, hardware flash sectors protection is used
31088564acf9Swdenk		instead of U-Boot software protection.
31098564acf9Swdenk
31106d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_DIRECT_FLASH_TFTP:
3111c609719bSwdenk
3112c609719bSwdenk		Enable TFTP transfers directly to flash memory;
3113c609719bSwdenk		without this option such a download has to be
3114c609719bSwdenk		performed in two steps: (1) download to RAM, and (2)
3115c609719bSwdenk		copy from RAM to flash.
3116c609719bSwdenk
3117c609719bSwdenk		The two-step approach is usually more reliable, since
3118c609719bSwdenk		you can check if the download worked before you erase
311911ccc33fSMarcel Ziswiler		the flash, but in some situations (when system RAM is
312011ccc33fSMarcel Ziswiler		too limited to allow for a temporary copy of the
3121c609719bSwdenk		downloaded image) this option may be very useful.
3122c609719bSwdenk
31236d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_CFI:
3124c609719bSwdenk		Define if the flash driver uses extra elements in the
31255653fc33Swdenk		common flash structure for storing flash geometry.
31265653fc33Swdenk
312700b1883aSJean-Christophe PLAGNIOL-VILLARD- CONFIG_FLASH_CFI_DRIVER
31285653fc33Swdenk		This option also enables the building of the cfi_flash driver
31295653fc33Swdenk		in the drivers directory
313053cf9435Sstroese
313191809ed5SPiotr Ziecik- CONFIG_FLASH_CFI_MTD
313291809ed5SPiotr Ziecik		This option enables the building of the cfi_mtd driver
313391809ed5SPiotr Ziecik		in the drivers directory. The driver exports CFI flash
313491809ed5SPiotr Ziecik		to the MTD layer.
313591809ed5SPiotr Ziecik
31366d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
313796ef831fSGuennadi Liakhovetski		Use buffered writes to flash.
313896ef831fSGuennadi Liakhovetski
313996ef831fSGuennadi Liakhovetski- CONFIG_FLASH_SPANSION_S29WS_N
314096ef831fSGuennadi Liakhovetski		s29ws-n MirrorBit flash has non-standard addresses for buffered
314196ef831fSGuennadi Liakhovetski		write commands.
314296ef831fSGuennadi Liakhovetski
31436d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FLASH_QUIET_TEST
31445568e613SStefan Roese		If this option is defined, the common CFI flash doesn't
31455568e613SStefan Roese		print it's warning upon not recognized FLASH banks. This
31465568e613SStefan Roese		is useful, if some of the configured banks are only
31475568e613SStefan Roese		optionally available.
31485568e613SStefan Roese
31499a042e9cSJerry Van Baren- CONFIG_FLASH_SHOW_PROGRESS
31509a042e9cSJerry Van Baren		If defined (must be an integer), print out countdown
31519a042e9cSJerry Van Baren		digits and dots.  Recommended value: 45 (9..1) for 80
31529a042e9cSJerry Van Baren		column displays, 15 (3..1) for 40 column displays.
31539a042e9cSJerry Van Baren
31546d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_RX_ETH_BUFFER:
315511ccc33fSMarcel Ziswiler		Defines the number of Ethernet receive buffers. On some
315611ccc33fSMarcel Ziswiler		Ethernet controllers it is recommended to set this value
315753cf9435Sstroese		to 8 or even higher (EEPRO100 or 405 EMAC), since all
315853cf9435Sstroese		buffers can be full shortly after enabling the interface
315911ccc33fSMarcel Ziswiler		on high Ethernet traffic.
316053cf9435Sstroese		Defaults to 4 if not defined.
3161c609719bSwdenk
3162ea882bafSWolfgang Denk- CONFIG_ENV_MAX_ENTRIES
3163ea882bafSWolfgang Denk
3164ea882bafSWolfgang Denk	Maximum number of entries in the hash table that is used
3165ea882bafSWolfgang Denk	internally to store the environment settings. The default
3166ea882bafSWolfgang Denk	setting is supposed to be generous and should work in most
3167ea882bafSWolfgang Denk	cases. This setting can be used to tune behaviour; see
3168ea882bafSWolfgang Denk	lib/hashtable.c for details.
3169ea882bafSWolfgang Denk
31702598090bSJoe Hershberger- CONFIG_ENV_FLAGS_LIST_DEFAULT
31712598090bSJoe Hershberger- CONFIG_ENV_FLAGS_LIST_STATIC
31722598090bSJoe Hershberger	Enable validation of the values given to enviroment variables when
31732598090bSJoe Hershberger	calling env set.  Variables can be restricted to only decimal,
31742598090bSJoe Hershberger	hexadecimal, or boolean.  If CONFIG_CMD_NET is also defined,
31752598090bSJoe Hershberger	the variables can also be restricted to IP address or MAC address.
31762598090bSJoe Hershberger
31772598090bSJoe Hershberger	The format of the list is:
31782598090bSJoe Hershberger		type_attribute = [s|d|x|b|i|m]
3179267541f7SJoe Hershberger		access_atribute = [a|r|o|c]
3180267541f7SJoe Hershberger		attributes = type_attribute[access_atribute]
31812598090bSJoe Hershberger		entry = variable_name[:attributes]
31822598090bSJoe Hershberger		list = entry[,list]
31832598090bSJoe Hershberger
31842598090bSJoe Hershberger	The type attributes are:
31852598090bSJoe Hershberger		s - String (default)
31862598090bSJoe Hershberger		d - Decimal
31872598090bSJoe Hershberger		x - Hexadecimal
31882598090bSJoe Hershberger		b - Boolean ([1yYtT|0nNfF])
31892598090bSJoe Hershberger		i - IP address
31902598090bSJoe Hershberger		m - MAC address
31912598090bSJoe Hershberger
3192267541f7SJoe Hershberger	The access attributes are:
3193267541f7SJoe Hershberger		a - Any (default)
3194267541f7SJoe Hershberger		r - Read-only
3195267541f7SJoe Hershberger		o - Write-once
3196267541f7SJoe Hershberger		c - Change-default
3197267541f7SJoe Hershberger
31982598090bSJoe Hershberger	- CONFIG_ENV_FLAGS_LIST_DEFAULT
31992598090bSJoe Hershberger		Define this to a list (string) to define the ".flags"
32002598090bSJoe Hershberger		envirnoment variable in the default or embedded environment.
32012598090bSJoe Hershberger
32022598090bSJoe Hershberger	- CONFIG_ENV_FLAGS_LIST_STATIC
32032598090bSJoe Hershberger		Define this to a list (string) to define validation that
32042598090bSJoe Hershberger		should be done if an entry is not found in the ".flags"
32052598090bSJoe Hershberger		environment variable.  To override a setting in the static
32062598090bSJoe Hershberger		list, simply add an entry for the same variable name to the
32072598090bSJoe Hershberger		".flags" variable.
32082598090bSJoe Hershberger
3209267541f7SJoe Hershberger- CONFIG_ENV_ACCESS_IGNORE_FORCE
3210267541f7SJoe Hershberger	If defined, don't allow the -f switch to env set override variable
3211267541f7SJoe Hershberger	access flags.
3212267541f7SJoe Hershberger
3213c609719bSwdenkThe following definitions that deal with the placement and management
3214c609719bSwdenkof environment data (variable area); in general, we support the
3215c609719bSwdenkfollowing configurations:
3216c609719bSwdenk
3217c3eb3fe4SMike Frysinger- CONFIG_BUILD_ENVCRC:
3218c3eb3fe4SMike Frysinger
3219c3eb3fe4SMike Frysinger	Builds up envcrc with the target environment so that external utils
3220c3eb3fe4SMike Frysinger	may easily extract it and embed it in final U-Boot images.
3221c3eb3fe4SMike Frysinger
32225a1aceb0SJean-Christophe PLAGNIOL-VILLARD- CONFIG_ENV_IS_IN_FLASH:
3223c609719bSwdenk
3224c609719bSwdenk	Define this if the environment is in flash memory.
3225c609719bSwdenk
3226c609719bSwdenk	a) The environment occupies one whole flash sector, which is
3227c609719bSwdenk	   "embedded" in the text segment with the U-Boot code. This
3228c609719bSwdenk	   happens usually with "bottom boot sector" or "top boot
3229c609719bSwdenk	   sector" type flash chips, which have several smaller
3230c609719bSwdenk	   sectors at the start or the end. For instance, such a
3231c609719bSwdenk	   layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3232c609719bSwdenk	   such a case you would place the environment in one of the
3233c609719bSwdenk	   4 kB sectors - with U-Boot code before and after it. With
3234c609719bSwdenk	   "top boot sector" type flash chips, you would put the
3235c609719bSwdenk	   environment in one of the last sectors, leaving a gap
3236c609719bSwdenk	   between U-Boot and the environment.
3237c609719bSwdenk
32380e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_OFFSET:
3239c609719bSwdenk
3240c609719bSwdenk	   Offset of environment data (variable area) to the
3241c609719bSwdenk	   beginning of flash memory; for instance, with bottom boot
3242c609719bSwdenk	   type flash chips the second sector can be used: the offset
3243c609719bSwdenk	   for this sector is given here.
3244c609719bSwdenk
32456d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	   CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3246c609719bSwdenk
32470e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_ADDR:
3248c609719bSwdenk
3249c609719bSwdenk	   This is just another way to specify the start address of
3250c609719bSwdenk	   the flash sector containing the environment (instead of
32510e8d1586SJean-Christophe PLAGNIOL-VILLARD	   CONFIG_ENV_OFFSET).
3252c609719bSwdenk
32530e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_SECT_SIZE:
3254c609719bSwdenk
3255c609719bSwdenk	   Size of the sector containing the environment.
3256c609719bSwdenk
3257c609719bSwdenk
3258c609719bSwdenk	b) Sometimes flash chips have few, equal sized, BIG sectors.
3259c609719bSwdenk	   In such a case you don't want to spend a whole sector for
3260c609719bSwdenk	   the environment.
3261c609719bSwdenk
32620e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_SIZE:
3263c609719bSwdenk
32645a1aceb0SJean-Christophe PLAGNIOL-VILLARD	   If you use this in combination with CONFIG_ENV_IS_IN_FLASH
32650e8d1586SJean-Christophe PLAGNIOL-VILLARD	   and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3266c609719bSwdenk	   of this flash sector for the environment. This saves
3267c609719bSwdenk	   memory for the RAM copy of the environment.
3268c609719bSwdenk
3269c609719bSwdenk	   It may also save flash memory if you decide to use this
3270c609719bSwdenk	   when your environment is "embedded" within U-Boot code,
3271c609719bSwdenk	   since then the remainder of the flash sector could be used
3272c609719bSwdenk	   for U-Boot code. It should be pointed out that this is
3273c609719bSwdenk	   STRONGLY DISCOURAGED from a robustness point of view:
3274c609719bSwdenk	   updating the environment in flash makes it always
3275c609719bSwdenk	   necessary to erase the WHOLE sector. If something goes
3276c609719bSwdenk	   wrong before the contents has been restored from a copy in
3277c609719bSwdenk	   RAM, your target system will be dead.
3278c609719bSwdenk
32790e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_ADDR_REDUND
32800e8d1586SJean-Christophe PLAGNIOL-VILLARD	  CONFIG_ENV_SIZE_REDUND
3281c609719bSwdenk
3282c609719bSwdenk	   These settings describe a second storage area used to hold
328311ccc33fSMarcel Ziswiler	   a redundant copy of the environment data, so that there is
32843e38691eSwdenk	   a valid backup copy in case there is a power failure during
3285c609719bSwdenk	   a "saveenv" operation.
3286c609719bSwdenk
3287c609719bSwdenkBE CAREFUL! Any changes to the flash layout, and some changes to the
3288c609719bSwdenksource code will make it necessary to adapt <board>/u-boot.lds*
3289c609719bSwdenkaccordingly!
3290c609719bSwdenk
3291c609719bSwdenk
32929314cee6SJean-Christophe PLAGNIOL-VILLARD- CONFIG_ENV_IS_IN_NVRAM:
3293c609719bSwdenk
3294c609719bSwdenk	Define this if you have some non-volatile memory device
3295c609719bSwdenk	(NVRAM, battery buffered SRAM) which you want to use for the
3296c609719bSwdenk	environment.
3297c609719bSwdenk
32980e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_ADDR:
32990e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_SIZE:
3300c609719bSwdenk
330111ccc33fSMarcel Ziswiler	  These two #defines are used to determine the memory area you
3302c609719bSwdenk	  want to use for environment. It is assumed that this memory
3303c609719bSwdenk	  can just be read and written to, without any special
3304c609719bSwdenk	  provision.
3305c609719bSwdenk
3306c609719bSwdenkBE CAREFUL! The first access to the environment happens quite early
3307c609719bSwdenkin U-Boot initalization (when we try to get the setting of for the
330811ccc33fSMarcel Ziswilerconsole baudrate). You *MUST* have mapped your NVRAM area then, or
3309c609719bSwdenkU-Boot will hang.
3310c609719bSwdenk
3311c609719bSwdenkPlease note that even with NVRAM we still use a copy of the
3312c609719bSwdenkenvironment in RAM: we could work on NVRAM directly, but we want to
3313c609719bSwdenkkeep settings there always unmodified except somebody uses "saveenv"
3314c609719bSwdenkto save the current settings.
3315c609719bSwdenk
3316c609719bSwdenk
3317bb1f8b4fSJean-Christophe PLAGNIOL-VILLARD- CONFIG_ENV_IS_IN_EEPROM:
3318c609719bSwdenk
3319c609719bSwdenk	Use this if you have an EEPROM or similar serial access
3320c609719bSwdenk	device and a driver for it.
3321c609719bSwdenk
33220e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_OFFSET:
33230e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_SIZE:
3324c609719bSwdenk
3325c609719bSwdenk	  These two #defines specify the offset and size of the
3326c609719bSwdenk	  environment area within the total memory of your EEPROM.
3327c609719bSwdenk
33286d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	- CONFIG_SYS_I2C_EEPROM_ADDR:
3329c609719bSwdenk	  If defined, specified the chip address of the EEPROM device.
3330c609719bSwdenk	  The default address is zero.
3331c609719bSwdenk
33326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	- CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3333c609719bSwdenk	  If defined, the number of bits used to address bytes in a
3334c609719bSwdenk	  single page in the EEPROM device.  A 64 byte page, for example
3335c609719bSwdenk	  would require six bits.
3336c609719bSwdenk
33376d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	- CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3338c609719bSwdenk	  If defined, the number of milliseconds to delay between
3339c609719bSwdenk	  page writes.	The default is zero milliseconds.
3340c609719bSwdenk
33416d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	- CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3342c609719bSwdenk	  The length in bytes of the EEPROM memory array address.  Note
3343c609719bSwdenk	  that this is NOT the chip address length!
3344c609719bSwdenk
33456d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	- CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
33465cf91d6bSwdenk	  EEPROM chips that implement "address overflow" are ones
33475cf91d6bSwdenk	  like Catalyst 24WC04/08/16 which has 9/10/11 bits of
33485cf91d6bSwdenk	  address and the extra bits end up in the "chip address" bit
33495cf91d6bSwdenk	  slots. This makes a 24WC08 (1Kbyte) chip look like four 256
33505cf91d6bSwdenk	  byte chips.
33515cf91d6bSwdenk
33525cf91d6bSwdenk	  Note that we consider the length of the address field to
33535cf91d6bSwdenk	  still be one byte because the extra address bits are hidden
33545cf91d6bSwdenk	  in the chip address.
33555cf91d6bSwdenk
33566d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	- CONFIG_SYS_EEPROM_SIZE:
3357c609719bSwdenk	  The size in bytes of the EEPROM device.
3358c609719bSwdenk
3359548738b4SHeiko Schocher	- CONFIG_ENV_EEPROM_IS_ON_I2C
3360548738b4SHeiko Schocher	  define this, if you have I2C and SPI activated, and your
3361548738b4SHeiko Schocher	  EEPROM, which holds the environment, is on the I2C bus.
3362548738b4SHeiko Schocher
3363548738b4SHeiko Schocher	- CONFIG_I2C_ENV_EEPROM_BUS
3364548738b4SHeiko Schocher	  if you have an Environment on an EEPROM reached over
3365548738b4SHeiko Schocher	  I2C muxes, you can define here, how to reach this
3366548738b4SHeiko Schocher	  EEPROM. For example:
3367548738b4SHeiko Schocher
3368548738b4SHeiko Schocher	  #define CONFIG_I2C_ENV_EEPROM_BUS	  "pca9547:70:d\0"
3369548738b4SHeiko Schocher
3370548738b4SHeiko Schocher	  EEPROM which holds the environment, is reached over
3371548738b4SHeiko Schocher	  a pca9547 i2c mux with address 0x70, channel 3.
3372c609719bSwdenk
3373057c849cSJean-Christophe PLAGNIOL-VILLARD- CONFIG_ENV_IS_IN_DATAFLASH:
33745779d8d9Swdenk
33755779d8d9Swdenk	Define this if you have a DataFlash memory device which you
33765779d8d9Swdenk	want to use for the environment.
33775779d8d9Swdenk
33780e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_OFFSET:
33790e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_ADDR:
33800e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_SIZE:
33815779d8d9Swdenk
33825779d8d9Swdenk	  These three #defines specify the offset and size of the
33835779d8d9Swdenk	  environment area within the total memory of your DataFlash placed
33845779d8d9Swdenk	  at the specified address.
33855779d8d9Swdenk
33860a85a9e7SLiu Gang- CONFIG_ENV_IS_IN_REMOTE:
33870a85a9e7SLiu Gang
33880a85a9e7SLiu Gang	Define this if you have a remote memory space which you
33890a85a9e7SLiu Gang	want to use for the local device's environment.
33900a85a9e7SLiu Gang
33910a85a9e7SLiu Gang	- CONFIG_ENV_ADDR:
33920a85a9e7SLiu Gang	- CONFIG_ENV_SIZE:
33930a85a9e7SLiu Gang
33940a85a9e7SLiu Gang	  These two #defines specify the address and size of the
33950a85a9e7SLiu Gang	  environment area within the remote memory space. The
33960a85a9e7SLiu Gang	  local device can get the environment from remote memory
3397fc54c7faSLiu Gang	  space by SRIO or PCIE links.
33980a85a9e7SLiu Gang
33990a85a9e7SLiu GangBE CAREFUL! For some special cases, the local device can not use
34000a85a9e7SLiu Gang"saveenv" command. For example, the local device will get the
3401fc54c7faSLiu Gangenvironment stored in a remote NOR flash by SRIO or PCIE link,
3402fc54c7faSLiu Gangbut it can not erase, write this NOR flash by SRIO or PCIE interface.
34030a85a9e7SLiu Gang
340451bfee19SJean-Christophe PLAGNIOL-VILLARD- CONFIG_ENV_IS_IN_NAND:
340513a5695bSwdenk
340613a5695bSwdenk	Define this if you have a NAND device which you want to use
340713a5695bSwdenk	for the environment.
340813a5695bSwdenk
34090e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_OFFSET:
34100e8d1586SJean-Christophe PLAGNIOL-VILLARD	- CONFIG_ENV_SIZE:
341113a5695bSwdenk
341213a5695bSwdenk	  These two #defines specify the offset and size of the environment
3413fdd813deSScott Wood	  area within the first NAND device.  CONFIG_ENV_OFFSET must be
3414fdd813deSScott Wood	  aligned to an erase block boundary.
34155779d8d9Swdenk
3416fdd813deSScott Wood	- CONFIG_ENV_OFFSET_REDUND (optional):
3417e443c944SMarkus Klotzbuecher
34180e8d1586SJean-Christophe PLAGNIOL-VILLARD	  This setting describes a second storage area of CONFIG_ENV_SIZE
3419fdd813deSScott Wood	  size used to hold a redundant copy of the environment data, so
3420fdd813deSScott Wood	  that there is a valid backup copy in case there is a power failure
3421fdd813deSScott Wood	  during a "saveenv" operation.	 CONFIG_ENV_OFFSET_RENDUND must be
3422fdd813deSScott Wood	  aligned to an erase block boundary.
3423e443c944SMarkus Klotzbuecher
3424fdd813deSScott Wood	- CONFIG_ENV_RANGE (optional):
3425fdd813deSScott Wood
3426fdd813deSScott Wood	  Specifies the length of the region in which the environment
3427fdd813deSScott Wood	  can be written.  This should be a multiple of the NAND device's
3428fdd813deSScott Wood	  block size.  Specifying a range with more erase blocks than
3429fdd813deSScott Wood	  are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3430fdd813deSScott Wood	  the range to be avoided.
3431fdd813deSScott Wood
3432fdd813deSScott Wood	- CONFIG_ENV_OFFSET_OOB (optional):
3433fdd813deSScott Wood
3434fdd813deSScott Wood	  Enables support for dynamically retrieving the offset of the
3435fdd813deSScott Wood	  environment from block zero's out-of-band data.  The
3436fdd813deSScott Wood	  "nand env.oob" command can be used to record this offset.
3437fdd813deSScott Wood	  Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3438fdd813deSScott Wood	  using CONFIG_ENV_OFFSET_OOB.
3439e443c944SMarkus Klotzbuecher
3440b74ab737SGuennadi Liakhovetski- CONFIG_NAND_ENV_DST
3441b74ab737SGuennadi Liakhovetski
3442b74ab737SGuennadi Liakhovetski	Defines address in RAM to which the nand_spl code should copy the
3443b74ab737SGuennadi Liakhovetski	environment. If redundant environment is used, it will be copied to
3444b74ab737SGuennadi Liakhovetski	CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3445b74ab737SGuennadi Liakhovetski
34466d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SPI_INIT_OFFSET
3447c609719bSwdenk
3448c609719bSwdenk	Defines offset to the initial SPI buffer area in DPRAM. The
3449c609719bSwdenk	area is used at an early stage (ROM part) if the environment
3450c609719bSwdenk	is configured to reside in the SPI EEPROM: We need a 520 byte
3451c609719bSwdenk	scratch DPRAM area. It is used between the two initialization
3452c609719bSwdenk	calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3453c609719bSwdenk	to be a good choice since it makes it far enough from the
3454c609719bSwdenk	start of the data area as well as from the stack pointer.
3455c609719bSwdenk
3456e881cb56SBruce AdlerPlease note that the environment is read-only until the monitor
3457c609719bSwdenkhas been relocated to RAM and a RAM copy of the environment has been
3458cdb74977SWolfgang Denkcreated; also, when using EEPROM you will have to use getenv_f()
3459c609719bSwdenkuntil then to read environment variables.
3460c609719bSwdenk
346185ec0bccSwdenkThe environment is protected by a CRC32 checksum. Before the monitor
346285ec0bccSwdenkis relocated into RAM, as a result of a bad CRC you will be working
346385ec0bccSwdenkwith the compiled-in default environment - *silently*!!! [This is
346485ec0bccSwdenknecessary, because the first environment variable we need is the
346585ec0bccSwdenk"baudrate" setting for the console - if we have a bad CRC, we don't
346685ec0bccSwdenkhave any device yet where we could complain.]
3467c609719bSwdenk
3468c609719bSwdenkNote: once the monitor has been relocated, then it will complain if
3469c609719bSwdenkthe default environment is used; a new CRC is computed as soon as you
347085ec0bccSwdenkuse the "saveenv" command to store a valid environment.
3471c609719bSwdenk
34726d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3473fc3e2165Swdenk		Echo the inverted Ethernet link state to the fault LED.
3474fc3e2165Swdenk
34756d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3476fc3e2165Swdenk		      also needs to be defined.
3477fc3e2165Swdenk
34786d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_FAULT_MII_ADDR:
3479fc3e2165Swdenk		MII address of the PHY to check for the Ethernet link state.
3480c609719bSwdenk
3481f5675aa5SRon Madrid- CONFIG_NS16550_MIN_FUNCTIONS:
3482f5675aa5SRon Madrid		Define this if you desire to only have use of the NS16550_init
3483f5675aa5SRon Madrid		and NS16550_putc functions for the serial driver located at
3484f5675aa5SRon Madrid		drivers/serial/ns16550.c.  This option is useful for saving
3485f5675aa5SRon Madrid		space for already greatly restricted images, including but not
3486f5675aa5SRon Madrid		limited to NAND_SPL configurations.
3487f5675aa5SRon Madrid
3488b2b92f53SSimon Glass- CONFIG_DISPLAY_BOARDINFO
3489b2b92f53SSimon Glass		Display information about the board that U-Boot is running on
3490b2b92f53SSimon Glass		when U-Boot starts up. The board function checkboard() is called
3491b2b92f53SSimon Glass		to do this.
3492b2b92f53SSimon Glass
3493e2e3e2b1SSimon Glass- CONFIG_DISPLAY_BOARDINFO_LATE
3494e2e3e2b1SSimon Glass		Similar to the previous option, but display this information
3495e2e3e2b1SSimon Glass		later, once stdio is running and output goes to the LCD, if
3496e2e3e2b1SSimon Glass		present.
3497e2e3e2b1SSimon Glass
3498c609719bSwdenkLow Level (hardware related) configuration options:
3499dc7c9a1aSwdenk---------------------------------------------------
3500c609719bSwdenk
35016d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CACHELINE_SIZE:
3502c609719bSwdenk		Cache Line Size of the CPU.
3503c609719bSwdenk
35046d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_DEFAULT_IMMR:
3505c609719bSwdenk		Default address of the IMMR after system reset.
35062535d602Swdenk
35072535d602Swdenk		Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
35082535d602Swdenk		and RPXsuper) to be able to adjust the position of
35092535d602Swdenk		the IMMR register after a reset.
3510c609719bSwdenk
3511e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_DEFAULT:
3512e46fedfeSTimur Tabi		Default (power-on reset) physical address of CCSR on Freescale
3513e46fedfeSTimur Tabi		PowerPC SOCs.
3514e46fedfeSTimur Tabi
3515e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR:
3516e46fedfeSTimur Tabi		Virtual address of CCSR.  On a 32-bit build, this is typically
3517e46fedfeSTimur Tabi		the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3518e46fedfeSTimur Tabi
3519e46fedfeSTimur Tabi		CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3520e46fedfeSTimur Tabi		for cross-platform code that uses that macro instead.
3521e46fedfeSTimur Tabi
3522e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS:
3523e46fedfeSTimur Tabi		Physical address of CCSR.  CCSR can be relocated to a new
3524e46fedfeSTimur Tabi		physical address, if desired.  In this case, this macro should
3525e46fedfeSTimur Tabi		be set to that address.	 Otherwise, it should be set to the
3526e46fedfeSTimur Tabi		same value as CONFIG_SYS_CCSRBAR_DEFAULT.  For example, CCSR
3527e46fedfeSTimur Tabi		is typically relocated on 36-bit builds.  It is recommended
3528e46fedfeSTimur Tabi		that this macro be defined via the _HIGH and _LOW macros:
3529e46fedfeSTimur Tabi
3530e46fedfeSTimur Tabi		#define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3531e46fedfeSTimur Tabi			* 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3532e46fedfeSTimur Tabi
3533e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3534e46fedfeSTimur Tabi		Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS.	This value is typically
3535e46fedfeSTimur Tabi		either 0 (32-bit build) or 0xF (36-bit build).	This macro is
3536e46fedfeSTimur Tabi		used in assembly code, so it must not contain typecasts or
3537e46fedfeSTimur Tabi		integer size suffixes (e.g. "ULL").
3538e46fedfeSTimur Tabi
3539e46fedfeSTimur Tabi- CONFIG_SYS_CCSRBAR_PHYS_LOW:
3540e46fedfeSTimur Tabi		Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS.  This macro is
3541e46fedfeSTimur Tabi		used in assembly code, so it must not contain typecasts or
3542e46fedfeSTimur Tabi		integer size suffixes (e.g. "ULL").
3543e46fedfeSTimur Tabi
3544e46fedfeSTimur Tabi- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3545e46fedfeSTimur Tabi		If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3546e46fedfeSTimur Tabi		forced to a value that ensures that CCSR is not relocated.
3547e46fedfeSTimur Tabi
35487f6c2cbcSwdenk- Floppy Disk Support:
35496d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FDC_DRIVE_NUMBER
35507f6c2cbcSwdenk
35517f6c2cbcSwdenk		the default drive number (default value 0)
35527f6c2cbcSwdenk
35536d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_ISA_IO_STRIDE
35547f6c2cbcSwdenk
355511ccc33fSMarcel Ziswiler		defines the spacing between FDC chipset registers
35567f6c2cbcSwdenk		(default value 1)
35577f6c2cbcSwdenk
35586d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_ISA_IO_OFFSET
35597f6c2cbcSwdenk
35607f6c2cbcSwdenk		defines the offset of register from address. It
35617f6c2cbcSwdenk		depends on which part of the data bus is connected to
356211ccc33fSMarcel Ziswiler		the FDC chipset. (default value 0)
35637f6c2cbcSwdenk
35646d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
35656d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
35667f6c2cbcSwdenk		default value.
35677f6c2cbcSwdenk
35686d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		if CONFIG_SYS_FDC_HW_INIT is defined, then the function
35697f6c2cbcSwdenk		fdc_hw_init() is called at the beginning of the FDC
35707f6c2cbcSwdenk		setup. fdc_hw_init() must be provided by the board
35717f6c2cbcSwdenk		source code. It is used to make hardware dependant
35727f6c2cbcSwdenk		initializations.
35737f6c2cbcSwdenk
35740abddf82SMacpaul Lin- CONFIG_IDE_AHB:
35750abddf82SMacpaul Lin		Most IDE controllers were designed to be connected with PCI
35760abddf82SMacpaul Lin		interface. Only few of them were designed for AHB interface.
35770abddf82SMacpaul Lin		When software is doing ATA command and data transfer to
35780abddf82SMacpaul Lin		IDE devices through IDE-AHB controller, some additional
35790abddf82SMacpaul Lin		registers accessing to these kind of IDE-AHB controller
35800abddf82SMacpaul Lin		is requierd.
35810abddf82SMacpaul Lin
35826d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_IMMR:	Physical address of the Internal Memory.
358325d6712aSwdenk		DO NOT CHANGE unless you know exactly what you're
358425d6712aSwdenk		doing! (11-4) [MPC8xx/82xx systems only]
3585c609719bSwdenk
35866d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_INIT_RAM_ADDR:
3587c609719bSwdenk
35887152b1d0Swdenk		Start address of memory area that can be used for
3589c609719bSwdenk		initial data and stack; please note that this must be
3590c609719bSwdenk		writable memory that is working WITHOUT special
3591c609719bSwdenk		initialization, i. e. you CANNOT use normal RAM which
3592c609719bSwdenk		will become available only after programming the
3593c609719bSwdenk		memory controller and running certain initialization
3594c609719bSwdenk		sequences.
3595c609719bSwdenk
3596c609719bSwdenk		U-Boot uses the following memory types:
3597c609719bSwdenk		- MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3598c609719bSwdenk		- MPC824X: data cache
3599c609719bSwdenk		- PPC4xx:  data cache
3600c609719bSwdenk
36016d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_GBL_DATA_OFFSET:
3602c609719bSwdenk
3603c609719bSwdenk		Offset of the initial data structure in the memory
36046d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
36056d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3606c609719bSwdenk		data is located at the end of the available space
3607553f0982SWolfgang Denk		(sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
36086d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
36096d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
36106d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_GBL_DATA_OFFSET) downward.
3611c609719bSwdenk
3612c609719bSwdenk	Note:
3613c609719bSwdenk		On the MPC824X (or other systems that use the data
3614c609719bSwdenk		cache for initial memory) the address chosen for
36156d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3616c609719bSwdenk		point to an otherwise UNUSED address space between
3617c609719bSwdenk		the top of RAM and the start of the PCI space.
3618c609719bSwdenk
36196d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SIUMCR:	SIU Module Configuration (11-6)
3620c609719bSwdenk
36216d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SYPCR:	System Protection Control (11-9)
3622c609719bSwdenk
36236d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_TBSCR:	Time Base Status and Control (11-26)
3624c609719bSwdenk
36256d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PISCR:	Periodic Interrupt Status and Control (11-31)
3626c609719bSwdenk
36276d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PLPRCR:	PLL, Low-Power, and Reset Control Register (15-30)
3628c609719bSwdenk
36296d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SCCR:	System Clock and reset Control Register (15-27)
3630c609719bSwdenk
36316d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_OR_TIMING_SDRAM:
3632c609719bSwdenk		SDRAM timing
3633c609719bSwdenk
36346d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAMR_PTA:
3635c609719bSwdenk		periodic timer for refresh
3636c609719bSwdenk
36376d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_DER:	Debug Event Register (37-47)
3638c609719bSwdenk
36396d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
36406d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
36416d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
36426d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_BR1_PRELIM:
3643c609719bSwdenk		Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3644c609719bSwdenk
3645c609719bSwdenk- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
36466d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
36476d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3648c609719bSwdenk		Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3649c609719bSwdenk
36506d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
36516d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3652c609719bSwdenk		Machine Mode Register and Memory Periodic Timer
3653c609719bSwdenk		Prescaler definitions (SDRAM timing)
3654c609719bSwdenk
36556d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3656c609719bSwdenk		enable I2C microcode relocation patch (MPC8xx);
3657c609719bSwdenk		define relocation offset in DPRAM [DSP2]
3658c609719bSwdenk
36596d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3660b423d055SHeiko Schocher		enable SMC microcode relocation patch (MPC8xx);
3661b423d055SHeiko Schocher		define relocation offset in DPRAM [SMC1]
3662b423d055SHeiko Schocher
36636d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3664c609719bSwdenk		enable SPI microcode relocation patch (MPC8xx);
3665c609719bSwdenk		define relocation offset in DPRAM [SCC4]
3666c609719bSwdenk
36676d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_USE_OSCCLK:
3668c609719bSwdenk		Use OSCM clock mode on MBX8xx board. Be careful,
3669c609719bSwdenk		wrong setting might damage your board. Read
3670c609719bSwdenk		doc/README.MBX before setting this variable!
3671c609719bSwdenk
36726d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3673ea909b76Swdenk		Offset of the bootmode word in DPRAM used by post
3674ea909b76Swdenk		(Power On Self Tests). This definition overrides
3675ea909b76Swdenk		#define'd default value in commproc.h resp.
3676ea909b76Swdenk		cpm_8260.h.
3677ea909b76Swdenk
36786d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
36796d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
36806d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
36816d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
36826d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
36836d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
36846d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
36856d0f6bcfSJean-Christophe PLAGNIOL-VILLARD  CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
3686a47a12beSStefan Roese		Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
36875d232d0eSwdenk
36889cacf4fcSDirk Eibach- CONFIG_PCI_DISABLE_PCIE:
36899cacf4fcSDirk Eibach		Disable PCI-Express on systems where it is supported but not
36909cacf4fcSDirk Eibach		required.
36919cacf4fcSDirk Eibach
369269fd2d3bSAndrew Sharp- CONFIG_PCI_ENUM_ONLY
369369fd2d3bSAndrew Sharp		Only scan through and get the devices on the busses.
369469fd2d3bSAndrew Sharp		Don't do any setup work, presumably because someone or
369569fd2d3bSAndrew Sharp		something has already done it, and we don't need to do it
369669fd2d3bSAndrew Sharp		a second time.	Useful for platforms that are pre-booted
369769fd2d3bSAndrew Sharp		by coreboot or similar.
369869fd2d3bSAndrew Sharp
3699a09b9b68SKumar Gala- CONFIG_SYS_SRIO:
3700a09b9b68SKumar Gala		Chip has SRIO or not
3701a09b9b68SKumar Gala
3702a09b9b68SKumar Gala- CONFIG_SRIO1:
3703a09b9b68SKumar Gala		Board has SRIO 1 port available
3704a09b9b68SKumar Gala
3705a09b9b68SKumar Gala- CONFIG_SRIO2:
3706a09b9b68SKumar Gala		Board has SRIO 2 port available
3707a09b9b68SKumar Gala
3708a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_VIRT:
3709a09b9b68SKumar Gala		Virtual Address of SRIO port 'n' memory region
3710a09b9b68SKumar Gala
3711a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_PHYS:
3712a09b9b68SKumar Gala		Physical Address of SRIO port 'n' memory region
3713a09b9b68SKumar Gala
3714a09b9b68SKumar Gala- CONFIG_SYS_SRIOn_MEM_SIZE:
3715a09b9b68SKumar Gala		Size of SRIO port 'n' memory region
3716a09b9b68SKumar Gala
3717eced4626SAlex Waterman- CONFIG_SYS_NDFC_16
3718eced4626SAlex Waterman		Defined to tell the NDFC that the NAND chip is using a
3719eced4626SAlex Waterman		16 bit bus.
3720eced4626SAlex Waterman
3721eced4626SAlex Waterman- CONFIG_SYS_NDFC_EBC0_CFG
3722eced4626SAlex Waterman		Sets the EBC0_CFG register for the NDFC. If not defined
3723eced4626SAlex Waterman		a default value will be used.
3724eced4626SAlex Waterman
3725bb99ad6dSBen Warren- CONFIG_SPD_EEPROM
3726218ca724SWolfgang Denk		Get DDR timing information from an I2C EEPROM. Common
3727218ca724SWolfgang Denk		with pluggable memory modules such as SODIMMs
3728218ca724SWolfgang Denk
3729bb99ad6dSBen Warren  SPD_EEPROM_ADDRESS
3730bb99ad6dSBen Warren		I2C address of the SPD EEPROM
3731bb99ad6dSBen Warren
37326d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_SPD_BUS_NUM
3733218ca724SWolfgang Denk		If SPD EEPROM is on an I2C bus other than the first
3734218ca724SWolfgang Denk		one, specify here. Note that the value must resolve
3735218ca724SWolfgang Denk		to something your driver can deal with.
3736bb99ad6dSBen Warren
37371b3e3c4fSYork Sun- CONFIG_SYS_DDR_RAW_TIMING
37381b3e3c4fSYork Sun		Get DDR timing information from other than SPD. Common with
37391b3e3c4fSYork Sun		soldered DDR chips onboard without SPD. DDR raw timing
37401b3e3c4fSYork Sun		parameters are extracted from datasheet and hard-coded into
37411b3e3c4fSYork Sun		header files or board specific files.
37421b3e3c4fSYork Sun
37436f5e1dc5SYork Sun- CONFIG_FSL_DDR_INTERACTIVE
37446f5e1dc5SYork Sun		Enable interactive DDR debugging. See doc/README.fsl-ddr.
37456f5e1dc5SYork Sun
37466d0f6bcfSJean-Christophe PLAGNIOL-VILLARD- CONFIG_SYS_83XX_DDR_USES_CS0
3747218ca724SWolfgang Denk		Only for 83xx systems. If specified, then DDR should
3748218ca724SWolfgang Denk		be configured using CS0 and CS1 instead of CS2 and CS3.
37492ad6b513STimur Tabi
3750c26e454dSwdenk- CONFIG_ETHER_ON_FEC[12]
3751c26e454dSwdenk		Define to enable FEC[12] on a 8xx series processor.
3752c26e454dSwdenk
3753c26e454dSwdenk- CONFIG_FEC[12]_PHY
3754c26e454dSwdenk		Define to the hardcoded PHY address which corresponds
37556e592385Swdenk		to the given FEC; i. e.
3756c26e454dSwdenk			#define CONFIG_FEC1_PHY 4
3757c26e454dSwdenk		means that the PHY with address 4 is connected to FEC1
3758c26e454dSwdenk
3759c26e454dSwdenk		When set to -1, means to probe for first available.
3760c26e454dSwdenk
3761c26e454dSwdenk- CONFIG_FEC[12]_PHY_NORXERR
3762c26e454dSwdenk		The PHY does not have a RXERR line (RMII only).
3763c26e454dSwdenk		(so program the FEC to ignore it).
3764c26e454dSwdenk
3765c26e454dSwdenk- CONFIG_RMII
3766c26e454dSwdenk		Enable RMII mode for all FECs.
3767c26e454dSwdenk		Note that this is a global option, we can't
3768c26e454dSwdenk		have one FEC in standard MII mode and another in RMII mode.
3769c26e454dSwdenk
37705cf91d6bSwdenk- CONFIG_CRC32_VERIFY
37715cf91d6bSwdenk		Add a verify option to the crc32 command.
37725cf91d6bSwdenk		The syntax is:
37735cf91d6bSwdenk
37745cf91d6bSwdenk		=> crc32 -v <address> <count> <crc32>
37755cf91d6bSwdenk
37765cf91d6bSwdenk		Where address/count indicate a memory area
37775cf91d6bSwdenk		and crc32 is the correct crc32 which the
37785cf91d6bSwdenk		area should have.
37795cf91d6bSwdenk
378056523f12Swdenk- CONFIG_LOOPW
378156523f12Swdenk		Add the "loopw" memory command. This only takes effect if
3782602ad3b3SJon Loeliger		the memory commands are activated globally (CONFIG_CMD_MEM).
378356523f12Swdenk
37847b466641Sstroese- CONFIG_MX_CYCLIC
37857b466641Sstroese		Add the "mdc" and "mwc" memory commands. These are cyclic
37867b466641Sstroese		"md/mw" commands.
37877b466641Sstroese		Examples:
37887b466641Sstroese
37897b466641Sstroese		=> mdc.b 10 4 500
37907b466641Sstroese		This command will print 4 bytes (10,11,12,13) each 500 ms.
37917b466641Sstroese
37927b466641Sstroese		=> mwc.l 100 12345678 10
37937b466641Sstroese		This command will write 12345678 to address 100 all 10 ms.
37947b466641Sstroese
37957b466641Sstroese		This only takes effect if the memory commands are activated
3796602ad3b3SJon Loeliger		globally (CONFIG_CMD_MEM).
37977b466641Sstroese
37988aa1a2d1Swdenk- CONFIG_SKIP_LOWLEVEL_INIT
3799afc1ce82SMacpaul Lin		[ARM, NDS32, MIPS only] If this variable is defined, then certain
3800e03f3169SWolfgang Denk		low level initializations (like setting up the memory
3801e03f3169SWolfgang Denk		controller) are omitted and/or U-Boot does not
3802e03f3169SWolfgang Denk		relocate itself into RAM.
38038aa1a2d1Swdenk
3804e03f3169SWolfgang Denk		Normally this variable MUST NOT be defined. The only
3805e03f3169SWolfgang Denk		exception is when U-Boot is loaded (to RAM) by some
3806e03f3169SWolfgang Denk		other boot loader or by a debugger which performs
3807e03f3169SWolfgang Denk		these initializations itself.
38088aa1a2d1Swdenk
3809401bb30bSAneesh V- CONFIG_SPL_BUILD
3810df81238bSMagnus Lilja		Modifies the behaviour of start.S when compiling a loader
3811df81238bSMagnus Lilja		that is executed before the actual U-Boot. E.g. when
3812df81238bSMagnus Lilja		compiling a NAND SPL.
3813400558b5Swdenk
3814d8834a13SMatthias Weisser- CONFIG_USE_ARCH_MEMCPY
3815d8834a13SMatthias Weisser  CONFIG_USE_ARCH_MEMSET
3816d8834a13SMatthias Weisser		If these options are used a optimized version of memcpy/memset will
3817d8834a13SMatthias Weisser		be used if available. These functions may be faster under some
3818d8834a13SMatthias Weisser		conditions but may increase the binary size.
3819d8834a13SMatthias Weisser
3820588a13f7SSimon Glass- CONFIG_X86_RESET_VECTOR
3821588a13f7SSimon Glass		If defined, the x86 reset vector code is included. This is not
3822588a13f7SSimon Glass		needed when U-Boot is running from Coreboot.
3823b16f521aSGabe Black
38245b5ece9eSGabe Black
3825f2717b47STimur TabiFreescale QE/FMAN Firmware Support:
3826f2717b47STimur Tabi-----------------------------------
3827f2717b47STimur Tabi
3828f2717b47STimur TabiThe Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3829f2717b47STimur Tabiloading of "firmware", which is encoded in the QE firmware binary format.
3830f2717b47STimur TabiThis firmware often needs to be loaded during U-Boot booting, so macros
3831f2717b47STimur Tabiare used to identify the storage device (NOR flash, SPI, etc) and the address
3832f2717b47STimur Tabiwithin that device.
3833f2717b47STimur Tabi
3834f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_ADDR
3835f2717b47STimur Tabi	The address in the storage device where the firmware is located.  The
3836f2717b47STimur Tabi	meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3837f2717b47STimur Tabi	is also specified.
3838f2717b47STimur Tabi
3839f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_LENGTH
3840f2717b47STimur Tabi	The maximum possible size of the firmware.  The firmware binary format
3841f2717b47STimur Tabi	has a field that specifies the actual size of the firmware, but it
3842f2717b47STimur Tabi	might not be possible to read any part of the firmware unless some
3843f2717b47STimur Tabi	local storage is allocated to hold the entire firmware first.
3844f2717b47STimur Tabi
3845f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3846f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3847f2717b47STimur Tabi	normal addressable memory via the LBC.  CONFIG_SYS_FMAN_FW_ADDR is the
3848f2717b47STimur Tabi	virtual address in NOR flash.
3849f2717b47STimur Tabi
3850f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3851f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located in NAND flash.
3852f2717b47STimur Tabi	CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3853f2717b47STimur Tabi
3854f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3855f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located on the primary SD/MMC
3856f2717b47STimur Tabi	device.  CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3857f2717b47STimur Tabi
3858f2717b47STimur Tabi- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
3859f2717b47STimur Tabi	Specifies that QE/FMAN firmware is located on the primary SPI
3860f2717b47STimur Tabi	device.  CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3861f2717b47STimur Tabi
3862292dc6c5SLiu Gang- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3863292dc6c5SLiu Gang	Specifies that QE/FMAN firmware is located in the remote (master)
3864292dc6c5SLiu Gang	memory space.	CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
3865fc54c7faSLiu Gang	can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3866fc54c7faSLiu Gang	window->master inbound window->master LAW->the ucode address in
3867fc54c7faSLiu Gang	master's memory space.
3868f2717b47STimur Tabi
3869c609719bSwdenkBuilding the Software:
3870c609719bSwdenk======================
3871c609719bSwdenk
3872218ca724SWolfgang DenkBuilding U-Boot has been tested in several native build environments
3873218ca724SWolfgang Denkand in many different cross environments. Of course we cannot support
3874218ca724SWolfgang Denkall possibly existing versions of cross development tools in all
3875218ca724SWolfgang Denk(potentially obsolete) versions. In case of tool chain problems we
3876218ca724SWolfgang Denkrecommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3877218ca724SWolfgang Denkwhich is extensively used to build and test U-Boot.
3878c609719bSwdenk
3879218ca724SWolfgang DenkIf you are not using a native environment, it is assumed that you
3880218ca724SWolfgang Denkhave GNU cross compiling tools available in your path. In this case,
3881218ca724SWolfgang Denkyou must set the environment variable CROSS_COMPILE in your shell.
3882218ca724SWolfgang DenkNote that no changes to the Makefile or any other source files are
3883218ca724SWolfgang Denknecessary. For example using the ELDK on a 4xx CPU, please enter:
3884c609719bSwdenk
3885218ca724SWolfgang Denk	$ CROSS_COMPILE=ppc_4xx-
3886218ca724SWolfgang Denk	$ export CROSS_COMPILE
3887c609719bSwdenk
38882f8d396bSPeter TyserNote: If you wish to generate Windows versions of the utilities in
38892f8d396bSPeter Tyser      the tools directory you can use the MinGW toolchain
38902f8d396bSPeter Tyser      (http://www.mingw.org).  Set your HOST tools to the MinGW
38912f8d396bSPeter Tyser      toolchain and execute 'make tools'.  For example:
38922f8d396bSPeter Tyser
38932f8d396bSPeter Tyser       $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
38942f8d396bSPeter Tyser
38952f8d396bSPeter Tyser      Binaries such as tools/mkimage.exe will be created which can
38962f8d396bSPeter Tyser      be executed on computers running Windows.
38972f8d396bSPeter Tyser
3898c609719bSwdenkU-Boot is intended to be simple to build. After installing the
3899c609719bSwdenksources you must configure U-Boot for one specific board type. This
3900c609719bSwdenkis done by typing:
3901c609719bSwdenk
3902c609719bSwdenk	make NAME_config
3903c609719bSwdenk
3904218ca724SWolfgang Denkwhere "NAME_config" is the name of one of the existing configu-
39054d675ae6SMichael Jonesrations; see boards.cfg for supported names.
390654387ac9Swdenk
3907c609719bSwdenkNote: for some board special configuration names may exist; check if
3908c609719bSwdenk      additional information is available from the board vendor; for
39092729af9dSwdenk      instance, the TQM823L systems are available without (standard)
39102729af9dSwdenk      or with LCD support. You can select such additional "features"
391111ccc33fSMarcel Ziswiler      when choosing the configuration, i. e.
3912c609719bSwdenk
39132729af9dSwdenk      make TQM823L_config
39142729af9dSwdenk	- will configure for a plain TQM823L, i. e. no LCD support
3915c609719bSwdenk
3916c609719bSwdenk      make TQM823L_LCD_config
3917c609719bSwdenk	- will configure for a TQM823L with U-Boot console on LCD
3918c609719bSwdenk
3919c609719bSwdenk      etc.
3920c609719bSwdenk
3921c609719bSwdenk
3922c609719bSwdenkFinally, type "make all", and you should get some working U-Boot
39237152b1d0Swdenkimages ready for download to / installation on your system:
3924c609719bSwdenk
3925c609719bSwdenk- "u-boot.bin" is a raw binary image
3926c609719bSwdenk- "u-boot" is an image in ELF binary format
3927c609719bSwdenk- "u-boot.srec" is in Motorola S-Record format
3928c609719bSwdenk
3929baf31249SMarian BalakowiczBy default the build is performed locally and the objects are saved
3930baf31249SMarian Balakowiczin the source directory. One of the two methods can be used to change
3931baf31249SMarian Balakowiczthis behavior and build U-Boot to some external directory:
3932baf31249SMarian Balakowicz
3933baf31249SMarian Balakowicz1. Add O= to the make command line invocations:
3934baf31249SMarian Balakowicz
3935baf31249SMarian Balakowicz	make O=/tmp/build distclean
3936baf31249SMarian Balakowicz	make O=/tmp/build NAME_config
3937baf31249SMarian Balakowicz	make O=/tmp/build all
3938baf31249SMarian Balakowicz
3939baf31249SMarian Balakowicz2. Set environment variable BUILD_DIR to point to the desired location:
3940baf31249SMarian Balakowicz
3941baf31249SMarian Balakowicz	export BUILD_DIR=/tmp/build
3942baf31249SMarian Balakowicz	make distclean
3943baf31249SMarian Balakowicz	make NAME_config
3944baf31249SMarian Balakowicz	make all
3945baf31249SMarian Balakowicz
3946baf31249SMarian BalakowiczNote that the command line "O=" setting overrides the BUILD_DIR environment
3947baf31249SMarian Balakowiczvariable.
3948baf31249SMarian Balakowicz
3949c609719bSwdenk
3950c609719bSwdenkPlease be aware that the Makefiles assume you are using GNU make, so
3951c609719bSwdenkfor instance on NetBSD you might need to use "gmake" instead of
3952c609719bSwdenknative "make".
3953c609719bSwdenk
3954c609719bSwdenk
3955c609719bSwdenkIf the system board that you have is not listed, then you will need
3956c609719bSwdenkto port U-Boot to your hardware platform. To do this, follow these
3957c609719bSwdenksteps:
3958c609719bSwdenk
3959c609719bSwdenk1.  Add a new configuration option for your board to the toplevel
39604d675ae6SMichael Jones    "boards.cfg" file, using the existing entries as examples.
39614d675ae6SMichael Jones    Follow the instructions there to keep the boards in order.
3962c609719bSwdenk2.  Create a new directory to hold your board specific code. Add any
396385ec0bccSwdenk    files you need. In your board directory, you will need at least
396485ec0bccSwdenk    the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
396585ec0bccSwdenk3.  Create a new configuration file "include/configs/<board>.h" for
396685ec0bccSwdenk    your board
3967c609719bSwdenk3.  If you're porting U-Boot to a new CPU, then also create a new
3968c609719bSwdenk    directory to hold your CPU specific code. Add any files you need.
396985ec0bccSwdenk4.  Run "make <board>_config" with your new name.
3970c609719bSwdenk5.  Type "make", and you should get a working "u-boot.srec" file
3971c609719bSwdenk    to be installed on your target system.
397285ec0bccSwdenk6.  Debug and solve any problems that might arise.
3973c609719bSwdenk    [Of course, this last step is much harder than it sounds.]
3974c609719bSwdenk
3975c609719bSwdenk
3976c609719bSwdenkTesting of U-Boot Modifications, Ports to New Hardware, etc.:
3977c609719bSwdenk==============================================================
3978c609719bSwdenk
3979c609719bSwdenkIf you have modified U-Boot sources (for instance added a new board
3980c609719bSwdenkor support for new devices, a new CPU, etc.) you are expected to
3981c609719bSwdenkprovide feedback to the other developers. The feedback normally takes
3982c609719bSwdenkthe form of a "patch", i. e. a context diff against a certain (latest
3983218ca724SWolfgang Denkofficial or latest in the git repository) version of U-Boot sources.
3984c609719bSwdenk
3985c609719bSwdenkBut before you submit such a patch, please verify that your modifi-
3986c609719bSwdenkcation did not break existing code. At least make sure that *ALL* of
3987c609719bSwdenkthe supported boards compile WITHOUT ANY compiler warnings. To do so,
3988c609719bSwdenkjust run the "MAKEALL" script, which will configure and build U-Boot
3989c609719bSwdenkfor ALL supported system. Be warned, this will take a while. You can
39907152b1d0Swdenkselect which (cross) compiler to use by passing a `CROSS_COMPILE'
3991218ca724SWolfgang Denkenvironment variable to the script, i. e. to use the ELDK cross tools
3992218ca724SWolfgang Denkyou can type
3993c609719bSwdenk
3994c609719bSwdenk	CROSS_COMPILE=ppc_8xx- MAKEALL
3995c609719bSwdenk
3996c609719bSwdenkor to build on a native PowerPC system you can type
3997c609719bSwdenk
3998c609719bSwdenk	CROSS_COMPILE=' ' MAKEALL
3999c609719bSwdenk
4000218ca724SWolfgang DenkWhen using the MAKEALL script, the default behaviour is to build
4001218ca724SWolfgang DenkU-Boot in the source directory. This location can be changed by
4002218ca724SWolfgang Denksetting the BUILD_DIR environment variable. Also, for each target
4003218ca724SWolfgang Denkbuilt, the MAKEALL script saves two log files (<target>.ERR and
4004218ca724SWolfgang Denk<target>.MAKEALL) in the <source dir>/LOG directory. This default
4005218ca724SWolfgang Denklocation can be changed by setting the MAKEALL_LOGDIR environment
4006218ca724SWolfgang Denkvariable. For example:
4007baf31249SMarian Balakowicz
4008baf31249SMarian Balakowicz	export BUILD_DIR=/tmp/build
4009baf31249SMarian Balakowicz	export MAKEALL_LOGDIR=/tmp/log
4010baf31249SMarian Balakowicz	CROSS_COMPILE=ppc_8xx- MAKEALL
4011baf31249SMarian Balakowicz
4012218ca724SWolfgang DenkWith the above settings build objects are saved in the /tmp/build,
4013218ca724SWolfgang Denklog files are saved in the /tmp/log and the source tree remains clean
4014218ca724SWolfgang Denkduring the whole build process.
4015baf31249SMarian Balakowicz
4016baf31249SMarian Balakowicz
4017c609719bSwdenkSee also "U-Boot Porting Guide" below.
4018c609719bSwdenk
4019c609719bSwdenk
4020c609719bSwdenkMonitor Commands - Overview:
4021c609719bSwdenk============================
4022c609719bSwdenk
4023c609719bSwdenkgo	- start application at address 'addr'
4024c609719bSwdenkrun	- run commands in an environment variable
4025c609719bSwdenkbootm	- boot application image from memory
4026c609719bSwdenkbootp	- boot image via network using BootP/TFTP protocol
402744f074c7SMarek Vasutbootz   - boot zImage from memory
4028c609719bSwdenktftpboot- boot image via network using TFTP protocol
4029c609719bSwdenk	       and env variables "ipaddr" and "serverip"
4030c609719bSwdenk	       (and eventually "gatewayip")
40311fb7cd49SSimon Glasstftpput - upload a file via network using TFTP protocol
4032c609719bSwdenkrarpboot- boot image via network using RARP/TFTP protocol
4033c609719bSwdenkdiskboot- boot from IDE devicebootd   - boot default, i.e., run 'bootcmd'
4034c609719bSwdenkloads	- load S-Record file over serial line
4035c609719bSwdenkloadb	- load binary file over serial line (kermit mode)
4036c609719bSwdenkmd	- memory display
4037c609719bSwdenkmm	- memory modify (auto-incrementing)
4038c609719bSwdenknm	- memory modify (constant address)
4039c609719bSwdenkmw	- memory write (fill)
4040c609719bSwdenkcp	- memory copy
4041c609719bSwdenkcmp	- memory compare
4042c609719bSwdenkcrc32	- checksum calculation
40430f89c54bSPeter Tyseri2c	- I2C sub-system
4044c609719bSwdenksspi	- SPI utility commands
4045c609719bSwdenkbase	- print or set address offset
4046c609719bSwdenkprintenv- print environment variables
4047c609719bSwdenksetenv	- set environment variables
4048c609719bSwdenksaveenv - save environment variables to persistent storage
4049c609719bSwdenkprotect - enable or disable FLASH write protection
4050c609719bSwdenkerase	- erase FLASH memory
4051c609719bSwdenkflinfo	- print FLASH memory information
405210635afaSKarl O. Pincnand	- NAND memory operations (see doc/README.nand)
4053c609719bSwdenkbdinfo	- print Board Info structure
4054c609719bSwdenkiminfo	- print header information for application image
4055c609719bSwdenkconinfo - print console devices and informations
4056c609719bSwdenkide	- IDE sub-system
4057c609719bSwdenkloop	- infinite loop on address range
405856523f12Swdenkloopw	- infinite write loop on address range
4059c609719bSwdenkmtest	- simple RAM test
4060c609719bSwdenkicache	- enable or disable instruction cache
4061c609719bSwdenkdcache	- enable or disable data cache
4062c609719bSwdenkreset	- Perform RESET of the CPU
4063c609719bSwdenkecho	- echo args to console
4064c609719bSwdenkversion - print monitor version
4065c609719bSwdenkhelp	- print online help
4066c609719bSwdenk?	- alias for 'help'
4067c609719bSwdenk
4068c609719bSwdenk
4069c609719bSwdenkMonitor Commands - Detailed Description:
4070c609719bSwdenk========================================
4071c609719bSwdenk
4072c609719bSwdenkTODO.
4073c609719bSwdenk
4074c609719bSwdenkFor now: just type "help <command>".
4075c609719bSwdenk
4076c609719bSwdenk
4077c609719bSwdenkEnvironment Variables:
4078c609719bSwdenk======================
4079c609719bSwdenk
4080c609719bSwdenkU-Boot supports user configuration using Environment Variables which
4081c609719bSwdenkcan be made persistent by saving to Flash memory.
4082c609719bSwdenk
4083c609719bSwdenkEnvironment Variables are set using "setenv", printed using
4084c609719bSwdenk"printenv", and saved to Flash using "saveenv". Using "setenv"
4085c609719bSwdenkwithout a value can be used to delete a variable from the
4086c609719bSwdenkenvironment. As long as you don't save the environment you are
4087c609719bSwdenkworking with an in-memory copy. In case the Flash area containing the
4088c609719bSwdenkenvironment is erased by accident, a default environment is provided.
4089c609719bSwdenk
4090c96f86eeSWolfgang DenkSome configuration options can be set using Environment Variables.
4091c96f86eeSWolfgang Denk
4092c96f86eeSWolfgang DenkList of environment variables (most likely not complete):
4093c609719bSwdenk
4094c609719bSwdenk  baudrate	- see CONFIG_BAUDRATE
4095c609719bSwdenk
4096c609719bSwdenk  bootdelay	- see CONFIG_BOOTDELAY
4097c609719bSwdenk
4098c609719bSwdenk  bootcmd	- see CONFIG_BOOTCOMMAND
4099c609719bSwdenk
4100c609719bSwdenk  bootargs	- Boot arguments when booting an RTOS image
4101c609719bSwdenk
4102c609719bSwdenk  bootfile	- Name of the image to load with TFTP
4103c609719bSwdenk
41047d721e34SBartlomiej Sieka  bootm_low	- Memory range available for image processing in the bootm
41057d721e34SBartlomiej Sieka		  command can be restricted. This variable is given as
41067d721e34SBartlomiej Sieka		  a hexadecimal number and defines lowest address allowed
41077d721e34SBartlomiej Sieka		  for use by the bootm command. See also "bootm_size"
41087d721e34SBartlomiej Sieka		  environment variable. Address defined by "bootm_low" is
41097d721e34SBartlomiej Sieka		  also the base of the initial memory mapping for the Linux
4110c3624e6eSGrant Likely		  kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4111c3624e6eSGrant Likely		  bootm_mapsize.
4112c3624e6eSGrant Likely
4113c3624e6eSGrant Likely  bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4114c3624e6eSGrant Likely		  This variable is given as a hexadecimal number and it
4115c3624e6eSGrant Likely		  defines the size of the memory region starting at base
4116c3624e6eSGrant Likely		  address bootm_low that is accessible by the Linux kernel
4117c3624e6eSGrant Likely		  during early boot.  If unset, CONFIG_SYS_BOOTMAPSZ is used
4118c3624e6eSGrant Likely		  as the default value if it is defined, and bootm_size is
4119c3624e6eSGrant Likely		  used otherwise.
41207d721e34SBartlomiej Sieka
41217d721e34SBartlomiej Sieka  bootm_size	- Memory range available for image processing in the bootm
41227d721e34SBartlomiej Sieka		  command can be restricted. This variable is given as
41237d721e34SBartlomiej Sieka		  a hexadecimal number and defines the size of the region
41247d721e34SBartlomiej Sieka		  allowed for use by the bootm command. See also "bootm_low"
41257d721e34SBartlomiej Sieka		  environment variable.
41267d721e34SBartlomiej Sieka
41274bae9090SBartlomiej Sieka  updatefile	- Location of the software update file on a TFTP server, used
41284bae9090SBartlomiej Sieka		  by the automatic software update feature. Please refer to
41294bae9090SBartlomiej Sieka		  documentation in doc/README.update for more details.
41304bae9090SBartlomiej Sieka
4131c609719bSwdenk  autoload	- if set to "no" (any string beginning with 'n'),
4132c609719bSwdenk		  "bootp" will just load perform a lookup of the
4133c609719bSwdenk		  configuration from the BOOTP server, but not try to
4134c609719bSwdenk		  load any image using TFTP
4135c609719bSwdenk
4136c609719bSwdenk  autostart	- if set to "yes", an image loaded using the "bootp",
4137c609719bSwdenk		  "rarpboot", "tftpboot" or "diskboot" commands will
4138c609719bSwdenk		  be automatically started (by internally calling
4139c609719bSwdenk		  "bootm")
4140c609719bSwdenk
41414a6fd34bSwdenk		  If set to "no", a standalone image passed to the
41424a6fd34bSwdenk		  "bootm" command will be copied to the load address
41434a6fd34bSwdenk		  (and eventually uncompressed), but NOT be started.
41444a6fd34bSwdenk		  This can be used to load and uncompress arbitrary
41454a6fd34bSwdenk		  data.
41464a6fd34bSwdenk
4147a28afca5SDavid A. Long  fdt_high	- if set this restricts the maximum address that the
4148a28afca5SDavid A. Long		  flattened device tree will be copied into upon boot.
4149fa34f6b2SShawn Guo		  For example, if you have a system with 1 GB memory
4150fa34f6b2SShawn Guo		  at physical address 0x10000000, while Linux kernel
4151fa34f6b2SShawn Guo		  only recognizes the first 704 MB as low memory, you
4152fa34f6b2SShawn Guo		  may need to set fdt_high as 0x3C000000 to have the
4153fa34f6b2SShawn Guo		  device tree blob be copied to the maximum address
4154fa34f6b2SShawn Guo		  of the 704 MB low memory, so that Linux kernel can
4155fa34f6b2SShawn Guo		  access it during the boot procedure.
4156fa34f6b2SShawn Guo
4157a28afca5SDavid A. Long		  If this is set to the special value 0xFFFFFFFF then
4158a28afca5SDavid A. Long		  the fdt will not be copied at all on boot.  For this
4159a28afca5SDavid A. Long		  to work it must reside in writable memory, have
4160a28afca5SDavid A. Long		  sufficient padding on the end of it for u-boot to
4161a28afca5SDavid A. Long		  add the information it needs into it, and the memory
4162a28afca5SDavid A. Long		  must be accessible by the kernel.
4163a28afca5SDavid A. Long
4164eea63e05SSimon Glass  fdtcontroladdr- if set this is the address of the control flattened
4165eea63e05SSimon Glass		  device tree used by U-Boot when CONFIG_OF_CONTROL is
4166eea63e05SSimon Glass		  defined.
4167eea63e05SSimon Glass
416817ea1177Swdenk  i2cfast	- (PPC405GP|PPC405EP only)
416917ea1177Swdenk		  if set to 'y' configures Linux I2C driver for fast
417017ea1177Swdenk		  mode (400kHZ). This environment variable is used in
417117ea1177Swdenk		  initialization code. So, for changes to be effective
417217ea1177Swdenk		  it must be saved and board must be reset.
417317ea1177Swdenk
4174c609719bSwdenk  initrd_high	- restrict positioning of initrd images:
4175c609719bSwdenk		  If this variable is not set, initrd images will be
4176c609719bSwdenk		  copied to the highest possible address in RAM; this
4177c609719bSwdenk		  is usually what you want since it allows for
4178c609719bSwdenk		  maximum initrd size. If for some reason you want to
4179c609719bSwdenk		  make sure that the initrd image is loaded below the
41806d0f6bcfSJean-Christophe PLAGNIOL-VILLARD		  CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4181c609719bSwdenk		  variable to a value of "no" or "off" or "0".
4182c609719bSwdenk		  Alternatively, you can set it to a maximum upper
4183c609719bSwdenk		  address to use (U-Boot will still check that it
4184c609719bSwdenk		  does not overwrite the U-Boot stack and data).
4185c609719bSwdenk
4186c609719bSwdenk		  For instance, when you have a system with 16 MB
41877152b1d0Swdenk		  RAM, and want to reserve 4 MB from use by Linux,
4188c609719bSwdenk		  you can do this by adding "mem=12M" to the value of
4189c609719bSwdenk		  the "bootargs" variable. However, now you must make
41907152b1d0Swdenk		  sure that the initrd image is placed in the first
4191c609719bSwdenk		  12 MB as well - this can be done with
4192c609719bSwdenk
4193c609719bSwdenk		  setenv initrd_high 00c00000
4194c609719bSwdenk
419538b99261Swdenk		  If you set initrd_high to 0xFFFFFFFF, this is an
419638b99261Swdenk		  indication to U-Boot that all addresses are legal
419738b99261Swdenk		  for the Linux kernel, including addresses in flash
419838b99261Swdenk		  memory. In this case U-Boot will NOT COPY the
419938b99261Swdenk		  ramdisk at all. This may be useful to reduce the
420038b99261Swdenk		  boot time on your system, but requires that this
420138b99261Swdenk		  feature is supported by your Linux kernel.
420238b99261Swdenk
4203c609719bSwdenk  ipaddr	- IP address; needed for tftpboot command
4204c609719bSwdenk
4205c609719bSwdenk  loadaddr	- Default load address for commands like "bootp",
4206dc7c9a1aSwdenk		  "rarpboot", "tftpboot", "loadb" or "diskboot"
4207c609719bSwdenk
4208c609719bSwdenk  loads_echo	- see CONFIG_LOADS_ECHO
4209c609719bSwdenk
4210c609719bSwdenk  serverip	- TFTP server IP address; needed for tftpboot command
4211c609719bSwdenk
4212c609719bSwdenk  bootretry	- see CONFIG_BOOT_RETRY_TIME
4213c609719bSwdenk
4214c609719bSwdenk  bootdelaykey	- see CONFIG_AUTOBOOT_DELAY_STR
4215c609719bSwdenk
4216c609719bSwdenk  bootstopkey	- see CONFIG_AUTOBOOT_STOP_STR
4217c609719bSwdenk
4218e2a53458SMike Frysinger  ethprime	- controls which interface is used first.
4219a3d991bdSwdenk
4220e2a53458SMike Frysinger  ethact	- controls which interface is currently active.
4221e2a53458SMike Frysinger		  For example you can do the following
4222a3d991bdSwdenk
422348690d80SHeiko Schocher		  => setenv ethact FEC
422448690d80SHeiko Schocher		  => ping 192.168.0.1 # traffic sent on FEC
422548690d80SHeiko Schocher		  => setenv ethact SCC
422648690d80SHeiko Schocher		  => ping 10.0.0.1 # traffic sent on SCC
4227a3d991bdSwdenk
4228e1692577SMatthias Fuchs  ethrotate	- When set to "no" U-Boot does not go through all
4229e1692577SMatthias Fuchs		  available network interfaces.
4230e1692577SMatthias Fuchs		  It just stays at the currently selected interface.
4231e1692577SMatthias Fuchs
4232a3d991bdSwdenk  netretry	- When set to "no" each network operation will
4233a3d991bdSwdenk		  either succeed or fail without retrying.
42346e592385Swdenk		  When set to "once" the network operation will
42356e592385Swdenk		  fail when all the available network interfaces
42366e592385Swdenk		  are tried once without success.
4237a3d991bdSwdenk		  Useful on scripts which control the retry operation
4238a3d991bdSwdenk		  themselves.
4239a3d991bdSwdenk
4240b4e2f89dSJean-Christophe PLAGNIOL-VILLARD  npe_ucode	- set load address for the NPE microcode
4241a1cf027aSJean-Christophe PLAGNIOL-VILLARD
424228cb9375SWolfgang Denk  tftpsrcport	- If this is set, the value is used for TFTP's
4243ecb0ccd9SWolfgang Denk		  UDP source port.
4244ecb0ccd9SWolfgang Denk
424528cb9375SWolfgang Denk  tftpdstport	- If this is set, the value is used for TFTP's UDP
424628cb9375SWolfgang Denk		  destination port instead of the Well Know Port 69.
424728cb9375SWolfgang Denk
4248c96f86eeSWolfgang Denk  tftpblocksize - Block size to use for TFTP transfers; if not set,
4249c96f86eeSWolfgang Denk		  we use the TFTP server's default block size
4250c96f86eeSWolfgang Denk
4251c96f86eeSWolfgang Denk  tftptimeout	- Retransmission timeout for TFTP packets (in milli-
4252c96f86eeSWolfgang Denk		  seconds, minimum value is 1000 = 1 second). Defines
4253c96f86eeSWolfgang Denk		  when a packet is considered to be lost so it has to
4254c96f86eeSWolfgang Denk		  be retransmitted. The default is 5000 = 5 seconds.
4255c96f86eeSWolfgang Denk		  Lowering this value may make downloads succeed
4256c96f86eeSWolfgang Denk		  faster in networks with high packet loss rates or
4257c96f86eeSWolfgang Denk		  with unreliable TFTP servers.
4258c96f86eeSWolfgang Denk
4259a3d991bdSwdenk  vlan		- When set to a value < 4095 the traffic over
426011ccc33fSMarcel Ziswiler		  Ethernet is encapsulated/received over 802.1q
4261a3d991bdSwdenk		  VLAN tagged frames.
4262c609719bSwdenk
4263dc0b7b0eSJason HobbsThe following image location variables contain the location of images
4264dc0b7b0eSJason Hobbsused in booting. The "Image" column gives the role of the image and is
4265dc0b7b0eSJason Hobbsnot an environment variable name. The other columns are environment
4266dc0b7b0eSJason Hobbsvariable names. "File Name" gives the name of the file on a TFTP
4267dc0b7b0eSJason Hobbsserver, "RAM Address" gives the location in RAM the image will be
4268dc0b7b0eSJason Hobbsloaded to, and "Flash Location" gives the image's address in NOR
4269dc0b7b0eSJason Hobbsflash or offset in NAND flash.
4270dc0b7b0eSJason Hobbs
4271dc0b7b0eSJason Hobbs*Note* - these variables don't have to be defined for all boards, some
4272dc0b7b0eSJason Hobbsboards currenlty use other variables for these purposes, and some
4273dc0b7b0eSJason Hobbsboards use these variables for other purposes.
4274dc0b7b0eSJason Hobbs
4275dc0b7b0eSJason HobbsImage		    File Name	     RAM Address       Flash Location
4276dc0b7b0eSJason Hobbs-----		    ---------	     -----------       --------------
4277dc0b7b0eSJason Hobbsu-boot		    u-boot	     u-boot_addr_r     u-boot_addr
4278dc0b7b0eSJason HobbsLinux kernel	    bootfile	     kernel_addr_r     kernel_addr
4279dc0b7b0eSJason Hobbsdevice tree blob    fdtfile	     fdt_addr_r	       fdt_addr
4280dc0b7b0eSJason Hobbsramdisk		    ramdiskfile	     ramdisk_addr_r    ramdisk_addr
4281dc0b7b0eSJason Hobbs
4282c609719bSwdenkThe following environment variables may be used and automatically
4283c609719bSwdenkupdated by the network boot commands ("bootp" and "rarpboot"),
4284c609719bSwdenkdepending the information provided by your boot server:
4285c609719bSwdenk
4286c609719bSwdenk  bootfile	- see above
4287c609719bSwdenk  dnsip		- IP address of your Domain Name Server
4288fe389a82Sstroese  dnsip2	- IP address of your secondary Domain Name Server
4289c609719bSwdenk  gatewayip	- IP address of the Gateway (Router) to use
4290c609719bSwdenk  hostname	- Target hostname
4291c609719bSwdenk  ipaddr	- see above
4292c609719bSwdenk  netmask	- Subnet Mask
4293c609719bSwdenk  rootpath	- Pathname of the root filesystem on the NFS server
4294c609719bSwdenk  serverip	- see above
4295c609719bSwdenk
4296c609719bSwdenk
4297c609719bSwdenkThere are two special Environment Variables:
4298c609719bSwdenk
4299c609719bSwdenk  serial#	- contains hardware identification information such
4300c609719bSwdenk		  as type string and/or serial number
4301c609719bSwdenk  ethaddr	- Ethernet address
4302c609719bSwdenk
4303c609719bSwdenkThese variables can be set only once (usually during manufacturing of
4304c609719bSwdenkthe board). U-Boot refuses to delete or overwrite these variables
4305c609719bSwdenkonce they have been set once.
4306c609719bSwdenk
4307c609719bSwdenk
4308c1551ea8SstroeseFurther special Environment Variables:
4309c1551ea8Sstroese
4310c1551ea8Sstroese  ver		- Contains the U-Boot version string as printed
4311c1551ea8Sstroese		  with the "version" command. This variable is
4312c1551ea8Sstroese		  readonly (see CONFIG_VERSION_VARIABLE).
4313c1551ea8Sstroese
4314c1551ea8Sstroese
4315c609719bSwdenkPlease note that changes to some configuration parameters may take
4316c609719bSwdenkonly effect after the next boot (yes, that's just like Windoze :-).
4317c609719bSwdenk
4318c609719bSwdenk
4319170ab110SJoe HershbergerCallback functions for environment variables:
4320170ab110SJoe Hershberger---------------------------------------------
4321170ab110SJoe Hershberger
4322170ab110SJoe HershbergerFor some environment variables, the behavior of u-boot needs to change
4323170ab110SJoe Hershbergerwhen their values are changed.  This functionailty allows functions to
4324170ab110SJoe Hershbergerbe associated with arbitrary variables.  On creation, overwrite, or
4325170ab110SJoe Hershbergerdeletion, the callback will provide the opportunity for some side
4326170ab110SJoe Hershbergereffect to happen or for the change to be rejected.
4327170ab110SJoe Hershberger
4328170ab110SJoe HershbergerThe callbacks are named and associated with a function using the
4329170ab110SJoe HershbergerU_BOOT_ENV_CALLBACK macro in your board or driver code.
4330170ab110SJoe Hershberger
4331170ab110SJoe HershbergerThese callbacks are associated with variables in one of two ways.  The
4332170ab110SJoe Hershbergerstatic list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4333170ab110SJoe Hershbergerin the board configuration to a string that defines a list of
4334170ab110SJoe Hershbergerassociations.  The list must be in the following format:
4335170ab110SJoe Hershberger
4336170ab110SJoe Hershberger	entry = variable_name[:callback_name]
4337170ab110SJoe Hershberger	list = entry[,list]
4338170ab110SJoe Hershberger
4339170ab110SJoe HershbergerIf the callback name is not specified, then the callback is deleted.
4340170ab110SJoe HershbergerSpaces are also allowed anywhere in the list.
4341170ab110SJoe Hershberger
4342170ab110SJoe HershbergerCallbacks can also be associated by defining the ".callbacks" variable
4343170ab110SJoe Hershbergerwith the same list format above.  Any association in ".callbacks" will
4344170ab110SJoe Hershbergeroverride any association in the static list. You can define
4345170ab110SJoe HershbergerCONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4346170ab110SJoe Hershberger".callbacks" envirnoment variable in the default or embedded environment.
4347170ab110SJoe Hershberger
4348170ab110SJoe Hershberger
4349f07771ccSwdenkCommand Line Parsing:
4350f07771ccSwdenk=====================
4351f07771ccSwdenk
4352f07771ccSwdenkThere are two different command line parsers available with U-Boot:
43537152b1d0Swdenkthe old "simple" one, and the much more powerful "hush" shell:
4354f07771ccSwdenk
4355f07771ccSwdenkOld, simple command line parser:
4356f07771ccSwdenk--------------------------------
4357f07771ccSwdenk
4358f07771ccSwdenk- supports environment variables (through setenv / saveenv commands)
4359f07771ccSwdenk- several commands on one line, separated by ';'
4360fe126d8bSWolfgang Denk- variable substitution using "... ${name} ..." syntax
4361f07771ccSwdenk- special characters ('$', ';') can be escaped by prefixing with '\',
4362f07771ccSwdenk  for example:
4363fe126d8bSWolfgang Denk	setenv bootcmd bootm \${address}
4364f07771ccSwdenk- You can also escape text by enclosing in single apostrophes, for example:
4365f07771ccSwdenk	setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4366f07771ccSwdenk
4367f07771ccSwdenkHush shell:
4368f07771ccSwdenk-----------
4369f07771ccSwdenk
4370f07771ccSwdenk- similar to Bourne shell, with control structures like
4371f07771ccSwdenk  if...then...else...fi, for...do...done; while...do...done,
4372f07771ccSwdenk  until...do...done, ...
4373f07771ccSwdenk- supports environment ("global") variables (through setenv / saveenv
4374f07771ccSwdenk  commands) and local shell variables (through standard shell syntax
4375f07771ccSwdenk  "name=value"); only environment variables can be used with "run"
4376f07771ccSwdenk  command
4377f07771ccSwdenk
4378f07771ccSwdenkGeneral rules:
4379f07771ccSwdenk--------------
4380f07771ccSwdenk
4381f07771ccSwdenk(1) If a command line (or an environment variable executed by a "run"
4382f07771ccSwdenk    command) contains several commands separated by semicolon, and
4383f07771ccSwdenk    one of these commands fails, then the remaining commands will be
4384f07771ccSwdenk    executed anyway.
4385f07771ccSwdenk
4386f07771ccSwdenk(2) If you execute several variables with one call to run (i. e.
438711ccc33fSMarcel Ziswiler    calling run with a list of variables as arguments), any failing
4388f07771ccSwdenk    command will cause "run" to terminate, i. e. the remaining
4389f07771ccSwdenk    variables are not executed.
4390f07771ccSwdenk
4391c609719bSwdenkNote for Redundant Ethernet Interfaces:
4392c609719bSwdenk=======================================
4393c609719bSwdenk
439411ccc33fSMarcel ZiswilerSome boards come with redundant Ethernet interfaces; U-Boot supports
4395c609719bSwdenksuch configurations and is capable of automatic selection of a
43967152b1d0Swdenk"working" interface when needed. MAC assignment works as follows:
4397c609719bSwdenk
4398c609719bSwdenkNetwork interfaces are numbered eth0, eth1, eth2, ... Corresponding
4399c609719bSwdenkMAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4400c609719bSwdenk"eth1addr" (=>eth1), "eth2addr", ...
4401c609719bSwdenk
4402c609719bSwdenkIf the network interface stores some valid MAC address (for instance
4403c609719bSwdenkin SROM), this is used as default address if there is NO correspon-
4404c609719bSwdenkding setting in the environment; if the corresponding environment
4405c609719bSwdenkvariable is set, this overrides the settings in the card; that means:
4406c609719bSwdenk
4407c609719bSwdenko If the SROM has a valid MAC address, and there is no address in the
4408c609719bSwdenk  environment, the SROM's address is used.
4409c609719bSwdenk
4410c609719bSwdenko If there is no valid address in the SROM, and a definition in the
4411c609719bSwdenk  environment exists, then the value from the environment variable is
4412c609719bSwdenk  used.
4413c609719bSwdenk
4414c609719bSwdenko If both the SROM and the environment contain a MAC address, and
4415c609719bSwdenk  both addresses are the same, this MAC address is used.
4416c609719bSwdenk
4417c609719bSwdenko If both the SROM and the environment contain a MAC address, and the
4418c609719bSwdenk  addresses differ, the value from the environment is used and a
4419c609719bSwdenk  warning is printed.
4420c609719bSwdenk
4421c609719bSwdenko If neither SROM nor the environment contain a MAC address, an error
4422c609719bSwdenk  is raised.
4423c609719bSwdenk
4424ecee9324SBen WarrenIf Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4425ecee9324SBen Warrenwill be programmed into hardware as part of the initialization process.	 This
4426ecee9324SBen Warrenmay be skipped by setting the appropriate 'ethmacskip' environment variable.
4427ecee9324SBen WarrenThe naming convention is as follows:
4428ecee9324SBen Warren"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4429c609719bSwdenk
4430c609719bSwdenkImage Formats:
4431c609719bSwdenk==============
4432c609719bSwdenk
44333310c549SMarian BalakowiczU-Boot is capable of booting (and performing other auxiliary operations on)
44343310c549SMarian Balakowiczimages in two formats:
44353310c549SMarian Balakowicz
44363310c549SMarian BalakowiczNew uImage format (FIT)
44373310c549SMarian Balakowicz-----------------------
44383310c549SMarian Balakowicz
44393310c549SMarian BalakowiczFlexible and powerful format based on Flattened Image Tree -- FIT (similar
44403310c549SMarian Balakowiczto Flattened Device Tree). It allows the use of images with multiple
44413310c549SMarian Balakowiczcomponents (several kernels, ramdisks, etc.), with contents protected by
44423310c549SMarian BalakowiczSHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
44433310c549SMarian Balakowicz
44443310c549SMarian Balakowicz
44453310c549SMarian BalakowiczOld uImage format
44463310c549SMarian Balakowicz-----------------
44473310c549SMarian Balakowicz
44483310c549SMarian BalakowiczOld image format is based on binary files which can be basically anything,
44493310c549SMarian Balakowiczpreceded by a special header; see the definitions in include/image.h for
44503310c549SMarian Balakowiczdetails; basically, the header defines the following image properties:
4451c609719bSwdenk
4452c609719bSwdenk* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4453c609719bSwdenk  4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4454f5ed9e39SPeter Tyser  LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4455f5ed9e39SPeter Tyser  Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4456f5ed9e39SPeter Tyser  INTEGRITY).
44577b64fef3SWolfgang Denk* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4458afc1ce82SMacpaul Lin  IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4459afc1ce82SMacpaul Lin  Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4460c29fdfc1Swdenk* Compression Type (uncompressed, gzip, bzip2)
4461c609719bSwdenk* Load Address
4462c609719bSwdenk* Entry Point
4463c609719bSwdenk* Image Name
4464c609719bSwdenk* Image Timestamp
4465c609719bSwdenk
4466c609719bSwdenkThe header is marked by a special Magic Number, and both the header
4467c609719bSwdenkand the data portions of the image are secured against corruption by
4468c609719bSwdenkCRC32 checksums.
4469c609719bSwdenk
4470c609719bSwdenk
4471c609719bSwdenkLinux Support:
4472c609719bSwdenk==============
4473c609719bSwdenk
4474c609719bSwdenkAlthough U-Boot should support any OS or standalone application
44757152b1d0Swdenkeasily, the main focus has always been on Linux during the design of
4476c609719bSwdenkU-Boot.
4477c609719bSwdenk
4478c609719bSwdenkU-Boot includes many features that so far have been part of some
4479c609719bSwdenkspecial "boot loader" code within the Linux kernel. Also, any
4480c609719bSwdenk"initrd" images to be used are no longer part of one big Linux image;
4481c609719bSwdenkinstead, kernel and "initrd" are separate images. This implementation
44827152b1d0Swdenkserves several purposes:
4483c609719bSwdenk
4484c609719bSwdenk- the same features can be used for other OS or standalone
4485c609719bSwdenk  applications (for instance: using compressed images to reduce the
4486c609719bSwdenk  Flash memory footprint)
4487c609719bSwdenk
4488c609719bSwdenk- it becomes much easier to port new Linux kernel versions because
44897152b1d0Swdenk  lots of low-level, hardware dependent stuff are done by U-Boot
4490c609719bSwdenk
4491c609719bSwdenk- the same Linux kernel image can now be used with different "initrd"
4492c609719bSwdenk  images; of course this also means that different kernel images can
4493c609719bSwdenk  be run with the same "initrd". This makes testing easier (you don't
4494c609719bSwdenk  have to build a new "zImage.initrd" Linux image when you just
4495c609719bSwdenk  change a file in your "initrd"). Also, a field-upgrade of the
4496c609719bSwdenk  software is easier now.
4497c609719bSwdenk
4498c609719bSwdenk
4499c609719bSwdenkLinux HOWTO:
4500c609719bSwdenk============
4501c609719bSwdenk
4502c609719bSwdenkPorting Linux to U-Boot based systems:
4503c609719bSwdenk---------------------------------------
4504c609719bSwdenk
4505c609719bSwdenkU-Boot cannot save you from doing all the necessary modifications to
4506c609719bSwdenkconfigure the Linux device drivers for use with your target hardware
4507c609719bSwdenk(no, we don't intend to provide a full virtual machine interface to
4508c609719bSwdenkLinux :-).
4509c609719bSwdenk
4510a47a12beSStefan RoeseBut now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4511c609719bSwdenk
4512c609719bSwdenkJust make sure your machine specific header file (for instance
4513c609719bSwdenkinclude/asm-ppc/tqm8xx.h) includes the same definition of the Board
45141dc30693SMarkus HeidelbergInformation structure as we define in include/asm-<arch>/u-boot.h,
45151dc30693SMarkus Heidelbergand make sure that your definition of IMAP_ADDR uses the same value
45166d0f6bcfSJean-Christophe PLAGNIOL-VILLARDas your U-Boot configuration in CONFIG_SYS_IMMR.
4517c609719bSwdenk
4518c609719bSwdenk
4519c609719bSwdenkConfiguring the Linux kernel:
4520c609719bSwdenk-----------------------------
4521c609719bSwdenk
4522c609719bSwdenkNo specific requirements for U-Boot. Make sure you have some root
4523c609719bSwdenkdevice (initial ramdisk, NFS) for your target system.
4524c609719bSwdenk
4525c609719bSwdenk
4526c609719bSwdenkBuilding a Linux Image:
4527c609719bSwdenk-----------------------
4528c609719bSwdenk
452924ee89b9SwdenkWith U-Boot, "normal" build targets like "zImage" or "bzImage" are
453024ee89b9Swdenknot used. If you use recent kernel source, a new build target
453124ee89b9Swdenk"uImage" will exist which automatically builds an image usable by
453224ee89b9SwdenkU-Boot. Most older kernels also have support for a "pImage" target,
453324ee89b9Swdenkwhich was introduced for our predecessor project PPCBoot and uses a
453424ee89b9Swdenk100% compatible format.
4535c609719bSwdenk
4536c609719bSwdenkExample:
4537c609719bSwdenk
4538c609719bSwdenk	make TQM850L_config
4539c609719bSwdenk	make oldconfig
4540c609719bSwdenk	make dep
454124ee89b9Swdenk	make uImage
4542c609719bSwdenk
454324ee89b9SwdenkThe "uImage" build target uses a special tool (in 'tools/mkimage') to
454424ee89b9Swdenkencapsulate a compressed Linux kernel image with header	 information,
454524ee89b9SwdenkCRC32 checksum etc. for use with U-Boot. This is what we are doing:
4546c609719bSwdenk
454724ee89b9Swdenk* build a standard "vmlinux" kernel image (in ELF binary format):
454824ee89b9Swdenk
454924ee89b9Swdenk* convert the kernel into a raw binary image:
455024ee89b9Swdenk
455124ee89b9Swdenk	${CROSS_COMPILE}-objcopy -O binary \
455224ee89b9Swdenk				 -R .note -R .comment \
455324ee89b9Swdenk				 -S vmlinux linux.bin
455424ee89b9Swdenk
455524ee89b9Swdenk* compress the binary image:
455624ee89b9Swdenk
455724ee89b9Swdenk	gzip -9 linux.bin
455824ee89b9Swdenk
455924ee89b9Swdenk* package compressed binary image for U-Boot:
456024ee89b9Swdenk
456124ee89b9Swdenk	mkimage -A ppc -O linux -T kernel -C gzip \
456224ee89b9Swdenk		-a 0 -e 0 -n "Linux Kernel Image" \
456324ee89b9Swdenk		-d linux.bin.gz uImage
456424ee89b9Swdenk
456524ee89b9Swdenk
456624ee89b9SwdenkThe "mkimage" tool can also be used to create ramdisk images for use
456724ee89b9Swdenkwith U-Boot, either separated from the Linux kernel image, or
456824ee89b9Swdenkcombined into one file. "mkimage" encapsulates the images with a 64
456924ee89b9Swdenkbyte header containing information about target architecture,
457024ee89b9Swdenkoperating system, image type, compression method, entry points, time
457124ee89b9Swdenkstamp, CRC32 checksums, etc.
457224ee89b9Swdenk
457324ee89b9Swdenk"mkimage" can be called in two ways: to verify existing images and
457424ee89b9Swdenkprint the header information, or to build new images.
4575c609719bSwdenk
4576c609719bSwdenkIn the first form (with "-l" option) mkimage lists the information
4577c609719bSwdenkcontained in the header of an existing U-Boot image; this includes
4578c609719bSwdenkchecksum verification:
4579c609719bSwdenk
4580c609719bSwdenk	tools/mkimage -l image
4581c609719bSwdenk	  -l ==> list image header information
4582c609719bSwdenk
4583c609719bSwdenkThe second form (with "-d" option) is used to build a U-Boot image
4584c609719bSwdenkfrom a "data file" which is used as image payload:
4585c609719bSwdenk
4586c609719bSwdenk	tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4587c609719bSwdenk		      -n name -d data_file image
4588c609719bSwdenk	  -A ==> set architecture to 'arch'
4589c609719bSwdenk	  -O ==> set operating system to 'os'
4590c609719bSwdenk	  -T ==> set image type to 'type'
4591c609719bSwdenk	  -C ==> set compression type 'comp'
4592c609719bSwdenk	  -a ==> set load address to 'addr' (hex)
4593c609719bSwdenk	  -e ==> set entry point to 'ep' (hex)
4594c609719bSwdenk	  -n ==> set image name to 'name'
4595c609719bSwdenk	  -d ==> use image data from 'datafile'
4596c609719bSwdenk
459769459791SwdenkRight now, all Linux kernels for PowerPC systems use the same load
459869459791Swdenkaddress (0x00000000), but the entry point address depends on the
459969459791Swdenkkernel version:
4600c609719bSwdenk
4601c609719bSwdenk- 2.2.x kernels have the entry point at 0x0000000C,
460224ee89b9Swdenk- 2.3.x and later kernels have the entry point at 0x00000000.
4603c609719bSwdenk
4604c609719bSwdenkSo a typical call to build a U-Boot image would read:
4605c609719bSwdenk
460624ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
460724ee89b9Swdenk	> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4608a47a12beSStefan Roese	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
460924ee89b9Swdenk	> examples/uImage.TQM850L
461024ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4611c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4612c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
4613c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
4614c609719bSwdenk	Load Address: 0x00000000
461524ee89b9Swdenk	Entry Point:  0x00000000
4616c609719bSwdenk
4617c609719bSwdenkTo verify the contents of the image (or check for corruption):
4618c609719bSwdenk
461924ee89b9Swdenk	-> tools/mkimage -l examples/uImage.TQM850L
462024ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4621c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4622c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
4623c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
4624c609719bSwdenk	Load Address: 0x00000000
462524ee89b9Swdenk	Entry Point:  0x00000000
4626c609719bSwdenk
4627c609719bSwdenkNOTE: for embedded systems where boot time is critical you can trade
4628c609719bSwdenkspeed for memory and install an UNCOMPRESSED image instead: this
4629c609719bSwdenkneeds more space in Flash, but boots much faster since it does not
4630c609719bSwdenkneed to be uncompressed:
4631c609719bSwdenk
4632a47a12beSStefan Roese	-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
463324ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
463424ee89b9Swdenk	> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4635a47a12beSStefan Roese	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
463624ee89b9Swdenk	> examples/uImage.TQM850L-uncompressed
463724ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
4638c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
4639c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (uncompressed)
4640c609719bSwdenk	Data Size:    792160 Bytes = 773.59 kB = 0.76 MB
4641c609719bSwdenk	Load Address: 0x00000000
464224ee89b9Swdenk	Entry Point:  0x00000000
4643c609719bSwdenk
4644c609719bSwdenk
4645c609719bSwdenkSimilar you can build U-Boot images from a 'ramdisk.image.gz' file
4646c609719bSwdenkwhen your kernel is intended to use an initial ramdisk:
4647c609719bSwdenk
4648c609719bSwdenk	-> tools/mkimage -n 'Simple Ramdisk Image' \
4649c609719bSwdenk	> -A ppc -O linux -T ramdisk -C gzip \
4650c609719bSwdenk	> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4651c609719bSwdenk	Image Name:   Simple Ramdisk Image
4652c609719bSwdenk	Created:      Wed Jan 12 14:01:50 2000
4653c609719bSwdenk	Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
4654c609719bSwdenk	Data Size:    566530 Bytes = 553.25 kB = 0.54 MB
4655c609719bSwdenk	Load Address: 0x00000000
4656c609719bSwdenk	Entry Point:  0x00000000
4657c609719bSwdenk
4658c609719bSwdenk
4659c609719bSwdenkInstalling a Linux Image:
4660c609719bSwdenk-------------------------
4661c609719bSwdenk
4662c609719bSwdenkTo downloading a U-Boot image over the serial (console) interface,
4663c609719bSwdenkyou must convert the image to S-Record format:
4664c609719bSwdenk
4665c609719bSwdenk	objcopy -I binary -O srec examples/image examples/image.srec
4666c609719bSwdenk
4667c609719bSwdenkThe 'objcopy' does not understand the information in the U-Boot
4668c609719bSwdenkimage header, so the resulting S-Record file will be relative to
4669c609719bSwdenkaddress 0x00000000. To load it to a given address, you need to
4670c609719bSwdenkspecify the target address as 'offset' parameter with the 'loads'
4671c609719bSwdenkcommand.
4672c609719bSwdenk
4673c609719bSwdenkExample: install the image to address 0x40100000 (which on the
4674c609719bSwdenkTQM8xxL is in the first Flash bank):
4675c609719bSwdenk
4676c609719bSwdenk	=> erase 40100000 401FFFFF
4677c609719bSwdenk
4678c609719bSwdenk	.......... done
4679c609719bSwdenk	Erased 8 sectors
4680c609719bSwdenk
4681c609719bSwdenk	=> loads 40100000
4682c609719bSwdenk	## Ready for S-Record download ...
4683c609719bSwdenk	~>examples/image.srec
4684c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4685c609719bSwdenk	...
4686c609719bSwdenk	15989 15990 15991 15992
4687c609719bSwdenk	[file transfer complete]
4688c609719bSwdenk	[connected]
4689c609719bSwdenk	## Start Addr = 0x00000000
4690c609719bSwdenk
4691c609719bSwdenk
4692c609719bSwdenkYou can check the success of the download using the 'iminfo' command;
4693c609719bSwdenkthis includes a checksum verification so you can be sure no data
4694c609719bSwdenkcorruption happened:
4695c609719bSwdenk
4696c609719bSwdenk	=> imi 40100000
4697c609719bSwdenk
4698c609719bSwdenk	## Checking Image at 40100000 ...
4699c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4700c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4701c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4702c609719bSwdenk	   Load Address: 00000000
4703c609719bSwdenk	   Entry Point:	 0000000c
4704c609719bSwdenk	   Verifying Checksum ... OK
4705c609719bSwdenk
4706c609719bSwdenk
4707c609719bSwdenkBoot Linux:
4708c609719bSwdenk-----------
4709c609719bSwdenk
4710c609719bSwdenkThe "bootm" command is used to boot an application that is stored in
4711c609719bSwdenkmemory (RAM or Flash). In case of a Linux kernel image, the contents
4712c609719bSwdenkof the "bootargs" environment variable is passed to the kernel as
4713c609719bSwdenkparameters. You can check and modify this variable using the
4714c609719bSwdenk"printenv" and "setenv" commands:
4715c609719bSwdenk
4716c609719bSwdenk
4717c609719bSwdenk	=> printenv bootargs
4718c609719bSwdenk	bootargs=root=/dev/ram
4719c609719bSwdenk
4720c609719bSwdenk	=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4721c609719bSwdenk
4722c609719bSwdenk	=> printenv bootargs
4723c609719bSwdenk	bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4724c609719bSwdenk
4725c609719bSwdenk	=> bootm 40020000
4726c609719bSwdenk	## Booting Linux kernel at 40020000 ...
4727c609719bSwdenk	   Image Name:	 2.2.13 for NFS on TQM850L
4728c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4729c609719bSwdenk	   Data Size:	 381681 Bytes = 372 kB = 0 MB
4730c609719bSwdenk	   Load Address: 00000000
4731c609719bSwdenk	   Entry Point:	 0000000c
4732c609719bSwdenk	   Verifying Checksum ... OK
4733c609719bSwdenk	   Uncompressing Kernel Image ... OK
4734c609719bSwdenk	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
4735c609719bSwdenk	Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4736c609719bSwdenk	time_init: decrementer frequency = 187500000/60
4737c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
4738c609719bSwdenk	Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4739c609719bSwdenk	...
4740c609719bSwdenk
474111ccc33fSMarcel ZiswilerIf you want to boot a Linux kernel with initial RAM disk, you pass
47427152b1d0Swdenkthe memory addresses of both the kernel and the initrd image (PPBCOOT
4743c609719bSwdenkformat!) to the "bootm" command:
4744c609719bSwdenk
4745c609719bSwdenk	=> imi 40100000 40200000
4746c609719bSwdenk
4747c609719bSwdenk	## Checking Image at 40100000 ...
4748c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4749c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4750c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4751c609719bSwdenk	   Load Address: 00000000
4752c609719bSwdenk	   Entry Point:	 0000000c
4753c609719bSwdenk	   Verifying Checksum ... OK
4754c609719bSwdenk
4755c609719bSwdenk	## Checking Image at 40200000 ...
4756c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
4757c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
4758c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
4759c609719bSwdenk	   Load Address: 00000000
4760c609719bSwdenk	   Entry Point:	 00000000
4761c609719bSwdenk	   Verifying Checksum ... OK
4762c609719bSwdenk
4763c609719bSwdenk	=> bootm 40100000 40200000
4764c609719bSwdenk	## Booting Linux kernel at 40100000 ...
4765c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
4766c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
4767c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
4768c609719bSwdenk	   Load Address: 00000000
4769c609719bSwdenk	   Entry Point:	 0000000c
4770c609719bSwdenk	   Verifying Checksum ... OK
4771c609719bSwdenk	   Uncompressing Kernel Image ... OK
4772c609719bSwdenk	## Loading RAMDisk Image at 40200000 ...
4773c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
4774c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
4775c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
4776c609719bSwdenk	   Load Address: 00000000
4777c609719bSwdenk	   Entry Point:	 00000000
4778c609719bSwdenk	   Verifying Checksum ... OK
4779c609719bSwdenk	   Loading Ramdisk ... OK
4780c609719bSwdenk	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
4781c609719bSwdenk	Boot arguments: root=/dev/ram
4782c609719bSwdenk	time_init: decrementer frequency = 187500000/60
4783c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
4784c609719bSwdenk	...
4785c609719bSwdenk	RAMDISK: Compressed image found at block 0
4786c609719bSwdenk	VFS: Mounted root (ext2 filesystem).
4787c609719bSwdenk
4788c609719bSwdenk	bash#
4789c609719bSwdenk
47900267768eSMatthew McClintockBoot Linux and pass a flat device tree:
47910267768eSMatthew McClintock-----------
47920267768eSMatthew McClintock
47930267768eSMatthew McClintockFirst, U-Boot must be compiled with the appropriate defines. See the section
47940267768eSMatthew McClintocktitled "Linux Kernel Interface" above for a more in depth explanation. The
47950267768eSMatthew McClintockfollowing is an example of how to start a kernel and pass an updated
47960267768eSMatthew McClintockflat device tree:
47970267768eSMatthew McClintock
47980267768eSMatthew McClintock=> print oftaddr
47990267768eSMatthew McClintockoftaddr=0x300000
48000267768eSMatthew McClintock=> print oft
48010267768eSMatthew McClintockoft=oftrees/mpc8540ads.dtb
48020267768eSMatthew McClintock=> tftp $oftaddr $oft
48030267768eSMatthew McClintockSpeed: 1000, full duplex
48040267768eSMatthew McClintockUsing TSEC0 device
48050267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.101
48060267768eSMatthew McClintockFilename 'oftrees/mpc8540ads.dtb'.
48070267768eSMatthew McClintockLoad address: 0x300000
48080267768eSMatthew McClintockLoading: #
48090267768eSMatthew McClintockdone
48100267768eSMatthew McClintockBytes transferred = 4106 (100a hex)
48110267768eSMatthew McClintock=> tftp $loadaddr $bootfile
48120267768eSMatthew McClintockSpeed: 1000, full duplex
48130267768eSMatthew McClintockUsing TSEC0 device
48140267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.2
48150267768eSMatthew McClintockFilename 'uImage'.
48160267768eSMatthew McClintockLoad address: 0x200000
48170267768eSMatthew McClintockLoading:############
48180267768eSMatthew McClintockdone
48190267768eSMatthew McClintockBytes transferred = 1029407 (fb51f hex)
48200267768eSMatthew McClintock=> print loadaddr
48210267768eSMatthew McClintockloadaddr=200000
48220267768eSMatthew McClintock=> print oftaddr
48230267768eSMatthew McClintockoftaddr=0x300000
48240267768eSMatthew McClintock=> bootm $loadaddr - $oftaddr
48250267768eSMatthew McClintock## Booting image at 00200000 ...
48260267768eSMatthew McClintock   Image Name:	 Linux-2.6.17-dirty
48270267768eSMatthew McClintock   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
48280267768eSMatthew McClintock   Data Size:	 1029343 Bytes = 1005.2 kB
48290267768eSMatthew McClintock   Load Address: 00000000
48300267768eSMatthew McClintock   Entry Point:	 00000000
48310267768eSMatthew McClintock   Verifying Checksum ... OK
48320267768eSMatthew McClintock   Uncompressing Kernel Image ... OK
48330267768eSMatthew McClintockBooting using flat device tree at 0x300000
48340267768eSMatthew McClintockUsing MPC85xx ADS machine description
48350267768eSMatthew McClintockMemory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
48360267768eSMatthew McClintock[snip]
48370267768eSMatthew McClintock
48380267768eSMatthew McClintock
48396069ff26SwdenkMore About U-Boot Image Types:
48406069ff26Swdenk------------------------------
48416069ff26Swdenk
48426069ff26SwdenkU-Boot supports the following image types:
48436069ff26Swdenk
48446069ff26Swdenk   "Standalone Programs" are directly runnable in the environment
48456069ff26Swdenk	provided by U-Boot; it is expected that (if they behave
48466069ff26Swdenk	well) you can continue to work in U-Boot after return from
48476069ff26Swdenk	the Standalone Program.
48486069ff26Swdenk   "OS Kernel Images" are usually images of some Embedded OS which
48496069ff26Swdenk	will take over control completely. Usually these programs
48506069ff26Swdenk	will install their own set of exception handlers, device
48516069ff26Swdenk	drivers, set up the MMU, etc. - this means, that you cannot
48526069ff26Swdenk	expect to re-enter U-Boot except by resetting the CPU.
48536069ff26Swdenk   "RAMDisk Images" are more or less just data blocks, and their
48546069ff26Swdenk	parameters (address, size) are passed to an OS kernel that is
48556069ff26Swdenk	being started.
48566069ff26Swdenk   "Multi-File Images" contain several images, typically an OS
48576069ff26Swdenk	(Linux) kernel image and one or more data images like
48586069ff26Swdenk	RAMDisks. This construct is useful for instance when you want
48596069ff26Swdenk	to boot over the network using BOOTP etc., where the boot
48606069ff26Swdenk	server provides just a single image file, but you want to get
48616069ff26Swdenk	for instance an OS kernel and a RAMDisk image.
48626069ff26Swdenk
48636069ff26Swdenk	"Multi-File Images" start with a list of image sizes, each
48646069ff26Swdenk	image size (in bytes) specified by an "uint32_t" in network
48656069ff26Swdenk	byte order. This list is terminated by an "(uint32_t)0".
48666069ff26Swdenk	Immediately after the terminating 0 follow the images, one by
48676069ff26Swdenk	one, all aligned on "uint32_t" boundaries (size rounded up to
48686069ff26Swdenk	a multiple of 4 bytes).
48696069ff26Swdenk
48706069ff26Swdenk   "Firmware Images" are binary images containing firmware (like
48716069ff26Swdenk	U-Boot or FPGA images) which usually will be programmed to
48726069ff26Swdenk	flash memory.
48736069ff26Swdenk
48746069ff26Swdenk   "Script files" are command sequences that will be executed by
48756069ff26Swdenk	U-Boot's command interpreter; this feature is especially
48766069ff26Swdenk	useful when you configure U-Boot to use a real shell (hush)
48776069ff26Swdenk	as command interpreter.
48786069ff26Swdenk
487944f074c7SMarek VasutBooting the Linux zImage:
488044f074c7SMarek Vasut-------------------------
488144f074c7SMarek Vasut
488244f074c7SMarek VasutOn some platforms, it's possible to boot Linux zImage. This is done
488344f074c7SMarek Vasutusing the "bootz" command. The syntax of "bootz" command is the same
488444f074c7SMarek Vasutas the syntax of "bootm" command.
488544f074c7SMarek Vasut
4886017e1f3fSMarek VasutNote, defining the CONFIG_SUPPORT_INITRD_RAW allows user to supply
4887017e1f3fSMarek Vasutkernel with raw initrd images. The syntax is slightly different, the
4888017e1f3fSMarek Vasutaddress of the initrd must be augmented by it's size, in the following
4889017e1f3fSMarek Vasutformat: "<initrd addres>:<initrd size>".
4890017e1f3fSMarek Vasut
4891c609719bSwdenk
4892c609719bSwdenkStandalone HOWTO:
4893c609719bSwdenk=================
4894c609719bSwdenk
4895c609719bSwdenkOne of the features of U-Boot is that you can dynamically load and
4896c609719bSwdenkrun "standalone" applications, which can use some resources of
4897c609719bSwdenkU-Boot like console I/O functions or interrupt services.
4898c609719bSwdenk
4899c609719bSwdenkTwo simple examples are included with the sources:
4900c609719bSwdenk
4901c609719bSwdenk"Hello World" Demo:
4902c609719bSwdenk-------------------
4903c609719bSwdenk
4904c609719bSwdenk'examples/hello_world.c' contains a small "Hello World" Demo
4905c609719bSwdenkapplication; it is automatically compiled when you build U-Boot.
4906c609719bSwdenkIt's configured to run at address 0x00040004, so you can play with it
4907c609719bSwdenklike that:
4908c609719bSwdenk
4909c609719bSwdenk	=> loads
4910c609719bSwdenk	## Ready for S-Record download ...
4911c609719bSwdenk	~>examples/hello_world.srec
4912c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
4913c609719bSwdenk	[file transfer complete]
4914c609719bSwdenk	[connected]
4915c609719bSwdenk	## Start Addr = 0x00040004
4916c609719bSwdenk
4917c609719bSwdenk	=> go 40004 Hello World! This is a test.
4918c609719bSwdenk	## Starting application at 0x00040004 ...
4919c609719bSwdenk	Hello World
4920c609719bSwdenk	argc = 7
4921c609719bSwdenk	argv[0] = "40004"
4922c609719bSwdenk	argv[1] = "Hello"
4923c609719bSwdenk	argv[2] = "World!"
4924c609719bSwdenk	argv[3] = "This"
4925c609719bSwdenk	argv[4] = "is"
4926c609719bSwdenk	argv[5] = "a"
4927c609719bSwdenk	argv[6] = "test."
4928c609719bSwdenk	argv[7] = "<NULL>"
4929c609719bSwdenk	Hit any key to exit ...
4930c609719bSwdenk
4931c609719bSwdenk	## Application terminated, rc = 0x0
4932c609719bSwdenk
4933c609719bSwdenkAnother example, which demonstrates how to register a CPM interrupt
4934c609719bSwdenkhandler with the U-Boot code, can be found in 'examples/timer.c'.
4935c609719bSwdenkHere, a CPM timer is set up to generate an interrupt every second.
4936c609719bSwdenkThe interrupt service routine is trivial, just printing a '.'
4937c609719bSwdenkcharacter, but this is just a demo program. The application can be
4938c609719bSwdenkcontrolled by the following keys:
4939c609719bSwdenk
4940c609719bSwdenk	? - print current values og the CPM Timer registers
4941c609719bSwdenk	b - enable interrupts and start timer
4942c609719bSwdenk	e - stop timer and disable interrupts
4943c609719bSwdenk	q - quit application
4944c609719bSwdenk
4945c609719bSwdenk	=> loads
4946c609719bSwdenk	## Ready for S-Record download ...
4947c609719bSwdenk	~>examples/timer.srec
4948c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
4949c609719bSwdenk	[file transfer complete]
4950c609719bSwdenk	[connected]
4951c609719bSwdenk	## Start Addr = 0x00040004
4952c609719bSwdenk
4953c609719bSwdenk	=> go 40004
4954c609719bSwdenk	## Starting application at 0x00040004 ...
4955c609719bSwdenk	TIMERS=0xfff00980
4956c609719bSwdenk	Using timer 1
4957c609719bSwdenk	  tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4958c609719bSwdenk
4959c609719bSwdenkHit 'b':
4960c609719bSwdenk	[q, b, e, ?] Set interval 1000000 us
4961c609719bSwdenk	Enabling timer
4962c609719bSwdenkHit '?':
4963c609719bSwdenk	[q, b, e, ?] ........
4964c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4965c609719bSwdenkHit '?':
4966c609719bSwdenk	[q, b, e, ?] .
4967c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4968c609719bSwdenkHit '?':
4969c609719bSwdenk	[q, b, e, ?] .
4970c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4971c609719bSwdenkHit '?':
4972c609719bSwdenk	[q, b, e, ?] .
4973c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4974c609719bSwdenkHit 'e':
4975c609719bSwdenk	[q, b, e, ?] ...Stopping timer
4976c609719bSwdenkHit 'q':
4977c609719bSwdenk	[q, b, e, ?] ## Application terminated, rc = 0x0
4978c609719bSwdenk
4979c609719bSwdenk
498085ec0bccSwdenkMinicom warning:
498185ec0bccSwdenk================
498285ec0bccSwdenk
49837152b1d0SwdenkOver time, many people have reported problems when trying to use the
498485ec0bccSwdenk"minicom" terminal emulation program for serial download. I (wd)
498585ec0bccSwdenkconsider minicom to be broken, and recommend not to use it. Under
4986f07771ccSwdenkUnix, I recommend to use C-Kermit for general purpose use (and
498785ec0bccSwdenkespecially for kermit binary protocol download ("loadb" command), and
4988e53515a2SKarl O. Pincuse "cu" for S-Record download ("loads" command).  See
4989e53515a2SKarl O. Pinchttp://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4990e53515a2SKarl O. Pincfor help with kermit.
4991e53515a2SKarl O. Pinc
499285ec0bccSwdenk
499352f52c14SwdenkNevertheless, if you absolutely want to use it try adding this
499452f52c14Swdenkconfiguration to your "File transfer protocols" section:
499552f52c14Swdenk
499652f52c14Swdenk	   Name	   Program			Name U/D FullScr IO-Red. Multi
499752f52c14Swdenk	X  kermit  /usr/bin/kermit -i -l %l -s	 Y    U	   Y	   N	  N
499852f52c14Swdenk	Y  kermit  /usr/bin/kermit -i -l %l -r	 N    D	   Y	   N	  N
499952f52c14Swdenk
500052f52c14Swdenk
5001c609719bSwdenkNetBSD Notes:
5002c609719bSwdenk=============
5003c609719bSwdenk
5004c609719bSwdenkStarting at version 0.9.2, U-Boot supports NetBSD both as host
5005c609719bSwdenk(build U-Boot) and target system (boots NetBSD/mpc8xx).
5006c609719bSwdenk
5007c609719bSwdenkBuilding requires a cross environment; it is known to work on
5008c609719bSwdenkNetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5009c609719bSwdenkneed gmake since the Makefiles are not compatible with BSD make).
5010c609719bSwdenkNote that the cross-powerpc package does not install include files;
5011c609719bSwdenkattempting to build U-Boot will fail because <machine/ansi.h> is
5012c609719bSwdenkmissing.  This file has to be installed and patched manually:
5013c609719bSwdenk
5014c609719bSwdenk	# cd /usr/pkg/cross/powerpc-netbsd/include
5015c609719bSwdenk	# mkdir powerpc
5016c609719bSwdenk	# ln -s powerpc machine
5017c609719bSwdenk	# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5018c609719bSwdenk	# ${EDIT} powerpc/ansi.h	## must remove __va_list, _BSD_VA_LIST
5019c609719bSwdenk
5020c609719bSwdenkNative builds *don't* work due to incompatibilities between native
5021c609719bSwdenkand U-Boot include files.
5022c609719bSwdenk
5023c609719bSwdenkBooting assumes that (the first part of) the image booted is a
5024c609719bSwdenkstage-2 loader which in turn loads and then invokes the kernel
5025c609719bSwdenkproper. Loader sources will eventually appear in the NetBSD source
5026c609719bSwdenktree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
50272a8af187Swdenkmeantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5028c609719bSwdenk
5029c609719bSwdenk
5030c609719bSwdenkImplementation Internals:
5031c609719bSwdenk=========================
5032c609719bSwdenk
5033c609719bSwdenkThe following is not intended to be a complete description of every
5034c609719bSwdenkimplementation detail. However, it should help to understand the
5035c609719bSwdenkinner workings of U-Boot and make it easier to port it to custom
5036c609719bSwdenkhardware.
5037c609719bSwdenk
5038c609719bSwdenk
5039c609719bSwdenkInitial Stack, Global Data:
5040c609719bSwdenk---------------------------
5041c609719bSwdenk
5042c609719bSwdenkThe implementation of U-Boot is complicated by the fact that U-Boot
5043c609719bSwdenkstarts running out of ROM (flash memory), usually without access to
5044c609719bSwdenksystem RAM (because the memory controller is not initialized yet).
5045c609719bSwdenkThis means that we don't have writable Data or BSS segments, and BSS
5046c609719bSwdenkis not initialized as zero. To be able to get a C environment working
5047c609719bSwdenkat all, we have to allocate at least a minimal stack. Implementation
5048c609719bSwdenkoptions for this are defined and restricted by the CPU used: Some CPU
5049c609719bSwdenkmodels provide on-chip memory (like the IMMR area on MPC8xx and
5050c609719bSwdenkMPC826x processors), on others (parts of) the data cache can be
5051c609719bSwdenklocked as (mis-) used as memory, etc.
5052c609719bSwdenk
50537152b1d0Swdenk	Chris Hallinan posted a good summary of these issues to the
50540668236bSWolfgang Denk	U-Boot mailing list:
505543d9616cSwdenk
505643d9616cSwdenk	Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
505743d9616cSwdenk	From: "Chris Hallinan" <clh@net1plus.com>
505843d9616cSwdenk	Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
505943d9616cSwdenk	...
506043d9616cSwdenk
506143d9616cSwdenk	Correct me if I'm wrong, folks, but the way I understand it
506243d9616cSwdenk	is this: Using DCACHE as initial RAM for Stack, etc, does not
506343d9616cSwdenk	require any physical RAM backing up the cache. The cleverness
506443d9616cSwdenk	is that the cache is being used as a temporary supply of
506543d9616cSwdenk	necessary storage before the SDRAM controller is setup. It's
506611ccc33fSMarcel Ziswiler	beyond the scope of this list to explain the details, but you
506743d9616cSwdenk	can see how this works by studying the cache architecture and
506843d9616cSwdenk	operation in the architecture and processor-specific manuals.
506943d9616cSwdenk
507043d9616cSwdenk	OCM is On Chip Memory, which I believe the 405GP has 4K. It
507143d9616cSwdenk	is another option for the system designer to use as an
507211ccc33fSMarcel Ziswiler	initial stack/RAM area prior to SDRAM being available. Either
507343d9616cSwdenk	option should work for you. Using CS 4 should be fine if your
507443d9616cSwdenk	board designers haven't used it for something that would
507543d9616cSwdenk	cause you grief during the initial boot! It is frequently not
507643d9616cSwdenk	used.
507743d9616cSwdenk
50786d0f6bcfSJean-Christophe PLAGNIOL-VILLARD	CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
507943d9616cSwdenk	with your processor/board/system design. The default value
508043d9616cSwdenk	you will find in any recent u-boot distribution in
50818a316c9bSStefan Roese	walnut.h should work for you. I'd set it to a value larger
508243d9616cSwdenk	than your SDRAM module. If you have a 64MB SDRAM module, set
508343d9616cSwdenk	it above 400_0000. Just make sure your board has no resources
508443d9616cSwdenk	that are supposed to respond to that address! That code in
508543d9616cSwdenk	start.S has been around a while and should work as is when
508643d9616cSwdenk	you get the config right.
508743d9616cSwdenk
508843d9616cSwdenk	-Chris Hallinan
508943d9616cSwdenk	DS4.COM, Inc.
509043d9616cSwdenk
5091c609719bSwdenkIt is essential to remember this, since it has some impact on the C
5092c609719bSwdenkcode for the initialization procedures:
5093c609719bSwdenk
5094c609719bSwdenk* Initialized global data (data segment) is read-only. Do not attempt
5095c609719bSwdenk  to write it.
5096c609719bSwdenk
509711ccc33fSMarcel Ziswiler* Do not use any uninitialized global data (or implicitely initialized
5098c609719bSwdenk  as zero data - BSS segment) at all - this is undefined, initiali-
50997152b1d0Swdenk  zation is performed later (when relocating to RAM).
5100c609719bSwdenk
5101c609719bSwdenk* Stack space is very limited. Avoid big data buffers or things like
5102c609719bSwdenk  that.
5103c609719bSwdenk
5104c609719bSwdenkHaving only the stack as writable memory limits means we cannot use
5105c609719bSwdenknormal global data to share information beween the code. But it
5106c609719bSwdenkturned out that the implementation of U-Boot can be greatly
5107c609719bSwdenksimplified by making a global data structure (gd_t) available to all
5108c609719bSwdenkfunctions. We could pass a pointer to this data as argument to _all_
5109c609719bSwdenkfunctions, but this would bloat the code. Instead we use a feature of
5110c609719bSwdenkthe GCC compiler (Global Register Variables) to share the data: we
5111c609719bSwdenkplace a pointer (gd) to the global data into a register which we
5112c609719bSwdenkreserve for this purpose.
5113c609719bSwdenk
51147152b1d0SwdenkWhen choosing a register for such a purpose we are restricted by the
5115c609719bSwdenkrelevant  (E)ABI  specifications for the current architecture, and by
5116c609719bSwdenkGCC's implementation.
5117c609719bSwdenk
5118c609719bSwdenkFor PowerPC, the following registers have specific use:
5119c609719bSwdenk	R1:	stack pointer
5120e7670f6cSWolfgang Denk	R2:	reserved for system use
5121c609719bSwdenk	R3-R4:	parameter passing and return values
5122c609719bSwdenk	R5-R10: parameter passing
5123c609719bSwdenk	R13:	small data area pointer
5124c609719bSwdenk	R30:	GOT pointer
5125c609719bSwdenk	R31:	frame pointer
5126c609719bSwdenk
5127e6bee808SJoakim Tjernlund	(U-Boot also uses R12 as internal GOT pointer. r12
5128e6bee808SJoakim Tjernlund	is a volatile register so r12 needs to be reset when
5129e6bee808SJoakim Tjernlund	going back and forth between asm and C)
5130c609719bSwdenk
5131e7670f6cSWolfgang Denk    ==> U-Boot will use R2 to hold a pointer to the global data
5132c609719bSwdenk
5133c609719bSwdenk    Note: on PPC, we could use a static initializer (since the
5134c609719bSwdenk    address of the global data structure is known at compile time),
5135c609719bSwdenk    but it turned out that reserving a register results in somewhat
5136c609719bSwdenk    smaller code - although the code savings are not that big (on
5137c609719bSwdenk    average for all boards 752 bytes for the whole U-Boot image,
5138c609719bSwdenk    624 text + 127 data).
5139c609719bSwdenk
5140c4db335cSRobin GetzOn Blackfin, the normal C ABI (except for P3) is followed as documented here:
51414c58eb55SMike Frysinger	http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
51424c58eb55SMike Frysinger
5143c4db335cSRobin Getz    ==> U-Boot will use P3 to hold a pointer to the global data
51444c58eb55SMike Frysinger
5145c609719bSwdenkOn ARM, the following registers are used:
5146c609719bSwdenk
5147c609719bSwdenk	R0:	function argument word/integer result
5148c609719bSwdenk	R1-R3:	function argument word
5149c609719bSwdenk	R9:	GOT pointer
5150c609719bSwdenk	R10:	stack limit (used only if stack checking if enabled)
5151c609719bSwdenk	R11:	argument (frame) pointer
5152c609719bSwdenk	R12:	temporary workspace
5153c609719bSwdenk	R13:	stack pointer
5154c609719bSwdenk	R14:	link register
5155c609719bSwdenk	R15:	program counter
5156c609719bSwdenk
5157c609719bSwdenk    ==> U-Boot will use R8 to hold a pointer to the global data
5158c609719bSwdenk
51590df01fd3SThomas ChouOn Nios II, the ABI is documented here:
51600df01fd3SThomas Chou	http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
51610df01fd3SThomas Chou
51620df01fd3SThomas Chou    ==> U-Boot will use gp to hold a pointer to the global data
51630df01fd3SThomas Chou
51640df01fd3SThomas Chou    Note: on Nios II, we give "-G0" option to gcc and don't use gp
51650df01fd3SThomas Chou    to access small data sections, so gp is free.
51660df01fd3SThomas Chou
5167afc1ce82SMacpaul LinOn NDS32, the following registers are used:
5168afc1ce82SMacpaul Lin
5169afc1ce82SMacpaul Lin	R0-R1:	argument/return
5170afc1ce82SMacpaul Lin	R2-R5:	argument
5171afc1ce82SMacpaul Lin	R15:	temporary register for assembler
5172afc1ce82SMacpaul Lin	R16:	trampoline register
5173afc1ce82SMacpaul Lin	R28:	frame pointer (FP)
5174afc1ce82SMacpaul Lin	R29:	global pointer (GP)
5175afc1ce82SMacpaul Lin	R30:	link register (LP)
5176afc1ce82SMacpaul Lin	R31:	stack pointer (SP)
5177afc1ce82SMacpaul Lin	PC:	program counter (PC)
5178afc1ce82SMacpaul Lin
5179afc1ce82SMacpaul Lin    ==> U-Boot will use R10 to hold a pointer to the global data
5180afc1ce82SMacpaul Lin
5181d87080b7SWolfgang DenkNOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5182d87080b7SWolfgang Denkor current versions of GCC may "optimize" the code too much.
5183c609719bSwdenk
5184c609719bSwdenkMemory Management:
5185c609719bSwdenk------------------
5186c609719bSwdenk
5187c609719bSwdenkU-Boot runs in system state and uses physical addresses, i.e. the
5188c609719bSwdenkMMU is not used either for address mapping nor for memory protection.
5189c609719bSwdenk
5190c609719bSwdenkThe available memory is mapped to fixed addresses using the memory
5191c609719bSwdenkcontroller. In this process, a contiguous block is formed for each
5192c609719bSwdenkmemory type (Flash, SDRAM, SRAM), even when it consists of several
5193c609719bSwdenkphysical memory banks.
5194c609719bSwdenk
5195c609719bSwdenkU-Boot is installed in the first 128 kB of the first Flash bank (on
5196c609719bSwdenkTQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5197c609719bSwdenkbooting and sizing and initializing DRAM, the code relocates itself
5198c609719bSwdenkto the upper end of DRAM. Immediately below the U-Boot code some
51996d0f6bcfSJean-Christophe PLAGNIOL-VILLARDmemory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5200c609719bSwdenkconfiguration setting]. Below that, a structure with global Board
5201c609719bSwdenkInfo data is placed, followed by the stack (growing downward).
5202c609719bSwdenk
5203c609719bSwdenkAdditionally, some exception handler code is copied to the low 8 kB
5204c609719bSwdenkof DRAM (0x00000000 ... 0x00001FFF).
5205c609719bSwdenk
5206c609719bSwdenkSo a typical memory configuration with 16 MB of DRAM could look like
5207c609719bSwdenkthis:
5208c609719bSwdenk
5209c609719bSwdenk	0x0000 0000	Exception Vector code
5210c609719bSwdenk	      :
5211c609719bSwdenk	0x0000 1FFF
5212c609719bSwdenk	0x0000 2000	Free for Application Use
5213c609719bSwdenk	      :
5214c609719bSwdenk	      :
5215c609719bSwdenk
5216c609719bSwdenk	      :
5217c609719bSwdenk	      :
5218c609719bSwdenk	0x00FB FF20	Monitor Stack (Growing downward)
5219c609719bSwdenk	0x00FB FFAC	Board Info Data and permanent copy of global data
5220c609719bSwdenk	0x00FC 0000	Malloc Arena
5221c609719bSwdenk	      :
5222c609719bSwdenk	0x00FD FFFF
5223c609719bSwdenk	0x00FE 0000	RAM Copy of Monitor Code
5224c609719bSwdenk	...		eventually: LCD or video framebuffer
5225c609719bSwdenk	...		eventually: pRAM (Protected RAM - unchanged by reset)
5226c609719bSwdenk	0x00FF FFFF	[End of RAM]
5227c609719bSwdenk
5228c609719bSwdenk
5229c609719bSwdenkSystem Initialization:
5230c609719bSwdenk----------------------
5231c609719bSwdenk
5232c609719bSwdenkIn the reset configuration, U-Boot starts at the reset entry point
523311ccc33fSMarcel Ziswiler(on most PowerPC systems at address 0x00000100). Because of the reset
5234c609719bSwdenkconfiguration for CS0# this is a mirror of the onboard Flash memory.
52357152b1d0SwdenkTo be able to re-map memory U-Boot then jumps to its link address.
5236c609719bSwdenkTo be able to implement the initialization code in C, a (small!)
5237c609719bSwdenkinitial stack is set up in the internal Dual Ported RAM (in case CPUs
5238c609719bSwdenkwhich provide such a feature like MPC8xx or MPC8260), or in a locked
5239c609719bSwdenkpart of the data cache. After that, U-Boot initializes the CPU core,
5240c609719bSwdenkthe caches and the SIU.
5241c609719bSwdenk
5242c609719bSwdenkNext, all (potentially) available memory banks are mapped using a
5243c609719bSwdenkpreliminary mapping. For example, we put them on 512 MB boundaries
5244c609719bSwdenk(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5245c609719bSwdenkon 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5246c609719bSwdenkprogrammed for SDRAM access. Using the temporary configuration, a
5247c609719bSwdenksimple memory test is run that determines the size of the SDRAM
5248c609719bSwdenkbanks.
5249c609719bSwdenk
5250c609719bSwdenkWhen there is more than one SDRAM bank, and the banks are of
52517152b1d0Swdenkdifferent size, the largest is mapped first. For equal size, the first
5252c609719bSwdenkbank (CS2#) is mapped first. The first mapping is always for address
5253c609719bSwdenk0x00000000, with any additional banks following immediately to create
5254c609719bSwdenkcontiguous memory starting from 0.
5255c609719bSwdenk
5256c609719bSwdenkThen, the monitor installs itself at the upper end of the SDRAM area
5257c609719bSwdenkand allocates memory for use by malloc() and for the global Board
5258c609719bSwdenkInfo data; also, the exception vector code is copied to the low RAM
5259c609719bSwdenkpages, and the final stack is set up.
5260c609719bSwdenk
5261c609719bSwdenkOnly after this relocation will you have a "normal" C environment;
5262c609719bSwdenkuntil that you are restricted in several ways, mostly because you are
5263c609719bSwdenkrunning from ROM, and because the code will have to be relocated to a
5264c609719bSwdenknew address in RAM.
5265c609719bSwdenk
5266c609719bSwdenk
5267c609719bSwdenkU-Boot Porting Guide:
5268c609719bSwdenk----------------------
5269c609719bSwdenk
5270c609719bSwdenk[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
52716aff3115Swdenklist, October 2002]
5272c609719bSwdenk
5273c609719bSwdenk
5274c609719bSwdenkint main(int argc, char *argv[])
5275c609719bSwdenk{
5276c609719bSwdenk	sighandler_t no_more_time;
5277c609719bSwdenk
5278c609719bSwdenk	signal(SIGALRM, no_more_time);
5279c609719bSwdenk	alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5280c609719bSwdenk
5281c609719bSwdenk	if (available_money > available_manpower) {
52826c3fef28SJerry Van Baren		Pay consultant to port U-Boot;
5283c609719bSwdenk		return 0;
5284c609719bSwdenk	}
5285c609719bSwdenk
5286c609719bSwdenk	Download latest U-Boot source;
5287c609719bSwdenk
52880668236bSWolfgang Denk	Subscribe to u-boot mailing list;
52896aff3115Swdenk
52906c3fef28SJerry Van Baren	if (clueless)
5291c609719bSwdenk		email("Hi, I am new to U-Boot, how do I get started?");
5292c609719bSwdenk
5293c609719bSwdenk	while (learning) {
5294c609719bSwdenk		Read the README file in the top level directory;
52957cb22f97Swdenk		Read http://www.denx.de/twiki/bin/view/DULG/Manual;
52966c3fef28SJerry Van Baren		Read applicable doc/*.README;
5297c609719bSwdenk		Read the source, Luke;
52986c3fef28SJerry Van Baren		/* find . -name "*.[chS]" | xargs grep -i <keyword> */
5299c609719bSwdenk	}
5300c609719bSwdenk
53016c3fef28SJerry Van Baren	if (available_money > toLocalCurrency ($2500))
53026c3fef28SJerry Van Baren		Buy a BDI3000;
53036c3fef28SJerry Van Baren	else
5304c609719bSwdenk		Add a lot of aggravation and time;
5305c609719bSwdenk
53066c3fef28SJerry Van Baren	if (a similar board exists) {	/* hopefully... */
53076c3fef28SJerry Van Baren		cp -a board/<similar> board/<myboard>
53086c3fef28SJerry Van Baren		cp include/configs/<similar>.h include/configs/<myboard>.h
53096c3fef28SJerry Van Baren	} else {
5310c609719bSwdenk		Create your own board support subdirectory;
53116c3fef28SJerry Van Baren		Create your own board include/configs/<myboard>.h file;
53126c3fef28SJerry Van Baren	}
53136c3fef28SJerry Van Baren	Edit new board/<myboard> files
53146c3fef28SJerry Van Baren	Edit new include/configs/<myboard>.h
5315c609719bSwdenk
53166c3fef28SJerry Van Baren	while (!accepted) {
5317c609719bSwdenk		while (!running) {
5318c609719bSwdenk			do {
5319c609719bSwdenk				Add / modify source code;
5320c609719bSwdenk			} until (compiles);
5321c609719bSwdenk			Debug;
5322c609719bSwdenk			if (clueless)
5323c609719bSwdenk				email("Hi, I am having problems...");
5324c609719bSwdenk		}
53256c3fef28SJerry Van Baren		Send patch file to the U-Boot email list;
53266c3fef28SJerry Van Baren		if (reasonable critiques)
53276c3fef28SJerry Van Baren			Incorporate improvements from email list code review;
53286c3fef28SJerry Van Baren		else
53296c3fef28SJerry Van Baren			Defend code as written;
53306c3fef28SJerry Van Baren	}
5331c609719bSwdenk
5332c609719bSwdenk	return 0;
5333c609719bSwdenk}
5334c609719bSwdenk
5335c609719bSwdenkvoid no_more_time (int sig)
5336c609719bSwdenk{
5337c609719bSwdenk      hire_a_guru();
5338c609719bSwdenk}
5339c609719bSwdenk
5340c609719bSwdenk
5341c609719bSwdenkCoding Standards:
5342c609719bSwdenk-----------------
5343c609719bSwdenk
5344c609719bSwdenkAll contributions to U-Boot should conform to the Linux kernel
53452c051651SDetlev Zundelcoding style; see the file "Documentation/CodingStyle" and the script
53467ca9296eSWolfgang Denk"scripts/Lindent" in your Linux kernel source directory.
5347c609719bSwdenk
53482c051651SDetlev ZundelSource files originating from a different project (for example the
53492c051651SDetlev ZundelMTD subsystem) are generally exempt from these guidelines and are not
53502c051651SDetlev Zundelreformated to ease subsequent migration to newer versions of those
53512c051651SDetlev Zundelsources.
53522c051651SDetlev Zundel
53532c051651SDetlev ZundelPlease note that U-Boot is implemented in C (and to some small parts in
53542c051651SDetlev ZundelAssembler); no C++ is used, so please do not use C++ style comments (//)
53552c051651SDetlev Zundelin your code.
5356c609719bSwdenk
5357c178d3daSwdenkPlease also stick to the following formatting rules:
5358180d3f74Swdenk- remove any trailing white space
53597ca9296eSWolfgang Denk- use TAB characters for indentation and vertical alignment, not spaces
5360180d3f74Swdenk- make sure NOT to use DOS '\r\n' line feeds
53617ca9296eSWolfgang Denk- do not add more than 2 consecutive empty lines to source files
5362180d3f74Swdenk- do not add trailing empty lines to source files
5363180d3f74Swdenk
5364c609719bSwdenkSubmissions which do not conform to the standards may be returned
5365c609719bSwdenkwith a request to reformat the changes.
5366c609719bSwdenk
5367c609719bSwdenk
5368c609719bSwdenkSubmitting Patches:
5369c609719bSwdenk-------------------
5370c609719bSwdenk
5371c609719bSwdenkSince the number of patches for U-Boot is growing, we need to
5372c609719bSwdenkestablish some rules. Submissions which do not conform to these rules
5373c609719bSwdenkmay be rejected, even when they contain important and valuable stuff.
5374c609719bSwdenk
53750d28f34bSMagnus LiljaPlease see http://www.denx.de/wiki/U-Boot/Patches for details.
5376218ca724SWolfgang Denk
53770668236bSWolfgang DenkPatches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
53780668236bSWolfgang Denksee http://lists.denx.de/mailman/listinfo/u-boot
53790668236bSWolfgang Denk
5380c609719bSwdenkWhen you send a patch, please include the following information with
5381c609719bSwdenkit:
5382c609719bSwdenk
5383c609719bSwdenk* For bug fixes: a description of the bug and how your patch fixes
5384c609719bSwdenk  this bug. Please try to include a way of demonstrating that the
5385c609719bSwdenk  patch actually fixes something.
5386c609719bSwdenk
5387c609719bSwdenk* For new features: a description of the feature and your
5388c609719bSwdenk  implementation.
5389c609719bSwdenk
5390c609719bSwdenk* A CHANGELOG entry as plaintext (separate from the patch)
5391c609719bSwdenk
5392c609719bSwdenk* For major contributions, your entry to the CREDITS file
5393c609719bSwdenk
5394c609719bSwdenk* When you add support for a new board, don't forget to add this
53957ca9296eSWolfgang Denk  board to the MAINTAINERS file, too.
5396c609719bSwdenk
5397c609719bSwdenk* If your patch adds new configuration options, don't forget to
5398c609719bSwdenk  document these in the README file.
5399c609719bSwdenk
5400218ca724SWolfgang Denk* The patch itself. If you are using git (which is *strongly*
5401218ca724SWolfgang Denk  recommended) you can easily generate the patch using the
54027ca9296eSWolfgang Denk  "git format-patch". If you then use "git send-email" to send it to
5403218ca724SWolfgang Denk  the U-Boot mailing list, you will avoid most of the common problems
5404218ca724SWolfgang Denk  with some other mail clients.
5405c609719bSwdenk
5406218ca724SWolfgang Denk  If you cannot use git, use "diff -purN OLD NEW". If your version of
5407218ca724SWolfgang Denk  diff does not support these options, then get the latest version of
5408218ca724SWolfgang Denk  GNU diff.
54096dff5529Swdenk
5410218ca724SWolfgang Denk  The current directory when running this command shall be the parent
5411218ca724SWolfgang Denk  directory of the U-Boot source tree (i. e. please make sure that
5412218ca724SWolfgang Denk  your patch includes sufficient directory information for the
5413218ca724SWolfgang Denk  affected files).
5414218ca724SWolfgang Denk
5415218ca724SWolfgang Denk  We prefer patches as plain text. MIME attachments are discouraged,
5416218ca724SWolfgang Denk  and compressed attachments must not be used.
5417c609719bSwdenk
541852f52c14Swdenk* If one logical set of modifications affects or creates several
541952f52c14Swdenk  files, all these changes shall be submitted in a SINGLE patch file.
542052f52c14Swdenk
542152f52c14Swdenk* Changesets that contain different, unrelated modifications shall be
542252f52c14Swdenk  submitted as SEPARATE patches, one patch per changeset.
542352f52c14Swdenk
542452f52c14Swdenk
5425c609719bSwdenkNotes:
5426c609719bSwdenk
5427c609719bSwdenk* Before sending the patch, run the MAKEALL script on your patched
5428c609719bSwdenk  source tree and make sure that no errors or warnings are reported
5429c609719bSwdenk  for any of the boards.
5430c609719bSwdenk
5431c609719bSwdenk* Keep your modifications to the necessary minimum: A patch
5432c609719bSwdenk  containing several unrelated changes or arbitrary reformats will be
5433c609719bSwdenk  returned with a request to re-formatting / split it.
5434c609719bSwdenk
5435c609719bSwdenk* If you modify existing code, make sure that your new code does not
5436c609719bSwdenk  add to the memory footprint of the code ;-) Small is beautiful!
5437c609719bSwdenk  When adding new features, these should compile conditionally only
5438c609719bSwdenk  (using #ifdef), and the resulting code with the new feature
5439c609719bSwdenk  disabled must not need more memory than the old code without your
5440c609719bSwdenk  modification.
544190dc6704Swdenk
54420668236bSWolfgang Denk* Remember that there is a size limit of 100 kB per message on the
54430668236bSWolfgang Denk  u-boot mailing list. Bigger patches will be moderated. If they are
54440668236bSWolfgang Denk  reasonable and not too big, they will be acknowledged. But patches
54450668236bSWolfgang Denk  bigger than the size limit should be avoided.
5446