xref: /openbmc/u-boot/README (revision 5e12e75d17c4b15a310a45cd78fe71b7698a8a8e)
1c609719bSwdenk#
2218ca724SWolfgang Denk# (C) Copyright 2000 - 2008
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
57c609719bSwdenk
58c609719bSwdenkWhere to get help:
59c609719bSwdenk==================
60c609719bSwdenk
61c609719bSwdenkIn case you have questions about, problems with or contributions for
62c609719bSwdenkU-Boot you should send a message to the U-Boot mailing list at
63c609719bSwdenk<u-boot-users@lists.sourceforge.net>. There is also an archive of
64c609719bSwdenkprevious traffic on the mailing list - please search the archive
65c609719bSwdenkbefore asking FAQ's. Please see
66c609719bSwdenkhttp://lists.sourceforge.net/lists/listinfo/u-boot-users/
67c609719bSwdenk
68c609719bSwdenk
69218ca724SWolfgang DenkWhere to get source code:
70218ca724SWolfgang Denk=========================
71218ca724SWolfgang Denk
72218ca724SWolfgang DenkThe U-Boot source code is maintained in the git repository at
73218ca724SWolfgang Denkgit://www.denx.de/git/u-boot.git ; you can browse it online at
74218ca724SWolfgang Denkhttp://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
75218ca724SWolfgang Denk
76218ca724SWolfgang DenkThe "snapshot" links on this page allow you to download tarballs of
77218ca724SWolfgang Denkany version you might be interested in. Ofifcial releases are also
78218ca724SWolfgang Denkavailable for FTP download from the ftp://ftp.denx.de/pub/u-boot/
79218ca724SWolfgang Denkdirectory.
80218ca724SWolfgang Denk
81d4ee711dSAnatolij GustschinPre-built (and tested) images are available from
82218ca724SWolfgang Denkftp://ftp.denx.de/pub/u-boot/images/
83218ca724SWolfgang Denk
84218ca724SWolfgang Denk
85c609719bSwdenkWhere we come from:
86c609719bSwdenk===================
87c609719bSwdenk
88c609719bSwdenk- start from 8xxrom sources
8924ee89b9Swdenk- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
90c609719bSwdenk- clean up code
91c609719bSwdenk- make it easier to add custom boards
92c609719bSwdenk- make it possible to add other [PowerPC] CPUs
93c609719bSwdenk- extend functions, especially:
94c609719bSwdenk  * Provide extended interface to Linux boot loader
95c609719bSwdenk  * S-Record download
96c609719bSwdenk  * network boot
97c609719bSwdenk  * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
9824ee89b9Swdenk- create ARMBoot project (http://sourceforge.net/projects/armboot)
99c609719bSwdenk- add other CPU families (starting with ARM)
10024ee89b9Swdenk- create U-Boot project (http://sourceforge.net/projects/u-boot)
101218ca724SWolfgang Denk- current project page: see http://www.denx.de/wiki/UBoot
10224ee89b9Swdenk
10324ee89b9Swdenk
10424ee89b9SwdenkNames and Spelling:
10524ee89b9Swdenk===================
10624ee89b9Swdenk
10724ee89b9SwdenkThe "official" name of this project is "Das U-Boot". The spelling
10824ee89b9Swdenk"U-Boot" shall be used in all written text (documentation, comments
10924ee89b9Swdenkin source files etc.). Example:
11024ee89b9Swdenk
11124ee89b9Swdenk	This is the README file for the U-Boot project.
11224ee89b9Swdenk
11324ee89b9SwdenkFile names etc. shall be based on the string "u-boot". Examples:
11424ee89b9Swdenk
11524ee89b9Swdenk	include/asm-ppc/u-boot.h
11624ee89b9Swdenk
11724ee89b9Swdenk	#include <asm/u-boot.h>
11824ee89b9Swdenk
11924ee89b9SwdenkVariable names, preprocessor constants etc. shall be either based on
12024ee89b9Swdenkthe string "u_boot" or on "U_BOOT". Example:
12124ee89b9Swdenk
12224ee89b9Swdenk	U_BOOT_VERSION		u_boot_logo
12324ee89b9Swdenk	IH_OS_U_BOOT		u_boot_hush_start
124c609719bSwdenk
125c609719bSwdenk
12693f19cc0SwdenkVersioning:
12793f19cc0Swdenk===========
12893f19cc0Swdenk
12993f19cc0SwdenkU-Boot uses a 3 level version number containing a version, a
13093f19cc0Swdenksub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
13193f19cc0Swdenksub-version "34", and patchlevel "4".
13293f19cc0Swdenk
13393f19cc0SwdenkThe patchlevel is used to indicate certain stages of development
13493f19cc0Swdenkbetween released versions, i. e. officially released versions of
13593f19cc0SwdenkU-Boot will always have a patchlevel of "0".
13693f19cc0Swdenk
13793f19cc0Swdenk
138c609719bSwdenkDirectory Hierarchy:
139c609719bSwdenk====================
140c609719bSwdenk
1417152b1d0Swdenk- board		Board dependent files
1427152b1d0Swdenk- common	Misc architecture independent functions
143c609719bSwdenk- cpu		CPU specific files
144983fda83Swdenk  - 74xx_7xx	Files specific to Freescale MPC74xx and 7xx CPUs
14511dadd54Swdenk  - arm720t	Files specific to ARM 720 CPUs
14611dadd54Swdenk  - arm920t	Files specific to ARM 920 CPUs
147a85f9f21Swdenk    - at91rm9200 Files specific to Atmel AT91RM9200 CPU
148983fda83Swdenk    - imx	Files specific to Freescale MC9328 i.MX CPUs
1491d9f4105Swdenk    - s3c24x0	Files specific to Samsung S3C24X0 CPUs
15011dadd54Swdenk  - arm925t	Files specific to ARM 925 CPUs
15111dadd54Swdenk  - arm926ejs	Files specific to ARM 926 CPUs
1528ed96046Swdenk  - arm1136	Files specific to ARM 1136 CPUs
15372a087e0SWolfgang Denk  - at32ap	Files specific to Atmel AVR32 AP CPUs
15411dadd54Swdenk  - i386	Files specific to i386 CPUs
15511dadd54Swdenk  - ixp		Files specific to Intel XScale IXP CPUs
156983fda83Swdenk  - mcf52x2	Files specific to Freescale ColdFire MCF52x2 CPUs
1571552af70STsiChungLiew  - mcf5227x	Files specific to Freescale ColdFire MCF5227x CPUs
1588e585f02STsiChung Liew  - mcf532x	Files specific to Freescale ColdFire MCF5329 CPUs
1598ae158cdSTsiChungLiew  - mcf5445x	Files specific to Freescale ColdFire MCF5445x CPUs
16057a12720STsiChungLiew  - mcf547x_8x	Files specific to Freescale ColdFire MCF547x_8x CPUs
16111dadd54Swdenk  - mips	Files specific to MIPS CPUs
162983fda83Swdenk  - mpc5xx	Files specific to Freescale MPC5xx  CPUs
163983fda83Swdenk  - mpc5xxx	Files specific to Freescale MPC5xxx CPUs
164983fda83Swdenk  - mpc8xx	Files specific to Freescale MPC8xx  CPUs
165983fda83Swdenk  - mpc8220	Files specific to Freescale MPC8220 CPUs
166983fda83Swdenk  - mpc824x	Files specific to Freescale MPC824x CPUs
167983fda83Swdenk  - mpc8260	Files specific to Freescale MPC8260 CPUs
168983fda83Swdenk  - mpc85xx	Files specific to Freescale MPC85xx CPUs
16911dadd54Swdenk  - nios	Files specific to Altera NIOS CPUs
1705c952cf0Swdenk  - nios2	Files specific to Altera Nios-II CPUs
1710c8721a4SWolfgang Denk  - ppc4xx	Files specific to AMCC PowerPC 4xx CPUs
17211dadd54Swdenk  - pxa		Files specific to Intel XScale PXA CPUs
17311dadd54Swdenk  - s3c44b0	Files specific to Samsung S3C44B0 CPUs
17411dadd54Swdenk  - sa1100	Files specific to Intel StrongARM SA1100 CPUs
175c609719bSwdenk- disk		Code for disk drive partition handling
176c609719bSwdenk- doc		Documentation (don't expect too much)
1777152b1d0Swdenk- drivers	Commonly used device drivers
178c609719bSwdenk- dtt		Digital Thermometer and Thermostat drivers
179c609719bSwdenk- examples	Example code for standalone applications, etc.
180c609719bSwdenk- include	Header Files
18111dadd54Swdenk- lib_arm	Files generic to ARM	 architecture
1827b64fef3SWolfgang Denk- lib_avr32	Files generic to AVR32	 architecture
18311dadd54Swdenk- lib_generic	Files generic to all	 architectures
18411dadd54Swdenk- lib_i386	Files generic to i386	 architecture
18511dadd54Swdenk- lib_m68k	Files generic to m68k	 architecture
18611dadd54Swdenk- lib_mips	Files generic to MIPS	 architecture
18711dadd54Swdenk- lib_nios	Files generic to NIOS	 architecture
18811dadd54Swdenk- lib_ppc	Files generic to PowerPC architecture
189213bf8c8SGerald Van Baren- libfdt	Library files to support flattened device trees
190c609719bSwdenk- net		Networking code
191c609719bSwdenk- post		Power On Self Test
192c609719bSwdenk- rtc		Real Time Clock drivers
193c609719bSwdenk- tools		Tools to build S-Record or U-Boot images, etc.
194c609719bSwdenk
195c609719bSwdenkSoftware Configuration:
196c609719bSwdenk=======================
197c609719bSwdenk
198c609719bSwdenkConfiguration is usually done using C preprocessor defines; the
199c609719bSwdenkrationale behind that is to avoid dead code whenever possible.
200c609719bSwdenk
201c609719bSwdenkThere are two classes of configuration variables:
202c609719bSwdenk
203c609719bSwdenk* Configuration _OPTIONS_:
204c609719bSwdenk  These are selectable by the user and have names beginning with
205c609719bSwdenk  "CONFIG_".
206c609719bSwdenk
207c609719bSwdenk* Configuration _SETTINGS_:
208c609719bSwdenk  These depend on the hardware etc. and should not be meddled with if
209c609719bSwdenk  you don't know what you're doing; they have names beginning with
210c609719bSwdenk  "CFG_".
211c609719bSwdenk
212c609719bSwdenkLater we will add a configuration tool - probably similar to or even
213c609719bSwdenkidentical to what's used for the Linux kernel. Right now, we have to
214c609719bSwdenkdo the configuration by hand, which means creating some symbolic
215c609719bSwdenklinks and editing some configuration files. We use the TQM8xxL boards
216c609719bSwdenkas an example here.
217c609719bSwdenk
218c609719bSwdenk
219c609719bSwdenkSelection of Processor Architecture and Board Type:
220c609719bSwdenk---------------------------------------------------
221c609719bSwdenk
222c609719bSwdenkFor all supported boards there are ready-to-use default
223c609719bSwdenkconfigurations available; just type "make <board_name>_config".
224c609719bSwdenk
225c609719bSwdenkExample: For a TQM823L module type:
226c609719bSwdenk
227c609719bSwdenk	cd u-boot
228c609719bSwdenk	make TQM823L_config
229c609719bSwdenk
230c609719bSwdenkFor the Cogent platform, you need to specify the cpu type as well;
231c609719bSwdenke.g. "make cogent_mpc8xx_config". And also configure the cogent
232c609719bSwdenkdirectory according to the instructions in cogent/README.
233c609719bSwdenk
234c609719bSwdenk
235c609719bSwdenkConfiguration Options:
236c609719bSwdenk----------------------
237c609719bSwdenk
238c609719bSwdenkConfiguration depends on the combination of board and CPU type; all
239c609719bSwdenksuch information is kept in a configuration file
240c609719bSwdenk"include/configs/<board_name>.h".
241c609719bSwdenk
242c609719bSwdenkExample: For a TQM823L module, all configuration settings are in
243c609719bSwdenk"include/configs/TQM823L.h".
244c609719bSwdenk
245c609719bSwdenk
2467f6c2cbcSwdenkMany of the options are named exactly as the corresponding Linux
2477f6c2cbcSwdenkkernel configuration options. The intention is to make it easier to
2487f6c2cbcSwdenkbuild a config tool - later.
2497f6c2cbcSwdenk
2507f6c2cbcSwdenk
251c609719bSwdenkThe following options need to be configured:
252c609719bSwdenk
2532628114eSKim Phillips- CPU Type:	Define exactly one, e.g. CONFIG_MPC85XX.
254c609719bSwdenk
2552628114eSKim Phillips- Board Type:	Define exactly one, e.g. CONFIG_MPC8540ADS.
2566ccec449SWolfgang Denk
2576ccec449SWolfgang Denk- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
25809ea0de0SHaavard Skinnemoen		Define exactly one, e.g. CONFIG_ATSTK1002
259c609719bSwdenk
260c609719bSwdenk- CPU Module Type: (if CONFIG_COGENT is defined)
261c609719bSwdenk		Define exactly one of
262c609719bSwdenk		CONFIG_CMA286_60_OLD
263c609719bSwdenk--- FIXME --- not tested yet:
264c609719bSwdenk		CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
265c609719bSwdenk		CONFIG_CMA287_23, CONFIG_CMA287_50
266c609719bSwdenk
267c609719bSwdenk- Motherboard Type: (if CONFIG_COGENT is defined)
268c609719bSwdenk		Define exactly one of
269c609719bSwdenk		CONFIG_CMA101, CONFIG_CMA102
270c609719bSwdenk
271c609719bSwdenk- Motherboard I/O Modules: (if CONFIG_COGENT is defined)
272c609719bSwdenk		Define one or more of
273c609719bSwdenk		CONFIG_CMA302
274c609719bSwdenk
275c609719bSwdenk- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
276c609719bSwdenk		Define one or more of
277c609719bSwdenk		CONFIG_LCD_HEARTBEAT	- update a character position on
278c609719bSwdenk					  the lcd display every second with
279c609719bSwdenk					  a "rotator" |\-/|\-/
280c609719bSwdenk
2812535d602Swdenk- Board flavour: (if CONFIG_MPC8260ADS is defined)
2822535d602Swdenk		CONFIG_ADSTYPE
2832535d602Swdenk		Possible values are:
2842535d602Swdenk			CFG_8260ADS	- original MPC8260ADS
285180d3f74Swdenk			CFG_8266ADS	- MPC8266ADS
28654387ac9Swdenk			CFG_PQ2FADS	- PQ2FADS-ZU or PQ2FADS-VR
28704a85b3bSwdenk			CFG_8272ADS	- MPC8272ADS
2882535d602Swdenk
289c609719bSwdenk- MPC824X Family Member (if CONFIG_MPC824X is defined)
290c609719bSwdenk		Define exactly one of
291c609719bSwdenk		CONFIG_MPC8240, CONFIG_MPC8245
292c609719bSwdenk
29375d1ea7fSwdenk- 8xx CPU Options: (if using an MPC8xx cpu)
29466ca92a5Swdenk		CONFIG_8xx_GCLK_FREQ	- deprecated: CPU clock if
29566ca92a5Swdenk					  get_gclk_freq() cannot work
2965da627a4Swdenk					  e.g. if there is no 32KHz
2975da627a4Swdenk					  reference PIT/RTC clock
29866ca92a5Swdenk		CONFIG_8xx_OSCLK	- PLL input clock (either EXTCLK
29966ca92a5Swdenk					  or XTAL/EXTAL)
300c609719bSwdenk
30166ca92a5Swdenk- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
30266ca92a5Swdenk		CFG_8xx_CPUCLK_MIN
30366ca92a5Swdenk		CFG_8xx_CPUCLK_MAX
30466ca92a5Swdenk		CONFIG_8xx_CPUCLK_DEFAULT
30575d1ea7fSwdenk			See doc/README.MPC866
30675d1ea7fSwdenk
30775d1ea7fSwdenk		CFG_MEASURE_CPUCLK
30875d1ea7fSwdenk
30975d1ea7fSwdenk		Define this to measure the actual CPU clock instead
31075d1ea7fSwdenk		of relying on the correctness of the configured
31175d1ea7fSwdenk		values. Mostly useful for board bringup to make sure
31275d1ea7fSwdenk		the PLL is locked at the intended frequency. Note
31375d1ea7fSwdenk		that this requires a (stable) reference clock (32 kHz
31466ca92a5Swdenk		RTC clock or CFG_8XX_XIN)
31575d1ea7fSwdenk
3160b953ffcSMarkus Klotzbuecher- Intel Monahans options:
3170b953ffcSMarkus Klotzbuecher		CFG_MONAHANS_RUN_MODE_OSC_RATIO
3180b953ffcSMarkus Klotzbuecher
3190b953ffcSMarkus Klotzbuecher		Defines the Monahans run mode to oscillator
3200b953ffcSMarkus Klotzbuecher		ratio. Valid values are 8, 16, 24, 31. The core
3210b953ffcSMarkus Klotzbuecher		frequency is this value multiplied by 13 MHz.
3220b953ffcSMarkus Klotzbuecher
3230b953ffcSMarkus Klotzbuecher		CFG_MONAHANS_TURBO_RUN_MODE_RATIO
3240b953ffcSMarkus Klotzbuecher
3250b953ffcSMarkus Klotzbuecher		Defines the Monahans turbo mode to oscillator
3260b953ffcSMarkus Klotzbuecher		ratio. Valid values are 1 (default if undefined) and
3270b953ffcSMarkus Klotzbuecher		2. The core frequency as calculated above is multiplied
3280b953ffcSMarkus Klotzbuecher		by this value.
3290b953ffcSMarkus Klotzbuecher
3305da627a4Swdenk- Linux Kernel Interface:
331c609719bSwdenk		CONFIG_CLOCKS_IN_MHZ
332c609719bSwdenk
333c609719bSwdenk		U-Boot stores all clock information in Hz
334c609719bSwdenk		internally. For binary compatibility with older Linux
335c609719bSwdenk		kernels (which expect the clocks passed in the
336c609719bSwdenk		bd_info data to be in MHz) the environment variable
337c609719bSwdenk		"clocks_in_mhz" can be defined so that U-Boot
338c609719bSwdenk		converts clock data to MHZ before passing it to the
339c609719bSwdenk		Linux kernel.
340c609719bSwdenk		When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
341c609719bSwdenk		"clocks_in_mhz=1" is automatically included in the
342c609719bSwdenk		default environment.
343c609719bSwdenk
3445da627a4Swdenk		CONFIG_MEMSIZE_IN_BYTES		[relevant for MIPS only]
3455da627a4Swdenk
3465da627a4Swdenk		When transfering memsize parameter to linux, some versions
3475da627a4Swdenk		expect it to be in bytes, others in MB.
3485da627a4Swdenk		Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
3495da627a4Swdenk
350213bf8c8SGerald Van Baren		CONFIG_OF_LIBFDT / CONFIG_OF_FLAT_TREE
351f57f70aaSWolfgang Denk
352f57f70aaSWolfgang Denk		New kernel versions are expecting firmware settings to be
353213bf8c8SGerald Van Baren		passed using flattened device trees (based on open firmware
354213bf8c8SGerald Van Baren		concepts).
355213bf8c8SGerald Van Baren
356213bf8c8SGerald Van Baren		CONFIG_OF_LIBFDT
357213bf8c8SGerald Van Baren		 * New libfdt-based support
358213bf8c8SGerald Van Baren		 * Adds the "fdt" command
3593bb342fcSKim Phillips		 * The bootm command automatically updates the fdt
360213bf8c8SGerald Van Baren
361213bf8c8SGerald Van Baren		CONFIG_OF_FLAT_TREE
362213bf8c8SGerald Van Baren		 * Deprecated, see CONFIG_OF_LIBFDT
363213bf8c8SGerald Van Baren		 * Original ft_build.c-based support
364213bf8c8SGerald Van Baren		 * Automatically modifies the dft as part of the bootm command
365213bf8c8SGerald Van Baren		 * The environment variable "disable_of", when set,
366213bf8c8SGerald Van Baren		     disables this functionality.
367f57f70aaSWolfgang Denk
368f57f70aaSWolfgang Denk		OF_CPU - The proper name of the cpus node.
369c2871f03SKumar Gala		OF_SOC - The proper name of the soc node.
370f57f70aaSWolfgang Denk		OF_TBCLK - The timebase frequency.
371c2871f03SKumar Gala		OF_STDOUT_PATH - The path to the console device
372f57f70aaSWolfgang Denk
3733bb342fcSKim Phillips		boards with QUICC Engines require OF_QE to set UCC mac addresses
3743bb342fcSKim Phillips
375e4f880edSKumar Gala		CONFIG_OF_HAS_BD_T
376e4f880edSKumar Gala
377213bf8c8SGerald Van Baren		 * CONFIG_OF_LIBFDT - enables the "fdt bd_t" command
378213bf8c8SGerald Van Baren		 * CONFIG_OF_FLAT_TREE - The resulting flat device tree
379213bf8c8SGerald Van Baren		     will have a copy of the bd_t.  Space should be
380213bf8c8SGerald Van Baren		     pre-allocated in the dts for the bd_t.
381e4f880edSKumar Gala
382e4f880edSKumar Gala		CONFIG_OF_HAS_UBOOT_ENV
383e4f880edSKumar Gala
3843bb342fcSKim Phillips		 * CONFIG_OF_LIBFDT - enables the "fdt env" command
385213bf8c8SGerald Van Baren		 * CONFIG_OF_FLAT_TREE - The resulting flat device tree
386213bf8c8SGerald Van Baren		     will have a copy of u-boot's environment variables
387e4f880edSKumar Gala
3884e253137SKumar Gala		CONFIG_OF_BOARD_SETUP
3894e253137SKumar Gala
3904e253137SKumar Gala		Board code has addition modification that it wants to make
3914e253137SKumar Gala		to the flat device tree before handing it off to the kernel
3926705d81eSwdenk
3930267768eSMatthew McClintock		CONFIG_OF_BOOT_CPU
3940267768eSMatthew McClintock
3950267768eSMatthew McClintock		This define fills in the correct boot cpu in the boot
3960267768eSMatthew McClintock		param header, the default value is zero if undefined.
3970267768eSMatthew McClintock
3986705d81eSwdenk- Serial Ports:
3996705d81eSwdenk		CFG_PL010_SERIAL
4006705d81eSwdenk
4016705d81eSwdenk		Define this if you want support for Amba PrimeCell PL010 UARTs.
4026705d81eSwdenk
4036705d81eSwdenk		CFG_PL011_SERIAL
4046705d81eSwdenk
4056705d81eSwdenk		Define this if you want support for Amba PrimeCell PL011 UARTs.
4066705d81eSwdenk
4076705d81eSwdenk		CONFIG_PL011_CLOCK
4086705d81eSwdenk
4096705d81eSwdenk		If you have Amba PrimeCell PL011 UARTs, set this variable to
4106705d81eSwdenk		the clock speed of the UARTs.
4116705d81eSwdenk
4126705d81eSwdenk		CONFIG_PL01x_PORTS
4136705d81eSwdenk
4146705d81eSwdenk		If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
4156705d81eSwdenk		define this to a list of base addresses for each (supported)
4166705d81eSwdenk		port. See e.g. include/configs/versatile.h
4176705d81eSwdenk
4186705d81eSwdenk
419c609719bSwdenk- Console Interface:
420c609719bSwdenk		Depending on board, define exactly one serial port
421c609719bSwdenk		(like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
422c609719bSwdenk		CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
423c609719bSwdenk		console by defining CONFIG_8xx_CONS_NONE
424c609719bSwdenk
425c609719bSwdenk		Note: if CONFIG_8xx_CONS_NONE is defined, the serial
426c609719bSwdenk		port routines must be defined elsewhere
427c609719bSwdenk		(i.e. serial_init(), serial_getc(), ...)
428c609719bSwdenk
429c609719bSwdenk		CONFIG_CFB_CONSOLE
430c609719bSwdenk		Enables console device for a color framebuffer. Needs following
431c609719bSwdenk		defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
432c609719bSwdenk			VIDEO_FB_LITTLE_ENDIAN	graphic memory organisation
433c609719bSwdenk						(default big endian)
434c609719bSwdenk			VIDEO_HW_RECTFILL	graphic chip supports
435c609719bSwdenk						rectangle fill
436c609719bSwdenk						(cf. smiLynxEM)
437c609719bSwdenk			VIDEO_HW_BITBLT		graphic chip supports
438c609719bSwdenk						bit-blit (cf. smiLynxEM)
439c609719bSwdenk			VIDEO_VISIBLE_COLS	visible pixel columns
440c609719bSwdenk						(cols=pitch)
441c609719bSwdenk			VIDEO_VISIBLE_ROWS	visible pixel rows
442c609719bSwdenk			VIDEO_PIXEL_SIZE	bytes per pixel
443c609719bSwdenk			VIDEO_DATA_FORMAT	graphic data format
444c609719bSwdenk						(0-5, cf. cfb_console.c)
445c609719bSwdenk			VIDEO_FB_ADRS		framebuffer address
446c609719bSwdenk			VIDEO_KBD_INIT_FCT	keyboard int fct
447c609719bSwdenk						(i.e. i8042_kbd_init())
448c609719bSwdenk			VIDEO_TSTC_FCT		test char fct
449c609719bSwdenk						(i.e. i8042_tstc)
450c609719bSwdenk			VIDEO_GETC_FCT		get char fct
451c609719bSwdenk						(i.e. i8042_getc)
452c609719bSwdenk			CONFIG_CONSOLE_CURSOR	cursor drawing on/off
453c609719bSwdenk						(requires blink timer
454c609719bSwdenk						cf. i8042.c)
455c609719bSwdenk			CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
456c609719bSwdenk			CONFIG_CONSOLE_TIME	display time/date info in
457c609719bSwdenk						upper right corner
458602ad3b3SJon Loeliger						(requires CONFIG_CMD_DATE)
459c609719bSwdenk			CONFIG_VIDEO_LOGO	display Linux logo in
460c609719bSwdenk						upper left corner
461a6c7ad2fSwdenk			CONFIG_VIDEO_BMP_LOGO	use bmp_logo.h instead of
462a6c7ad2fSwdenk						linux_logo.h for logo.
463a6c7ad2fSwdenk						Requires CONFIG_VIDEO_LOGO
464c609719bSwdenk			CONFIG_CONSOLE_EXTRA_INFO
465c609719bSwdenk						addional board info beside
466c609719bSwdenk						the logo
467c609719bSwdenk
468c609719bSwdenk		When CONFIG_CFB_CONSOLE is defined, video console is
469c609719bSwdenk		default i/o. Serial console can be forced with
470c609719bSwdenk		environment 'console=serial'.
471c609719bSwdenk
472a3ad8e26Swdenk		When CONFIG_SILENT_CONSOLE is defined, all console
473a3ad8e26Swdenk		messages (by U-Boot and Linux!) can be silenced with
474a3ad8e26Swdenk		the "silent" environment variable. See
475a3ad8e26Swdenk		doc/README.silent for more information.
476a3ad8e26Swdenk
477c609719bSwdenk- Console Baudrate:
478c609719bSwdenk		CONFIG_BAUDRATE - in bps
479c609719bSwdenk		Select one of the baudrates listed in
480c609719bSwdenk		CFG_BAUDRATE_TABLE, see below.
4813bbc899fSwdenk		CFG_BRGCLK_PRESCALE, baudrate prescale
482c609719bSwdenk
483c609719bSwdenk- Interrupt driven serial port input:
484c609719bSwdenk		CONFIG_SERIAL_SOFTWARE_FIFO
485c609719bSwdenk
486c609719bSwdenk		PPC405GP only.
487c609719bSwdenk		Use an interrupt handler for receiving data on the
488c609719bSwdenk		serial port. It also enables using hardware handshake
489c609719bSwdenk		(RTS/CTS) and UART's built-in FIFO. Set the number of
490c609719bSwdenk		bytes the interrupt driven input buffer should have.
491c609719bSwdenk
492109c0e3aSwdenk		Leave undefined to disable this feature, including
493109c0e3aSwdenk		disable the buffer and hardware handshake.
494c609719bSwdenk
4951d49b1f3Sstroese- Console UART Number:
4961d49b1f3Sstroese		CONFIG_UART1_CONSOLE
4971d49b1f3Sstroese
4980c8721a4SWolfgang Denk		AMCC PPC4xx only.
4991d49b1f3Sstroese		If defined internal UART1 (and not UART0) is used
5001d49b1f3Sstroese		as default U-Boot console.
5011d49b1f3Sstroese
502c609719bSwdenk- Boot Delay:	CONFIG_BOOTDELAY - in seconds
503c609719bSwdenk		Delay before automatically booting the default image;
504c609719bSwdenk		set to -1 to disable autoboot.
505c609719bSwdenk
506c609719bSwdenk		See doc/README.autoboot for these options that
507c609719bSwdenk		work with CONFIG_BOOTDELAY. None are required.
508c609719bSwdenk		CONFIG_BOOT_RETRY_TIME
509c609719bSwdenk		CONFIG_BOOT_RETRY_MIN
510c609719bSwdenk		CONFIG_AUTOBOOT_KEYED
511c609719bSwdenk		CONFIG_AUTOBOOT_PROMPT
512c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR
513c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR
514c609719bSwdenk		CONFIG_AUTOBOOT_DELAY_STR2
515c609719bSwdenk		CONFIG_AUTOBOOT_STOP_STR2
516c609719bSwdenk		CONFIG_ZERO_BOOTDELAY_CHECK
517c609719bSwdenk		CONFIG_RESET_TO_RETRY
518c609719bSwdenk
519c609719bSwdenk- Autoboot Command:
520c609719bSwdenk		CONFIG_BOOTCOMMAND
521c609719bSwdenk		Only needed when CONFIG_BOOTDELAY is enabled;
522c609719bSwdenk		define a command string that is automatically executed
523c609719bSwdenk		when no character is read on the console interface
524c609719bSwdenk		within "Boot Delay" after reset.
525c609719bSwdenk
526c609719bSwdenk		CONFIG_BOOTARGS
527c609719bSwdenk		This can be used to pass arguments to the bootm
528c609719bSwdenk		command. The value of CONFIG_BOOTARGS goes into the
529c609719bSwdenk		environment value "bootargs".
530c609719bSwdenk
531c609719bSwdenk		CONFIG_RAMBOOT and CONFIG_NFSBOOT
532c609719bSwdenk		The value of these goes into the environment as
533c609719bSwdenk		"ramboot" and "nfsboot" respectively, and can be used
534c609719bSwdenk		as a convenience, when switching between booting from
535c609719bSwdenk		ram and nfs.
536c609719bSwdenk
537c609719bSwdenk- Pre-Boot Commands:
538c609719bSwdenk		CONFIG_PREBOOT
539c609719bSwdenk
540c609719bSwdenk		When this option is #defined, the existence of the
541c609719bSwdenk		environment variable "preboot" will be checked
542c609719bSwdenk		immediately before starting the CONFIG_BOOTDELAY
543c609719bSwdenk		countdown and/or running the auto-boot command resp.
544c609719bSwdenk		entering interactive mode.
545c609719bSwdenk
546c609719bSwdenk		This feature is especially useful when "preboot" is
547c609719bSwdenk		automatically generated or modified. For an example
548c609719bSwdenk		see the LWMON board specific code: here "preboot" is
549c609719bSwdenk		modified when the user holds down a certain
550c609719bSwdenk		combination of keys on the (special) keyboard when
551c609719bSwdenk		booting the systems
552c609719bSwdenk
553c609719bSwdenk- Serial Download Echo Mode:
554c609719bSwdenk		CONFIG_LOADS_ECHO
555c609719bSwdenk		If defined to 1, all characters received during a
556c609719bSwdenk		serial download (using the "loads" command) are
557c609719bSwdenk		echoed back. This might be needed by some terminal
558c609719bSwdenk		emulations (like "cu"), but may as well just take
559c609719bSwdenk		time on others. This setting #define's the initial
560c609719bSwdenk		value of the "loads_echo" environment variable.
561c609719bSwdenk
562602ad3b3SJon Loeliger- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
563c609719bSwdenk		CONFIG_KGDB_BAUDRATE
564c609719bSwdenk		Select one of the baudrates listed in
565c609719bSwdenk		CFG_BAUDRATE_TABLE, see below.
566c609719bSwdenk
567c609719bSwdenk- Monitor Functions:
568602ad3b3SJon Loeliger		Monitor commands can be included or excluded
569602ad3b3SJon Loeliger		from the build by using the #include files
570602ad3b3SJon Loeliger		"config_cmd_all.h" and #undef'ing unwanted
571602ad3b3SJon Loeliger		commands, or using "config_cmd_default.h"
572602ad3b3SJon Loeliger		and augmenting with additional #define's
573602ad3b3SJon Loeliger		for wanted commands.
574c609719bSwdenk
575602ad3b3SJon Loeliger		The default command configuration includes all commands
576602ad3b3SJon Loeliger		except those marked below with a "*".
577602ad3b3SJon Loeliger
578602ad3b3SJon Loeliger		CONFIG_CMD_ASKENV	* ask for env variable
579602ad3b3SJon Loeliger		CONFIG_CMD_AUTOSCRIPT	  Autoscript Support
580602ad3b3SJon Loeliger		CONFIG_CMD_BDI		  bdinfo
581602ad3b3SJon Loeliger		CONFIG_CMD_BEDBUG	* Include BedBug Debugger
582602ad3b3SJon Loeliger		CONFIG_CMD_BMP		* BMP support
583602ad3b3SJon Loeliger		CONFIG_CMD_BSP		* Board specific commands
584602ad3b3SJon Loeliger		CONFIG_CMD_BOOTD	  bootd
585602ad3b3SJon Loeliger		CONFIG_CMD_CACHE	* icache, dcache
586602ad3b3SJon Loeliger		CONFIG_CMD_CONSOLE	  coninfo
587602ad3b3SJon Loeliger		CONFIG_CMD_DATE		* support for RTC, date/time...
588602ad3b3SJon Loeliger		CONFIG_CMD_DHCP		* DHCP support
589602ad3b3SJon Loeliger		CONFIG_CMD_DIAG		* Diagnostics
590602ad3b3SJon Loeliger		CONFIG_CMD_DOC		* Disk-On-Chip Support
591602ad3b3SJon Loeliger		CONFIG_CMD_DTT		* Digital Therm and Thermostat
592602ad3b3SJon Loeliger		CONFIG_CMD_ECHO		  echo arguments
593602ad3b3SJon Loeliger		CONFIG_CMD_EEPROM	* EEPROM read/write support
594602ad3b3SJon Loeliger		CONFIG_CMD_ELF		* bootelf, bootvx
595602ad3b3SJon Loeliger		CONFIG_CMD_ENV		  saveenv
596602ad3b3SJon Loeliger		CONFIG_CMD_FDC		* Floppy Disk Support
597602ad3b3SJon Loeliger		CONFIG_CMD_FAT		* FAT partition support
598602ad3b3SJon Loeliger		CONFIG_CMD_FDOS		* Dos diskette Support
599602ad3b3SJon Loeliger		CONFIG_CMD_FLASH	  flinfo, erase, protect
600602ad3b3SJon Loeliger		CONFIG_CMD_FPGA		  FPGA device initialization support
601602ad3b3SJon Loeliger		CONFIG_CMD_HWFLOW	* RTS/CTS hw flow control
602602ad3b3SJon Loeliger		CONFIG_CMD_I2C		* I2C serial bus support
603602ad3b3SJon Loeliger		CONFIG_CMD_IDE		* IDE harddisk support
604602ad3b3SJon Loeliger		CONFIG_CMD_IMI		  iminfo
605602ad3b3SJon Loeliger		CONFIG_CMD_IMLS		  List all found images
606602ad3b3SJon Loeliger		CONFIG_CMD_IMMAP	* IMMR dump support
607602ad3b3SJon Loeliger		CONFIG_CMD_IRQ		* irqinfo
608602ad3b3SJon Loeliger		CONFIG_CMD_ITEST	  Integer/string test of 2 values
609602ad3b3SJon Loeliger		CONFIG_CMD_JFFS2	* JFFS2 Support
610602ad3b3SJon Loeliger		CONFIG_CMD_KGDB		* kgdb
611602ad3b3SJon Loeliger		CONFIG_CMD_LOADB	  loadb
612602ad3b3SJon Loeliger		CONFIG_CMD_LOADS	  loads
613602ad3b3SJon Loeliger		CONFIG_CMD_MEMORY	  md, mm, nm, mw, cp, cmp, crc, base,
61456523f12Swdenk					  loop, loopw, mtest
615602ad3b3SJon Loeliger		CONFIG_CMD_MISC		  Misc functions like sleep etc
616602ad3b3SJon Loeliger		CONFIG_CMD_MMC		* MMC memory mapped support
617602ad3b3SJon Loeliger		CONFIG_CMD_MII		* MII utility commands
618602ad3b3SJon Loeliger		CONFIG_CMD_NAND		* NAND support
619602ad3b3SJon Loeliger		CONFIG_CMD_NET		  bootp, tftpboot, rarpboot
620602ad3b3SJon Loeliger		CONFIG_CMD_PCI		* pciinfo
621602ad3b3SJon Loeliger		CONFIG_CMD_PCMCIA		* PCMCIA support
622602ad3b3SJon Loeliger		CONFIG_CMD_PING		* send ICMP ECHO_REQUEST to network
623602ad3b3SJon Loeliger					  host
624602ad3b3SJon Loeliger		CONFIG_CMD_PORTIO	* Port I/O
625602ad3b3SJon Loeliger		CONFIG_CMD_REGINFO	* Register dump
626602ad3b3SJon Loeliger		CONFIG_CMD_RUN		  run command in env variable
627602ad3b3SJon Loeliger		CONFIG_CMD_SAVES	* save S record dump
628602ad3b3SJon Loeliger		CONFIG_CMD_SCSI		* SCSI Support
629602ad3b3SJon Loeliger		CONFIG_CMD_SDRAM	* print SDRAM configuration information
630602ad3b3SJon Loeliger					  (requires CONFIG_CMD_I2C)
631602ad3b3SJon Loeliger		CONFIG_CMD_SETGETDCR	  Support for DCR Register access
632602ad3b3SJon Loeliger					  (4xx only)
633602ad3b3SJon Loeliger		CONFIG_CMD_SPI		* SPI serial bus support
634602ad3b3SJon Loeliger		CONFIG_CMD_USB		* USB support
635602ad3b3SJon Loeliger		CONFIG_CMD_VFD		* VFD support (TRAB)
636602ad3b3SJon Loeliger		CONFIG_CMD_BSP		* Board SPecific functions
637602ad3b3SJon Loeliger		CONFIG_CMD_CDP		* Cisco Discover Protocol support
638602ad3b3SJon Loeliger		CONFIG_CMD_FSL		* Microblaze FSL support
639c609719bSwdenk
640c609719bSwdenk
641c609719bSwdenk		EXAMPLE: If you want all functions except of network
642c609719bSwdenk		support you can write:
643c609719bSwdenk
644602ad3b3SJon Loeliger		#include "config_cmd_all.h"
645602ad3b3SJon Loeliger		#undef CONFIG_CMD_NET
646c609719bSwdenk
647213bf8c8SGerald Van Baren	Other Commands:
648213bf8c8SGerald Van Baren		fdt (flattened device tree) command: CONFIG_OF_LIBFDT
649c609719bSwdenk
650c609719bSwdenk	Note:	Don't enable the "icache" and "dcache" commands
651602ad3b3SJon Loeliger		(configuration option CONFIG_CMD_CACHE) unless you know
652c609719bSwdenk		what you (and your U-Boot users) are doing. Data
653c609719bSwdenk		cache cannot be enabled on systems like the 8xx or
654c609719bSwdenk		8260 (where accesses to the IMMR region must be
655c609719bSwdenk		uncached), and it cannot be disabled on all other
656c609719bSwdenk		systems where we (mis-) use the data cache to hold an
657c609719bSwdenk		initial stack and some data.
658c609719bSwdenk
659c609719bSwdenk
660c609719bSwdenk		XXX - this list needs to get updated!
661c609719bSwdenk
662c609719bSwdenk- Watchdog:
663c609719bSwdenk		CONFIG_WATCHDOG
664c609719bSwdenk		If this variable is defined, it enables watchdog
6657152b1d0Swdenk		support. There must be support in the platform specific
666c609719bSwdenk		code for a watchdog. For the 8xx and 8260 CPUs, the
667c609719bSwdenk		SIU Watchdog feature is enabled in the SYPCR
668c609719bSwdenk		register.
669c609719bSwdenk
670c1551ea8Sstroese- U-Boot Version:
671c1551ea8Sstroese		CONFIG_VERSION_VARIABLE
672c1551ea8Sstroese		If this variable is defined, an environment variable
673c1551ea8Sstroese		named "ver" is created by U-Boot showing the U-Boot
674c1551ea8Sstroese		version as printed by the "version" command.
675c1551ea8Sstroese		This variable is readonly.
676c1551ea8Sstroese
677c609719bSwdenk- Real-Time Clock:
678c609719bSwdenk
679602ad3b3SJon Loeliger		When CONFIG_CMD_DATE is selected, the type of the RTC
680c609719bSwdenk		has to be selected, too. Define exactly one of the
681c609719bSwdenk		following options:
682c609719bSwdenk
683c609719bSwdenk		CONFIG_RTC_MPC8xx	- use internal RTC of MPC8xx
684c609719bSwdenk		CONFIG_RTC_PCF8563	- use Philips PCF8563 RTC
685c609719bSwdenk		CONFIG_RTC_MC146818	- use MC146818 RTC
6861cb8e980Swdenk		CONFIG_RTC_DS1307	- use Maxim, Inc. DS1307 RTC
687c609719bSwdenk		CONFIG_RTC_DS1337	- use Maxim, Inc. DS1337 RTC
6887f70e853Swdenk		CONFIG_RTC_DS1338	- use Maxim, Inc. DS1338 RTC
6893bac3513Swdenk		CONFIG_RTC_DS164x	- use Dallas DS164x RTC
6909536dfccSTor Krill		CONFIG_RTC_ISL1208	- use Intersil ISL1208 RTC
6914c0d4c3bSwdenk		CONFIG_RTC_MAX6900	- use Maxim, Inc. MAX6900 RTC
692da8808dfSJoakim Tjernlund		CFG_RTC_DS1337_NOOSC	- Turn off the OSC output for DS1337
693c609719bSwdenk
694b37c7e5eSwdenk		Note that if the RTC uses I2C, then the I2C interface
695b37c7e5eSwdenk		must also be configured. See I2C Support, below.
696b37c7e5eSwdenk
697c609719bSwdenk- Timestamp Support:
698c609719bSwdenk
699c609719bSwdenk		When CONFIG_TIMESTAMP is selected, the timestamp
700c609719bSwdenk		(date and time) of an image is printed by image
701c609719bSwdenk		commands like bootm or iminfo. This option is
702602ad3b3SJon Loeliger		automatically enabled when you select CONFIG_CMD_DATE .
703c609719bSwdenk
704c609719bSwdenk- Partition Support:
705c609719bSwdenk		CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
706c609719bSwdenk		and/or CONFIG_ISO_PARTITION
707c609719bSwdenk
708602ad3b3SJon Loeliger		If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
709218ca724SWolfgang Denk		CONFIG_CMD_SCSI) you must configure support for at
710218ca724SWolfgang Denk		least one partition type as well.
711c609719bSwdenk
712c609719bSwdenk- IDE Reset method:
7134d13cbadSwdenk		CONFIG_IDE_RESET_ROUTINE - this is defined in several
7144d13cbadSwdenk		board configurations files but used nowhere!
715c609719bSwdenk
7164d13cbadSwdenk		CONFIG_IDE_RESET - is this is defined, IDE Reset will
7174d13cbadSwdenk		be performed by calling the function
7184d13cbadSwdenk			ide_set_reset(int reset)
7194d13cbadSwdenk		which has to be defined in a board specific file
720c609719bSwdenk
721c609719bSwdenk- ATAPI Support:
722c609719bSwdenk		CONFIG_ATAPI
723c609719bSwdenk
724c609719bSwdenk		Set this to enable ATAPI support.
725c609719bSwdenk
726c40b2956Swdenk- LBA48 Support
727c40b2956Swdenk		CONFIG_LBA48
728c40b2956Swdenk
729c40b2956Swdenk		Set this to enable support for disks larger than 137GB
730c40b2956Swdenk		Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
731c40b2956Swdenk		Whithout these , LBA48 support uses 32bit variables and will 'only'
732c40b2956Swdenk		support disks up to 2.1TB.
733c40b2956Swdenk
734c40b2956Swdenk		CFG_64BIT_LBA:
735c40b2956Swdenk			When enabled, makes the IDE subsystem use 64bit sector addresses.
736c40b2956Swdenk			Default is 32bit.
737c40b2956Swdenk
738c609719bSwdenk- SCSI Support:
739c609719bSwdenk		At the moment only there is only support for the
740c609719bSwdenk		SYM53C8XX SCSI controller; define
741c609719bSwdenk		CONFIG_SCSI_SYM53C8XX to enable it.
742c609719bSwdenk
743c609719bSwdenk		CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
744c609719bSwdenk		CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
745c609719bSwdenk		CFG_SCSI_MAX_LUN] can be adjusted to define the
746c609719bSwdenk		maximum numbers of LUNs, SCSI ID's and target
747c609719bSwdenk		devices.
748c609719bSwdenk		CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
749c609719bSwdenk
750c609719bSwdenk- NETWORK Support (PCI):
751682011ffSwdenk		CONFIG_E1000
752682011ffSwdenk		Support for Intel 8254x gigabit chips.
753682011ffSwdenk
754c609719bSwdenk		CONFIG_EEPRO100
755c609719bSwdenk		Support for Intel 82557/82559/82559ER chips.
756c609719bSwdenk		Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
757c609719bSwdenk		write routine for first time initialisation.
758c609719bSwdenk
759c609719bSwdenk		CONFIG_TULIP
760c609719bSwdenk		Support for Digital 2114x chips.
761c609719bSwdenk		Optional CONFIG_TULIP_SELECT_MEDIA for board specific
762c609719bSwdenk		modem chip initialisation (KS8761/QS6611).
763c609719bSwdenk
764c609719bSwdenk		CONFIG_NATSEMI
765c609719bSwdenk		Support for National dp83815 chips.
766c609719bSwdenk
767c609719bSwdenk		CONFIG_NS8382X
768c609719bSwdenk		Support for National dp8382[01] gigabit chips.
769c609719bSwdenk
77045219c46Swdenk- NETWORK Support (other):
77145219c46Swdenk
77245219c46Swdenk		CONFIG_DRIVER_LAN91C96
77345219c46Swdenk		Support for SMSC's LAN91C96 chips.
77445219c46Swdenk
77545219c46Swdenk			CONFIG_LAN91C96_BASE
77645219c46Swdenk			Define this to hold the physical address
77745219c46Swdenk			of the LAN91C96's I/O space
77845219c46Swdenk
77945219c46Swdenk			CONFIG_LAN91C96_USE_32_BIT
78045219c46Swdenk			Define this to enable 32 bit addressing
78145219c46Swdenk
782f39748aeSwdenk		CONFIG_DRIVER_SMC91111
783f39748aeSwdenk		Support for SMSC's LAN91C111 chip
784f39748aeSwdenk
785f39748aeSwdenk			CONFIG_SMC91111_BASE
786f39748aeSwdenk			Define this to hold the physical address
787f39748aeSwdenk			of the device (I/O space)
788f39748aeSwdenk
789f39748aeSwdenk			CONFIG_SMC_USE_32_BIT
790f39748aeSwdenk			Define this if data bus is 32 bits
791f39748aeSwdenk
792f39748aeSwdenk			CONFIG_SMC_USE_IOFUNCS
793f39748aeSwdenk			Define this to use i/o functions instead of macros
794f39748aeSwdenk			(some hardware wont work with macros)
795f39748aeSwdenk
796c609719bSwdenk- USB Support:
797c609719bSwdenk		At the moment only the UHCI host controller is
7984d13cbadSwdenk		supported (PIP405, MIP405, MPC5200); define
799c609719bSwdenk		CONFIG_USB_UHCI to enable it.
800c609719bSwdenk		define CONFIG_USB_KEYBOARD to enable the USB Keyboard
80130d56faeSwdenk		and define CONFIG_USB_STORAGE to enable the USB
802c609719bSwdenk		storage devices.
803c609719bSwdenk		Note:
804c609719bSwdenk		Supported are USB Keyboards and USB Floppy drives
805c609719bSwdenk		(TEAC FD-05PUB).
8064d13cbadSwdenk		MPC5200 USB requires additional defines:
8074d13cbadSwdenk			CONFIG_USB_CLOCK
8084d13cbadSwdenk				for 528 MHz Clock: 0x0001bbbb
8094d13cbadSwdenk			CONFIG_USB_CONFIG
8104d13cbadSwdenk				for differential drivers: 0x00001000
8114d13cbadSwdenk				for single ended drivers: 0x00005000
812fdcfaa1bSZhang Wei			CFG_USB_EVENT_POLL
813fdcfaa1bSZhang Wei				May be defined to allow interrupt polling
814fdcfaa1bSZhang Wei				instead of using asynchronous interrupts
8154d13cbadSwdenk
81616c8d5e7SWolfgang Denk- USB Device:
81716c8d5e7SWolfgang Denk		Define the below if you wish to use the USB console.
81816c8d5e7SWolfgang Denk		Once firmware is rebuilt from a serial console issue the
81916c8d5e7SWolfgang Denk		command "setenv stdin usbtty; setenv stdout usbtty" and
82016c8d5e7SWolfgang Denk		attach your usb cable. The Unix command "dmesg" should print
82116c8d5e7SWolfgang Denk		it has found a new device. The environment variable usbtty
82216c8d5e7SWolfgang Denk		can be set to gserial or cdc_acm to enable your device to
82316c8d5e7SWolfgang Denk		appear to a USB host as a Linux gserial device or a
82416c8d5e7SWolfgang Denk		Common Device Class Abstract Control Model serial device.
82516c8d5e7SWolfgang Denk		If you select usbtty = gserial you should be able to enumerate
82616c8d5e7SWolfgang Denk		a Linux host by
82716c8d5e7SWolfgang Denk		# modprobe usbserial vendor=0xVendorID product=0xProductID
82816c8d5e7SWolfgang Denk		else if using cdc_acm, simply setting the environment
82916c8d5e7SWolfgang Denk		variable usbtty to be cdc_acm should suffice. The following
83016c8d5e7SWolfgang Denk		might be defined in YourBoardName.h
83116c8d5e7SWolfgang Denk
83216c8d5e7SWolfgang Denk			CONFIG_USB_DEVICE
83316c8d5e7SWolfgang Denk			Define this to build a UDC device
83416c8d5e7SWolfgang Denk
83516c8d5e7SWolfgang Denk			CONFIG_USB_TTY
83616c8d5e7SWolfgang Denk			Define this to have a tty type of device available to
83716c8d5e7SWolfgang Denk			talk to the UDC device
83816c8d5e7SWolfgang Denk
83916c8d5e7SWolfgang Denk			CFG_CONSOLE_IS_IN_ENV
84016c8d5e7SWolfgang Denk			Define this if you want stdin, stdout &/or stderr to
84116c8d5e7SWolfgang Denk			be set to usbtty.
84216c8d5e7SWolfgang Denk
84316c8d5e7SWolfgang Denk			mpc8xx:
84416c8d5e7SWolfgang Denk				CFG_USB_EXTC_CLK 0xBLAH
84516c8d5e7SWolfgang Denk				Derive USB clock from external clock "blah"
84616c8d5e7SWolfgang Denk				- CFG_USB_EXTC_CLK 0x02
84716c8d5e7SWolfgang Denk
84816c8d5e7SWolfgang Denk				CFG_USB_BRG_CLK 0xBLAH
84916c8d5e7SWolfgang Denk				Derive USB clock from brgclk
85016c8d5e7SWolfgang Denk				- CFG_USB_BRG_CLK 0x04
85116c8d5e7SWolfgang Denk
85216c8d5e7SWolfgang Denk		If you have a USB-IF assigned VendorID then you may wish to
85316c8d5e7SWolfgang Denk		define your own vendor specific values either in BoardName.h
85416c8d5e7SWolfgang Denk		or directly in usbd_vendor_info.h. If you don't define
85516c8d5e7SWolfgang Denk		CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
85616c8d5e7SWolfgang Denk		CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
85716c8d5e7SWolfgang Denk		should pretend to be a Linux device to it's target host.
85816c8d5e7SWolfgang Denk
85916c8d5e7SWolfgang Denk			CONFIG_USBD_MANUFACTURER
86016c8d5e7SWolfgang Denk			Define this string as the name of your company for
86116c8d5e7SWolfgang Denk			- CONFIG_USBD_MANUFACTURER "my company"
86216c8d5e7SWolfgang Denk
86316c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCT_NAME
86416c8d5e7SWolfgang Denk			Define this string as the name of your product
86516c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCT_NAME "acme usb device"
86616c8d5e7SWolfgang Denk
86716c8d5e7SWolfgang Denk			CONFIG_USBD_VENDORID
86816c8d5e7SWolfgang Denk			Define this as your assigned Vendor ID from the USB
86916c8d5e7SWolfgang Denk			Implementors Forum. This *must* be a genuine Vendor ID
87016c8d5e7SWolfgang Denk			to avoid polluting the USB namespace.
87116c8d5e7SWolfgang Denk			- CONFIG_USBD_VENDORID 0xFFFF
87216c8d5e7SWolfgang Denk
87316c8d5e7SWolfgang Denk			CONFIG_USBD_PRODUCTID
87416c8d5e7SWolfgang Denk			Define this as the unique Product ID
87516c8d5e7SWolfgang Denk			for your device
87616c8d5e7SWolfgang Denk			- CONFIG_USBD_PRODUCTID 0xFFFF
877c609719bSwdenk
878c609719bSwdenk
879c609719bSwdenk- MMC Support:
880c609719bSwdenk		The MMC controller on the Intel PXA is supported. To
881c609719bSwdenk		enable this define CONFIG_MMC. The MMC can be
882c609719bSwdenk		accessed from the boot prompt by mapping the device
883c609719bSwdenk		to physical memory similar to flash. Command line is
884602ad3b3SJon Loeliger		enabled with CONFIG_CMD_MMC. The MMC driver also works with
885602ad3b3SJon Loeliger		the FAT fs. This is enabled with CONFIG_CMD_FAT.
886c609719bSwdenk
8876705d81eSwdenk- Journaling Flash filesystem support:
8886705d81eSwdenk		CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
8896705d81eSwdenk		CONFIG_JFFS2_NAND_DEV
8906705d81eSwdenk		Define these for a default partition on a NAND device
8916705d81eSwdenk
8926705d81eSwdenk		CFG_JFFS2_FIRST_SECTOR,
8936705d81eSwdenk		CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
8946705d81eSwdenk		Define these for a default partition on a NOR device
8956705d81eSwdenk
8966705d81eSwdenk		CFG_JFFS_CUSTOM_PART
8976705d81eSwdenk		Define this to create an own partition. You have to provide a
8986705d81eSwdenk		function struct part_info* jffs2_part_info(int part_num)
8996705d81eSwdenk
9006705d81eSwdenk		If you define only one JFFS2 partition you may also want to
9016705d81eSwdenk		#define CFG_JFFS_SINGLE_PART	1
9026705d81eSwdenk		to disable the command chpart. This is the default when you
9036705d81eSwdenk		have not defined a custom partition
9046705d81eSwdenk
905c609719bSwdenk- Keyboard Support:
906c609719bSwdenk		CONFIG_ISA_KEYBOARD
907c609719bSwdenk
908c609719bSwdenk		Define this to enable standard (PC-Style) keyboard
909c609719bSwdenk		support
910c609719bSwdenk
911c609719bSwdenk		CONFIG_I8042_KBD
912c609719bSwdenk		Standard PC keyboard driver with US (is default) and
913c609719bSwdenk		GERMAN key layout (switch via environment 'keymap=de') support.
914c609719bSwdenk		Export function i8042_kbd_init, i8042_tstc and i8042_getc
915c609719bSwdenk		for cfb_console. Supports cursor blinking.
916c609719bSwdenk
917c609719bSwdenk- Video support:
918c609719bSwdenk		CONFIG_VIDEO
919c609719bSwdenk
920c609719bSwdenk		Define this to enable video support (for output to
921c609719bSwdenk		video).
922c609719bSwdenk
923c609719bSwdenk		CONFIG_VIDEO_CT69000
924c609719bSwdenk
925c609719bSwdenk		Enable Chips & Technologies 69000 Video chip
926c609719bSwdenk
927c609719bSwdenk		CONFIG_VIDEO_SMI_LYNXEM
928eeb1b77bSwdenk		Enable Silicon Motion SMI 712/710/810 Video chip. The
929eeb1b77bSwdenk		video output is selected via environment 'videoout'
930eeb1b77bSwdenk		(1 = LCD and 2 = CRT). If videoout is undefined, CRT is
931eeb1b77bSwdenk		assumed.
932c609719bSwdenk
933eeb1b77bSwdenk		For the CT69000 and SMI_LYNXEM drivers, videomode is
934eeb1b77bSwdenk		selected via environment 'videomode'. Two diferent ways
935eeb1b77bSwdenk		are possible:
936eeb1b77bSwdenk		- "videomode=num"   'num' is a standard LiLo mode numbers.
937eeb1b77bSwdenk		Following standard modes are supported	(* is default):
938eeb1b77bSwdenk
939eeb1b77bSwdenk		      Colors	640x480 800x600 1024x768 1152x864 1280x1024
940eeb1b77bSwdenk		-------------+---------------------------------------------
941eeb1b77bSwdenk		      8 bits |	0x301*	0x303	 0x305	  0x161	    0x307
942eeb1b77bSwdenk		     15 bits |	0x310	0x313	 0x316	  0x162	    0x319
943eeb1b77bSwdenk		     16 bits |	0x311	0x314	 0x317	  0x163	    0x31A
944eeb1b77bSwdenk		     24 bits |	0x312	0x315	 0x318	    ?	    0x31B
945eeb1b77bSwdenk		-------------+---------------------------------------------
946c609719bSwdenk		(i.e. setenv videomode 317; saveenv; reset;)
947c609719bSwdenk
948eeb1b77bSwdenk		- "videomode=bootargs" all the video parameters are parsed
9497817cb20SMarcel Ziswiler		from the bootargs. (See drivers/video/videomodes.c)
950eeb1b77bSwdenk
951eeb1b77bSwdenk
952a6c7ad2fSwdenk		CONFIG_VIDEO_SED13806
953a6c7ad2fSwdenk		Enable Epson SED13806 driver. This driver supports 8bpp
954a6c7ad2fSwdenk		and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
955a6c7ad2fSwdenk		or CONFIG_VIDEO_SED13806_16BPP
956a6c7ad2fSwdenk
957682011ffSwdenk- Keyboard Support:
958682011ffSwdenk		CONFIG_KEYBOARD
959682011ffSwdenk
960682011ffSwdenk		Define this to enable a custom keyboard support.
961682011ffSwdenk		This simply calls drv_keyboard_init() which must be
962682011ffSwdenk		defined in your board-specific files.
963682011ffSwdenk		The only board using this so far is RBC823.
964a6c7ad2fSwdenk
965c609719bSwdenk- LCD Support:	CONFIG_LCD
966c609719bSwdenk
967c609719bSwdenk		Define this to enable LCD support (for output to LCD
968c609719bSwdenk		display); also select one of the supported displays
969c609719bSwdenk		by defining one of these:
970c609719bSwdenk
971fd3103bbSwdenk		CONFIG_NEC_NL6448AC33:
972c609719bSwdenk
973fd3103bbSwdenk			NEC NL6448AC33-18. Active, color, single scan.
974c609719bSwdenk
975fd3103bbSwdenk		CONFIG_NEC_NL6448BC20
976c609719bSwdenk
977fd3103bbSwdenk			NEC NL6448BC20-08. 6.5", 640x480.
978fd3103bbSwdenk			Active, color, single scan.
979fd3103bbSwdenk
980fd3103bbSwdenk		CONFIG_NEC_NL6448BC33_54
981fd3103bbSwdenk
982fd3103bbSwdenk			NEC NL6448BC33-54. 10.4", 640x480.
983c609719bSwdenk			Active, color, single scan.
984c609719bSwdenk
985c609719bSwdenk		CONFIG_SHARP_16x9
986c609719bSwdenk
987c609719bSwdenk			Sharp 320x240. Active, color, single scan.
988c609719bSwdenk			It isn't 16x9, and I am not sure what it is.
989c609719bSwdenk
990c609719bSwdenk		CONFIG_SHARP_LQ64D341
991c609719bSwdenk
992c609719bSwdenk			Sharp LQ64D341 display, 640x480.
993c609719bSwdenk			Active, color, single scan.
994c609719bSwdenk
995c609719bSwdenk		CONFIG_HLD1045
996c609719bSwdenk
997c609719bSwdenk			HLD1045 display, 640x480.
998c609719bSwdenk			Active, color, single scan.
999c609719bSwdenk
1000c609719bSwdenk		CONFIG_OPTREX_BW
1001c609719bSwdenk
1002c609719bSwdenk			Optrex	 CBL50840-2 NF-FW 99 22 M5
1003c609719bSwdenk			or
1004c609719bSwdenk			Hitachi	 LMG6912RPFC-00T
1005c609719bSwdenk			or
1006c609719bSwdenk			Hitachi	 SP14Q002
1007c609719bSwdenk
1008c609719bSwdenk			320x240. Black & white.
1009c609719bSwdenk
1010c609719bSwdenk		Normally display is black on white background; define
1011c609719bSwdenk		CFG_WHITE_ON_BLACK to get it inverted.
1012c609719bSwdenk
10137152b1d0Swdenk- Splash Screen Support: CONFIG_SPLASH_SCREEN
1014d791b1dcSwdenk
1015d791b1dcSwdenk		If this option is set, the environment is checked for
1016d791b1dcSwdenk		a variable "splashimage". If found, the usual display
1017d791b1dcSwdenk		of logo, copyright and system information on the LCD
1018e94d2cd9Swdenk		is suppressed and the BMP image at the address
1019d791b1dcSwdenk		specified in "splashimage" is loaded instead. The
1020d791b1dcSwdenk		console is redirected to the "nulldev", too. This
1021d791b1dcSwdenk		allows for a "silent" boot where a splash screen is
1022d791b1dcSwdenk		loaded very quickly after power-on.
1023d791b1dcSwdenk
102498f4a3dfSStefan Roese- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
102598f4a3dfSStefan Roese
102698f4a3dfSStefan Roese		If this option is set, additionally to standard BMP
102798f4a3dfSStefan Roese		images, gzipped BMP images can be displayed via the
102898f4a3dfSStefan Roese		splashscreen support or the bmp command.
102998f4a3dfSStefan Roese
1030c29fdfc1Swdenk- Compression support:
1031c29fdfc1Swdenk		CONFIG_BZIP2
1032c29fdfc1Swdenk
1033c29fdfc1Swdenk		If this option is set, support for bzip2 compressed
1034c29fdfc1Swdenk		images is included. If not, only uncompressed and gzip
1035c29fdfc1Swdenk		compressed images are supported.
1036c29fdfc1Swdenk
1037c29fdfc1Swdenk		NOTE: the bzip2 algorithm requires a lot of RAM, so
1038c29fdfc1Swdenk		the malloc area (as defined by CFG_MALLOC_LEN) should
1039c29fdfc1Swdenk		be at least 4MB.
1040d791b1dcSwdenk
104117ea1177Swdenk- MII/PHY support:
104217ea1177Swdenk		CONFIG_PHY_ADDR
104317ea1177Swdenk
104417ea1177Swdenk		The address of PHY on MII bus.
104517ea1177Swdenk
104617ea1177Swdenk		CONFIG_PHY_CLOCK_FREQ (ppc4xx)
104717ea1177Swdenk
104817ea1177Swdenk		The clock frequency of the MII bus
104917ea1177Swdenk
105017ea1177Swdenk		CONFIG_PHY_GIGE
105117ea1177Swdenk
105217ea1177Swdenk		If this option is set, support for speed/duplex
105317ea1177Swdenk		detection of Gigabit PHY is included.
105417ea1177Swdenk
105517ea1177Swdenk		CONFIG_PHY_RESET_DELAY
105617ea1177Swdenk
105717ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
105817ea1177Swdenk		reset before any MII register access is possible.
105917ea1177Swdenk		For such PHY, set this option to the usec delay
106017ea1177Swdenk		required. (minimum 300usec for LXT971A)
106117ea1177Swdenk
106217ea1177Swdenk		CONFIG_PHY_CMD_DELAY (ppc4xx)
106317ea1177Swdenk
106417ea1177Swdenk		Some PHY like Intel LXT971A need extra delay after
106517ea1177Swdenk		command issued before MII status register can be read
106617ea1177Swdenk
1067c609719bSwdenk- Ethernet address:
1068c609719bSwdenk		CONFIG_ETHADDR
1069c609719bSwdenk		CONFIG_ETH2ADDR
1070c609719bSwdenk		CONFIG_ETH3ADDR
1071c609719bSwdenk
1072c609719bSwdenk		Define a default value for ethernet address to use
1073c609719bSwdenk		for the respective ethernet interface, in case this
1074c609719bSwdenk		is not determined automatically.
1075c609719bSwdenk
1076c609719bSwdenk- IP address:
1077c609719bSwdenk		CONFIG_IPADDR
1078c609719bSwdenk
1079c609719bSwdenk		Define a default value for the IP address to use for
1080c609719bSwdenk		the default ethernet interface, in case this is not
1081c609719bSwdenk		determined through e.g. bootp.
1082c609719bSwdenk
1083c609719bSwdenk- Server IP address:
1084c609719bSwdenk		CONFIG_SERVERIP
1085c609719bSwdenk
1086c609719bSwdenk		Defines a default value for theIP address of a TFTP
1087c609719bSwdenk		server to contact when using the "tftboot" command.
1088c609719bSwdenk
108953a5c424SDavid Updegraff- Multicast TFTP Mode:
109053a5c424SDavid Updegraff		CONFIG_MCAST_TFTP
109153a5c424SDavid Updegraff
109253a5c424SDavid Updegraff		Defines whether you want to support multicast TFTP as per
109353a5c424SDavid Updegraff		rfc-2090; for example to work with atftp.  Lets lots of targets
109453a5c424SDavid Updegraff		tftp down the same boot image concurrently.  Note: the ethernet
109553a5c424SDavid Updegraff		driver in use must provide a function: mcast() to join/leave a
109653a5c424SDavid Updegraff		multicast group.
109753a5c424SDavid Updegraff
109853a5c424SDavid Updegraff		CONFIG_BOOTP_RANDOM_DELAY
1099c609719bSwdenk- BOOTP Recovery Mode:
1100c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY
1101c609719bSwdenk
1102c609719bSwdenk		If you have many targets in a network that try to
1103c609719bSwdenk		boot using BOOTP, you may want to avoid that all
1104c609719bSwdenk		systems send out BOOTP requests at precisely the same
1105c609719bSwdenk		moment (which would happen for instance at recovery
1106c609719bSwdenk		from a power failure, when all systems will try to
1107c609719bSwdenk		boot, thus flooding the BOOTP server. Defining
1108c609719bSwdenk		CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1109c609719bSwdenk		inserted before sending out BOOTP requests. The
11106c33c785SWolfgang Denk		following delays are inserted then:
1111c609719bSwdenk
1112c609719bSwdenk		1st BOOTP request:	delay 0 ... 1 sec
1113c609719bSwdenk		2nd BOOTP request:	delay 0 ... 2 sec
1114c609719bSwdenk		3rd BOOTP request:	delay 0 ... 4 sec
1115c609719bSwdenk		4th and following
1116c609719bSwdenk		BOOTP requests:		delay 0 ... 8 sec
1117c609719bSwdenk
1118fe389a82Sstroese- DHCP Advanced Options:
11191fe80d79SJon Loeliger		You can fine tune the DHCP functionality by defining
11201fe80d79SJon Loeliger		CONFIG_BOOTP_* symbols:
1121fe389a82Sstroese
11221fe80d79SJon Loeliger		CONFIG_BOOTP_SUBNETMASK
11231fe80d79SJon Loeliger		CONFIG_BOOTP_GATEWAY
11241fe80d79SJon Loeliger		CONFIG_BOOTP_HOSTNAME
11251fe80d79SJon Loeliger		CONFIG_BOOTP_NISDOMAIN
11261fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTPATH
11271fe80d79SJon Loeliger		CONFIG_BOOTP_BOOTFILESIZE
11281fe80d79SJon Loeliger		CONFIG_BOOTP_DNS
11291fe80d79SJon Loeliger		CONFIG_BOOTP_DNS2
11301fe80d79SJon Loeliger		CONFIG_BOOTP_SEND_HOSTNAME
11311fe80d79SJon Loeliger		CONFIG_BOOTP_NTPSERVER
11321fe80d79SJon Loeliger		CONFIG_BOOTP_TIMEOFFSET
11331fe80d79SJon Loeliger		CONFIG_BOOTP_VENDOREX
1134fe389a82Sstroese
11355d110f0aSWilson Callan		CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
11365d110f0aSWilson Callan		environment variable, not the BOOTP server.
1137fe389a82Sstroese
1138fe389a82Sstroese		CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1139fe389a82Sstroese		serverip from a DHCP server, it is possible that more
1140fe389a82Sstroese		than one DNS serverip is offered to the client.
1141fe389a82Sstroese		If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1142fe389a82Sstroese		serverip will be stored in the additional environment
1143fe389a82Sstroese		variable "dnsip2". The first DNS serverip is always
1144fe389a82Sstroese		stored in the variable "dnsip", when CONFIG_BOOTP_DNS
11451fe80d79SJon Loeliger		is defined.
1146fe389a82Sstroese
1147fe389a82Sstroese		CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1148fe389a82Sstroese		to do a dynamic update of a DNS server. To do this, they
1149fe389a82Sstroese		need the hostname of the DHCP requester.
11505d110f0aSWilson Callan		If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
11511fe80d79SJon Loeliger		of the "hostname" environment variable is passed as
11521fe80d79SJon Loeliger		option 12 to the DHCP server.
1153fe389a82Sstroese
1154a3d991bdSwdenk - CDP Options:
1155a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID
1156a3d991bdSwdenk
1157a3d991bdSwdenk		The device id used in CDP trigger frames.
1158a3d991bdSwdenk
1159a3d991bdSwdenk		CONFIG_CDP_DEVICE_ID_PREFIX
1160a3d991bdSwdenk
1161a3d991bdSwdenk		A two character string which is prefixed to the MAC address
1162a3d991bdSwdenk		of the device.
1163a3d991bdSwdenk
1164a3d991bdSwdenk		CONFIG_CDP_PORT_ID
1165a3d991bdSwdenk
1166a3d991bdSwdenk		A printf format string which contains the ascii name of
1167a3d991bdSwdenk		the port. Normally is set to "eth%d" which sets
1168a3d991bdSwdenk		eth0 for the first ethernet, eth1 for the second etc.
1169a3d991bdSwdenk
1170a3d991bdSwdenk		CONFIG_CDP_CAPABILITIES
1171a3d991bdSwdenk
1172a3d991bdSwdenk		A 32bit integer which indicates the device capabilities;
1173a3d991bdSwdenk		0x00000010 for a normal host which does not forwards.
1174a3d991bdSwdenk
1175a3d991bdSwdenk		CONFIG_CDP_VERSION
1176a3d991bdSwdenk
1177a3d991bdSwdenk		An ascii string containing the version of the software.
1178a3d991bdSwdenk
1179a3d991bdSwdenk		CONFIG_CDP_PLATFORM
1180a3d991bdSwdenk
1181a3d991bdSwdenk		An ascii string containing the name of the platform.
1182a3d991bdSwdenk
1183a3d991bdSwdenk		CONFIG_CDP_TRIGGER
1184a3d991bdSwdenk
1185a3d991bdSwdenk		A 32bit integer sent on the trigger.
1186a3d991bdSwdenk
1187a3d991bdSwdenk		CONFIG_CDP_POWER_CONSUMPTION
1188a3d991bdSwdenk
1189a3d991bdSwdenk		A 16bit integer containing the power consumption of the
1190a3d991bdSwdenk		device in .1 of milliwatts.
1191a3d991bdSwdenk
1192a3d991bdSwdenk		CONFIG_CDP_APPLIANCE_VLAN_TYPE
1193a3d991bdSwdenk
1194a3d991bdSwdenk		A byte containing the id of the VLAN.
1195a3d991bdSwdenk
1196c609719bSwdenk- Status LED:	CONFIG_STATUS_LED
1197c609719bSwdenk
1198c609719bSwdenk		Several configurations allow to display the current
1199c609719bSwdenk		status using a LED. For instance, the LED will blink
1200c609719bSwdenk		fast while running U-Boot code, stop blinking as
1201c609719bSwdenk		soon as a reply to a BOOTP request was received, and
1202c609719bSwdenk		start blinking slow once the Linux kernel is running
1203c609719bSwdenk		(supported by a status LED driver in the Linux
1204c609719bSwdenk		kernel). Defining CONFIG_STATUS_LED enables this
1205c609719bSwdenk		feature in U-Boot.
1206c609719bSwdenk
1207c609719bSwdenk- CAN Support:	CONFIG_CAN_DRIVER
1208c609719bSwdenk
1209c609719bSwdenk		Defining CONFIG_CAN_DRIVER enables CAN driver support
1210c609719bSwdenk		on those systems that support this (optional)
1211c609719bSwdenk		feature, like the TQM8xxL modules.
1212c609719bSwdenk
1213c609719bSwdenk- I2C Support:	CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1214c609719bSwdenk
1215b37c7e5eSwdenk		These enable I2C serial bus commands. Defining either of
1216b37c7e5eSwdenk		(but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1217b37c7e5eSwdenk		include the appropriate I2C driver for the selected cpu.
1218c609719bSwdenk
1219b37c7e5eSwdenk		This will allow you to use i2c commands at the u-boot
1220602ad3b3SJon Loeliger		command line (as long as you set CONFIG_CMD_I2C in
1221b37c7e5eSwdenk		CONFIG_COMMANDS) and communicate with i2c based realtime
1222b37c7e5eSwdenk		clock chips. See common/cmd_i2c.c for a description of the
1223c609719bSwdenk		command line interface.
1224c609719bSwdenk
1225bb99ad6dSBen Warren		CONFIG_I2C_CMD_TREE is a recommended option that places
1226bb99ad6dSBen Warren		all I2C commands under a single 'i2c' root command.  The
1227bb99ad6dSBen Warren		older 'imm', 'imd', 'iprobe' etc. commands are considered
1228bb99ad6dSBen Warren		deprecated and may disappear in the future.
1229bb99ad6dSBen Warren
1230bb99ad6dSBen Warren		CONFIG_HARD_I2C selects a hardware I2C controller.
1231c609719bSwdenk
1232b37c7e5eSwdenk		CONFIG_SOFT_I2C configures u-boot to use a software (aka
1233b37c7e5eSwdenk		bit-banging) driver instead of CPM or similar hardware
1234b37c7e5eSwdenk		support for I2C.
1235c609719bSwdenk
1236b37c7e5eSwdenk		There are several other quantities that must also be
1237b37c7e5eSwdenk		defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1238c609719bSwdenk
1239b37c7e5eSwdenk		In both cases you will need to define CFG_I2C_SPEED
1240b37c7e5eSwdenk		to be the frequency (in Hz) at which you wish your i2c bus
1241b37c7e5eSwdenk		to run and CFG_I2C_SLAVE to be the address of this node (ie
1242b37c7e5eSwdenk		the cpu's i2c node address).
1243c609719bSwdenk
1244b37c7e5eSwdenk		Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1245b37c7e5eSwdenk		sets the cpu up as a master node and so its address should
1246b37c7e5eSwdenk		therefore be cleared to 0 (See, eg, MPC823e User's Manual
1247b37c7e5eSwdenk		p.16-473). So, set CFG_I2C_SLAVE to 0.
1248b37c7e5eSwdenk
1249b37c7e5eSwdenk		That's all that's required for CONFIG_HARD_I2C.
1250b37c7e5eSwdenk
1251b37c7e5eSwdenk		If you use the software i2c interface (CONFIG_SOFT_I2C)
1252b37c7e5eSwdenk		then the following macros need to be defined (examples are
1253b37c7e5eSwdenk		from include/configs/lwmon.h):
1254c609719bSwdenk
1255c609719bSwdenk		I2C_INIT
1256c609719bSwdenk
1257b37c7e5eSwdenk		(Optional). Any commands necessary to enable the I2C
1258c609719bSwdenk		controller or configure ports.
1259c609719bSwdenk
1260b37c7e5eSwdenk		eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |=	PB_SCL)
1261b37c7e5eSwdenk
1262c609719bSwdenk		I2C_PORT
1263c609719bSwdenk
1264c609719bSwdenk		(Only for MPC8260 CPU). The I/O port to use (the code
1265c609719bSwdenk		assumes both bits are on the same port). Valid values
1266c609719bSwdenk		are 0..3 for ports A..D.
1267c609719bSwdenk
1268c609719bSwdenk		I2C_ACTIVE
1269c609719bSwdenk
1270c609719bSwdenk		The code necessary to make the I2C data line active
1271c609719bSwdenk		(driven).  If the data line is open collector, this
1272c609719bSwdenk		define can be null.
1273c609719bSwdenk
1274b37c7e5eSwdenk		eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |=  PB_SDA)
1275b37c7e5eSwdenk
1276c609719bSwdenk		I2C_TRISTATE
1277c609719bSwdenk
1278c609719bSwdenk		The code necessary to make the I2C data line tri-stated
1279c609719bSwdenk		(inactive).  If the data line is open collector, this
1280c609719bSwdenk		define can be null.
1281c609719bSwdenk
1282b37c7e5eSwdenk		eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1283b37c7e5eSwdenk
1284c609719bSwdenk		I2C_READ
1285c609719bSwdenk
1286c609719bSwdenk		Code that returns TRUE if the I2C data line is high,
1287c609719bSwdenk		FALSE if it is low.
1288c609719bSwdenk
1289b37c7e5eSwdenk		eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1290b37c7e5eSwdenk
1291c609719bSwdenk		I2C_SDA(bit)
1292c609719bSwdenk
1293c609719bSwdenk		If <bit> is TRUE, sets the I2C data line high. If it
1294c609719bSwdenk		is FALSE, it clears it (low).
1295c609719bSwdenk
1296b37c7e5eSwdenk		eg: #define I2C_SDA(bit) \
1297b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SDA; \
1298b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SDA
1299b37c7e5eSwdenk
1300c609719bSwdenk		I2C_SCL(bit)
1301c609719bSwdenk
1302c609719bSwdenk		If <bit> is TRUE, sets the I2C clock line high. If it
1303c609719bSwdenk		is FALSE, it clears it (low).
1304c609719bSwdenk
1305b37c7e5eSwdenk		eg: #define I2C_SCL(bit) \
1306b37c7e5eSwdenk			if(bit) immr->im_cpm.cp_pbdat |=  PB_SCL; \
1307b37c7e5eSwdenk			else	immr->im_cpm.cp_pbdat &= ~PB_SCL
1308b37c7e5eSwdenk
1309c609719bSwdenk		I2C_DELAY
1310c609719bSwdenk
1311c609719bSwdenk		This delay is invoked four times per clock cycle so this
1312c609719bSwdenk		controls the rate of data transfer.  The data rate thus
1313b37c7e5eSwdenk		is 1 / (I2C_DELAY * 4). Often defined to be something
1314b37c7e5eSwdenk		like:
1315b37c7e5eSwdenk
1316b37c7e5eSwdenk		#define I2C_DELAY  udelay(2)
1317c609719bSwdenk
131847cd00faSwdenk		CFG_I2C_INIT_BOARD
131947cd00faSwdenk
132047cd00faSwdenk		When a board is reset during an i2c bus transfer
132147cd00faSwdenk		chips might think that the current transfer is still
132247cd00faSwdenk		in progress. On some boards it is possible to access
132347cd00faSwdenk		the i2c SCLK line directly, either by using the
132447cd00faSwdenk		processor pin as a GPIO or by having a second pin
132547cd00faSwdenk		connected to the bus. If this option is defined a
132647cd00faSwdenk		custom i2c_init_board() routine in boards/xxx/board.c
132747cd00faSwdenk		is run early in the boot sequence.
132847cd00faSwdenk
132917ea1177Swdenk		CONFIG_I2CFAST (PPC405GP|PPC405EP only)
133017ea1177Swdenk
133117ea1177Swdenk		This option enables configuration of bi_iic_fast[] flags
133217ea1177Swdenk		in u-boot bd_info structure based on u-boot environment
133317ea1177Swdenk		variable "i2cfast". (see also i2cfast)
133417ea1177Swdenk
1335bb99ad6dSBen Warren		CONFIG_I2C_MULTI_BUS
1336bb99ad6dSBen Warren
1337bb99ad6dSBen Warren		This option allows the use of multiple I2C buses, each of which
1338bb99ad6dSBen Warren		must have a controller.  At any point in time, only one bus is
1339bb99ad6dSBen Warren		active.  To switch to a different bus, use the 'i2c dev' command.
1340bb99ad6dSBen Warren		Note that bus numbering is zero-based.
1341bb99ad6dSBen Warren
1342bb99ad6dSBen Warren		CFG_I2C_NOPROBES
1343bb99ad6dSBen Warren
1344bb99ad6dSBen Warren		This option specifies a list of I2C devices that will be skipped
1345bb99ad6dSBen Warren		when the 'i2c probe' command is issued (or 'iprobe' using the legacy
1346bb99ad6dSBen Warren		command).  If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device
1347bb99ad6dSBen Warren		pairs.	Otherwise, specify a 1D array of device addresses
1348bb99ad6dSBen Warren
1349bb99ad6dSBen Warren		e.g.
1350bb99ad6dSBen Warren			#undef	CONFIG_I2C_MULTI_BUS
1351bb99ad6dSBen Warren			#define CFG_I2C_NOPROBES	{0x50,0x68}
1352bb99ad6dSBen Warren
1353bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on a board with one I2C bus
1354bb99ad6dSBen Warren
1355bb99ad6dSBen Warren			#define	CONFIG_I2C_MULTI_BUS
1356bb99ad6dSBen Warren			#define CFG_I2C_MULTI_NOPROBES	{{0,0x50},{0,0x68},{1,0x54}}
1357bb99ad6dSBen Warren
1358bb99ad6dSBen Warren		will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1359bb99ad6dSBen Warren
1360be5e6181STimur Tabi		CFG_SPD_BUS_NUM
1361be5e6181STimur Tabi
1362be5e6181STimur Tabi		If defined, then this indicates the I2C bus number for DDR SPD.
1363be5e6181STimur Tabi		If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1364be5e6181STimur Tabi
13650dc018ecSStefan Roese		CFG_RTC_BUS_NUM
13660dc018ecSStefan Roese
13670dc018ecSStefan Roese		If defined, then this indicates the I2C bus number for the RTC.
13680dc018ecSStefan Roese		If not defined, then U-Boot assumes that RTC is on I2C bus 0.
13690dc018ecSStefan Roese
13700dc018ecSStefan Roese		CFG_DTT_BUS_NUM
13710dc018ecSStefan Roese
13720dc018ecSStefan Roese		If defined, then this indicates the I2C bus number for the DTT.
13730dc018ecSStefan Roese		If not defined, then U-Boot assumes that DTT is on I2C bus 0.
13740dc018ecSStefan Roese
1375be5e6181STimur Tabi		CONFIG_FSL_I2C
1376be5e6181STimur Tabi
1377be5e6181STimur Tabi		Define this option if you want to use Freescale's I2C driver in
13787817cb20SMarcel Ziswiler		drivers/i2c/fsl_i2c.c.
1379be5e6181STimur Tabi
1380be5e6181STimur Tabi
1381c609719bSwdenk- SPI Support:	CONFIG_SPI
1382c609719bSwdenk
1383c609719bSwdenk		Enables SPI driver (so far only tested with
1384c609719bSwdenk		SPI EEPROM, also an instance works with Crystal A/D and
1385c609719bSwdenk		D/As on the SACSng board)
1386c609719bSwdenk
1387c609719bSwdenk		CONFIG_SPI_X
1388c609719bSwdenk
1389c609719bSwdenk		Enables extended (16-bit) SPI EEPROM addressing.
1390c609719bSwdenk		(symmetrical to CONFIG_I2C_X)
1391c609719bSwdenk
1392c609719bSwdenk		CONFIG_SOFT_SPI
1393c609719bSwdenk
1394c609719bSwdenk		Enables a software (bit-bang) SPI driver rather than
1395c609719bSwdenk		using hardware support. This is a general purpose
1396c609719bSwdenk		driver that only requires three general I/O port pins
1397c609719bSwdenk		(two outputs, one input) to function. If this is
1398c609719bSwdenk		defined, the board configuration must define several
1399c609719bSwdenk		SPI configuration items (port pins to use, etc). For
1400c609719bSwdenk		an example, see include/configs/sacsng.h.
1401c609719bSwdenk
140204a9e118SBen Warren		CONFIG_HARD_SPI
140304a9e118SBen Warren
140404a9e118SBen Warren		Enables a hardware SPI driver for general-purpose reads
140504a9e118SBen Warren		and writes.  As with CONFIG_SOFT_SPI, the board configuration
140604a9e118SBen Warren		must define a list of chip-select function pointers.
140704a9e118SBen Warren		Currently supported on some MPC8xxx processors.  For an
140804a9e118SBen Warren		example, see include/configs/mpc8349emds.h.
140904a9e118SBen Warren
14100133502eSMatthias Fuchs- FPGA Support: CONFIG_FPGA
14110133502eSMatthias Fuchs
14120133502eSMatthias Fuchs		Enables FPGA subsystem.
14130133502eSMatthias Fuchs
14140133502eSMatthias Fuchs		CONFIG_FPGA_<vendor>
14150133502eSMatthias Fuchs
14160133502eSMatthias Fuchs		Enables support for specific chip vendors.
14170133502eSMatthias Fuchs		(ALTERA, XILINX)
14180133502eSMatthias Fuchs
14190133502eSMatthias Fuchs		CONFIG_FPGA_<family>
14200133502eSMatthias Fuchs
14210133502eSMatthias Fuchs		Enables support for FPGA family.
14220133502eSMatthias Fuchs		(SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
14230133502eSMatthias Fuchs
14240133502eSMatthias Fuchs		CONFIG_FPGA_COUNT
1425c609719bSwdenk
1426c609719bSwdenk		Specify the number of FPGA devices to support.
1427c609719bSwdenk
1428c609719bSwdenk		CFG_FPGA_PROG_FEEDBACK
1429c609719bSwdenk
1430c609719bSwdenk		Enable printing of hash marks during FPGA configuration.
1431c609719bSwdenk
1432c609719bSwdenk		CFG_FPGA_CHECK_BUSY
1433c609719bSwdenk
1434c609719bSwdenk		Enable checks on FPGA configuration interface busy
1435c609719bSwdenk		status by the configuration function. This option
1436c609719bSwdenk		will require a board or device specific function to
1437c609719bSwdenk		be written.
1438c609719bSwdenk
1439c609719bSwdenk		CONFIG_FPGA_DELAY
1440c609719bSwdenk
1441c609719bSwdenk		If defined, a function that provides delays in the FPGA
1442c609719bSwdenk		configuration driver.
1443c609719bSwdenk
1444c609719bSwdenk		CFG_FPGA_CHECK_CTRLC
1445c609719bSwdenk		Allow Control-C to interrupt FPGA configuration
1446c609719bSwdenk
1447c609719bSwdenk		CFG_FPGA_CHECK_ERROR
1448c609719bSwdenk
1449c609719bSwdenk		Check for configuration errors during FPGA bitfile
1450c609719bSwdenk		loading. For example, abort during Virtex II
1451c609719bSwdenk		configuration if the INIT_B line goes low (which
1452c609719bSwdenk		indicated a CRC error).
1453c609719bSwdenk
1454c609719bSwdenk		CFG_FPGA_WAIT_INIT
1455c609719bSwdenk
1456c609719bSwdenk		Maximum time to wait for the INIT_B line to deassert
1457c609719bSwdenk		after PROB_B has been deasserted during a Virtex II
1458c609719bSwdenk		FPGA configuration sequence. The default time is 500
1459c609719bSwdenk		mS.
1460c609719bSwdenk
1461c609719bSwdenk		CFG_FPGA_WAIT_BUSY
1462c609719bSwdenk
1463c609719bSwdenk		Maximum time to wait for BUSY to deassert during
1464c609719bSwdenk		Virtex II FPGA configuration. The default is 5 mS.
1465c609719bSwdenk
1466c609719bSwdenk		CFG_FPGA_WAIT_CONFIG
1467c609719bSwdenk
1468c609719bSwdenk		Time to wait after FPGA configuration. The default is
1469c609719bSwdenk		200 mS.
1470c609719bSwdenk
1471c609719bSwdenk- Configuration Management:
1472c609719bSwdenk		CONFIG_IDENT_STRING
1473c609719bSwdenk
1474c609719bSwdenk		If defined, this string will be added to the U-Boot
1475c609719bSwdenk		version information (U_BOOT_VERSION)
1476c609719bSwdenk
1477c609719bSwdenk- Vendor Parameter Protection:
1478c609719bSwdenk
1479c609719bSwdenk		U-Boot considers the values of the environment
1480c609719bSwdenk		variables "serial#" (Board Serial Number) and
14817152b1d0Swdenk		"ethaddr" (Ethernet Address) to be parameters that
1482c609719bSwdenk		are set once by the board vendor / manufacturer, and
1483c609719bSwdenk		protects these variables from casual modification by
1484c609719bSwdenk		the user. Once set, these variables are read-only,
1485c609719bSwdenk		and write or delete attempts are rejected. You can
1486c609719bSwdenk		change this behviour:
1487c609719bSwdenk
1488c609719bSwdenk		If CONFIG_ENV_OVERWRITE is #defined in your config
1489c609719bSwdenk		file, the write protection for vendor parameters is
149047cd00faSwdenk		completely disabled. Anybody can change or delete
1491c609719bSwdenk		these parameters.
1492c609719bSwdenk
1493c609719bSwdenk		Alternatively, if you #define _both_ CONFIG_ETHADDR
1494c609719bSwdenk		_and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1495c609719bSwdenk		ethernet address is installed in the environment,
1496c609719bSwdenk		which can be changed exactly ONCE by the user. [The
1497c609719bSwdenk		serial# is unaffected by this, i. e. it remains
1498c609719bSwdenk		read-only.]
1499c609719bSwdenk
1500c609719bSwdenk- Protected RAM:
1501c609719bSwdenk		CONFIG_PRAM
1502c609719bSwdenk
1503c609719bSwdenk		Define this variable to enable the reservation of
1504c609719bSwdenk		"protected RAM", i. e. RAM which is not overwritten
1505c609719bSwdenk		by U-Boot. Define CONFIG_PRAM to hold the number of
1506c609719bSwdenk		kB you want to reserve for pRAM. You can overwrite
1507c609719bSwdenk		this default value by defining an environment
1508c609719bSwdenk		variable "pram" to the number of kB you want to
1509c609719bSwdenk		reserve. Note that the board info structure will
1510c609719bSwdenk		still show the full amount of RAM. If pRAM is
1511c609719bSwdenk		reserved, a new environment variable "mem" will
1512c609719bSwdenk		automatically be defined to hold the amount of
1513c609719bSwdenk		remaining RAM in a form that can be passed as boot
1514c609719bSwdenk		argument to Linux, for instance like that:
1515c609719bSwdenk
1516fe126d8bSWolfgang Denk			setenv bootargs ... mem=\${mem}
1517c609719bSwdenk			saveenv
1518c609719bSwdenk
1519c609719bSwdenk		This way you can tell Linux not to use this memory,
1520c609719bSwdenk		either, which results in a memory region that will
1521c609719bSwdenk		not be affected by reboots.
1522c609719bSwdenk
1523c609719bSwdenk		*WARNING* If your board configuration uses automatic
1524c609719bSwdenk		detection of the RAM size, you must make sure that
1525c609719bSwdenk		this memory test is non-destructive. So far, the
1526c609719bSwdenk		following board configurations are known to be
1527c609719bSwdenk		"pRAM-clean":
1528c609719bSwdenk
1529c609719bSwdenk			ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1530c609719bSwdenk			HERMES, IP860, RPXlite, LWMON, LANTEC,
1531c609719bSwdenk			PCU_E, FLAGADM, TQM8260
1532c609719bSwdenk
1533c609719bSwdenk- Error Recovery:
1534c609719bSwdenk		CONFIG_PANIC_HANG
1535c609719bSwdenk
1536c609719bSwdenk		Define this variable to stop the system in case of a
1537c609719bSwdenk		fatal error, so that you have to reset it manually.
1538c609719bSwdenk		This is probably NOT a good idea for an embedded
1539c609719bSwdenk		system where you want to system to reboot
1540c609719bSwdenk		automatically as fast as possible, but it may be
1541c609719bSwdenk		useful during development since you can try to debug
1542c609719bSwdenk		the conditions that lead to the situation.
1543c609719bSwdenk
1544c609719bSwdenk		CONFIG_NET_RETRY_COUNT
1545c609719bSwdenk
1546c609719bSwdenk		This variable defines the number of retries for
1547c609719bSwdenk		network operations like ARP, RARP, TFTP, or BOOTP
1548c609719bSwdenk		before giving up the operation. If not defined, a
1549c609719bSwdenk		default value of 5 is used.
1550c609719bSwdenk
1551c609719bSwdenk- Command Interpreter:
15528078f1a5SWolfgang Denk		CONFIG_AUTO_COMPLETE
155304a85b3bSwdenk
155404a85b3bSwdenk		Enable auto completion of commands using TAB.
155504a85b3bSwdenk
15568078f1a5SWolfgang Denk		Note that this feature has NOT been implemented yet
15578078f1a5SWolfgang Denk		for the "hush" shell.
15588078f1a5SWolfgang Denk
15598078f1a5SWolfgang Denk
1560c609719bSwdenk		CFG_HUSH_PARSER
1561c609719bSwdenk
1562c609719bSwdenk		Define this variable to enable the "hush" shell (from
1563c609719bSwdenk		Busybox) as command line interpreter, thus enabling
1564c609719bSwdenk		powerful command line syntax like
1565c609719bSwdenk		if...then...else...fi conditionals or `&&' and '||'
1566c609719bSwdenk		constructs ("shell scripts").
1567c609719bSwdenk
1568c609719bSwdenk		If undefined, you get the old, much simpler behaviour
1569c609719bSwdenk		with a somewhat smaller memory footprint.
1570c609719bSwdenk
1571c609719bSwdenk
1572c609719bSwdenk		CFG_PROMPT_HUSH_PS2
1573c609719bSwdenk
1574c609719bSwdenk		This defines the secondary prompt string, which is
1575c609719bSwdenk		printed when the command interpreter needs more input
1576c609719bSwdenk		to complete a command. Usually "> ".
1577c609719bSwdenk
1578c609719bSwdenk	Note:
1579c609719bSwdenk
1580c609719bSwdenk		In the current implementation, the local variables
1581c609719bSwdenk		space and global environment variables space are
1582c609719bSwdenk		separated. Local variables are those you define by
15833b57fe0aSwdenk		simply typing `name=value'. To access a local
1584c609719bSwdenk		variable later on, you have write `$name' or
15853b57fe0aSwdenk		`${name}'; to execute the contents of a variable
15863b57fe0aSwdenk		directly type `$name' at the command prompt.
1587c609719bSwdenk
1588c609719bSwdenk		Global environment variables are those you use
1589c609719bSwdenk		setenv/printenv to work with. To run a command stored
1590c609719bSwdenk		in such a variable, you need to use the run command,
1591c609719bSwdenk		and you must not use the '$' sign to access them.
1592c609719bSwdenk
1593c609719bSwdenk		To store commands and special characters in a
1594c609719bSwdenk		variable, please use double quotation marks
1595c609719bSwdenk		surrounding the whole text of the variable, instead
1596c609719bSwdenk		of the backslashes before semicolons and special
1597c609719bSwdenk		symbols.
1598c609719bSwdenk
1599aa0c71acSWolfgang Denk- Commandline Editing and History:
1600aa0c71acSWolfgang Denk		CONFIG_CMDLINE_EDITING
1601aa0c71acSWolfgang Denk
1602aa0c71acSWolfgang Denk		Enable editiong and History functions for interactive
1603aa0c71acSWolfgang Denk		commandline input operations
1604aa0c71acSWolfgang Denk
1605a8c7c708Swdenk- Default Environment:
1606c609719bSwdenk		CONFIG_EXTRA_ENV_SETTINGS
1607c609719bSwdenk
1608c609719bSwdenk		Define this to contain any number of null terminated
1609c609719bSwdenk		strings (variable = value pairs) that will be part of
16107152b1d0Swdenk		the default environment compiled into the boot image.
16112262cfeeSwdenk
1612c609719bSwdenk		For example, place something like this in your
1613c609719bSwdenk		board's config file:
1614c609719bSwdenk
1615c609719bSwdenk		#define CONFIG_EXTRA_ENV_SETTINGS \
1616c609719bSwdenk			"myvar1=value1\0" \
1617c609719bSwdenk			"myvar2=value2\0"
1618c609719bSwdenk
1619c609719bSwdenk		Warning: This method is based on knowledge about the
1620c609719bSwdenk		internal format how the environment is stored by the
16212262cfeeSwdenk		U-Boot code. This is NOT an official, exported
1622c609719bSwdenk		interface! Although it is unlikely that this format
16237152b1d0Swdenk		will change soon, there is no guarantee either.
1624c609719bSwdenk		You better know what you are doing here.
1625c609719bSwdenk
1626c609719bSwdenk		Note: overly (ab)use of the default environment is
1627c609719bSwdenk		discouraged. Make sure to check other ways to preset
1628c609719bSwdenk		the environment like the autoscript function or the
1629c609719bSwdenk		boot command first.
1630c609719bSwdenk
1631a8c7c708Swdenk- DataFlash Support:
16322abbe075Swdenk		CONFIG_HAS_DATAFLASH
16332abbe075Swdenk
16342abbe075Swdenk		Defining this option enables DataFlash features and
16352abbe075Swdenk		allows to read/write in Dataflash via the standard
16362abbe075Swdenk		commands cp, md...
16372abbe075Swdenk
16383f85ce27Swdenk- SystemACE Support:
16393f85ce27Swdenk		CONFIG_SYSTEMACE
16403f85ce27Swdenk
16413f85ce27Swdenk		Adding this option adds support for Xilinx SystemACE
16423f85ce27Swdenk		chips attached via some sort of local bus. The address
16433f85ce27Swdenk		of the chip must alsh be defined in the
16443f85ce27Swdenk		CFG_SYSTEMACE_BASE macro. For example:
16453f85ce27Swdenk
16463f85ce27Swdenk		#define CONFIG_SYSTEMACE
16473f85ce27Swdenk		#define CFG_SYSTEMACE_BASE 0xf0000000
16483f85ce27Swdenk
16493f85ce27Swdenk		When SystemACE support is added, the "ace" device type
16503f85ce27Swdenk		becomes available to the fat commands, i.e. fatls.
16513f85ce27Swdenk
1652ecb0ccd9SWolfgang Denk- TFTP Fixed UDP Port:
1653ecb0ccd9SWolfgang Denk		CONFIG_TFTP_PORT
1654ecb0ccd9SWolfgang Denk
165528cb9375SWolfgang Denk		If this is defined, the environment variable tftpsrcp
1656ecb0ccd9SWolfgang Denk		is used to supply the TFTP UDP source port value.
165728cb9375SWolfgang Denk		If tftpsrcp isn't defined, the normal pseudo-random port
1658ecb0ccd9SWolfgang Denk		number generator is used.
1659ecb0ccd9SWolfgang Denk
166028cb9375SWolfgang Denk		Also, the environment variable tftpdstp is used to supply
166128cb9375SWolfgang Denk		the TFTP UDP destination port value.  If tftpdstp isn't
166228cb9375SWolfgang Denk		defined, the normal port 69 is used.
166328cb9375SWolfgang Denk
166428cb9375SWolfgang Denk		The purpose for tftpsrcp is to allow a TFTP server to
1665ecb0ccd9SWolfgang Denk		blindly start the TFTP transfer using the pre-configured
1666ecb0ccd9SWolfgang Denk		target IP address and UDP port. This has the effect of
1667ecb0ccd9SWolfgang Denk		"punching through" the (Windows XP) firewall, allowing
1668ecb0ccd9SWolfgang Denk		the remainder of the TFTP transfer to proceed normally.
1669ecb0ccd9SWolfgang Denk		A better solution is to properly configure the firewall,
1670ecb0ccd9SWolfgang Denk		but sometimes that is not allowed.
1671ecb0ccd9SWolfgang Denk
1672a8c7c708Swdenk- Show boot progress:
1673c609719bSwdenk		CONFIG_SHOW_BOOT_PROGRESS
1674c609719bSwdenk
1675c609719bSwdenk		Defining this option allows to add some board-
1676c609719bSwdenk		specific code (calling a user-provided function
1677c609719bSwdenk		"show_boot_progress(int)") that enables you to show
1678c609719bSwdenk		the system's boot progress on some display (for
1679c609719bSwdenk		example, some LED's) on your board. At the moment,
1680c609719bSwdenk		the following checkpoints are implemented:
1681c609719bSwdenk
16821372cce2SMarian BalakowiczLegacy uImage format:
16831372cce2SMarian Balakowicz
1684c609719bSwdenk  Arg	Where			When
1685c609719bSwdenk    1	common/cmd_bootm.c	before attempting to boot an image
1686c609719bSwdenk   -1	common/cmd_bootm.c	Image header has bad	 magic number
1687c609719bSwdenk    2	common/cmd_bootm.c	Image header has correct magic number
1688c609719bSwdenk   -2	common/cmd_bootm.c	Image header has bad	 checksum
1689c609719bSwdenk    3	common/cmd_bootm.c	Image header has correct checksum
1690c609719bSwdenk   -3	common/cmd_bootm.c	Image data   has bad	 checksum
1691c609719bSwdenk    4	common/cmd_bootm.c	Image data   has correct checksum
1692c609719bSwdenk   -4	common/cmd_bootm.c	Image is for unsupported architecture
1693c609719bSwdenk    5	common/cmd_bootm.c	Architecture check OK
16941372cce2SMarian Balakowicz   -5	common/cmd_bootm.c	Wrong Image Type (not kernel, multi)
1695c609719bSwdenk    6	common/cmd_bootm.c	Image Type check OK
1696c609719bSwdenk   -6	common/cmd_bootm.c	gunzip uncompression error
1697c609719bSwdenk   -7	common/cmd_bootm.c	Unimplemented compression type
1698c609719bSwdenk    7	common/cmd_bootm.c	Uncompression OK
16991372cce2SMarian Balakowicz    8	common/cmd_bootm.c	No uncompress/copy overwrite error
1700c609719bSwdenk   -9	common/cmd_bootm.c	Unsupported OS (not Linux, BSD, VxWorks, QNX)
17011372cce2SMarian Balakowicz
17021372cce2SMarian Balakowicz    9	common/image.c		Start initial ramdisk verification
17031372cce2SMarian Balakowicz  -10	common/image.c		Ramdisk header has bad	   magic number
17041372cce2SMarian Balakowicz  -11	common/image.c		Ramdisk header has bad	   checksum
17051372cce2SMarian Balakowicz   10	common/image.c		Ramdisk header is OK
17061372cce2SMarian Balakowicz  -12	common/image.c		Ramdisk data   has bad	   checksum
17071372cce2SMarian Balakowicz   11	common/image.c		Ramdisk data   has correct checksum
17081372cce2SMarian Balakowicz   12	common/image.c		Ramdisk verification complete, start loading
17091372cce2SMarian Balakowicz  -13	common/image.c		Wrong Image Type (not PPC Linux Ramdisk)
17101372cce2SMarian Balakowicz   13	common/image.c		Start multifile image verification
17111372cce2SMarian Balakowicz   14	common/image.c		No initial ramdisk, no multifile, continue.
17121372cce2SMarian Balakowicz
17131372cce2SMarian Balakowicz   15	lib_<arch>/bootm.c	All preparation done, transferring control to OS
1714c609719bSwdenk
171563e73c9aSwdenk  -30	lib_ppc/board.c		Fatal error, hang the system
171663e73c9aSwdenk  -31	post/post.c		POST test failed, detected by post_output_backlog()
171763e73c9aSwdenk  -32	post/post.c		POST test failed, detected by post_run_single()
171863e73c9aSwdenk
1719566a494fSHeiko Schocher   34	common/cmd_doc.c	before loading a Image from a DOC device
1720566a494fSHeiko Schocher  -35	common/cmd_doc.c	Bad usage of "doc" command
1721566a494fSHeiko Schocher   35	common/cmd_doc.c	correct usage of "doc" command
1722566a494fSHeiko Schocher  -36	common/cmd_doc.c	No boot device
1723566a494fSHeiko Schocher   36	common/cmd_doc.c	correct boot device
1724566a494fSHeiko Schocher  -37	common/cmd_doc.c	Unknown Chip ID on boot device
1725566a494fSHeiko Schocher   37	common/cmd_doc.c	correct chip ID found, device available
1726566a494fSHeiko Schocher  -38	common/cmd_doc.c	Read Error on boot device
1727566a494fSHeiko Schocher   38	common/cmd_doc.c	reading Image header from DOC device OK
1728566a494fSHeiko Schocher  -39	common/cmd_doc.c	Image header has bad magic number
1729566a494fSHeiko Schocher   39	common/cmd_doc.c	Image header has correct magic number
1730566a494fSHeiko Schocher  -40	common/cmd_doc.c	Error reading Image from DOC device
1731566a494fSHeiko Schocher   40	common/cmd_doc.c	Image header has correct magic number
1732566a494fSHeiko Schocher   41	common/cmd_ide.c	before loading a Image from a IDE device
1733566a494fSHeiko Schocher  -42	common/cmd_ide.c	Bad usage of "ide" command
1734566a494fSHeiko Schocher   42	common/cmd_ide.c	correct usage of "ide" command
1735566a494fSHeiko Schocher  -43	common/cmd_ide.c	No boot device
1736566a494fSHeiko Schocher   43	common/cmd_ide.c	boot device found
1737566a494fSHeiko Schocher  -44	common/cmd_ide.c	Device not available
1738566a494fSHeiko Schocher   44	common/cmd_ide.c	Device available
1739566a494fSHeiko Schocher  -45	common/cmd_ide.c	wrong partition selected
1740566a494fSHeiko Schocher   45	common/cmd_ide.c	partition selected
1741566a494fSHeiko Schocher  -46	common/cmd_ide.c	Unknown partition table
1742566a494fSHeiko Schocher   46	common/cmd_ide.c	valid partition table found
1743566a494fSHeiko Schocher  -47	common/cmd_ide.c	Invalid partition type
1744566a494fSHeiko Schocher   47	common/cmd_ide.c	correct partition type
1745566a494fSHeiko Schocher  -48	common/cmd_ide.c	Error reading Image Header on boot device
1746566a494fSHeiko Schocher   48	common/cmd_ide.c	reading Image Header from IDE device OK
1747566a494fSHeiko Schocher  -49	common/cmd_ide.c	Image header has bad magic number
1748566a494fSHeiko Schocher   49	common/cmd_ide.c	Image header has correct magic number
1749566a494fSHeiko Schocher  -50	common/cmd_ide.c	Image header has bad	 checksum
1750566a494fSHeiko Schocher   50	common/cmd_ide.c	Image header has correct checksum
1751566a494fSHeiko Schocher  -51	common/cmd_ide.c	Error reading Image from IDE device
1752566a494fSHeiko Schocher   51	common/cmd_ide.c	reading Image from IDE device OK
1753566a494fSHeiko Schocher   52	common/cmd_nand.c	before loading a Image from a NAND device
1754566a494fSHeiko Schocher  -53	common/cmd_nand.c	Bad usage of "nand" command
1755566a494fSHeiko Schocher   53	common/cmd_nand.c	correct usage of "nand" command
1756566a494fSHeiko Schocher  -54	common/cmd_nand.c	No boot device
1757566a494fSHeiko Schocher   54	common/cmd_nand.c	boot device found
1758566a494fSHeiko Schocher  -55	common/cmd_nand.c	Unknown Chip ID on boot device
1759566a494fSHeiko Schocher   55	common/cmd_nand.c	correct chip ID found, device available
1760566a494fSHeiko Schocher  -56	common/cmd_nand.c	Error reading Image Header on boot device
1761566a494fSHeiko Schocher   56	common/cmd_nand.c	reading Image Header from NAND device OK
1762566a494fSHeiko Schocher  -57	common/cmd_nand.c	Image header has bad magic number
1763566a494fSHeiko Schocher   57	common/cmd_nand.c	Image header has correct magic number
1764566a494fSHeiko Schocher  -58	common/cmd_nand.c	Error reading Image from NAND device
1765566a494fSHeiko Schocher   58	common/cmd_nand.c	reading Image from NAND device OK
1766c609719bSwdenk
1767566a494fSHeiko Schocher  -60	common/env_common.c	Environment has a bad CRC, using default
1768c609719bSwdenk
1769566a494fSHeiko Schocher   64	net/eth.c		starting with Ethernetconfiguration.
1770566a494fSHeiko Schocher  -64	net/eth.c		no Ethernet found.
1771566a494fSHeiko Schocher   65	net/eth.c		Ethernet found.
1772206c60cbSwdenk
1773566a494fSHeiko Schocher  -80	common/cmd_net.c	usage wrong
1774566a494fSHeiko Schocher   80	common/cmd_net.c	before calling NetLoop()
1775566a494fSHeiko Schocher  -81	common/cmd_net.c	some error in NetLoop() occured
1776566a494fSHeiko Schocher   81	common/cmd_net.c	NetLoop() back without error
1777566a494fSHeiko Schocher  -82	common/cmd_net.c	size == 0 (File with size 0 loaded)
1778566a494fSHeiko Schocher   82	common/cmd_net.c	trying automatic boot
1779566a494fSHeiko Schocher   83	common/cmd_net.c	running autoscript
1780566a494fSHeiko Schocher  -83	common/cmd_net.c	some error in automatic boot or autoscript
1781566a494fSHeiko Schocher   84	common/cmd_net.c	end without errors
1782c609719bSwdenk
17831372cce2SMarian BalakowiczFIT uImage format:
17841372cce2SMarian Balakowicz
17851372cce2SMarian Balakowicz  Arg	Where			When
17861372cce2SMarian Balakowicz  100	common/cmd_bootm.c	Kernel FIT Image has correct format
17871372cce2SMarian Balakowicz -100	common/cmd_bootm.c	Kernel FIT Image has incorrect format
17881372cce2SMarian Balakowicz  101	common/cmd_bootm.c	No Kernel subimage unit name, using configuration
17891372cce2SMarian Balakowicz -101	common/cmd_bootm.c	Can't get configuration for kernel subimage
17901372cce2SMarian Balakowicz  102	common/cmd_bootm.c	Kernel unit name specified
17911372cce2SMarian Balakowicz -103	common/cmd_bootm.c	Can't get kernel subimage node offset
1792f773bea8SMarian Balakowicz  103	common/cmd_bootm.c	Found configuration node
17931372cce2SMarian Balakowicz  104	common/cmd_bootm.c	Got kernel subimage node offset
17941372cce2SMarian Balakowicz -104	common/cmd_bootm.c	Kernel subimage hash verification failed
17951372cce2SMarian Balakowicz  105	common/cmd_bootm.c	Kernel subimage hash verification OK
17961372cce2SMarian Balakowicz -105	common/cmd_bootm.c	Kernel subimage is for unsupported architecture
17971372cce2SMarian Balakowicz  106	common/cmd_bootm.c	Architecture check OK
17981372cce2SMarian Balakowicz -106	common/cmd_bootm.c	Kernel subimage has wrong typea
17991372cce2SMarian Balakowicz  107	common/cmd_bootm.c	Kernel subimge type OK
18001372cce2SMarian Balakowicz -107	common/cmd_bootm.c	Can't get kernel subimage data/size
18011372cce2SMarian Balakowicz  108	common/cmd_bootm.c	Got kernel subimage data/size
18021372cce2SMarian Balakowicz -108	common/cmd_bootm.c	Wrong image type (not legacy, FIT)
18031372cce2SMarian Balakowicz -109	common/cmd_bootm.c	Can't get kernel subimage type
18041372cce2SMarian Balakowicz -110	common/cmd_bootm.c	Can't get kernel subimage comp
18051372cce2SMarian Balakowicz -111	common/cmd_bootm.c	Can't get kernel subimage os
18061372cce2SMarian Balakowicz -112	common/cmd_bootm.c	Can't get kernel subimage load address
18071372cce2SMarian Balakowicz -113	common/cmd_bootm.c	Image uncompress/copy overwrite error
18081372cce2SMarian Balakowicz
18091372cce2SMarian Balakowicz  120	common/image.c		Start initial ramdisk verification
18101372cce2SMarian Balakowicz -120	common/image.c		Ramdisk FIT image has incorrect format
18111372cce2SMarian Balakowicz  121	common/image.c		Ramdisk FIT image has correct format
18121372cce2SMarian Balakowicz  122	common/image.c		No Ramdisk subimage unit name, using configuration
18131372cce2SMarian Balakowicz -122	common/image.c		Can't get configuration for ramdisk subimage
18141372cce2SMarian Balakowicz  123	common/image.c		Ramdisk unit name specified
18151372cce2SMarian Balakowicz -124	common/image.c		Can't get ramdisk subimage node offset
18161372cce2SMarian Balakowicz  125	common/image.c		Got ramdisk subimage node offset
18171372cce2SMarian Balakowicz -125	common/image.c		Ramdisk subimage hash verification failed
18181372cce2SMarian Balakowicz  126	common/image.c		Ramdisk subimage hash verification OK
18191372cce2SMarian Balakowicz -126	common/image.c		Ramdisk subimage for unsupported architecture
18201372cce2SMarian Balakowicz  127	common/image.c		Architecture check OK
18211372cce2SMarian Balakowicz -127	common/image.c		Can't get ramdisk subimage data/size
18221372cce2SMarian Balakowicz  128	common/image.c		Got ramdisk subimage data/size
18231372cce2SMarian Balakowicz  129	common/image.c		Can't get ramdisk load address
18241372cce2SMarian Balakowicz -129	common/image.c		Got ramdisk load address
18251372cce2SMarian Balakowicz
18261372cce2SMarian Balakowicz -130	common/cmd_doc.c	Icorrect FIT image format
18271372cce2SMarian Balakowicz  131	common/cmd_doc.c	FIT image format OK
18281372cce2SMarian Balakowicz
18291372cce2SMarian Balakowicz -140	common/cmd_ide.c	Icorrect FIT image format
18301372cce2SMarian Balakowicz  141	common/cmd_ide.c	FIT image format OK
18311372cce2SMarian Balakowicz
18321372cce2SMarian Balakowicz -150	common/cmd_nand.c	Icorrect FIT image format
18331372cce2SMarian Balakowicz  151	common/cmd_nand.c	FIT image format OK
18341372cce2SMarian Balakowicz
18351372cce2SMarian Balakowicz
1836c609719bSwdenkModem Support:
1837c609719bSwdenk--------------
1838c609719bSwdenk
183985ec0bccSwdenk[so far only for SMDK2400 and TRAB boards]
1840c609719bSwdenk
1841c609719bSwdenk- Modem support endable:
1842c609719bSwdenk		CONFIG_MODEM_SUPPORT
1843c609719bSwdenk
1844c609719bSwdenk- RTS/CTS Flow control enable:
1845c609719bSwdenk		CONFIG_HWFLOW
1846c609719bSwdenk
1847c609719bSwdenk- Modem debug support:
1848c609719bSwdenk		CONFIG_MODEM_SUPPORT_DEBUG
1849c609719bSwdenk
1850c609719bSwdenk		Enables debugging stuff (char screen[1024], dbg())
1851c609719bSwdenk		for modem support. Useful only with BDI2000.
1852c609719bSwdenk
1853a8c7c708Swdenk- Interrupt support (PPC):
1854a8c7c708Swdenk
1855a8c7c708Swdenk		There are common interrupt_init() and timer_interrupt()
1856a8c7c708Swdenk		for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1857a8c7c708Swdenk		for cpu specific initialization. interrupt_init_cpu()
1858a8c7c708Swdenk		should set decrementer_count to appropriate value. If
1859a8c7c708Swdenk		cpu resets decrementer automatically after interrupt
1860a8c7c708Swdenk		(ppc4xx) it should set decrementer_count to zero.
1861a8c7c708Swdenk		timer_interrupt() calls timer_interrupt_cpu() for cpu
1862a8c7c708Swdenk		specific handling. If board has watchdog / status_led
1863a8c7c708Swdenk		/ other_activity_monitor it works automatically from
1864a8c7c708Swdenk		general timer_interrupt().
1865a8c7c708Swdenk
1866c609719bSwdenk- General:
1867c609719bSwdenk
1868c609719bSwdenk		In the target system modem support is enabled when a
1869c609719bSwdenk		specific key (key combination) is pressed during
1870c609719bSwdenk		power-on. Otherwise U-Boot will boot normally
1871c609719bSwdenk		(autoboot). The key_pressed() fuction is called from
1872c609719bSwdenk		board_init(). Currently key_pressed() is a dummy
1873c609719bSwdenk		function, returning 1 and thus enabling modem
1874c609719bSwdenk		initialization.
1875c609719bSwdenk
1876c609719bSwdenk		If there are no modem init strings in the
1877c609719bSwdenk		environment, U-Boot proceed to autoboot; the
1878c609719bSwdenk		previous output (banner, info printfs) will be
1879c609719bSwdenk		supressed, though.
1880c609719bSwdenk
1881c609719bSwdenk		See also: doc/README.Modem
1882c609719bSwdenk
1883c609719bSwdenk
1884c609719bSwdenkConfiguration Settings:
1885c609719bSwdenk-----------------------
1886c609719bSwdenk
1887c609719bSwdenk- CFG_LONGHELP: Defined when you want long help messages included;
1888c609719bSwdenk		undefine this when you're short of memory.
1889c609719bSwdenk
1890c609719bSwdenk- CFG_PROMPT:	This is what U-Boot prints on the console to
1891c609719bSwdenk		prompt for user input.
1892c609719bSwdenk
1893c609719bSwdenk- CFG_CBSIZE:	Buffer size for input from the Console
1894c609719bSwdenk
1895c609719bSwdenk- CFG_PBSIZE:	Buffer size for Console output
1896c609719bSwdenk
1897c609719bSwdenk- CFG_MAXARGS:	max. Number of arguments accepted for monitor commands
1898c609719bSwdenk
1899c609719bSwdenk- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1900c609719bSwdenk		the application (usually a Linux kernel) when it is
1901c609719bSwdenk		booted
1902c609719bSwdenk
1903c609719bSwdenk- CFG_BAUDRATE_TABLE:
1904c609719bSwdenk		List of legal baudrate settings for this board.
1905c609719bSwdenk
1906c609719bSwdenk- CFG_CONSOLE_INFO_QUIET
1907c609719bSwdenk		Suppress display of console information at boot.
1908c609719bSwdenk
1909c609719bSwdenk- CFG_CONSOLE_IS_IN_ENV
1910c609719bSwdenk		If the board specific function
1911c609719bSwdenk			extern int overwrite_console (void);
1912c609719bSwdenk		returns 1, the stdin, stderr and stdout are switched to the
1913c609719bSwdenk		serial port, else the settings in the environment are used.
1914c609719bSwdenk
1915c609719bSwdenk- CFG_CONSOLE_OVERWRITE_ROUTINE
1916c609719bSwdenk		Enable the call to overwrite_console().
1917c609719bSwdenk
1918c609719bSwdenk- CFG_CONSOLE_ENV_OVERWRITE
1919c609719bSwdenk		Enable overwrite of previous console environment settings.
1920c609719bSwdenk
1921c609719bSwdenk- CFG_MEMTEST_START, CFG_MEMTEST_END:
1922c609719bSwdenk		Begin and End addresses of the area used by the
1923c609719bSwdenk		simple memory test.
1924c609719bSwdenk
1925c609719bSwdenk- CFG_ALT_MEMTEST:
1926c609719bSwdenk		Enable an alternate, more extensive memory test.
1927c609719bSwdenk
19285f535fe1Swdenk- CFG_MEMTEST_SCRATCH:
19295f535fe1Swdenk		Scratch address used by the alternate memory test
19305f535fe1Swdenk		You only need to set this if address zero isn't writeable
19315f535fe1Swdenk
193214f73ca6SStefan Roese- CFG_MEM_TOP_HIDE (PPC only):
193314f73ca6SStefan Roese		If CFG_MEM_TOP_HIDE is defined in the board config header,
193414f73ca6SStefan Roese		this specified memory area will get subtracted from the top
193514f73ca6SStefan Roese		(end) of ram and won't get "touched" at all by U-Boot. By
193614f73ca6SStefan Roese		fixing up gd->ram_size the Linux kernel should gets passed
193714f73ca6SStefan Roese		the now "corrected" memory size and won't touch it either.
193814f73ca6SStefan Roese		This should work for arch/ppc and arch/powerpc. Only Linux
1939*5e12e75dSStefan Roese		board ports in arch/powerpc with bootwrapper support that
194014f73ca6SStefan Roese		recalculate the memory size from the SDRAM controller setup
1941*5e12e75dSStefan Roese		will have to get fixed in Linux additionally.
194214f73ca6SStefan Roese
194314f73ca6SStefan Roese		This option can be used as a workaround for the 440EPx/GRx
194414f73ca6SStefan Roese		CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
194514f73ca6SStefan Roese		be touched.
194614f73ca6SStefan Roese
194714f73ca6SStefan Roese		WARNING: Please make sure that this value is a multiple of
194814f73ca6SStefan Roese		the Linux page size (normally 4k). If this is not the case,
194914f73ca6SStefan Roese		then the end address of the Linux memory will be located at a
195014f73ca6SStefan Roese		non page size aligned address and this could cause major
195114f73ca6SStefan Roese		problems.
195214f73ca6SStefan Roese
1953c609719bSwdenk- CFG_TFTP_LOADADDR:
1954c609719bSwdenk		Default load address for network file downloads
1955c609719bSwdenk
1956c609719bSwdenk- CFG_LOADS_BAUD_CHANGE:
1957c609719bSwdenk		Enable temporary baudrate change while serial download
1958c609719bSwdenk
1959c609719bSwdenk- CFG_SDRAM_BASE:
1960c609719bSwdenk		Physical start address of SDRAM. _Must_ be 0 here.
1961c609719bSwdenk
1962c609719bSwdenk- CFG_MBIO_BASE:
1963c609719bSwdenk		Physical start address of Motherboard I/O (if using a
1964c609719bSwdenk		Cogent motherboard)
1965c609719bSwdenk
1966c609719bSwdenk- CFG_FLASH_BASE:
1967c609719bSwdenk		Physical start address of Flash memory.
1968c609719bSwdenk
1969c609719bSwdenk- CFG_MONITOR_BASE:
1970c609719bSwdenk		Physical start address of boot monitor code (set by
1971c609719bSwdenk		make config files to be same as the text base address
1972c609719bSwdenk		(TEXT_BASE) used when linking) - same as
1973c609719bSwdenk		CFG_FLASH_BASE when booting from flash.
1974c609719bSwdenk
1975c609719bSwdenk- CFG_MONITOR_LEN:
19763b57fe0aSwdenk		Size of memory reserved for monitor code, used to
19773b57fe0aSwdenk		determine _at_compile_time_ (!) if the environment is
19783b57fe0aSwdenk		embedded within the U-Boot image, or in a separate
19793b57fe0aSwdenk		flash sector.
1980c609719bSwdenk
1981c609719bSwdenk- CFG_MALLOC_LEN:
1982c609719bSwdenk		Size of DRAM reserved for malloc() use.
1983c609719bSwdenk
198415940c9aSStefan Roese- CFG_BOOTM_LEN:
198515940c9aSStefan Roese		Normally compressed uImages are limited to an
198615940c9aSStefan Roese		uncompressed size of 8 MBytes. If this is not enough,
198715940c9aSStefan Roese		you can define CFG_BOOTM_LEN in your board config file
198815940c9aSStefan Roese		to adjust this setting to your needs.
1989c609719bSwdenk
1990c609719bSwdenk- CFG_BOOTMAPSZ:
1991c609719bSwdenk		Maximum size of memory mapped by the startup code of
1992c609719bSwdenk		the Linux kernel; all data that must be processed by
1993c609719bSwdenk		the Linux kernel (bd_info, boot arguments, eventually
1994c609719bSwdenk		initrd image) must be put below this limit.
1995c609719bSwdenk
1996c609719bSwdenk- CFG_MAX_FLASH_BANKS:
1997c609719bSwdenk		Max number of Flash memory banks
1998c609719bSwdenk
1999c609719bSwdenk- CFG_MAX_FLASH_SECT:
2000c609719bSwdenk		Max number of sectors on a Flash chip
2001c609719bSwdenk
2002c609719bSwdenk- CFG_FLASH_ERASE_TOUT:
2003c609719bSwdenk		Timeout for Flash erase operations (in ms)
2004c609719bSwdenk
2005c609719bSwdenk- CFG_FLASH_WRITE_TOUT:
2006c609719bSwdenk		Timeout for Flash write operations (in ms)
2007c609719bSwdenk
20088564acf9Swdenk- CFG_FLASH_LOCK_TOUT
20098564acf9Swdenk		Timeout for Flash set sector lock bit operation (in ms)
20108564acf9Swdenk
20118564acf9Swdenk- CFG_FLASH_UNLOCK_TOUT
20128564acf9Swdenk		Timeout for Flash clear lock bits operation (in ms)
20138564acf9Swdenk
20148564acf9Swdenk- CFG_FLASH_PROTECTION
20158564acf9Swdenk		If defined, hardware flash sectors protection is used
20168564acf9Swdenk		instead of U-Boot software protection.
20178564acf9Swdenk
2018c609719bSwdenk- CFG_DIRECT_FLASH_TFTP:
2019c609719bSwdenk
2020c609719bSwdenk		Enable TFTP transfers directly to flash memory;
2021c609719bSwdenk		without this option such a download has to be
2022c609719bSwdenk		performed in two steps: (1) download to RAM, and (2)
2023c609719bSwdenk		copy from RAM to flash.
2024c609719bSwdenk
2025c609719bSwdenk		The two-step approach is usually more reliable, since
2026c609719bSwdenk		you can check if the download worked before you erase
2027c609719bSwdenk		the flash, but in some situations (when sytem RAM is
2028c609719bSwdenk		too limited to allow for a tempory copy of the
2029c609719bSwdenk		downloaded image) this option may be very useful.
2030c609719bSwdenk
2031c609719bSwdenk- CFG_FLASH_CFI:
2032c609719bSwdenk		Define if the flash driver uses extra elements in the
20335653fc33Swdenk		common flash structure for storing flash geometry.
20345653fc33Swdenk
20355653fc33Swdenk- CFG_FLASH_CFI_DRIVER
20365653fc33Swdenk		This option also enables the building of the cfi_flash driver
20375653fc33Swdenk		in the drivers directory
203853cf9435Sstroese
20395568e613SStefan Roese- CFG_FLASH_QUIET_TEST
20405568e613SStefan Roese		If this option is defined, the common CFI flash doesn't
20415568e613SStefan Roese		print it's warning upon not recognized FLASH banks. This
20425568e613SStefan Roese		is useful, if some of the configured banks are only
20435568e613SStefan Roese		optionally available.
20445568e613SStefan Roese
20459a042e9cSJerry Van Baren- CONFIG_FLASH_SHOW_PROGRESS
20469a042e9cSJerry Van Baren		If defined (must be an integer), print out countdown
20479a042e9cSJerry Van Baren		digits and dots.  Recommended value: 45 (9..1) for 80
20489a042e9cSJerry Van Baren		column displays, 15 (3..1) for 40 column displays.
20499a042e9cSJerry Van Baren
205053cf9435Sstroese- CFG_RX_ETH_BUFFER:
205153cf9435Sstroese		Defines the number of ethernet receive buffers. On some
205253cf9435Sstroese		ethernet controllers it is recommended to set this value
205353cf9435Sstroese		to 8 or even higher (EEPRO100 or 405 EMAC), since all
205453cf9435Sstroese		buffers can be full shortly after enabling the interface
205553cf9435Sstroese		on high ethernet traffic.
205653cf9435Sstroese		Defaults to 4 if not defined.
2057c609719bSwdenk
2058c609719bSwdenkThe following definitions that deal with the placement and management
2059c609719bSwdenkof environment data (variable area); in general, we support the
2060c609719bSwdenkfollowing configurations:
2061c609719bSwdenk
2062c609719bSwdenk- CFG_ENV_IS_IN_FLASH:
2063c609719bSwdenk
2064c609719bSwdenk	Define this if the environment is in flash memory.
2065c609719bSwdenk
2066c609719bSwdenk	a) The environment occupies one whole flash sector, which is
2067c609719bSwdenk	   "embedded" in the text segment with the U-Boot code. This
2068c609719bSwdenk	   happens usually with "bottom boot sector" or "top boot
2069c609719bSwdenk	   sector" type flash chips, which have several smaller
2070c609719bSwdenk	   sectors at the start or the end. For instance, such a
2071c609719bSwdenk	   layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2072c609719bSwdenk	   such a case you would place the environment in one of the
2073c609719bSwdenk	   4 kB sectors - with U-Boot code before and after it. With
2074c609719bSwdenk	   "top boot sector" type flash chips, you would put the
2075c609719bSwdenk	   environment in one of the last sectors, leaving a gap
2076c609719bSwdenk	   between U-Boot and the environment.
2077c609719bSwdenk
2078c609719bSwdenk	- CFG_ENV_OFFSET:
2079c609719bSwdenk
2080c609719bSwdenk	   Offset of environment data (variable area) to the
2081c609719bSwdenk	   beginning of flash memory; for instance, with bottom boot
2082c609719bSwdenk	   type flash chips the second sector can be used: the offset
2083c609719bSwdenk	   for this sector is given here.
2084c609719bSwdenk
2085c609719bSwdenk	   CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
2086c609719bSwdenk
2087c609719bSwdenk	- CFG_ENV_ADDR:
2088c609719bSwdenk
2089c609719bSwdenk	   This is just another way to specify the start address of
2090c609719bSwdenk	   the flash sector containing the environment (instead of
2091c609719bSwdenk	   CFG_ENV_OFFSET).
2092c609719bSwdenk
2093c609719bSwdenk	- CFG_ENV_SECT_SIZE:
2094c609719bSwdenk
2095c609719bSwdenk	   Size of the sector containing the environment.
2096c609719bSwdenk
2097c609719bSwdenk
2098c609719bSwdenk	b) Sometimes flash chips have few, equal sized, BIG sectors.
2099c609719bSwdenk	   In such a case you don't want to spend a whole sector for
2100c609719bSwdenk	   the environment.
2101c609719bSwdenk
2102c609719bSwdenk	- CFG_ENV_SIZE:
2103c609719bSwdenk
2104c609719bSwdenk	   If you use this in combination with CFG_ENV_IS_IN_FLASH
2105c609719bSwdenk	   and CFG_ENV_SECT_SIZE, you can specify to use only a part
2106c609719bSwdenk	   of this flash sector for the environment. This saves
2107c609719bSwdenk	   memory for the RAM copy of the environment.
2108c609719bSwdenk
2109c609719bSwdenk	   It may also save flash memory if you decide to use this
2110c609719bSwdenk	   when your environment is "embedded" within U-Boot code,
2111c609719bSwdenk	   since then the remainder of the flash sector could be used
2112c609719bSwdenk	   for U-Boot code. It should be pointed out that this is
2113c609719bSwdenk	   STRONGLY DISCOURAGED from a robustness point of view:
2114c609719bSwdenk	   updating the environment in flash makes it always
2115c609719bSwdenk	   necessary to erase the WHOLE sector. If something goes
2116c609719bSwdenk	   wrong before the contents has been restored from a copy in
2117c609719bSwdenk	   RAM, your target system will be dead.
2118c609719bSwdenk
2119c609719bSwdenk	- CFG_ENV_ADDR_REDUND
2120c609719bSwdenk	  CFG_ENV_SIZE_REDUND
2121c609719bSwdenk
2122c609719bSwdenk	   These settings describe a second storage area used to hold
2123c609719bSwdenk	   a redundand copy of the environment data, so that there is
21243e38691eSwdenk	   a valid backup copy in case there is a power failure during
2125c609719bSwdenk	   a "saveenv" operation.
2126c609719bSwdenk
2127c609719bSwdenkBE CAREFUL! Any changes to the flash layout, and some changes to the
2128c609719bSwdenksource code will make it necessary to adapt <board>/u-boot.lds*
2129c609719bSwdenkaccordingly!
2130c609719bSwdenk
2131c609719bSwdenk
2132c609719bSwdenk- CFG_ENV_IS_IN_NVRAM:
2133c609719bSwdenk
2134c609719bSwdenk	Define this if you have some non-volatile memory device
2135c609719bSwdenk	(NVRAM, battery buffered SRAM) which you want to use for the
2136c609719bSwdenk	environment.
2137c609719bSwdenk
2138c609719bSwdenk	- CFG_ENV_ADDR:
2139c609719bSwdenk	- CFG_ENV_SIZE:
2140c609719bSwdenk
2141c609719bSwdenk	  These two #defines are used to determin the memory area you
2142c609719bSwdenk	  want to use for environment. It is assumed that this memory
2143c609719bSwdenk	  can just be read and written to, without any special
2144c609719bSwdenk	  provision.
2145c609719bSwdenk
2146c609719bSwdenkBE CAREFUL! The first access to the environment happens quite early
2147c609719bSwdenkin U-Boot initalization (when we try to get the setting of for the
2148c609719bSwdenkconsole baudrate). You *MUST* have mappend your NVRAM area then, or
2149c609719bSwdenkU-Boot will hang.
2150c609719bSwdenk
2151c609719bSwdenkPlease note that even with NVRAM we still use a copy of the
2152c609719bSwdenkenvironment in RAM: we could work on NVRAM directly, but we want to
2153c609719bSwdenkkeep settings there always unmodified except somebody uses "saveenv"
2154c609719bSwdenkto save the current settings.
2155c609719bSwdenk
2156c609719bSwdenk
2157c609719bSwdenk- CFG_ENV_IS_IN_EEPROM:
2158c609719bSwdenk
2159c609719bSwdenk	Use this if you have an EEPROM or similar serial access
2160c609719bSwdenk	device and a driver for it.
2161c609719bSwdenk
2162c609719bSwdenk	- CFG_ENV_OFFSET:
2163c609719bSwdenk	- CFG_ENV_SIZE:
2164c609719bSwdenk
2165c609719bSwdenk	  These two #defines specify the offset and size of the
2166c609719bSwdenk	  environment area within the total memory of your EEPROM.
2167c609719bSwdenk
2168c609719bSwdenk	- CFG_I2C_EEPROM_ADDR:
2169c609719bSwdenk	  If defined, specified the chip address of the EEPROM device.
2170c609719bSwdenk	  The default address is zero.
2171c609719bSwdenk
2172c609719bSwdenk	- CFG_EEPROM_PAGE_WRITE_BITS:
2173c609719bSwdenk	  If defined, the number of bits used to address bytes in a
2174c609719bSwdenk	  single page in the EEPROM device.  A 64 byte page, for example
2175c609719bSwdenk	  would require six bits.
2176c609719bSwdenk
2177c609719bSwdenk	- CFG_EEPROM_PAGE_WRITE_DELAY_MS:
2178c609719bSwdenk	  If defined, the number of milliseconds to delay between
2179c609719bSwdenk	  page writes.	The default is zero milliseconds.
2180c609719bSwdenk
2181c609719bSwdenk	- CFG_I2C_EEPROM_ADDR_LEN:
2182c609719bSwdenk	  The length in bytes of the EEPROM memory array address.  Note
2183c609719bSwdenk	  that this is NOT the chip address length!
2184c609719bSwdenk
21855cf91d6bSwdenk	- CFG_I2C_EEPROM_ADDR_OVERFLOW:
21865cf91d6bSwdenk	  EEPROM chips that implement "address overflow" are ones
21875cf91d6bSwdenk	  like Catalyst 24WC04/08/16 which has 9/10/11 bits of
21885cf91d6bSwdenk	  address and the extra bits end up in the "chip address" bit
21895cf91d6bSwdenk	  slots. This makes a 24WC08 (1Kbyte) chip look like four 256
21905cf91d6bSwdenk	  byte chips.
21915cf91d6bSwdenk
21925cf91d6bSwdenk	  Note that we consider the length of the address field to
21935cf91d6bSwdenk	  still be one byte because the extra address bits are hidden
21945cf91d6bSwdenk	  in the chip address.
21955cf91d6bSwdenk
2196c609719bSwdenk	- CFG_EEPROM_SIZE:
2197c609719bSwdenk	  The size in bytes of the EEPROM device.
2198c609719bSwdenk
2199c609719bSwdenk
22005779d8d9Swdenk- CFG_ENV_IS_IN_DATAFLASH:
22015779d8d9Swdenk
22025779d8d9Swdenk	Define this if you have a DataFlash memory device which you
22035779d8d9Swdenk	want to use for the environment.
22045779d8d9Swdenk
22055779d8d9Swdenk	- CFG_ENV_OFFSET:
22065779d8d9Swdenk	- CFG_ENV_ADDR:
22075779d8d9Swdenk	- CFG_ENV_SIZE:
22085779d8d9Swdenk
22095779d8d9Swdenk	  These three #defines specify the offset and size of the
22105779d8d9Swdenk	  environment area within the total memory of your DataFlash placed
22115779d8d9Swdenk	  at the specified address.
22125779d8d9Swdenk
221313a5695bSwdenk- CFG_ENV_IS_IN_NAND:
221413a5695bSwdenk
221513a5695bSwdenk	Define this if you have a NAND device which you want to use
221613a5695bSwdenk	for the environment.
221713a5695bSwdenk
221813a5695bSwdenk	- CFG_ENV_OFFSET:
221913a5695bSwdenk	- CFG_ENV_SIZE:
222013a5695bSwdenk
222113a5695bSwdenk	  These two #defines specify the offset and size of the environment
222213a5695bSwdenk	  area within the first NAND device.
22235779d8d9Swdenk
2224e443c944SMarkus Klotzbuecher	- CFG_ENV_OFFSET_REDUND
2225e443c944SMarkus Klotzbuecher
2226e443c944SMarkus Klotzbuecher	  This setting describes a second storage area of CFG_ENV_SIZE
2227e443c944SMarkus Klotzbuecher	  size used to hold a redundant copy of the environment data,
2228e443c944SMarkus Klotzbuecher	  so that there is a valid backup copy in case there is a
2229e443c944SMarkus Klotzbuecher	  power failure during a "saveenv" operation.
2230e443c944SMarkus Klotzbuecher
2231e443c944SMarkus Klotzbuecher	Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned
2232e443c944SMarkus Klotzbuecher	to a block boundary, and CFG_ENV_SIZE must be a multiple of
2233e443c944SMarkus Klotzbuecher	the NAND devices block size.
2234e443c944SMarkus Klotzbuecher
2235c609719bSwdenk- CFG_SPI_INIT_OFFSET
2236c609719bSwdenk
2237c609719bSwdenk	Defines offset to the initial SPI buffer area in DPRAM. The
2238c609719bSwdenk	area is used at an early stage (ROM part) if the environment
2239c609719bSwdenk	is configured to reside in the SPI EEPROM: We need a 520 byte
2240c609719bSwdenk	scratch DPRAM area. It is used between the two initialization
2241c609719bSwdenk	calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2242c609719bSwdenk	to be a good choice since it makes it far enough from the
2243c609719bSwdenk	start of the data area as well as from the stack pointer.
2244c609719bSwdenk
2245e881cb56SBruce AdlerPlease note that the environment is read-only until the monitor
2246c609719bSwdenkhas been relocated to RAM and a RAM copy of the environment has been
2247c609719bSwdenkcreated; also, when using EEPROM you will have to use getenv_r()
2248c609719bSwdenkuntil then to read environment variables.
2249c609719bSwdenk
225085ec0bccSwdenkThe environment is protected by a CRC32 checksum. Before the monitor
225185ec0bccSwdenkis relocated into RAM, as a result of a bad CRC you will be working
225285ec0bccSwdenkwith the compiled-in default environment - *silently*!!! [This is
225385ec0bccSwdenknecessary, because the first environment variable we need is the
225485ec0bccSwdenk"baudrate" setting for the console - if we have a bad CRC, we don't
225585ec0bccSwdenkhave any device yet where we could complain.]
2256c609719bSwdenk
2257c609719bSwdenkNote: once the monitor has been relocated, then it will complain if
2258c609719bSwdenkthe default environment is used; a new CRC is computed as soon as you
225985ec0bccSwdenkuse the "saveenv" command to store a valid environment.
2260c609719bSwdenk
2261fc3e2165Swdenk- CFG_FAULT_ECHO_LINK_DOWN:
2262fc3e2165Swdenk		Echo the inverted Ethernet link state to the fault LED.
2263fc3e2165Swdenk
2264fc3e2165Swdenk		Note: If this option is active, then CFG_FAULT_MII_ADDR
2265fc3e2165Swdenk		      also needs to be defined.
2266fc3e2165Swdenk
2267fc3e2165Swdenk- CFG_FAULT_MII_ADDR:
2268fc3e2165Swdenk		MII address of the PHY to check for the Ethernet link state.
2269c609719bSwdenk
2270c40b2956Swdenk- CFG_64BIT_VSPRINTF:
2271c40b2956Swdenk		Makes vsprintf (and all *printf functions) support printing
2272c40b2956Swdenk		of 64bit values by using the L quantifier
2273c40b2956Swdenk
2274c40b2956Swdenk- CFG_64BIT_STRTOUL:
2275c40b2956Swdenk		Adds simple_strtoull that returns a 64bit value
2276c40b2956Swdenk
2277c609719bSwdenkLow Level (hardware related) configuration options:
2278dc7c9a1aSwdenk---------------------------------------------------
2279c609719bSwdenk
2280c609719bSwdenk- CFG_CACHELINE_SIZE:
2281c609719bSwdenk		Cache Line Size of the CPU.
2282c609719bSwdenk
2283c609719bSwdenk- CFG_DEFAULT_IMMR:
2284c609719bSwdenk		Default address of the IMMR after system reset.
22852535d602Swdenk
22862535d602Swdenk		Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
22872535d602Swdenk		and RPXsuper) to be able to adjust the position of
22882535d602Swdenk		the IMMR register after a reset.
2289c609719bSwdenk
22907f6c2cbcSwdenk- Floppy Disk Support:
22917f6c2cbcSwdenk		CFG_FDC_DRIVE_NUMBER
22927f6c2cbcSwdenk
22937f6c2cbcSwdenk		the default drive number (default value 0)
22947f6c2cbcSwdenk
22957f6c2cbcSwdenk		CFG_ISA_IO_STRIDE
22967f6c2cbcSwdenk
22977f6c2cbcSwdenk		defines the spacing between fdc chipset registers
22987f6c2cbcSwdenk		(default value 1)
22997f6c2cbcSwdenk
23007f6c2cbcSwdenk		CFG_ISA_IO_OFFSET
23017f6c2cbcSwdenk
23027f6c2cbcSwdenk		defines the offset of register from address. It
23037f6c2cbcSwdenk		depends on which part of the data bus is connected to
23047f6c2cbcSwdenk		the fdc chipset. (default value 0)
23057f6c2cbcSwdenk
23067f6c2cbcSwdenk		If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
23077f6c2cbcSwdenk		CFG_FDC_DRIVE_NUMBER are undefined, they take their
23087f6c2cbcSwdenk		default value.
23097f6c2cbcSwdenk
23107f6c2cbcSwdenk		if CFG_FDC_HW_INIT is defined, then the function
23117f6c2cbcSwdenk		fdc_hw_init() is called at the beginning of the FDC
23127f6c2cbcSwdenk		setup. fdc_hw_init() must be provided by the board
23137f6c2cbcSwdenk		source code. It is used to make hardware dependant
23147f6c2cbcSwdenk		initializations.
23157f6c2cbcSwdenk
231625d6712aSwdenk- CFG_IMMR:	Physical address of the Internal Memory.
231725d6712aSwdenk		DO NOT CHANGE unless you know exactly what you're
231825d6712aSwdenk		doing! (11-4) [MPC8xx/82xx systems only]
2319c609719bSwdenk
2320c609719bSwdenk- CFG_INIT_RAM_ADDR:
2321c609719bSwdenk
23227152b1d0Swdenk		Start address of memory area that can be used for
2323c609719bSwdenk		initial data and stack; please note that this must be
2324c609719bSwdenk		writable memory that is working WITHOUT special
2325c609719bSwdenk		initialization, i. e. you CANNOT use normal RAM which
2326c609719bSwdenk		will become available only after programming the
2327c609719bSwdenk		memory controller and running certain initialization
2328c609719bSwdenk		sequences.
2329c609719bSwdenk
2330c609719bSwdenk		U-Boot uses the following memory types:
2331c609719bSwdenk		- MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2332c609719bSwdenk		- MPC824X: data cache
2333c609719bSwdenk		- PPC4xx:  data cache
2334c609719bSwdenk
233585ec0bccSwdenk- CFG_GBL_DATA_OFFSET:
2336c609719bSwdenk
2337c609719bSwdenk		Offset of the initial data structure in the memory
2338c609719bSwdenk		area defined by CFG_INIT_RAM_ADDR. Usually
233985ec0bccSwdenk		CFG_GBL_DATA_OFFSET is chosen such that the initial
2340c609719bSwdenk		data is located at the end of the available space
2341c609719bSwdenk		(sometimes written as (CFG_INIT_RAM_END -
2342c609719bSwdenk		CFG_INIT_DATA_SIZE), and the initial stack is just
2343c609719bSwdenk		below that area (growing from (CFG_INIT_RAM_ADDR +
234485ec0bccSwdenk		CFG_GBL_DATA_OFFSET) downward.
2345c609719bSwdenk
2346c609719bSwdenk	Note:
2347c609719bSwdenk		On the MPC824X (or other systems that use the data
2348c609719bSwdenk		cache for initial memory) the address chosen for
2349c609719bSwdenk		CFG_INIT_RAM_ADDR is basically arbitrary - it must
2350c609719bSwdenk		point to an otherwise UNUSED address space between
2351c609719bSwdenk		the top of RAM and the start of the PCI space.
2352c609719bSwdenk
2353c609719bSwdenk- CFG_SIUMCR:	SIU Module Configuration (11-6)
2354c609719bSwdenk
2355c609719bSwdenk- CFG_SYPCR:	System Protection Control (11-9)
2356c609719bSwdenk
2357c609719bSwdenk- CFG_TBSCR:	Time Base Status and Control (11-26)
2358c609719bSwdenk
2359c609719bSwdenk- CFG_PISCR:	Periodic Interrupt Status and Control (11-31)
2360c609719bSwdenk
2361c609719bSwdenk- CFG_PLPRCR:	PLL, Low-Power, and Reset Control Register (15-30)
2362c609719bSwdenk
2363c609719bSwdenk- CFG_SCCR:	System Clock and reset Control Register (15-27)
2364c609719bSwdenk
2365c609719bSwdenk- CFG_OR_TIMING_SDRAM:
2366c609719bSwdenk		SDRAM timing
2367c609719bSwdenk
2368c609719bSwdenk- CFG_MAMR_PTA:
2369c609719bSwdenk		periodic timer for refresh
2370c609719bSwdenk
2371c609719bSwdenk- CFG_DER:	Debug Event Register (37-47)
2372c609719bSwdenk
2373c609719bSwdenk- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2374c609719bSwdenk  CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2375c609719bSwdenk  CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2376c609719bSwdenk  CFG_BR1_PRELIM:
2377c609719bSwdenk		Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2378c609719bSwdenk
2379c609719bSwdenk- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2380c609719bSwdenk  CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2381c609719bSwdenk  CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2382c609719bSwdenk		Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2383c609719bSwdenk
2384c609719bSwdenk- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2385c609719bSwdenk  CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2386c609719bSwdenk		Machine Mode Register and Memory Periodic Timer
2387c609719bSwdenk		Prescaler definitions (SDRAM timing)
2388c609719bSwdenk
2389c609719bSwdenk- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2390c609719bSwdenk		enable I2C microcode relocation patch (MPC8xx);
2391c609719bSwdenk		define relocation offset in DPRAM [DSP2]
2392c609719bSwdenk
2393b423d055SHeiko Schocher- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]:
2394b423d055SHeiko Schocher		enable SMC microcode relocation patch (MPC8xx);
2395b423d055SHeiko Schocher		define relocation offset in DPRAM [SMC1]
2396b423d055SHeiko Schocher
2397c609719bSwdenk- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2398c609719bSwdenk		enable SPI microcode relocation patch (MPC8xx);
2399c609719bSwdenk		define relocation offset in DPRAM [SCC4]
2400c609719bSwdenk
2401c609719bSwdenk- CFG_USE_OSCCLK:
2402c609719bSwdenk		Use OSCM clock mode on MBX8xx board. Be careful,
2403c609719bSwdenk		wrong setting might damage your board. Read
2404c609719bSwdenk		doc/README.MBX before setting this variable!
2405c609719bSwdenk
2406ea909b76Swdenk- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2407ea909b76Swdenk		Offset of the bootmode word in DPRAM used by post
2408ea909b76Swdenk		(Power On Self Tests). This definition overrides
2409ea909b76Swdenk		#define'd default value in commproc.h resp.
2410ea909b76Swdenk		cpm_8260.h.
2411ea909b76Swdenk
24125d232d0eSwdenk- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
24135d232d0eSwdenk  CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
24145d232d0eSwdenk  CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
24155d232d0eSwdenk  CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
24165d232d0eSwdenk  CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
24175d232d0eSwdenk  CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
24185d232d0eSwdenk  CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
24195d232d0eSwdenk  CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
24205d232d0eSwdenk		Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
24215d232d0eSwdenk
2422bb99ad6dSBen Warren- CONFIG_SPD_EEPROM
2423218ca724SWolfgang Denk		Get DDR timing information from an I2C EEPROM. Common
2424218ca724SWolfgang Denk		with pluggable memory modules such as SODIMMs
2425218ca724SWolfgang Denk
2426bb99ad6dSBen Warren  SPD_EEPROM_ADDRESS
2427bb99ad6dSBen Warren		I2C address of the SPD EEPROM
2428bb99ad6dSBen Warren
2429bb99ad6dSBen Warren- CFG_SPD_BUS_NUM
2430218ca724SWolfgang Denk		If SPD EEPROM is on an I2C bus other than the first
2431218ca724SWolfgang Denk		one, specify here. Note that the value must resolve
2432218ca724SWolfgang Denk		to something your driver can deal with.
2433bb99ad6dSBen Warren
24342ad6b513STimur Tabi- CFG_83XX_DDR_USES_CS0
2435218ca724SWolfgang Denk		Only for 83xx systems. If specified, then DDR should
2436218ca724SWolfgang Denk		be configured using CS0 and CS1 instead of CS2 and CS3.
24372ad6b513STimur Tabi
24382ad6b513STimur Tabi- CFG_83XX_DDR_USES_CS0
2439218ca724SWolfgang Denk		Only for 83xx systems. If specified, then DDR should
2440218ca724SWolfgang Denk		be configured using CS0 and CS1 instead of CS2 and CS3.
24412ad6b513STimur Tabi
2442c26e454dSwdenk- CONFIG_ETHER_ON_FEC[12]
2443c26e454dSwdenk		Define to enable FEC[12] on a 8xx series processor.
2444c26e454dSwdenk
2445c26e454dSwdenk- CONFIG_FEC[12]_PHY
2446c26e454dSwdenk		Define to the hardcoded PHY address which corresponds
24476e592385Swdenk		to the given FEC; i. e.
2448c26e454dSwdenk			#define CONFIG_FEC1_PHY 4
2449c26e454dSwdenk		means that the PHY with address 4 is connected to FEC1
2450c26e454dSwdenk
2451c26e454dSwdenk		When set to -1, means to probe for first available.
2452c26e454dSwdenk
2453c26e454dSwdenk- CONFIG_FEC[12]_PHY_NORXERR
2454c26e454dSwdenk		The PHY does not have a RXERR line (RMII only).
2455c26e454dSwdenk		(so program the FEC to ignore it).
2456c26e454dSwdenk
2457c26e454dSwdenk- CONFIG_RMII
2458c26e454dSwdenk		Enable RMII mode for all FECs.
2459c26e454dSwdenk		Note that this is a global option, we can't
2460c26e454dSwdenk		have one FEC in standard MII mode and another in RMII mode.
2461c26e454dSwdenk
24625cf91d6bSwdenk- CONFIG_CRC32_VERIFY
24635cf91d6bSwdenk		Add a verify option to the crc32 command.
24645cf91d6bSwdenk		The syntax is:
24655cf91d6bSwdenk
24665cf91d6bSwdenk		=> crc32 -v <address> <count> <crc32>
24675cf91d6bSwdenk
24685cf91d6bSwdenk		Where address/count indicate a memory area
24695cf91d6bSwdenk		and crc32 is the correct crc32 which the
24705cf91d6bSwdenk		area should have.
24715cf91d6bSwdenk
247256523f12Swdenk- CONFIG_LOOPW
247356523f12Swdenk		Add the "loopw" memory command. This only takes effect if
2474602ad3b3SJon Loeliger		the memory commands are activated globally (CONFIG_CMD_MEM).
247556523f12Swdenk
24767b466641Sstroese- CONFIG_MX_CYCLIC
24777b466641Sstroese		Add the "mdc" and "mwc" memory commands. These are cyclic
24787b466641Sstroese		"md/mw" commands.
24797b466641Sstroese		Examples:
24807b466641Sstroese
24817b466641Sstroese		=> mdc.b 10 4 500
24827b466641Sstroese		This command will print 4 bytes (10,11,12,13) each 500 ms.
24837b466641Sstroese
24847b466641Sstroese		=> mwc.l 100 12345678 10
24857b466641Sstroese		This command will write 12345678 to address 100 all 10 ms.
24867b466641Sstroese
24877b466641Sstroese		This only takes effect if the memory commands are activated
2488602ad3b3SJon Loeliger		globally (CONFIG_CMD_MEM).
24897b466641Sstroese
24908aa1a2d1Swdenk- CONFIG_SKIP_LOWLEVEL_INIT
24918aa1a2d1Swdenk- CONFIG_SKIP_RELOCATE_UBOOT
24928aa1a2d1Swdenk
24938aa1a2d1Swdenk		[ARM only] If these variables are defined, then
24948aa1a2d1Swdenk		certain low level initializations (like setting up
24958aa1a2d1Swdenk		the memory controller) are omitted and/or U-Boot does
24968aa1a2d1Swdenk		not relocate itself into RAM.
24978aa1a2d1Swdenk		Normally these variables MUST NOT be defined. The
24988aa1a2d1Swdenk		only exception is when U-Boot is loaded (to RAM) by
24998aa1a2d1Swdenk		some other boot loader or by a debugger which
25008aa1a2d1Swdenk		performs these intializations itself.
25018aa1a2d1Swdenk
2502400558b5Swdenk
2503c609719bSwdenkBuilding the Software:
2504c609719bSwdenk======================
2505c609719bSwdenk
2506218ca724SWolfgang DenkBuilding U-Boot has been tested in several native build environments
2507218ca724SWolfgang Denkand in many different cross environments. Of course we cannot support
2508218ca724SWolfgang Denkall possibly existing versions of cross development tools in all
2509218ca724SWolfgang Denk(potentially obsolete) versions. In case of tool chain problems we
2510218ca724SWolfgang Denkrecommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
2511218ca724SWolfgang Denkwhich is extensively used to build and test U-Boot.
2512c609719bSwdenk
2513218ca724SWolfgang DenkIf you are not using a native environment, it is assumed that you
2514218ca724SWolfgang Denkhave GNU cross compiling tools available in your path. In this case,
2515218ca724SWolfgang Denkyou must set the environment variable CROSS_COMPILE in your shell.
2516218ca724SWolfgang DenkNote that no changes to the Makefile or any other source files are
2517218ca724SWolfgang Denknecessary. For example using the ELDK on a 4xx CPU, please enter:
2518c609719bSwdenk
2519218ca724SWolfgang Denk	$ CROSS_COMPILE=ppc_4xx-
2520218ca724SWolfgang Denk	$ export CROSS_COMPILE
2521c609719bSwdenk
2522c609719bSwdenkU-Boot is intended to be simple to build. After installing the
2523c609719bSwdenksources you must configure U-Boot for one specific board type. This
2524c609719bSwdenkis done by typing:
2525c609719bSwdenk
2526c609719bSwdenk	make NAME_config
2527c609719bSwdenk
2528218ca724SWolfgang Denkwhere "NAME_config" is the name of one of the existing configu-
2529218ca724SWolfgang Denkrations; see the main Makefile for supported names.
253054387ac9Swdenk
2531c609719bSwdenkNote: for some board special configuration names may exist; check if
2532c609719bSwdenk      additional information is available from the board vendor; for
25332729af9dSwdenk      instance, the TQM823L systems are available without (standard)
25342729af9dSwdenk      or with LCD support. You can select such additional "features"
2535c609719bSwdenk      when chosing the configuration, i. e.
2536c609719bSwdenk
25372729af9dSwdenk      make TQM823L_config
25382729af9dSwdenk	- will configure for a plain TQM823L, i. e. no LCD support
2539c609719bSwdenk
2540c609719bSwdenk      make TQM823L_LCD_config
2541c609719bSwdenk	- will configure for a TQM823L with U-Boot console on LCD
2542c609719bSwdenk
2543c609719bSwdenk      etc.
2544c609719bSwdenk
2545c609719bSwdenk
2546c609719bSwdenkFinally, type "make all", and you should get some working U-Boot
25477152b1d0Swdenkimages ready for download to / installation on your system:
2548c609719bSwdenk
2549c609719bSwdenk- "u-boot.bin" is a raw binary image
2550c609719bSwdenk- "u-boot" is an image in ELF binary format
2551c609719bSwdenk- "u-boot.srec" is in Motorola S-Record format
2552c609719bSwdenk
2553baf31249SMarian BalakowiczBy default the build is performed locally and the objects are saved
2554baf31249SMarian Balakowiczin the source directory. One of the two methods can be used to change
2555baf31249SMarian Balakowiczthis behavior and build U-Boot to some external directory:
2556baf31249SMarian Balakowicz
2557baf31249SMarian Balakowicz1. Add O= to the make command line invocations:
2558baf31249SMarian Balakowicz
2559baf31249SMarian Balakowicz	make O=/tmp/build distclean
2560baf31249SMarian Balakowicz	make O=/tmp/build NAME_config
2561baf31249SMarian Balakowicz	make O=/tmp/build all
2562baf31249SMarian Balakowicz
2563baf31249SMarian Balakowicz2. Set environment variable BUILD_DIR to point to the desired location:
2564baf31249SMarian Balakowicz
2565baf31249SMarian Balakowicz	export BUILD_DIR=/tmp/build
2566baf31249SMarian Balakowicz	make distclean
2567baf31249SMarian Balakowicz	make NAME_config
2568baf31249SMarian Balakowicz	make all
2569baf31249SMarian Balakowicz
2570baf31249SMarian BalakowiczNote that the command line "O=" setting overrides the BUILD_DIR environment
2571baf31249SMarian Balakowiczvariable.
2572baf31249SMarian Balakowicz
2573c609719bSwdenk
2574c609719bSwdenkPlease be aware that the Makefiles assume you are using GNU make, so
2575c609719bSwdenkfor instance on NetBSD you might need to use "gmake" instead of
2576c609719bSwdenknative "make".
2577c609719bSwdenk
2578c609719bSwdenk
2579c609719bSwdenkIf the system board that you have is not listed, then you will need
2580c609719bSwdenkto port U-Boot to your hardware platform. To do this, follow these
2581c609719bSwdenksteps:
2582c609719bSwdenk
2583c609719bSwdenk1.  Add a new configuration option for your board to the toplevel
258485ec0bccSwdenk    "Makefile" and to the "MAKEALL" script, using the existing
258585ec0bccSwdenk    entries as examples. Note that here and at many other places
25867152b1d0Swdenk    boards and other names are listed in alphabetical sort order. Please
258785ec0bccSwdenk    keep this order.
2588c609719bSwdenk2.  Create a new directory to hold your board specific code. Add any
258985ec0bccSwdenk    files you need. In your board directory, you will need at least
259085ec0bccSwdenk    the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
259185ec0bccSwdenk3.  Create a new configuration file "include/configs/<board>.h" for
259285ec0bccSwdenk    your board
2593c609719bSwdenk3.  If you're porting U-Boot to a new CPU, then also create a new
2594c609719bSwdenk    directory to hold your CPU specific code. Add any files you need.
259585ec0bccSwdenk4.  Run "make <board>_config" with your new name.
2596c609719bSwdenk5.  Type "make", and you should get a working "u-boot.srec" file
2597c609719bSwdenk    to be installed on your target system.
259885ec0bccSwdenk6.  Debug and solve any problems that might arise.
2599c609719bSwdenk    [Of course, this last step is much harder than it sounds.]
2600c609719bSwdenk
2601c609719bSwdenk
2602c609719bSwdenkTesting of U-Boot Modifications, Ports to New Hardware, etc.:
2603c609719bSwdenk==============================================================
2604c609719bSwdenk
2605c609719bSwdenkIf you have modified U-Boot sources (for instance added a new board
2606c609719bSwdenkor support for new devices, a new CPU, etc.) you are expected to
2607c609719bSwdenkprovide feedback to the other developers. The feedback normally takes
2608c609719bSwdenkthe form of a "patch", i. e. a context diff against a certain (latest
2609218ca724SWolfgang Denkofficial or latest in the git repository) version of U-Boot sources.
2610c609719bSwdenk
2611c609719bSwdenkBut before you submit such a patch, please verify that your modifi-
2612c609719bSwdenkcation did not break existing code. At least make sure that *ALL* of
2613c609719bSwdenkthe supported boards compile WITHOUT ANY compiler warnings. To do so,
2614c609719bSwdenkjust run the "MAKEALL" script, which will configure and build U-Boot
2615c609719bSwdenkfor ALL supported system. Be warned, this will take a while. You can
26167152b1d0Swdenkselect which (cross) compiler to use by passing a `CROSS_COMPILE'
2617218ca724SWolfgang Denkenvironment variable to the script, i. e. to use the ELDK cross tools
2618218ca724SWolfgang Denkyou can type
2619c609719bSwdenk
2620c609719bSwdenk	CROSS_COMPILE=ppc_8xx- MAKEALL
2621c609719bSwdenk
2622c609719bSwdenkor to build on a native PowerPC system you can type
2623c609719bSwdenk
2624c609719bSwdenk	CROSS_COMPILE=' ' MAKEALL
2625c609719bSwdenk
2626218ca724SWolfgang DenkWhen using the MAKEALL script, the default behaviour is to build
2627218ca724SWolfgang DenkU-Boot in the source directory. This location can be changed by
2628218ca724SWolfgang Denksetting the BUILD_DIR environment variable. Also, for each target
2629218ca724SWolfgang Denkbuilt, the MAKEALL script saves two log files (<target>.ERR and
2630218ca724SWolfgang Denk<target>.MAKEALL) in the <source dir>/LOG directory. This default
2631218ca724SWolfgang Denklocation can be changed by setting the MAKEALL_LOGDIR environment
2632218ca724SWolfgang Denkvariable. For example:
2633baf31249SMarian Balakowicz
2634baf31249SMarian Balakowicz	export BUILD_DIR=/tmp/build
2635baf31249SMarian Balakowicz	export MAKEALL_LOGDIR=/tmp/log
2636baf31249SMarian Balakowicz	CROSS_COMPILE=ppc_8xx- MAKEALL
2637baf31249SMarian Balakowicz
2638218ca724SWolfgang DenkWith the above settings build objects are saved in the /tmp/build,
2639218ca724SWolfgang Denklog files are saved in the /tmp/log and the source tree remains clean
2640218ca724SWolfgang Denkduring the whole build process.
2641baf31249SMarian Balakowicz
2642baf31249SMarian Balakowicz
2643c609719bSwdenkSee also "U-Boot Porting Guide" below.
2644c609719bSwdenk
2645c609719bSwdenk
2646c609719bSwdenkMonitor Commands - Overview:
2647c609719bSwdenk============================
2648c609719bSwdenk
2649c609719bSwdenkgo	- start application at address 'addr'
2650c609719bSwdenkrun	- run commands in an environment variable
2651c609719bSwdenkbootm	- boot application image from memory
2652c609719bSwdenkbootp	- boot image via network using BootP/TFTP protocol
2653c609719bSwdenktftpboot- boot image via network using TFTP protocol
2654c609719bSwdenk	       and env variables "ipaddr" and "serverip"
2655c609719bSwdenk	       (and eventually "gatewayip")
2656c609719bSwdenkrarpboot- boot image via network using RARP/TFTP protocol
2657c609719bSwdenkdiskboot- boot from IDE devicebootd   - boot default, i.e., run 'bootcmd'
2658c609719bSwdenkloads	- load S-Record file over serial line
2659c609719bSwdenkloadb	- load binary file over serial line (kermit mode)
2660c609719bSwdenkmd	- memory display
2661c609719bSwdenkmm	- memory modify (auto-incrementing)
2662c609719bSwdenknm	- memory modify (constant address)
2663c609719bSwdenkmw	- memory write (fill)
2664c609719bSwdenkcp	- memory copy
2665c609719bSwdenkcmp	- memory compare
2666c609719bSwdenkcrc32	- checksum calculation
2667c609719bSwdenkimd	- i2c memory display
2668c609719bSwdenkimm	- i2c memory modify (auto-incrementing)
2669c609719bSwdenkinm	- i2c memory modify (constant address)
2670c609719bSwdenkimw	- i2c memory write (fill)
2671c609719bSwdenkicrc32	- i2c checksum calculation
2672c609719bSwdenkiprobe	- probe to discover valid I2C chip addresses
2673c609719bSwdenkiloop	- infinite loop on address range
2674c609719bSwdenkisdram	- print SDRAM configuration information
2675c609719bSwdenksspi	- SPI utility commands
2676c609719bSwdenkbase	- print or set address offset
2677c609719bSwdenkprintenv- print environment variables
2678c609719bSwdenksetenv	- set environment variables
2679c609719bSwdenksaveenv - save environment variables to persistent storage
2680c609719bSwdenkprotect - enable or disable FLASH write protection
2681c609719bSwdenkerase	- erase FLASH memory
2682c609719bSwdenkflinfo	- print FLASH memory information
2683c609719bSwdenkbdinfo	- print Board Info structure
2684c609719bSwdenkiminfo	- print header information for application image
2685c609719bSwdenkconinfo - print console devices and informations
2686c609719bSwdenkide	- IDE sub-system
2687c609719bSwdenkloop	- infinite loop on address range
268856523f12Swdenkloopw	- infinite write loop on address range
2689c609719bSwdenkmtest	- simple RAM test
2690c609719bSwdenkicache	- enable or disable instruction cache
2691c609719bSwdenkdcache	- enable or disable data cache
2692c609719bSwdenkreset	- Perform RESET of the CPU
2693c609719bSwdenkecho	- echo args to console
2694c609719bSwdenkversion - print monitor version
2695c609719bSwdenkhelp	- print online help
2696c609719bSwdenk?	- alias for 'help'
2697c609719bSwdenk
2698c609719bSwdenk
2699c609719bSwdenkMonitor Commands - Detailed Description:
2700c609719bSwdenk========================================
2701c609719bSwdenk
2702c609719bSwdenkTODO.
2703c609719bSwdenk
2704c609719bSwdenkFor now: just type "help <command>".
2705c609719bSwdenk
2706c609719bSwdenk
2707c609719bSwdenkEnvironment Variables:
2708c609719bSwdenk======================
2709c609719bSwdenk
2710c609719bSwdenkU-Boot supports user configuration using Environment Variables which
2711c609719bSwdenkcan be made persistent by saving to Flash memory.
2712c609719bSwdenk
2713c609719bSwdenkEnvironment Variables are set using "setenv", printed using
2714c609719bSwdenk"printenv", and saved to Flash using "saveenv". Using "setenv"
2715c609719bSwdenkwithout a value can be used to delete a variable from the
2716c609719bSwdenkenvironment. As long as you don't save the environment you are
2717c609719bSwdenkworking with an in-memory copy. In case the Flash area containing the
2718c609719bSwdenkenvironment is erased by accident, a default environment is provided.
2719c609719bSwdenk
2720c609719bSwdenkSome configuration options can be set using Environment Variables:
2721c609719bSwdenk
2722c609719bSwdenk  baudrate	- see CONFIG_BAUDRATE
2723c609719bSwdenk
2724c609719bSwdenk  bootdelay	- see CONFIG_BOOTDELAY
2725c609719bSwdenk
2726c609719bSwdenk  bootcmd	- see CONFIG_BOOTCOMMAND
2727c609719bSwdenk
2728c609719bSwdenk  bootargs	- Boot arguments when booting an RTOS image
2729c609719bSwdenk
2730c609719bSwdenk  bootfile	- Name of the image to load with TFTP
2731c609719bSwdenk
2732c609719bSwdenk  autoload	- if set to "no" (any string beginning with 'n'),
2733c609719bSwdenk		  "bootp" will just load perform a lookup of the
2734c609719bSwdenk		  configuration from the BOOTP server, but not try to
2735c609719bSwdenk		  load any image using TFTP
2736c609719bSwdenk
27373310c549SMarian Balakowicz  autoscript	- if set to "yes" commands like "loadb", "loady",
27383310c549SMarian Balakowicz		  "bootp", "tftpb", "rarpboot" and "nfs" will attempt
27393310c549SMarian Balakowicz		  to automatically run script images (by internally
27403310c549SMarian Balakowicz		  calling "autoscript").
27413310c549SMarian Balakowicz
27423310c549SMarian Balakowicz  autoscript_uname - if script image is in a format (FIT) this
27433310c549SMarian Balakowicz		     variable is used to get script subimage unit name.
27443310c549SMarian Balakowicz
2745c609719bSwdenk  autostart	- if set to "yes", an image loaded using the "bootp",
2746c609719bSwdenk		  "rarpboot", "tftpboot" or "diskboot" commands will
2747c609719bSwdenk		  be automatically started (by internally calling
2748c609719bSwdenk		  "bootm")
2749c609719bSwdenk
27504a6fd34bSwdenk		  If set to "no", a standalone image passed to the
27514a6fd34bSwdenk		  "bootm" command will be copied to the load address
27524a6fd34bSwdenk		  (and eventually uncompressed), but NOT be started.
27534a6fd34bSwdenk		  This can be used to load and uncompress arbitrary
27544a6fd34bSwdenk		  data.
27554a6fd34bSwdenk
275617ea1177Swdenk  i2cfast	- (PPC405GP|PPC405EP only)
275717ea1177Swdenk		  if set to 'y' configures Linux I2C driver for fast
275817ea1177Swdenk		  mode (400kHZ). This environment variable is used in
275917ea1177Swdenk		  initialization code. So, for changes to be effective
276017ea1177Swdenk		  it must be saved and board must be reset.
276117ea1177Swdenk
2762c609719bSwdenk  initrd_high	- restrict positioning of initrd images:
2763c609719bSwdenk		  If this variable is not set, initrd images will be
2764c609719bSwdenk		  copied to the highest possible address in RAM; this
2765c609719bSwdenk		  is usually what you want since it allows for
2766c609719bSwdenk		  maximum initrd size. If for some reason you want to
2767c609719bSwdenk		  make sure that the initrd image is loaded below the
2768c609719bSwdenk		  CFG_BOOTMAPSZ limit, you can set this environment
2769c609719bSwdenk		  variable to a value of "no" or "off" or "0".
2770c609719bSwdenk		  Alternatively, you can set it to a maximum upper
2771c609719bSwdenk		  address to use (U-Boot will still check that it
2772c609719bSwdenk		  does not overwrite the U-Boot stack and data).
2773c609719bSwdenk
2774c609719bSwdenk		  For instance, when you have a system with 16 MB
27757152b1d0Swdenk		  RAM, and want to reserve 4 MB from use by Linux,
2776c609719bSwdenk		  you can do this by adding "mem=12M" to the value of
2777c609719bSwdenk		  the "bootargs" variable. However, now you must make
27787152b1d0Swdenk		  sure that the initrd image is placed in the first
2779c609719bSwdenk		  12 MB as well - this can be done with
2780c609719bSwdenk
2781c609719bSwdenk		  setenv initrd_high 00c00000
2782c609719bSwdenk
278338b99261Swdenk		  If you set initrd_high to 0xFFFFFFFF, this is an
278438b99261Swdenk		  indication to U-Boot that all addresses are legal
278538b99261Swdenk		  for the Linux kernel, including addresses in flash
278638b99261Swdenk		  memory. In this case U-Boot will NOT COPY the
278738b99261Swdenk		  ramdisk at all. This may be useful to reduce the
278838b99261Swdenk		  boot time on your system, but requires that this
278938b99261Swdenk		  feature is supported by your Linux kernel.
279038b99261Swdenk
2791c609719bSwdenk  ipaddr	- IP address; needed for tftpboot command
2792c609719bSwdenk
2793c609719bSwdenk  loadaddr	- Default load address for commands like "bootp",
2794dc7c9a1aSwdenk		  "rarpboot", "tftpboot", "loadb" or "diskboot"
2795c609719bSwdenk
2796c609719bSwdenk  loads_echo	- see CONFIG_LOADS_ECHO
2797c609719bSwdenk
2798c609719bSwdenk  serverip	- TFTP server IP address; needed for tftpboot command
2799c609719bSwdenk
2800c609719bSwdenk  bootretry	- see CONFIG_BOOT_RETRY_TIME
2801c609719bSwdenk
2802c609719bSwdenk  bootdelaykey	- see CONFIG_AUTOBOOT_DELAY_STR
2803c609719bSwdenk
2804c609719bSwdenk  bootstopkey	- see CONFIG_AUTOBOOT_STOP_STR
2805c609719bSwdenk
2806a3d991bdSwdenk  ethprime	- When CONFIG_NET_MULTI is enabled controls which
2807a3d991bdSwdenk		  interface is used first.
2808a3d991bdSwdenk
2809a3d991bdSwdenk  ethact	- When CONFIG_NET_MULTI is enabled controls which
2810a3d991bdSwdenk		  interface is currently active. For example you
2811a3d991bdSwdenk		  can do the following
2812a3d991bdSwdenk
2813a3d991bdSwdenk		  => setenv ethact FEC ETHERNET
2814a3d991bdSwdenk		  => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2815a3d991bdSwdenk		  => setenv ethact SCC ETHERNET
2816a3d991bdSwdenk		  => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2817a3d991bdSwdenk
2818e1692577SMatthias Fuchs  ethrotate	- When set to "no" U-Boot does not go through all
2819e1692577SMatthias Fuchs		  available network interfaces.
2820e1692577SMatthias Fuchs		  It just stays at the currently selected interface.
2821e1692577SMatthias Fuchs
2822a3d991bdSwdenk   netretry	- When set to "no" each network operation will
2823a3d991bdSwdenk		  either succeed or fail without retrying.
28246e592385Swdenk		  When set to "once" the network operation will
28256e592385Swdenk		  fail when all the available network interfaces
28266e592385Swdenk		  are tried once without success.
2827a3d991bdSwdenk		  Useful on scripts which control the retry operation
2828a3d991bdSwdenk		  themselves.
2829a3d991bdSwdenk
2830a1cf027aSJean-Christophe PLAGNIOL-VILLARD  npe_ucode	- see CONFIG_IXP4XX_NPE_EXT_UCOD
2831a1cf027aSJean-Christophe PLAGNIOL-VILLARD		  if set load address for the npe microcode
2832a1cf027aSJean-Christophe PLAGNIOL-VILLARD
283328cb9375SWolfgang Denk  tftpsrcport	- If this is set, the value is used for TFTP's
2834ecb0ccd9SWolfgang Denk		  UDP source port.
2835ecb0ccd9SWolfgang Denk
283628cb9375SWolfgang Denk  tftpdstport	- If this is set, the value is used for TFTP's UDP
283728cb9375SWolfgang Denk		  destination port instead of the Well Know Port 69.
283828cb9375SWolfgang Denk
2839a3d991bdSwdenk   vlan		- When set to a value < 4095 the traffic over
2840a3d991bdSwdenk		  ethernet is encapsulated/received over 802.1q
2841a3d991bdSwdenk		  VLAN tagged frames.
2842c609719bSwdenk
2843c609719bSwdenkThe following environment variables may be used and automatically
2844c609719bSwdenkupdated by the network boot commands ("bootp" and "rarpboot"),
2845c609719bSwdenkdepending the information provided by your boot server:
2846c609719bSwdenk
2847c609719bSwdenk  bootfile	- see above
2848c609719bSwdenk  dnsip		- IP address of your Domain Name Server
2849fe389a82Sstroese  dnsip2	- IP address of your secondary Domain Name Server
2850c609719bSwdenk  gatewayip	- IP address of the Gateway (Router) to use
2851c609719bSwdenk  hostname	- Target hostname
2852c609719bSwdenk  ipaddr	- see above
2853c609719bSwdenk  netmask	- Subnet Mask
2854c609719bSwdenk  rootpath	- Pathname of the root filesystem on the NFS server
2855c609719bSwdenk  serverip	- see above
2856c609719bSwdenk
2857c609719bSwdenk
2858c609719bSwdenkThere are two special Environment Variables:
2859c609719bSwdenk
2860c609719bSwdenk  serial#	- contains hardware identification information such
2861c609719bSwdenk		  as type string and/or serial number
2862c609719bSwdenk  ethaddr	- Ethernet address
2863c609719bSwdenk
2864c609719bSwdenkThese variables can be set only once (usually during manufacturing of
2865c609719bSwdenkthe board). U-Boot refuses to delete or overwrite these variables
2866c609719bSwdenkonce they have been set once.
2867c609719bSwdenk
2868c609719bSwdenk
2869c1551ea8SstroeseFurther special Environment Variables:
2870c1551ea8Sstroese
2871c1551ea8Sstroese  ver		- Contains the U-Boot version string as printed
2872c1551ea8Sstroese		  with the "version" command. This variable is
2873c1551ea8Sstroese		  readonly (see CONFIG_VERSION_VARIABLE).
2874c1551ea8Sstroese
2875c1551ea8Sstroese
2876c609719bSwdenkPlease note that changes to some configuration parameters may take
2877c609719bSwdenkonly effect after the next boot (yes, that's just like Windoze :-).
2878c609719bSwdenk
2879c609719bSwdenk
2880f07771ccSwdenkCommand Line Parsing:
2881f07771ccSwdenk=====================
2882f07771ccSwdenk
2883f07771ccSwdenkThere are two different command line parsers available with U-Boot:
28847152b1d0Swdenkthe old "simple" one, and the much more powerful "hush" shell:
2885f07771ccSwdenk
2886f07771ccSwdenkOld, simple command line parser:
2887f07771ccSwdenk--------------------------------
2888f07771ccSwdenk
2889f07771ccSwdenk- supports environment variables (through setenv / saveenv commands)
2890f07771ccSwdenk- several commands on one line, separated by ';'
2891fe126d8bSWolfgang Denk- variable substitution using "... ${name} ..." syntax
2892f07771ccSwdenk- special characters ('$', ';') can be escaped by prefixing with '\',
2893f07771ccSwdenk  for example:
2894fe126d8bSWolfgang Denk	setenv bootcmd bootm \${address}
2895f07771ccSwdenk- You can also escape text by enclosing in single apostrophes, for example:
2896f07771ccSwdenk	setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2897f07771ccSwdenk
2898f07771ccSwdenkHush shell:
2899f07771ccSwdenk-----------
2900f07771ccSwdenk
2901f07771ccSwdenk- similar to Bourne shell, with control structures like
2902f07771ccSwdenk  if...then...else...fi, for...do...done; while...do...done,
2903f07771ccSwdenk  until...do...done, ...
2904f07771ccSwdenk- supports environment ("global") variables (through setenv / saveenv
2905f07771ccSwdenk  commands) and local shell variables (through standard shell syntax
2906f07771ccSwdenk  "name=value"); only environment variables can be used with "run"
2907f07771ccSwdenk  command
2908f07771ccSwdenk
2909f07771ccSwdenkGeneral rules:
2910f07771ccSwdenk--------------
2911f07771ccSwdenk
2912f07771ccSwdenk(1) If a command line (or an environment variable executed by a "run"
2913f07771ccSwdenk    command) contains several commands separated by semicolon, and
2914f07771ccSwdenk    one of these commands fails, then the remaining commands will be
2915f07771ccSwdenk    executed anyway.
2916f07771ccSwdenk
2917f07771ccSwdenk(2) If you execute several variables with one call to run (i. e.
2918f07771ccSwdenk    calling run with a list af variables as arguments), any failing
2919f07771ccSwdenk    command will cause "run" to terminate, i. e. the remaining
2920f07771ccSwdenk    variables are not executed.
2921f07771ccSwdenk
2922c609719bSwdenkNote for Redundant Ethernet Interfaces:
2923c609719bSwdenk=======================================
2924c609719bSwdenk
29257152b1d0SwdenkSome boards come with redundant ethernet interfaces; U-Boot supports
2926c609719bSwdenksuch configurations and is capable of automatic selection of a
29277152b1d0Swdenk"working" interface when needed. MAC assignment works as follows:
2928c609719bSwdenk
2929c609719bSwdenkNetwork interfaces are numbered eth0, eth1, eth2, ... Corresponding
2930c609719bSwdenkMAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2931c609719bSwdenk"eth1addr" (=>eth1), "eth2addr", ...
2932c609719bSwdenk
2933c609719bSwdenkIf the network interface stores some valid MAC address (for instance
2934c609719bSwdenkin SROM), this is used as default address if there is NO correspon-
2935c609719bSwdenkding setting in the environment; if the corresponding environment
2936c609719bSwdenkvariable is set, this overrides the settings in the card; that means:
2937c609719bSwdenk
2938c609719bSwdenko If the SROM has a valid MAC address, and there is no address in the
2939c609719bSwdenk  environment, the SROM's address is used.
2940c609719bSwdenk
2941c609719bSwdenko If there is no valid address in the SROM, and a definition in the
2942c609719bSwdenk  environment exists, then the value from the environment variable is
2943c609719bSwdenk  used.
2944c609719bSwdenk
2945c609719bSwdenko If both the SROM and the environment contain a MAC address, and
2946c609719bSwdenk  both addresses are the same, this MAC address is used.
2947c609719bSwdenk
2948c609719bSwdenko If both the SROM and the environment contain a MAC address, and the
2949c609719bSwdenk  addresses differ, the value from the environment is used and a
2950c609719bSwdenk  warning is printed.
2951c609719bSwdenk
2952c609719bSwdenko If neither SROM nor the environment contain a MAC address, an error
2953c609719bSwdenk  is raised.
2954c609719bSwdenk
2955c609719bSwdenk
2956c609719bSwdenkImage Formats:
2957c609719bSwdenk==============
2958c609719bSwdenk
29593310c549SMarian BalakowiczU-Boot is capable of booting (and performing other auxiliary operations on)
29603310c549SMarian Balakowiczimages in two formats:
29613310c549SMarian Balakowicz
29623310c549SMarian BalakowiczNew uImage format (FIT)
29633310c549SMarian Balakowicz-----------------------
29643310c549SMarian Balakowicz
29653310c549SMarian BalakowiczFlexible and powerful format based on Flattened Image Tree -- FIT (similar
29663310c549SMarian Balakowiczto Flattened Device Tree). It allows the use of images with multiple
29673310c549SMarian Balakowiczcomponents (several kernels, ramdisks, etc.), with contents protected by
29683310c549SMarian BalakowiczSHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
29693310c549SMarian Balakowicz
29703310c549SMarian Balakowicz
29713310c549SMarian BalakowiczOld uImage format
29723310c549SMarian Balakowicz-----------------
29733310c549SMarian Balakowicz
29743310c549SMarian BalakowiczOld image format is based on binary files which can be basically anything,
29753310c549SMarian Balakowiczpreceded by a special header; see the definitions in include/image.h for
29763310c549SMarian Balakowiczdetails; basically, the header defines the following image properties:
2977c609719bSwdenk
2978c609719bSwdenk* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2979c609719bSwdenk  4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
29807f70e853Swdenk  LynxOS, pSOS, QNX, RTEMS, ARTOS;
29811f4bb37dSwdenk  Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
29827b64fef3SWolfgang Denk* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
29833d1e8a9dSwdenk  IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
29847b64fef3SWolfgang Denk  Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
2985c29fdfc1Swdenk* Compression Type (uncompressed, gzip, bzip2)
2986c609719bSwdenk* Load Address
2987c609719bSwdenk* Entry Point
2988c609719bSwdenk* Image Name
2989c609719bSwdenk* Image Timestamp
2990c609719bSwdenk
2991c609719bSwdenkThe header is marked by a special Magic Number, and both the header
2992c609719bSwdenkand the data portions of the image are secured against corruption by
2993c609719bSwdenkCRC32 checksums.
2994c609719bSwdenk
2995c609719bSwdenk
2996c609719bSwdenkLinux Support:
2997c609719bSwdenk==============
2998c609719bSwdenk
2999c609719bSwdenkAlthough U-Boot should support any OS or standalone application
30007152b1d0Swdenkeasily, the main focus has always been on Linux during the design of
3001c609719bSwdenkU-Boot.
3002c609719bSwdenk
3003c609719bSwdenkU-Boot includes many features that so far have been part of some
3004c609719bSwdenkspecial "boot loader" code within the Linux kernel. Also, any
3005c609719bSwdenk"initrd" images to be used are no longer part of one big Linux image;
3006c609719bSwdenkinstead, kernel and "initrd" are separate images. This implementation
30077152b1d0Swdenkserves several purposes:
3008c609719bSwdenk
3009c609719bSwdenk- the same features can be used for other OS or standalone
3010c609719bSwdenk  applications (for instance: using compressed images to reduce the
3011c609719bSwdenk  Flash memory footprint)
3012c609719bSwdenk
3013c609719bSwdenk- it becomes much easier to port new Linux kernel versions because
30147152b1d0Swdenk  lots of low-level, hardware dependent stuff are done by U-Boot
3015c609719bSwdenk
3016c609719bSwdenk- the same Linux kernel image can now be used with different "initrd"
3017c609719bSwdenk  images; of course this also means that different kernel images can
3018c609719bSwdenk  be run with the same "initrd". This makes testing easier (you don't
3019c609719bSwdenk  have to build a new "zImage.initrd" Linux image when you just
3020c609719bSwdenk  change a file in your "initrd"). Also, a field-upgrade of the
3021c609719bSwdenk  software is easier now.
3022c609719bSwdenk
3023c609719bSwdenk
3024c609719bSwdenkLinux HOWTO:
3025c609719bSwdenk============
3026c609719bSwdenk
3027c609719bSwdenkPorting Linux to U-Boot based systems:
3028c609719bSwdenk---------------------------------------
3029c609719bSwdenk
3030c609719bSwdenkU-Boot cannot save you from doing all the necessary modifications to
3031c609719bSwdenkconfigure the Linux device drivers for use with your target hardware
3032c609719bSwdenk(no, we don't intend to provide a full virtual machine interface to
3033c609719bSwdenkLinux :-).
3034c609719bSwdenk
3035c609719bSwdenkBut now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
3036c609719bSwdenk
3037c609719bSwdenkJust make sure your machine specific header file (for instance
3038c609719bSwdenkinclude/asm-ppc/tqm8xx.h) includes the same definition of the Board
3039c609719bSwdenkInformation structure as we define in include/u-boot.h, and make
3040c609719bSwdenksure that your definition of IMAP_ADDR uses the same value as your
3041c609719bSwdenkU-Boot configuration in CFG_IMMR.
3042c609719bSwdenk
3043c609719bSwdenk
3044c609719bSwdenkConfiguring the Linux kernel:
3045c609719bSwdenk-----------------------------
3046c609719bSwdenk
3047c609719bSwdenkNo specific requirements for U-Boot. Make sure you have some root
3048c609719bSwdenkdevice (initial ramdisk, NFS) for your target system.
3049c609719bSwdenk
3050c609719bSwdenk
3051c609719bSwdenkBuilding a Linux Image:
3052c609719bSwdenk-----------------------
3053c609719bSwdenk
305424ee89b9SwdenkWith U-Boot, "normal" build targets like "zImage" or "bzImage" are
305524ee89b9Swdenknot used. If you use recent kernel source, a new build target
305624ee89b9Swdenk"uImage" will exist which automatically builds an image usable by
305724ee89b9SwdenkU-Boot. Most older kernels also have support for a "pImage" target,
305824ee89b9Swdenkwhich was introduced for our predecessor project PPCBoot and uses a
305924ee89b9Swdenk100% compatible format.
3060c609719bSwdenk
3061c609719bSwdenkExample:
3062c609719bSwdenk
3063c609719bSwdenk	make TQM850L_config
3064c609719bSwdenk	make oldconfig
3065c609719bSwdenk	make dep
306624ee89b9Swdenk	make uImage
3067c609719bSwdenk
306824ee89b9SwdenkThe "uImage" build target uses a special tool (in 'tools/mkimage') to
306924ee89b9Swdenkencapsulate a compressed Linux kernel image with header	 information,
307024ee89b9SwdenkCRC32 checksum etc. for use with U-Boot. This is what we are doing:
3071c609719bSwdenk
307224ee89b9Swdenk* build a standard "vmlinux" kernel image (in ELF binary format):
307324ee89b9Swdenk
307424ee89b9Swdenk* convert the kernel into a raw binary image:
307524ee89b9Swdenk
307624ee89b9Swdenk	${CROSS_COMPILE}-objcopy -O binary \
307724ee89b9Swdenk				 -R .note -R .comment \
307824ee89b9Swdenk				 -S vmlinux linux.bin
307924ee89b9Swdenk
308024ee89b9Swdenk* compress the binary image:
308124ee89b9Swdenk
308224ee89b9Swdenk	gzip -9 linux.bin
308324ee89b9Swdenk
308424ee89b9Swdenk* package compressed binary image for U-Boot:
308524ee89b9Swdenk
308624ee89b9Swdenk	mkimage -A ppc -O linux -T kernel -C gzip \
308724ee89b9Swdenk		-a 0 -e 0 -n "Linux Kernel Image" \
308824ee89b9Swdenk		-d linux.bin.gz uImage
308924ee89b9Swdenk
309024ee89b9Swdenk
309124ee89b9SwdenkThe "mkimage" tool can also be used to create ramdisk images for use
309224ee89b9Swdenkwith U-Boot, either separated from the Linux kernel image, or
309324ee89b9Swdenkcombined into one file. "mkimage" encapsulates the images with a 64
309424ee89b9Swdenkbyte header containing information about target architecture,
309524ee89b9Swdenkoperating system, image type, compression method, entry points, time
309624ee89b9Swdenkstamp, CRC32 checksums, etc.
309724ee89b9Swdenk
309824ee89b9Swdenk"mkimage" can be called in two ways: to verify existing images and
309924ee89b9Swdenkprint the header information, or to build new images.
3100c609719bSwdenk
3101c609719bSwdenkIn the first form (with "-l" option) mkimage lists the information
3102c609719bSwdenkcontained in the header of an existing U-Boot image; this includes
3103c609719bSwdenkchecksum verification:
3104c609719bSwdenk
3105c609719bSwdenk	tools/mkimage -l image
3106c609719bSwdenk	  -l ==> list image header information
3107c609719bSwdenk
3108c609719bSwdenkThe second form (with "-d" option) is used to build a U-Boot image
3109c609719bSwdenkfrom a "data file" which is used as image payload:
3110c609719bSwdenk
3111c609719bSwdenk	tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3112c609719bSwdenk		      -n name -d data_file image
3113c609719bSwdenk	  -A ==> set architecture to 'arch'
3114c609719bSwdenk	  -O ==> set operating system to 'os'
3115c609719bSwdenk	  -T ==> set image type to 'type'
3116c609719bSwdenk	  -C ==> set compression type 'comp'
3117c609719bSwdenk	  -a ==> set load address to 'addr' (hex)
3118c609719bSwdenk	  -e ==> set entry point to 'ep' (hex)
3119c609719bSwdenk	  -n ==> set image name to 'name'
3120c609719bSwdenk	  -d ==> use image data from 'datafile'
3121c609719bSwdenk
312269459791SwdenkRight now, all Linux kernels for PowerPC systems use the same load
312369459791Swdenkaddress (0x00000000), but the entry point address depends on the
312469459791Swdenkkernel version:
3125c609719bSwdenk
3126c609719bSwdenk- 2.2.x kernels have the entry point at 0x0000000C,
312724ee89b9Swdenk- 2.3.x and later kernels have the entry point at 0x00000000.
3128c609719bSwdenk
3129c609719bSwdenkSo a typical call to build a U-Boot image would read:
3130c609719bSwdenk
313124ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
313224ee89b9Swdenk	> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
313324ee89b9Swdenk	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
313424ee89b9Swdenk	> examples/uImage.TQM850L
313524ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
3136c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
3137c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
3138c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
3139c609719bSwdenk	Load Address: 0x00000000
314024ee89b9Swdenk	Entry Point:  0x00000000
3141c609719bSwdenk
3142c609719bSwdenkTo verify the contents of the image (or check for corruption):
3143c609719bSwdenk
314424ee89b9Swdenk	-> tools/mkimage -l examples/uImage.TQM850L
314524ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
3146c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
3147c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (gzip compressed)
3148c609719bSwdenk	Data Size:    335725 Bytes = 327.86 kB = 0.32 MB
3149c609719bSwdenk	Load Address: 0x00000000
315024ee89b9Swdenk	Entry Point:  0x00000000
3151c609719bSwdenk
3152c609719bSwdenkNOTE: for embedded systems where boot time is critical you can trade
3153c609719bSwdenkspeed for memory and install an UNCOMPRESSED image instead: this
3154c609719bSwdenkneeds more space in Flash, but boots much faster since it does not
3155c609719bSwdenkneed to be uncompressed:
3156c609719bSwdenk
315724ee89b9Swdenk	-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
315824ee89b9Swdenk	-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
315924ee89b9Swdenk	> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
316024ee89b9Swdenk	> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
316124ee89b9Swdenk	> examples/uImage.TQM850L-uncompressed
316224ee89b9Swdenk	Image Name:   2.4.4 kernel for TQM850L
3163c609719bSwdenk	Created:      Wed Jul 19 02:34:59 2000
3164c609719bSwdenk	Image Type:   PowerPC Linux Kernel Image (uncompressed)
3165c609719bSwdenk	Data Size:    792160 Bytes = 773.59 kB = 0.76 MB
3166c609719bSwdenk	Load Address: 0x00000000
316724ee89b9Swdenk	Entry Point:  0x00000000
3168c609719bSwdenk
3169c609719bSwdenk
3170c609719bSwdenkSimilar you can build U-Boot images from a 'ramdisk.image.gz' file
3171c609719bSwdenkwhen your kernel is intended to use an initial ramdisk:
3172c609719bSwdenk
3173c609719bSwdenk	-> tools/mkimage -n 'Simple Ramdisk Image' \
3174c609719bSwdenk	> -A ppc -O linux -T ramdisk -C gzip \
3175c609719bSwdenk	> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3176c609719bSwdenk	Image Name:   Simple Ramdisk Image
3177c609719bSwdenk	Created:      Wed Jan 12 14:01:50 2000
3178c609719bSwdenk	Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
3179c609719bSwdenk	Data Size:    566530 Bytes = 553.25 kB = 0.54 MB
3180c609719bSwdenk	Load Address: 0x00000000
3181c609719bSwdenk	Entry Point:  0x00000000
3182c609719bSwdenk
3183c609719bSwdenk
3184c609719bSwdenkInstalling a Linux Image:
3185c609719bSwdenk-------------------------
3186c609719bSwdenk
3187c609719bSwdenkTo downloading a U-Boot image over the serial (console) interface,
3188c609719bSwdenkyou must convert the image to S-Record format:
3189c609719bSwdenk
3190c609719bSwdenk	objcopy -I binary -O srec examples/image examples/image.srec
3191c609719bSwdenk
3192c609719bSwdenkThe 'objcopy' does not understand the information in the U-Boot
3193c609719bSwdenkimage header, so the resulting S-Record file will be relative to
3194c609719bSwdenkaddress 0x00000000. To load it to a given address, you need to
3195c609719bSwdenkspecify the target address as 'offset' parameter with the 'loads'
3196c609719bSwdenkcommand.
3197c609719bSwdenk
3198c609719bSwdenkExample: install the image to address 0x40100000 (which on the
3199c609719bSwdenkTQM8xxL is in the first Flash bank):
3200c609719bSwdenk
3201c609719bSwdenk	=> erase 40100000 401FFFFF
3202c609719bSwdenk
3203c609719bSwdenk	.......... done
3204c609719bSwdenk	Erased 8 sectors
3205c609719bSwdenk
3206c609719bSwdenk	=> loads 40100000
3207c609719bSwdenk	## Ready for S-Record download ...
3208c609719bSwdenk	~>examples/image.srec
3209c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3210c609719bSwdenk	...
3211c609719bSwdenk	15989 15990 15991 15992
3212c609719bSwdenk	[file transfer complete]
3213c609719bSwdenk	[connected]
3214c609719bSwdenk	## Start Addr = 0x00000000
3215c609719bSwdenk
3216c609719bSwdenk
3217c609719bSwdenkYou can check the success of the download using the 'iminfo' command;
3218c609719bSwdenkthis includes a checksum verification so you can be sure no data
3219c609719bSwdenkcorruption happened:
3220c609719bSwdenk
3221c609719bSwdenk	=> imi 40100000
3222c609719bSwdenk
3223c609719bSwdenk	## Checking Image at 40100000 ...
3224c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
3225c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
3226c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
3227c609719bSwdenk	   Load Address: 00000000
3228c609719bSwdenk	   Entry Point:	 0000000c
3229c609719bSwdenk	   Verifying Checksum ... OK
3230c609719bSwdenk
3231c609719bSwdenk
3232c609719bSwdenkBoot Linux:
3233c609719bSwdenk-----------
3234c609719bSwdenk
3235c609719bSwdenkThe "bootm" command is used to boot an application that is stored in
3236c609719bSwdenkmemory (RAM or Flash). In case of a Linux kernel image, the contents
3237c609719bSwdenkof the "bootargs" environment variable is passed to the kernel as
3238c609719bSwdenkparameters. You can check and modify this variable using the
3239c609719bSwdenk"printenv" and "setenv" commands:
3240c609719bSwdenk
3241c609719bSwdenk
3242c609719bSwdenk	=> printenv bootargs
3243c609719bSwdenk	bootargs=root=/dev/ram
3244c609719bSwdenk
3245c609719bSwdenk	=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3246c609719bSwdenk
3247c609719bSwdenk	=> printenv bootargs
3248c609719bSwdenk	bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3249c609719bSwdenk
3250c609719bSwdenk	=> bootm 40020000
3251c609719bSwdenk	## Booting Linux kernel at 40020000 ...
3252c609719bSwdenk	   Image Name:	 2.2.13 for NFS on TQM850L
3253c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
3254c609719bSwdenk	   Data Size:	 381681 Bytes = 372 kB = 0 MB
3255c609719bSwdenk	   Load Address: 00000000
3256c609719bSwdenk	   Entry Point:	 0000000c
3257c609719bSwdenk	   Verifying Checksum ... OK
3258c609719bSwdenk	   Uncompressing Kernel Image ... OK
3259c609719bSwdenk	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
3260c609719bSwdenk	Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3261c609719bSwdenk	time_init: decrementer frequency = 187500000/60
3262c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
3263c609719bSwdenk	Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3264c609719bSwdenk	...
3265c609719bSwdenk
3266c609719bSwdenkIf you want to boot a Linux kernel with initial ram disk, you pass
32677152b1d0Swdenkthe memory addresses of both the kernel and the initrd image (PPBCOOT
3268c609719bSwdenkformat!) to the "bootm" command:
3269c609719bSwdenk
3270c609719bSwdenk	=> imi 40100000 40200000
3271c609719bSwdenk
3272c609719bSwdenk	## Checking Image at 40100000 ...
3273c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
3274c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
3275c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
3276c609719bSwdenk	   Load Address: 00000000
3277c609719bSwdenk	   Entry Point:	 0000000c
3278c609719bSwdenk	   Verifying Checksum ... OK
3279c609719bSwdenk
3280c609719bSwdenk	## Checking Image at 40200000 ...
3281c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
3282c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
3283c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
3284c609719bSwdenk	   Load Address: 00000000
3285c609719bSwdenk	   Entry Point:	 00000000
3286c609719bSwdenk	   Verifying Checksum ... OK
3287c609719bSwdenk
3288c609719bSwdenk	=> bootm 40100000 40200000
3289c609719bSwdenk	## Booting Linux kernel at 40100000 ...
3290c609719bSwdenk	   Image Name:	 2.2.13 for initrd on TQM850L
3291c609719bSwdenk	   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
3292c609719bSwdenk	   Data Size:	 335725 Bytes = 327 kB = 0 MB
3293c609719bSwdenk	   Load Address: 00000000
3294c609719bSwdenk	   Entry Point:	 0000000c
3295c609719bSwdenk	   Verifying Checksum ... OK
3296c609719bSwdenk	   Uncompressing Kernel Image ... OK
3297c609719bSwdenk	## Loading RAMDisk Image at 40200000 ...
3298c609719bSwdenk	   Image Name:	 Simple Ramdisk Image
3299c609719bSwdenk	   Image Type:	 PowerPC Linux RAMDisk Image (gzip compressed)
3300c609719bSwdenk	   Data Size:	 566530 Bytes = 553 kB = 0 MB
3301c609719bSwdenk	   Load Address: 00000000
3302c609719bSwdenk	   Entry Point:	 00000000
3303c609719bSwdenk	   Verifying Checksum ... OK
3304c609719bSwdenk	   Loading Ramdisk ... OK
3305c609719bSwdenk	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
3306c609719bSwdenk	Boot arguments: root=/dev/ram
3307c609719bSwdenk	time_init: decrementer frequency = 187500000/60
3308c609719bSwdenk	Calibrating delay loop... 49.77 BogoMIPS
3309c609719bSwdenk	...
3310c609719bSwdenk	RAMDISK: Compressed image found at block 0
3311c609719bSwdenk	VFS: Mounted root (ext2 filesystem).
3312c609719bSwdenk
3313c609719bSwdenk	bash#
3314c609719bSwdenk
33150267768eSMatthew McClintockBoot Linux and pass a flat device tree:
33160267768eSMatthew McClintock-----------
33170267768eSMatthew McClintock
33180267768eSMatthew McClintockFirst, U-Boot must be compiled with the appropriate defines. See the section
33190267768eSMatthew McClintocktitled "Linux Kernel Interface" above for a more in depth explanation. The
33200267768eSMatthew McClintockfollowing is an example of how to start a kernel and pass an updated
33210267768eSMatthew McClintockflat device tree:
33220267768eSMatthew McClintock
33230267768eSMatthew McClintock=> print oftaddr
33240267768eSMatthew McClintockoftaddr=0x300000
33250267768eSMatthew McClintock=> print oft
33260267768eSMatthew McClintockoft=oftrees/mpc8540ads.dtb
33270267768eSMatthew McClintock=> tftp $oftaddr $oft
33280267768eSMatthew McClintockSpeed: 1000, full duplex
33290267768eSMatthew McClintockUsing TSEC0 device
33300267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.101
33310267768eSMatthew McClintockFilename 'oftrees/mpc8540ads.dtb'.
33320267768eSMatthew McClintockLoad address: 0x300000
33330267768eSMatthew McClintockLoading: #
33340267768eSMatthew McClintockdone
33350267768eSMatthew McClintockBytes transferred = 4106 (100a hex)
33360267768eSMatthew McClintock=> tftp $loadaddr $bootfile
33370267768eSMatthew McClintockSpeed: 1000, full duplex
33380267768eSMatthew McClintockUsing TSEC0 device
33390267768eSMatthew McClintockTFTP from server 192.168.1.1; our IP address is 192.168.1.2
33400267768eSMatthew McClintockFilename 'uImage'.
33410267768eSMatthew McClintockLoad address: 0x200000
33420267768eSMatthew McClintockLoading:############
33430267768eSMatthew McClintockdone
33440267768eSMatthew McClintockBytes transferred = 1029407 (fb51f hex)
33450267768eSMatthew McClintock=> print loadaddr
33460267768eSMatthew McClintockloadaddr=200000
33470267768eSMatthew McClintock=> print oftaddr
33480267768eSMatthew McClintockoftaddr=0x300000
33490267768eSMatthew McClintock=> bootm $loadaddr - $oftaddr
33500267768eSMatthew McClintock## Booting image at 00200000 ...
33510267768eSMatthew McClintock   Image Name:	 Linux-2.6.17-dirty
33520267768eSMatthew McClintock   Image Type:	 PowerPC Linux Kernel Image (gzip compressed)
33530267768eSMatthew McClintock   Data Size:	 1029343 Bytes = 1005.2 kB
33540267768eSMatthew McClintock   Load Address: 00000000
33550267768eSMatthew McClintock   Entry Point:	 00000000
33560267768eSMatthew McClintock   Verifying Checksum ... OK
33570267768eSMatthew McClintock   Uncompressing Kernel Image ... OK
33580267768eSMatthew McClintockBooting using flat device tree at 0x300000
33590267768eSMatthew McClintockUsing MPC85xx ADS machine description
33600267768eSMatthew McClintockMemory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
33610267768eSMatthew McClintock[snip]
33620267768eSMatthew McClintock
33630267768eSMatthew McClintock
33646069ff26SwdenkMore About U-Boot Image Types:
33656069ff26Swdenk------------------------------
33666069ff26Swdenk
33676069ff26SwdenkU-Boot supports the following image types:
33686069ff26Swdenk
33696069ff26Swdenk   "Standalone Programs" are directly runnable in the environment
33706069ff26Swdenk	provided by U-Boot; it is expected that (if they behave
33716069ff26Swdenk	well) you can continue to work in U-Boot after return from
33726069ff26Swdenk	the Standalone Program.
33736069ff26Swdenk   "OS Kernel Images" are usually images of some Embedded OS which
33746069ff26Swdenk	will take over control completely. Usually these programs
33756069ff26Swdenk	will install their own set of exception handlers, device
33766069ff26Swdenk	drivers, set up the MMU, etc. - this means, that you cannot
33776069ff26Swdenk	expect to re-enter U-Boot except by resetting the CPU.
33786069ff26Swdenk   "RAMDisk Images" are more or less just data blocks, and their
33796069ff26Swdenk	parameters (address, size) are passed to an OS kernel that is
33806069ff26Swdenk	being started.
33816069ff26Swdenk   "Multi-File Images" contain several images, typically an OS
33826069ff26Swdenk	(Linux) kernel image and one or more data images like
33836069ff26Swdenk	RAMDisks. This construct is useful for instance when you want
33846069ff26Swdenk	to boot over the network using BOOTP etc., where the boot
33856069ff26Swdenk	server provides just a single image file, but you want to get
33866069ff26Swdenk	for instance an OS kernel and a RAMDisk image.
33876069ff26Swdenk
33886069ff26Swdenk	"Multi-File Images" start with a list of image sizes, each
33896069ff26Swdenk	image size (in bytes) specified by an "uint32_t" in network
33906069ff26Swdenk	byte order. This list is terminated by an "(uint32_t)0".
33916069ff26Swdenk	Immediately after the terminating 0 follow the images, one by
33926069ff26Swdenk	one, all aligned on "uint32_t" boundaries (size rounded up to
33936069ff26Swdenk	a multiple of 4 bytes).
33946069ff26Swdenk
33956069ff26Swdenk   "Firmware Images" are binary images containing firmware (like
33966069ff26Swdenk	U-Boot or FPGA images) which usually will be programmed to
33976069ff26Swdenk	flash memory.
33986069ff26Swdenk
33996069ff26Swdenk   "Script files" are command sequences that will be executed by
34006069ff26Swdenk	U-Boot's command interpreter; this feature is especially
34016069ff26Swdenk	useful when you configure U-Boot to use a real shell (hush)
34026069ff26Swdenk	as command interpreter.
34036069ff26Swdenk
3404c609719bSwdenk
3405c609719bSwdenkStandalone HOWTO:
3406c609719bSwdenk=================
3407c609719bSwdenk
3408c609719bSwdenkOne of the features of U-Boot is that you can dynamically load and
3409c609719bSwdenkrun "standalone" applications, which can use some resources of
3410c609719bSwdenkU-Boot like console I/O functions or interrupt services.
3411c609719bSwdenk
3412c609719bSwdenkTwo simple examples are included with the sources:
3413c609719bSwdenk
3414c609719bSwdenk"Hello World" Demo:
3415c609719bSwdenk-------------------
3416c609719bSwdenk
3417c609719bSwdenk'examples/hello_world.c' contains a small "Hello World" Demo
3418c609719bSwdenkapplication; it is automatically compiled when you build U-Boot.
3419c609719bSwdenkIt's configured to run at address 0x00040004, so you can play with it
3420c609719bSwdenklike that:
3421c609719bSwdenk
3422c609719bSwdenk	=> loads
3423c609719bSwdenk	## Ready for S-Record download ...
3424c609719bSwdenk	~>examples/hello_world.srec
3425c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
3426c609719bSwdenk	[file transfer complete]
3427c609719bSwdenk	[connected]
3428c609719bSwdenk	## Start Addr = 0x00040004
3429c609719bSwdenk
3430c609719bSwdenk	=> go 40004 Hello World! This is a test.
3431c609719bSwdenk	## Starting application at 0x00040004 ...
3432c609719bSwdenk	Hello World
3433c609719bSwdenk	argc = 7
3434c609719bSwdenk	argv[0] = "40004"
3435c609719bSwdenk	argv[1] = "Hello"
3436c609719bSwdenk	argv[2] = "World!"
3437c609719bSwdenk	argv[3] = "This"
3438c609719bSwdenk	argv[4] = "is"
3439c609719bSwdenk	argv[5] = "a"
3440c609719bSwdenk	argv[6] = "test."
3441c609719bSwdenk	argv[7] = "<NULL>"
3442c609719bSwdenk	Hit any key to exit ...
3443c609719bSwdenk
3444c609719bSwdenk	## Application terminated, rc = 0x0
3445c609719bSwdenk
3446c609719bSwdenkAnother example, which demonstrates how to register a CPM interrupt
3447c609719bSwdenkhandler with the U-Boot code, can be found in 'examples/timer.c'.
3448c609719bSwdenkHere, a CPM timer is set up to generate an interrupt every second.
3449c609719bSwdenkThe interrupt service routine is trivial, just printing a '.'
3450c609719bSwdenkcharacter, but this is just a demo program. The application can be
3451c609719bSwdenkcontrolled by the following keys:
3452c609719bSwdenk
3453c609719bSwdenk	? - print current values og the CPM Timer registers
3454c609719bSwdenk	b - enable interrupts and start timer
3455c609719bSwdenk	e - stop timer and disable interrupts
3456c609719bSwdenk	q - quit application
3457c609719bSwdenk
3458c609719bSwdenk	=> loads
3459c609719bSwdenk	## Ready for S-Record download ...
3460c609719bSwdenk	~>examples/timer.srec
3461c609719bSwdenk	1 2 3 4 5 6 7 8 9 10 11 ...
3462c609719bSwdenk	[file transfer complete]
3463c609719bSwdenk	[connected]
3464c609719bSwdenk	## Start Addr = 0x00040004
3465c609719bSwdenk
3466c609719bSwdenk	=> go 40004
3467c609719bSwdenk	## Starting application at 0x00040004 ...
3468c609719bSwdenk	TIMERS=0xfff00980
3469c609719bSwdenk	Using timer 1
3470c609719bSwdenk	  tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3471c609719bSwdenk
3472c609719bSwdenkHit 'b':
3473c609719bSwdenk	[q, b, e, ?] Set interval 1000000 us
3474c609719bSwdenk	Enabling timer
3475c609719bSwdenkHit '?':
3476c609719bSwdenk	[q, b, e, ?] ........
3477c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3478c609719bSwdenkHit '?':
3479c609719bSwdenk	[q, b, e, ?] .
3480c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3481c609719bSwdenkHit '?':
3482c609719bSwdenk	[q, b, e, ?] .
3483c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3484c609719bSwdenkHit '?':
3485c609719bSwdenk	[q, b, e, ?] .
3486c609719bSwdenk	tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3487c609719bSwdenkHit 'e':
3488c609719bSwdenk	[q, b, e, ?] ...Stopping timer
3489c609719bSwdenkHit 'q':
3490c609719bSwdenk	[q, b, e, ?] ## Application terminated, rc = 0x0
3491c609719bSwdenk
3492c609719bSwdenk
349385ec0bccSwdenkMinicom warning:
349485ec0bccSwdenk================
349585ec0bccSwdenk
34967152b1d0SwdenkOver time, many people have reported problems when trying to use the
349785ec0bccSwdenk"minicom" terminal emulation program for serial download. I (wd)
349885ec0bccSwdenkconsider minicom to be broken, and recommend not to use it. Under
3499f07771ccSwdenkUnix, I recommend to use C-Kermit for general purpose use (and
350085ec0bccSwdenkespecially for kermit binary protocol download ("loadb" command), and
350185ec0bccSwdenkuse "cu" for S-Record download ("loads" command).
350285ec0bccSwdenk
350352f52c14SwdenkNevertheless, if you absolutely want to use it try adding this
350452f52c14Swdenkconfiguration to your "File transfer protocols" section:
350552f52c14Swdenk
350652f52c14Swdenk	   Name	   Program			Name U/D FullScr IO-Red. Multi
350752f52c14Swdenk	X  kermit  /usr/bin/kermit -i -l %l -s	 Y    U	   Y	   N	  N
350852f52c14Swdenk	Y  kermit  /usr/bin/kermit -i -l %l -r	 N    D	   Y	   N	  N
350952f52c14Swdenk
351052f52c14Swdenk
3511c609719bSwdenkNetBSD Notes:
3512c609719bSwdenk=============
3513c609719bSwdenk
3514c609719bSwdenkStarting at version 0.9.2, U-Boot supports NetBSD both as host
3515c609719bSwdenk(build U-Boot) and target system (boots NetBSD/mpc8xx).
3516c609719bSwdenk
3517c609719bSwdenkBuilding requires a cross environment; it is known to work on
3518c609719bSwdenkNetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3519c609719bSwdenkneed gmake since the Makefiles are not compatible with BSD make).
3520c609719bSwdenkNote that the cross-powerpc package does not install include files;
3521c609719bSwdenkattempting to build U-Boot will fail because <machine/ansi.h> is
3522c609719bSwdenkmissing.  This file has to be installed and patched manually:
3523c609719bSwdenk
3524c609719bSwdenk	# cd /usr/pkg/cross/powerpc-netbsd/include
3525c609719bSwdenk	# mkdir powerpc
3526c609719bSwdenk	# ln -s powerpc machine
3527c609719bSwdenk	# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3528c609719bSwdenk	# ${EDIT} powerpc/ansi.h	## must remove __va_list, _BSD_VA_LIST
3529c609719bSwdenk
3530c609719bSwdenkNative builds *don't* work due to incompatibilities between native
3531c609719bSwdenkand U-Boot include files.
3532c609719bSwdenk
3533c609719bSwdenkBooting assumes that (the first part of) the image booted is a
3534c609719bSwdenkstage-2 loader which in turn loads and then invokes the kernel
3535c609719bSwdenkproper. Loader sources will eventually appear in the NetBSD source
3536c609719bSwdenktree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
35372a8af187Swdenkmeantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3538c609719bSwdenk
3539c609719bSwdenk
3540c609719bSwdenkImplementation Internals:
3541c609719bSwdenk=========================
3542c609719bSwdenk
3543c609719bSwdenkThe following is not intended to be a complete description of every
3544c609719bSwdenkimplementation detail. However, it should help to understand the
3545c609719bSwdenkinner workings of U-Boot and make it easier to port it to custom
3546c609719bSwdenkhardware.
3547c609719bSwdenk
3548c609719bSwdenk
3549c609719bSwdenkInitial Stack, Global Data:
3550c609719bSwdenk---------------------------
3551c609719bSwdenk
3552c609719bSwdenkThe implementation of U-Boot is complicated by the fact that U-Boot
3553c609719bSwdenkstarts running out of ROM (flash memory), usually without access to
3554c609719bSwdenksystem RAM (because the memory controller is not initialized yet).
3555c609719bSwdenkThis means that we don't have writable Data or BSS segments, and BSS
3556c609719bSwdenkis not initialized as zero. To be able to get a C environment working
3557c609719bSwdenkat all, we have to allocate at least a minimal stack. Implementation
3558c609719bSwdenkoptions for this are defined and restricted by the CPU used: Some CPU
3559c609719bSwdenkmodels provide on-chip memory (like the IMMR area on MPC8xx and
3560c609719bSwdenkMPC826x processors), on others (parts of) the data cache can be
3561c609719bSwdenklocked as (mis-) used as memory, etc.
3562c609719bSwdenk
35637152b1d0Swdenk	Chris Hallinan posted a good summary of these issues to the
356443d9616cSwdenk	u-boot-users mailing list:
356543d9616cSwdenk
356643d9616cSwdenk	Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
356743d9616cSwdenk	From: "Chris Hallinan" <clh@net1plus.com>
356843d9616cSwdenk	Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
356943d9616cSwdenk	...
357043d9616cSwdenk
357143d9616cSwdenk	Correct me if I'm wrong, folks, but the way I understand it
357243d9616cSwdenk	is this: Using DCACHE as initial RAM for Stack, etc, does not
357343d9616cSwdenk	require any physical RAM backing up the cache. The cleverness
357443d9616cSwdenk	is that the cache is being used as a temporary supply of
357543d9616cSwdenk	necessary storage before the SDRAM controller is setup. It's
357643d9616cSwdenk	beyond the scope of this list to expain the details, but you
357743d9616cSwdenk	can see how this works by studying the cache architecture and
357843d9616cSwdenk	operation in the architecture and processor-specific manuals.
357943d9616cSwdenk
358043d9616cSwdenk	OCM is On Chip Memory, which I believe the 405GP has 4K. It
358143d9616cSwdenk	is another option for the system designer to use as an
358243d9616cSwdenk	initial stack/ram area prior to SDRAM being available. Either
358343d9616cSwdenk	option should work for you. Using CS 4 should be fine if your
358443d9616cSwdenk	board designers haven't used it for something that would
358543d9616cSwdenk	cause you grief during the initial boot! It is frequently not
358643d9616cSwdenk	used.
358743d9616cSwdenk
358843d9616cSwdenk	CFG_INIT_RAM_ADDR should be somewhere that won't interfere
358943d9616cSwdenk	with your processor/board/system design. The default value
359043d9616cSwdenk	you will find in any recent u-boot distribution in
35918a316c9bSStefan Roese	walnut.h should work for you. I'd set it to a value larger
359243d9616cSwdenk	than your SDRAM module. If you have a 64MB SDRAM module, set
359343d9616cSwdenk	it above 400_0000. Just make sure your board has no resources
359443d9616cSwdenk	that are supposed to respond to that address! That code in
359543d9616cSwdenk	start.S has been around a while and should work as is when
359643d9616cSwdenk	you get the config right.
359743d9616cSwdenk
359843d9616cSwdenk	-Chris Hallinan
359943d9616cSwdenk	DS4.COM, Inc.
360043d9616cSwdenk
3601c609719bSwdenkIt is essential to remember this, since it has some impact on the C
3602c609719bSwdenkcode for the initialization procedures:
3603c609719bSwdenk
3604c609719bSwdenk* Initialized global data (data segment) is read-only. Do not attempt
3605c609719bSwdenk  to write it.
3606c609719bSwdenk
3607c609719bSwdenk* Do not use any unitialized global data (or implicitely initialized
3608c609719bSwdenk  as zero data - BSS segment) at all - this is undefined, initiali-
36097152b1d0Swdenk  zation is performed later (when relocating to RAM).
3610c609719bSwdenk
3611c609719bSwdenk* Stack space is very limited. Avoid big data buffers or things like
3612c609719bSwdenk  that.
3613c609719bSwdenk
3614c609719bSwdenkHaving only the stack as writable memory limits means we cannot use
3615c609719bSwdenknormal global data to share information beween the code. But it
3616c609719bSwdenkturned out that the implementation of U-Boot can be greatly
3617c609719bSwdenksimplified by making a global data structure (gd_t) available to all
3618c609719bSwdenkfunctions. We could pass a pointer to this data as argument to _all_
3619c609719bSwdenkfunctions, but this would bloat the code. Instead we use a feature of
3620c609719bSwdenkthe GCC compiler (Global Register Variables) to share the data: we
3621c609719bSwdenkplace a pointer (gd) to the global data into a register which we
3622c609719bSwdenkreserve for this purpose.
3623c609719bSwdenk
36247152b1d0SwdenkWhen choosing a register for such a purpose we are restricted by the
3625c609719bSwdenkrelevant  (E)ABI  specifications for the current architecture, and by
3626c609719bSwdenkGCC's implementation.
3627c609719bSwdenk
3628c609719bSwdenkFor PowerPC, the following registers have specific use:
3629c609719bSwdenk	R1:	stack pointer
3630e7670f6cSWolfgang Denk	R2:	reserved for system use
3631c609719bSwdenk	R3-R4:	parameter passing and return values
3632c609719bSwdenk	R5-R10: parameter passing
3633c609719bSwdenk	R13:	small data area pointer
3634c609719bSwdenk	R30:	GOT pointer
3635c609719bSwdenk	R31:	frame pointer
3636c609719bSwdenk
3637c609719bSwdenk	(U-Boot also uses R14 as internal GOT pointer.)
3638c609719bSwdenk
3639e7670f6cSWolfgang Denk    ==> U-Boot will use R2 to hold a pointer to the global data
3640c609719bSwdenk
3641c609719bSwdenk    Note: on PPC, we could use a static initializer (since the
3642c609719bSwdenk    address of the global data structure is known at compile time),
3643c609719bSwdenk    but it turned out that reserving a register results in somewhat
3644c609719bSwdenk    smaller code - although the code savings are not that big (on
3645c609719bSwdenk    average for all boards 752 bytes for the whole U-Boot image,
3646c609719bSwdenk    624 text + 127 data).
3647c609719bSwdenk
36484c58eb55SMike FrysingerOn Blackfin, the normal C ABI (except for P5) is followed as documented here:
36494c58eb55SMike Frysinger	http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
36504c58eb55SMike Frysinger
36514c58eb55SMike Frysinger    ==> U-Boot will use P5 to hold a pointer to the global data
36524c58eb55SMike Frysinger
3653c609719bSwdenkOn ARM, the following registers are used:
3654c609719bSwdenk
3655c609719bSwdenk	R0:	function argument word/integer result
3656c609719bSwdenk	R1-R3:	function argument word
3657c609719bSwdenk	R9:	GOT pointer
3658c609719bSwdenk	R10:	stack limit (used only if stack checking if enabled)
3659c609719bSwdenk	R11:	argument (frame) pointer
3660c609719bSwdenk	R12:	temporary workspace
3661c609719bSwdenk	R13:	stack pointer
3662c609719bSwdenk	R14:	link register
3663c609719bSwdenk	R15:	program counter
3664c609719bSwdenk
3665c609719bSwdenk    ==> U-Boot will use R8 to hold a pointer to the global data
3666c609719bSwdenk
3667d87080b7SWolfgang DenkNOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
3668d87080b7SWolfgang Denkor current versions of GCC may "optimize" the code too much.
3669c609719bSwdenk
3670c609719bSwdenkMemory Management:
3671c609719bSwdenk------------------
3672c609719bSwdenk
3673c609719bSwdenkU-Boot runs in system state and uses physical addresses, i.e. the
3674c609719bSwdenkMMU is not used either for address mapping nor for memory protection.
3675c609719bSwdenk
3676c609719bSwdenkThe available memory is mapped to fixed addresses using the memory
3677c609719bSwdenkcontroller. In this process, a contiguous block is formed for each
3678c609719bSwdenkmemory type (Flash, SDRAM, SRAM), even when it consists of several
3679c609719bSwdenkphysical memory banks.
3680c609719bSwdenk
3681c609719bSwdenkU-Boot is installed in the first 128 kB of the first Flash bank (on
3682c609719bSwdenkTQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3683c609719bSwdenkbooting and sizing and initializing DRAM, the code relocates itself
3684c609719bSwdenkto the upper end of DRAM. Immediately below the U-Boot code some
3685c609719bSwdenkmemory is reserved for use by malloc() [see CFG_MALLOC_LEN
3686c609719bSwdenkconfiguration setting]. Below that, a structure with global Board
3687c609719bSwdenkInfo data is placed, followed by the stack (growing downward).
3688c609719bSwdenk
3689c609719bSwdenkAdditionally, some exception handler code is copied to the low 8 kB
3690c609719bSwdenkof DRAM (0x00000000 ... 0x00001FFF).
3691c609719bSwdenk
3692c609719bSwdenkSo a typical memory configuration with 16 MB of DRAM could look like
3693c609719bSwdenkthis:
3694c609719bSwdenk
3695c609719bSwdenk	0x0000 0000	Exception Vector code
3696c609719bSwdenk	      :
3697c609719bSwdenk	0x0000 1FFF
3698c609719bSwdenk	0x0000 2000	Free for Application Use
3699c609719bSwdenk	      :
3700c609719bSwdenk	      :
3701c609719bSwdenk
3702c609719bSwdenk	      :
3703c609719bSwdenk	      :
3704c609719bSwdenk	0x00FB FF20	Monitor Stack (Growing downward)
3705c609719bSwdenk	0x00FB FFAC	Board Info Data and permanent copy of global data
3706c609719bSwdenk	0x00FC 0000	Malloc Arena
3707c609719bSwdenk	      :
3708c609719bSwdenk	0x00FD FFFF
3709c609719bSwdenk	0x00FE 0000	RAM Copy of Monitor Code
3710c609719bSwdenk	...		eventually: LCD or video framebuffer
3711c609719bSwdenk	...		eventually: pRAM (Protected RAM - unchanged by reset)
3712c609719bSwdenk	0x00FF FFFF	[End of RAM]
3713c609719bSwdenk
3714c609719bSwdenk
3715c609719bSwdenkSystem Initialization:
3716c609719bSwdenk----------------------
3717c609719bSwdenk
3718c609719bSwdenkIn the reset configuration, U-Boot starts at the reset entry point
3719c609719bSwdenk(on most PowerPC systens at address 0x00000100). Because of the reset
3720c609719bSwdenkconfiguration for CS0# this is a mirror of the onboard Flash memory.
37217152b1d0SwdenkTo be able to re-map memory U-Boot then jumps to its link address.
3722c609719bSwdenkTo be able to implement the initialization code in C, a (small!)
3723c609719bSwdenkinitial stack is set up in the internal Dual Ported RAM (in case CPUs
3724c609719bSwdenkwhich provide such a feature like MPC8xx or MPC8260), or in a locked
3725c609719bSwdenkpart of the data cache. After that, U-Boot initializes the CPU core,
3726c609719bSwdenkthe caches and the SIU.
3727c609719bSwdenk
3728c609719bSwdenkNext, all (potentially) available memory banks are mapped using a
3729c609719bSwdenkpreliminary mapping. For example, we put them on 512 MB boundaries
3730c609719bSwdenk(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3731c609719bSwdenkon 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3732c609719bSwdenkprogrammed for SDRAM access. Using the temporary configuration, a
3733c609719bSwdenksimple memory test is run that determines the size of the SDRAM
3734c609719bSwdenkbanks.
3735c609719bSwdenk
3736c609719bSwdenkWhen there is more than one SDRAM bank, and the banks are of
37377152b1d0Swdenkdifferent size, the largest is mapped first. For equal size, the first
3738c609719bSwdenkbank (CS2#) is mapped first. The first mapping is always for address
3739c609719bSwdenk0x00000000, with any additional banks following immediately to create
3740c609719bSwdenkcontiguous memory starting from 0.
3741c609719bSwdenk
3742c609719bSwdenkThen, the monitor installs itself at the upper end of the SDRAM area
3743c609719bSwdenkand allocates memory for use by malloc() and for the global Board
3744c609719bSwdenkInfo data; also, the exception vector code is copied to the low RAM
3745c609719bSwdenkpages, and the final stack is set up.
3746c609719bSwdenk
3747c609719bSwdenkOnly after this relocation will you have a "normal" C environment;
3748c609719bSwdenkuntil that you are restricted in several ways, mostly because you are
3749c609719bSwdenkrunning from ROM, and because the code will have to be relocated to a
3750c609719bSwdenknew address in RAM.
3751c609719bSwdenk
3752c609719bSwdenk
3753c609719bSwdenkU-Boot Porting Guide:
3754c609719bSwdenk----------------------
3755c609719bSwdenk
3756c609719bSwdenk[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
37576aff3115Swdenklist, October 2002]
3758c609719bSwdenk
3759c609719bSwdenk
3760c609719bSwdenkint main (int argc, char *argv[])
3761c609719bSwdenk{
3762c609719bSwdenk	sighandler_t no_more_time;
3763c609719bSwdenk
3764c609719bSwdenk	signal (SIGALRM, no_more_time);
3765c609719bSwdenk	alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3766c609719bSwdenk
3767c609719bSwdenk	if (available_money > available_manpower) {
3768c609719bSwdenk		pay consultant to port U-Boot;
3769c609719bSwdenk		return 0;
3770c609719bSwdenk	}
3771c609719bSwdenk
3772c609719bSwdenk	Download latest U-Boot source;
3773c609719bSwdenk
37746aff3115Swdenk	Subscribe to u-boot-users mailing list;
37756aff3115Swdenk
3776c609719bSwdenk	if (clueless) {
3777c609719bSwdenk		email ("Hi, I am new to U-Boot, how do I get started?");
3778c609719bSwdenk	}
3779c609719bSwdenk
3780c609719bSwdenk	while (learning) {
3781c609719bSwdenk		Read the README file in the top level directory;
37827cb22f97Swdenk		Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3783c609719bSwdenk		Read the source, Luke;
3784c609719bSwdenk	}
3785c609719bSwdenk
3786c609719bSwdenk	if (available_money > toLocalCurrency ($2500)) {
3787c609719bSwdenk		Buy a BDI2000;
3788c609719bSwdenk	} else {
3789c609719bSwdenk		Add a lot of aggravation and time;
3790c609719bSwdenk	}
3791c609719bSwdenk
3792c609719bSwdenk	Create your own board support subdirectory;
3793c609719bSwdenk
37946aff3115Swdenk	Create your own board config file;
37956aff3115Swdenk
3796c609719bSwdenk	while (!running) {
3797c609719bSwdenk		do {
3798c609719bSwdenk			Add / modify source code;
3799c609719bSwdenk		} until (compiles);
3800c609719bSwdenk		Debug;
3801c609719bSwdenk		if (clueless)
3802c609719bSwdenk			email ("Hi, I am having problems...");
3803c609719bSwdenk	}
3804c609719bSwdenk	Send patch file to Wolfgang;
3805c609719bSwdenk
3806c609719bSwdenk	return 0;
3807c609719bSwdenk}
3808c609719bSwdenk
3809c609719bSwdenkvoid no_more_time (int sig)
3810c609719bSwdenk{
3811c609719bSwdenk      hire_a_guru();
3812c609719bSwdenk}
3813c609719bSwdenk
3814c609719bSwdenk
3815c609719bSwdenkCoding Standards:
3816c609719bSwdenk-----------------
3817c609719bSwdenk
3818c609719bSwdenkAll contributions to U-Boot should conform to the Linux kernel
38192c051651SDetlev Zundelcoding style; see the file "Documentation/CodingStyle" and the script
38202c051651SDetlev Zundel"scripts/Lindent" in your Linux kernel source directory.  In sources
38212c051651SDetlev Zundeloriginating from U-Boot a style corresponding to "Lindent -pcs" (adding
38222c051651SDetlev Zundelspaces before parameters to function calls) is actually used.
3823c609719bSwdenk
38242c051651SDetlev ZundelSource files originating from a different project (for example the
38252c051651SDetlev ZundelMTD subsystem) are generally exempt from these guidelines and are not
38262c051651SDetlev Zundelreformated to ease subsequent migration to newer versions of those
38272c051651SDetlev Zundelsources.
38282c051651SDetlev Zundel
38292c051651SDetlev ZundelPlease note that U-Boot is implemented in C (and to some small parts in
38302c051651SDetlev ZundelAssembler); no C++ is used, so please do not use C++ style comments (//)
38312c051651SDetlev Zundelin your code.
3832c609719bSwdenk
3833c178d3daSwdenkPlease also stick to the following formatting rules:
3834180d3f74Swdenk- remove any trailing white space
3835180d3f74Swdenk- use TAB characters for indentation, not spaces
3836180d3f74Swdenk- make sure NOT to use DOS '\r\n' line feeds
3837180d3f74Swdenk- do not add more than 2 empty lines to source files
3838180d3f74Swdenk- do not add trailing empty lines to source files
3839180d3f74Swdenk
3840c609719bSwdenkSubmissions which do not conform to the standards may be returned
3841c609719bSwdenkwith a request to reformat the changes.
3842c609719bSwdenk
3843c609719bSwdenk
3844c609719bSwdenkSubmitting Patches:
3845c609719bSwdenk-------------------
3846c609719bSwdenk
3847c609719bSwdenkSince the number of patches for U-Boot is growing, we need to
3848c609719bSwdenkestablish some rules. Submissions which do not conform to these rules
3849c609719bSwdenkmay be rejected, even when they contain important and valuable stuff.
3850c609719bSwdenk
385190dc6704SwdenkPatches shall be sent to the u-boot-users mailing list.
3852c609719bSwdenk
3853218ca724SWolfgang DenkPlease see http://www.denx.de/wiki/UBoot/Patches for details.
3854218ca724SWolfgang Denk
3855c609719bSwdenkWhen you send a patch, please include the following information with
3856c609719bSwdenkit:
3857c609719bSwdenk
3858c609719bSwdenk* For bug fixes: a description of the bug and how your patch fixes
3859c609719bSwdenk  this bug. Please try to include a way of demonstrating that the
3860c609719bSwdenk  patch actually fixes something.
3861c609719bSwdenk
3862c609719bSwdenk* For new features: a description of the feature and your
3863c609719bSwdenk  implementation.
3864c609719bSwdenk
3865c609719bSwdenk* A CHANGELOG entry as plaintext (separate from the patch)
3866c609719bSwdenk
3867c609719bSwdenk* For major contributions, your entry to the CREDITS file
3868c609719bSwdenk
3869c609719bSwdenk* When you add support for a new board, don't forget to add this
3870c609719bSwdenk  board to the MAKEALL script, too.
3871c609719bSwdenk
3872c609719bSwdenk* If your patch adds new configuration options, don't forget to
3873c609719bSwdenk  document these in the README file.
3874c609719bSwdenk
3875218ca724SWolfgang Denk* The patch itself. If you are using git (which is *strongly*
3876218ca724SWolfgang Denk  recommended) you can easily generate the patch using the
3877218ca724SWolfgang Denk  "git-format-patch". If you then use "git-send-email" to send it to
3878218ca724SWolfgang Denk  the U-Boot mailing list, you will avoid most of the common problems
3879218ca724SWolfgang Denk  with some other mail clients.
3880c609719bSwdenk
3881218ca724SWolfgang Denk  If you cannot use git, use "diff -purN OLD NEW". If your version of
3882218ca724SWolfgang Denk  diff does not support these options, then get the latest version of
3883218ca724SWolfgang Denk  GNU diff.
38846dff5529Swdenk
3885218ca724SWolfgang Denk  The current directory when running this command shall be the parent
3886218ca724SWolfgang Denk  directory of the U-Boot source tree (i. e. please make sure that
3887218ca724SWolfgang Denk  your patch includes sufficient directory information for the
3888218ca724SWolfgang Denk  affected files).
3889218ca724SWolfgang Denk
3890218ca724SWolfgang Denk  We prefer patches as plain text. MIME attachments are discouraged,
3891218ca724SWolfgang Denk  and compressed attachments must not be used.
3892c609719bSwdenk
389352f52c14Swdenk* If one logical set of modifications affects or creates several
389452f52c14Swdenk  files, all these changes shall be submitted in a SINGLE patch file.
389552f52c14Swdenk
389652f52c14Swdenk* Changesets that contain different, unrelated modifications shall be
389752f52c14Swdenk  submitted as SEPARATE patches, one patch per changeset.
389852f52c14Swdenk
389952f52c14Swdenk
3900c609719bSwdenkNotes:
3901c609719bSwdenk
3902c609719bSwdenk* Before sending the patch, run the MAKEALL script on your patched
3903c609719bSwdenk  source tree and make sure that no errors or warnings are reported
3904c609719bSwdenk  for any of the boards.
3905c609719bSwdenk
3906c609719bSwdenk* Keep your modifications to the necessary minimum: A patch
3907c609719bSwdenk  containing several unrelated changes or arbitrary reformats will be
3908c609719bSwdenk  returned with a request to re-formatting / split it.
3909c609719bSwdenk
3910c609719bSwdenk* If you modify existing code, make sure that your new code does not
3911c609719bSwdenk  add to the memory footprint of the code ;-) Small is beautiful!
3912c609719bSwdenk  When adding new features, these should compile conditionally only
3913c609719bSwdenk  (using #ifdef), and the resulting code with the new feature
3914c609719bSwdenk  disabled must not need more memory than the old code without your
3915c609719bSwdenk  modification.
391690dc6704Swdenk
391790dc6704Swdenk* Remember that there is a size limit of 40 kB per message on the
3918218ca724SWolfgang Denk  u-boot-users mailing list. Bigger patches will be moderated. If
3919218ca724SWolfgang Denk  they are reasonable and not bigger than 100 kB, they will be
3920218ca724SWolfgang Denk  acknowledged. Even bigger patches should be avoided.
3921