2 # (C) Copyright 2000 - 2009
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
129 U-Boot uses a 3 level version number containing a version, a
130 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
131 sub-version "34", and patchlevel "4".
133 The patchlevel is used to indicate certain stages of development
134 between released versions, i. e. officially released versions of
135 U-Boot will always have a patchlevel of "0".
141 /arch Architecture specific files
142 /arm Files generic to ARM architecture
143 /cpu CPU specific files
144 /arm720t Files specific to ARM 720 CPUs
145 /arm920t Files specific to ARM 920 CPUs
146 /at91rm9200 Files specific to Atmel AT91RM9200 CPU
147 /imx Files specific to Freescale MC9328 i.MX CPUs
148 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
149 /arm925t Files specific to ARM 925 CPUs
150 /arm926ejs Files specific to ARM 926 CPUs
151 /arm1136 Files specific to ARM 1136 CPUs
152 /ixp Files specific to Intel XScale IXP CPUs
153 /pxa Files specific to Intel XScale PXA CPUs
154 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
155 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
156 /lib Architecture specific library files
157 /avr32 Files generic to AVR32 architecture
158 /cpu CPU specific files
159 /lib Architecture specific library files
160 /blackfin Files generic to Analog Devices Blackfin architecture
161 /cpu CPU specific files
162 /lib Architecture specific library files
163 /i386 Files generic to i386 architecture
164 /cpu CPU specific files
165 /lib Architecture specific library files
166 /m68k Files generic to m68k architecture
167 /cpu CPU specific files
168 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
169 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
170 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
171 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
172 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
173 /lib Architecture specific library files
174 /microblaze Files generic to microblaze architecture
175 /cpu CPU specific files
176 /lib Architecture specific library files
177 /mips Files generic to MIPS architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /nios2 Files generic to Altera NIOS2 architecture
181 /cpu CPU specific files
182 /lib Architecture specific library files
183 /powerpc Files generic to PowerPC architecture
184 /cpu CPU specific files
185 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
186 /mpc5xx Files specific to Freescale MPC5xx CPUs
187 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
188 /mpc8xx Files specific to Freescale MPC8xx CPUs
189 /mpc8220 Files specific to Freescale MPC8220 CPUs
190 /mpc824x Files specific to Freescale MPC824x CPUs
191 /mpc8260 Files specific to Freescale MPC8260 CPUs
192 /mpc85xx Files specific to Freescale MPC85xx CPUs
193 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
194 /lib Architecture specific library files
195 /sh Files generic to SH architecture
196 /cpu CPU specific files
197 /sh2 Files specific to sh2 CPUs
198 /sh3 Files specific to sh3 CPUs
199 /sh4 Files specific to sh4 CPUs
200 /lib Architecture specific library files
201 /sparc Files generic to SPARC architecture
202 /cpu CPU specific files
203 /leon2 Files specific to Gaisler LEON2 SPARC CPU
204 /leon3 Files specific to Gaisler LEON3 SPARC CPU
205 /lib Architecture specific library files
206 /api Machine/arch independent API for external apps
207 /board Board dependent files
208 /common Misc architecture independent functions
209 /disk Code for disk drive partition handling
210 /doc Documentation (don't expect too much)
211 /drivers Commonly used device drivers
212 /examples Example code for standalone applications, etc.
213 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
214 /include Header Files
215 /lib Files generic to all architectures
216 /libfdt Library files to support flattened device trees
217 /lzma Library files to support LZMA decompression
218 /lzo Library files to support LZO decompression
220 /post Power On Self Test
221 /rtc Real Time Clock drivers
222 /tools Tools to build S-Record or U-Boot images, etc.
224 Software Configuration:
225 =======================
227 Configuration is usually done using C preprocessor defines; the
228 rationale behind that is to avoid dead code whenever possible.
230 There are two classes of configuration variables:
232 * Configuration _OPTIONS_:
233 These are selectable by the user and have names beginning with
236 * Configuration _SETTINGS_:
237 These depend on the hardware etc. and should not be meddled with if
238 you don't know what you're doing; they have names beginning with
241 Later we will add a configuration tool - probably similar to or even
242 identical to what's used for the Linux kernel. Right now, we have to
243 do the configuration by hand, which means creating some symbolic
244 links and editing some configuration files. We use the TQM8xxL boards
248 Selection of Processor Architecture and Board Type:
249 ---------------------------------------------------
251 For all supported boards there are ready-to-use default
252 configurations available; just type "make <board_name>_config".
254 Example: For a TQM823L module type:
259 For the Cogent platform, you need to specify the CPU type as well;
260 e.g. "make cogent_mpc8xx_config". And also configure the cogent
261 directory according to the instructions in cogent/README.
264 Configuration Options:
265 ----------------------
267 Configuration depends on the combination of board and CPU type; all
268 such information is kept in a configuration file
269 "include/configs/<board_name>.h".
271 Example: For a TQM823L module, all configuration settings are in
272 "include/configs/TQM823L.h".
275 Many of the options are named exactly as the corresponding Linux
276 kernel configuration options. The intention is to make it easier to
277 build a config tool - later.
280 The following options need to be configured:
282 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
284 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
286 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
287 Define exactly one, e.g. CONFIG_ATSTK1002
289 - CPU Module Type: (if CONFIG_COGENT is defined)
290 Define exactly one of
292 --- FIXME --- not tested yet:
293 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
294 CONFIG_CMA287_23, CONFIG_CMA287_50
296 - Motherboard Type: (if CONFIG_COGENT is defined)
297 Define exactly one of
298 CONFIG_CMA101, CONFIG_CMA102
300 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
301 Define one or more of
304 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
305 Define one or more of
306 CONFIG_LCD_HEARTBEAT - update a character position on
307 the LCD display every second with
310 - Board flavour: (if CONFIG_MPC8260ADS is defined)
313 CONFIG_SYS_8260ADS - original MPC8260ADS
314 CONFIG_SYS_8266ADS - MPC8266ADS
315 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
316 CONFIG_SYS_8272ADS - MPC8272ADS
318 - MPC824X Family Member (if CONFIG_MPC824X is defined)
319 Define exactly one of
320 CONFIG_MPC8240, CONFIG_MPC8245
322 - 8xx CPU Options: (if using an MPC8xx CPU)
323 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
324 get_gclk_freq() cannot work
325 e.g. if there is no 32KHz
326 reference PIT/RTC clock
327 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
330 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
331 CONFIG_SYS_8xx_CPUCLK_MIN
332 CONFIG_SYS_8xx_CPUCLK_MAX
333 CONFIG_8xx_CPUCLK_DEFAULT
334 See doc/README.MPC866
336 CONFIG_SYS_MEASURE_CPUCLK
338 Define this to measure the actual CPU clock instead
339 of relying on the correctness of the configured
340 values. Mostly useful for board bringup to make sure
341 the PLL is locked at the intended frequency. Note
342 that this requires a (stable) reference clock (32 kHz
343 RTC clock or CONFIG_SYS_8XX_XIN)
345 CONFIG_SYS_DELAYED_ICACHE
347 Define this option if you want to enable the
348 ICache only when Code runs from RAM.
350 - Intel Monahans options:
351 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
353 Defines the Monahans run mode to oscillator
354 ratio. Valid values are 8, 16, 24, 31. The core
355 frequency is this value multiplied by 13 MHz.
357 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
359 Defines the Monahans turbo mode to oscillator
360 ratio. Valid values are 1 (default if undefined) and
361 2. The core frequency as calculated above is multiplied
364 - Linux Kernel Interface:
367 U-Boot stores all clock information in Hz
368 internally. For binary compatibility with older Linux
369 kernels (which expect the clocks passed in the
370 bd_info data to be in MHz) the environment variable
371 "clocks_in_mhz" can be defined so that U-Boot
372 converts clock data to MHZ before passing it to the
374 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
375 "clocks_in_mhz=1" is automatically included in the
378 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
380 When transferring memsize parameter to linux, some versions
381 expect it to be in bytes, others in MB.
382 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
386 New kernel versions are expecting firmware settings to be
387 passed using flattened device trees (based on open firmware
391 * New libfdt-based support
392 * Adds the "fdt" command
393 * The bootm command automatically updates the fdt
395 OF_CPU - The proper name of the cpus node (only required for
396 MPC512X and MPC5xxx based boards).
397 OF_SOC - The proper name of the soc node (only required for
398 MPC512X and MPC5xxx based boards).
399 OF_TBCLK - The timebase frequency.
400 OF_STDOUT_PATH - The path to the console device
402 boards with QUICC Engines require OF_QE to set UCC MAC
405 CONFIG_OF_BOARD_SETUP
407 Board code has addition modification that it wants to make
408 to the flat device tree before handing it off to the kernel
412 This define fills in the correct boot CPU in the boot
413 param header, the default value is zero if undefined.
417 U-Boot can detect if an IDE device is present or not.
418 If not, and this new config option is activated, U-Boot
419 removes the ATA node from the DTS before booting Linux,
420 so the Linux IDE driver does not probe the device and
421 crash. This is needed for buggy hardware (uc101) where
422 no pull down resistor is connected to the signal IDE5V_DD7.
424 - vxWorks boot parameters:
426 bootvx constructs a valid bootline using the following
427 environments variables: bootfile, ipaddr, serverip, hostname.
428 It loads the vxWorks image pointed bootfile.
430 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
431 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
432 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
433 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
435 CONFIG_SYS_VXWORKS_ADD_PARAMS
437 Add it at the end of the bootline. E.g "u=username pw=secret"
439 Note: If a "bootargs" environment is defined, it will overwride
440 the defaults discussed just above.
445 Define this if you want support for Amba PrimeCell PL010 UARTs.
449 Define this if you want support for Amba PrimeCell PL011 UARTs.
453 If you have Amba PrimeCell PL011 UARTs, set this variable to
454 the clock speed of the UARTs.
458 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
459 define this to a list of base addresses for each (supported)
460 port. See e.g. include/configs/versatile.h
464 Depending on board, define exactly one serial port
465 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
466 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
467 console by defining CONFIG_8xx_CONS_NONE
469 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
470 port routines must be defined elsewhere
471 (i.e. serial_init(), serial_getc(), ...)
474 Enables console device for a color framebuffer. Needs following
475 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
476 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
478 VIDEO_HW_RECTFILL graphic chip supports
481 VIDEO_HW_BITBLT graphic chip supports
482 bit-blit (cf. smiLynxEM)
483 VIDEO_VISIBLE_COLS visible pixel columns
485 VIDEO_VISIBLE_ROWS visible pixel rows
486 VIDEO_PIXEL_SIZE bytes per pixel
487 VIDEO_DATA_FORMAT graphic data format
488 (0-5, cf. cfb_console.c)
489 VIDEO_FB_ADRS framebuffer address
490 VIDEO_KBD_INIT_FCT keyboard int fct
491 (i.e. i8042_kbd_init())
492 VIDEO_TSTC_FCT test char fct
494 VIDEO_GETC_FCT get char fct
496 CONFIG_CONSOLE_CURSOR cursor drawing on/off
497 (requires blink timer
499 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
500 CONFIG_CONSOLE_TIME display time/date info in
502 (requires CONFIG_CMD_DATE)
503 CONFIG_VIDEO_LOGO display Linux logo in
505 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
506 linux_logo.h for logo.
507 Requires CONFIG_VIDEO_LOGO
508 CONFIG_CONSOLE_EXTRA_INFO
509 additional board info beside
512 When CONFIG_CFB_CONSOLE is defined, video console is
513 default i/o. Serial console can be forced with
514 environment 'console=serial'.
516 When CONFIG_SILENT_CONSOLE is defined, all console
517 messages (by U-Boot and Linux!) can be silenced with
518 the "silent" environment variable. See
519 doc/README.silent for more information.
522 CONFIG_BAUDRATE - in bps
523 Select one of the baudrates listed in
524 CONFIG_SYS_BAUDRATE_TABLE, see below.
525 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
527 - Console Rx buffer length
528 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
529 the maximum receive buffer length for the SMC.
530 This option is actual only for 82xx and 8xx possible.
531 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
532 must be defined, to setup the maximum idle timeout for
535 - Boot Delay: CONFIG_BOOTDELAY - in seconds
536 Delay before automatically booting the default image;
537 set to -1 to disable autoboot.
539 See doc/README.autoboot for these options that
540 work with CONFIG_BOOTDELAY. None are required.
541 CONFIG_BOOT_RETRY_TIME
542 CONFIG_BOOT_RETRY_MIN
543 CONFIG_AUTOBOOT_KEYED
544 CONFIG_AUTOBOOT_PROMPT
545 CONFIG_AUTOBOOT_DELAY_STR
546 CONFIG_AUTOBOOT_STOP_STR
547 CONFIG_AUTOBOOT_DELAY_STR2
548 CONFIG_AUTOBOOT_STOP_STR2
549 CONFIG_ZERO_BOOTDELAY_CHECK
550 CONFIG_RESET_TO_RETRY
554 Only needed when CONFIG_BOOTDELAY is enabled;
555 define a command string that is automatically executed
556 when no character is read on the console interface
557 within "Boot Delay" after reset.
560 This can be used to pass arguments to the bootm
561 command. The value of CONFIG_BOOTARGS goes into the
562 environment value "bootargs".
564 CONFIG_RAMBOOT and CONFIG_NFSBOOT
565 The value of these goes into the environment as
566 "ramboot" and "nfsboot" respectively, and can be used
567 as a convenience, when switching between booting from
573 When this option is #defined, the existence of the
574 environment variable "preboot" will be checked
575 immediately before starting the CONFIG_BOOTDELAY
576 countdown and/or running the auto-boot command resp.
577 entering interactive mode.
579 This feature is especially useful when "preboot" is
580 automatically generated or modified. For an example
581 see the LWMON board specific code: here "preboot" is
582 modified when the user holds down a certain
583 combination of keys on the (special) keyboard when
586 - Serial Download Echo Mode:
588 If defined to 1, all characters received during a
589 serial download (using the "loads" command) are
590 echoed back. This might be needed by some terminal
591 emulations (like "cu"), but may as well just take
592 time on others. This setting #define's the initial
593 value of the "loads_echo" environment variable.
595 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
597 Select one of the baudrates listed in
598 CONFIG_SYS_BAUDRATE_TABLE, see below.
601 Monitor commands can be included or excluded
602 from the build by using the #include files
603 "config_cmd_all.h" and #undef'ing unwanted
604 commands, or using "config_cmd_default.h"
605 and augmenting with additional #define's
608 The default command configuration includes all commands
609 except those marked below with a "*".
611 CONFIG_CMD_ASKENV * ask for env variable
612 CONFIG_CMD_BDI bdinfo
613 CONFIG_CMD_BEDBUG * Include BedBug Debugger
614 CONFIG_CMD_BMP * BMP support
615 CONFIG_CMD_BSP * Board specific commands
616 CONFIG_CMD_BOOTD bootd
617 CONFIG_CMD_CACHE * icache, dcache
618 CONFIG_CMD_CONSOLE coninfo
619 CONFIG_CMD_DATE * support for RTC, date/time...
620 CONFIG_CMD_DHCP * DHCP support
621 CONFIG_CMD_DIAG * Diagnostics
622 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
623 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
624 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
625 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
626 CONFIG_CMD_DTT * Digital Therm and Thermostat
627 CONFIG_CMD_ECHO echo arguments
628 CONFIG_CMD_EDITENV edit env variable
629 CONFIG_CMD_EEPROM * EEPROM read/write support
630 CONFIG_CMD_ELF * bootelf, bootvx
631 CONFIG_CMD_SAVEENV saveenv
632 CONFIG_CMD_FDC * Floppy Disk Support
633 CONFIG_CMD_FAT * FAT partition support
634 CONFIG_CMD_FDOS * Dos diskette Support
635 CONFIG_CMD_FLASH flinfo, erase, protect
636 CONFIG_CMD_FPGA FPGA device initialization support
637 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
638 CONFIG_CMD_I2C * I2C serial bus support
639 CONFIG_CMD_IDE * IDE harddisk support
640 CONFIG_CMD_IMI iminfo
641 CONFIG_CMD_IMLS List all found images
642 CONFIG_CMD_IMMAP * IMMR dump support
643 CONFIG_CMD_IRQ * irqinfo
644 CONFIG_CMD_ITEST Integer/string test of 2 values
645 CONFIG_CMD_JFFS2 * JFFS2 Support
646 CONFIG_CMD_KGDB * kgdb
647 CONFIG_CMD_LOADB loadb
648 CONFIG_CMD_LOADS loads
649 CONFIG_CMD_MD5SUM print md5 message digest
650 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
651 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
653 CONFIG_CMD_MISC Misc functions like sleep etc
654 CONFIG_CMD_MMC * MMC memory mapped support
655 CONFIG_CMD_MII * MII utility commands
656 CONFIG_CMD_MTDPARTS * MTD partition support
657 CONFIG_CMD_NAND * NAND support
658 CONFIG_CMD_NET bootp, tftpboot, rarpboot
659 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
660 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
661 CONFIG_CMD_PCI * pciinfo
662 CONFIG_CMD_PCMCIA * PCMCIA support
663 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
665 CONFIG_CMD_PORTIO * Port I/O
666 CONFIG_CMD_REGINFO * Register dump
667 CONFIG_CMD_RUN run command in env variable
668 CONFIG_CMD_SAVES * save S record dump
669 CONFIG_CMD_SCSI * SCSI Support
670 CONFIG_CMD_SDRAM * print SDRAM configuration information
671 (requires CONFIG_CMD_I2C)
672 CONFIG_CMD_SETGETDCR Support for DCR Register access
674 CONFIG_CMD_SHA1 print sha1 memory digest
675 (requires CONFIG_CMD_MEMORY)
676 CONFIG_CMD_SOURCE "source" command Support
677 CONFIG_CMD_SPI * SPI serial bus support
678 CONFIG_CMD_USB * USB support
679 CONFIG_CMD_VFD * VFD support (TRAB)
680 CONFIG_CMD_CDP * Cisco Discover Protocol support
681 CONFIG_CMD_FSL * Microblaze FSL support
684 EXAMPLE: If you want all functions except of network
685 support you can write:
687 #include "config_cmd_all.h"
688 #undef CONFIG_CMD_NET
691 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
693 Note: Don't enable the "icache" and "dcache" commands
694 (configuration option CONFIG_CMD_CACHE) unless you know
695 what you (and your U-Boot users) are doing. Data
696 cache cannot be enabled on systems like the 8xx or
697 8260 (where accesses to the IMMR region must be
698 uncached), and it cannot be disabled on all other
699 systems where we (mis-) use the data cache to hold an
700 initial stack and some data.
703 XXX - this list needs to get updated!
707 If this variable is defined, it enables watchdog
708 support. There must be support in the platform specific
709 code for a watchdog. For the 8xx and 8260 CPUs, the
710 SIU Watchdog feature is enabled in the SYPCR
714 CONFIG_VERSION_VARIABLE
715 If this variable is defined, an environment variable
716 named "ver" is created by U-Boot showing the U-Boot
717 version as printed by the "version" command.
718 This variable is readonly.
722 When CONFIG_CMD_DATE is selected, the type of the RTC
723 has to be selected, too. Define exactly one of the
726 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
727 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
728 CONFIG_RTC_MC13783 - use MC13783 RTC
729 CONFIG_RTC_MC146818 - use MC146818 RTC
730 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
731 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
732 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
733 CONFIG_RTC_DS164x - use Dallas DS164x RTC
734 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
735 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
736 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
738 Note that if the RTC uses I2C, then the I2C interface
739 must also be configured. See I2C Support, below.
742 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
743 CONFIG_PCA953X_INFO - enable pca953x info command
745 Note that if the GPIO device uses I2C, then the I2C interface
746 must also be configured. See I2C Support, below.
750 When CONFIG_TIMESTAMP is selected, the timestamp
751 (date and time) of an image is printed by image
752 commands like bootm or iminfo. This option is
753 automatically enabled when you select CONFIG_CMD_DATE .
756 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
757 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
759 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
760 CONFIG_CMD_SCSI) you must configure support for at
761 least one partition type as well.
764 CONFIG_IDE_RESET_ROUTINE - this is defined in several
765 board configurations files but used nowhere!
767 CONFIG_IDE_RESET - is this is defined, IDE Reset will
768 be performed by calling the function
769 ide_set_reset(int reset)
770 which has to be defined in a board specific file
775 Set this to enable ATAPI support.
780 Set this to enable support for disks larger than 137GB
781 Also look at CONFIG_SYS_64BIT_LBA.
782 Whithout these , LBA48 support uses 32bit variables and will 'only'
783 support disks up to 2.1TB.
785 CONFIG_SYS_64BIT_LBA:
786 When enabled, makes the IDE subsystem use 64bit sector addresses.
790 At the moment only there is only support for the
791 SYM53C8XX SCSI controller; define
792 CONFIG_SCSI_SYM53C8XX to enable it.
794 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
795 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
796 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
797 maximum numbers of LUNs, SCSI ID's and target
799 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
801 - NETWORK Support (PCI):
803 Support for Intel 8254x gigabit chips.
805 CONFIG_E1000_FALLBACK_MAC
806 default MAC for empty EEPROM after production.
809 Support for Intel 82557/82559/82559ER chips.
810 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
811 write routine for first time initialisation.
814 Support for Digital 2114x chips.
815 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
816 modem chip initialisation (KS8761/QS6611).
819 Support for National dp83815 chips.
822 Support for National dp8382[01] gigabit chips.
824 - NETWORK Support (other):
826 CONFIG_DRIVER_AT91EMAC
827 Support for AT91RM9200 EMAC.
830 Define this to use reduced MII inteface
832 CONFIG_DRIVER_AT91EMAC_QUIET
833 If this defined, the driver is quiet.
834 The driver doen't show link status messages.
836 CONFIG_DRIVER_LAN91C96
837 Support for SMSC's LAN91C96 chips.
840 Define this to hold the physical address
841 of the LAN91C96's I/O space
843 CONFIG_LAN91C96_USE_32_BIT
844 Define this to enable 32 bit addressing
846 CONFIG_DRIVER_SMC91111
847 Support for SMSC's LAN91C111 chip
850 Define this to hold the physical address
851 of the device (I/O space)
853 CONFIG_SMC_USE_32_BIT
854 Define this if data bus is 32 bits
856 CONFIG_SMC_USE_IOFUNCS
857 Define this to use i/o functions instead of macros
858 (some hardware wont work with macros)
861 Support for SMSC's LAN911x and LAN921x chips
864 Define this to hold the physical address
865 of the device (I/O space)
867 CONFIG_SMC911X_32_BIT
868 Define this if data bus is 32 bits
870 CONFIG_SMC911X_16_BIT
871 Define this if data bus is 16 bits. If your processor
872 automatically converts one 32 bit word to two 16 bit
873 words you may also try CONFIG_SMC911X_32_BIT.
876 At the moment only the UHCI host controller is
877 supported (PIP405, MIP405, MPC5200); define
878 CONFIG_USB_UHCI to enable it.
879 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
880 and define CONFIG_USB_STORAGE to enable the USB
883 Supported are USB Keyboards and USB Floppy drives
885 MPC5200 USB requires additional defines:
887 for 528 MHz Clock: 0x0001bbbb
891 for differential drivers: 0x00001000
892 for single ended drivers: 0x00005000
893 for differential drivers on PSC3: 0x00000100
894 for single ended drivers on PSC3: 0x00004100
895 CONFIG_SYS_USB_EVENT_POLL
896 May be defined to allow interrupt polling
897 instead of using asynchronous interrupts
900 Define the below if you wish to use the USB console.
901 Once firmware is rebuilt from a serial console issue the
902 command "setenv stdin usbtty; setenv stdout usbtty" and
903 attach your USB cable. The Unix command "dmesg" should print
904 it has found a new device. The environment variable usbtty
905 can be set to gserial or cdc_acm to enable your device to
906 appear to a USB host as a Linux gserial device or a
907 Common Device Class Abstract Control Model serial device.
908 If you select usbtty = gserial you should be able to enumerate
910 # modprobe usbserial vendor=0xVendorID product=0xProductID
911 else if using cdc_acm, simply setting the environment
912 variable usbtty to be cdc_acm should suffice. The following
913 might be defined in YourBoardName.h
916 Define this to build a UDC device
919 Define this to have a tty type of device available to
920 talk to the UDC device
922 CONFIG_SYS_CONSOLE_IS_IN_ENV
923 Define this if you want stdin, stdout &/or stderr to
927 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
928 Derive USB clock from external clock "blah"
929 - CONFIG_SYS_USB_EXTC_CLK 0x02
931 CONFIG_SYS_USB_BRG_CLK 0xBLAH
932 Derive USB clock from brgclk
933 - CONFIG_SYS_USB_BRG_CLK 0x04
935 If you have a USB-IF assigned VendorID then you may wish to
936 define your own vendor specific values either in BoardName.h
937 or directly in usbd_vendor_info.h. If you don't define
938 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
939 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
940 should pretend to be a Linux device to it's target host.
942 CONFIG_USBD_MANUFACTURER
943 Define this string as the name of your company for
944 - CONFIG_USBD_MANUFACTURER "my company"
946 CONFIG_USBD_PRODUCT_NAME
947 Define this string as the name of your product
948 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
951 Define this as your assigned Vendor ID from the USB
952 Implementors Forum. This *must* be a genuine Vendor ID
953 to avoid polluting the USB namespace.
954 - CONFIG_USBD_VENDORID 0xFFFF
956 CONFIG_USBD_PRODUCTID
957 Define this as the unique Product ID
959 - CONFIG_USBD_PRODUCTID 0xFFFF
963 The MMC controller on the Intel PXA is supported. To
964 enable this define CONFIG_MMC. The MMC can be
965 accessed from the boot prompt by mapping the device
966 to physical memory similar to flash. Command line is
967 enabled with CONFIG_CMD_MMC. The MMC driver also works with
968 the FAT fs. This is enabled with CONFIG_CMD_FAT.
970 - Journaling Flash filesystem support:
971 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
972 CONFIG_JFFS2_NAND_DEV
973 Define these for a default partition on a NAND device
975 CONFIG_SYS_JFFS2_FIRST_SECTOR,
976 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
977 Define these for a default partition on a NOR device
979 CONFIG_SYS_JFFS_CUSTOM_PART
980 Define this to create an own partition. You have to provide a
981 function struct part_info* jffs2_part_info(int part_num)
983 If you define only one JFFS2 partition you may also want to
984 #define CONFIG_SYS_JFFS_SINGLE_PART 1
985 to disable the command chpart. This is the default when you
986 have not defined a custom partition
991 Define this to enable standard (PC-Style) keyboard
995 Standard PC keyboard driver with US (is default) and
996 GERMAN key layout (switch via environment 'keymap=de') support.
997 Export function i8042_kbd_init, i8042_tstc and i8042_getc
998 for cfb_console. Supports cursor blinking.
1003 Define this to enable video support (for output to
1006 CONFIG_VIDEO_CT69000
1008 Enable Chips & Technologies 69000 Video chip
1010 CONFIG_VIDEO_SMI_LYNXEM
1011 Enable Silicon Motion SMI 712/710/810 Video chip. The
1012 video output is selected via environment 'videoout'
1013 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1016 For the CT69000 and SMI_LYNXEM drivers, videomode is
1017 selected via environment 'videomode'. Two different ways
1019 - "videomode=num" 'num' is a standard LiLo mode numbers.
1020 Following standard modes are supported (* is default):
1022 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1023 -------------+---------------------------------------------
1024 8 bits | 0x301* 0x303 0x305 0x161 0x307
1025 15 bits | 0x310 0x313 0x316 0x162 0x319
1026 16 bits | 0x311 0x314 0x317 0x163 0x31A
1027 24 bits | 0x312 0x315 0x318 ? 0x31B
1028 -------------+---------------------------------------------
1029 (i.e. setenv videomode 317; saveenv; reset;)
1031 - "videomode=bootargs" all the video parameters are parsed
1032 from the bootargs. (See drivers/video/videomodes.c)
1035 CONFIG_VIDEO_SED13806
1036 Enable Epson SED13806 driver. This driver supports 8bpp
1037 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1038 or CONFIG_VIDEO_SED13806_16BPP
1043 Define this to enable a custom keyboard support.
1044 This simply calls drv_keyboard_init() which must be
1045 defined in your board-specific files.
1046 The only board using this so far is RBC823.
1048 - LCD Support: CONFIG_LCD
1050 Define this to enable LCD support (for output to LCD
1051 display); also select one of the supported displays
1052 by defining one of these:
1056 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1058 CONFIG_NEC_NL6448AC33:
1060 NEC NL6448AC33-18. Active, color, single scan.
1062 CONFIG_NEC_NL6448BC20
1064 NEC NL6448BC20-08. 6.5", 640x480.
1065 Active, color, single scan.
1067 CONFIG_NEC_NL6448BC33_54
1069 NEC NL6448BC33-54. 10.4", 640x480.
1070 Active, color, single scan.
1074 Sharp 320x240. Active, color, single scan.
1075 It isn't 16x9, and I am not sure what it is.
1077 CONFIG_SHARP_LQ64D341
1079 Sharp LQ64D341 display, 640x480.
1080 Active, color, single scan.
1084 HLD1045 display, 640x480.
1085 Active, color, single scan.
1089 Optrex CBL50840-2 NF-FW 99 22 M5
1091 Hitachi LMG6912RPFC-00T
1095 320x240. Black & white.
1097 Normally display is black on white background; define
1098 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1100 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1102 If this option is set, the environment is checked for
1103 a variable "splashimage". If found, the usual display
1104 of logo, copyright and system information on the LCD
1105 is suppressed and the BMP image at the address
1106 specified in "splashimage" is loaded instead. The
1107 console is redirected to the "nulldev", too. This
1108 allows for a "silent" boot where a splash screen is
1109 loaded very quickly after power-on.
1111 CONFIG_SPLASH_SCREEN_ALIGN
1113 If this option is set the splash image can be freely positioned
1114 on the screen. Environment variable "splashpos" specifies the
1115 position as "x,y". If a positive number is given it is used as
1116 number of pixel from left/top. If a negative number is given it
1117 is used as number of pixel from right/bottom. You can also
1118 specify 'm' for centering the image.
1121 setenv splashpos m,m
1122 => image at center of screen
1124 setenv splashpos 30,20
1125 => image at x = 30 and y = 20
1127 setenv splashpos -10,m
1128 => vertically centered image
1129 at x = dspWidth - bmpWidth - 9
1131 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1133 If this option is set, additionally to standard BMP
1134 images, gzipped BMP images can be displayed via the
1135 splashscreen support or the bmp command.
1137 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1139 If this option is set, 8-bit RLE compressed BMP images
1140 can be displayed via the splashscreen support or the
1143 - Compression support:
1146 If this option is set, support for bzip2 compressed
1147 images is included. If not, only uncompressed and gzip
1148 compressed images are supported.
1150 NOTE: the bzip2 algorithm requires a lot of RAM, so
1151 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1156 If this option is set, support for lzma compressed
1159 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1160 requires an amount of dynamic memory that is given by the
1163 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1165 Where lc and lp stand for, respectively, Literal context bits
1166 and Literal pos bits.
1168 This value is upper-bounded by 14MB in the worst case. Anyway,
1169 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1170 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1171 a very small buffer.
1173 Use the lzmainfo tool to determinate the lc and lp values and
1174 then calculate the amount of needed dynamic memory (ensuring
1175 the appropriate CONFIG_SYS_MALLOC_LEN value).
1180 The address of PHY on MII bus.
1182 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1184 The clock frequency of the MII bus
1188 If this option is set, support for speed/duplex
1189 detection of gigabit PHY is included.
1191 CONFIG_PHY_RESET_DELAY
1193 Some PHY like Intel LXT971A need extra delay after
1194 reset before any MII register access is possible.
1195 For such PHY, set this option to the usec delay
1196 required. (minimum 300usec for LXT971A)
1198 CONFIG_PHY_CMD_DELAY (ppc4xx)
1200 Some PHY like Intel LXT971A need extra delay after
1201 command issued before MII status register can be read
1211 Define a default value for Ethernet address to use
1212 for the respective Ethernet interface, in case this
1213 is not determined automatically.
1218 Define a default value for the IP address to use for
1219 the default Ethernet interface, in case this is not
1220 determined through e.g. bootp.
1222 - Server IP address:
1225 Defines a default value for the IP address of a TFTP
1226 server to contact when using the "tftboot" command.
1228 CONFIG_KEEP_SERVERADDR
1230 Keeps the server's MAC address, in the env 'serveraddr'
1231 for passing to bootargs (like Linux's netconsole option)
1233 - Multicast TFTP Mode:
1236 Defines whether you want to support multicast TFTP as per
1237 rfc-2090; for example to work with atftp. Lets lots of targets
1238 tftp down the same boot image concurrently. Note: the Ethernet
1239 driver in use must provide a function: mcast() to join/leave a
1242 CONFIG_BOOTP_RANDOM_DELAY
1243 - BOOTP Recovery Mode:
1244 CONFIG_BOOTP_RANDOM_DELAY
1246 If you have many targets in a network that try to
1247 boot using BOOTP, you may want to avoid that all
1248 systems send out BOOTP requests at precisely the same
1249 moment (which would happen for instance at recovery
1250 from a power failure, when all systems will try to
1251 boot, thus flooding the BOOTP server. Defining
1252 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1253 inserted before sending out BOOTP requests. The
1254 following delays are inserted then:
1256 1st BOOTP request: delay 0 ... 1 sec
1257 2nd BOOTP request: delay 0 ... 2 sec
1258 3rd BOOTP request: delay 0 ... 4 sec
1260 BOOTP requests: delay 0 ... 8 sec
1262 - DHCP Advanced Options:
1263 You can fine tune the DHCP functionality by defining
1264 CONFIG_BOOTP_* symbols:
1266 CONFIG_BOOTP_SUBNETMASK
1267 CONFIG_BOOTP_GATEWAY
1268 CONFIG_BOOTP_HOSTNAME
1269 CONFIG_BOOTP_NISDOMAIN
1270 CONFIG_BOOTP_BOOTPATH
1271 CONFIG_BOOTP_BOOTFILESIZE
1274 CONFIG_BOOTP_SEND_HOSTNAME
1275 CONFIG_BOOTP_NTPSERVER
1276 CONFIG_BOOTP_TIMEOFFSET
1277 CONFIG_BOOTP_VENDOREX
1279 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1280 environment variable, not the BOOTP server.
1282 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1283 serverip from a DHCP server, it is possible that more
1284 than one DNS serverip is offered to the client.
1285 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1286 serverip will be stored in the additional environment
1287 variable "dnsip2". The first DNS serverip is always
1288 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1291 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1292 to do a dynamic update of a DNS server. To do this, they
1293 need the hostname of the DHCP requester.
1294 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1295 of the "hostname" environment variable is passed as
1296 option 12 to the DHCP server.
1298 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1300 A 32bit value in microseconds for a delay between
1301 receiving a "DHCP Offer" and sending the "DHCP Request".
1302 This fixes a problem with certain DHCP servers that don't
1303 respond 100% of the time to a "DHCP request". E.g. On an
1304 AT91RM9200 processor running at 180MHz, this delay needed
1305 to be *at least* 15,000 usec before a Windows Server 2003
1306 DHCP server would reply 100% of the time. I recommend at
1307 least 50,000 usec to be safe. The alternative is to hope
1308 that one of the retries will be successful but note that
1309 the DHCP timeout and retry process takes a longer than
1313 CONFIG_CDP_DEVICE_ID
1315 The device id used in CDP trigger frames.
1317 CONFIG_CDP_DEVICE_ID_PREFIX
1319 A two character string which is prefixed to the MAC address
1324 A printf format string which contains the ascii name of
1325 the port. Normally is set to "eth%d" which sets
1326 eth0 for the first Ethernet, eth1 for the second etc.
1328 CONFIG_CDP_CAPABILITIES
1330 A 32bit integer which indicates the device capabilities;
1331 0x00000010 for a normal host which does not forwards.
1335 An ascii string containing the version of the software.
1339 An ascii string containing the name of the platform.
1343 A 32bit integer sent on the trigger.
1345 CONFIG_CDP_POWER_CONSUMPTION
1347 A 16bit integer containing the power consumption of the
1348 device in .1 of milliwatts.
1350 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1352 A byte containing the id of the VLAN.
1354 - Status LED: CONFIG_STATUS_LED
1356 Several configurations allow to display the current
1357 status using a LED. For instance, the LED will blink
1358 fast while running U-Boot code, stop blinking as
1359 soon as a reply to a BOOTP request was received, and
1360 start blinking slow once the Linux kernel is running
1361 (supported by a status LED driver in the Linux
1362 kernel). Defining CONFIG_STATUS_LED enables this
1365 - CAN Support: CONFIG_CAN_DRIVER
1367 Defining CONFIG_CAN_DRIVER enables CAN driver support
1368 on those systems that support this (optional)
1369 feature, like the TQM8xxL modules.
1371 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1373 These enable I2C serial bus commands. Defining either of
1374 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1375 include the appropriate I2C driver for the selected CPU.
1377 This will allow you to use i2c commands at the u-boot
1378 command line (as long as you set CONFIG_CMD_I2C in
1379 CONFIG_COMMANDS) and communicate with i2c based realtime
1380 clock chips. See common/cmd_i2c.c for a description of the
1381 command line interface.
1383 CONFIG_HARD_I2C selects a hardware I2C controller.
1385 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1386 bit-banging) driver instead of CPM or similar hardware
1389 There are several other quantities that must also be
1390 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1392 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1393 to be the frequency (in Hz) at which you wish your i2c bus
1394 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1395 the CPU's i2c node address).
1397 Now, the u-boot i2c code for the mpc8xx
1398 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1399 and so its address should therefore be cleared to 0 (See,
1400 eg, MPC823e User's Manual p.16-473). So, set
1401 CONFIG_SYS_I2C_SLAVE to 0.
1403 CONFIG_SYS_I2C_INIT_MPC5XXX
1405 When a board is reset during an i2c bus transfer
1406 chips might think that the current transfer is still
1407 in progress. Reset the slave devices by sending start
1408 commands until the slave device responds.
1410 That's all that's required for CONFIG_HARD_I2C.
1412 If you use the software i2c interface (CONFIG_SOFT_I2C)
1413 then the following macros need to be defined (examples are
1414 from include/configs/lwmon.h):
1418 (Optional). Any commands necessary to enable the I2C
1419 controller or configure ports.
1421 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1425 (Only for MPC8260 CPU). The I/O port to use (the code
1426 assumes both bits are on the same port). Valid values
1427 are 0..3 for ports A..D.
1431 The code necessary to make the I2C data line active
1432 (driven). If the data line is open collector, this
1435 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1439 The code necessary to make the I2C data line tri-stated
1440 (inactive). If the data line is open collector, this
1443 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1447 Code that returns TRUE if the I2C data line is high,
1450 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1454 If <bit> is TRUE, sets the I2C data line high. If it
1455 is FALSE, it clears it (low).
1457 eg: #define I2C_SDA(bit) \
1458 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1459 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1463 If <bit> is TRUE, sets the I2C clock line high. If it
1464 is FALSE, it clears it (low).
1466 eg: #define I2C_SCL(bit) \
1467 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1468 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1472 This delay is invoked four times per clock cycle so this
1473 controls the rate of data transfer. The data rate thus
1474 is 1 / (I2C_DELAY * 4). Often defined to be something
1477 #define I2C_DELAY udelay(2)
1479 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1481 If your arch supports the generic GPIO framework (asm/gpio.h),
1482 then you may alternatively define the two GPIOs that are to be
1483 used as SCL / SDA. Any of the previous I2C_xxx macros will
1484 have GPIO-based defaults assigned to them as appropriate.
1486 You should define these to the GPIO value as given directly to
1487 the generic GPIO functions.
1489 CONFIG_SYS_I2C_INIT_BOARD
1491 When a board is reset during an i2c bus transfer
1492 chips might think that the current transfer is still
1493 in progress. On some boards it is possible to access
1494 the i2c SCLK line directly, either by using the
1495 processor pin as a GPIO or by having a second pin
1496 connected to the bus. If this option is defined a
1497 custom i2c_init_board() routine in boards/xxx/board.c
1498 is run early in the boot sequence.
1500 CONFIG_SYS_I2C_BOARD_LATE_INIT
1502 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1503 defined a custom i2c_board_late_init() routine in
1504 boards/xxx/board.c is run AFTER the operations in i2c_init()
1505 is completed. This callpoint can be used to unreset i2c bus
1506 using CPU i2c controller register accesses for CPUs whose i2c
1507 controller provide such a method. It is called at the end of
1508 i2c_init() to allow i2c_init operations to setup the i2c bus
1509 controller on the CPU (e.g. setting bus speed & slave address).
1511 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1513 This option enables configuration of bi_iic_fast[] flags
1514 in u-boot bd_info structure based on u-boot environment
1515 variable "i2cfast". (see also i2cfast)
1517 CONFIG_I2C_MULTI_BUS
1519 This option allows the use of multiple I2C buses, each of which
1520 must have a controller. At any point in time, only one bus is
1521 active. To switch to a different bus, use the 'i2c dev' command.
1522 Note that bus numbering is zero-based.
1524 CONFIG_SYS_I2C_NOPROBES
1526 This option specifies a list of I2C devices that will be skipped
1527 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1528 is set, specify a list of bus-device pairs. Otherwise, specify
1529 a 1D array of device addresses
1532 #undef CONFIG_I2C_MULTI_BUS
1533 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1535 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1537 #define CONFIG_I2C_MULTI_BUS
1538 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1540 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1542 CONFIG_SYS_SPD_BUS_NUM
1544 If defined, then this indicates the I2C bus number for DDR SPD.
1545 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1547 CONFIG_SYS_RTC_BUS_NUM
1549 If defined, then this indicates the I2C bus number for the RTC.
1550 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1552 CONFIG_SYS_DTT_BUS_NUM
1554 If defined, then this indicates the I2C bus number for the DTT.
1555 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1557 CONFIG_SYS_I2C_DTT_ADDR:
1559 If defined, specifies the I2C address of the DTT device.
1560 If not defined, then U-Boot uses predefined value for
1561 specified DTT device.
1565 Define this option if you want to use Freescale's I2C driver in
1566 drivers/i2c/fsl_i2c.c.
1570 Define this option if you have I2C devices reached over 1 .. n
1571 I2C Muxes like the pca9544a. This option addes a new I2C
1572 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1573 new I2C Bus to the existing I2C Busses. If you select the
1574 new Bus with "i2c dev", u-bbot sends first the commandos for
1575 the muxes to activate this new "bus".
1577 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1581 Adding a new I2C Bus reached over 2 pca9544a muxes
1582 The First mux with address 70 and channel 6
1583 The Second mux with address 71 and channel 4
1585 => i2c bus pca9544a:70:6:pca9544a:71:4
1587 Use the "i2c bus" command without parameter, to get a list
1588 of I2C Busses with muxes:
1591 Busses reached over muxes:
1593 reached over Mux(es):
1596 reached over Mux(es):
1601 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1602 u-boot sends First the Commando to the mux@70 to enable
1603 channel 6, and then the Commando to the mux@71 to enable
1606 After that, you can use the "normal" i2c commands as
1607 usual, to communicate with your I2C devices behind
1610 This option is actually implemented for the bitbanging
1611 algorithm in common/soft_i2c.c and for the Hardware I2C
1612 Bus on the MPC8260. But it should be not so difficult
1613 to add this option to other architectures.
1615 CONFIG_SOFT_I2C_READ_REPEATED_START
1617 defining this will force the i2c_read() function in
1618 the soft_i2c driver to perform an I2C repeated start
1619 between writing the address pointer and reading the
1620 data. If this define is omitted the default behaviour
1621 of doing a stop-start sequence will be used. Most I2C
1622 devices can use either method, but some require one or
1625 - SPI Support: CONFIG_SPI
1627 Enables SPI driver (so far only tested with
1628 SPI EEPROM, also an instance works with Crystal A/D and
1629 D/As on the SACSng board)
1633 Enables extended (16-bit) SPI EEPROM addressing.
1634 (symmetrical to CONFIG_I2C_X)
1638 Enables a software (bit-bang) SPI driver rather than
1639 using hardware support. This is a general purpose
1640 driver that only requires three general I/O port pins
1641 (two outputs, one input) to function. If this is
1642 defined, the board configuration must define several
1643 SPI configuration items (port pins to use, etc). For
1644 an example, see include/configs/sacsng.h.
1648 Enables a hardware SPI driver for general-purpose reads
1649 and writes. As with CONFIG_SOFT_SPI, the board configuration
1650 must define a list of chip-select function pointers.
1651 Currently supported on some MPC8xxx processors. For an
1652 example, see include/configs/mpc8349emds.h.
1656 Enables the driver for the SPI controllers on i.MX and MXC
1657 SoCs. Currently only i.MX31 is supported.
1659 - FPGA Support: CONFIG_FPGA
1661 Enables FPGA subsystem.
1663 CONFIG_FPGA_<vendor>
1665 Enables support for specific chip vendors.
1668 CONFIG_FPGA_<family>
1670 Enables support for FPGA family.
1671 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1675 Specify the number of FPGA devices to support.
1677 CONFIG_SYS_FPGA_PROG_FEEDBACK
1679 Enable printing of hash marks during FPGA configuration.
1681 CONFIG_SYS_FPGA_CHECK_BUSY
1683 Enable checks on FPGA configuration interface busy
1684 status by the configuration function. This option
1685 will require a board or device specific function to
1690 If defined, a function that provides delays in the FPGA
1691 configuration driver.
1693 CONFIG_SYS_FPGA_CHECK_CTRLC
1694 Allow Control-C to interrupt FPGA configuration
1696 CONFIG_SYS_FPGA_CHECK_ERROR
1698 Check for configuration errors during FPGA bitfile
1699 loading. For example, abort during Virtex II
1700 configuration if the INIT_B line goes low (which
1701 indicated a CRC error).
1703 CONFIG_SYS_FPGA_WAIT_INIT
1705 Maximum time to wait for the INIT_B line to deassert
1706 after PROB_B has been deasserted during a Virtex II
1707 FPGA configuration sequence. The default time is 500
1710 CONFIG_SYS_FPGA_WAIT_BUSY
1712 Maximum time to wait for BUSY to deassert during
1713 Virtex II FPGA configuration. The default is 5 ms.
1715 CONFIG_SYS_FPGA_WAIT_CONFIG
1717 Time to wait after FPGA configuration. The default is
1720 - Configuration Management:
1723 If defined, this string will be added to the U-Boot
1724 version information (U_BOOT_VERSION)
1726 - Vendor Parameter Protection:
1728 U-Boot considers the values of the environment
1729 variables "serial#" (Board Serial Number) and
1730 "ethaddr" (Ethernet Address) to be parameters that
1731 are set once by the board vendor / manufacturer, and
1732 protects these variables from casual modification by
1733 the user. Once set, these variables are read-only,
1734 and write or delete attempts are rejected. You can
1735 change this behaviour:
1737 If CONFIG_ENV_OVERWRITE is #defined in your config
1738 file, the write protection for vendor parameters is
1739 completely disabled. Anybody can change or delete
1742 Alternatively, if you #define _both_ CONFIG_ETHADDR
1743 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1744 Ethernet address is installed in the environment,
1745 which can be changed exactly ONCE by the user. [The
1746 serial# is unaffected by this, i. e. it remains
1752 Define this variable to enable the reservation of
1753 "protected RAM", i. e. RAM which is not overwritten
1754 by U-Boot. Define CONFIG_PRAM to hold the number of
1755 kB you want to reserve for pRAM. You can overwrite
1756 this default value by defining an environment
1757 variable "pram" to the number of kB you want to
1758 reserve. Note that the board info structure will
1759 still show the full amount of RAM. If pRAM is
1760 reserved, a new environment variable "mem" will
1761 automatically be defined to hold the amount of
1762 remaining RAM in a form that can be passed as boot
1763 argument to Linux, for instance like that:
1765 setenv bootargs ... mem=\${mem}
1768 This way you can tell Linux not to use this memory,
1769 either, which results in a memory region that will
1770 not be affected by reboots.
1772 *WARNING* If your board configuration uses automatic
1773 detection of the RAM size, you must make sure that
1774 this memory test is non-destructive. So far, the
1775 following board configurations are known to be
1778 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1779 HERMES, IP860, RPXlite, LWMON, LANTEC,
1780 PCU_E, FLAGADM, TQM8260
1785 Define this variable to stop the system in case of a
1786 fatal error, so that you have to reset it manually.
1787 This is probably NOT a good idea for an embedded
1788 system where you want the system to reboot
1789 automatically as fast as possible, but it may be
1790 useful during development since you can try to debug
1791 the conditions that lead to the situation.
1793 CONFIG_NET_RETRY_COUNT
1795 This variable defines the number of retries for
1796 network operations like ARP, RARP, TFTP, or BOOTP
1797 before giving up the operation. If not defined, a
1798 default value of 5 is used.
1802 Timeout waiting for an ARP reply in milliseconds.
1804 - Command Interpreter:
1805 CONFIG_AUTO_COMPLETE
1807 Enable auto completion of commands using TAB.
1809 Note that this feature has NOT been implemented yet
1810 for the "hush" shell.
1813 CONFIG_SYS_HUSH_PARSER
1815 Define this variable to enable the "hush" shell (from
1816 Busybox) as command line interpreter, thus enabling
1817 powerful command line syntax like
1818 if...then...else...fi conditionals or `&&' and '||'
1819 constructs ("shell scripts").
1821 If undefined, you get the old, much simpler behaviour
1822 with a somewhat smaller memory footprint.
1825 CONFIG_SYS_PROMPT_HUSH_PS2
1827 This defines the secondary prompt string, which is
1828 printed when the command interpreter needs more input
1829 to complete a command. Usually "> ".
1833 In the current implementation, the local variables
1834 space and global environment variables space are
1835 separated. Local variables are those you define by
1836 simply typing `name=value'. To access a local
1837 variable later on, you have write `$name' or
1838 `${name}'; to execute the contents of a variable
1839 directly type `$name' at the command prompt.
1841 Global environment variables are those you use
1842 setenv/printenv to work with. To run a command stored
1843 in such a variable, you need to use the run command,
1844 and you must not use the '$' sign to access them.
1846 To store commands and special characters in a
1847 variable, please use double quotation marks
1848 surrounding the whole text of the variable, instead
1849 of the backslashes before semicolons and special
1852 - Commandline Editing and History:
1853 CONFIG_CMDLINE_EDITING
1855 Enable editing and History functions for interactive
1856 commandline input operations
1858 - Default Environment:
1859 CONFIG_EXTRA_ENV_SETTINGS
1861 Define this to contain any number of null terminated
1862 strings (variable = value pairs) that will be part of
1863 the default environment compiled into the boot image.
1865 For example, place something like this in your
1866 board's config file:
1868 #define CONFIG_EXTRA_ENV_SETTINGS \
1872 Warning: This method is based on knowledge about the
1873 internal format how the environment is stored by the
1874 U-Boot code. This is NOT an official, exported
1875 interface! Although it is unlikely that this format
1876 will change soon, there is no guarantee either.
1877 You better know what you are doing here.
1879 Note: overly (ab)use of the default environment is
1880 discouraged. Make sure to check other ways to preset
1881 the environment like the "source" command or the
1884 - DataFlash Support:
1885 CONFIG_HAS_DATAFLASH
1887 Defining this option enables DataFlash features and
1888 allows to read/write in Dataflash via the standard
1891 - SystemACE Support:
1894 Adding this option adds support for Xilinx SystemACE
1895 chips attached via some sort of local bus. The address
1896 of the chip must also be defined in the
1897 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
1899 #define CONFIG_SYSTEMACE
1900 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
1902 When SystemACE support is added, the "ace" device type
1903 becomes available to the fat commands, i.e. fatls.
1905 - TFTP Fixed UDP Port:
1908 If this is defined, the environment variable tftpsrcp
1909 is used to supply the TFTP UDP source port value.
1910 If tftpsrcp isn't defined, the normal pseudo-random port
1911 number generator is used.
1913 Also, the environment variable tftpdstp is used to supply
1914 the TFTP UDP destination port value. If tftpdstp isn't
1915 defined, the normal port 69 is used.
1917 The purpose for tftpsrcp is to allow a TFTP server to
1918 blindly start the TFTP transfer using the pre-configured
1919 target IP address and UDP port. This has the effect of
1920 "punching through" the (Windows XP) firewall, allowing
1921 the remainder of the TFTP transfer to proceed normally.
1922 A better solution is to properly configure the firewall,
1923 but sometimes that is not allowed.
1925 - Show boot progress:
1926 CONFIG_SHOW_BOOT_PROGRESS
1928 Defining this option allows to add some board-
1929 specific code (calling a user-provided function
1930 "show_boot_progress(int)") that enables you to show
1931 the system's boot progress on some display (for
1932 example, some LED's) on your board. At the moment,
1933 the following checkpoints are implemented:
1935 Legacy uImage format:
1938 1 common/cmd_bootm.c before attempting to boot an image
1939 -1 common/cmd_bootm.c Image header has bad magic number
1940 2 common/cmd_bootm.c Image header has correct magic number
1941 -2 common/cmd_bootm.c Image header has bad checksum
1942 3 common/cmd_bootm.c Image header has correct checksum
1943 -3 common/cmd_bootm.c Image data has bad checksum
1944 4 common/cmd_bootm.c Image data has correct checksum
1945 -4 common/cmd_bootm.c Image is for unsupported architecture
1946 5 common/cmd_bootm.c Architecture check OK
1947 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
1948 6 common/cmd_bootm.c Image Type check OK
1949 -6 common/cmd_bootm.c gunzip uncompression error
1950 -7 common/cmd_bootm.c Unimplemented compression type
1951 7 common/cmd_bootm.c Uncompression OK
1952 8 common/cmd_bootm.c No uncompress/copy overwrite error
1953 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1955 9 common/image.c Start initial ramdisk verification
1956 -10 common/image.c Ramdisk header has bad magic number
1957 -11 common/image.c Ramdisk header has bad checksum
1958 10 common/image.c Ramdisk header is OK
1959 -12 common/image.c Ramdisk data has bad checksum
1960 11 common/image.c Ramdisk data has correct checksum
1961 12 common/image.c Ramdisk verification complete, start loading
1962 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
1963 13 common/image.c Start multifile image verification
1964 14 common/image.c No initial ramdisk, no multifile, continue.
1966 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
1968 -30 arch/powerpc/lib/board.c Fatal error, hang the system
1969 -31 post/post.c POST test failed, detected by post_output_backlog()
1970 -32 post/post.c POST test failed, detected by post_run_single()
1972 34 common/cmd_doc.c before loading a Image from a DOC device
1973 -35 common/cmd_doc.c Bad usage of "doc" command
1974 35 common/cmd_doc.c correct usage of "doc" command
1975 -36 common/cmd_doc.c No boot device
1976 36 common/cmd_doc.c correct boot device
1977 -37 common/cmd_doc.c Unknown Chip ID on boot device
1978 37 common/cmd_doc.c correct chip ID found, device available
1979 -38 common/cmd_doc.c Read Error on boot device
1980 38 common/cmd_doc.c reading Image header from DOC device OK
1981 -39 common/cmd_doc.c Image header has bad magic number
1982 39 common/cmd_doc.c Image header has correct magic number
1983 -40 common/cmd_doc.c Error reading Image from DOC device
1984 40 common/cmd_doc.c Image header has correct magic number
1985 41 common/cmd_ide.c before loading a Image from a IDE device
1986 -42 common/cmd_ide.c Bad usage of "ide" command
1987 42 common/cmd_ide.c correct usage of "ide" command
1988 -43 common/cmd_ide.c No boot device
1989 43 common/cmd_ide.c boot device found
1990 -44 common/cmd_ide.c Device not available
1991 44 common/cmd_ide.c Device available
1992 -45 common/cmd_ide.c wrong partition selected
1993 45 common/cmd_ide.c partition selected
1994 -46 common/cmd_ide.c Unknown partition table
1995 46 common/cmd_ide.c valid partition table found
1996 -47 common/cmd_ide.c Invalid partition type
1997 47 common/cmd_ide.c correct partition type
1998 -48 common/cmd_ide.c Error reading Image Header on boot device
1999 48 common/cmd_ide.c reading Image Header from IDE device OK
2000 -49 common/cmd_ide.c Image header has bad magic number
2001 49 common/cmd_ide.c Image header has correct magic number
2002 -50 common/cmd_ide.c Image header has bad checksum
2003 50 common/cmd_ide.c Image header has correct checksum
2004 -51 common/cmd_ide.c Error reading Image from IDE device
2005 51 common/cmd_ide.c reading Image from IDE device OK
2006 52 common/cmd_nand.c before loading a Image from a NAND device
2007 -53 common/cmd_nand.c Bad usage of "nand" command
2008 53 common/cmd_nand.c correct usage of "nand" command
2009 -54 common/cmd_nand.c No boot device
2010 54 common/cmd_nand.c boot device found
2011 -55 common/cmd_nand.c Unknown Chip ID on boot device
2012 55 common/cmd_nand.c correct chip ID found, device available
2013 -56 common/cmd_nand.c Error reading Image Header on boot device
2014 56 common/cmd_nand.c reading Image Header from NAND device OK
2015 -57 common/cmd_nand.c Image header has bad magic number
2016 57 common/cmd_nand.c Image header has correct magic number
2017 -58 common/cmd_nand.c Error reading Image from NAND device
2018 58 common/cmd_nand.c reading Image from NAND device OK
2020 -60 common/env_common.c Environment has a bad CRC, using default
2022 64 net/eth.c starting with Ethernet configuration.
2023 -64 net/eth.c no Ethernet found.
2024 65 net/eth.c Ethernet found.
2026 -80 common/cmd_net.c usage wrong
2027 80 common/cmd_net.c before calling NetLoop()
2028 -81 common/cmd_net.c some error in NetLoop() occurred
2029 81 common/cmd_net.c NetLoop() back without error
2030 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2031 82 common/cmd_net.c trying automatic boot
2032 83 common/cmd_net.c running "source" command
2033 -83 common/cmd_net.c some error in automatic boot or "source" command
2034 84 common/cmd_net.c end without errors
2039 100 common/cmd_bootm.c Kernel FIT Image has correct format
2040 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2041 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2042 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2043 102 common/cmd_bootm.c Kernel unit name specified
2044 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2045 103 common/cmd_bootm.c Found configuration node
2046 104 common/cmd_bootm.c Got kernel subimage node offset
2047 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2048 105 common/cmd_bootm.c Kernel subimage hash verification OK
2049 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2050 106 common/cmd_bootm.c Architecture check OK
2051 -106 common/cmd_bootm.c Kernel subimage has wrong type
2052 107 common/cmd_bootm.c Kernel subimage type OK
2053 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2054 108 common/cmd_bootm.c Got kernel subimage data/size
2055 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2056 -109 common/cmd_bootm.c Can't get kernel subimage type
2057 -110 common/cmd_bootm.c Can't get kernel subimage comp
2058 -111 common/cmd_bootm.c Can't get kernel subimage os
2059 -112 common/cmd_bootm.c Can't get kernel subimage load address
2060 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2062 120 common/image.c Start initial ramdisk verification
2063 -120 common/image.c Ramdisk FIT image has incorrect format
2064 121 common/image.c Ramdisk FIT image has correct format
2065 122 common/image.c No ramdisk subimage unit name, using configuration
2066 -122 common/image.c Can't get configuration for ramdisk subimage
2067 123 common/image.c Ramdisk unit name specified
2068 -124 common/image.c Can't get ramdisk subimage node offset
2069 125 common/image.c Got ramdisk subimage node offset
2070 -125 common/image.c Ramdisk subimage hash verification failed
2071 126 common/image.c Ramdisk subimage hash verification OK
2072 -126 common/image.c Ramdisk subimage for unsupported architecture
2073 127 common/image.c Architecture check OK
2074 -127 common/image.c Can't get ramdisk subimage data/size
2075 128 common/image.c Got ramdisk subimage data/size
2076 129 common/image.c Can't get ramdisk load address
2077 -129 common/image.c Got ramdisk load address
2079 -130 common/cmd_doc.c Incorrect FIT image format
2080 131 common/cmd_doc.c FIT image format OK
2082 -140 common/cmd_ide.c Incorrect FIT image format
2083 141 common/cmd_ide.c FIT image format OK
2085 -150 common/cmd_nand.c Incorrect FIT image format
2086 151 common/cmd_nand.c FIT image format OK
2088 - Automatic software updates via TFTP server
2090 CONFIG_UPDATE_TFTP_CNT_MAX
2091 CONFIG_UPDATE_TFTP_MSEC_MAX
2093 These options enable and control the auto-update feature;
2094 for a more detailed description refer to doc/README.update.
2096 - MTD Support (mtdparts command, UBI support)
2099 Adds the MTD device infrastructure from the Linux kernel.
2100 Needed for mtdparts command support.
2102 CONFIG_MTD_PARTITIONS
2104 Adds the MTD partitioning infrastructure from the Linux
2105 kernel. Needed for UBI support.
2111 [so far only for SMDK2400 and TRAB boards]
2113 - Modem support enable:
2114 CONFIG_MODEM_SUPPORT
2116 - RTS/CTS Flow control enable:
2119 - Modem debug support:
2120 CONFIG_MODEM_SUPPORT_DEBUG
2122 Enables debugging stuff (char screen[1024], dbg())
2123 for modem support. Useful only with BDI2000.
2125 - Interrupt support (PPC):
2127 There are common interrupt_init() and timer_interrupt()
2128 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2129 for CPU specific initialization. interrupt_init_cpu()
2130 should set decrementer_count to appropriate value. If
2131 CPU resets decrementer automatically after interrupt
2132 (ppc4xx) it should set decrementer_count to zero.
2133 timer_interrupt() calls timer_interrupt_cpu() for CPU
2134 specific handling. If board has watchdog / status_led
2135 / other_activity_monitor it works automatically from
2136 general timer_interrupt().
2140 In the target system modem support is enabled when a
2141 specific key (key combination) is pressed during
2142 power-on. Otherwise U-Boot will boot normally
2143 (autoboot). The key_pressed() function is called from
2144 board_init(). Currently key_pressed() is a dummy
2145 function, returning 1 and thus enabling modem
2148 If there are no modem init strings in the
2149 environment, U-Boot proceed to autoboot; the
2150 previous output (banner, info printfs) will be
2153 See also: doc/README.Modem
2156 Configuration Settings:
2157 -----------------------
2159 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2160 undefine this when you're short of memory.
2162 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2163 width of the commands listed in the 'help' command output.
2165 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2166 prompt for user input.
2168 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2170 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2172 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2174 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2175 the application (usually a Linux kernel) when it is
2178 - CONFIG_SYS_BAUDRATE_TABLE:
2179 List of legal baudrate settings for this board.
2181 - CONFIG_SYS_CONSOLE_INFO_QUIET
2182 Suppress display of console information at boot.
2184 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2185 If the board specific function
2186 extern int overwrite_console (void);
2187 returns 1, the stdin, stderr and stdout are switched to the
2188 serial port, else the settings in the environment are used.
2190 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2191 Enable the call to overwrite_console().
2193 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2194 Enable overwrite of previous console environment settings.
2196 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2197 Begin and End addresses of the area used by the
2200 - CONFIG_SYS_ALT_MEMTEST:
2201 Enable an alternate, more extensive memory test.
2203 - CONFIG_SYS_MEMTEST_SCRATCH:
2204 Scratch address used by the alternate memory test
2205 You only need to set this if address zero isn't writeable
2207 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2208 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2209 this specified memory area will get subtracted from the top
2210 (end) of RAM and won't get "touched" at all by U-Boot. By
2211 fixing up gd->ram_size the Linux kernel should gets passed
2212 the now "corrected" memory size and won't touch it either.
2213 This should work for arch/ppc and arch/powerpc. Only Linux
2214 board ports in arch/powerpc with bootwrapper support that
2215 recalculate the memory size from the SDRAM controller setup
2216 will have to get fixed in Linux additionally.
2218 This option can be used as a workaround for the 440EPx/GRx
2219 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2222 WARNING: Please make sure that this value is a multiple of
2223 the Linux page size (normally 4k). If this is not the case,
2224 then the end address of the Linux memory will be located at a
2225 non page size aligned address and this could cause major
2228 - CONFIG_SYS_TFTP_LOADADDR:
2229 Default load address for network file downloads
2231 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2232 Enable temporary baudrate change while serial download
2234 - CONFIG_SYS_SDRAM_BASE:
2235 Physical start address of SDRAM. _Must_ be 0 here.
2237 - CONFIG_SYS_MBIO_BASE:
2238 Physical start address of Motherboard I/O (if using a
2241 - CONFIG_SYS_FLASH_BASE:
2242 Physical start address of Flash memory.
2244 - CONFIG_SYS_MONITOR_BASE:
2245 Physical start address of boot monitor code (set by
2246 make config files to be same as the text base address
2247 (TEXT_BASE) used when linking) - same as
2248 CONFIG_SYS_FLASH_BASE when booting from flash.
2250 - CONFIG_SYS_MONITOR_LEN:
2251 Size of memory reserved for monitor code, used to
2252 determine _at_compile_time_ (!) if the environment is
2253 embedded within the U-Boot image, or in a separate
2256 - CONFIG_SYS_MALLOC_LEN:
2257 Size of DRAM reserved for malloc() use.
2259 - CONFIG_SYS_BOOTM_LEN:
2260 Normally compressed uImages are limited to an
2261 uncompressed size of 8 MBytes. If this is not enough,
2262 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2263 to adjust this setting to your needs.
2265 - CONFIG_SYS_BOOTMAPSZ:
2266 Maximum size of memory mapped by the startup code of
2267 the Linux kernel; all data that must be processed by
2268 the Linux kernel (bd_info, boot arguments, FDT blob if
2269 used) must be put below this limit, unless "bootm_low"
2270 enviroment variable is defined and non-zero. In such case
2271 all data for the Linux kernel must be between "bootm_low"
2272 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.
2274 - CONFIG_SYS_MAX_FLASH_BANKS:
2275 Max number of Flash memory banks
2277 - CONFIG_SYS_MAX_FLASH_SECT:
2278 Max number of sectors on a Flash chip
2280 - CONFIG_SYS_FLASH_ERASE_TOUT:
2281 Timeout for Flash erase operations (in ms)
2283 - CONFIG_SYS_FLASH_WRITE_TOUT:
2284 Timeout for Flash write operations (in ms)
2286 - CONFIG_SYS_FLASH_LOCK_TOUT
2287 Timeout for Flash set sector lock bit operation (in ms)
2289 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2290 Timeout for Flash clear lock bits operation (in ms)
2292 - CONFIG_SYS_FLASH_PROTECTION
2293 If defined, hardware flash sectors protection is used
2294 instead of U-Boot software protection.
2296 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2298 Enable TFTP transfers directly to flash memory;
2299 without this option such a download has to be
2300 performed in two steps: (1) download to RAM, and (2)
2301 copy from RAM to flash.
2303 The two-step approach is usually more reliable, since
2304 you can check if the download worked before you erase
2305 the flash, but in some situations (when system RAM is
2306 too limited to allow for a temporary copy of the
2307 downloaded image) this option may be very useful.
2309 - CONFIG_SYS_FLASH_CFI:
2310 Define if the flash driver uses extra elements in the
2311 common flash structure for storing flash geometry.
2313 - CONFIG_FLASH_CFI_DRIVER
2314 This option also enables the building of the cfi_flash driver
2315 in the drivers directory
2317 - CONFIG_FLASH_CFI_MTD
2318 This option enables the building of the cfi_mtd driver
2319 in the drivers directory. The driver exports CFI flash
2322 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2323 Use buffered writes to flash.
2325 - CONFIG_FLASH_SPANSION_S29WS_N
2326 s29ws-n MirrorBit flash has non-standard addresses for buffered
2329 - CONFIG_SYS_FLASH_QUIET_TEST
2330 If this option is defined, the common CFI flash doesn't
2331 print it's warning upon not recognized FLASH banks. This
2332 is useful, if some of the configured banks are only
2333 optionally available.
2335 - CONFIG_FLASH_SHOW_PROGRESS
2336 If defined (must be an integer), print out countdown
2337 digits and dots. Recommended value: 45 (9..1) for 80
2338 column displays, 15 (3..1) for 40 column displays.
2340 - CONFIG_SYS_RX_ETH_BUFFER:
2341 Defines the number of Ethernet receive buffers. On some
2342 Ethernet controllers it is recommended to set this value
2343 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2344 buffers can be full shortly after enabling the interface
2345 on high Ethernet traffic.
2346 Defaults to 4 if not defined.
2348 - CONFIG_ENV_MAX_ENTRIES
2350 Maximum number of entries in the hash table that is used
2351 internally to store the environment settings. The default
2352 setting is supposed to be generous and should work in most
2353 cases. This setting can be used to tune behaviour; see
2354 lib/hashtable.c for details.
2356 The following definitions that deal with the placement and management
2357 of environment data (variable area); in general, we support the
2358 following configurations:
2360 - CONFIG_ENV_IS_IN_FLASH:
2362 Define this if the environment is in flash memory.
2364 a) The environment occupies one whole flash sector, which is
2365 "embedded" in the text segment with the U-Boot code. This
2366 happens usually with "bottom boot sector" or "top boot
2367 sector" type flash chips, which have several smaller
2368 sectors at the start or the end. For instance, such a
2369 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2370 such a case you would place the environment in one of the
2371 4 kB sectors - with U-Boot code before and after it. With
2372 "top boot sector" type flash chips, you would put the
2373 environment in one of the last sectors, leaving a gap
2374 between U-Boot and the environment.
2376 - CONFIG_ENV_OFFSET:
2378 Offset of environment data (variable area) to the
2379 beginning of flash memory; for instance, with bottom boot
2380 type flash chips the second sector can be used: the offset
2381 for this sector is given here.
2383 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2387 This is just another way to specify the start address of
2388 the flash sector containing the environment (instead of
2391 - CONFIG_ENV_SECT_SIZE:
2393 Size of the sector containing the environment.
2396 b) Sometimes flash chips have few, equal sized, BIG sectors.
2397 In such a case you don't want to spend a whole sector for
2402 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2403 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2404 of this flash sector for the environment. This saves
2405 memory for the RAM copy of the environment.
2407 It may also save flash memory if you decide to use this
2408 when your environment is "embedded" within U-Boot code,
2409 since then the remainder of the flash sector could be used
2410 for U-Boot code. It should be pointed out that this is
2411 STRONGLY DISCOURAGED from a robustness point of view:
2412 updating the environment in flash makes it always
2413 necessary to erase the WHOLE sector. If something goes
2414 wrong before the contents has been restored from a copy in
2415 RAM, your target system will be dead.
2417 - CONFIG_ENV_ADDR_REDUND
2418 CONFIG_ENV_SIZE_REDUND
2420 These settings describe a second storage area used to hold
2421 a redundant copy of the environment data, so that there is
2422 a valid backup copy in case there is a power failure during
2423 a "saveenv" operation.
2425 BE CAREFUL! Any changes to the flash layout, and some changes to the
2426 source code will make it necessary to adapt <board>/u-boot.lds*
2430 - CONFIG_ENV_IS_IN_NVRAM:
2432 Define this if you have some non-volatile memory device
2433 (NVRAM, battery buffered SRAM) which you want to use for the
2439 These two #defines are used to determine the memory area you
2440 want to use for environment. It is assumed that this memory
2441 can just be read and written to, without any special
2444 BE CAREFUL! The first access to the environment happens quite early
2445 in U-Boot initalization (when we try to get the setting of for the
2446 console baudrate). You *MUST* have mapped your NVRAM area then, or
2449 Please note that even with NVRAM we still use a copy of the
2450 environment in RAM: we could work on NVRAM directly, but we want to
2451 keep settings there always unmodified except somebody uses "saveenv"
2452 to save the current settings.
2455 - CONFIG_ENV_IS_IN_EEPROM:
2457 Use this if you have an EEPROM or similar serial access
2458 device and a driver for it.
2460 - CONFIG_ENV_OFFSET:
2463 These two #defines specify the offset and size of the
2464 environment area within the total memory of your EEPROM.
2466 - CONFIG_SYS_I2C_EEPROM_ADDR:
2467 If defined, specified the chip address of the EEPROM device.
2468 The default address is zero.
2470 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2471 If defined, the number of bits used to address bytes in a
2472 single page in the EEPROM device. A 64 byte page, for example
2473 would require six bits.
2475 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2476 If defined, the number of milliseconds to delay between
2477 page writes. The default is zero milliseconds.
2479 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2480 The length in bytes of the EEPROM memory array address. Note
2481 that this is NOT the chip address length!
2483 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2484 EEPROM chips that implement "address overflow" are ones
2485 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2486 address and the extra bits end up in the "chip address" bit
2487 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2490 Note that we consider the length of the address field to
2491 still be one byte because the extra address bits are hidden
2492 in the chip address.
2494 - CONFIG_SYS_EEPROM_SIZE:
2495 The size in bytes of the EEPROM device.
2497 - CONFIG_ENV_EEPROM_IS_ON_I2C
2498 define this, if you have I2C and SPI activated, and your
2499 EEPROM, which holds the environment, is on the I2C bus.
2501 - CONFIG_I2C_ENV_EEPROM_BUS
2502 if you have an Environment on an EEPROM reached over
2503 I2C muxes, you can define here, how to reach this
2504 EEPROM. For example:
2506 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2508 EEPROM which holds the environment, is reached over
2509 a pca9547 i2c mux with address 0x70, channel 3.
2511 - CONFIG_ENV_IS_IN_DATAFLASH:
2513 Define this if you have a DataFlash memory device which you
2514 want to use for the environment.
2516 - CONFIG_ENV_OFFSET:
2520 These three #defines specify the offset and size of the
2521 environment area within the total memory of your DataFlash placed
2522 at the specified address.
2524 - CONFIG_ENV_IS_IN_NAND:
2526 Define this if you have a NAND device which you want to use
2527 for the environment.
2529 - CONFIG_ENV_OFFSET:
2532 These two #defines specify the offset and size of the environment
2533 area within the first NAND device.
2535 - CONFIG_ENV_OFFSET_REDUND
2537 This setting describes a second storage area of CONFIG_ENV_SIZE
2538 size used to hold a redundant copy of the environment data,
2539 so that there is a valid backup copy in case there is a
2540 power failure during a "saveenv" operation.
2542 Note: CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND must be aligned
2543 to a block boundary, and CONFIG_ENV_SIZE must be a multiple of
2544 the NAND devices block size.
2546 - CONFIG_NAND_ENV_DST
2548 Defines address in RAM to which the nand_spl code should copy the
2549 environment. If redundant environment is used, it will be copied to
2550 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2552 - CONFIG_SYS_SPI_INIT_OFFSET
2554 Defines offset to the initial SPI buffer area in DPRAM. The
2555 area is used at an early stage (ROM part) if the environment
2556 is configured to reside in the SPI EEPROM: We need a 520 byte
2557 scratch DPRAM area. It is used between the two initialization
2558 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2559 to be a good choice since it makes it far enough from the
2560 start of the data area as well as from the stack pointer.
2562 Please note that the environment is read-only until the monitor
2563 has been relocated to RAM and a RAM copy of the environment has been
2564 created; also, when using EEPROM you will have to use getenv_f()
2565 until then to read environment variables.
2567 The environment is protected by a CRC32 checksum. Before the monitor
2568 is relocated into RAM, as a result of a bad CRC you will be working
2569 with the compiled-in default environment - *silently*!!! [This is
2570 necessary, because the first environment variable we need is the
2571 "baudrate" setting for the console - if we have a bad CRC, we don't
2572 have any device yet where we could complain.]
2574 Note: once the monitor has been relocated, then it will complain if
2575 the default environment is used; a new CRC is computed as soon as you
2576 use the "saveenv" command to store a valid environment.
2578 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2579 Echo the inverted Ethernet link state to the fault LED.
2581 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2582 also needs to be defined.
2584 - CONFIG_SYS_FAULT_MII_ADDR:
2585 MII address of the PHY to check for the Ethernet link state.
2587 - CONFIG_NS16550_MIN_FUNCTIONS:
2588 Define this if you desire to only have use of the NS16550_init
2589 and NS16550_putc functions for the serial driver located at
2590 drivers/serial/ns16550.c. This option is useful for saving
2591 space for already greatly restricted images, including but not
2592 limited to NAND_SPL configurations.
2594 Low Level (hardware related) configuration options:
2595 ---------------------------------------------------
2597 - CONFIG_SYS_CACHELINE_SIZE:
2598 Cache Line Size of the CPU.
2600 - CONFIG_SYS_DEFAULT_IMMR:
2601 Default address of the IMMR after system reset.
2603 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2604 and RPXsuper) to be able to adjust the position of
2605 the IMMR register after a reset.
2607 - Floppy Disk Support:
2608 CONFIG_SYS_FDC_DRIVE_NUMBER
2610 the default drive number (default value 0)
2612 CONFIG_SYS_ISA_IO_STRIDE
2614 defines the spacing between FDC chipset registers
2617 CONFIG_SYS_ISA_IO_OFFSET
2619 defines the offset of register from address. It
2620 depends on which part of the data bus is connected to
2621 the FDC chipset. (default value 0)
2623 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2624 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2627 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2628 fdc_hw_init() is called at the beginning of the FDC
2629 setup. fdc_hw_init() must be provided by the board
2630 source code. It is used to make hardware dependant
2633 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2634 DO NOT CHANGE unless you know exactly what you're
2635 doing! (11-4) [MPC8xx/82xx systems only]
2637 - CONFIG_SYS_INIT_RAM_ADDR:
2639 Start address of memory area that can be used for
2640 initial data and stack; please note that this must be
2641 writable memory that is working WITHOUT special
2642 initialization, i. e. you CANNOT use normal RAM which
2643 will become available only after programming the
2644 memory controller and running certain initialization
2647 U-Boot uses the following memory types:
2648 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2649 - MPC824X: data cache
2650 - PPC4xx: data cache
2652 - CONFIG_SYS_GBL_DATA_OFFSET:
2654 Offset of the initial data structure in the memory
2655 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2656 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2657 data is located at the end of the available space
2658 (sometimes written as (CONFIG_SYS_INIT_RAM_END -
2659 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2660 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2661 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2664 On the MPC824X (or other systems that use the data
2665 cache for initial memory) the address chosen for
2666 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2667 point to an otherwise UNUSED address space between
2668 the top of RAM and the start of the PCI space.
2670 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2672 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2674 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2676 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2678 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2680 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2682 - CONFIG_SYS_OR_TIMING_SDRAM:
2685 - CONFIG_SYS_MAMR_PTA:
2686 periodic timer for refresh
2688 - CONFIG_SYS_DER: Debug Event Register (37-47)
2690 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2691 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2692 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2693 CONFIG_SYS_BR1_PRELIM:
2694 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2696 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2697 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2698 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2699 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2701 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2702 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2703 Machine Mode Register and Memory Periodic Timer
2704 Prescaler definitions (SDRAM timing)
2706 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2707 enable I2C microcode relocation patch (MPC8xx);
2708 define relocation offset in DPRAM [DSP2]
2710 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2711 enable SMC microcode relocation patch (MPC8xx);
2712 define relocation offset in DPRAM [SMC1]
2714 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2715 enable SPI microcode relocation patch (MPC8xx);
2716 define relocation offset in DPRAM [SCC4]
2718 - CONFIG_SYS_USE_OSCCLK:
2719 Use OSCM clock mode on MBX8xx board. Be careful,
2720 wrong setting might damage your board. Read
2721 doc/README.MBX before setting this variable!
2723 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2724 Offset of the bootmode word in DPRAM used by post
2725 (Power On Self Tests). This definition overrides
2726 #define'd default value in commproc.h resp.
2729 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2730 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2731 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2732 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2733 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2734 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2735 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2736 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2737 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2739 - CONFIG_PCI_DISABLE_PCIE:
2740 Disable PCI-Express on systems where it is supported but not
2744 Get DDR timing information from an I2C EEPROM. Common
2745 with pluggable memory modules such as SODIMMs
2748 I2C address of the SPD EEPROM
2750 - CONFIG_SYS_SPD_BUS_NUM
2751 If SPD EEPROM is on an I2C bus other than the first
2752 one, specify here. Note that the value must resolve
2753 to something your driver can deal with.
2755 - CONFIG_SYS_83XX_DDR_USES_CS0
2756 Only for 83xx systems. If specified, then DDR should
2757 be configured using CS0 and CS1 instead of CS2 and CS3.
2759 - CONFIG_ETHER_ON_FEC[12]
2760 Define to enable FEC[12] on a 8xx series processor.
2762 - CONFIG_FEC[12]_PHY
2763 Define to the hardcoded PHY address which corresponds
2764 to the given FEC; i. e.
2765 #define CONFIG_FEC1_PHY 4
2766 means that the PHY with address 4 is connected to FEC1
2768 When set to -1, means to probe for first available.
2770 - CONFIG_FEC[12]_PHY_NORXERR
2771 The PHY does not have a RXERR line (RMII only).
2772 (so program the FEC to ignore it).
2775 Enable RMII mode for all FECs.
2776 Note that this is a global option, we can't
2777 have one FEC in standard MII mode and another in RMII mode.
2779 - CONFIG_CRC32_VERIFY
2780 Add a verify option to the crc32 command.
2783 => crc32 -v <address> <count> <crc32>
2785 Where address/count indicate a memory area
2786 and crc32 is the correct crc32 which the
2790 Add the "loopw" memory command. This only takes effect if
2791 the memory commands are activated globally (CONFIG_CMD_MEM).
2794 Add the "mdc" and "mwc" memory commands. These are cyclic
2799 This command will print 4 bytes (10,11,12,13) each 500 ms.
2801 => mwc.l 100 12345678 10
2802 This command will write 12345678 to address 100 all 10 ms.
2804 This only takes effect if the memory commands are activated
2805 globally (CONFIG_CMD_MEM).
2807 - CONFIG_SKIP_LOWLEVEL_INIT
2808 - CONFIG_SKIP_RELOCATE_UBOOT
2810 [ARM only] If these variables are defined, then
2811 certain low level initializations (like setting up
2812 the memory controller) are omitted and/or U-Boot does
2813 not relocate itself into RAM.
2814 Normally these variables MUST NOT be defined. The
2815 only exception is when U-Boot is loaded (to RAM) by
2816 some other boot loader or by a debugger which
2817 performs these initializations itself.
2821 Modifies the behaviour of start.S when compiling a loader
2822 that is executed before the actual U-Boot. E.g. when
2823 compiling a NAND SPL.
2825 Building the Software:
2826 ======================
2828 Building U-Boot has been tested in several native build environments
2829 and in many different cross environments. Of course we cannot support
2830 all possibly existing versions of cross development tools in all
2831 (potentially obsolete) versions. In case of tool chain problems we
2832 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
2833 which is extensively used to build and test U-Boot.
2835 If you are not using a native environment, it is assumed that you
2836 have GNU cross compiling tools available in your path. In this case,
2837 you must set the environment variable CROSS_COMPILE in your shell.
2838 Note that no changes to the Makefile or any other source files are
2839 necessary. For example using the ELDK on a 4xx CPU, please enter:
2841 $ CROSS_COMPILE=ppc_4xx-
2842 $ export CROSS_COMPILE
2844 Note: If you wish to generate Windows versions of the utilities in
2845 the tools directory you can use the MinGW toolchain
2846 (http://www.mingw.org). Set your HOST tools to the MinGW
2847 toolchain and execute 'make tools'. For example:
2849 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
2851 Binaries such as tools/mkimage.exe will be created which can
2852 be executed on computers running Windows.
2854 U-Boot is intended to be simple to build. After installing the
2855 sources you must configure U-Boot for one specific board type. This
2860 where "NAME_config" is the name of one of the existing configu-
2861 rations; see the main Makefile for supported names.
2863 Note: for some board special configuration names may exist; check if
2864 additional information is available from the board vendor; for
2865 instance, the TQM823L systems are available without (standard)
2866 or with LCD support. You can select such additional "features"
2867 when choosing the configuration, i. e.
2870 - will configure for a plain TQM823L, i. e. no LCD support
2872 make TQM823L_LCD_config
2873 - will configure for a TQM823L with U-Boot console on LCD
2878 Finally, type "make all", and you should get some working U-Boot
2879 images ready for download to / installation on your system:
2881 - "u-boot.bin" is a raw binary image
2882 - "u-boot" is an image in ELF binary format
2883 - "u-boot.srec" is in Motorola S-Record format
2885 By default the build is performed locally and the objects are saved
2886 in the source directory. One of the two methods can be used to change
2887 this behavior and build U-Boot to some external directory:
2889 1. Add O= to the make command line invocations:
2891 make O=/tmp/build distclean
2892 make O=/tmp/build NAME_config
2893 make O=/tmp/build all
2895 2. Set environment variable BUILD_DIR to point to the desired location:
2897 export BUILD_DIR=/tmp/build
2902 Note that the command line "O=" setting overrides the BUILD_DIR environment
2906 Please be aware that the Makefiles assume you are using GNU make, so
2907 for instance on NetBSD you might need to use "gmake" instead of
2911 If the system board that you have is not listed, then you will need
2912 to port U-Boot to your hardware platform. To do this, follow these
2915 1. Add a new configuration option for your board to the toplevel
2916 "Makefile" and to the "MAKEALL" script, using the existing
2917 entries as examples. Note that here and at many other places
2918 boards and other names are listed in alphabetical sort order. Please
2920 2. Create a new directory to hold your board specific code. Add any
2921 files you need. In your board directory, you will need at least
2922 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2923 3. Create a new configuration file "include/configs/<board>.h" for
2925 3. If you're porting U-Boot to a new CPU, then also create a new
2926 directory to hold your CPU specific code. Add any files you need.
2927 4. Run "make <board>_config" with your new name.
2928 5. Type "make", and you should get a working "u-boot.srec" file
2929 to be installed on your target system.
2930 6. Debug and solve any problems that might arise.
2931 [Of course, this last step is much harder than it sounds.]
2934 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2935 ==============================================================
2937 If you have modified U-Boot sources (for instance added a new board
2938 or support for new devices, a new CPU, etc.) you are expected to
2939 provide feedback to the other developers. The feedback normally takes
2940 the form of a "patch", i. e. a context diff against a certain (latest
2941 official or latest in the git repository) version of U-Boot sources.
2943 But before you submit such a patch, please verify that your modifi-
2944 cation did not break existing code. At least make sure that *ALL* of
2945 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2946 just run the "MAKEALL" script, which will configure and build U-Boot
2947 for ALL supported system. Be warned, this will take a while. You can
2948 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2949 environment variable to the script, i. e. to use the ELDK cross tools
2952 CROSS_COMPILE=ppc_8xx- MAKEALL
2954 or to build on a native PowerPC system you can type
2956 CROSS_COMPILE=' ' MAKEALL
2958 When using the MAKEALL script, the default behaviour is to build
2959 U-Boot in the source directory. This location can be changed by
2960 setting the BUILD_DIR environment variable. Also, for each target
2961 built, the MAKEALL script saves two log files (<target>.ERR and
2962 <target>.MAKEALL) in the <source dir>/LOG directory. This default
2963 location can be changed by setting the MAKEALL_LOGDIR environment
2964 variable. For example:
2966 export BUILD_DIR=/tmp/build
2967 export MAKEALL_LOGDIR=/tmp/log
2968 CROSS_COMPILE=ppc_8xx- MAKEALL
2970 With the above settings build objects are saved in the /tmp/build,
2971 log files are saved in the /tmp/log and the source tree remains clean
2972 during the whole build process.
2975 See also "U-Boot Porting Guide" below.
2978 Monitor Commands - Overview:
2979 ============================
2981 go - start application at address 'addr'
2982 run - run commands in an environment variable
2983 bootm - boot application image from memory
2984 bootp - boot image via network using BootP/TFTP protocol
2985 tftpboot- boot image via network using TFTP protocol
2986 and env variables "ipaddr" and "serverip"
2987 (and eventually "gatewayip")
2988 rarpboot- boot image via network using RARP/TFTP protocol
2989 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2990 loads - load S-Record file over serial line
2991 loadb - load binary file over serial line (kermit mode)
2993 mm - memory modify (auto-incrementing)
2994 nm - memory modify (constant address)
2995 mw - memory write (fill)
2997 cmp - memory compare
2998 crc32 - checksum calculation
2999 i2c - I2C sub-system
3000 sspi - SPI utility commands
3001 base - print or set address offset
3002 printenv- print environment variables
3003 setenv - set environment variables
3004 saveenv - save environment variables to persistent storage
3005 protect - enable or disable FLASH write protection
3006 erase - erase FLASH memory
3007 flinfo - print FLASH memory information
3008 bdinfo - print Board Info structure
3009 iminfo - print header information for application image
3010 coninfo - print console devices and informations
3011 ide - IDE sub-system
3012 loop - infinite loop on address range
3013 loopw - infinite write loop on address range
3014 mtest - simple RAM test
3015 icache - enable or disable instruction cache
3016 dcache - enable or disable data cache
3017 reset - Perform RESET of the CPU
3018 echo - echo args to console
3019 version - print monitor version
3020 help - print online help
3021 ? - alias for 'help'
3024 Monitor Commands - Detailed Description:
3025 ========================================
3029 For now: just type "help <command>".
3032 Environment Variables:
3033 ======================
3035 U-Boot supports user configuration using Environment Variables which
3036 can be made persistent by saving to Flash memory.
3038 Environment Variables are set using "setenv", printed using
3039 "printenv", and saved to Flash using "saveenv". Using "setenv"
3040 without a value can be used to delete a variable from the
3041 environment. As long as you don't save the environment you are
3042 working with an in-memory copy. In case the Flash area containing the
3043 environment is erased by accident, a default environment is provided.
3045 Some configuration options can be set using Environment Variables.
3047 List of environment variables (most likely not complete):
3049 baudrate - see CONFIG_BAUDRATE
3051 bootdelay - see CONFIG_BOOTDELAY
3053 bootcmd - see CONFIG_BOOTCOMMAND
3055 bootargs - Boot arguments when booting an RTOS image
3057 bootfile - Name of the image to load with TFTP
3059 bootm_low - Memory range available for image processing in the bootm
3060 command can be restricted. This variable is given as
3061 a hexadecimal number and defines lowest address allowed
3062 for use by the bootm command. See also "bootm_size"
3063 environment variable. Address defined by "bootm_low" is
3064 also the base of the initial memory mapping for the Linux
3065 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ.
3067 bootm_size - Memory range available for image processing in the bootm
3068 command can be restricted. This variable is given as
3069 a hexadecimal number and defines the size of the region
3070 allowed for use by the bootm command. See also "bootm_low"
3071 environment variable.
3073 updatefile - Location of the software update file on a TFTP server, used
3074 by the automatic software update feature. Please refer to
3075 documentation in doc/README.update for more details.
3077 autoload - if set to "no" (any string beginning with 'n'),
3078 "bootp" will just load perform a lookup of the
3079 configuration from the BOOTP server, but not try to
3080 load any image using TFTP
3082 autostart - if set to "yes", an image loaded using the "bootp",
3083 "rarpboot", "tftpboot" or "diskboot" commands will
3084 be automatically started (by internally calling
3087 If set to "no", a standalone image passed to the
3088 "bootm" command will be copied to the load address
3089 (and eventually uncompressed), but NOT be started.
3090 This can be used to load and uncompress arbitrary
3093 i2cfast - (PPC405GP|PPC405EP only)
3094 if set to 'y' configures Linux I2C driver for fast
3095 mode (400kHZ). This environment variable is used in
3096 initialization code. So, for changes to be effective
3097 it must be saved and board must be reset.
3099 initrd_high - restrict positioning of initrd images:
3100 If this variable is not set, initrd images will be
3101 copied to the highest possible address in RAM; this
3102 is usually what you want since it allows for
3103 maximum initrd size. If for some reason you want to
3104 make sure that the initrd image is loaded below the
3105 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3106 variable to a value of "no" or "off" or "0".
3107 Alternatively, you can set it to a maximum upper
3108 address to use (U-Boot will still check that it
3109 does not overwrite the U-Boot stack and data).
3111 For instance, when you have a system with 16 MB
3112 RAM, and want to reserve 4 MB from use by Linux,
3113 you can do this by adding "mem=12M" to the value of
3114 the "bootargs" variable. However, now you must make
3115 sure that the initrd image is placed in the first
3116 12 MB as well - this can be done with
3118 setenv initrd_high 00c00000
3120 If you set initrd_high to 0xFFFFFFFF, this is an
3121 indication to U-Boot that all addresses are legal
3122 for the Linux kernel, including addresses in flash
3123 memory. In this case U-Boot will NOT COPY the
3124 ramdisk at all. This may be useful to reduce the
3125 boot time on your system, but requires that this
3126 feature is supported by your Linux kernel.
3128 ipaddr - IP address; needed for tftpboot command
3130 loadaddr - Default load address for commands like "bootp",
3131 "rarpboot", "tftpboot", "loadb" or "diskboot"
3133 loads_echo - see CONFIG_LOADS_ECHO
3135 serverip - TFTP server IP address; needed for tftpboot command
3137 bootretry - see CONFIG_BOOT_RETRY_TIME
3139 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3141 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3143 ethprime - When CONFIG_NET_MULTI is enabled controls which
3144 interface is used first.
3146 ethact - When CONFIG_NET_MULTI is enabled controls which
3147 interface is currently active. For example you
3148 can do the following
3150 => setenv ethact FEC
3151 => ping 192.168.0.1 # traffic sent on FEC
3152 => setenv ethact SCC
3153 => ping 10.0.0.1 # traffic sent on SCC
3155 ethrotate - When set to "no" U-Boot does not go through all
3156 available network interfaces.
3157 It just stays at the currently selected interface.
3159 netretry - When set to "no" each network operation will
3160 either succeed or fail without retrying.
3161 When set to "once" the network operation will
3162 fail when all the available network interfaces
3163 are tried once without success.
3164 Useful on scripts which control the retry operation
3167 npe_ucode - set load address for the NPE microcode
3169 tftpsrcport - If this is set, the value is used for TFTP's
3172 tftpdstport - If this is set, the value is used for TFTP's UDP
3173 destination port instead of the Well Know Port 69.
3175 tftpblocksize - Block size to use for TFTP transfers; if not set,
3176 we use the TFTP server's default block size
3178 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3179 seconds, minimum value is 1000 = 1 second). Defines
3180 when a packet is considered to be lost so it has to
3181 be retransmitted. The default is 5000 = 5 seconds.
3182 Lowering this value may make downloads succeed
3183 faster in networks with high packet loss rates or
3184 with unreliable TFTP servers.
3186 vlan - When set to a value < 4095 the traffic over
3187 Ethernet is encapsulated/received over 802.1q
3190 The following environment variables may be used and automatically
3191 updated by the network boot commands ("bootp" and "rarpboot"),
3192 depending the information provided by your boot server:
3194 bootfile - see above
3195 dnsip - IP address of your Domain Name Server
3196 dnsip2 - IP address of your secondary Domain Name Server
3197 gatewayip - IP address of the Gateway (Router) to use
3198 hostname - Target hostname
3200 netmask - Subnet Mask
3201 rootpath - Pathname of the root filesystem on the NFS server
3202 serverip - see above
3205 There are two special Environment Variables:
3207 serial# - contains hardware identification information such
3208 as type string and/or serial number
3209 ethaddr - Ethernet address
3211 These variables can be set only once (usually during manufacturing of
3212 the board). U-Boot refuses to delete or overwrite these variables
3213 once they have been set once.
3216 Further special Environment Variables:
3218 ver - Contains the U-Boot version string as printed
3219 with the "version" command. This variable is
3220 readonly (see CONFIG_VERSION_VARIABLE).
3223 Please note that changes to some configuration parameters may take
3224 only effect after the next boot (yes, that's just like Windoze :-).
3227 Command Line Parsing:
3228 =====================
3230 There are two different command line parsers available with U-Boot:
3231 the old "simple" one, and the much more powerful "hush" shell:
3233 Old, simple command line parser:
3234 --------------------------------
3236 - supports environment variables (through setenv / saveenv commands)
3237 - several commands on one line, separated by ';'
3238 - variable substitution using "... ${name} ..." syntax
3239 - special characters ('$', ';') can be escaped by prefixing with '\',
3241 setenv bootcmd bootm \${address}
3242 - You can also escape text by enclosing in single apostrophes, for example:
3243 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3248 - similar to Bourne shell, with control structures like
3249 if...then...else...fi, for...do...done; while...do...done,
3250 until...do...done, ...
3251 - supports environment ("global") variables (through setenv / saveenv
3252 commands) and local shell variables (through standard shell syntax
3253 "name=value"); only environment variables can be used with "run"
3259 (1) If a command line (or an environment variable executed by a "run"
3260 command) contains several commands separated by semicolon, and
3261 one of these commands fails, then the remaining commands will be
3264 (2) If you execute several variables with one call to run (i. e.
3265 calling run with a list of variables as arguments), any failing
3266 command will cause "run" to terminate, i. e. the remaining
3267 variables are not executed.
3269 Note for Redundant Ethernet Interfaces:
3270 =======================================
3272 Some boards come with redundant Ethernet interfaces; U-Boot supports
3273 such configurations and is capable of automatic selection of a
3274 "working" interface when needed. MAC assignment works as follows:
3276 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3277 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3278 "eth1addr" (=>eth1), "eth2addr", ...
3280 If the network interface stores some valid MAC address (for instance
3281 in SROM), this is used as default address if there is NO correspon-
3282 ding setting in the environment; if the corresponding environment
3283 variable is set, this overrides the settings in the card; that means:
3285 o If the SROM has a valid MAC address, and there is no address in the
3286 environment, the SROM's address is used.
3288 o If there is no valid address in the SROM, and a definition in the
3289 environment exists, then the value from the environment variable is
3292 o If both the SROM and the environment contain a MAC address, and
3293 both addresses are the same, this MAC address is used.
3295 o If both the SROM and the environment contain a MAC address, and the
3296 addresses differ, the value from the environment is used and a
3299 o If neither SROM nor the environment contain a MAC address, an error
3302 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3303 will be programmed into hardware as part of the initialization process. This
3304 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3305 The naming convention is as follows:
3306 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3311 U-Boot is capable of booting (and performing other auxiliary operations on)
3312 images in two formats:
3314 New uImage format (FIT)
3315 -----------------------
3317 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3318 to Flattened Device Tree). It allows the use of images with multiple
3319 components (several kernels, ramdisks, etc.), with contents protected by
3320 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3326 Old image format is based on binary files which can be basically anything,
3327 preceded by a special header; see the definitions in include/image.h for
3328 details; basically, the header defines the following image properties:
3330 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3331 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3332 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3333 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3335 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3336 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3337 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3338 * Compression Type (uncompressed, gzip, bzip2)
3344 The header is marked by a special Magic Number, and both the header
3345 and the data portions of the image are secured against corruption by
3352 Although U-Boot should support any OS or standalone application
3353 easily, the main focus has always been on Linux during the design of
3356 U-Boot includes many features that so far have been part of some
3357 special "boot loader" code within the Linux kernel. Also, any
3358 "initrd" images to be used are no longer part of one big Linux image;
3359 instead, kernel and "initrd" are separate images. This implementation
3360 serves several purposes:
3362 - the same features can be used for other OS or standalone
3363 applications (for instance: using compressed images to reduce the
3364 Flash memory footprint)
3366 - it becomes much easier to port new Linux kernel versions because
3367 lots of low-level, hardware dependent stuff are done by U-Boot
3369 - the same Linux kernel image can now be used with different "initrd"
3370 images; of course this also means that different kernel images can
3371 be run with the same "initrd". This makes testing easier (you don't
3372 have to build a new "zImage.initrd" Linux image when you just
3373 change a file in your "initrd"). Also, a field-upgrade of the
3374 software is easier now.
3380 Porting Linux to U-Boot based systems:
3381 ---------------------------------------
3383 U-Boot cannot save you from doing all the necessary modifications to
3384 configure the Linux device drivers for use with your target hardware
3385 (no, we don't intend to provide a full virtual machine interface to
3388 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3390 Just make sure your machine specific header file (for instance
3391 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3392 Information structure as we define in include/asm-<arch>/u-boot.h,
3393 and make sure that your definition of IMAP_ADDR uses the same value
3394 as your U-Boot configuration in CONFIG_SYS_IMMR.
3397 Configuring the Linux kernel:
3398 -----------------------------
3400 No specific requirements for U-Boot. Make sure you have some root
3401 device (initial ramdisk, NFS) for your target system.
3404 Building a Linux Image:
3405 -----------------------
3407 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3408 not used. If you use recent kernel source, a new build target
3409 "uImage" will exist which automatically builds an image usable by
3410 U-Boot. Most older kernels also have support for a "pImage" target,
3411 which was introduced for our predecessor project PPCBoot and uses a
3412 100% compatible format.
3421 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3422 encapsulate a compressed Linux kernel image with header information,
3423 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3425 * build a standard "vmlinux" kernel image (in ELF binary format):
3427 * convert the kernel into a raw binary image:
3429 ${CROSS_COMPILE}-objcopy -O binary \
3430 -R .note -R .comment \
3431 -S vmlinux linux.bin
3433 * compress the binary image:
3437 * package compressed binary image for U-Boot:
3439 mkimage -A ppc -O linux -T kernel -C gzip \
3440 -a 0 -e 0 -n "Linux Kernel Image" \
3441 -d linux.bin.gz uImage
3444 The "mkimage" tool can also be used to create ramdisk images for use
3445 with U-Boot, either separated from the Linux kernel image, or
3446 combined into one file. "mkimage" encapsulates the images with a 64
3447 byte header containing information about target architecture,
3448 operating system, image type, compression method, entry points, time
3449 stamp, CRC32 checksums, etc.
3451 "mkimage" can be called in two ways: to verify existing images and
3452 print the header information, or to build new images.
3454 In the first form (with "-l" option) mkimage lists the information
3455 contained in the header of an existing U-Boot image; this includes
3456 checksum verification:
3458 tools/mkimage -l image
3459 -l ==> list image header information
3461 The second form (with "-d" option) is used to build a U-Boot image
3462 from a "data file" which is used as image payload:
3464 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3465 -n name -d data_file image
3466 -A ==> set architecture to 'arch'
3467 -O ==> set operating system to 'os'
3468 -T ==> set image type to 'type'
3469 -C ==> set compression type 'comp'
3470 -a ==> set load address to 'addr' (hex)
3471 -e ==> set entry point to 'ep' (hex)
3472 -n ==> set image name to 'name'
3473 -d ==> use image data from 'datafile'
3475 Right now, all Linux kernels for PowerPC systems use the same load
3476 address (0x00000000), but the entry point address depends on the
3479 - 2.2.x kernels have the entry point at 0x0000000C,
3480 - 2.3.x and later kernels have the entry point at 0x00000000.
3482 So a typical call to build a U-Boot image would read:
3484 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3485 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3486 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3487 > examples/uImage.TQM850L
3488 Image Name: 2.4.4 kernel for TQM850L
3489 Created: Wed Jul 19 02:34:59 2000
3490 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3491 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3492 Load Address: 0x00000000
3493 Entry Point: 0x00000000
3495 To verify the contents of the image (or check for corruption):
3497 -> tools/mkimage -l examples/uImage.TQM850L
3498 Image Name: 2.4.4 kernel for TQM850L
3499 Created: Wed Jul 19 02:34:59 2000
3500 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3501 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3502 Load Address: 0x00000000
3503 Entry Point: 0x00000000
3505 NOTE: for embedded systems where boot time is critical you can trade
3506 speed for memory and install an UNCOMPRESSED image instead: this
3507 needs more space in Flash, but boots much faster since it does not
3508 need to be uncompressed:
3510 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3511 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3512 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3513 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3514 > examples/uImage.TQM850L-uncompressed
3515 Image Name: 2.4.4 kernel for TQM850L
3516 Created: Wed Jul 19 02:34:59 2000
3517 Image Type: PowerPC Linux Kernel Image (uncompressed)
3518 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3519 Load Address: 0x00000000
3520 Entry Point: 0x00000000
3523 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3524 when your kernel is intended to use an initial ramdisk:
3526 -> tools/mkimage -n 'Simple Ramdisk Image' \
3527 > -A ppc -O linux -T ramdisk -C gzip \
3528 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3529 Image Name: Simple Ramdisk Image
3530 Created: Wed Jan 12 14:01:50 2000
3531 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3532 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3533 Load Address: 0x00000000
3534 Entry Point: 0x00000000
3537 Installing a Linux Image:
3538 -------------------------
3540 To downloading a U-Boot image over the serial (console) interface,
3541 you must convert the image to S-Record format:
3543 objcopy -I binary -O srec examples/image examples/image.srec
3545 The 'objcopy' does not understand the information in the U-Boot
3546 image header, so the resulting S-Record file will be relative to
3547 address 0x00000000. To load it to a given address, you need to
3548 specify the target address as 'offset' parameter with the 'loads'
3551 Example: install the image to address 0x40100000 (which on the
3552 TQM8xxL is in the first Flash bank):
3554 => erase 40100000 401FFFFF
3560 ## Ready for S-Record download ...
3561 ~>examples/image.srec
3562 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3564 15989 15990 15991 15992
3565 [file transfer complete]
3567 ## Start Addr = 0x00000000
3570 You can check the success of the download using the 'iminfo' command;
3571 this includes a checksum verification so you can be sure no data
3572 corruption happened:
3576 ## Checking Image at 40100000 ...
3577 Image Name: 2.2.13 for initrd on TQM850L
3578 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3579 Data Size: 335725 Bytes = 327 kB = 0 MB
3580 Load Address: 00000000
3581 Entry Point: 0000000c
3582 Verifying Checksum ... OK
3588 The "bootm" command is used to boot an application that is stored in
3589 memory (RAM or Flash). In case of a Linux kernel image, the contents
3590 of the "bootargs" environment variable is passed to the kernel as
3591 parameters. You can check and modify this variable using the
3592 "printenv" and "setenv" commands:
3595 => printenv bootargs
3596 bootargs=root=/dev/ram
3598 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3600 => printenv bootargs
3601 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3604 ## Booting Linux kernel at 40020000 ...
3605 Image Name: 2.2.13 for NFS on TQM850L
3606 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3607 Data Size: 381681 Bytes = 372 kB = 0 MB
3608 Load Address: 00000000
3609 Entry Point: 0000000c
3610 Verifying Checksum ... OK
3611 Uncompressing Kernel Image ... OK
3612 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
3613 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3614 time_init: decrementer frequency = 187500000/60
3615 Calibrating delay loop... 49.77 BogoMIPS
3616 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3619 If you want to boot a Linux kernel with initial RAM disk, you pass
3620 the memory addresses of both the kernel and the initrd image (PPBCOOT
3621 format!) to the "bootm" command:
3623 => imi 40100000 40200000
3625 ## Checking Image at 40100000 ...
3626 Image Name: 2.2.13 for initrd on TQM850L
3627 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3628 Data Size: 335725 Bytes = 327 kB = 0 MB
3629 Load Address: 00000000
3630 Entry Point: 0000000c
3631 Verifying Checksum ... OK
3633 ## Checking Image at 40200000 ...
3634 Image Name: Simple Ramdisk Image
3635 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3636 Data Size: 566530 Bytes = 553 kB = 0 MB
3637 Load Address: 00000000
3638 Entry Point: 00000000
3639 Verifying Checksum ... OK
3641 => bootm 40100000 40200000
3642 ## Booting Linux kernel at 40100000 ...
3643 Image Name: 2.2.13 for initrd on TQM850L
3644 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3645 Data Size: 335725 Bytes = 327 kB = 0 MB
3646 Load Address: 00000000
3647 Entry Point: 0000000c
3648 Verifying Checksum ... OK
3649 Uncompressing Kernel Image ... OK
3650 ## Loading RAMDisk Image at 40200000 ...
3651 Image Name: Simple Ramdisk Image
3652 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3653 Data Size: 566530 Bytes = 553 kB = 0 MB
3654 Load Address: 00000000
3655 Entry Point: 00000000
3656 Verifying Checksum ... OK
3657 Loading Ramdisk ... OK
3658 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
3659 Boot arguments: root=/dev/ram
3660 time_init: decrementer frequency = 187500000/60
3661 Calibrating delay loop... 49.77 BogoMIPS
3663 RAMDISK: Compressed image found at block 0
3664 VFS: Mounted root (ext2 filesystem).
3668 Boot Linux and pass a flat device tree:
3671 First, U-Boot must be compiled with the appropriate defines. See the section
3672 titled "Linux Kernel Interface" above for a more in depth explanation. The
3673 following is an example of how to start a kernel and pass an updated
3679 oft=oftrees/mpc8540ads.dtb
3680 => tftp $oftaddr $oft
3681 Speed: 1000, full duplex
3683 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3684 Filename 'oftrees/mpc8540ads.dtb'.
3685 Load address: 0x300000
3688 Bytes transferred = 4106 (100a hex)
3689 => tftp $loadaddr $bootfile
3690 Speed: 1000, full duplex
3692 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3694 Load address: 0x200000
3695 Loading:############
3697 Bytes transferred = 1029407 (fb51f hex)
3702 => bootm $loadaddr - $oftaddr
3703 ## Booting image at 00200000 ...
3704 Image Name: Linux-2.6.17-dirty
3705 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3706 Data Size: 1029343 Bytes = 1005.2 kB
3707 Load Address: 00000000
3708 Entry Point: 00000000
3709 Verifying Checksum ... OK
3710 Uncompressing Kernel Image ... OK
3711 Booting using flat device tree at 0x300000
3712 Using MPC85xx ADS machine description
3713 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3717 More About U-Boot Image Types:
3718 ------------------------------
3720 U-Boot supports the following image types:
3722 "Standalone Programs" are directly runnable in the environment
3723 provided by U-Boot; it is expected that (if they behave
3724 well) you can continue to work in U-Boot after return from
3725 the Standalone Program.
3726 "OS Kernel Images" are usually images of some Embedded OS which
3727 will take over control completely. Usually these programs
3728 will install their own set of exception handlers, device
3729 drivers, set up the MMU, etc. - this means, that you cannot
3730 expect to re-enter U-Boot except by resetting the CPU.
3731 "RAMDisk Images" are more or less just data blocks, and their
3732 parameters (address, size) are passed to an OS kernel that is
3734 "Multi-File Images" contain several images, typically an OS
3735 (Linux) kernel image and one or more data images like
3736 RAMDisks. This construct is useful for instance when you want
3737 to boot over the network using BOOTP etc., where the boot
3738 server provides just a single image file, but you want to get
3739 for instance an OS kernel and a RAMDisk image.
3741 "Multi-File Images" start with a list of image sizes, each
3742 image size (in bytes) specified by an "uint32_t" in network
3743 byte order. This list is terminated by an "(uint32_t)0".
3744 Immediately after the terminating 0 follow the images, one by
3745 one, all aligned on "uint32_t" boundaries (size rounded up to
3746 a multiple of 4 bytes).
3748 "Firmware Images" are binary images containing firmware (like
3749 U-Boot or FPGA images) which usually will be programmed to
3752 "Script files" are command sequences that will be executed by
3753 U-Boot's command interpreter; this feature is especially
3754 useful when you configure U-Boot to use a real shell (hush)
3755 as command interpreter.
3761 One of the features of U-Boot is that you can dynamically load and
3762 run "standalone" applications, which can use some resources of
3763 U-Boot like console I/O functions or interrupt services.
3765 Two simple examples are included with the sources:
3770 'examples/hello_world.c' contains a small "Hello World" Demo
3771 application; it is automatically compiled when you build U-Boot.
3772 It's configured to run at address 0x00040004, so you can play with it
3776 ## Ready for S-Record download ...
3777 ~>examples/hello_world.srec
3778 1 2 3 4 5 6 7 8 9 10 11 ...
3779 [file transfer complete]
3781 ## Start Addr = 0x00040004
3783 => go 40004 Hello World! This is a test.
3784 ## Starting application at 0x00040004 ...
3795 Hit any key to exit ...
3797 ## Application terminated, rc = 0x0
3799 Another example, which demonstrates how to register a CPM interrupt
3800 handler with the U-Boot code, can be found in 'examples/timer.c'.
3801 Here, a CPM timer is set up to generate an interrupt every second.
3802 The interrupt service routine is trivial, just printing a '.'
3803 character, but this is just a demo program. The application can be
3804 controlled by the following keys:
3806 ? - print current values og the CPM Timer registers
3807 b - enable interrupts and start timer
3808 e - stop timer and disable interrupts
3809 q - quit application
3812 ## Ready for S-Record download ...
3813 ~>examples/timer.srec
3814 1 2 3 4 5 6 7 8 9 10 11 ...
3815 [file transfer complete]
3817 ## Start Addr = 0x00040004
3820 ## Starting application at 0x00040004 ...
3823 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3826 [q, b, e, ?] Set interval 1000000 us
3829 [q, b, e, ?] ........
3830 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3833 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3836 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3839 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3841 [q, b, e, ?] ...Stopping timer
3843 [q, b, e, ?] ## Application terminated, rc = 0x0
3849 Over time, many people have reported problems when trying to use the
3850 "minicom" terminal emulation program for serial download. I (wd)
3851 consider minicom to be broken, and recommend not to use it. Under
3852 Unix, I recommend to use C-Kermit for general purpose use (and
3853 especially for kermit binary protocol download ("loadb" command), and
3854 use "cu" for S-Record download ("loads" command).
3856 Nevertheless, if you absolutely want to use it try adding this
3857 configuration to your "File transfer protocols" section:
3859 Name Program Name U/D FullScr IO-Red. Multi
3860 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3861 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3867 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3868 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3870 Building requires a cross environment; it is known to work on
3871 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3872 need gmake since the Makefiles are not compatible with BSD make).
3873 Note that the cross-powerpc package does not install include files;
3874 attempting to build U-Boot will fail because <machine/ansi.h> is
3875 missing. This file has to be installed and patched manually:
3877 # cd /usr/pkg/cross/powerpc-netbsd/include
3879 # ln -s powerpc machine
3880 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3881 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3883 Native builds *don't* work due to incompatibilities between native
3884 and U-Boot include files.
3886 Booting assumes that (the first part of) the image booted is a
3887 stage-2 loader which in turn loads and then invokes the kernel
3888 proper. Loader sources will eventually appear in the NetBSD source
3889 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3890 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3893 Implementation Internals:
3894 =========================
3896 The following is not intended to be a complete description of every
3897 implementation detail. However, it should help to understand the
3898 inner workings of U-Boot and make it easier to port it to custom
3902 Initial Stack, Global Data:
3903 ---------------------------
3905 The implementation of U-Boot is complicated by the fact that U-Boot
3906 starts running out of ROM (flash memory), usually without access to
3907 system RAM (because the memory controller is not initialized yet).
3908 This means that we don't have writable Data or BSS segments, and BSS
3909 is not initialized as zero. To be able to get a C environment working
3910 at all, we have to allocate at least a minimal stack. Implementation
3911 options for this are defined and restricted by the CPU used: Some CPU
3912 models provide on-chip memory (like the IMMR area on MPC8xx and
3913 MPC826x processors), on others (parts of) the data cache can be
3914 locked as (mis-) used as memory, etc.
3916 Chris Hallinan posted a good summary of these issues to the
3917 U-Boot mailing list:
3919 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3920 From: "Chris Hallinan" <clh@net1plus.com>
3921 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3924 Correct me if I'm wrong, folks, but the way I understand it
3925 is this: Using DCACHE as initial RAM for Stack, etc, does not
3926 require any physical RAM backing up the cache. The cleverness
3927 is that the cache is being used as a temporary supply of
3928 necessary storage before the SDRAM controller is setup. It's
3929 beyond the scope of this list to explain the details, but you
3930 can see how this works by studying the cache architecture and
3931 operation in the architecture and processor-specific manuals.
3933 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3934 is another option for the system designer to use as an
3935 initial stack/RAM area prior to SDRAM being available. Either
3936 option should work for you. Using CS 4 should be fine if your
3937 board designers haven't used it for something that would
3938 cause you grief during the initial boot! It is frequently not
3941 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
3942 with your processor/board/system design. The default value
3943 you will find in any recent u-boot distribution in
3944 walnut.h should work for you. I'd set it to a value larger
3945 than your SDRAM module. If you have a 64MB SDRAM module, set
3946 it above 400_0000. Just make sure your board has no resources
3947 that are supposed to respond to that address! That code in
3948 start.S has been around a while and should work as is when
3949 you get the config right.
3954 It is essential to remember this, since it has some impact on the C
3955 code for the initialization procedures:
3957 * Initialized global data (data segment) is read-only. Do not attempt
3960 * Do not use any uninitialized global data (or implicitely initialized
3961 as zero data - BSS segment) at all - this is undefined, initiali-
3962 zation is performed later (when relocating to RAM).
3964 * Stack space is very limited. Avoid big data buffers or things like
3967 Having only the stack as writable memory limits means we cannot use
3968 normal global data to share information beween the code. But it
3969 turned out that the implementation of U-Boot can be greatly
3970 simplified by making a global data structure (gd_t) available to all
3971 functions. We could pass a pointer to this data as argument to _all_
3972 functions, but this would bloat the code. Instead we use a feature of
3973 the GCC compiler (Global Register Variables) to share the data: we
3974 place a pointer (gd) to the global data into a register which we
3975 reserve for this purpose.
3977 When choosing a register for such a purpose we are restricted by the
3978 relevant (E)ABI specifications for the current architecture, and by
3979 GCC's implementation.
3981 For PowerPC, the following registers have specific use:
3983 R2: reserved for system use
3984 R3-R4: parameter passing and return values
3985 R5-R10: parameter passing
3986 R13: small data area pointer
3990 (U-Boot also uses R12 as internal GOT pointer. r12
3991 is a volatile register so r12 needs to be reset when
3992 going back and forth between asm and C)
3994 ==> U-Boot will use R2 to hold a pointer to the global data
3996 Note: on PPC, we could use a static initializer (since the
3997 address of the global data structure is known at compile time),
3998 but it turned out that reserving a register results in somewhat
3999 smaller code - although the code savings are not that big (on
4000 average for all boards 752 bytes for the whole U-Boot image,
4001 624 text + 127 data).
4003 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4004 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4006 ==> U-Boot will use P3 to hold a pointer to the global data
4008 On ARM, the following registers are used:
4010 R0: function argument word/integer result
4011 R1-R3: function argument word
4013 R10: stack limit (used only if stack checking if enabled)
4014 R11: argument (frame) pointer
4015 R12: temporary workspace
4018 R15: program counter
4020 ==> U-Boot will use R8 to hold a pointer to the global data
4022 On Nios II, the ABI is documented here:
4023 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4025 ==> U-Boot will use gp to hold a pointer to the global data
4027 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4028 to access small data sections, so gp is free.
4030 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4031 or current versions of GCC may "optimize" the code too much.
4036 U-Boot runs in system state and uses physical addresses, i.e. the
4037 MMU is not used either for address mapping nor for memory protection.
4039 The available memory is mapped to fixed addresses using the memory
4040 controller. In this process, a contiguous block is formed for each
4041 memory type (Flash, SDRAM, SRAM), even when it consists of several
4042 physical memory banks.
4044 U-Boot is installed in the first 128 kB of the first Flash bank (on
4045 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4046 booting and sizing and initializing DRAM, the code relocates itself
4047 to the upper end of DRAM. Immediately below the U-Boot code some
4048 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4049 configuration setting]. Below that, a structure with global Board
4050 Info data is placed, followed by the stack (growing downward).
4052 Additionally, some exception handler code is copied to the low 8 kB
4053 of DRAM (0x00000000 ... 0x00001FFF).
4055 So a typical memory configuration with 16 MB of DRAM could look like
4058 0x0000 0000 Exception Vector code
4061 0x0000 2000 Free for Application Use
4067 0x00FB FF20 Monitor Stack (Growing downward)
4068 0x00FB FFAC Board Info Data and permanent copy of global data
4069 0x00FC 0000 Malloc Arena
4072 0x00FE 0000 RAM Copy of Monitor Code
4073 ... eventually: LCD or video framebuffer
4074 ... eventually: pRAM (Protected RAM - unchanged by reset)
4075 0x00FF FFFF [End of RAM]
4078 System Initialization:
4079 ----------------------
4081 In the reset configuration, U-Boot starts at the reset entry point
4082 (on most PowerPC systems at address 0x00000100). Because of the reset
4083 configuration for CS0# this is a mirror of the onboard Flash memory.
4084 To be able to re-map memory U-Boot then jumps to its link address.
4085 To be able to implement the initialization code in C, a (small!)
4086 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4087 which provide such a feature like MPC8xx or MPC8260), or in a locked
4088 part of the data cache. After that, U-Boot initializes the CPU core,
4089 the caches and the SIU.
4091 Next, all (potentially) available memory banks are mapped using a
4092 preliminary mapping. For example, we put them on 512 MB boundaries
4093 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4094 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4095 programmed for SDRAM access. Using the temporary configuration, a
4096 simple memory test is run that determines the size of the SDRAM
4099 When there is more than one SDRAM bank, and the banks are of
4100 different size, the largest is mapped first. For equal size, the first
4101 bank (CS2#) is mapped first. The first mapping is always for address
4102 0x00000000, with any additional banks following immediately to create
4103 contiguous memory starting from 0.
4105 Then, the monitor installs itself at the upper end of the SDRAM area
4106 and allocates memory for use by malloc() and for the global Board
4107 Info data; also, the exception vector code is copied to the low RAM
4108 pages, and the final stack is set up.
4110 Only after this relocation will you have a "normal" C environment;
4111 until that you are restricted in several ways, mostly because you are
4112 running from ROM, and because the code will have to be relocated to a
4116 U-Boot Porting Guide:
4117 ----------------------
4119 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4123 int main(int argc, char *argv[])
4125 sighandler_t no_more_time;
4127 signal(SIGALRM, no_more_time);
4128 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4130 if (available_money > available_manpower) {
4131 Pay consultant to port U-Boot;
4135 Download latest U-Boot source;
4137 Subscribe to u-boot mailing list;
4140 email("Hi, I am new to U-Boot, how do I get started?");
4143 Read the README file in the top level directory;
4144 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4145 Read applicable doc/*.README;
4146 Read the source, Luke;
4147 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4150 if (available_money > toLocalCurrency ($2500))
4153 Add a lot of aggravation and time;
4155 if (a similar board exists) { /* hopefully... */
4156 cp -a board/<similar> board/<myboard>
4157 cp include/configs/<similar>.h include/configs/<myboard>.h
4159 Create your own board support subdirectory;
4160 Create your own board include/configs/<myboard>.h file;
4162 Edit new board/<myboard> files
4163 Edit new include/configs/<myboard>.h
4168 Add / modify source code;
4172 email("Hi, I am having problems...");
4174 Send patch file to the U-Boot email list;
4175 if (reasonable critiques)
4176 Incorporate improvements from email list code review;
4178 Defend code as written;
4184 void no_more_time (int sig)
4193 All contributions to U-Boot should conform to the Linux kernel
4194 coding style; see the file "Documentation/CodingStyle" and the script
4195 "scripts/Lindent" in your Linux kernel source directory. In sources
4196 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4197 spaces before parameters to function calls) is actually used.
4199 Source files originating from a different project (for example the
4200 MTD subsystem) are generally exempt from these guidelines and are not
4201 reformated to ease subsequent migration to newer versions of those
4204 Please note that U-Boot is implemented in C (and to some small parts in
4205 Assembler); no C++ is used, so please do not use C++ style comments (//)
4208 Please also stick to the following formatting rules:
4209 - remove any trailing white space
4210 - use TAB characters for indentation, not spaces
4211 - make sure NOT to use DOS '\r\n' line feeds
4212 - do not add more than 2 empty lines to source files
4213 - do not add trailing empty lines to source files
4215 Submissions which do not conform to the standards may be returned
4216 with a request to reformat the changes.
4222 Since the number of patches for U-Boot is growing, we need to
4223 establish some rules. Submissions which do not conform to these rules
4224 may be rejected, even when they contain important and valuable stuff.
4226 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4228 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4229 see http://lists.denx.de/mailman/listinfo/u-boot
4231 When you send a patch, please include the following information with
4234 * For bug fixes: a description of the bug and how your patch fixes
4235 this bug. Please try to include a way of demonstrating that the
4236 patch actually fixes something.
4238 * For new features: a description of the feature and your
4241 * A CHANGELOG entry as plaintext (separate from the patch)
4243 * For major contributions, your entry to the CREDITS file
4245 * When you add support for a new board, don't forget to add this
4246 board to the MAKEALL script, too.
4248 * If your patch adds new configuration options, don't forget to
4249 document these in the README file.
4251 * The patch itself. If you are using git (which is *strongly*
4252 recommended) you can easily generate the patch using the
4253 "git-format-patch". If you then use "git-send-email" to send it to
4254 the U-Boot mailing list, you will avoid most of the common problems
4255 with some other mail clients.
4257 If you cannot use git, use "diff -purN OLD NEW". If your version of
4258 diff does not support these options, then get the latest version of
4261 The current directory when running this command shall be the parent
4262 directory of the U-Boot source tree (i. e. please make sure that
4263 your patch includes sufficient directory information for the
4266 We prefer patches as plain text. MIME attachments are discouraged,
4267 and compressed attachments must not be used.
4269 * If one logical set of modifications affects or creates several
4270 files, all these changes shall be submitted in a SINGLE patch file.
4272 * Changesets that contain different, unrelated modifications shall be
4273 submitted as SEPARATE patches, one patch per changeset.
4278 * Before sending the patch, run the MAKEALL script on your patched
4279 source tree and make sure that no errors or warnings are reported
4280 for any of the boards.
4282 * Keep your modifications to the necessary minimum: A patch
4283 containing several unrelated changes or arbitrary reformats will be
4284 returned with a request to re-formatting / split it.
4286 * If you modify existing code, make sure that your new code does not
4287 add to the memory footprint of the code ;-) Small is beautiful!
4288 When adding new features, these should compile conditionally only
4289 (using #ifdef), and the resulting code with the new feature
4290 disabled must not need more memory than the old code without your
4293 * Remember that there is a size limit of 100 kB per message on the
4294 u-boot mailing list. Bigger patches will be moderated. If they are
4295 reasonable and not too big, they will be acknowledged. But patches
4296 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob