2 # (C) Copyright 2000 - 2008
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 - board Board dependent files
142 - common Misc architecture independent functions
143 - cpu CPU specific files
144 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
145 - arm720t Files specific to ARM 720 CPUs
146 - arm920t Files specific to ARM 920 CPUs
147 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
148 - imx Files specific to Freescale MC9328 i.MX CPUs
149 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
150 - arm925t Files specific to ARM 925 CPUs
151 - arm926ejs Files specific to ARM 926 CPUs
152 - arm1136 Files specific to ARM 1136 CPUs
153 - at32ap Files specific to Atmel AVR32 AP CPUs
154 - blackfin Files specific to Analog Devices Blackfin CPUs
155 - i386 Files specific to i386 CPUs
156 - ixp Files specific to Intel XScale IXP CPUs
157 - leon2 Files specific to Gaisler LEON2 SPARC CPU
158 - leon3 Files specific to Gaisler LEON3 SPARC CPU
159 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
160 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
161 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
162 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
163 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
164 - mips Files specific to MIPS CPUs
165 - mpc5xx Files specific to Freescale MPC5xx CPUs
166 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
167 - mpc8xx Files specific to Freescale MPC8xx CPUs
168 - mpc8220 Files specific to Freescale MPC8220 CPUs
169 - mpc824x Files specific to Freescale MPC824x CPUs
170 - mpc8260 Files specific to Freescale MPC8260 CPUs
171 - mpc85xx Files specific to Freescale MPC85xx CPUs
172 - nios Files specific to Altera NIOS CPUs
173 - nios2 Files specific to Altera Nios-II CPUs
174 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
175 - pxa Files specific to Intel XScale PXA CPUs
176 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
177 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
178 - disk Code for disk drive partition handling
179 - doc Documentation (don't expect too much)
180 - drivers Commonly used device drivers
181 - dtt Digital Thermometer and Thermostat drivers
182 - examples Example code for standalone applications, etc.
183 - include Header Files
184 - lib_arm Files generic to ARM architecture
185 - lib_avr32 Files generic to AVR32 architecture
186 - lib_blackfin Files generic to Blackfin architecture
187 - lib_generic Files generic to all architectures
188 - lib_i386 Files generic to i386 architecture
189 - lib_m68k Files generic to m68k architecture
190 - lib_mips Files generic to MIPS architecture
191 - lib_nios Files generic to NIOS architecture
192 - lib_ppc Files generic to PowerPC architecture
193 - lib_sparc Files generic to SPARC architecture
194 - libfdt Library files to support flattened device trees
195 - net Networking code
196 - post Power On Self Test
197 - rtc Real Time Clock drivers
198 - tools Tools to build S-Record or U-Boot images, etc.
200 Software Configuration:
201 =======================
203 Configuration is usually done using C preprocessor defines; the
204 rationale behind that is to avoid dead code whenever possible.
206 There are two classes of configuration variables:
208 * Configuration _OPTIONS_:
209 These are selectable by the user and have names beginning with
212 * Configuration _SETTINGS_:
213 These depend on the hardware etc. and should not be meddled with if
214 you don't know what you're doing; they have names beginning with
217 Later we will add a configuration tool - probably similar to or even
218 identical to what's used for the Linux kernel. Right now, we have to
219 do the configuration by hand, which means creating some symbolic
220 links and editing some configuration files. We use the TQM8xxL boards
224 Selection of Processor Architecture and Board Type:
225 ---------------------------------------------------
227 For all supported boards there are ready-to-use default
228 configurations available; just type "make <board_name>_config".
230 Example: For a TQM823L module type:
235 For the Cogent platform, you need to specify the CPU type as well;
236 e.g. "make cogent_mpc8xx_config". And also configure the cogent
237 directory according to the instructions in cogent/README.
240 Configuration Options:
241 ----------------------
243 Configuration depends on the combination of board and CPU type; all
244 such information is kept in a configuration file
245 "include/configs/<board_name>.h".
247 Example: For a TQM823L module, all configuration settings are in
248 "include/configs/TQM823L.h".
251 Many of the options are named exactly as the corresponding Linux
252 kernel configuration options. The intention is to make it easier to
253 build a config tool - later.
256 The following options need to be configured:
258 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
260 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
262 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
263 Define exactly one, e.g. CONFIG_ATSTK1002
265 - CPU Module Type: (if CONFIG_COGENT is defined)
266 Define exactly one of
268 --- FIXME --- not tested yet:
269 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
270 CONFIG_CMA287_23, CONFIG_CMA287_50
272 - Motherboard Type: (if CONFIG_COGENT is defined)
273 Define exactly one of
274 CONFIG_CMA101, CONFIG_CMA102
276 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
277 Define one or more of
280 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
281 Define one or more of
282 CONFIG_LCD_HEARTBEAT - update a character position on
283 the LCD display every second with
286 - Board flavour: (if CONFIG_MPC8260ADS is defined)
289 CONFIG_SYS_8260ADS - original MPC8260ADS
290 CONFIG_SYS_8266ADS - MPC8266ADS
291 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
292 CONFIG_SYS_8272ADS - MPC8272ADS
294 - MPC824X Family Member (if CONFIG_MPC824X is defined)
295 Define exactly one of
296 CONFIG_MPC8240, CONFIG_MPC8245
298 - 8xx CPU Options: (if using an MPC8xx CPU)
299 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
300 get_gclk_freq() cannot work
301 e.g. if there is no 32KHz
302 reference PIT/RTC clock
303 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
306 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
307 CONFIG_SYS_8xx_CPUCLK_MIN
308 CONFIG_SYS_8xx_CPUCLK_MAX
309 CONFIG_8xx_CPUCLK_DEFAULT
310 See doc/README.MPC866
312 CONFIG_SYS_MEASURE_CPUCLK
314 Define this to measure the actual CPU clock instead
315 of relying on the correctness of the configured
316 values. Mostly useful for board bringup to make sure
317 the PLL is locked at the intended frequency. Note
318 that this requires a (stable) reference clock (32 kHz
319 RTC clock or CONFIG_SYS_8XX_XIN)
321 CONFIG_SYS_DELAYED_ICACHE
323 Define this option if you want to enable the
324 ICache only when Code runs from RAM.
326 - Intel Monahans options:
327 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
329 Defines the Monahans run mode to oscillator
330 ratio. Valid values are 8, 16, 24, 31. The core
331 frequency is this value multiplied by 13 MHz.
333 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
335 Defines the Monahans turbo mode to oscillator
336 ratio. Valid values are 1 (default if undefined) and
337 2. The core frequency as calculated above is multiplied
340 - Linux Kernel Interface:
343 U-Boot stores all clock information in Hz
344 internally. For binary compatibility with older Linux
345 kernels (which expect the clocks passed in the
346 bd_info data to be in MHz) the environment variable
347 "clocks_in_mhz" can be defined so that U-Boot
348 converts clock data to MHZ before passing it to the
350 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
351 "clocks_in_mhz=1" is automatically included in the
354 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
356 When transferring memsize parameter to linux, some versions
357 expect it to be in bytes, others in MB.
358 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
362 New kernel versions are expecting firmware settings to be
363 passed using flattened device trees (based on open firmware
367 * New libfdt-based support
368 * Adds the "fdt" command
369 * The bootm command automatically updates the fdt
371 OF_CPU - The proper name of the cpus node (only required for
372 MPC512X and MPC5xxx based boards).
373 OF_SOC - The proper name of the soc node (only required for
374 MPC512X and MPC5xxx based boards).
375 OF_TBCLK - The timebase frequency.
376 OF_STDOUT_PATH - The path to the console device
378 boards with QUICC Engines require OF_QE to set UCC MAC
381 CONFIG_OF_BOARD_SETUP
383 Board code has addition modification that it wants to make
384 to the flat device tree before handing it off to the kernel
388 This define fills in the correct boot CPU in the boot
389 param header, the default value is zero if undefined.
391 - vxWorks boot parameters:
393 bootvx constructs a valid bootline using the following
394 environments variables: bootfile, ipaddr, serverip, hostname.
395 It loads the vxWorks image pointed bootfile.
397 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
398 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
399 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
400 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
402 CONFIG_SYS_VXWORKS_ADD_PARAMS
404 Add it at the end of the bootline. E.g "u=username pw=secret"
406 Note: If a "bootargs" environment is defined, it will overwride
407 the defaults discussed just above.
412 Define this if you want support for Amba PrimeCell PL010 UARTs.
416 Define this if you want support for Amba PrimeCell PL011 UARTs.
420 If you have Amba PrimeCell PL011 UARTs, set this variable to
421 the clock speed of the UARTs.
425 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
426 define this to a list of base addresses for each (supported)
427 port. See e.g. include/configs/versatile.h
431 Depending on board, define exactly one serial port
432 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
433 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
434 console by defining CONFIG_8xx_CONS_NONE
436 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
437 port routines must be defined elsewhere
438 (i.e. serial_init(), serial_getc(), ...)
441 Enables console device for a color framebuffer. Needs following
442 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
443 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
445 VIDEO_HW_RECTFILL graphic chip supports
448 VIDEO_HW_BITBLT graphic chip supports
449 bit-blit (cf. smiLynxEM)
450 VIDEO_VISIBLE_COLS visible pixel columns
452 VIDEO_VISIBLE_ROWS visible pixel rows
453 VIDEO_PIXEL_SIZE bytes per pixel
454 VIDEO_DATA_FORMAT graphic data format
455 (0-5, cf. cfb_console.c)
456 VIDEO_FB_ADRS framebuffer address
457 VIDEO_KBD_INIT_FCT keyboard int fct
458 (i.e. i8042_kbd_init())
459 VIDEO_TSTC_FCT test char fct
461 VIDEO_GETC_FCT get char fct
463 CONFIG_CONSOLE_CURSOR cursor drawing on/off
464 (requires blink timer
466 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
467 CONFIG_CONSOLE_TIME display time/date info in
469 (requires CONFIG_CMD_DATE)
470 CONFIG_VIDEO_LOGO display Linux logo in
472 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
473 linux_logo.h for logo.
474 Requires CONFIG_VIDEO_LOGO
475 CONFIG_CONSOLE_EXTRA_INFO
476 additional board info beside
479 When CONFIG_CFB_CONSOLE is defined, video console is
480 default i/o. Serial console can be forced with
481 environment 'console=serial'.
483 When CONFIG_SILENT_CONSOLE is defined, all console
484 messages (by U-Boot and Linux!) can be silenced with
485 the "silent" environment variable. See
486 doc/README.silent for more information.
489 CONFIG_BAUDRATE - in bps
490 Select one of the baudrates listed in
491 CONFIG_SYS_BAUDRATE_TABLE, see below.
492 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
494 - Console Rx buffer length
495 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
496 the maximum receive buffer length for the SMC.
497 This option is actual only for 82xx and 8xx possible.
498 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
499 must be defined, to setup the maximum idle timeout for
502 - Interrupt driven serial port input:
503 CONFIG_SERIAL_SOFTWARE_FIFO
506 Use an interrupt handler for receiving data on the
507 serial port. It also enables using hardware handshake
508 (RTS/CTS) and UART's built-in FIFO. Set the number of
509 bytes the interrupt driven input buffer should have.
511 Leave undefined to disable this feature, including
512 disable the buffer and hardware handshake.
514 - Console UART Number:
518 If defined internal UART1 (and not UART0) is used
519 as default U-Boot console.
521 - Boot Delay: CONFIG_BOOTDELAY - in seconds
522 Delay before automatically booting the default image;
523 set to -1 to disable autoboot.
525 See doc/README.autoboot for these options that
526 work with CONFIG_BOOTDELAY. None are required.
527 CONFIG_BOOT_RETRY_TIME
528 CONFIG_BOOT_RETRY_MIN
529 CONFIG_AUTOBOOT_KEYED
530 CONFIG_AUTOBOOT_PROMPT
531 CONFIG_AUTOBOOT_DELAY_STR
532 CONFIG_AUTOBOOT_STOP_STR
533 CONFIG_AUTOBOOT_DELAY_STR2
534 CONFIG_AUTOBOOT_STOP_STR2
535 CONFIG_ZERO_BOOTDELAY_CHECK
536 CONFIG_RESET_TO_RETRY
540 Only needed when CONFIG_BOOTDELAY is enabled;
541 define a command string that is automatically executed
542 when no character is read on the console interface
543 within "Boot Delay" after reset.
546 This can be used to pass arguments to the bootm
547 command. The value of CONFIG_BOOTARGS goes into the
548 environment value "bootargs".
550 CONFIG_RAMBOOT and CONFIG_NFSBOOT
551 The value of these goes into the environment as
552 "ramboot" and "nfsboot" respectively, and can be used
553 as a convenience, when switching between booting from
559 When this option is #defined, the existence of the
560 environment variable "preboot" will be checked
561 immediately before starting the CONFIG_BOOTDELAY
562 countdown and/or running the auto-boot command resp.
563 entering interactive mode.
565 This feature is especially useful when "preboot" is
566 automatically generated or modified. For an example
567 see the LWMON board specific code: here "preboot" is
568 modified when the user holds down a certain
569 combination of keys on the (special) keyboard when
572 - Serial Download Echo Mode:
574 If defined to 1, all characters received during a
575 serial download (using the "loads" command) are
576 echoed back. This might be needed by some terminal
577 emulations (like "cu"), but may as well just take
578 time on others. This setting #define's the initial
579 value of the "loads_echo" environment variable.
581 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
583 Select one of the baudrates listed in
584 CONFIG_SYS_BAUDRATE_TABLE, see below.
587 Monitor commands can be included or excluded
588 from the build by using the #include files
589 "config_cmd_all.h" and #undef'ing unwanted
590 commands, or using "config_cmd_default.h"
591 and augmenting with additional #define's
594 The default command configuration includes all commands
595 except those marked below with a "*".
597 CONFIG_CMD_ASKENV * ask for env variable
598 CONFIG_CMD_BDI bdinfo
599 CONFIG_CMD_BEDBUG * Include BedBug Debugger
600 CONFIG_CMD_BMP * BMP support
601 CONFIG_CMD_BSP * Board specific commands
602 CONFIG_CMD_BOOTD bootd
603 CONFIG_CMD_CACHE * icache, dcache
604 CONFIG_CMD_CONSOLE coninfo
605 CONFIG_CMD_DATE * support for RTC, date/time...
606 CONFIG_CMD_DHCP * DHCP support
607 CONFIG_CMD_DIAG * Diagnostics
608 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
609 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
610 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
611 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
612 CONFIG_CMD_DTT * Digital Therm and Thermostat
613 CONFIG_CMD_ECHO echo arguments
614 CONFIG_CMD_EEPROM * EEPROM read/write support
615 CONFIG_CMD_ELF * bootelf, bootvx
616 CONFIG_CMD_SAVEENV saveenv
617 CONFIG_CMD_FDC * Floppy Disk Support
618 CONFIG_CMD_FAT * FAT partition support
619 CONFIG_CMD_FDOS * Dos diskette Support
620 CONFIG_CMD_FLASH flinfo, erase, protect
621 CONFIG_CMD_FPGA FPGA device initialization support
622 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
623 CONFIG_CMD_I2C * I2C serial bus support
624 CONFIG_CMD_IDE * IDE harddisk support
625 CONFIG_CMD_IMI iminfo
626 CONFIG_CMD_IMLS List all found images
627 CONFIG_CMD_IMMAP * IMMR dump support
628 CONFIG_CMD_IRQ * irqinfo
629 CONFIG_CMD_ITEST Integer/string test of 2 values
630 CONFIG_CMD_JFFS2 * JFFS2 Support
631 CONFIG_CMD_KGDB * kgdb
632 CONFIG_CMD_LOADB loadb
633 CONFIG_CMD_LOADS loads
634 CONFIG_CMD_MD5SUM print md5 message digest
635 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
636 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
638 CONFIG_CMD_MISC Misc functions like sleep etc
639 CONFIG_CMD_MMC * MMC memory mapped support
640 CONFIG_CMD_MII * MII utility commands
641 CONFIG_CMD_MTDPARTS * MTD partition support
642 CONFIG_CMD_NAND * NAND support
643 CONFIG_CMD_NET bootp, tftpboot, rarpboot
644 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
645 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
646 CONFIG_CMD_PCI * pciinfo
647 CONFIG_CMD_PCMCIA * PCMCIA support
648 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
650 CONFIG_CMD_PORTIO * Port I/O
651 CONFIG_CMD_REGINFO * Register dump
652 CONFIG_CMD_RUN run command in env variable
653 CONFIG_CMD_SAVES * save S record dump
654 CONFIG_CMD_SCSI * SCSI Support
655 CONFIG_CMD_SDRAM * print SDRAM configuration information
656 (requires CONFIG_CMD_I2C)
657 CONFIG_CMD_SETGETDCR Support for DCR Register access
659 CONFIG_CMD_SHA1 print sha1 memory digest
660 (requires CONFIG_CMD_MEMORY)
661 CONFIG_CMD_SOURCE "source" command Support
662 CONFIG_CMD_SPI * SPI serial bus support
663 CONFIG_CMD_USB * USB support
664 CONFIG_CMD_VFD * VFD support (TRAB)
665 CONFIG_CMD_CDP * Cisco Discover Protocol support
666 CONFIG_CMD_FSL * Microblaze FSL support
669 EXAMPLE: If you want all functions except of network
670 support you can write:
672 #include "config_cmd_all.h"
673 #undef CONFIG_CMD_NET
676 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
678 Note: Don't enable the "icache" and "dcache" commands
679 (configuration option CONFIG_CMD_CACHE) unless you know
680 what you (and your U-Boot users) are doing. Data
681 cache cannot be enabled on systems like the 8xx or
682 8260 (where accesses to the IMMR region must be
683 uncached), and it cannot be disabled on all other
684 systems where we (mis-) use the data cache to hold an
685 initial stack and some data.
688 XXX - this list needs to get updated!
692 If this variable is defined, it enables watchdog
693 support. There must be support in the platform specific
694 code for a watchdog. For the 8xx and 8260 CPUs, the
695 SIU Watchdog feature is enabled in the SYPCR
699 CONFIG_VERSION_VARIABLE
700 If this variable is defined, an environment variable
701 named "ver" is created by U-Boot showing the U-Boot
702 version as printed by the "version" command.
703 This variable is readonly.
707 When CONFIG_CMD_DATE is selected, the type of the RTC
708 has to be selected, too. Define exactly one of the
711 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
712 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
713 CONFIG_RTC_MC13783 - use MC13783 RTC
714 CONFIG_RTC_MC146818 - use MC146818 RTC
715 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
716 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
717 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
718 CONFIG_RTC_DS164x - use Dallas DS164x RTC
719 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
720 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
721 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
723 Note that if the RTC uses I2C, then the I2C interface
724 must also be configured. See I2C Support, below.
727 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
728 CONFIG_PCA953X_INFO - enable pca953x info command
730 Note that if the GPIO device uses I2C, then the I2C interface
731 must also be configured. See I2C Support, below.
735 When CONFIG_TIMESTAMP is selected, the timestamp
736 (date and time) of an image is printed by image
737 commands like bootm or iminfo. This option is
738 automatically enabled when you select CONFIG_CMD_DATE .
741 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
742 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
744 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
745 CONFIG_CMD_SCSI) you must configure support for at
746 least one partition type as well.
749 CONFIG_IDE_RESET_ROUTINE - this is defined in several
750 board configurations files but used nowhere!
752 CONFIG_IDE_RESET - is this is defined, IDE Reset will
753 be performed by calling the function
754 ide_set_reset(int reset)
755 which has to be defined in a board specific file
760 Set this to enable ATAPI support.
765 Set this to enable support for disks larger than 137GB
766 Also look at CONFIG_SYS_64BIT_LBA ,CONFIG_SYS_64BIT_VSPRINTF and CONFIG_SYS_64BIT_STRTOUL
767 Whithout these , LBA48 support uses 32bit variables and will 'only'
768 support disks up to 2.1TB.
770 CONFIG_SYS_64BIT_LBA:
771 When enabled, makes the IDE subsystem use 64bit sector addresses.
775 At the moment only there is only support for the
776 SYM53C8XX SCSI controller; define
777 CONFIG_SCSI_SYM53C8XX to enable it.
779 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
780 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
781 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
782 maximum numbers of LUNs, SCSI ID's and target
784 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
786 - NETWORK Support (PCI):
788 Support for Intel 8254x gigabit chips.
790 CONFIG_E1000_FALLBACK_MAC
791 default MAC for empty EEPROM after production.
794 Support for Intel 82557/82559/82559ER chips.
795 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
796 write routine for first time initialisation.
799 Support for Digital 2114x chips.
800 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
801 modem chip initialisation (KS8761/QS6611).
804 Support for National dp83815 chips.
807 Support for National dp8382[01] gigabit chips.
809 - NETWORK Support (other):
811 CONFIG_DRIVER_LAN91C96
812 Support for SMSC's LAN91C96 chips.
815 Define this to hold the physical address
816 of the LAN91C96's I/O space
818 CONFIG_LAN91C96_USE_32_BIT
819 Define this to enable 32 bit addressing
821 CONFIG_DRIVER_SMC91111
822 Support for SMSC's LAN91C111 chip
825 Define this to hold the physical address
826 of the device (I/O space)
828 CONFIG_SMC_USE_32_BIT
829 Define this if data bus is 32 bits
831 CONFIG_SMC_USE_IOFUNCS
832 Define this to use i/o functions instead of macros
833 (some hardware wont work with macros)
835 CONFIG_DRIVER_SMC911X
836 Support for SMSC's LAN911x and LAN921x chips
838 CONFIG_DRIVER_SMC911X_BASE
839 Define this to hold the physical address
840 of the device (I/O space)
842 CONFIG_DRIVER_SMC911X_32_BIT
843 Define this if data bus is 32 bits
845 CONFIG_DRIVER_SMC911X_16_BIT
846 Define this if data bus is 16 bits. If your processor
847 automatically converts one 32 bit word to two 16 bit
848 words you may also try CONFIG_DRIVER_SMC911X_32_BIT.
851 At the moment only the UHCI host controller is
852 supported (PIP405, MIP405, MPC5200); define
853 CONFIG_USB_UHCI to enable it.
854 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
855 and define CONFIG_USB_STORAGE to enable the USB
858 Supported are USB Keyboards and USB Floppy drives
860 MPC5200 USB requires additional defines:
862 for 528 MHz Clock: 0x0001bbbb
866 for differential drivers: 0x00001000
867 for single ended drivers: 0x00005000
868 for differential drivers on PSC3: 0x00000100
869 for single ended drivers on PSC3: 0x00004100
870 CONFIG_SYS_USB_EVENT_POLL
871 May be defined to allow interrupt polling
872 instead of using asynchronous interrupts
875 Define the below if you wish to use the USB console.
876 Once firmware is rebuilt from a serial console issue the
877 command "setenv stdin usbtty; setenv stdout usbtty" and
878 attach your USB cable. The Unix command "dmesg" should print
879 it has found a new device. The environment variable usbtty
880 can be set to gserial or cdc_acm to enable your device to
881 appear to a USB host as a Linux gserial device or a
882 Common Device Class Abstract Control Model serial device.
883 If you select usbtty = gserial you should be able to enumerate
885 # modprobe usbserial vendor=0xVendorID product=0xProductID
886 else if using cdc_acm, simply setting the environment
887 variable usbtty to be cdc_acm should suffice. The following
888 might be defined in YourBoardName.h
891 Define this to build a UDC device
894 Define this to have a tty type of device available to
895 talk to the UDC device
897 CONFIG_SYS_CONSOLE_IS_IN_ENV
898 Define this if you want stdin, stdout &/or stderr to
902 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
903 Derive USB clock from external clock "blah"
904 - CONFIG_SYS_USB_EXTC_CLK 0x02
906 CONFIG_SYS_USB_BRG_CLK 0xBLAH
907 Derive USB clock from brgclk
908 - CONFIG_SYS_USB_BRG_CLK 0x04
910 If you have a USB-IF assigned VendorID then you may wish to
911 define your own vendor specific values either in BoardName.h
912 or directly in usbd_vendor_info.h. If you don't define
913 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
914 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
915 should pretend to be a Linux device to it's target host.
917 CONFIG_USBD_MANUFACTURER
918 Define this string as the name of your company for
919 - CONFIG_USBD_MANUFACTURER "my company"
921 CONFIG_USBD_PRODUCT_NAME
922 Define this string as the name of your product
923 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
926 Define this as your assigned Vendor ID from the USB
927 Implementors Forum. This *must* be a genuine Vendor ID
928 to avoid polluting the USB namespace.
929 - CONFIG_USBD_VENDORID 0xFFFF
931 CONFIG_USBD_PRODUCTID
932 Define this as the unique Product ID
934 - CONFIG_USBD_PRODUCTID 0xFFFF
938 The MMC controller on the Intel PXA is supported. To
939 enable this define CONFIG_MMC. The MMC can be
940 accessed from the boot prompt by mapping the device
941 to physical memory similar to flash. Command line is
942 enabled with CONFIG_CMD_MMC. The MMC driver also works with
943 the FAT fs. This is enabled with CONFIG_CMD_FAT.
945 - Journaling Flash filesystem support:
946 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
947 CONFIG_JFFS2_NAND_DEV
948 Define these for a default partition on a NAND device
950 CONFIG_SYS_JFFS2_FIRST_SECTOR,
951 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
952 Define these for a default partition on a NOR device
954 CONFIG_SYS_JFFS_CUSTOM_PART
955 Define this to create an own partition. You have to provide a
956 function struct part_info* jffs2_part_info(int part_num)
958 If you define only one JFFS2 partition you may also want to
959 #define CONFIG_SYS_JFFS_SINGLE_PART 1
960 to disable the command chpart. This is the default when you
961 have not defined a custom partition
966 Define this to enable standard (PC-Style) keyboard
970 Standard PC keyboard driver with US (is default) and
971 GERMAN key layout (switch via environment 'keymap=de') support.
972 Export function i8042_kbd_init, i8042_tstc and i8042_getc
973 for cfb_console. Supports cursor blinking.
978 Define this to enable video support (for output to
983 Enable Chips & Technologies 69000 Video chip
985 CONFIG_VIDEO_SMI_LYNXEM
986 Enable Silicon Motion SMI 712/710/810 Video chip. The
987 video output is selected via environment 'videoout'
988 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
991 For the CT69000 and SMI_LYNXEM drivers, videomode is
992 selected via environment 'videomode'. Two different ways
994 - "videomode=num" 'num' is a standard LiLo mode numbers.
995 Following standard modes are supported (* is default):
997 Colors 640x480 800x600 1024x768 1152x864 1280x1024
998 -------------+---------------------------------------------
999 8 bits | 0x301* 0x303 0x305 0x161 0x307
1000 15 bits | 0x310 0x313 0x316 0x162 0x319
1001 16 bits | 0x311 0x314 0x317 0x163 0x31A
1002 24 bits | 0x312 0x315 0x318 ? 0x31B
1003 -------------+---------------------------------------------
1004 (i.e. setenv videomode 317; saveenv; reset;)
1006 - "videomode=bootargs" all the video parameters are parsed
1007 from the bootargs. (See drivers/video/videomodes.c)
1010 CONFIG_VIDEO_SED13806
1011 Enable Epson SED13806 driver. This driver supports 8bpp
1012 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1013 or CONFIG_VIDEO_SED13806_16BPP
1018 Define this to enable a custom keyboard support.
1019 This simply calls drv_keyboard_init() which must be
1020 defined in your board-specific files.
1021 The only board using this so far is RBC823.
1023 - LCD Support: CONFIG_LCD
1025 Define this to enable LCD support (for output to LCD
1026 display); also select one of the supported displays
1027 by defining one of these:
1031 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1033 CONFIG_NEC_NL6448AC33:
1035 NEC NL6448AC33-18. Active, color, single scan.
1037 CONFIG_NEC_NL6448BC20
1039 NEC NL6448BC20-08. 6.5", 640x480.
1040 Active, color, single scan.
1042 CONFIG_NEC_NL6448BC33_54
1044 NEC NL6448BC33-54. 10.4", 640x480.
1045 Active, color, single scan.
1049 Sharp 320x240. Active, color, single scan.
1050 It isn't 16x9, and I am not sure what it is.
1052 CONFIG_SHARP_LQ64D341
1054 Sharp LQ64D341 display, 640x480.
1055 Active, color, single scan.
1059 HLD1045 display, 640x480.
1060 Active, color, single scan.
1064 Optrex CBL50840-2 NF-FW 99 22 M5
1066 Hitachi LMG6912RPFC-00T
1070 320x240. Black & white.
1072 Normally display is black on white background; define
1073 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1075 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1077 If this option is set, the environment is checked for
1078 a variable "splashimage". If found, the usual display
1079 of logo, copyright and system information on the LCD
1080 is suppressed and the BMP image at the address
1081 specified in "splashimage" is loaded instead. The
1082 console is redirected to the "nulldev", too. This
1083 allows for a "silent" boot where a splash screen is
1084 loaded very quickly after power-on.
1086 CONFIG_SPLASH_SCREEN_ALIGN
1088 If this option is set the splash image can be freely positioned
1089 on the screen. Environment variable "splashpos" specifies the
1090 position as "x,y". If a positive number is given it is used as
1091 number of pixel from left/top. If a negative number is given it
1092 is used as number of pixel from right/bottom. You can also
1093 specify 'm' for centering the image.
1096 setenv splashpos m,m
1097 => image at center of screen
1099 setenv splashpos 30,20
1100 => image at x = 30 and y = 20
1102 setenv splashpos -10,m
1103 => vertically centered image
1104 at x = dspWidth - bmpWidth - 9
1106 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1108 If this option is set, additionally to standard BMP
1109 images, gzipped BMP images can be displayed via the
1110 splashscreen support or the bmp command.
1112 - Compression support:
1115 If this option is set, support for bzip2 compressed
1116 images is included. If not, only uncompressed and gzip
1117 compressed images are supported.
1119 NOTE: the bzip2 algorithm requires a lot of RAM, so
1120 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1125 If this option is set, support for lzma compressed
1128 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1129 requires an amount of dynamic memory that is given by the
1132 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1134 Where lc and lp stand for, respectively, Literal context bits
1135 and Literal pos bits.
1137 This value is upper-bounded by 14MB in the worst case. Anyway,
1138 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1139 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1140 a very small buffer.
1142 Use the lzmainfo tool to determinate the lc and lp values and
1143 then calculate the amount of needed dynamic memory (ensuring
1144 the appropriate CONFIG_SYS_MALLOC_LEN value).
1149 The address of PHY on MII bus.
1151 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1153 The clock frequency of the MII bus
1157 If this option is set, support for speed/duplex
1158 detection of gigabit PHY is included.
1160 CONFIG_PHY_RESET_DELAY
1162 Some PHY like Intel LXT971A need extra delay after
1163 reset before any MII register access is possible.
1164 For such PHY, set this option to the usec delay
1165 required. (minimum 300usec for LXT971A)
1167 CONFIG_PHY_CMD_DELAY (ppc4xx)
1169 Some PHY like Intel LXT971A need extra delay after
1170 command issued before MII status register can be read
1180 Define a default value for Ethernet address to use
1181 for the respective Ethernet interface, in case this
1182 is not determined automatically.
1187 Define a default value for the IP address to use for
1188 the default Ethernet interface, in case this is not
1189 determined through e.g. bootp.
1191 - Server IP address:
1194 Defines a default value for the IP address of a TFTP
1195 server to contact when using the "tftboot" command.
1197 CONFIG_KEEP_SERVERADDR
1199 Keeps the server's MAC address, in the env 'serveraddr'
1200 for passing to bootargs (like Linux's netconsole option)
1202 - Multicast TFTP Mode:
1205 Defines whether you want to support multicast TFTP as per
1206 rfc-2090; for example to work with atftp. Lets lots of targets
1207 tftp down the same boot image concurrently. Note: the Ethernet
1208 driver in use must provide a function: mcast() to join/leave a
1211 CONFIG_BOOTP_RANDOM_DELAY
1212 - BOOTP Recovery Mode:
1213 CONFIG_BOOTP_RANDOM_DELAY
1215 If you have many targets in a network that try to
1216 boot using BOOTP, you may want to avoid that all
1217 systems send out BOOTP requests at precisely the same
1218 moment (which would happen for instance at recovery
1219 from a power failure, when all systems will try to
1220 boot, thus flooding the BOOTP server. Defining
1221 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1222 inserted before sending out BOOTP requests. The
1223 following delays are inserted then:
1225 1st BOOTP request: delay 0 ... 1 sec
1226 2nd BOOTP request: delay 0 ... 2 sec
1227 3rd BOOTP request: delay 0 ... 4 sec
1229 BOOTP requests: delay 0 ... 8 sec
1231 - DHCP Advanced Options:
1232 You can fine tune the DHCP functionality by defining
1233 CONFIG_BOOTP_* symbols:
1235 CONFIG_BOOTP_SUBNETMASK
1236 CONFIG_BOOTP_GATEWAY
1237 CONFIG_BOOTP_HOSTNAME
1238 CONFIG_BOOTP_NISDOMAIN
1239 CONFIG_BOOTP_BOOTPATH
1240 CONFIG_BOOTP_BOOTFILESIZE
1243 CONFIG_BOOTP_SEND_HOSTNAME
1244 CONFIG_BOOTP_NTPSERVER
1245 CONFIG_BOOTP_TIMEOFFSET
1246 CONFIG_BOOTP_VENDOREX
1248 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1249 environment variable, not the BOOTP server.
1251 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1252 serverip from a DHCP server, it is possible that more
1253 than one DNS serverip is offered to the client.
1254 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1255 serverip will be stored in the additional environment
1256 variable "dnsip2". The first DNS serverip is always
1257 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1260 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1261 to do a dynamic update of a DNS server. To do this, they
1262 need the hostname of the DHCP requester.
1263 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1264 of the "hostname" environment variable is passed as
1265 option 12 to the DHCP server.
1267 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1269 A 32bit value in microseconds for a delay between
1270 receiving a "DHCP Offer" and sending the "DHCP Request".
1271 This fixes a problem with certain DHCP servers that don't
1272 respond 100% of the time to a "DHCP request". E.g. On an
1273 AT91RM9200 processor running at 180MHz, this delay needed
1274 to be *at least* 15,000 usec before a Windows Server 2003
1275 DHCP server would reply 100% of the time. I recommend at
1276 least 50,000 usec to be safe. The alternative is to hope
1277 that one of the retries will be successful but note that
1278 the DHCP timeout and retry process takes a longer than
1282 CONFIG_CDP_DEVICE_ID
1284 The device id used in CDP trigger frames.
1286 CONFIG_CDP_DEVICE_ID_PREFIX
1288 A two character string which is prefixed to the MAC address
1293 A printf format string which contains the ascii name of
1294 the port. Normally is set to "eth%d" which sets
1295 eth0 for the first Ethernet, eth1 for the second etc.
1297 CONFIG_CDP_CAPABILITIES
1299 A 32bit integer which indicates the device capabilities;
1300 0x00000010 for a normal host which does not forwards.
1304 An ascii string containing the version of the software.
1308 An ascii string containing the name of the platform.
1312 A 32bit integer sent on the trigger.
1314 CONFIG_CDP_POWER_CONSUMPTION
1316 A 16bit integer containing the power consumption of the
1317 device in .1 of milliwatts.
1319 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1321 A byte containing the id of the VLAN.
1323 - Status LED: CONFIG_STATUS_LED
1325 Several configurations allow to display the current
1326 status using a LED. For instance, the LED will blink
1327 fast while running U-Boot code, stop blinking as
1328 soon as a reply to a BOOTP request was received, and
1329 start blinking slow once the Linux kernel is running
1330 (supported by a status LED driver in the Linux
1331 kernel). Defining CONFIG_STATUS_LED enables this
1334 - CAN Support: CONFIG_CAN_DRIVER
1336 Defining CONFIG_CAN_DRIVER enables CAN driver support
1337 on those systems that support this (optional)
1338 feature, like the TQM8xxL modules.
1340 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1342 These enable I2C serial bus commands. Defining either of
1343 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1344 include the appropriate I2C driver for the selected CPU.
1346 This will allow you to use i2c commands at the u-boot
1347 command line (as long as you set CONFIG_CMD_I2C in
1348 CONFIG_COMMANDS) and communicate with i2c based realtime
1349 clock chips. See common/cmd_i2c.c for a description of the
1350 command line interface.
1352 CONFIG_HARD_I2C selects a hardware I2C controller.
1354 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1355 bit-banging) driver instead of CPM or similar hardware
1358 There are several other quantities that must also be
1359 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1361 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1362 to be the frequency (in Hz) at which you wish your i2c bus
1363 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1364 the CPU's i2c node address).
1366 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1367 sets the CPU up as a master node and so its address should
1368 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1369 p.16-473). So, set CONFIG_SYS_I2C_SLAVE to 0.
1371 CONFIG_SYS_I2C_INIT_MPC5XXX
1373 When a board is reset during an i2c bus transfer
1374 chips might think that the current transfer is still
1375 in progress. Reset the slave devices by sending start
1376 commands until the slave device responds.
1378 That's all that's required for CONFIG_HARD_I2C.
1380 If you use the software i2c interface (CONFIG_SOFT_I2C)
1381 then the following macros need to be defined (examples are
1382 from include/configs/lwmon.h):
1386 (Optional). Any commands necessary to enable the I2C
1387 controller or configure ports.
1389 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1393 (Only for MPC8260 CPU). The I/O port to use (the code
1394 assumes both bits are on the same port). Valid values
1395 are 0..3 for ports A..D.
1399 The code necessary to make the I2C data line active
1400 (driven). If the data line is open collector, this
1403 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1407 The code necessary to make the I2C data line tri-stated
1408 (inactive). If the data line is open collector, this
1411 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1415 Code that returns TRUE if the I2C data line is high,
1418 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1422 If <bit> is TRUE, sets the I2C data line high. If it
1423 is FALSE, it clears it (low).
1425 eg: #define I2C_SDA(bit) \
1426 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1427 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1431 If <bit> is TRUE, sets the I2C clock line high. If it
1432 is FALSE, it clears it (low).
1434 eg: #define I2C_SCL(bit) \
1435 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1436 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1440 This delay is invoked four times per clock cycle so this
1441 controls the rate of data transfer. The data rate thus
1442 is 1 / (I2C_DELAY * 4). Often defined to be something
1445 #define I2C_DELAY udelay(2)
1447 CONFIG_SYS_I2C_INIT_BOARD
1449 When a board is reset during an i2c bus transfer
1450 chips might think that the current transfer is still
1451 in progress. On some boards it is possible to access
1452 the i2c SCLK line directly, either by using the
1453 processor pin as a GPIO or by having a second pin
1454 connected to the bus. If this option is defined a
1455 custom i2c_init_board() routine in boards/xxx/board.c
1456 is run early in the boot sequence.
1458 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1460 This option enables configuration of bi_iic_fast[] flags
1461 in u-boot bd_info structure based on u-boot environment
1462 variable "i2cfast". (see also i2cfast)
1464 CONFIG_I2C_MULTI_BUS
1466 This option allows the use of multiple I2C buses, each of which
1467 must have a controller. At any point in time, only one bus is
1468 active. To switch to a different bus, use the 'i2c dev' command.
1469 Note that bus numbering is zero-based.
1471 CONFIG_SYS_I2C_NOPROBES
1473 This option specifies a list of I2C devices that will be skipped
1474 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1475 is set, specify a list of bus-device pairs. Otherwise, specify
1476 a 1D array of device addresses
1479 #undef CONFIG_I2C_MULTI_BUS
1480 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1482 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1484 #define CONFIG_I2C_MULTI_BUS
1485 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1487 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1489 CONFIG_SYS_SPD_BUS_NUM
1491 If defined, then this indicates the I2C bus number for DDR SPD.
1492 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1494 CONFIG_SYS_RTC_BUS_NUM
1496 If defined, then this indicates the I2C bus number for the RTC.
1497 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1499 CONFIG_SYS_DTT_BUS_NUM
1501 If defined, then this indicates the I2C bus number for the DTT.
1502 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1504 CONFIG_SYS_I2C_DTT_ADDR:
1506 If defined, specifies the I2C address of the DTT device.
1507 If not defined, then U-Boot uses predefined value for
1508 specified DTT device.
1512 Define this option if you want to use Freescale's I2C driver in
1513 drivers/i2c/fsl_i2c.c.
1517 Define this option if you have I2C devices reached over 1 .. n
1518 I2C Muxes like the pca9544a. This option addes a new I2C
1519 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1520 new I2C Bus to the existing I2C Busses. If you select the
1521 new Bus with "i2c dev", u-bbot sends first the commandos for
1522 the muxes to activate this new "bus".
1524 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1528 Adding a new I2C Bus reached over 2 pca9544a muxes
1529 The First mux with address 70 and channel 6
1530 The Second mux with address 71 and channel 4
1532 => i2c bus pca9544a:70:6:pca9544a:71:4
1534 Use the "i2c bus" command without parameter, to get a list
1535 of I2C Busses with muxes:
1538 Busses reached over muxes:
1540 reached over Mux(es):
1543 reached over Mux(es):
1548 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1549 u-boot sends First the Commando to the mux@70 to enable
1550 channel 6, and then the Commando to the mux@71 to enable
1553 After that, you can use the "normal" i2c commands as
1554 usual, to communicate with your I2C devices behind
1557 This option is actually implemented for the bitbanging
1558 algorithm in common/soft_i2c.c and for the Hardware I2C
1559 Bus on the MPC8260. But it should be not so difficult
1560 to add this option to other architectures.
1562 CONFIG_SOFT_I2C_READ_REPEATED_START
1564 defining this will force the i2c_read() function in
1565 the soft_i2c driver to perform an I2C repeated start
1566 between writing the address pointer and reading the
1567 data. If this define is omitted the default behaviour
1568 of doing a stop-start sequence will be used. Most I2C
1569 devices can use either method, but some require one or
1572 - SPI Support: CONFIG_SPI
1574 Enables SPI driver (so far only tested with
1575 SPI EEPROM, also an instance works with Crystal A/D and
1576 D/As on the SACSng board)
1580 Enables extended (16-bit) SPI EEPROM addressing.
1581 (symmetrical to CONFIG_I2C_X)
1585 Enables a software (bit-bang) SPI driver rather than
1586 using hardware support. This is a general purpose
1587 driver that only requires three general I/O port pins
1588 (two outputs, one input) to function. If this is
1589 defined, the board configuration must define several
1590 SPI configuration items (port pins to use, etc). For
1591 an example, see include/configs/sacsng.h.
1595 Enables a hardware SPI driver for general-purpose reads
1596 and writes. As with CONFIG_SOFT_SPI, the board configuration
1597 must define a list of chip-select function pointers.
1598 Currently supported on some MPC8xxx processors. For an
1599 example, see include/configs/mpc8349emds.h.
1603 Enables the driver for the SPI controllers on i.MX and MXC
1604 SoCs. Currently only i.MX31 is supported.
1606 - FPGA Support: CONFIG_FPGA
1608 Enables FPGA subsystem.
1610 CONFIG_FPGA_<vendor>
1612 Enables support for specific chip vendors.
1615 CONFIG_FPGA_<family>
1617 Enables support for FPGA family.
1618 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1622 Specify the number of FPGA devices to support.
1624 CONFIG_SYS_FPGA_PROG_FEEDBACK
1626 Enable printing of hash marks during FPGA configuration.
1628 CONFIG_SYS_FPGA_CHECK_BUSY
1630 Enable checks on FPGA configuration interface busy
1631 status by the configuration function. This option
1632 will require a board or device specific function to
1637 If defined, a function that provides delays in the FPGA
1638 configuration driver.
1640 CONFIG_SYS_FPGA_CHECK_CTRLC
1641 Allow Control-C to interrupt FPGA configuration
1643 CONFIG_SYS_FPGA_CHECK_ERROR
1645 Check for configuration errors during FPGA bitfile
1646 loading. For example, abort during Virtex II
1647 configuration if the INIT_B line goes low (which
1648 indicated a CRC error).
1650 CONFIG_SYS_FPGA_WAIT_INIT
1652 Maximum time to wait for the INIT_B line to deassert
1653 after PROB_B has been deasserted during a Virtex II
1654 FPGA configuration sequence. The default time is 500
1657 CONFIG_SYS_FPGA_WAIT_BUSY
1659 Maximum time to wait for BUSY to deassert during
1660 Virtex II FPGA configuration. The default is 5 ms.
1662 CONFIG_SYS_FPGA_WAIT_CONFIG
1664 Time to wait after FPGA configuration. The default is
1667 - Configuration Management:
1670 If defined, this string will be added to the U-Boot
1671 version information (U_BOOT_VERSION)
1673 - Vendor Parameter Protection:
1675 U-Boot considers the values of the environment
1676 variables "serial#" (Board Serial Number) and
1677 "ethaddr" (Ethernet Address) to be parameters that
1678 are set once by the board vendor / manufacturer, and
1679 protects these variables from casual modification by
1680 the user. Once set, these variables are read-only,
1681 and write or delete attempts are rejected. You can
1682 change this behaviour:
1684 If CONFIG_ENV_OVERWRITE is #defined in your config
1685 file, the write protection for vendor parameters is
1686 completely disabled. Anybody can change or delete
1689 Alternatively, if you #define _both_ CONFIG_ETHADDR
1690 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1691 Ethernet address is installed in the environment,
1692 which can be changed exactly ONCE by the user. [The
1693 serial# is unaffected by this, i. e. it remains
1699 Define this variable to enable the reservation of
1700 "protected RAM", i. e. RAM which is not overwritten
1701 by U-Boot. Define CONFIG_PRAM to hold the number of
1702 kB you want to reserve for pRAM. You can overwrite
1703 this default value by defining an environment
1704 variable "pram" to the number of kB you want to
1705 reserve. Note that the board info structure will
1706 still show the full amount of RAM. If pRAM is
1707 reserved, a new environment variable "mem" will
1708 automatically be defined to hold the amount of
1709 remaining RAM in a form that can be passed as boot
1710 argument to Linux, for instance like that:
1712 setenv bootargs ... mem=\${mem}
1715 This way you can tell Linux not to use this memory,
1716 either, which results in a memory region that will
1717 not be affected by reboots.
1719 *WARNING* If your board configuration uses automatic
1720 detection of the RAM size, you must make sure that
1721 this memory test is non-destructive. So far, the
1722 following board configurations are known to be
1725 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1726 HERMES, IP860, RPXlite, LWMON, LANTEC,
1727 PCU_E, FLAGADM, TQM8260
1732 Define this variable to stop the system in case of a
1733 fatal error, so that you have to reset it manually.
1734 This is probably NOT a good idea for an embedded
1735 system where you want the system to reboot
1736 automatically as fast as possible, but it may be
1737 useful during development since you can try to debug
1738 the conditions that lead to the situation.
1740 CONFIG_NET_RETRY_COUNT
1742 This variable defines the number of retries for
1743 network operations like ARP, RARP, TFTP, or BOOTP
1744 before giving up the operation. If not defined, a
1745 default value of 5 is used.
1749 Timeout waiting for an ARP reply in milliseconds.
1751 - Command Interpreter:
1752 CONFIG_AUTO_COMPLETE
1754 Enable auto completion of commands using TAB.
1756 Note that this feature has NOT been implemented yet
1757 for the "hush" shell.
1760 CONFIG_SYS_HUSH_PARSER
1762 Define this variable to enable the "hush" shell (from
1763 Busybox) as command line interpreter, thus enabling
1764 powerful command line syntax like
1765 if...then...else...fi conditionals or `&&' and '||'
1766 constructs ("shell scripts").
1768 If undefined, you get the old, much simpler behaviour
1769 with a somewhat smaller memory footprint.
1772 CONFIG_SYS_PROMPT_HUSH_PS2
1774 This defines the secondary prompt string, which is
1775 printed when the command interpreter needs more input
1776 to complete a command. Usually "> ".
1780 In the current implementation, the local variables
1781 space and global environment variables space are
1782 separated. Local variables are those you define by
1783 simply typing `name=value'. To access a local
1784 variable later on, you have write `$name' or
1785 `${name}'; to execute the contents of a variable
1786 directly type `$name' at the command prompt.
1788 Global environment variables are those you use
1789 setenv/printenv to work with. To run a command stored
1790 in such a variable, you need to use the run command,
1791 and you must not use the '$' sign to access them.
1793 To store commands and special characters in a
1794 variable, please use double quotation marks
1795 surrounding the whole text of the variable, instead
1796 of the backslashes before semicolons and special
1799 - Commandline Editing and History:
1800 CONFIG_CMDLINE_EDITING
1802 Enable editing and History functions for interactive
1803 commandline input operations
1805 - Default Environment:
1806 CONFIG_EXTRA_ENV_SETTINGS
1808 Define this to contain any number of null terminated
1809 strings (variable = value pairs) that will be part of
1810 the default environment compiled into the boot image.
1812 For example, place something like this in your
1813 board's config file:
1815 #define CONFIG_EXTRA_ENV_SETTINGS \
1819 Warning: This method is based on knowledge about the
1820 internal format how the environment is stored by the
1821 U-Boot code. This is NOT an official, exported
1822 interface! Although it is unlikely that this format
1823 will change soon, there is no guarantee either.
1824 You better know what you are doing here.
1826 Note: overly (ab)use of the default environment is
1827 discouraged. Make sure to check other ways to preset
1828 the environment like the "source" command or the
1831 - DataFlash Support:
1832 CONFIG_HAS_DATAFLASH
1834 Defining this option enables DataFlash features and
1835 allows to read/write in Dataflash via the standard
1838 - SystemACE Support:
1841 Adding this option adds support for Xilinx SystemACE
1842 chips attached via some sort of local bus. The address
1843 of the chip must also be defined in the
1844 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
1846 #define CONFIG_SYSTEMACE
1847 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
1849 When SystemACE support is added, the "ace" device type
1850 becomes available to the fat commands, i.e. fatls.
1852 - TFTP Fixed UDP Port:
1855 If this is defined, the environment variable tftpsrcp
1856 is used to supply the TFTP UDP source port value.
1857 If tftpsrcp isn't defined, the normal pseudo-random port
1858 number generator is used.
1860 Also, the environment variable tftpdstp is used to supply
1861 the TFTP UDP destination port value. If tftpdstp isn't
1862 defined, the normal port 69 is used.
1864 The purpose for tftpsrcp is to allow a TFTP server to
1865 blindly start the TFTP transfer using the pre-configured
1866 target IP address and UDP port. This has the effect of
1867 "punching through" the (Windows XP) firewall, allowing
1868 the remainder of the TFTP transfer to proceed normally.
1869 A better solution is to properly configure the firewall,
1870 but sometimes that is not allowed.
1872 - Show boot progress:
1873 CONFIG_SHOW_BOOT_PROGRESS
1875 Defining this option allows to add some board-
1876 specific code (calling a user-provided function
1877 "show_boot_progress(int)") that enables you to show
1878 the system's boot progress on some display (for
1879 example, some LED's) on your board. At the moment,
1880 the following checkpoints are implemented:
1882 - Automatic software updates via TFTP server
1884 CONFIG_UPDATE_TFTP_CNT_MAX
1885 CONFIG_UPDATE_TFTP_MSEC_MAX
1887 These options enable and control the auto-update feature;
1888 for a more detailed description refer to doc/README.update.
1890 - MTD Support (mtdparts command, UBI support)
1893 Adds the MTD device infrastructure from the Linux kernel.
1894 Needed for mtdparts command support.
1896 CONFIG_MTD_PARTITIONS
1898 Adds the MTD partitioning infrastructure from the Linux
1899 kernel. Needed for UBI support.
1901 Legacy uImage format:
1904 1 common/cmd_bootm.c before attempting to boot an image
1905 -1 common/cmd_bootm.c Image header has bad magic number
1906 2 common/cmd_bootm.c Image header has correct magic number
1907 -2 common/cmd_bootm.c Image header has bad checksum
1908 3 common/cmd_bootm.c Image header has correct checksum
1909 -3 common/cmd_bootm.c Image data has bad checksum
1910 4 common/cmd_bootm.c Image data has correct checksum
1911 -4 common/cmd_bootm.c Image is for unsupported architecture
1912 5 common/cmd_bootm.c Architecture check OK
1913 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
1914 6 common/cmd_bootm.c Image Type check OK
1915 -6 common/cmd_bootm.c gunzip uncompression error
1916 -7 common/cmd_bootm.c Unimplemented compression type
1917 7 common/cmd_bootm.c Uncompression OK
1918 8 common/cmd_bootm.c No uncompress/copy overwrite error
1919 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1921 9 common/image.c Start initial ramdisk verification
1922 -10 common/image.c Ramdisk header has bad magic number
1923 -11 common/image.c Ramdisk header has bad checksum
1924 10 common/image.c Ramdisk header is OK
1925 -12 common/image.c Ramdisk data has bad checksum
1926 11 common/image.c Ramdisk data has correct checksum
1927 12 common/image.c Ramdisk verification complete, start loading
1928 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
1929 13 common/image.c Start multifile image verification
1930 14 common/image.c No initial ramdisk, no multifile, continue.
1932 15 lib_<arch>/bootm.c All preparation done, transferring control to OS
1934 -30 lib_ppc/board.c Fatal error, hang the system
1935 -31 post/post.c POST test failed, detected by post_output_backlog()
1936 -32 post/post.c POST test failed, detected by post_run_single()
1938 34 common/cmd_doc.c before loading a Image from a DOC device
1939 -35 common/cmd_doc.c Bad usage of "doc" command
1940 35 common/cmd_doc.c correct usage of "doc" command
1941 -36 common/cmd_doc.c No boot device
1942 36 common/cmd_doc.c correct boot device
1943 -37 common/cmd_doc.c Unknown Chip ID on boot device
1944 37 common/cmd_doc.c correct chip ID found, device available
1945 -38 common/cmd_doc.c Read Error on boot device
1946 38 common/cmd_doc.c reading Image header from DOC device OK
1947 -39 common/cmd_doc.c Image header has bad magic number
1948 39 common/cmd_doc.c Image header has correct magic number
1949 -40 common/cmd_doc.c Error reading Image from DOC device
1950 40 common/cmd_doc.c Image header has correct magic number
1951 41 common/cmd_ide.c before loading a Image from a IDE device
1952 -42 common/cmd_ide.c Bad usage of "ide" command
1953 42 common/cmd_ide.c correct usage of "ide" command
1954 -43 common/cmd_ide.c No boot device
1955 43 common/cmd_ide.c boot device found
1956 -44 common/cmd_ide.c Device not available
1957 44 common/cmd_ide.c Device available
1958 -45 common/cmd_ide.c wrong partition selected
1959 45 common/cmd_ide.c partition selected
1960 -46 common/cmd_ide.c Unknown partition table
1961 46 common/cmd_ide.c valid partition table found
1962 -47 common/cmd_ide.c Invalid partition type
1963 47 common/cmd_ide.c correct partition type
1964 -48 common/cmd_ide.c Error reading Image Header on boot device
1965 48 common/cmd_ide.c reading Image Header from IDE device OK
1966 -49 common/cmd_ide.c Image header has bad magic number
1967 49 common/cmd_ide.c Image header has correct magic number
1968 -50 common/cmd_ide.c Image header has bad checksum
1969 50 common/cmd_ide.c Image header has correct checksum
1970 -51 common/cmd_ide.c Error reading Image from IDE device
1971 51 common/cmd_ide.c reading Image from IDE device OK
1972 52 common/cmd_nand.c before loading a Image from a NAND device
1973 -53 common/cmd_nand.c Bad usage of "nand" command
1974 53 common/cmd_nand.c correct usage of "nand" command
1975 -54 common/cmd_nand.c No boot device
1976 54 common/cmd_nand.c boot device found
1977 -55 common/cmd_nand.c Unknown Chip ID on boot device
1978 55 common/cmd_nand.c correct chip ID found, device available
1979 -56 common/cmd_nand.c Error reading Image Header on boot device
1980 56 common/cmd_nand.c reading Image Header from NAND device OK
1981 -57 common/cmd_nand.c Image header has bad magic number
1982 57 common/cmd_nand.c Image header has correct magic number
1983 -58 common/cmd_nand.c Error reading Image from NAND device
1984 58 common/cmd_nand.c reading Image from NAND device OK
1986 -60 common/env_common.c Environment has a bad CRC, using default
1988 64 net/eth.c starting with Ethernet configuration.
1989 -64 net/eth.c no Ethernet found.
1990 65 net/eth.c Ethernet found.
1992 -80 common/cmd_net.c usage wrong
1993 80 common/cmd_net.c before calling NetLoop()
1994 -81 common/cmd_net.c some error in NetLoop() occurred
1995 81 common/cmd_net.c NetLoop() back without error
1996 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
1997 82 common/cmd_net.c trying automatic boot
1998 83 common/cmd_net.c running "source" command
1999 -83 common/cmd_net.c some error in automatic boot or "source" command
2000 84 common/cmd_net.c end without errors
2005 100 common/cmd_bootm.c Kernel FIT Image has correct format
2006 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2007 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2008 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2009 102 common/cmd_bootm.c Kernel unit name specified
2010 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2011 103 common/cmd_bootm.c Found configuration node
2012 104 common/cmd_bootm.c Got kernel subimage node offset
2013 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2014 105 common/cmd_bootm.c Kernel subimage hash verification OK
2015 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2016 106 common/cmd_bootm.c Architecture check OK
2017 -106 common/cmd_bootm.c Kernel subimage has wrong type
2018 107 common/cmd_bootm.c Kernel subimage type OK
2019 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2020 108 common/cmd_bootm.c Got kernel subimage data/size
2021 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2022 -109 common/cmd_bootm.c Can't get kernel subimage type
2023 -110 common/cmd_bootm.c Can't get kernel subimage comp
2024 -111 common/cmd_bootm.c Can't get kernel subimage os
2025 -112 common/cmd_bootm.c Can't get kernel subimage load address
2026 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2028 120 common/image.c Start initial ramdisk verification
2029 -120 common/image.c Ramdisk FIT image has incorrect format
2030 121 common/image.c Ramdisk FIT image has correct format
2031 122 common/image.c No ramdisk subimage unit name, using configuration
2032 -122 common/image.c Can't get configuration for ramdisk subimage
2033 123 common/image.c Ramdisk unit name specified
2034 -124 common/image.c Can't get ramdisk subimage node offset
2035 125 common/image.c Got ramdisk subimage node offset
2036 -125 common/image.c Ramdisk subimage hash verification failed
2037 126 common/image.c Ramdisk subimage hash verification OK
2038 -126 common/image.c Ramdisk subimage for unsupported architecture
2039 127 common/image.c Architecture check OK
2040 -127 common/image.c Can't get ramdisk subimage data/size
2041 128 common/image.c Got ramdisk subimage data/size
2042 129 common/image.c Can't get ramdisk load address
2043 -129 common/image.c Got ramdisk load address
2045 -130 common/cmd_doc.c Incorrect FIT image format
2046 131 common/cmd_doc.c FIT image format OK
2048 -140 common/cmd_ide.c Incorrect FIT image format
2049 141 common/cmd_ide.c FIT image format OK
2051 -150 common/cmd_nand.c Incorrect FIT image format
2052 151 common/cmd_nand.c FIT image format OK
2058 [so far only for SMDK2400 and TRAB boards]
2060 - Modem support enable:
2061 CONFIG_MODEM_SUPPORT
2063 - RTS/CTS Flow control enable:
2066 - Modem debug support:
2067 CONFIG_MODEM_SUPPORT_DEBUG
2069 Enables debugging stuff (char screen[1024], dbg())
2070 for modem support. Useful only with BDI2000.
2072 - Interrupt support (PPC):
2074 There are common interrupt_init() and timer_interrupt()
2075 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2076 for CPU specific initialization. interrupt_init_cpu()
2077 should set decrementer_count to appropriate value. If
2078 CPU resets decrementer automatically after interrupt
2079 (ppc4xx) it should set decrementer_count to zero.
2080 timer_interrupt() calls timer_interrupt_cpu() for CPU
2081 specific handling. If board has watchdog / status_led
2082 / other_activity_monitor it works automatically from
2083 general timer_interrupt().
2087 In the target system modem support is enabled when a
2088 specific key (key combination) is pressed during
2089 power-on. Otherwise U-Boot will boot normally
2090 (autoboot). The key_pressed() function is called from
2091 board_init(). Currently key_pressed() is a dummy
2092 function, returning 1 and thus enabling modem
2095 If there are no modem init strings in the
2096 environment, U-Boot proceed to autoboot; the
2097 previous output (banner, info printfs) will be
2100 See also: doc/README.Modem
2103 Configuration Settings:
2104 -----------------------
2106 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2107 undefine this when you're short of memory.
2109 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2110 width of the commands listed in the 'help' command output.
2112 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2113 prompt for user input.
2115 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2117 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2119 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2121 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2122 the application (usually a Linux kernel) when it is
2125 - CONFIG_SYS_BAUDRATE_TABLE:
2126 List of legal baudrate settings for this board.
2128 - CONFIG_SYS_CONSOLE_INFO_QUIET
2129 Suppress display of console information at boot.
2131 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2132 If the board specific function
2133 extern int overwrite_console (void);
2134 returns 1, the stdin, stderr and stdout are switched to the
2135 serial port, else the settings in the environment are used.
2137 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2138 Enable the call to overwrite_console().
2140 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2141 Enable overwrite of previous console environment settings.
2143 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2144 Begin and End addresses of the area used by the
2147 - CONFIG_SYS_ALT_MEMTEST:
2148 Enable an alternate, more extensive memory test.
2150 - CONFIG_SYS_MEMTEST_SCRATCH:
2151 Scratch address used by the alternate memory test
2152 You only need to set this if address zero isn't writeable
2154 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2155 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2156 this specified memory area will get subtracted from the top
2157 (end) of RAM and won't get "touched" at all by U-Boot. By
2158 fixing up gd->ram_size the Linux kernel should gets passed
2159 the now "corrected" memory size and won't touch it either.
2160 This should work for arch/ppc and arch/powerpc. Only Linux
2161 board ports in arch/powerpc with bootwrapper support that
2162 recalculate the memory size from the SDRAM controller setup
2163 will have to get fixed in Linux additionally.
2165 This option can be used as a workaround for the 440EPx/GRx
2166 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2169 WARNING: Please make sure that this value is a multiple of
2170 the Linux page size (normally 4k). If this is not the case,
2171 then the end address of the Linux memory will be located at a
2172 non page size aligned address and this could cause major
2175 - CONFIG_SYS_TFTP_LOADADDR:
2176 Default load address for network file downloads
2178 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2179 Enable temporary baudrate change while serial download
2181 - CONFIG_SYS_SDRAM_BASE:
2182 Physical start address of SDRAM. _Must_ be 0 here.
2184 - CONFIG_SYS_MBIO_BASE:
2185 Physical start address of Motherboard I/O (if using a
2188 - CONFIG_SYS_FLASH_BASE:
2189 Physical start address of Flash memory.
2191 - CONFIG_SYS_MONITOR_BASE:
2192 Physical start address of boot monitor code (set by
2193 make config files to be same as the text base address
2194 (TEXT_BASE) used when linking) - same as
2195 CONFIG_SYS_FLASH_BASE when booting from flash.
2197 - CONFIG_SYS_MONITOR_LEN:
2198 Size of memory reserved for monitor code, used to
2199 determine _at_compile_time_ (!) if the environment is
2200 embedded within the U-Boot image, or in a separate
2203 - CONFIG_SYS_MALLOC_LEN:
2204 Size of DRAM reserved for malloc() use.
2206 - CONFIG_SYS_BOOTM_LEN:
2207 Normally compressed uImages are limited to an
2208 uncompressed size of 8 MBytes. If this is not enough,
2209 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2210 to adjust this setting to your needs.
2212 - CONFIG_SYS_BOOTMAPSZ:
2213 Maximum size of memory mapped by the startup code of
2214 the Linux kernel; all data that must be processed by
2215 the Linux kernel (bd_info, boot arguments, FDT blob if
2216 used) must be put below this limit, unless "bootm_low"
2217 enviroment variable is defined and non-zero. In such case
2218 all data for the Linux kernel must be between "bootm_low"
2219 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ.
2221 - CONFIG_SYS_MAX_FLASH_BANKS:
2222 Max number of Flash memory banks
2224 - CONFIG_SYS_MAX_FLASH_SECT:
2225 Max number of sectors on a Flash chip
2227 - CONFIG_SYS_FLASH_ERASE_TOUT:
2228 Timeout for Flash erase operations (in ms)
2230 - CONFIG_SYS_FLASH_WRITE_TOUT:
2231 Timeout for Flash write operations (in ms)
2233 - CONFIG_SYS_FLASH_LOCK_TOUT
2234 Timeout for Flash set sector lock bit operation (in ms)
2236 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2237 Timeout for Flash clear lock bits operation (in ms)
2239 - CONFIG_SYS_FLASH_PROTECTION
2240 If defined, hardware flash sectors protection is used
2241 instead of U-Boot software protection.
2243 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2245 Enable TFTP transfers directly to flash memory;
2246 without this option such a download has to be
2247 performed in two steps: (1) download to RAM, and (2)
2248 copy from RAM to flash.
2250 The two-step approach is usually more reliable, since
2251 you can check if the download worked before you erase
2252 the flash, but in some situations (when system RAM is
2253 too limited to allow for a temporary copy of the
2254 downloaded image) this option may be very useful.
2256 - CONFIG_SYS_FLASH_CFI:
2257 Define if the flash driver uses extra elements in the
2258 common flash structure for storing flash geometry.
2260 - CONFIG_FLASH_CFI_DRIVER
2261 This option also enables the building of the cfi_flash driver
2262 in the drivers directory
2264 - CONFIG_FLASH_CFI_MTD
2265 This option enables the building of the cfi_mtd driver
2266 in the drivers directory. The driver exports CFI flash
2269 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2270 Use buffered writes to flash.
2272 - CONFIG_FLASH_SPANSION_S29WS_N
2273 s29ws-n MirrorBit flash has non-standard addresses for buffered
2276 - CONFIG_SYS_FLASH_QUIET_TEST
2277 If this option is defined, the common CFI flash doesn't
2278 print it's warning upon not recognized FLASH banks. This
2279 is useful, if some of the configured banks are only
2280 optionally available.
2282 - CONFIG_FLASH_SHOW_PROGRESS
2283 If defined (must be an integer), print out countdown
2284 digits and dots. Recommended value: 45 (9..1) for 80
2285 column displays, 15 (3..1) for 40 column displays.
2287 - CONFIG_SYS_RX_ETH_BUFFER:
2288 Defines the number of Ethernet receive buffers. On some
2289 Ethernet controllers it is recommended to set this value
2290 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2291 buffers can be full shortly after enabling the interface
2292 on high Ethernet traffic.
2293 Defaults to 4 if not defined.
2295 The following definitions that deal with the placement and management
2296 of environment data (variable area); in general, we support the
2297 following configurations:
2299 - CONFIG_ENV_IS_IN_FLASH:
2301 Define this if the environment is in flash memory.
2303 a) The environment occupies one whole flash sector, which is
2304 "embedded" in the text segment with the U-Boot code. This
2305 happens usually with "bottom boot sector" or "top boot
2306 sector" type flash chips, which have several smaller
2307 sectors at the start or the end. For instance, such a
2308 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2309 such a case you would place the environment in one of the
2310 4 kB sectors - with U-Boot code before and after it. With
2311 "top boot sector" type flash chips, you would put the
2312 environment in one of the last sectors, leaving a gap
2313 between U-Boot and the environment.
2315 - CONFIG_ENV_OFFSET:
2317 Offset of environment data (variable area) to the
2318 beginning of flash memory; for instance, with bottom boot
2319 type flash chips the second sector can be used: the offset
2320 for this sector is given here.
2322 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2326 This is just another way to specify the start address of
2327 the flash sector containing the environment (instead of
2330 - CONFIG_ENV_SECT_SIZE:
2332 Size of the sector containing the environment.
2335 b) Sometimes flash chips have few, equal sized, BIG sectors.
2336 In such a case you don't want to spend a whole sector for
2341 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2342 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2343 of this flash sector for the environment. This saves
2344 memory for the RAM copy of the environment.
2346 It may also save flash memory if you decide to use this
2347 when your environment is "embedded" within U-Boot code,
2348 since then the remainder of the flash sector could be used
2349 for U-Boot code. It should be pointed out that this is
2350 STRONGLY DISCOURAGED from a robustness point of view:
2351 updating the environment in flash makes it always
2352 necessary to erase the WHOLE sector. If something goes
2353 wrong before the contents has been restored from a copy in
2354 RAM, your target system will be dead.
2356 - CONFIG_ENV_ADDR_REDUND
2357 CONFIG_ENV_SIZE_REDUND
2359 These settings describe a second storage area used to hold
2360 a redundant copy of the environment data, so that there is
2361 a valid backup copy in case there is a power failure during
2362 a "saveenv" operation.
2364 BE CAREFUL! Any changes to the flash layout, and some changes to the
2365 source code will make it necessary to adapt <board>/u-boot.lds*
2369 - CONFIG_ENV_IS_IN_NVRAM:
2371 Define this if you have some non-volatile memory device
2372 (NVRAM, battery buffered SRAM) which you want to use for the
2378 These two #defines are used to determine the memory area you
2379 want to use for environment. It is assumed that this memory
2380 can just be read and written to, without any special
2383 BE CAREFUL! The first access to the environment happens quite early
2384 in U-Boot initalization (when we try to get the setting of for the
2385 console baudrate). You *MUST* have mapped your NVRAM area then, or
2388 Please note that even with NVRAM we still use a copy of the
2389 environment in RAM: we could work on NVRAM directly, but we want to
2390 keep settings there always unmodified except somebody uses "saveenv"
2391 to save the current settings.
2394 - CONFIG_ENV_IS_IN_EEPROM:
2396 Use this if you have an EEPROM or similar serial access
2397 device and a driver for it.
2399 - CONFIG_ENV_OFFSET:
2402 These two #defines specify the offset and size of the
2403 environment area within the total memory of your EEPROM.
2405 - CONFIG_SYS_I2C_EEPROM_ADDR:
2406 If defined, specified the chip address of the EEPROM device.
2407 The default address is zero.
2409 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2410 If defined, the number of bits used to address bytes in a
2411 single page in the EEPROM device. A 64 byte page, for example
2412 would require six bits.
2414 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2415 If defined, the number of milliseconds to delay between
2416 page writes. The default is zero milliseconds.
2418 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2419 The length in bytes of the EEPROM memory array address. Note
2420 that this is NOT the chip address length!
2422 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2423 EEPROM chips that implement "address overflow" are ones
2424 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2425 address and the extra bits end up in the "chip address" bit
2426 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2429 Note that we consider the length of the address field to
2430 still be one byte because the extra address bits are hidden
2431 in the chip address.
2433 - CONFIG_SYS_EEPROM_SIZE:
2434 The size in bytes of the EEPROM device.
2437 - CONFIG_ENV_IS_IN_DATAFLASH:
2439 Define this if you have a DataFlash memory device which you
2440 want to use for the environment.
2442 - CONFIG_ENV_OFFSET:
2446 These three #defines specify the offset and size of the
2447 environment area within the total memory of your DataFlash placed
2448 at the specified address.
2450 - CONFIG_ENV_IS_IN_NAND:
2452 Define this if you have a NAND device which you want to use
2453 for the environment.
2455 - CONFIG_ENV_OFFSET:
2458 These two #defines specify the offset and size of the environment
2459 area within the first NAND device.
2461 - CONFIG_ENV_OFFSET_REDUND
2463 This setting describes a second storage area of CONFIG_ENV_SIZE
2464 size used to hold a redundant copy of the environment data,
2465 so that there is a valid backup copy in case there is a
2466 power failure during a "saveenv" operation.
2468 Note: CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND must be aligned
2469 to a block boundary, and CONFIG_ENV_SIZE must be a multiple of
2470 the NAND devices block size.
2472 - CONFIG_NAND_ENV_DST
2474 Defines address in RAM to which the nand_spl code should copy the
2475 environment. If redundant environment is used, it will be copied to
2476 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2478 - CONFIG_SYS_SPI_INIT_OFFSET
2480 Defines offset to the initial SPI buffer area in DPRAM. The
2481 area is used at an early stage (ROM part) if the environment
2482 is configured to reside in the SPI EEPROM: We need a 520 byte
2483 scratch DPRAM area. It is used between the two initialization
2484 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2485 to be a good choice since it makes it far enough from the
2486 start of the data area as well as from the stack pointer.
2488 Please note that the environment is read-only until the monitor
2489 has been relocated to RAM and a RAM copy of the environment has been
2490 created; also, when using EEPROM you will have to use getenv_r()
2491 until then to read environment variables.
2493 The environment is protected by a CRC32 checksum. Before the monitor
2494 is relocated into RAM, as a result of a bad CRC you will be working
2495 with the compiled-in default environment - *silently*!!! [This is
2496 necessary, because the first environment variable we need is the
2497 "baudrate" setting for the console - if we have a bad CRC, we don't
2498 have any device yet where we could complain.]
2500 Note: once the monitor has been relocated, then it will complain if
2501 the default environment is used; a new CRC is computed as soon as you
2502 use the "saveenv" command to store a valid environment.
2504 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2505 Echo the inverted Ethernet link state to the fault LED.
2507 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2508 also needs to be defined.
2510 - CONFIG_SYS_FAULT_MII_ADDR:
2511 MII address of the PHY to check for the Ethernet link state.
2513 - CONFIG_SYS_64BIT_VSPRINTF:
2514 Makes vsprintf (and all *printf functions) support printing
2515 of 64bit values by using the L quantifier
2517 - CONFIG_SYS_64BIT_STRTOUL:
2518 Adds simple_strtoull that returns a 64bit value
2520 - CONFIG_NS16550_MIN_FUNCTIONS:
2521 Define this if you desire to only have use of the NS16550_init
2522 and NS16550_putc functions for the serial driver located at
2523 drivers/serial/ns16550.c. This option is useful for saving
2524 space for already greatly restricted images, including but not
2525 limited to NAND_SPL configurations.
2527 Low Level (hardware related) configuration options:
2528 ---------------------------------------------------
2530 - CONFIG_SYS_CACHELINE_SIZE:
2531 Cache Line Size of the CPU.
2533 - CONFIG_SYS_DEFAULT_IMMR:
2534 Default address of the IMMR after system reset.
2536 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2537 and RPXsuper) to be able to adjust the position of
2538 the IMMR register after a reset.
2540 - Floppy Disk Support:
2541 CONFIG_SYS_FDC_DRIVE_NUMBER
2543 the default drive number (default value 0)
2545 CONFIG_SYS_ISA_IO_STRIDE
2547 defines the spacing between FDC chipset registers
2550 CONFIG_SYS_ISA_IO_OFFSET
2552 defines the offset of register from address. It
2553 depends on which part of the data bus is connected to
2554 the FDC chipset. (default value 0)
2556 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2557 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2560 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2561 fdc_hw_init() is called at the beginning of the FDC
2562 setup. fdc_hw_init() must be provided by the board
2563 source code. It is used to make hardware dependant
2566 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2567 DO NOT CHANGE unless you know exactly what you're
2568 doing! (11-4) [MPC8xx/82xx systems only]
2570 - CONFIG_SYS_INIT_RAM_ADDR:
2572 Start address of memory area that can be used for
2573 initial data and stack; please note that this must be
2574 writable memory that is working WITHOUT special
2575 initialization, i. e. you CANNOT use normal RAM which
2576 will become available only after programming the
2577 memory controller and running certain initialization
2580 U-Boot uses the following memory types:
2581 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2582 - MPC824X: data cache
2583 - PPC4xx: data cache
2585 - CONFIG_SYS_GBL_DATA_OFFSET:
2587 Offset of the initial data structure in the memory
2588 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2589 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2590 data is located at the end of the available space
2591 (sometimes written as (CONFIG_SYS_INIT_RAM_END -
2592 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2593 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2594 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2597 On the MPC824X (or other systems that use the data
2598 cache for initial memory) the address chosen for
2599 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2600 point to an otherwise UNUSED address space between
2601 the top of RAM and the start of the PCI space.
2603 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2605 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2607 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2609 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2611 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2613 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2615 - CONFIG_SYS_OR_TIMING_SDRAM:
2618 - CONFIG_SYS_MAMR_PTA:
2619 periodic timer for refresh
2621 - CONFIG_SYS_DER: Debug Event Register (37-47)
2623 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2624 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2625 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2626 CONFIG_SYS_BR1_PRELIM:
2627 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2629 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2630 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2631 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2632 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2634 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2635 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2636 Machine Mode Register and Memory Periodic Timer
2637 Prescaler definitions (SDRAM timing)
2639 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2640 enable I2C microcode relocation patch (MPC8xx);
2641 define relocation offset in DPRAM [DSP2]
2643 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2644 enable SMC microcode relocation patch (MPC8xx);
2645 define relocation offset in DPRAM [SMC1]
2647 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2648 enable SPI microcode relocation patch (MPC8xx);
2649 define relocation offset in DPRAM [SCC4]
2651 - CONFIG_SYS_USE_OSCCLK:
2652 Use OSCM clock mode on MBX8xx board. Be careful,
2653 wrong setting might damage your board. Read
2654 doc/README.MBX before setting this variable!
2656 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2657 Offset of the bootmode word in DPRAM used by post
2658 (Power On Self Tests). This definition overrides
2659 #define'd default value in commproc.h resp.
2662 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2663 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2664 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2665 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2666 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2667 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2668 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2669 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2670 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2672 - CONFIG_PCI_DISABLE_PCIE:
2673 Disable PCI-Express on systems where it is supported but not
2677 Get DDR timing information from an I2C EEPROM. Common
2678 with pluggable memory modules such as SODIMMs
2681 I2C address of the SPD EEPROM
2683 - CONFIG_SYS_SPD_BUS_NUM
2684 If SPD EEPROM is on an I2C bus other than the first
2685 one, specify here. Note that the value must resolve
2686 to something your driver can deal with.
2688 - CONFIG_SYS_83XX_DDR_USES_CS0
2689 Only for 83xx systems. If specified, then DDR should
2690 be configured using CS0 and CS1 instead of CS2 and CS3.
2692 - CONFIG_ETHER_ON_FEC[12]
2693 Define to enable FEC[12] on a 8xx series processor.
2695 - CONFIG_FEC[12]_PHY
2696 Define to the hardcoded PHY address which corresponds
2697 to the given FEC; i. e.
2698 #define CONFIG_FEC1_PHY 4
2699 means that the PHY with address 4 is connected to FEC1
2701 When set to -1, means to probe for first available.
2703 - CONFIG_FEC[12]_PHY_NORXERR
2704 The PHY does not have a RXERR line (RMII only).
2705 (so program the FEC to ignore it).
2708 Enable RMII mode for all FECs.
2709 Note that this is a global option, we can't
2710 have one FEC in standard MII mode and another in RMII mode.
2712 - CONFIG_CRC32_VERIFY
2713 Add a verify option to the crc32 command.
2716 => crc32 -v <address> <count> <crc32>
2718 Where address/count indicate a memory area
2719 and crc32 is the correct crc32 which the
2723 Add the "loopw" memory command. This only takes effect if
2724 the memory commands are activated globally (CONFIG_CMD_MEM).
2727 Add the "mdc" and "mwc" memory commands. These are cyclic
2732 This command will print 4 bytes (10,11,12,13) each 500 ms.
2734 => mwc.l 100 12345678 10
2735 This command will write 12345678 to address 100 all 10 ms.
2737 This only takes effect if the memory commands are activated
2738 globally (CONFIG_CMD_MEM).
2740 - CONFIG_SKIP_LOWLEVEL_INIT
2741 - CONFIG_SKIP_RELOCATE_UBOOT
2743 [ARM only] If these variables are defined, then
2744 certain low level initializations (like setting up
2745 the memory controller) are omitted and/or U-Boot does
2746 not relocate itself into RAM.
2747 Normally these variables MUST NOT be defined. The
2748 only exception is when U-Boot is loaded (to RAM) by
2749 some other boot loader or by a debugger which
2750 performs these initializations itself.
2754 Modifies the behaviour of start.S when compiling a loader
2755 that is executed before the actual U-Boot. E.g. when
2756 compiling a NAND SPL.
2758 Building the Software:
2759 ======================
2761 Building U-Boot has been tested in several native build environments
2762 and in many different cross environments. Of course we cannot support
2763 all possibly existing versions of cross development tools in all
2764 (potentially obsolete) versions. In case of tool chain problems we
2765 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
2766 which is extensively used to build and test U-Boot.
2768 If you are not using a native environment, it is assumed that you
2769 have GNU cross compiling tools available in your path. In this case,
2770 you must set the environment variable CROSS_COMPILE in your shell.
2771 Note that no changes to the Makefile or any other source files are
2772 necessary. For example using the ELDK on a 4xx CPU, please enter:
2774 $ CROSS_COMPILE=ppc_4xx-
2775 $ export CROSS_COMPILE
2777 Note: If you wish to generate Windows versions of the utilities in
2778 the tools directory you can use the MinGW toolchain
2779 (http://www.mingw.org). Set your HOST tools to the MinGW
2780 toolchain and execute 'make tools'. For example:
2782 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
2784 Binaries such as tools/mkimage.exe will be created which can
2785 be executed on computers running Windows.
2787 U-Boot is intended to be simple to build. After installing the
2788 sources you must configure U-Boot for one specific board type. This
2793 where "NAME_config" is the name of one of the existing configu-
2794 rations; see the main Makefile for supported names.
2796 Note: for some board special configuration names may exist; check if
2797 additional information is available from the board vendor; for
2798 instance, the TQM823L systems are available without (standard)
2799 or with LCD support. You can select such additional "features"
2800 when choosing the configuration, i. e.
2803 - will configure for a plain TQM823L, i. e. no LCD support
2805 make TQM823L_LCD_config
2806 - will configure for a TQM823L with U-Boot console on LCD
2811 Finally, type "make all", and you should get some working U-Boot
2812 images ready for download to / installation on your system:
2814 - "u-boot.bin" is a raw binary image
2815 - "u-boot" is an image in ELF binary format
2816 - "u-boot.srec" is in Motorola S-Record format
2818 By default the build is performed locally and the objects are saved
2819 in the source directory. One of the two methods can be used to change
2820 this behavior and build U-Boot to some external directory:
2822 1. Add O= to the make command line invocations:
2824 make O=/tmp/build distclean
2825 make O=/tmp/build NAME_config
2826 make O=/tmp/build all
2828 2. Set environment variable BUILD_DIR to point to the desired location:
2830 export BUILD_DIR=/tmp/build
2835 Note that the command line "O=" setting overrides the BUILD_DIR environment
2839 Please be aware that the Makefiles assume you are using GNU make, so
2840 for instance on NetBSD you might need to use "gmake" instead of
2844 If the system board that you have is not listed, then you will need
2845 to port U-Boot to your hardware platform. To do this, follow these
2848 1. Add a new configuration option for your board to the toplevel
2849 "Makefile" and to the "MAKEALL" script, using the existing
2850 entries as examples. Note that here and at many other places
2851 boards and other names are listed in alphabetical sort order. Please
2853 2. Create a new directory to hold your board specific code. Add any
2854 files you need. In your board directory, you will need at least
2855 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2856 3. Create a new configuration file "include/configs/<board>.h" for
2858 3. If you're porting U-Boot to a new CPU, then also create a new
2859 directory to hold your CPU specific code. Add any files you need.
2860 4. Run "make <board>_config" with your new name.
2861 5. Type "make", and you should get a working "u-boot.srec" file
2862 to be installed on your target system.
2863 6. Debug and solve any problems that might arise.
2864 [Of course, this last step is much harder than it sounds.]
2867 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2868 ==============================================================
2870 If you have modified U-Boot sources (for instance added a new board
2871 or support for new devices, a new CPU, etc.) you are expected to
2872 provide feedback to the other developers. The feedback normally takes
2873 the form of a "patch", i. e. a context diff against a certain (latest
2874 official or latest in the git repository) version of U-Boot sources.
2876 But before you submit such a patch, please verify that your modifi-
2877 cation did not break existing code. At least make sure that *ALL* of
2878 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2879 just run the "MAKEALL" script, which will configure and build U-Boot
2880 for ALL supported system. Be warned, this will take a while. You can
2881 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2882 environment variable to the script, i. e. to use the ELDK cross tools
2885 CROSS_COMPILE=ppc_8xx- MAKEALL
2887 or to build on a native PowerPC system you can type
2889 CROSS_COMPILE=' ' MAKEALL
2891 When using the MAKEALL script, the default behaviour is to build
2892 U-Boot in the source directory. This location can be changed by
2893 setting the BUILD_DIR environment variable. Also, for each target
2894 built, the MAKEALL script saves two log files (<target>.ERR and
2895 <target>.MAKEALL) in the <source dir>/LOG directory. This default
2896 location can be changed by setting the MAKEALL_LOGDIR environment
2897 variable. For example:
2899 export BUILD_DIR=/tmp/build
2900 export MAKEALL_LOGDIR=/tmp/log
2901 CROSS_COMPILE=ppc_8xx- MAKEALL
2903 With the above settings build objects are saved in the /tmp/build,
2904 log files are saved in the /tmp/log and the source tree remains clean
2905 during the whole build process.
2908 See also "U-Boot Porting Guide" below.
2911 Monitor Commands - Overview:
2912 ============================
2914 go - start application at address 'addr'
2915 run - run commands in an environment variable
2916 bootm - boot application image from memory
2917 bootp - boot image via network using BootP/TFTP protocol
2918 tftpboot- boot image via network using TFTP protocol
2919 and env variables "ipaddr" and "serverip"
2920 (and eventually "gatewayip")
2921 rarpboot- boot image via network using RARP/TFTP protocol
2922 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2923 loads - load S-Record file over serial line
2924 loadb - load binary file over serial line (kermit mode)
2926 mm - memory modify (auto-incrementing)
2927 nm - memory modify (constant address)
2928 mw - memory write (fill)
2930 cmp - memory compare
2931 crc32 - checksum calculation
2932 i2c - I2C sub-system
2933 sspi - SPI utility commands
2934 base - print or set address offset
2935 printenv- print environment variables
2936 setenv - set environment variables
2937 saveenv - save environment variables to persistent storage
2938 protect - enable or disable FLASH write protection
2939 erase - erase FLASH memory
2940 flinfo - print FLASH memory information
2941 bdinfo - print Board Info structure
2942 iminfo - print header information for application image
2943 coninfo - print console devices and informations
2944 ide - IDE sub-system
2945 loop - infinite loop on address range
2946 loopw - infinite write loop on address range
2947 mtest - simple RAM test
2948 icache - enable or disable instruction cache
2949 dcache - enable or disable data cache
2950 reset - Perform RESET of the CPU
2951 echo - echo args to console
2952 version - print monitor version
2953 help - print online help
2954 ? - alias for 'help'
2957 Monitor Commands - Detailed Description:
2958 ========================================
2962 For now: just type "help <command>".
2965 Environment Variables:
2966 ======================
2968 U-Boot supports user configuration using Environment Variables which
2969 can be made persistent by saving to Flash memory.
2971 Environment Variables are set using "setenv", printed using
2972 "printenv", and saved to Flash using "saveenv". Using "setenv"
2973 without a value can be used to delete a variable from the
2974 environment. As long as you don't save the environment you are
2975 working with an in-memory copy. In case the Flash area containing the
2976 environment is erased by accident, a default environment is provided.
2978 Some configuration options can be set using Environment Variables:
2980 baudrate - see CONFIG_BAUDRATE
2982 bootdelay - see CONFIG_BOOTDELAY
2984 bootcmd - see CONFIG_BOOTCOMMAND
2986 bootargs - Boot arguments when booting an RTOS image
2988 bootfile - Name of the image to load with TFTP
2990 bootm_low - Memory range available for image processing in the bootm
2991 command can be restricted. This variable is given as
2992 a hexadecimal number and defines lowest address allowed
2993 for use by the bootm command. See also "bootm_size"
2994 environment variable. Address defined by "bootm_low" is
2995 also the base of the initial memory mapping for the Linux
2996 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ.
2998 bootm_size - Memory range available for image processing in the bootm
2999 command can be restricted. This variable is given as
3000 a hexadecimal number and defines the size of the region
3001 allowed for use by the bootm command. See also "bootm_low"
3002 environment variable.
3004 updatefile - Location of the software update file on a TFTP server, used
3005 by the automatic software update feature. Please refer to
3006 documentation in doc/README.update for more details.
3008 autoload - if set to "no" (any string beginning with 'n'),
3009 "bootp" will just load perform a lookup of the
3010 configuration from the BOOTP server, but not try to
3011 load any image using TFTP
3013 autostart - if set to "yes", an image loaded using the "bootp",
3014 "rarpboot", "tftpboot" or "diskboot" commands will
3015 be automatically started (by internally calling
3018 If set to "no", a standalone image passed to the
3019 "bootm" command will be copied to the load address
3020 (and eventually uncompressed), but NOT be started.
3021 This can be used to load and uncompress arbitrary
3024 i2cfast - (PPC405GP|PPC405EP only)
3025 if set to 'y' configures Linux I2C driver for fast
3026 mode (400kHZ). This environment variable is used in
3027 initialization code. So, for changes to be effective
3028 it must be saved and board must be reset.
3030 initrd_high - restrict positioning of initrd images:
3031 If this variable is not set, initrd images will be
3032 copied to the highest possible address in RAM; this
3033 is usually what you want since it allows for
3034 maximum initrd size. If for some reason you want to
3035 make sure that the initrd image is loaded below the
3036 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3037 variable to a value of "no" or "off" or "0".
3038 Alternatively, you can set it to a maximum upper
3039 address to use (U-Boot will still check that it
3040 does not overwrite the U-Boot stack and data).
3042 For instance, when you have a system with 16 MB
3043 RAM, and want to reserve 4 MB from use by Linux,
3044 you can do this by adding "mem=12M" to the value of
3045 the "bootargs" variable. However, now you must make
3046 sure that the initrd image is placed in the first
3047 12 MB as well - this can be done with
3049 setenv initrd_high 00c00000
3051 If you set initrd_high to 0xFFFFFFFF, this is an
3052 indication to U-Boot that all addresses are legal
3053 for the Linux kernel, including addresses in flash
3054 memory. In this case U-Boot will NOT COPY the
3055 ramdisk at all. This may be useful to reduce the
3056 boot time on your system, but requires that this
3057 feature is supported by your Linux kernel.
3059 ipaddr - IP address; needed for tftpboot command
3061 loadaddr - Default load address for commands like "bootp",
3062 "rarpboot", "tftpboot", "loadb" or "diskboot"
3064 loads_echo - see CONFIG_LOADS_ECHO
3066 serverip - TFTP server IP address; needed for tftpboot command
3068 bootretry - see CONFIG_BOOT_RETRY_TIME
3070 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3072 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3074 ethprime - When CONFIG_NET_MULTI is enabled controls which
3075 interface is used first.
3077 ethact - When CONFIG_NET_MULTI is enabled controls which
3078 interface is currently active. For example you
3079 can do the following
3081 => setenv ethact FEC ETHERNET
3082 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
3083 => setenv ethact SCC ETHERNET
3084 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
3086 ethrotate - When set to "no" U-Boot does not go through all
3087 available network interfaces.
3088 It just stays at the currently selected interface.
3090 netretry - When set to "no" each network operation will
3091 either succeed or fail without retrying.
3092 When set to "once" the network operation will
3093 fail when all the available network interfaces
3094 are tried once without success.
3095 Useful on scripts which control the retry operation
3098 npe_ucode - set load address for the NPE microcode
3100 tftpsrcport - If this is set, the value is used for TFTP's
3103 tftpdstport - If this is set, the value is used for TFTP's UDP
3104 destination port instead of the Well Know Port 69.
3106 vlan - When set to a value < 4095 the traffic over
3107 Ethernet is encapsulated/received over 802.1q
3110 The following environment variables may be used and automatically
3111 updated by the network boot commands ("bootp" and "rarpboot"),
3112 depending the information provided by your boot server:
3114 bootfile - see above
3115 dnsip - IP address of your Domain Name Server
3116 dnsip2 - IP address of your secondary Domain Name Server
3117 gatewayip - IP address of the Gateway (Router) to use
3118 hostname - Target hostname
3120 netmask - Subnet Mask
3121 rootpath - Pathname of the root filesystem on the NFS server
3122 serverip - see above
3125 There are two special Environment Variables:
3127 serial# - contains hardware identification information such
3128 as type string and/or serial number
3129 ethaddr - Ethernet address
3131 These variables can be set only once (usually during manufacturing of
3132 the board). U-Boot refuses to delete or overwrite these variables
3133 once they have been set once.
3136 Further special Environment Variables:
3138 ver - Contains the U-Boot version string as printed
3139 with the "version" command. This variable is
3140 readonly (see CONFIG_VERSION_VARIABLE).
3143 Please note that changes to some configuration parameters may take
3144 only effect after the next boot (yes, that's just like Windoze :-).
3147 Command Line Parsing:
3148 =====================
3150 There are two different command line parsers available with U-Boot:
3151 the old "simple" one, and the much more powerful "hush" shell:
3153 Old, simple command line parser:
3154 --------------------------------
3156 - supports environment variables (through setenv / saveenv commands)
3157 - several commands on one line, separated by ';'
3158 - variable substitution using "... ${name} ..." syntax
3159 - special characters ('$', ';') can be escaped by prefixing with '\',
3161 setenv bootcmd bootm \${address}
3162 - You can also escape text by enclosing in single apostrophes, for example:
3163 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3168 - similar to Bourne shell, with control structures like
3169 if...then...else...fi, for...do...done; while...do...done,
3170 until...do...done, ...
3171 - supports environment ("global") variables (through setenv / saveenv
3172 commands) and local shell variables (through standard shell syntax
3173 "name=value"); only environment variables can be used with "run"
3179 (1) If a command line (or an environment variable executed by a "run"
3180 command) contains several commands separated by semicolon, and
3181 one of these commands fails, then the remaining commands will be
3184 (2) If you execute several variables with one call to run (i. e.
3185 calling run with a list of variables as arguments), any failing
3186 command will cause "run" to terminate, i. e. the remaining
3187 variables are not executed.
3189 Note for Redundant Ethernet Interfaces:
3190 =======================================
3192 Some boards come with redundant Ethernet interfaces; U-Boot supports
3193 such configurations and is capable of automatic selection of a
3194 "working" interface when needed. MAC assignment works as follows:
3196 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3197 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3198 "eth1addr" (=>eth1), "eth2addr", ...
3200 If the network interface stores some valid MAC address (for instance
3201 in SROM), this is used as default address if there is NO correspon-
3202 ding setting in the environment; if the corresponding environment
3203 variable is set, this overrides the settings in the card; that means:
3205 o If the SROM has a valid MAC address, and there is no address in the
3206 environment, the SROM's address is used.
3208 o If there is no valid address in the SROM, and a definition in the
3209 environment exists, then the value from the environment variable is
3212 o If both the SROM and the environment contain a MAC address, and
3213 both addresses are the same, this MAC address is used.
3215 o If both the SROM and the environment contain a MAC address, and the
3216 addresses differ, the value from the environment is used and a
3219 o If neither SROM nor the environment contain a MAC address, an error
3226 U-Boot is capable of booting (and performing other auxiliary operations on)
3227 images in two formats:
3229 New uImage format (FIT)
3230 -----------------------
3232 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3233 to Flattened Device Tree). It allows the use of images with multiple
3234 components (several kernels, ramdisks, etc.), with contents protected by
3235 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3241 Old image format is based on binary files which can be basically anything,
3242 preceded by a special header; see the definitions in include/image.h for
3243 details; basically, the header defines the following image properties:
3245 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3246 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3247 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3248 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3250 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3251 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3252 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
3253 * Compression Type (uncompressed, gzip, bzip2)
3259 The header is marked by a special Magic Number, and both the header
3260 and the data portions of the image are secured against corruption by
3267 Although U-Boot should support any OS or standalone application
3268 easily, the main focus has always been on Linux during the design of
3271 U-Boot includes many features that so far have been part of some
3272 special "boot loader" code within the Linux kernel. Also, any
3273 "initrd" images to be used are no longer part of one big Linux image;
3274 instead, kernel and "initrd" are separate images. This implementation
3275 serves several purposes:
3277 - the same features can be used for other OS or standalone
3278 applications (for instance: using compressed images to reduce the
3279 Flash memory footprint)
3281 - it becomes much easier to port new Linux kernel versions because
3282 lots of low-level, hardware dependent stuff are done by U-Boot
3284 - the same Linux kernel image can now be used with different "initrd"
3285 images; of course this also means that different kernel images can
3286 be run with the same "initrd". This makes testing easier (you don't
3287 have to build a new "zImage.initrd" Linux image when you just
3288 change a file in your "initrd"). Also, a field-upgrade of the
3289 software is easier now.
3295 Porting Linux to U-Boot based systems:
3296 ---------------------------------------
3298 U-Boot cannot save you from doing all the necessary modifications to
3299 configure the Linux device drivers for use with your target hardware
3300 (no, we don't intend to provide a full virtual machine interface to
3303 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
3305 Just make sure your machine specific header file (for instance
3306 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3307 Information structure as we define in include/asm-<arch>/u-boot.h,
3308 and make sure that your definition of IMAP_ADDR uses the same value
3309 as your U-Boot configuration in CONFIG_SYS_IMMR.
3312 Configuring the Linux kernel:
3313 -----------------------------
3315 No specific requirements for U-Boot. Make sure you have some root
3316 device (initial ramdisk, NFS) for your target system.
3319 Building a Linux Image:
3320 -----------------------
3322 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3323 not used. If you use recent kernel source, a new build target
3324 "uImage" will exist which automatically builds an image usable by
3325 U-Boot. Most older kernels also have support for a "pImage" target,
3326 which was introduced for our predecessor project PPCBoot and uses a
3327 100% compatible format.
3336 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3337 encapsulate a compressed Linux kernel image with header information,
3338 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3340 * build a standard "vmlinux" kernel image (in ELF binary format):
3342 * convert the kernel into a raw binary image:
3344 ${CROSS_COMPILE}-objcopy -O binary \
3345 -R .note -R .comment \
3346 -S vmlinux linux.bin
3348 * compress the binary image:
3352 * package compressed binary image for U-Boot:
3354 mkimage -A ppc -O linux -T kernel -C gzip \
3355 -a 0 -e 0 -n "Linux Kernel Image" \
3356 -d linux.bin.gz uImage
3359 The "mkimage" tool can also be used to create ramdisk images for use
3360 with U-Boot, either separated from the Linux kernel image, or
3361 combined into one file. "mkimage" encapsulates the images with a 64
3362 byte header containing information about target architecture,
3363 operating system, image type, compression method, entry points, time
3364 stamp, CRC32 checksums, etc.
3366 "mkimage" can be called in two ways: to verify existing images and
3367 print the header information, or to build new images.
3369 In the first form (with "-l" option) mkimage lists the information
3370 contained in the header of an existing U-Boot image; this includes
3371 checksum verification:
3373 tools/mkimage -l image
3374 -l ==> list image header information
3376 The second form (with "-d" option) is used to build a U-Boot image
3377 from a "data file" which is used as image payload:
3379 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3380 -n name -d data_file image
3381 -A ==> set architecture to 'arch'
3382 -O ==> set operating system to 'os'
3383 -T ==> set image type to 'type'
3384 -C ==> set compression type 'comp'
3385 -a ==> set load address to 'addr' (hex)
3386 -e ==> set entry point to 'ep' (hex)
3387 -n ==> set image name to 'name'
3388 -d ==> use image data from 'datafile'
3390 Right now, all Linux kernels for PowerPC systems use the same load
3391 address (0x00000000), but the entry point address depends on the
3394 - 2.2.x kernels have the entry point at 0x0000000C,
3395 - 2.3.x and later kernels have the entry point at 0x00000000.
3397 So a typical call to build a U-Boot image would read:
3399 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3400 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3401 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
3402 > examples/uImage.TQM850L
3403 Image Name: 2.4.4 kernel for TQM850L
3404 Created: Wed Jul 19 02:34:59 2000
3405 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3406 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3407 Load Address: 0x00000000
3408 Entry Point: 0x00000000
3410 To verify the contents of the image (or check for corruption):
3412 -> tools/mkimage -l examples/uImage.TQM850L
3413 Image Name: 2.4.4 kernel for TQM850L
3414 Created: Wed Jul 19 02:34:59 2000
3415 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3416 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3417 Load Address: 0x00000000
3418 Entry Point: 0x00000000
3420 NOTE: for embedded systems where boot time is critical you can trade
3421 speed for memory and install an UNCOMPRESSED image instead: this
3422 needs more space in Flash, but boots much faster since it does not
3423 need to be uncompressed:
3425 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
3426 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3427 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3428 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
3429 > examples/uImage.TQM850L-uncompressed
3430 Image Name: 2.4.4 kernel for TQM850L
3431 Created: Wed Jul 19 02:34:59 2000
3432 Image Type: PowerPC Linux Kernel Image (uncompressed)
3433 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3434 Load Address: 0x00000000
3435 Entry Point: 0x00000000
3438 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3439 when your kernel is intended to use an initial ramdisk:
3441 -> tools/mkimage -n 'Simple Ramdisk Image' \
3442 > -A ppc -O linux -T ramdisk -C gzip \
3443 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3444 Image Name: Simple Ramdisk Image
3445 Created: Wed Jan 12 14:01:50 2000
3446 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3447 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3448 Load Address: 0x00000000
3449 Entry Point: 0x00000000
3452 Installing a Linux Image:
3453 -------------------------
3455 To downloading a U-Boot image over the serial (console) interface,
3456 you must convert the image to S-Record format:
3458 objcopy -I binary -O srec examples/image examples/image.srec
3460 The 'objcopy' does not understand the information in the U-Boot
3461 image header, so the resulting S-Record file will be relative to
3462 address 0x00000000. To load it to a given address, you need to
3463 specify the target address as 'offset' parameter with the 'loads'
3466 Example: install the image to address 0x40100000 (which on the
3467 TQM8xxL is in the first Flash bank):
3469 => erase 40100000 401FFFFF
3475 ## Ready for S-Record download ...
3476 ~>examples/image.srec
3477 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3479 15989 15990 15991 15992
3480 [file transfer complete]
3482 ## Start Addr = 0x00000000
3485 You can check the success of the download using the 'iminfo' command;
3486 this includes a checksum verification so you can be sure no data
3487 corruption happened:
3491 ## Checking Image at 40100000 ...
3492 Image Name: 2.2.13 for initrd on TQM850L
3493 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3494 Data Size: 335725 Bytes = 327 kB = 0 MB
3495 Load Address: 00000000
3496 Entry Point: 0000000c
3497 Verifying Checksum ... OK
3503 The "bootm" command is used to boot an application that is stored in
3504 memory (RAM or Flash). In case of a Linux kernel image, the contents
3505 of the "bootargs" environment variable is passed to the kernel as
3506 parameters. You can check and modify this variable using the
3507 "printenv" and "setenv" commands:
3510 => printenv bootargs
3511 bootargs=root=/dev/ram
3513 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3515 => printenv bootargs
3516 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3519 ## Booting Linux kernel at 40020000 ...
3520 Image Name: 2.2.13 for NFS on TQM850L
3521 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3522 Data Size: 381681 Bytes = 372 kB = 0 MB
3523 Load Address: 00000000
3524 Entry Point: 0000000c
3525 Verifying Checksum ... OK
3526 Uncompressing Kernel Image ... OK
3527 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
3528 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3529 time_init: decrementer frequency = 187500000/60
3530 Calibrating delay loop... 49.77 BogoMIPS
3531 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3534 If you want to boot a Linux kernel with initial RAM disk, you pass
3535 the memory addresses of both the kernel and the initrd image (PPBCOOT
3536 format!) to the "bootm" command:
3538 => imi 40100000 40200000
3540 ## Checking Image at 40100000 ...
3541 Image Name: 2.2.13 for initrd on TQM850L
3542 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3543 Data Size: 335725 Bytes = 327 kB = 0 MB
3544 Load Address: 00000000
3545 Entry Point: 0000000c
3546 Verifying Checksum ... OK
3548 ## Checking Image at 40200000 ...
3549 Image Name: Simple Ramdisk Image
3550 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3551 Data Size: 566530 Bytes = 553 kB = 0 MB
3552 Load Address: 00000000
3553 Entry Point: 00000000
3554 Verifying Checksum ... OK
3556 => bootm 40100000 40200000
3557 ## Booting Linux kernel at 40100000 ...
3558 Image Name: 2.2.13 for initrd on TQM850L
3559 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3560 Data Size: 335725 Bytes = 327 kB = 0 MB
3561 Load Address: 00000000
3562 Entry Point: 0000000c
3563 Verifying Checksum ... OK
3564 Uncompressing Kernel Image ... OK
3565 ## Loading RAMDisk Image at 40200000 ...
3566 Image Name: Simple Ramdisk Image
3567 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3568 Data Size: 566530 Bytes = 553 kB = 0 MB
3569 Load Address: 00000000
3570 Entry Point: 00000000
3571 Verifying Checksum ... OK
3572 Loading Ramdisk ... OK
3573 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
3574 Boot arguments: root=/dev/ram
3575 time_init: decrementer frequency = 187500000/60
3576 Calibrating delay loop... 49.77 BogoMIPS
3578 RAMDISK: Compressed image found at block 0
3579 VFS: Mounted root (ext2 filesystem).
3583 Boot Linux and pass a flat device tree:
3586 First, U-Boot must be compiled with the appropriate defines. See the section
3587 titled "Linux Kernel Interface" above for a more in depth explanation. The
3588 following is an example of how to start a kernel and pass an updated
3594 oft=oftrees/mpc8540ads.dtb
3595 => tftp $oftaddr $oft
3596 Speed: 1000, full duplex
3598 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3599 Filename 'oftrees/mpc8540ads.dtb'.
3600 Load address: 0x300000
3603 Bytes transferred = 4106 (100a hex)
3604 => tftp $loadaddr $bootfile
3605 Speed: 1000, full duplex
3607 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3609 Load address: 0x200000
3610 Loading:############
3612 Bytes transferred = 1029407 (fb51f hex)
3617 => bootm $loadaddr - $oftaddr
3618 ## Booting image at 00200000 ...
3619 Image Name: Linux-2.6.17-dirty
3620 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3621 Data Size: 1029343 Bytes = 1005.2 kB
3622 Load Address: 00000000
3623 Entry Point: 00000000
3624 Verifying Checksum ... OK
3625 Uncompressing Kernel Image ... OK
3626 Booting using flat device tree at 0x300000
3627 Using MPC85xx ADS machine description
3628 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3632 More About U-Boot Image Types:
3633 ------------------------------
3635 U-Boot supports the following image types:
3637 "Standalone Programs" are directly runnable in the environment
3638 provided by U-Boot; it is expected that (if they behave
3639 well) you can continue to work in U-Boot after return from
3640 the Standalone Program.
3641 "OS Kernel Images" are usually images of some Embedded OS which
3642 will take over control completely. Usually these programs
3643 will install their own set of exception handlers, device
3644 drivers, set up the MMU, etc. - this means, that you cannot
3645 expect to re-enter U-Boot except by resetting the CPU.
3646 "RAMDisk Images" are more or less just data blocks, and their
3647 parameters (address, size) are passed to an OS kernel that is
3649 "Multi-File Images" contain several images, typically an OS
3650 (Linux) kernel image and one or more data images like
3651 RAMDisks. This construct is useful for instance when you want
3652 to boot over the network using BOOTP etc., where the boot
3653 server provides just a single image file, but you want to get
3654 for instance an OS kernel and a RAMDisk image.
3656 "Multi-File Images" start with a list of image sizes, each
3657 image size (in bytes) specified by an "uint32_t" in network
3658 byte order. This list is terminated by an "(uint32_t)0".
3659 Immediately after the terminating 0 follow the images, one by
3660 one, all aligned on "uint32_t" boundaries (size rounded up to
3661 a multiple of 4 bytes).
3663 "Firmware Images" are binary images containing firmware (like
3664 U-Boot or FPGA images) which usually will be programmed to
3667 "Script files" are command sequences that will be executed by
3668 U-Boot's command interpreter; this feature is especially
3669 useful when you configure U-Boot to use a real shell (hush)
3670 as command interpreter.
3676 One of the features of U-Boot is that you can dynamically load and
3677 run "standalone" applications, which can use some resources of
3678 U-Boot like console I/O functions or interrupt services.
3680 Two simple examples are included with the sources:
3685 'examples/hello_world.c' contains a small "Hello World" Demo
3686 application; it is automatically compiled when you build U-Boot.
3687 It's configured to run at address 0x00040004, so you can play with it
3691 ## Ready for S-Record download ...
3692 ~>examples/hello_world.srec
3693 1 2 3 4 5 6 7 8 9 10 11 ...
3694 [file transfer complete]
3696 ## Start Addr = 0x00040004
3698 => go 40004 Hello World! This is a test.
3699 ## Starting application at 0x00040004 ...
3710 Hit any key to exit ...
3712 ## Application terminated, rc = 0x0
3714 Another example, which demonstrates how to register a CPM interrupt
3715 handler with the U-Boot code, can be found in 'examples/timer.c'.
3716 Here, a CPM timer is set up to generate an interrupt every second.
3717 The interrupt service routine is trivial, just printing a '.'
3718 character, but this is just a demo program. The application can be
3719 controlled by the following keys:
3721 ? - print current values og the CPM Timer registers
3722 b - enable interrupts and start timer
3723 e - stop timer and disable interrupts
3724 q - quit application
3727 ## Ready for S-Record download ...
3728 ~>examples/timer.srec
3729 1 2 3 4 5 6 7 8 9 10 11 ...
3730 [file transfer complete]
3732 ## Start Addr = 0x00040004
3735 ## Starting application at 0x00040004 ...
3738 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3741 [q, b, e, ?] Set interval 1000000 us
3744 [q, b, e, ?] ........
3745 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3748 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3751 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3754 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3756 [q, b, e, ?] ...Stopping timer
3758 [q, b, e, ?] ## Application terminated, rc = 0x0
3764 Over time, many people have reported problems when trying to use the
3765 "minicom" terminal emulation program for serial download. I (wd)
3766 consider minicom to be broken, and recommend not to use it. Under
3767 Unix, I recommend to use C-Kermit for general purpose use (and
3768 especially for kermit binary protocol download ("loadb" command), and
3769 use "cu" for S-Record download ("loads" command).
3771 Nevertheless, if you absolutely want to use it try adding this
3772 configuration to your "File transfer protocols" section:
3774 Name Program Name U/D FullScr IO-Red. Multi
3775 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3776 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3782 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3783 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3785 Building requires a cross environment; it is known to work on
3786 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3787 need gmake since the Makefiles are not compatible with BSD make).
3788 Note that the cross-powerpc package does not install include files;
3789 attempting to build U-Boot will fail because <machine/ansi.h> is
3790 missing. This file has to be installed and patched manually:
3792 # cd /usr/pkg/cross/powerpc-netbsd/include
3794 # ln -s powerpc machine
3795 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3796 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3798 Native builds *don't* work due to incompatibilities between native
3799 and U-Boot include files.
3801 Booting assumes that (the first part of) the image booted is a
3802 stage-2 loader which in turn loads and then invokes the kernel
3803 proper. Loader sources will eventually appear in the NetBSD source
3804 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3805 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3808 Implementation Internals:
3809 =========================
3811 The following is not intended to be a complete description of every
3812 implementation detail. However, it should help to understand the
3813 inner workings of U-Boot and make it easier to port it to custom
3817 Initial Stack, Global Data:
3818 ---------------------------
3820 The implementation of U-Boot is complicated by the fact that U-Boot
3821 starts running out of ROM (flash memory), usually without access to
3822 system RAM (because the memory controller is not initialized yet).
3823 This means that we don't have writable Data or BSS segments, and BSS
3824 is not initialized as zero. To be able to get a C environment working
3825 at all, we have to allocate at least a minimal stack. Implementation
3826 options for this are defined and restricted by the CPU used: Some CPU
3827 models provide on-chip memory (like the IMMR area on MPC8xx and
3828 MPC826x processors), on others (parts of) the data cache can be
3829 locked as (mis-) used as memory, etc.
3831 Chris Hallinan posted a good summary of these issues to the
3832 U-Boot mailing list:
3834 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3835 From: "Chris Hallinan" <clh@net1plus.com>
3836 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3839 Correct me if I'm wrong, folks, but the way I understand it
3840 is this: Using DCACHE as initial RAM for Stack, etc, does not
3841 require any physical RAM backing up the cache. The cleverness
3842 is that the cache is being used as a temporary supply of
3843 necessary storage before the SDRAM controller is setup. It's
3844 beyond the scope of this list to explain the details, but you
3845 can see how this works by studying the cache architecture and
3846 operation in the architecture and processor-specific manuals.
3848 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3849 is another option for the system designer to use as an
3850 initial stack/RAM area prior to SDRAM being available. Either
3851 option should work for you. Using CS 4 should be fine if your
3852 board designers haven't used it for something that would
3853 cause you grief during the initial boot! It is frequently not
3856 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
3857 with your processor/board/system design. The default value
3858 you will find in any recent u-boot distribution in
3859 walnut.h should work for you. I'd set it to a value larger
3860 than your SDRAM module. If you have a 64MB SDRAM module, set
3861 it above 400_0000. Just make sure your board has no resources
3862 that are supposed to respond to that address! That code in
3863 start.S has been around a while and should work as is when
3864 you get the config right.
3869 It is essential to remember this, since it has some impact on the C
3870 code for the initialization procedures:
3872 * Initialized global data (data segment) is read-only. Do not attempt
3875 * Do not use any uninitialized global data (or implicitely initialized
3876 as zero data - BSS segment) at all - this is undefined, initiali-
3877 zation is performed later (when relocating to RAM).
3879 * Stack space is very limited. Avoid big data buffers or things like
3882 Having only the stack as writable memory limits means we cannot use
3883 normal global data to share information beween the code. But it
3884 turned out that the implementation of U-Boot can be greatly
3885 simplified by making a global data structure (gd_t) available to all
3886 functions. We could pass a pointer to this data as argument to _all_
3887 functions, but this would bloat the code. Instead we use a feature of
3888 the GCC compiler (Global Register Variables) to share the data: we
3889 place a pointer (gd) to the global data into a register which we
3890 reserve for this purpose.
3892 When choosing a register for such a purpose we are restricted by the
3893 relevant (E)ABI specifications for the current architecture, and by
3894 GCC's implementation.
3896 For PowerPC, the following registers have specific use:
3898 R2: reserved for system use
3899 R3-R4: parameter passing and return values
3900 R5-R10: parameter passing
3901 R13: small data area pointer
3905 (U-Boot also uses R14 as internal GOT pointer.)
3907 ==> U-Boot will use R2 to hold a pointer to the global data
3909 Note: on PPC, we could use a static initializer (since the
3910 address of the global data structure is known at compile time),
3911 but it turned out that reserving a register results in somewhat
3912 smaller code - although the code savings are not that big (on
3913 average for all boards 752 bytes for the whole U-Boot image,
3914 624 text + 127 data).
3916 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
3917 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
3919 ==> U-Boot will use P3 to hold a pointer to the global data
3921 On ARM, the following registers are used:
3923 R0: function argument word/integer result
3924 R1-R3: function argument word
3926 R10: stack limit (used only if stack checking if enabled)
3927 R11: argument (frame) pointer
3928 R12: temporary workspace
3931 R15: program counter
3933 ==> U-Boot will use R8 to hold a pointer to the global data
3935 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
3936 or current versions of GCC may "optimize" the code too much.
3941 U-Boot runs in system state and uses physical addresses, i.e. the
3942 MMU is not used either for address mapping nor for memory protection.
3944 The available memory is mapped to fixed addresses using the memory
3945 controller. In this process, a contiguous block is formed for each
3946 memory type (Flash, SDRAM, SRAM), even when it consists of several
3947 physical memory banks.
3949 U-Boot is installed in the first 128 kB of the first Flash bank (on
3950 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3951 booting and sizing and initializing DRAM, the code relocates itself
3952 to the upper end of DRAM. Immediately below the U-Boot code some
3953 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
3954 configuration setting]. Below that, a structure with global Board
3955 Info data is placed, followed by the stack (growing downward).
3957 Additionally, some exception handler code is copied to the low 8 kB
3958 of DRAM (0x00000000 ... 0x00001FFF).
3960 So a typical memory configuration with 16 MB of DRAM could look like
3963 0x0000 0000 Exception Vector code
3966 0x0000 2000 Free for Application Use
3972 0x00FB FF20 Monitor Stack (Growing downward)
3973 0x00FB FFAC Board Info Data and permanent copy of global data
3974 0x00FC 0000 Malloc Arena
3977 0x00FE 0000 RAM Copy of Monitor Code
3978 ... eventually: LCD or video framebuffer
3979 ... eventually: pRAM (Protected RAM - unchanged by reset)
3980 0x00FF FFFF [End of RAM]
3983 System Initialization:
3984 ----------------------
3986 In the reset configuration, U-Boot starts at the reset entry point
3987 (on most PowerPC systems at address 0x00000100). Because of the reset
3988 configuration for CS0# this is a mirror of the onboard Flash memory.
3989 To be able to re-map memory U-Boot then jumps to its link address.
3990 To be able to implement the initialization code in C, a (small!)
3991 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3992 which provide such a feature like MPC8xx or MPC8260), or in a locked
3993 part of the data cache. After that, U-Boot initializes the CPU core,
3994 the caches and the SIU.
3996 Next, all (potentially) available memory banks are mapped using a
3997 preliminary mapping. For example, we put them on 512 MB boundaries
3998 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3999 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4000 programmed for SDRAM access. Using the temporary configuration, a
4001 simple memory test is run that determines the size of the SDRAM
4004 When there is more than one SDRAM bank, and the banks are of
4005 different size, the largest is mapped first. For equal size, the first
4006 bank (CS2#) is mapped first. The first mapping is always for address
4007 0x00000000, with any additional banks following immediately to create
4008 contiguous memory starting from 0.
4010 Then, the monitor installs itself at the upper end of the SDRAM area
4011 and allocates memory for use by malloc() and for the global Board
4012 Info data; also, the exception vector code is copied to the low RAM
4013 pages, and the final stack is set up.
4015 Only after this relocation will you have a "normal" C environment;
4016 until that you are restricted in several ways, mostly because you are
4017 running from ROM, and because the code will have to be relocated to a
4021 U-Boot Porting Guide:
4022 ----------------------
4024 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4028 int main(int argc, char *argv[])
4030 sighandler_t no_more_time;
4032 signal(SIGALRM, no_more_time);
4033 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4035 if (available_money > available_manpower) {
4036 Pay consultant to port U-Boot;
4040 Download latest U-Boot source;
4042 Subscribe to u-boot mailing list;
4045 email("Hi, I am new to U-Boot, how do I get started?");
4048 Read the README file in the top level directory;
4049 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4050 Read applicable doc/*.README;
4051 Read the source, Luke;
4052 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4055 if (available_money > toLocalCurrency ($2500))
4058 Add a lot of aggravation and time;
4060 if (a similar board exists) { /* hopefully... */
4061 cp -a board/<similar> board/<myboard>
4062 cp include/configs/<similar>.h include/configs/<myboard>.h
4064 Create your own board support subdirectory;
4065 Create your own board include/configs/<myboard>.h file;
4067 Edit new board/<myboard> files
4068 Edit new include/configs/<myboard>.h
4073 Add / modify source code;
4077 email("Hi, I am having problems...");
4079 Send patch file to the U-Boot email list;
4080 if (reasonable critiques)
4081 Incorporate improvements from email list code review;
4083 Defend code as written;
4089 void no_more_time (int sig)
4098 All contributions to U-Boot should conform to the Linux kernel
4099 coding style; see the file "Documentation/CodingStyle" and the script
4100 "scripts/Lindent" in your Linux kernel source directory. In sources
4101 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4102 spaces before parameters to function calls) is actually used.
4104 Source files originating from a different project (for example the
4105 MTD subsystem) are generally exempt from these guidelines and are not
4106 reformated to ease subsequent migration to newer versions of those
4109 Please note that U-Boot is implemented in C (and to some small parts in
4110 Assembler); no C++ is used, so please do not use C++ style comments (//)
4113 Please also stick to the following formatting rules:
4114 - remove any trailing white space
4115 - use TAB characters for indentation, not spaces
4116 - make sure NOT to use DOS '\r\n' line feeds
4117 - do not add more than 2 empty lines to source files
4118 - do not add trailing empty lines to source files
4120 Submissions which do not conform to the standards may be returned
4121 with a request to reformat the changes.
4127 Since the number of patches for U-Boot is growing, we need to
4128 establish some rules. Submissions which do not conform to these rules
4129 may be rejected, even when they contain important and valuable stuff.
4131 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4133 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4134 see http://lists.denx.de/mailman/listinfo/u-boot
4136 When you send a patch, please include the following information with
4139 * For bug fixes: a description of the bug and how your patch fixes
4140 this bug. Please try to include a way of demonstrating that the
4141 patch actually fixes something.
4143 * For new features: a description of the feature and your
4146 * A CHANGELOG entry as plaintext (separate from the patch)
4148 * For major contributions, your entry to the CREDITS file
4150 * When you add support for a new board, don't forget to add this
4151 board to the MAKEALL script, too.
4153 * If your patch adds new configuration options, don't forget to
4154 document these in the README file.
4156 * The patch itself. If you are using git (which is *strongly*
4157 recommended) you can easily generate the patch using the
4158 "git-format-patch". If you then use "git-send-email" to send it to
4159 the U-Boot mailing list, you will avoid most of the common problems
4160 with some other mail clients.
4162 If you cannot use git, use "diff -purN OLD NEW". If your version of
4163 diff does not support these options, then get the latest version of
4166 The current directory when running this command shall be the parent
4167 directory of the U-Boot source tree (i. e. please make sure that
4168 your patch includes sufficient directory information for the
4171 We prefer patches as plain text. MIME attachments are discouraged,
4172 and compressed attachments must not be used.
4174 * If one logical set of modifications affects or creates several
4175 files, all these changes shall be submitted in a SINGLE patch file.
4177 * Changesets that contain different, unrelated modifications shall be
4178 submitted as SEPARATE patches, one patch per changeset.
4183 * Before sending the patch, run the MAKEALL script on your patched
4184 source tree and make sure that no errors or warnings are reported
4185 for any of the boards.
4187 * Keep your modifications to the necessary minimum: A patch
4188 containing several unrelated changes or arbitrary reformats will be
4189 returned with a request to re-formatting / split it.
4191 * If you modify existing code, make sure that your new code does not
4192 add to the memory footprint of the code ;-) Small is beautiful!
4193 When adding new features, these should compile conditionally only
4194 (using #ifdef), and the resulting code with the new feature
4195 disabled must not need more memory than the old code without your
4198 * Remember that there is a size limit of 100 kB per message on the
4199 u-boot mailing list. Bigger patches will be moderated. If they are
4200 reasonable and not too big, they will be acknowledged. But patches
4201 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob