2 # (C) Copyright 2000 - 2005
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.
60 In case you have questions about, problems with or contributions for
61 U-Boot you should send a message to the U-Boot mailing list at
62 <u-boot-users@lists.sourceforge.net>. There is also an archive of
63 previous traffic on the mailing list - please search the archive
64 before asking FAQ's. Please see
65 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
71 - start from 8xxrom sources
72 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
74 - make it easier to add custom boards
75 - make it possible to add other [PowerPC] CPUs
76 - extend functions, especially:
77 * Provide extended interface to Linux boot loader
80 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
81 - create ARMBoot project (http://sourceforge.net/projects/armboot)
82 - add other CPU families (starting with ARM)
83 - create U-Boot project (http://sourceforge.net/projects/u-boot)
89 The "official" name of this project is "Das U-Boot". The spelling
90 "U-Boot" shall be used in all written text (documentation, comments
91 in source files etc.). Example:
93 This is the README file for the U-Boot project.
95 File names etc. shall be based on the string "u-boot". Examples:
97 include/asm-ppc/u-boot.h
99 #include <asm/u-boot.h>
101 Variable names, preprocessor constants etc. shall be either based on
102 the string "u_boot" or on "U_BOOT". Example:
104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
111 U-Boot uses a 3 level version number containing a version, a
112 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
113 sub-version "34", and patchlevel "4".
115 The patchlevel is used to indicate certain stages of development
116 between released versions, i. e. officially released versions of
117 U-Boot will always have a patchlevel of "0".
123 - board Board dependent files
124 - common Misc architecture independent functions
125 - cpu CPU specific files
126 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
127 - arm720t Files specific to ARM 720 CPUs
128 - arm920t Files specific to ARM 920 CPUs
129 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
130 - imx Files specific to Freescale MC9328 i.MX CPUs
131 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
132 - arm925t Files specific to ARM 925 CPUs
133 - arm926ejs Files specific to ARM 926 CPUs
134 - arm1136 Files specific to ARM 1136 CPUs
135 - at32ap Files specific to Atmel AVR32 AP CPUs
136 - i386 Files specific to i386 CPUs
137 - ixp Files specific to Intel XScale IXP CPUs
138 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
139 - mips Files specific to MIPS CPUs
140 - mpc5xx Files specific to Freescale MPC5xx CPUs
141 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
142 - mpc8xx Files specific to Freescale MPC8xx CPUs
143 - mpc8220 Files specific to Freescale MPC8220 CPUs
144 - mpc824x Files specific to Freescale MPC824x CPUs
145 - mpc8260 Files specific to Freescale MPC8260 CPUs
146 - mpc85xx Files specific to Freescale MPC85xx CPUs
147 - nios Files specific to Altera NIOS CPUs
148 - nios2 Files specific to Altera Nios-II CPUs
149 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
150 - pxa Files specific to Intel XScale PXA CPUs
151 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
152 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
153 - disk Code for disk drive partition handling
154 - doc Documentation (don't expect too much)
155 - drivers Commonly used device drivers
156 - dtt Digital Thermometer and Thermostat drivers
157 - examples Example code for standalone applications, etc.
158 - include Header Files
159 - lib_arm Files generic to ARM architecture
160 - lib_avr32 Files generic to AVR32 architecture
161 - lib_generic Files generic to all architectures
162 - lib_i386 Files generic to i386 architecture
163 - lib_m68k Files generic to m68k architecture
164 - lib_mips Files generic to MIPS architecture
165 - lib_nios Files generic to NIOS architecture
166 - lib_ppc Files generic to PowerPC architecture
167 - net Networking code
168 - post Power On Self Test
169 - rtc Real Time Clock drivers
170 - tools Tools to build S-Record or U-Boot images, etc.
172 Software Configuration:
173 =======================
175 Configuration is usually done using C preprocessor defines; the
176 rationale behind that is to avoid dead code whenever possible.
178 There are two classes of configuration variables:
180 * Configuration _OPTIONS_:
181 These are selectable by the user and have names beginning with
184 * Configuration _SETTINGS_:
185 These depend on the hardware etc. and should not be meddled with if
186 you don't know what you're doing; they have names beginning with
189 Later we will add a configuration tool - probably similar to or even
190 identical to what's used for the Linux kernel. Right now, we have to
191 do the configuration by hand, which means creating some symbolic
192 links and editing some configuration files. We use the TQM8xxL boards
196 Selection of Processor Architecture and Board Type:
197 ---------------------------------------------------
199 For all supported boards there are ready-to-use default
200 configurations available; just type "make <board_name>_config".
202 Example: For a TQM823L module type:
207 For the Cogent platform, you need to specify the cpu type as well;
208 e.g. "make cogent_mpc8xx_config". And also configure the cogent
209 directory according to the instructions in cogent/README.
212 Configuration Options:
213 ----------------------
215 Configuration depends on the combination of board and CPU type; all
216 such information is kept in a configuration file
217 "include/configs/<board_name>.h".
219 Example: For a TQM823L module, all configuration settings are in
220 "include/configs/TQM823L.h".
223 Many of the options are named exactly as the corresponding Linux
224 kernel configuration options. The intention is to make it easier to
225 build a config tool - later.
228 The following options need to be configured:
230 - CPU Type: Define exactly one of
234 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
237 or CONFIG_MPC824X, CONFIG_MPC8260
253 MicroBlaze based CPUs:
254 ----------------------
258 ----------------------
262 ----------------------
265 - Board Type: Define exactly one of
267 PowerPC based boards:
268 ---------------------
270 CONFIG_ADCIOP CONFIG_FPS860L CONFIG_OXC
271 CONFIG_ADS860 CONFIG_GEN860T CONFIG_PCI405
272 CONFIG_AMX860 CONFIG_GENIETV CONFIG_PCIPPC2
273 CONFIG_AP1000 CONFIG_GTH CONFIG_PCIPPC6
274 CONFIG_AR405 CONFIG_gw8260 CONFIG_pcu_e
275 CONFIG_BAB7xx CONFIG_hermes CONFIG_PIP405
276 CONFIG_BC3450 CONFIG_hymod CONFIG_PM826
277 CONFIG_c2mon CONFIG_IAD210 CONFIG_ppmc8260
278 CONFIG_CANBT CONFIG_ICU862 CONFIG_QS823
279 CONFIG_CCM CONFIG_IP860 CONFIG_QS850
280 CONFIG_CMI CONFIG_IPHASE4539 CONFIG_QS860T
281 CONFIG_cogent_mpc8260 CONFIG_IVML24 CONFIG_RBC823
282 CONFIG_cogent_mpc8xx CONFIG_IVML24_128 CONFIG_RPXClassic
283 CONFIG_CPCI405 CONFIG_IVML24_256 CONFIG_RPXlite
284 CONFIG_CPCI4052 CONFIG_IVMS8 CONFIG_RPXsuper
285 CONFIG_CPCIISER4 CONFIG_IVMS8_128 CONFIG_rsdproto
286 CONFIG_CPU86 CONFIG_IVMS8_256 CONFIG_sacsng
287 CONFIG_CRAYL1 CONFIG_JSE CONFIG_Sandpoint8240
288 CONFIG_CSB272 CONFIG_LANTEC CONFIG_Sandpoint8245
289 CONFIG_CU824 CONFIG_LITE5200B CONFIG_sbc8260
290 CONFIG_DASA_SIM CONFIG_lwmon CONFIG_sbc8560
291 CONFIG_DB64360 CONFIG_MBX CONFIG_SM850
292 CONFIG_DB64460 CONFIG_MBX860T CONFIG_SPD823TS
293 CONFIG_DU405 CONFIG_MHPC CONFIG_STXGP3
294 CONFIG_DUET_ADS CONFIG_MIP405 CONFIG_SXNI855T
295 CONFIG_EBONY CONFIG_MOUSSE CONFIG_TQM823L
296 CONFIG_ELPPC CONFIG_MPC8260ADS CONFIG_TQM8260
297 CONFIG_ELPT860 CONFIG_MPC8540ADS CONFIG_TQM850L
298 CONFIG_ep8260 CONFIG_MPC8540EVAL CONFIG_TQM855L
299 CONFIG_ERIC CONFIG_MPC8560ADS CONFIG_TQM860L
300 CONFIG_ESTEEM192E CONFIG_MUSENKI CONFIG_TTTech
301 CONFIG_ETX094 CONFIG_MVS1 CONFIG_UTX8245
302 CONFIG_EVB64260 CONFIG_NETPHONE CONFIG_V37
303 CONFIG_FADS823 CONFIG_NETTA CONFIG_W7OLMC
304 CONFIG_FADS850SAR CONFIG_NETVIA CONFIG_W7OLMG
305 CONFIG_FADS860T CONFIG_NX823 CONFIG_WALNUT
306 CONFIG_FLAGADM CONFIG_OCRTC CONFIG_ZPC1900
307 CONFIG_FPS850L CONFIG_ORSG CONFIG_ZUMA
312 CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250,
313 CONFIG_CSB637, CONFIG_DELTA, CONFIG_DNP1110,
314 CONFIG_EP7312, CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE,
315 CONFIG_IMPA7, CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610,
316 CONFIG_KB9202, CONFIG_LART, CONFIG_LPD7A400,
317 CONFIG_LUBBOCK, CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4,
318 CONFIG_PLEB2, CONFIG_SHANNON, CONFIG_P2_OMAP730,
319 CONFIG_SMDK2400, CONFIG_SMDK2410, CONFIG_TRAB,
322 MicroBlaze based boards:
323 ------------------------
328 ------------------------
330 CONFIG_PCI5441 CONFIG_PK1C20
331 CONFIG_EP1C20 CONFIG_EP1S10 CONFIG_EP1S40
338 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
339 Define exactly one of
343 - CPU Module Type: (if CONFIG_COGENT is defined)
344 Define exactly one of
346 --- FIXME --- not tested yet:
347 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
348 CONFIG_CMA287_23, CONFIG_CMA287_50
350 - Motherboard Type: (if CONFIG_COGENT is defined)
351 Define exactly one of
352 CONFIG_CMA101, CONFIG_CMA102
354 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
355 Define one or more of
358 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
359 Define one or more of
360 CONFIG_LCD_HEARTBEAT - update a character position on
361 the lcd display every second with
364 - Board flavour: (if CONFIG_MPC8260ADS is defined)
367 CFG_8260ADS - original MPC8260ADS
368 CFG_8266ADS - MPC8266ADS
369 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
370 CFG_8272ADS - MPC8272ADS
372 - MPC824X Family Member (if CONFIG_MPC824X is defined)
373 Define exactly one of
374 CONFIG_MPC8240, CONFIG_MPC8245
376 - 8xx CPU Options: (if using an MPC8xx cpu)
377 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
378 get_gclk_freq() cannot work
379 e.g. if there is no 32KHz
380 reference PIT/RTC clock
381 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
384 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
387 CONFIG_8xx_CPUCLK_DEFAULT
388 See doc/README.MPC866
392 Define this to measure the actual CPU clock instead
393 of relying on the correctness of the configured
394 values. Mostly useful for board bringup to make sure
395 the PLL is locked at the intended frequency. Note
396 that this requires a (stable) reference clock (32 kHz
397 RTC clock or CFG_8XX_XIN)
399 - Intel Monahans options:
400 CFG_MONAHANS_RUN_MODE_OSC_RATIO
402 Defines the Monahans run mode to oscillator
403 ratio. Valid values are 8, 16, 24, 31. The core
404 frequency is this value multiplied by 13 MHz.
406 CFG_MONAHANS_TURBO_RUN_MODE_RATIO
408 Defines the Monahans turbo mode to oscillator
409 ratio. Valid values are 1 (default if undefined) and
410 2. The core frequency as calculated above is multiplied
413 - Linux Kernel Interface:
416 U-Boot stores all clock information in Hz
417 internally. For binary compatibility with older Linux
418 kernels (which expect the clocks passed in the
419 bd_info data to be in MHz) the environment variable
420 "clocks_in_mhz" can be defined so that U-Boot
421 converts clock data to MHZ before passing it to the
423 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
424 "clocks_in_mhz=1" is automatically included in the
427 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
429 When transfering memsize parameter to linux, some versions
430 expect it to be in bytes, others in MB.
431 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
435 New kernel versions are expecting firmware settings to be
436 passed using flat open firmware trees.
437 The environment variable "disable_of", when set, disables this
440 CONFIG_OF_FLAT_TREE_MAX_SIZE
442 The maximum size of the constructed OF tree.
444 OF_CPU - The proper name of the cpus node.
445 OF_SOC - The proper name of the soc node.
446 OF_TBCLK - The timebase frequency.
447 OF_STDOUT_PATH - The path to the console device
451 The resulting flat device tree will have a copy of the bd_t.
452 Space should be pre-allocated in the dts for the bd_t.
454 CONFIG_OF_HAS_UBOOT_ENV
456 The resulting flat device tree will have a copy of u-boot's
457 environment variables
459 CONFIG_OF_BOARD_SETUP
461 Board code has addition modification that it wants to make
462 to the flat device tree before handing it off to the kernel
467 Define this if you want support for Amba PrimeCell PL010 UARTs.
471 Define this if you want support for Amba PrimeCell PL011 UARTs.
475 If you have Amba PrimeCell PL011 UARTs, set this variable to
476 the clock speed of the UARTs.
480 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
481 define this to a list of base addresses for each (supported)
482 port. See e.g. include/configs/versatile.h
486 Depending on board, define exactly one serial port
487 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
488 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
489 console by defining CONFIG_8xx_CONS_NONE
491 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
492 port routines must be defined elsewhere
493 (i.e. serial_init(), serial_getc(), ...)
496 Enables console device for a color framebuffer. Needs following
497 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
498 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
500 VIDEO_HW_RECTFILL graphic chip supports
503 VIDEO_HW_BITBLT graphic chip supports
504 bit-blit (cf. smiLynxEM)
505 VIDEO_VISIBLE_COLS visible pixel columns
507 VIDEO_VISIBLE_ROWS visible pixel rows
508 VIDEO_PIXEL_SIZE bytes per pixel
509 VIDEO_DATA_FORMAT graphic data format
510 (0-5, cf. cfb_console.c)
511 VIDEO_FB_ADRS framebuffer address
512 VIDEO_KBD_INIT_FCT keyboard int fct
513 (i.e. i8042_kbd_init())
514 VIDEO_TSTC_FCT test char fct
516 VIDEO_GETC_FCT get char fct
518 CONFIG_CONSOLE_CURSOR cursor drawing on/off
519 (requires blink timer
521 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
522 CONFIG_CONSOLE_TIME display time/date info in
524 (requires CFG_CMD_DATE)
525 CONFIG_VIDEO_LOGO display Linux logo in
527 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
528 linux_logo.h for logo.
529 Requires CONFIG_VIDEO_LOGO
530 CONFIG_CONSOLE_EXTRA_INFO
531 addional board info beside
534 When CONFIG_CFB_CONSOLE is defined, video console is
535 default i/o. Serial console can be forced with
536 environment 'console=serial'.
538 When CONFIG_SILENT_CONSOLE is defined, all console
539 messages (by U-Boot and Linux!) can be silenced with
540 the "silent" environment variable. See
541 doc/README.silent for more information.
544 CONFIG_BAUDRATE - in bps
545 Select one of the baudrates listed in
546 CFG_BAUDRATE_TABLE, see below.
547 CFG_BRGCLK_PRESCALE, baudrate prescale
549 - Interrupt driven serial port input:
550 CONFIG_SERIAL_SOFTWARE_FIFO
553 Use an interrupt handler for receiving data on the
554 serial port. It also enables using hardware handshake
555 (RTS/CTS) and UART's built-in FIFO. Set the number of
556 bytes the interrupt driven input buffer should have.
558 Leave undefined to disable this feature, including
559 disable the buffer and hardware handshake.
561 - Console UART Number:
565 If defined internal UART1 (and not UART0) is used
566 as default U-Boot console.
568 - Boot Delay: CONFIG_BOOTDELAY - in seconds
569 Delay before automatically booting the default image;
570 set to -1 to disable autoboot.
572 See doc/README.autoboot for these options that
573 work with CONFIG_BOOTDELAY. None are required.
574 CONFIG_BOOT_RETRY_TIME
575 CONFIG_BOOT_RETRY_MIN
576 CONFIG_AUTOBOOT_KEYED
577 CONFIG_AUTOBOOT_PROMPT
578 CONFIG_AUTOBOOT_DELAY_STR
579 CONFIG_AUTOBOOT_STOP_STR
580 CONFIG_AUTOBOOT_DELAY_STR2
581 CONFIG_AUTOBOOT_STOP_STR2
582 CONFIG_ZERO_BOOTDELAY_CHECK
583 CONFIG_RESET_TO_RETRY
587 Only needed when CONFIG_BOOTDELAY is enabled;
588 define a command string that is automatically executed
589 when no character is read on the console interface
590 within "Boot Delay" after reset.
593 This can be used to pass arguments to the bootm
594 command. The value of CONFIG_BOOTARGS goes into the
595 environment value "bootargs".
597 CONFIG_RAMBOOT and CONFIG_NFSBOOT
598 The value of these goes into the environment as
599 "ramboot" and "nfsboot" respectively, and can be used
600 as a convenience, when switching between booting from
606 When this option is #defined, the existence of the
607 environment variable "preboot" will be checked
608 immediately before starting the CONFIG_BOOTDELAY
609 countdown and/or running the auto-boot command resp.
610 entering interactive mode.
612 This feature is especially useful when "preboot" is
613 automatically generated or modified. For an example
614 see the LWMON board specific code: here "preboot" is
615 modified when the user holds down a certain
616 combination of keys on the (special) keyboard when
619 - Serial Download Echo Mode:
621 If defined to 1, all characters received during a
622 serial download (using the "loads" command) are
623 echoed back. This might be needed by some terminal
624 emulations (like "cu"), but may as well just take
625 time on others. This setting #define's the initial
626 value of the "loads_echo" environment variable.
628 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
630 Select one of the baudrates listed in
631 CFG_BAUDRATE_TABLE, see below.
635 Most monitor functions can be selected (or
636 de-selected) by adjusting the definition of
637 CONFIG_COMMANDS; to select individual functions,
638 #define CONFIG_COMMANDS by "OR"ing any of the
641 #define enables commands:
642 -------------------------
643 CFG_CMD_ASKENV * ask for env variable
644 CFG_CMD_AUTOSCRIPT Autoscript Support
646 CFG_CMD_BEDBUG * Include BedBug Debugger
647 CFG_CMD_BMP * BMP support
648 CFG_CMD_BSP * Board specific commands
650 CFG_CMD_CACHE * icache, dcache
651 CFG_CMD_CONSOLE coninfo
652 CFG_CMD_DATE * support for RTC, date/time...
653 CFG_CMD_DHCP * DHCP support
654 CFG_CMD_DIAG * Diagnostics
655 CFG_CMD_DOC * Disk-On-Chip Support
656 CFG_CMD_DTT * Digital Therm and Thermostat
657 CFG_CMD_ECHO echo arguments
658 CFG_CMD_EEPROM * EEPROM read/write support
659 CFG_CMD_ELF * bootelf, bootvx
661 CFG_CMD_FDC * Floppy Disk Support
662 CFG_CMD_FAT * FAT partition support
663 CFG_CMD_FDOS * Dos diskette Support
664 CFG_CMD_FLASH flinfo, erase, protect
665 CFG_CMD_FPGA FPGA device initialization support
666 CFG_CMD_HWFLOW * RTS/CTS hw flow control
667 CFG_CMD_I2C * I2C serial bus support
668 CFG_CMD_IDE * IDE harddisk support
670 CFG_CMD_IMLS List all found images
671 CFG_CMD_IMMAP * IMMR dump support
672 CFG_CMD_IRQ * irqinfo
673 CFG_CMD_ITEST Integer/string test of 2 values
674 CFG_CMD_JFFS2 * JFFS2 Support
678 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
680 CFG_CMD_MISC Misc functions like sleep etc
681 CFG_CMD_MMC * MMC memory mapped support
682 CFG_CMD_MII * MII utility commands
683 CFG_CMD_NAND * NAND support
684 CFG_CMD_NET bootp, tftpboot, rarpboot
685 CFG_CMD_PCI * pciinfo
686 CFG_CMD_PCMCIA * PCMCIA support
687 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
688 CFG_CMD_PORTIO * Port I/O
689 CFG_CMD_REGINFO * Register dump
690 CFG_CMD_RUN run command in env variable
691 CFG_CMD_SAVES * save S record dump
692 CFG_CMD_SCSI * SCSI Support
693 CFG_CMD_SDRAM * print SDRAM configuration information
694 (requires CFG_CMD_I2C)
695 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
696 CFG_CMD_SPI * SPI serial bus support
697 CFG_CMD_USB * USB support
698 CFG_CMD_VFD * VFD support (TRAB)
699 CFG_CMD_BSP * Board SPecific functions
700 CFG_CMD_CDP * Cisco Discover Protocol support
701 -----------------------------------------------
704 CONFIG_CMD_DFL Default configuration; at the moment
705 this is includes all commands, except
706 the ones marked with "*" in the list
709 If you don't define CONFIG_COMMANDS it defaults to
710 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
711 override the default settings in the respective
714 EXAMPLE: If you want all functions except of network
715 support you can write:
717 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
720 Note: Don't enable the "icache" and "dcache" commands
721 (configuration option CFG_CMD_CACHE) unless you know
722 what you (and your U-Boot users) are doing. Data
723 cache cannot be enabled on systems like the 8xx or
724 8260 (where accesses to the IMMR region must be
725 uncached), and it cannot be disabled on all other
726 systems where we (mis-) use the data cache to hold an
727 initial stack and some data.
730 XXX - this list needs to get updated!
734 If this variable is defined, it enables watchdog
735 support. There must be support in the platform specific
736 code for a watchdog. For the 8xx and 8260 CPUs, the
737 SIU Watchdog feature is enabled in the SYPCR
741 CONFIG_VERSION_VARIABLE
742 If this variable is defined, an environment variable
743 named "ver" is created by U-Boot showing the U-Boot
744 version as printed by the "version" command.
745 This variable is readonly.
749 When CFG_CMD_DATE is selected, the type of the RTC
750 has to be selected, too. Define exactly one of the
753 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
754 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
755 CONFIG_RTC_MC146818 - use MC146818 RTC
756 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
757 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
758 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
759 CONFIG_RTC_DS164x - use Dallas DS164x RTC
760 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
762 Note that if the RTC uses I2C, then the I2C interface
763 must also be configured. See I2C Support, below.
767 When CONFIG_TIMESTAMP is selected, the timestamp
768 (date and time) of an image is printed by image
769 commands like bootm or iminfo. This option is
770 automatically enabled when you select CFG_CMD_DATE .
773 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
774 and/or CONFIG_ISO_PARTITION
776 If IDE or SCSI support is enabled (CFG_CMD_IDE or
777 CFG_CMD_SCSI) you must configure support for at least
778 one partition type as well.
781 CONFIG_IDE_RESET_ROUTINE - this is defined in several
782 board configurations files but used nowhere!
784 CONFIG_IDE_RESET - is this is defined, IDE Reset will
785 be performed by calling the function
786 ide_set_reset(int reset)
787 which has to be defined in a board specific file
792 Set this to enable ATAPI support.
797 Set this to enable support for disks larger than 137GB
798 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
799 Whithout these , LBA48 support uses 32bit variables and will 'only'
800 support disks up to 2.1TB.
803 When enabled, makes the IDE subsystem use 64bit sector addresses.
807 At the moment only there is only support for the
808 SYM53C8XX SCSI controller; define
809 CONFIG_SCSI_SYM53C8XX to enable it.
811 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
812 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
813 CFG_SCSI_MAX_LUN] can be adjusted to define the
814 maximum numbers of LUNs, SCSI ID's and target
816 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
818 - NETWORK Support (PCI):
820 Support for Intel 8254x gigabit chips.
823 Support for Intel 82557/82559/82559ER chips.
824 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
825 write routine for first time initialisation.
828 Support for Digital 2114x chips.
829 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
830 modem chip initialisation (KS8761/QS6611).
833 Support for National dp83815 chips.
836 Support for National dp8382[01] gigabit chips.
838 - NETWORK Support (other):
840 CONFIG_DRIVER_LAN91C96
841 Support for SMSC's LAN91C96 chips.
844 Define this to hold the physical address
845 of the LAN91C96's I/O space
847 CONFIG_LAN91C96_USE_32_BIT
848 Define this to enable 32 bit addressing
850 CONFIG_DRIVER_SMC91111
851 Support for SMSC's LAN91C111 chip
854 Define this to hold the physical address
855 of the device (I/O space)
857 CONFIG_SMC_USE_32_BIT
858 Define this if data bus is 32 bits
860 CONFIG_SMC_USE_IOFUNCS
861 Define this to use i/o functions instead of macros
862 (some hardware wont work with macros)
865 At the moment only the UHCI host controller is
866 supported (PIP405, MIP405, MPC5200); define
867 CONFIG_USB_UHCI to enable it.
868 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
869 and define CONFIG_USB_STORAGE to enable the USB
872 Supported are USB Keyboards and USB Floppy drives
874 MPC5200 USB requires additional defines:
876 for 528 MHz Clock: 0x0001bbbb
878 for differential drivers: 0x00001000
879 for single ended drivers: 0x00005000
883 The MMC controller on the Intel PXA is supported. To
884 enable this define CONFIG_MMC. The MMC can be
885 accessed from the boot prompt by mapping the device
886 to physical memory similar to flash. Command line is
887 enabled with CFG_CMD_MMC. The MMC driver also works with
888 the FAT fs. This is enabled with CFG_CMD_FAT.
890 - Journaling Flash filesystem support:
891 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
892 CONFIG_JFFS2_NAND_DEV
893 Define these for a default partition on a NAND device
895 CFG_JFFS2_FIRST_SECTOR,
896 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
897 Define these for a default partition on a NOR device
900 Define this to create an own partition. You have to provide a
901 function struct part_info* jffs2_part_info(int part_num)
903 If you define only one JFFS2 partition you may also want to
904 #define CFG_JFFS_SINGLE_PART 1
905 to disable the command chpart. This is the default when you
906 have not defined a custom partition
911 Define this to enable standard (PC-Style) keyboard
915 Standard PC keyboard driver with US (is default) and
916 GERMAN key layout (switch via environment 'keymap=de') support.
917 Export function i8042_kbd_init, i8042_tstc and i8042_getc
918 for cfb_console. Supports cursor blinking.
923 Define this to enable video support (for output to
928 Enable Chips & Technologies 69000 Video chip
930 CONFIG_VIDEO_SMI_LYNXEM
931 Enable Silicon Motion SMI 712/710/810 Video chip. The
932 video output is selected via environment 'videoout'
933 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
936 For the CT69000 and SMI_LYNXEM drivers, videomode is
937 selected via environment 'videomode'. Two diferent ways
939 - "videomode=num" 'num' is a standard LiLo mode numbers.
940 Following standard modes are supported (* is default):
942 Colors 640x480 800x600 1024x768 1152x864 1280x1024
943 -------------+---------------------------------------------
944 8 bits | 0x301* 0x303 0x305 0x161 0x307
945 15 bits | 0x310 0x313 0x316 0x162 0x319
946 16 bits | 0x311 0x314 0x317 0x163 0x31A
947 24 bits | 0x312 0x315 0x318 ? 0x31B
948 -------------+---------------------------------------------
949 (i.e. setenv videomode 317; saveenv; reset;)
951 - "videomode=bootargs" all the video parameters are parsed
952 from the bootargs. (See drivers/videomodes.c)
955 CONFIG_VIDEO_SED13806
956 Enable Epson SED13806 driver. This driver supports 8bpp
957 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
958 or CONFIG_VIDEO_SED13806_16BPP
963 Define this to enable a custom keyboard support.
964 This simply calls drv_keyboard_init() which must be
965 defined in your board-specific files.
966 The only board using this so far is RBC823.
968 - LCD Support: CONFIG_LCD
970 Define this to enable LCD support (for output to LCD
971 display); also select one of the supported displays
972 by defining one of these:
974 CONFIG_NEC_NL6448AC33:
976 NEC NL6448AC33-18. Active, color, single scan.
978 CONFIG_NEC_NL6448BC20
980 NEC NL6448BC20-08. 6.5", 640x480.
981 Active, color, single scan.
983 CONFIG_NEC_NL6448BC33_54
985 NEC NL6448BC33-54. 10.4", 640x480.
986 Active, color, single scan.
990 Sharp 320x240. Active, color, single scan.
991 It isn't 16x9, and I am not sure what it is.
993 CONFIG_SHARP_LQ64D341
995 Sharp LQ64D341 display, 640x480.
996 Active, color, single scan.
1000 HLD1045 display, 640x480.
1001 Active, color, single scan.
1005 Optrex CBL50840-2 NF-FW 99 22 M5
1007 Hitachi LMG6912RPFC-00T
1011 320x240. Black & white.
1013 Normally display is black on white background; define
1014 CFG_WHITE_ON_BLACK to get it inverted.
1016 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1018 If this option is set, the environment is checked for
1019 a variable "splashimage". If found, the usual display
1020 of logo, copyright and system information on the LCD
1021 is suppressed and the BMP image at the address
1022 specified in "splashimage" is loaded instead. The
1023 console is redirected to the "nulldev", too. This
1024 allows for a "silent" boot where a splash screen is
1025 loaded very quickly after power-on.
1027 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1029 If this option is set, additionally to standard BMP
1030 images, gzipped BMP images can be displayed via the
1031 splashscreen support or the bmp command.
1033 - Compression support:
1036 If this option is set, support for bzip2 compressed
1037 images is included. If not, only uncompressed and gzip
1038 compressed images are supported.
1040 NOTE: the bzip2 algorithm requires a lot of RAM, so
1041 the malloc area (as defined by CFG_MALLOC_LEN) should
1047 The address of PHY on MII bus.
1049 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1051 The clock frequency of the MII bus
1055 If this option is set, support for speed/duplex
1056 detection of Gigabit PHY is included.
1058 CONFIG_PHY_RESET_DELAY
1060 Some PHY like Intel LXT971A need extra delay after
1061 reset before any MII register access is possible.
1062 For such PHY, set this option to the usec delay
1063 required. (minimum 300usec for LXT971A)
1065 CONFIG_PHY_CMD_DELAY (ppc4xx)
1067 Some PHY like Intel LXT971A need extra delay after
1068 command issued before MII status register can be read
1075 Define a default value for ethernet address to use
1076 for the respective ethernet interface, in case this
1077 is not determined automatically.
1082 Define a default value for the IP address to use for
1083 the default ethernet interface, in case this is not
1084 determined through e.g. bootp.
1086 - Server IP address:
1089 Defines a default value for theIP address of a TFTP
1090 server to contact when using the "tftboot" command.
1092 - BOOTP Recovery Mode:
1093 CONFIG_BOOTP_RANDOM_DELAY
1095 If you have many targets in a network that try to
1096 boot using BOOTP, you may want to avoid that all
1097 systems send out BOOTP requests at precisely the same
1098 moment (which would happen for instance at recovery
1099 from a power failure, when all systems will try to
1100 boot, thus flooding the BOOTP server. Defining
1101 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1102 inserted before sending out BOOTP requests. The
1103 following delays are insterted then:
1105 1st BOOTP request: delay 0 ... 1 sec
1106 2nd BOOTP request: delay 0 ... 2 sec
1107 3rd BOOTP request: delay 0 ... 4 sec
1109 BOOTP requests: delay 0 ... 8 sec
1111 - DHCP Advanced Options:
1114 You can fine tune the DHCP functionality by adding
1115 these flags to the CONFIG_BOOTP_MASK define:
1117 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1118 serverip from a DHCP server, it is possible that more
1119 than one DNS serverip is offered to the client.
1120 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1121 serverip will be stored in the additional environment
1122 variable "dnsip2". The first DNS serverip is always
1123 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1124 is added to the CONFIG_BOOTP_MASK.
1126 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1127 to do a dynamic update of a DNS server. To do this, they
1128 need the hostname of the DHCP requester.
1129 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1130 CONFIG_BOOTP_MASK, the content of the "hostname"
1131 environment variable is passed as option 12 to
1135 CONFIG_CDP_DEVICE_ID
1137 The device id used in CDP trigger frames.
1139 CONFIG_CDP_DEVICE_ID_PREFIX
1141 A two character string which is prefixed to the MAC address
1146 A printf format string which contains the ascii name of
1147 the port. Normally is set to "eth%d" which sets
1148 eth0 for the first ethernet, eth1 for the second etc.
1150 CONFIG_CDP_CAPABILITIES
1152 A 32bit integer which indicates the device capabilities;
1153 0x00000010 for a normal host which does not forwards.
1157 An ascii string containing the version of the software.
1161 An ascii string containing the name of the platform.
1165 A 32bit integer sent on the trigger.
1167 CONFIG_CDP_POWER_CONSUMPTION
1169 A 16bit integer containing the power consumption of the
1170 device in .1 of milliwatts.
1172 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1174 A byte containing the id of the VLAN.
1176 - Status LED: CONFIG_STATUS_LED
1178 Several configurations allow to display the current
1179 status using a LED. For instance, the LED will blink
1180 fast while running U-Boot code, stop blinking as
1181 soon as a reply to a BOOTP request was received, and
1182 start blinking slow once the Linux kernel is running
1183 (supported by a status LED driver in the Linux
1184 kernel). Defining CONFIG_STATUS_LED enables this
1187 - CAN Support: CONFIG_CAN_DRIVER
1189 Defining CONFIG_CAN_DRIVER enables CAN driver support
1190 on those systems that support this (optional)
1191 feature, like the TQM8xxL modules.
1193 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1195 These enable I2C serial bus commands. Defining either of
1196 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1197 include the appropriate I2C driver for the selected cpu.
1199 This will allow you to use i2c commands at the u-boot
1200 command line (as long as you set CFG_CMD_I2C in
1201 CONFIG_COMMANDS) and communicate with i2c based realtime
1202 clock chips. See common/cmd_i2c.c for a description of the
1203 command line interface.
1205 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1207 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1208 bit-banging) driver instead of CPM or similar hardware
1211 There are several other quantities that must also be
1212 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1214 In both cases you will need to define CFG_I2C_SPEED
1215 to be the frequency (in Hz) at which you wish your i2c bus
1216 to run and CFG_I2C_SLAVE to be the address of this node (ie
1217 the cpu's i2c node address).
1219 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1220 sets the cpu up as a master node and so its address should
1221 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1222 p.16-473). So, set CFG_I2C_SLAVE to 0.
1224 That's all that's required for CONFIG_HARD_I2C.
1226 If you use the software i2c interface (CONFIG_SOFT_I2C)
1227 then the following macros need to be defined (examples are
1228 from include/configs/lwmon.h):
1232 (Optional). Any commands necessary to enable the I2C
1233 controller or configure ports.
1235 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1239 (Only for MPC8260 CPU). The I/O port to use (the code
1240 assumes both bits are on the same port). Valid values
1241 are 0..3 for ports A..D.
1245 The code necessary to make the I2C data line active
1246 (driven). If the data line is open collector, this
1249 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1253 The code necessary to make the I2C data line tri-stated
1254 (inactive). If the data line is open collector, this
1257 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1261 Code that returns TRUE if the I2C data line is high,
1264 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1268 If <bit> is TRUE, sets the I2C data line high. If it
1269 is FALSE, it clears it (low).
1271 eg: #define I2C_SDA(bit) \
1272 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1273 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1277 If <bit> is TRUE, sets the I2C clock line high. If it
1278 is FALSE, it clears it (low).
1280 eg: #define I2C_SCL(bit) \
1281 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1282 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1286 This delay is invoked four times per clock cycle so this
1287 controls the rate of data transfer. The data rate thus
1288 is 1 / (I2C_DELAY * 4). Often defined to be something
1291 #define I2C_DELAY udelay(2)
1295 When a board is reset during an i2c bus transfer
1296 chips might think that the current transfer is still
1297 in progress. On some boards it is possible to access
1298 the i2c SCLK line directly, either by using the
1299 processor pin as a GPIO or by having a second pin
1300 connected to the bus. If this option is defined a
1301 custom i2c_init_board() routine in boards/xxx/board.c
1302 is run early in the boot sequence.
1304 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1306 This option enables configuration of bi_iic_fast[] flags
1307 in u-boot bd_info structure based on u-boot environment
1308 variable "i2cfast". (see also i2cfast)
1310 - SPI Support: CONFIG_SPI
1312 Enables SPI driver (so far only tested with
1313 SPI EEPROM, also an instance works with Crystal A/D and
1314 D/As on the SACSng board)
1318 Enables extended (16-bit) SPI EEPROM addressing.
1319 (symmetrical to CONFIG_I2C_X)
1323 Enables a software (bit-bang) SPI driver rather than
1324 using hardware support. This is a general purpose
1325 driver that only requires three general I/O port pins
1326 (two outputs, one input) to function. If this is
1327 defined, the board configuration must define several
1328 SPI configuration items (port pins to use, etc). For
1329 an example, see include/configs/sacsng.h.
1331 - FPGA Support: CONFIG_FPGA_COUNT
1333 Specify the number of FPGA devices to support.
1337 Used to specify the types of FPGA devices. For example,
1338 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1340 CFG_FPGA_PROG_FEEDBACK
1342 Enable printing of hash marks during FPGA configuration.
1346 Enable checks on FPGA configuration interface busy
1347 status by the configuration function. This option
1348 will require a board or device specific function to
1353 If defined, a function that provides delays in the FPGA
1354 configuration driver.
1356 CFG_FPGA_CHECK_CTRLC
1357 Allow Control-C to interrupt FPGA configuration
1359 CFG_FPGA_CHECK_ERROR
1361 Check for configuration errors during FPGA bitfile
1362 loading. For example, abort during Virtex II
1363 configuration if the INIT_B line goes low (which
1364 indicated a CRC error).
1368 Maximum time to wait for the INIT_B line to deassert
1369 after PROB_B has been deasserted during a Virtex II
1370 FPGA configuration sequence. The default time is 500
1375 Maximum time to wait for BUSY to deassert during
1376 Virtex II FPGA configuration. The default is 5 mS.
1378 CFG_FPGA_WAIT_CONFIG
1380 Time to wait after FPGA configuration. The default is
1383 - Configuration Management:
1386 If defined, this string will be added to the U-Boot
1387 version information (U_BOOT_VERSION)
1389 - Vendor Parameter Protection:
1391 U-Boot considers the values of the environment
1392 variables "serial#" (Board Serial Number) and
1393 "ethaddr" (Ethernet Address) to be parameters that
1394 are set once by the board vendor / manufacturer, and
1395 protects these variables from casual modification by
1396 the user. Once set, these variables are read-only,
1397 and write or delete attempts are rejected. You can
1398 change this behviour:
1400 If CONFIG_ENV_OVERWRITE is #defined in your config
1401 file, the write protection for vendor parameters is
1402 completely disabled. Anybody can change or delete
1405 Alternatively, if you #define _both_ CONFIG_ETHADDR
1406 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1407 ethernet address is installed in the environment,
1408 which can be changed exactly ONCE by the user. [The
1409 serial# is unaffected by this, i. e. it remains
1415 Define this variable to enable the reservation of
1416 "protected RAM", i. e. RAM which is not overwritten
1417 by U-Boot. Define CONFIG_PRAM to hold the number of
1418 kB you want to reserve for pRAM. You can overwrite
1419 this default value by defining an environment
1420 variable "pram" to the number of kB you want to
1421 reserve. Note that the board info structure will
1422 still show the full amount of RAM. If pRAM is
1423 reserved, a new environment variable "mem" will
1424 automatically be defined to hold the amount of
1425 remaining RAM in a form that can be passed as boot
1426 argument to Linux, for instance like that:
1428 setenv bootargs ... mem=\${mem}
1431 This way you can tell Linux not to use this memory,
1432 either, which results in a memory region that will
1433 not be affected by reboots.
1435 *WARNING* If your board configuration uses automatic
1436 detection of the RAM size, you must make sure that
1437 this memory test is non-destructive. So far, the
1438 following board configurations are known to be
1441 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1442 HERMES, IP860, RPXlite, LWMON, LANTEC,
1443 PCU_E, FLAGADM, TQM8260
1448 Define this variable to stop the system in case of a
1449 fatal error, so that you have to reset it manually.
1450 This is probably NOT a good idea for an embedded
1451 system where you want to system to reboot
1452 automatically as fast as possible, but it may be
1453 useful during development since you can try to debug
1454 the conditions that lead to the situation.
1456 CONFIG_NET_RETRY_COUNT
1458 This variable defines the number of retries for
1459 network operations like ARP, RARP, TFTP, or BOOTP
1460 before giving up the operation. If not defined, a
1461 default value of 5 is used.
1463 - Command Interpreter:
1466 Enable auto completion of commands using TAB.
1470 Define this variable to enable the "hush" shell (from
1471 Busybox) as command line interpreter, thus enabling
1472 powerful command line syntax like
1473 if...then...else...fi conditionals or `&&' and '||'
1474 constructs ("shell scripts").
1476 If undefined, you get the old, much simpler behaviour
1477 with a somewhat smaller memory footprint.
1482 This defines the secondary prompt string, which is
1483 printed when the command interpreter needs more input
1484 to complete a command. Usually "> ".
1488 In the current implementation, the local variables
1489 space and global environment variables space are
1490 separated. Local variables are those you define by
1491 simply typing `name=value'. To access a local
1492 variable later on, you have write `$name' or
1493 `${name}'; to execute the contents of a variable
1494 directly type `$name' at the command prompt.
1496 Global environment variables are those you use
1497 setenv/printenv to work with. To run a command stored
1498 in such a variable, you need to use the run command,
1499 and you must not use the '$' sign to access them.
1501 To store commands and special characters in a
1502 variable, please use double quotation marks
1503 surrounding the whole text of the variable, instead
1504 of the backslashes before semicolons and special
1507 - Commandline Editing and History:
1508 CONFIG_CMDLINE_EDITING
1510 Enable editiong and History functions for interactive
1511 commandline input operations
1513 - Default Environment:
1514 CONFIG_EXTRA_ENV_SETTINGS
1516 Define this to contain any number of null terminated
1517 strings (variable = value pairs) that will be part of
1518 the default environment compiled into the boot image.
1520 For example, place something like this in your
1521 board's config file:
1523 #define CONFIG_EXTRA_ENV_SETTINGS \
1527 Warning: This method is based on knowledge about the
1528 internal format how the environment is stored by the
1529 U-Boot code. This is NOT an official, exported
1530 interface! Although it is unlikely that this format
1531 will change soon, there is no guarantee either.
1532 You better know what you are doing here.
1534 Note: overly (ab)use of the default environment is
1535 discouraged. Make sure to check other ways to preset
1536 the environment like the autoscript function or the
1539 - DataFlash Support:
1540 CONFIG_HAS_DATAFLASH
1542 Defining this option enables DataFlash features and
1543 allows to read/write in Dataflash via the standard
1546 - SystemACE Support:
1549 Adding this option adds support for Xilinx SystemACE
1550 chips attached via some sort of local bus. The address
1551 of the chip must alsh be defined in the
1552 CFG_SYSTEMACE_BASE macro. For example:
1554 #define CONFIG_SYSTEMACE
1555 #define CFG_SYSTEMACE_BASE 0xf0000000
1557 When SystemACE support is added, the "ace" device type
1558 becomes available to the fat commands, i.e. fatls.
1560 - TFTP Fixed UDP Port:
1563 If this is defined, the environment variable tftpsrcp
1564 is used to supply the TFTP UDP source port value.
1565 If tftpsrcp isn't defined, the normal pseudo-random port
1566 number generator is used.
1568 Also, the environment variable tftpdstp is used to supply
1569 the TFTP UDP destination port value. If tftpdstp isn't
1570 defined, the normal port 69 is used.
1572 The purpose for tftpsrcp is to allow a TFTP server to
1573 blindly start the TFTP transfer using the pre-configured
1574 target IP address and UDP port. This has the effect of
1575 "punching through" the (Windows XP) firewall, allowing
1576 the remainder of the TFTP transfer to proceed normally.
1577 A better solution is to properly configure the firewall,
1578 but sometimes that is not allowed.
1580 - Show boot progress:
1581 CONFIG_SHOW_BOOT_PROGRESS
1583 Defining this option allows to add some board-
1584 specific code (calling a user-provided function
1585 "show_boot_progress(int)") that enables you to show
1586 the system's boot progress on some display (for
1587 example, some LED's) on your board. At the moment,
1588 the following checkpoints are implemented:
1591 1 common/cmd_bootm.c before attempting to boot an image
1592 -1 common/cmd_bootm.c Image header has bad magic number
1593 2 common/cmd_bootm.c Image header has correct magic number
1594 -2 common/cmd_bootm.c Image header has bad checksum
1595 3 common/cmd_bootm.c Image header has correct checksum
1596 -3 common/cmd_bootm.c Image data has bad checksum
1597 4 common/cmd_bootm.c Image data has correct checksum
1598 -4 common/cmd_bootm.c Image is for unsupported architecture
1599 5 common/cmd_bootm.c Architecture check OK
1600 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1601 6 common/cmd_bootm.c Image Type check OK
1602 -6 common/cmd_bootm.c gunzip uncompression error
1603 -7 common/cmd_bootm.c Unimplemented compression type
1604 7 common/cmd_bootm.c Uncompression OK
1605 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1606 8 common/cmd_bootm.c Image Type check OK
1607 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1608 9 common/cmd_bootm.c Start initial ramdisk verification
1609 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1610 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1611 10 common/cmd_bootm.c Ramdisk header is OK
1612 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1613 11 common/cmd_bootm.c Ramdisk data has correct checksum
1614 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1615 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1616 13 common/cmd_bootm.c Start multifile image verification
1617 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1618 15 common/cmd_bootm.c All preparation done, transferring control to OS
1620 -30 lib_ppc/board.c Fatal error, hang the system
1621 -31 post/post.c POST test failed, detected by post_output_backlog()
1622 -32 post/post.c POST test failed, detected by post_run_single()
1624 -1 common/cmd_doc.c Bad usage of "doc" command
1625 -1 common/cmd_doc.c No boot device
1626 -1 common/cmd_doc.c Unknown Chip ID on boot device
1627 -1 common/cmd_doc.c Read Error on boot device
1628 -1 common/cmd_doc.c Image header has bad magic number
1630 -1 common/cmd_ide.c Bad usage of "ide" command
1631 -1 common/cmd_ide.c No boot device
1632 -1 common/cmd_ide.c Unknown boot device
1633 -1 common/cmd_ide.c Unknown partition table
1634 -1 common/cmd_ide.c Invalid partition type
1635 -1 common/cmd_ide.c Read Error on boot device
1636 -1 common/cmd_ide.c Image header has bad magic number
1638 -1 common/cmd_nand.c Bad usage of "nand" command
1639 -1 common/cmd_nand.c No boot device
1640 -1 common/cmd_nand.c Unknown Chip ID on boot device
1641 -1 common/cmd_nand.c Read Error on boot device
1642 -1 common/cmd_nand.c Image header has bad magic number
1644 -1 common/env_common.c Environment has a bad CRC, using default
1650 [so far only for SMDK2400 and TRAB boards]
1652 - Modem support endable:
1653 CONFIG_MODEM_SUPPORT
1655 - RTS/CTS Flow control enable:
1658 - Modem debug support:
1659 CONFIG_MODEM_SUPPORT_DEBUG
1661 Enables debugging stuff (char screen[1024], dbg())
1662 for modem support. Useful only with BDI2000.
1664 - Interrupt support (PPC):
1666 There are common interrupt_init() and timer_interrupt()
1667 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1668 for cpu specific initialization. interrupt_init_cpu()
1669 should set decrementer_count to appropriate value. If
1670 cpu resets decrementer automatically after interrupt
1671 (ppc4xx) it should set decrementer_count to zero.
1672 timer_interrupt() calls timer_interrupt_cpu() for cpu
1673 specific handling. If board has watchdog / status_led
1674 / other_activity_monitor it works automatically from
1675 general timer_interrupt().
1679 In the target system modem support is enabled when a
1680 specific key (key combination) is pressed during
1681 power-on. Otherwise U-Boot will boot normally
1682 (autoboot). The key_pressed() fuction is called from
1683 board_init(). Currently key_pressed() is a dummy
1684 function, returning 1 and thus enabling modem
1687 If there are no modem init strings in the
1688 environment, U-Boot proceed to autoboot; the
1689 previous output (banner, info printfs) will be
1692 See also: doc/README.Modem
1695 Configuration Settings:
1696 -----------------------
1698 - CFG_LONGHELP: Defined when you want long help messages included;
1699 undefine this when you're short of memory.
1701 - CFG_PROMPT: This is what U-Boot prints on the console to
1702 prompt for user input.
1704 - CFG_CBSIZE: Buffer size for input from the Console
1706 - CFG_PBSIZE: Buffer size for Console output
1708 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1710 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1711 the application (usually a Linux kernel) when it is
1714 - CFG_BAUDRATE_TABLE:
1715 List of legal baudrate settings for this board.
1717 - CFG_CONSOLE_INFO_QUIET
1718 Suppress display of console information at boot.
1720 - CFG_CONSOLE_IS_IN_ENV
1721 If the board specific function
1722 extern int overwrite_console (void);
1723 returns 1, the stdin, stderr and stdout are switched to the
1724 serial port, else the settings in the environment are used.
1726 - CFG_CONSOLE_OVERWRITE_ROUTINE
1727 Enable the call to overwrite_console().
1729 - CFG_CONSOLE_ENV_OVERWRITE
1730 Enable overwrite of previous console environment settings.
1732 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1733 Begin and End addresses of the area used by the
1737 Enable an alternate, more extensive memory test.
1739 - CFG_MEMTEST_SCRATCH:
1740 Scratch address used by the alternate memory test
1741 You only need to set this if address zero isn't writeable
1743 - CFG_TFTP_LOADADDR:
1744 Default load address for network file downloads
1746 - CFG_LOADS_BAUD_CHANGE:
1747 Enable temporary baudrate change while serial download
1750 Physical start address of SDRAM. _Must_ be 0 here.
1753 Physical start address of Motherboard I/O (if using a
1757 Physical start address of Flash memory.
1760 Physical start address of boot monitor code (set by
1761 make config files to be same as the text base address
1762 (TEXT_BASE) used when linking) - same as
1763 CFG_FLASH_BASE when booting from flash.
1766 Size of memory reserved for monitor code, used to
1767 determine _at_compile_time_ (!) if the environment is
1768 embedded within the U-Boot image, or in a separate
1772 Size of DRAM reserved for malloc() use.
1775 Normally compressed uImages are limited to an
1776 uncompressed size of 8 MBytes. If this is not enough,
1777 you can define CFG_BOOTM_LEN in your board config file
1778 to adjust this setting to your needs.
1781 Maximum size of memory mapped by the startup code of
1782 the Linux kernel; all data that must be processed by
1783 the Linux kernel (bd_info, boot arguments, eventually
1784 initrd image) must be put below this limit.
1786 - CFG_MAX_FLASH_BANKS:
1787 Max number of Flash memory banks
1789 - CFG_MAX_FLASH_SECT:
1790 Max number of sectors on a Flash chip
1792 - CFG_FLASH_ERASE_TOUT:
1793 Timeout for Flash erase operations (in ms)
1795 - CFG_FLASH_WRITE_TOUT:
1796 Timeout for Flash write operations (in ms)
1798 - CFG_FLASH_LOCK_TOUT
1799 Timeout for Flash set sector lock bit operation (in ms)
1801 - CFG_FLASH_UNLOCK_TOUT
1802 Timeout for Flash clear lock bits operation (in ms)
1804 - CFG_FLASH_PROTECTION
1805 If defined, hardware flash sectors protection is used
1806 instead of U-Boot software protection.
1808 - CFG_DIRECT_FLASH_TFTP:
1810 Enable TFTP transfers directly to flash memory;
1811 without this option such a download has to be
1812 performed in two steps: (1) download to RAM, and (2)
1813 copy from RAM to flash.
1815 The two-step approach is usually more reliable, since
1816 you can check if the download worked before you erase
1817 the flash, but in some situations (when sytem RAM is
1818 too limited to allow for a tempory copy of the
1819 downloaded image) this option may be very useful.
1822 Define if the flash driver uses extra elements in the
1823 common flash structure for storing flash geometry.
1825 - CFG_FLASH_CFI_DRIVER
1826 This option also enables the building of the cfi_flash driver
1827 in the drivers directory
1829 - CFG_FLASH_QUIET_TEST
1830 If this option is defined, the common CFI flash doesn't
1831 print it's warning upon not recognized FLASH banks. This
1832 is useful, if some of the configured banks are only
1833 optionally available.
1835 - CFG_RX_ETH_BUFFER:
1836 Defines the number of ethernet receive buffers. On some
1837 ethernet controllers it is recommended to set this value
1838 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1839 buffers can be full shortly after enabling the interface
1840 on high ethernet traffic.
1841 Defaults to 4 if not defined.
1843 The following definitions that deal with the placement and management
1844 of environment data (variable area); in general, we support the
1845 following configurations:
1847 - CFG_ENV_IS_IN_FLASH:
1849 Define this if the environment is in flash memory.
1851 a) The environment occupies one whole flash sector, which is
1852 "embedded" in the text segment with the U-Boot code. This
1853 happens usually with "bottom boot sector" or "top boot
1854 sector" type flash chips, which have several smaller
1855 sectors at the start or the end. For instance, such a
1856 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1857 such a case you would place the environment in one of the
1858 4 kB sectors - with U-Boot code before and after it. With
1859 "top boot sector" type flash chips, you would put the
1860 environment in one of the last sectors, leaving a gap
1861 between U-Boot and the environment.
1865 Offset of environment data (variable area) to the
1866 beginning of flash memory; for instance, with bottom boot
1867 type flash chips the second sector can be used: the offset
1868 for this sector is given here.
1870 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1874 This is just another way to specify the start address of
1875 the flash sector containing the environment (instead of
1878 - CFG_ENV_SECT_SIZE:
1880 Size of the sector containing the environment.
1883 b) Sometimes flash chips have few, equal sized, BIG sectors.
1884 In such a case you don't want to spend a whole sector for
1889 If you use this in combination with CFG_ENV_IS_IN_FLASH
1890 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1891 of this flash sector for the environment. This saves
1892 memory for the RAM copy of the environment.
1894 It may also save flash memory if you decide to use this
1895 when your environment is "embedded" within U-Boot code,
1896 since then the remainder of the flash sector could be used
1897 for U-Boot code. It should be pointed out that this is
1898 STRONGLY DISCOURAGED from a robustness point of view:
1899 updating the environment in flash makes it always
1900 necessary to erase the WHOLE sector. If something goes
1901 wrong before the contents has been restored from a copy in
1902 RAM, your target system will be dead.
1904 - CFG_ENV_ADDR_REDUND
1907 These settings describe a second storage area used to hold
1908 a redundand copy of the environment data, so that there is
1909 a valid backup copy in case there is a power failure during
1910 a "saveenv" operation.
1912 BE CAREFUL! Any changes to the flash layout, and some changes to the
1913 source code will make it necessary to adapt <board>/u-boot.lds*
1917 - CFG_ENV_IS_IN_NVRAM:
1919 Define this if you have some non-volatile memory device
1920 (NVRAM, battery buffered SRAM) which you want to use for the
1926 These two #defines are used to determin the memory area you
1927 want to use for environment. It is assumed that this memory
1928 can just be read and written to, without any special
1931 BE CAREFUL! The first access to the environment happens quite early
1932 in U-Boot initalization (when we try to get the setting of for the
1933 console baudrate). You *MUST* have mappend your NVRAM area then, or
1936 Please note that even with NVRAM we still use a copy of the
1937 environment in RAM: we could work on NVRAM directly, but we want to
1938 keep settings there always unmodified except somebody uses "saveenv"
1939 to save the current settings.
1942 - CFG_ENV_IS_IN_EEPROM:
1944 Use this if you have an EEPROM or similar serial access
1945 device and a driver for it.
1950 These two #defines specify the offset and size of the
1951 environment area within the total memory of your EEPROM.
1953 - CFG_I2C_EEPROM_ADDR:
1954 If defined, specified the chip address of the EEPROM device.
1955 The default address is zero.
1957 - CFG_EEPROM_PAGE_WRITE_BITS:
1958 If defined, the number of bits used to address bytes in a
1959 single page in the EEPROM device. A 64 byte page, for example
1960 would require six bits.
1962 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1963 If defined, the number of milliseconds to delay between
1964 page writes. The default is zero milliseconds.
1966 - CFG_I2C_EEPROM_ADDR_LEN:
1967 The length in bytes of the EEPROM memory array address. Note
1968 that this is NOT the chip address length!
1970 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1971 EEPROM chips that implement "address overflow" are ones
1972 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1973 address and the extra bits end up in the "chip address" bit
1974 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1977 Note that we consider the length of the address field to
1978 still be one byte because the extra address bits are hidden
1979 in the chip address.
1982 The size in bytes of the EEPROM device.
1985 - CFG_ENV_IS_IN_DATAFLASH:
1987 Define this if you have a DataFlash memory device which you
1988 want to use for the environment.
1994 These three #defines specify the offset and size of the
1995 environment area within the total memory of your DataFlash placed
1996 at the specified address.
1998 - CFG_ENV_IS_IN_NAND:
2000 Define this if you have a NAND device which you want to use
2001 for the environment.
2006 These two #defines specify the offset and size of the environment
2007 area within the first NAND device.
2009 - CFG_ENV_OFFSET_REDUND
2011 This setting describes a second storage area of CFG_ENV_SIZE
2012 size used to hold a redundant copy of the environment data,
2013 so that there is a valid backup copy in case there is a
2014 power failure during a "saveenv" operation.
2016 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned
2017 to a block boundary, and CFG_ENV_SIZE must be a multiple of
2018 the NAND devices block size.
2020 - CFG_SPI_INIT_OFFSET
2022 Defines offset to the initial SPI buffer area in DPRAM. The
2023 area is used at an early stage (ROM part) if the environment
2024 is configured to reside in the SPI EEPROM: We need a 520 byte
2025 scratch DPRAM area. It is used between the two initialization
2026 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2027 to be a good choice since it makes it far enough from the
2028 start of the data area as well as from the stack pointer.
2030 Please note that the environment is read-only as long as the monitor
2031 has been relocated to RAM and a RAM copy of the environment has been
2032 created; also, when using EEPROM you will have to use getenv_r()
2033 until then to read environment variables.
2035 The environment is protected by a CRC32 checksum. Before the monitor
2036 is relocated into RAM, as a result of a bad CRC you will be working
2037 with the compiled-in default environment - *silently*!!! [This is
2038 necessary, because the first environment variable we need is the
2039 "baudrate" setting for the console - if we have a bad CRC, we don't
2040 have any device yet where we could complain.]
2042 Note: once the monitor has been relocated, then it will complain if
2043 the default environment is used; a new CRC is computed as soon as you
2044 use the "saveenv" command to store a valid environment.
2046 - CFG_FAULT_ECHO_LINK_DOWN:
2047 Echo the inverted Ethernet link state to the fault LED.
2049 Note: If this option is active, then CFG_FAULT_MII_ADDR
2050 also needs to be defined.
2052 - CFG_FAULT_MII_ADDR:
2053 MII address of the PHY to check for the Ethernet link state.
2055 - CFG_64BIT_VSPRINTF:
2056 Makes vsprintf (and all *printf functions) support printing
2057 of 64bit values by using the L quantifier
2059 - CFG_64BIT_STRTOUL:
2060 Adds simple_strtoull that returns a 64bit value
2062 Low Level (hardware related) configuration options:
2063 ---------------------------------------------------
2065 - CFG_CACHELINE_SIZE:
2066 Cache Line Size of the CPU.
2069 Default address of the IMMR after system reset.
2071 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2072 and RPXsuper) to be able to adjust the position of
2073 the IMMR register after a reset.
2075 - Floppy Disk Support:
2076 CFG_FDC_DRIVE_NUMBER
2078 the default drive number (default value 0)
2082 defines the spacing between fdc chipset registers
2087 defines the offset of register from address. It
2088 depends on which part of the data bus is connected to
2089 the fdc chipset. (default value 0)
2091 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
2092 CFG_FDC_DRIVE_NUMBER are undefined, they take their
2095 if CFG_FDC_HW_INIT is defined, then the function
2096 fdc_hw_init() is called at the beginning of the FDC
2097 setup. fdc_hw_init() must be provided by the board
2098 source code. It is used to make hardware dependant
2101 - CFG_IMMR: Physical address of the Internal Memory.
2102 DO NOT CHANGE unless you know exactly what you're
2103 doing! (11-4) [MPC8xx/82xx systems only]
2105 - CFG_INIT_RAM_ADDR:
2107 Start address of memory area that can be used for
2108 initial data and stack; please note that this must be
2109 writable memory that is working WITHOUT special
2110 initialization, i. e. you CANNOT use normal RAM which
2111 will become available only after programming the
2112 memory controller and running certain initialization
2115 U-Boot uses the following memory types:
2116 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2117 - MPC824X: data cache
2118 - PPC4xx: data cache
2120 - CFG_GBL_DATA_OFFSET:
2122 Offset of the initial data structure in the memory
2123 area defined by CFG_INIT_RAM_ADDR. Usually
2124 CFG_GBL_DATA_OFFSET is chosen such that the initial
2125 data is located at the end of the available space
2126 (sometimes written as (CFG_INIT_RAM_END -
2127 CFG_INIT_DATA_SIZE), and the initial stack is just
2128 below that area (growing from (CFG_INIT_RAM_ADDR +
2129 CFG_GBL_DATA_OFFSET) downward.
2132 On the MPC824X (or other systems that use the data
2133 cache for initial memory) the address chosen for
2134 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2135 point to an otherwise UNUSED address space between
2136 the top of RAM and the start of the PCI space.
2138 - CFG_SIUMCR: SIU Module Configuration (11-6)
2140 - CFG_SYPCR: System Protection Control (11-9)
2142 - CFG_TBSCR: Time Base Status and Control (11-26)
2144 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2146 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2148 - CFG_SCCR: System Clock and reset Control Register (15-27)
2150 - CFG_OR_TIMING_SDRAM:
2154 periodic timer for refresh
2156 - CFG_DER: Debug Event Register (37-47)
2158 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2159 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2160 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2162 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2164 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2165 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2166 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2167 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2169 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2170 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2171 Machine Mode Register and Memory Periodic Timer
2172 Prescaler definitions (SDRAM timing)
2174 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2175 enable I2C microcode relocation patch (MPC8xx);
2176 define relocation offset in DPRAM [DSP2]
2178 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2179 enable SPI microcode relocation patch (MPC8xx);
2180 define relocation offset in DPRAM [SCC4]
2183 Use OSCM clock mode on MBX8xx board. Be careful,
2184 wrong setting might damage your board. Read
2185 doc/README.MBX before setting this variable!
2187 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2188 Offset of the bootmode word in DPRAM used by post
2189 (Power On Self Tests). This definition overrides
2190 #define'd default value in commproc.h resp.
2193 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2194 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2195 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2196 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2197 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2198 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2199 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2200 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2201 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2203 - CONFIG_ETHER_ON_FEC[12]
2204 Define to enable FEC[12] on a 8xx series processor.
2206 - CONFIG_FEC[12]_PHY
2207 Define to the hardcoded PHY address which corresponds
2208 to the given FEC; i. e.
2209 #define CONFIG_FEC1_PHY 4
2210 means that the PHY with address 4 is connected to FEC1
2212 When set to -1, means to probe for first available.
2214 - CONFIG_FEC[12]_PHY_NORXERR
2215 The PHY does not have a RXERR line (RMII only).
2216 (so program the FEC to ignore it).
2219 Enable RMII mode for all FECs.
2220 Note that this is a global option, we can't
2221 have one FEC in standard MII mode and another in RMII mode.
2223 - CONFIG_CRC32_VERIFY
2224 Add a verify option to the crc32 command.
2227 => crc32 -v <address> <count> <crc32>
2229 Where address/count indicate a memory area
2230 and crc32 is the correct crc32 which the
2234 Add the "loopw" memory command. This only takes effect if
2235 the memory commands are activated globally (CFG_CMD_MEM).
2238 Add the "mdc" and "mwc" memory commands. These are cyclic
2243 This command will print 4 bytes (10,11,12,13) each 500 ms.
2245 => mwc.l 100 12345678 10
2246 This command will write 12345678 to address 100 all 10 ms.
2248 This only takes effect if the memory commands are activated
2249 globally (CFG_CMD_MEM).
2251 - CONFIG_SKIP_LOWLEVEL_INIT
2252 - CONFIG_SKIP_RELOCATE_UBOOT
2254 [ARM only] If these variables are defined, then
2255 certain low level initializations (like setting up
2256 the memory controller) are omitted and/or U-Boot does
2257 not relocate itself into RAM.
2258 Normally these variables MUST NOT be defined. The
2259 only exception is when U-Boot is loaded (to RAM) by
2260 some other boot loader or by a debugger which
2261 performs these intializations itself.
2264 Building the Software:
2265 ======================
2267 Building U-Boot has been tested in native PPC environments (on a
2268 PowerBook G3 running LinuxPPC 2000) and in cross environments
2269 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2272 If you are not using a native PPC environment, it is assumed that you
2273 have the GNU cross compiling tools available in your path and named
2274 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2275 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2276 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2279 CROSS_COMPILE = ppc_4xx-
2282 U-Boot is intended to be simple to build. After installing the
2283 sources you must configure U-Boot for one specific board type. This
2288 where "NAME_config" is the name of one of the existing
2289 configurations; the following names are supported:
2291 ADCIOP_config FPS860L_config omap730p2_config
2292 ADS860_config GEN860T_config pcu_e_config
2294 AR405_config GENIETV_config PIP405_config
2295 at91rm9200dk_config GTH_config QS823_config
2296 CANBT_config hermes_config QS850_config
2297 cmi_mpc5xx_config hymod_config QS860T_config
2298 cogent_common_config IP860_config RPXlite_config
2299 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2300 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2301 CPCI405_config JSE_config rsdproto_config
2302 CPCIISER4_config LANTEC_config Sandpoint8240_config
2303 csb272_config lwmon_config sbc8260_config
2304 CU824_config MBX860T_config sbc8560_33_config
2305 DUET_ADS_config MBX_config sbc8560_66_config
2306 EBONY_config MPC8260ADS_config SM850_config
2307 ELPT860_config MPC8540ADS_config SPD823TS_config
2308 ESTEEM192E_config MPC8540EVAL_config stxgp3_config
2309 ETX094_config MPC8560ADS_config SXNI855T_config
2310 FADS823_config NETVIA_config TQM823L_config
2311 FADS850SAR_config omap1510inn_config TQM850L_config
2312 FADS860T_config omap1610h2_config TQM855L_config
2313 FPS850L_config omap1610inn_config TQM860L_config
2314 omap5912osk_config walnut_config
2315 omap2420h4_config Yukon8220_config
2318 Note: for some board special configuration names may exist; check if
2319 additional information is available from the board vendor; for
2320 instance, the TQM823L systems are available without (standard)
2321 or with LCD support. You can select such additional "features"
2322 when chosing the configuration, i. e.
2325 - will configure for a plain TQM823L, i. e. no LCD support
2327 make TQM823L_LCD_config
2328 - will configure for a TQM823L with U-Boot console on LCD
2333 Finally, type "make all", and you should get some working U-Boot
2334 images ready for download to / installation on your system:
2336 - "u-boot.bin" is a raw binary image
2337 - "u-boot" is an image in ELF binary format
2338 - "u-boot.srec" is in Motorola S-Record format
2340 By default the build is performed locally and the objects are saved
2341 in the source directory. One of the two methods can be used to change
2342 this behavior and build U-Boot to some external directory:
2344 1. Add O= to the make command line invocations:
2346 make O=/tmp/build distclean
2347 make O=/tmp/build NAME_config
2348 make O=/tmp/build all
2350 2. Set environment variable BUILD_DIR to point to the desired location:
2352 export BUILD_DIR=/tmp/build
2357 Note that the command line "O=" setting overrides the BUILD_DIR environment
2361 Please be aware that the Makefiles assume you are using GNU make, so
2362 for instance on NetBSD you might need to use "gmake" instead of
2366 If the system board that you have is not listed, then you will need
2367 to port U-Boot to your hardware platform. To do this, follow these
2370 1. Add a new configuration option for your board to the toplevel
2371 "Makefile" and to the "MAKEALL" script, using the existing
2372 entries as examples. Note that here and at many other places
2373 boards and other names are listed in alphabetical sort order. Please
2375 2. Create a new directory to hold your board specific code. Add any
2376 files you need. In your board directory, you will need at least
2377 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2378 3. Create a new configuration file "include/configs/<board>.h" for
2380 3. If you're porting U-Boot to a new CPU, then also create a new
2381 directory to hold your CPU specific code. Add any files you need.
2382 4. Run "make <board>_config" with your new name.
2383 5. Type "make", and you should get a working "u-boot.srec" file
2384 to be installed on your target system.
2385 6. Debug and solve any problems that might arise.
2386 [Of course, this last step is much harder than it sounds.]
2389 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2390 ==============================================================
2392 If you have modified U-Boot sources (for instance added a new board
2393 or support for new devices, a new CPU, etc.) you are expected to
2394 provide feedback to the other developers. The feedback normally takes
2395 the form of a "patch", i. e. a context diff against a certain (latest
2396 official or latest in CVS) version of U-Boot sources.
2398 But before you submit such a patch, please verify that your modifi-
2399 cation did not break existing code. At least make sure that *ALL* of
2400 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2401 just run the "MAKEALL" script, which will configure and build U-Boot
2402 for ALL supported system. Be warned, this will take a while. You can
2403 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2404 environment variable to the script, i. e. to use the cross tools from
2405 MontaVista's Hard Hat Linux you can type
2407 CROSS_COMPILE=ppc_8xx- MAKEALL
2409 or to build on a native PowerPC system you can type
2411 CROSS_COMPILE=' ' MAKEALL
2413 When using the MAKEALL script, the default behaviour is to build U-Boot
2414 in the source directory. This location can be changed by setting the
2415 BUILD_DIR environment variable. Also, for each target built, the MAKEALL
2416 script saves two log files (<target>.ERR and <target>.MAKEALL) in the
2417 <source dir>/LOG directory. This default location can be changed by
2418 setting the MAKEALL_LOGDIR environment variable. For example:
2420 export BUILD_DIR=/tmp/build
2421 export MAKEALL_LOGDIR=/tmp/log
2422 CROSS_COMPILE=ppc_8xx- MAKEALL
2424 With the above settings build objects are saved in the /tmp/build, log
2425 files are saved in the /tmp/log and the source tree remains clean during
2426 the whole build process.
2429 See also "U-Boot Porting Guide" below.
2432 Monitor Commands - Overview:
2433 ============================
2435 go - start application at address 'addr'
2436 run - run commands in an environment variable
2437 bootm - boot application image from memory
2438 bootp - boot image via network using BootP/TFTP protocol
2439 tftpboot- boot image via network using TFTP protocol
2440 and env variables "ipaddr" and "serverip"
2441 (and eventually "gatewayip")
2442 rarpboot- boot image via network using RARP/TFTP protocol
2443 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2444 loads - load S-Record file over serial line
2445 loadb - load binary file over serial line (kermit mode)
2447 mm - memory modify (auto-incrementing)
2448 nm - memory modify (constant address)
2449 mw - memory write (fill)
2451 cmp - memory compare
2452 crc32 - checksum calculation
2453 imd - i2c memory display
2454 imm - i2c memory modify (auto-incrementing)
2455 inm - i2c memory modify (constant address)
2456 imw - i2c memory write (fill)
2457 icrc32 - i2c checksum calculation
2458 iprobe - probe to discover valid I2C chip addresses
2459 iloop - infinite loop on address range
2460 isdram - print SDRAM configuration information
2461 sspi - SPI utility commands
2462 base - print or set address offset
2463 printenv- print environment variables
2464 setenv - set environment variables
2465 saveenv - save environment variables to persistent storage
2466 protect - enable or disable FLASH write protection
2467 erase - erase FLASH memory
2468 flinfo - print FLASH memory information
2469 bdinfo - print Board Info structure
2470 iminfo - print header information for application image
2471 coninfo - print console devices and informations
2472 ide - IDE sub-system
2473 loop - infinite loop on address range
2474 loopw - infinite write loop on address range
2475 mtest - simple RAM test
2476 icache - enable or disable instruction cache
2477 dcache - enable or disable data cache
2478 reset - Perform RESET of the CPU
2479 echo - echo args to console
2480 version - print monitor version
2481 help - print online help
2482 ? - alias for 'help'
2485 Monitor Commands - Detailed Description:
2486 ========================================
2490 For now: just type "help <command>".
2493 Environment Variables:
2494 ======================
2496 U-Boot supports user configuration using Environment Variables which
2497 can be made persistent by saving to Flash memory.
2499 Environment Variables are set using "setenv", printed using
2500 "printenv", and saved to Flash using "saveenv". Using "setenv"
2501 without a value can be used to delete a variable from the
2502 environment. As long as you don't save the environment you are
2503 working with an in-memory copy. In case the Flash area containing the
2504 environment is erased by accident, a default environment is provided.
2506 Some configuration options can be set using Environment Variables:
2508 baudrate - see CONFIG_BAUDRATE
2510 bootdelay - see CONFIG_BOOTDELAY
2512 bootcmd - see CONFIG_BOOTCOMMAND
2514 bootargs - Boot arguments when booting an RTOS image
2516 bootfile - Name of the image to load with TFTP
2518 autoload - if set to "no" (any string beginning with 'n'),
2519 "bootp" will just load perform a lookup of the
2520 configuration from the BOOTP server, but not try to
2521 load any image using TFTP
2523 autostart - if set to "yes", an image loaded using the "bootp",
2524 "rarpboot", "tftpboot" or "diskboot" commands will
2525 be automatically started (by internally calling
2528 If set to "no", a standalone image passed to the
2529 "bootm" command will be copied to the load address
2530 (and eventually uncompressed), but NOT be started.
2531 This can be used to load and uncompress arbitrary
2534 i2cfast - (PPC405GP|PPC405EP only)
2535 if set to 'y' configures Linux I2C driver for fast
2536 mode (400kHZ). This environment variable is used in
2537 initialization code. So, for changes to be effective
2538 it must be saved and board must be reset.
2540 initrd_high - restrict positioning of initrd images:
2541 If this variable is not set, initrd images will be
2542 copied to the highest possible address in RAM; this
2543 is usually what you want since it allows for
2544 maximum initrd size. If for some reason you want to
2545 make sure that the initrd image is loaded below the
2546 CFG_BOOTMAPSZ limit, you can set this environment
2547 variable to a value of "no" or "off" or "0".
2548 Alternatively, you can set it to a maximum upper
2549 address to use (U-Boot will still check that it
2550 does not overwrite the U-Boot stack and data).
2552 For instance, when you have a system with 16 MB
2553 RAM, and want to reserve 4 MB from use by Linux,
2554 you can do this by adding "mem=12M" to the value of
2555 the "bootargs" variable. However, now you must make
2556 sure that the initrd image is placed in the first
2557 12 MB as well - this can be done with
2559 setenv initrd_high 00c00000
2561 If you set initrd_high to 0xFFFFFFFF, this is an
2562 indication to U-Boot that all addresses are legal
2563 for the Linux kernel, including addresses in flash
2564 memory. In this case U-Boot will NOT COPY the
2565 ramdisk at all. This may be useful to reduce the
2566 boot time on your system, but requires that this
2567 feature is supported by your Linux kernel.
2569 ipaddr - IP address; needed for tftpboot command
2571 loadaddr - Default load address for commands like "bootp",
2572 "rarpboot", "tftpboot", "loadb" or "diskboot"
2574 loads_echo - see CONFIG_LOADS_ECHO
2576 serverip - TFTP server IP address; needed for tftpboot command
2578 bootretry - see CONFIG_BOOT_RETRY_TIME
2580 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2582 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2584 ethprime - When CONFIG_NET_MULTI is enabled controls which
2585 interface is used first.
2587 ethact - When CONFIG_NET_MULTI is enabled controls which
2588 interface is currently active. For example you
2589 can do the following
2591 => setenv ethact FEC ETHERNET
2592 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2593 => setenv ethact SCC ETHERNET
2594 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2596 netretry - When set to "no" each network operation will
2597 either succeed or fail without retrying.
2598 When set to "once" the network operation will
2599 fail when all the available network interfaces
2600 are tried once without success.
2601 Useful on scripts which control the retry operation
2604 tftpsrcport - If this is set, the value is used for TFTP's
2607 tftpdstport - If this is set, the value is used for TFTP's UDP
2608 destination port instead of the Well Know Port 69.
2610 vlan - When set to a value < 4095 the traffic over
2611 ethernet is encapsulated/received over 802.1q
2614 The following environment variables may be used and automatically
2615 updated by the network boot commands ("bootp" and "rarpboot"),
2616 depending the information provided by your boot server:
2618 bootfile - see above
2619 dnsip - IP address of your Domain Name Server
2620 dnsip2 - IP address of your secondary Domain Name Server
2621 gatewayip - IP address of the Gateway (Router) to use
2622 hostname - Target hostname
2624 netmask - Subnet Mask
2625 rootpath - Pathname of the root filesystem on the NFS server
2626 serverip - see above
2629 There are two special Environment Variables:
2631 serial# - contains hardware identification information such
2632 as type string and/or serial number
2633 ethaddr - Ethernet address
2635 These variables can be set only once (usually during manufacturing of
2636 the board). U-Boot refuses to delete or overwrite these variables
2637 once they have been set once.
2640 Further special Environment Variables:
2642 ver - Contains the U-Boot version string as printed
2643 with the "version" command. This variable is
2644 readonly (see CONFIG_VERSION_VARIABLE).
2647 Please note that changes to some configuration parameters may take
2648 only effect after the next boot (yes, that's just like Windoze :-).
2651 Command Line Parsing:
2652 =====================
2654 There are two different command line parsers available with U-Boot:
2655 the old "simple" one, and the much more powerful "hush" shell:
2657 Old, simple command line parser:
2658 --------------------------------
2660 - supports environment variables (through setenv / saveenv commands)
2661 - several commands on one line, separated by ';'
2662 - variable substitution using "... ${name} ..." syntax
2663 - special characters ('$', ';') can be escaped by prefixing with '\',
2665 setenv bootcmd bootm \${address}
2666 - You can also escape text by enclosing in single apostrophes, for example:
2667 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2672 - similar to Bourne shell, with control structures like
2673 if...then...else...fi, for...do...done; while...do...done,
2674 until...do...done, ...
2675 - supports environment ("global") variables (through setenv / saveenv
2676 commands) and local shell variables (through standard shell syntax
2677 "name=value"); only environment variables can be used with "run"
2683 (1) If a command line (or an environment variable executed by a "run"
2684 command) contains several commands separated by semicolon, and
2685 one of these commands fails, then the remaining commands will be
2688 (2) If you execute several variables with one call to run (i. e.
2689 calling run with a list af variables as arguments), any failing
2690 command will cause "run" to terminate, i. e. the remaining
2691 variables are not executed.
2693 Note for Redundant Ethernet Interfaces:
2694 =======================================
2696 Some boards come with redundant ethernet interfaces; U-Boot supports
2697 such configurations and is capable of automatic selection of a
2698 "working" interface when needed. MAC assignment works as follows:
2700 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2701 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2702 "eth1addr" (=>eth1), "eth2addr", ...
2704 If the network interface stores some valid MAC address (for instance
2705 in SROM), this is used as default address if there is NO correspon-
2706 ding setting in the environment; if the corresponding environment
2707 variable is set, this overrides the settings in the card; that means:
2709 o If the SROM has a valid MAC address, and there is no address in the
2710 environment, the SROM's address is used.
2712 o If there is no valid address in the SROM, and a definition in the
2713 environment exists, then the value from the environment variable is
2716 o If both the SROM and the environment contain a MAC address, and
2717 both addresses are the same, this MAC address is used.
2719 o If both the SROM and the environment contain a MAC address, and the
2720 addresses differ, the value from the environment is used and a
2723 o If neither SROM nor the environment contain a MAC address, an error
2730 The "boot" commands of this monitor operate on "image" files which
2731 can be basicly anything, preceeded by a special header; see the
2732 definitions in include/image.h for details; basicly, the header
2733 defines the following image properties:
2735 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2736 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2737 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2738 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2739 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
2740 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2741 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
2742 * Compression Type (uncompressed, gzip, bzip2)
2748 The header is marked by a special Magic Number, and both the header
2749 and the data portions of the image are secured against corruption by
2756 Although U-Boot should support any OS or standalone application
2757 easily, the main focus has always been on Linux during the design of
2760 U-Boot includes many features that so far have been part of some
2761 special "boot loader" code within the Linux kernel. Also, any
2762 "initrd" images to be used are no longer part of one big Linux image;
2763 instead, kernel and "initrd" are separate images. This implementation
2764 serves several purposes:
2766 - the same features can be used for other OS or standalone
2767 applications (for instance: using compressed images to reduce the
2768 Flash memory footprint)
2770 - it becomes much easier to port new Linux kernel versions because
2771 lots of low-level, hardware dependent stuff are done by U-Boot
2773 - the same Linux kernel image can now be used with different "initrd"
2774 images; of course this also means that different kernel images can
2775 be run with the same "initrd". This makes testing easier (you don't
2776 have to build a new "zImage.initrd" Linux image when you just
2777 change a file in your "initrd"). Also, a field-upgrade of the
2778 software is easier now.
2784 Porting Linux to U-Boot based systems:
2785 ---------------------------------------
2787 U-Boot cannot save you from doing all the necessary modifications to
2788 configure the Linux device drivers for use with your target hardware
2789 (no, we don't intend to provide a full virtual machine interface to
2792 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2794 Just make sure your machine specific header file (for instance
2795 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2796 Information structure as we define in include/u-boot.h, and make
2797 sure that your definition of IMAP_ADDR uses the same value as your
2798 U-Boot configuration in CFG_IMMR.
2801 Configuring the Linux kernel:
2802 -----------------------------
2804 No specific requirements for U-Boot. Make sure you have some root
2805 device (initial ramdisk, NFS) for your target system.
2808 Building a Linux Image:
2809 -----------------------
2811 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2812 not used. If you use recent kernel source, a new build target
2813 "uImage" will exist which automatically builds an image usable by
2814 U-Boot. Most older kernels also have support for a "pImage" target,
2815 which was introduced for our predecessor project PPCBoot and uses a
2816 100% compatible format.
2825 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2826 encapsulate a compressed Linux kernel image with header information,
2827 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2829 * build a standard "vmlinux" kernel image (in ELF binary format):
2831 * convert the kernel into a raw binary image:
2833 ${CROSS_COMPILE}-objcopy -O binary \
2834 -R .note -R .comment \
2835 -S vmlinux linux.bin
2837 * compress the binary image:
2841 * package compressed binary image for U-Boot:
2843 mkimage -A ppc -O linux -T kernel -C gzip \
2844 -a 0 -e 0 -n "Linux Kernel Image" \
2845 -d linux.bin.gz uImage
2848 The "mkimage" tool can also be used to create ramdisk images for use
2849 with U-Boot, either separated from the Linux kernel image, or
2850 combined into one file. "mkimage" encapsulates the images with a 64
2851 byte header containing information about target architecture,
2852 operating system, image type, compression method, entry points, time
2853 stamp, CRC32 checksums, etc.
2855 "mkimage" can be called in two ways: to verify existing images and
2856 print the header information, or to build new images.
2858 In the first form (with "-l" option) mkimage lists the information
2859 contained in the header of an existing U-Boot image; this includes
2860 checksum verification:
2862 tools/mkimage -l image
2863 -l ==> list image header information
2865 The second form (with "-d" option) is used to build a U-Boot image
2866 from a "data file" which is used as image payload:
2868 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2869 -n name -d data_file image
2870 -A ==> set architecture to 'arch'
2871 -O ==> set operating system to 'os'
2872 -T ==> set image type to 'type'
2873 -C ==> set compression type 'comp'
2874 -a ==> set load address to 'addr' (hex)
2875 -e ==> set entry point to 'ep' (hex)
2876 -n ==> set image name to 'name'
2877 -d ==> use image data from 'datafile'
2879 Right now, all Linux kernels for PowerPC systems use the same load
2880 address (0x00000000), but the entry point address depends on the
2883 - 2.2.x kernels have the entry point at 0x0000000C,
2884 - 2.3.x and later kernels have the entry point at 0x00000000.
2886 So a typical call to build a U-Boot image would read:
2888 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2889 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2890 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2891 > examples/uImage.TQM850L
2892 Image Name: 2.4.4 kernel for TQM850L
2893 Created: Wed Jul 19 02:34:59 2000
2894 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2895 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2896 Load Address: 0x00000000
2897 Entry Point: 0x00000000
2899 To verify the contents of the image (or check for corruption):
2901 -> tools/mkimage -l examples/uImage.TQM850L
2902 Image Name: 2.4.4 kernel for TQM850L
2903 Created: Wed Jul 19 02:34:59 2000
2904 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2905 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2906 Load Address: 0x00000000
2907 Entry Point: 0x00000000
2909 NOTE: for embedded systems where boot time is critical you can trade
2910 speed for memory and install an UNCOMPRESSED image instead: this
2911 needs more space in Flash, but boots much faster since it does not
2912 need to be uncompressed:
2914 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2915 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2916 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2917 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2918 > examples/uImage.TQM850L-uncompressed
2919 Image Name: 2.4.4 kernel for TQM850L
2920 Created: Wed Jul 19 02:34:59 2000
2921 Image Type: PowerPC Linux Kernel Image (uncompressed)
2922 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2923 Load Address: 0x00000000
2924 Entry Point: 0x00000000
2927 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2928 when your kernel is intended to use an initial ramdisk:
2930 -> tools/mkimage -n 'Simple Ramdisk Image' \
2931 > -A ppc -O linux -T ramdisk -C gzip \
2932 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2933 Image Name: Simple Ramdisk Image
2934 Created: Wed Jan 12 14:01:50 2000
2935 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2936 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2937 Load Address: 0x00000000
2938 Entry Point: 0x00000000
2941 Installing a Linux Image:
2942 -------------------------
2944 To downloading a U-Boot image over the serial (console) interface,
2945 you must convert the image to S-Record format:
2947 objcopy -I binary -O srec examples/image examples/image.srec
2949 The 'objcopy' does not understand the information in the U-Boot
2950 image header, so the resulting S-Record file will be relative to
2951 address 0x00000000. To load it to a given address, you need to
2952 specify the target address as 'offset' parameter with the 'loads'
2955 Example: install the image to address 0x40100000 (which on the
2956 TQM8xxL is in the first Flash bank):
2958 => erase 40100000 401FFFFF
2964 ## Ready for S-Record download ...
2965 ~>examples/image.srec
2966 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2968 15989 15990 15991 15992
2969 [file transfer complete]
2971 ## Start Addr = 0x00000000
2974 You can check the success of the download using the 'iminfo' command;
2975 this includes a checksum verification so you can be sure no data
2976 corruption happened:
2980 ## Checking Image at 40100000 ...
2981 Image Name: 2.2.13 for initrd on TQM850L
2982 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2983 Data Size: 335725 Bytes = 327 kB = 0 MB
2984 Load Address: 00000000
2985 Entry Point: 0000000c
2986 Verifying Checksum ... OK
2992 The "bootm" command is used to boot an application that is stored in
2993 memory (RAM or Flash). In case of a Linux kernel image, the contents
2994 of the "bootargs" environment variable is passed to the kernel as
2995 parameters. You can check and modify this variable using the
2996 "printenv" and "setenv" commands:
2999 => printenv bootargs
3000 bootargs=root=/dev/ram
3002 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3004 => printenv bootargs
3005 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3008 ## Booting Linux kernel at 40020000 ...
3009 Image Name: 2.2.13 for NFS on TQM850L
3010 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3011 Data Size: 381681 Bytes = 372 kB = 0 MB
3012 Load Address: 00000000
3013 Entry Point: 0000000c
3014 Verifying Checksum ... OK
3015 Uncompressing Kernel Image ... OK
3016 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
3017 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3018 time_init: decrementer frequency = 187500000/60
3019 Calibrating delay loop... 49.77 BogoMIPS
3020 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3023 If you want to boot a Linux kernel with initial ram disk, you pass
3024 the memory addresses of both the kernel and the initrd image (PPBCOOT
3025 format!) to the "bootm" command:
3027 => imi 40100000 40200000
3029 ## Checking Image at 40100000 ...
3030 Image Name: 2.2.13 for initrd on TQM850L
3031 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3032 Data Size: 335725 Bytes = 327 kB = 0 MB
3033 Load Address: 00000000
3034 Entry Point: 0000000c
3035 Verifying Checksum ... OK
3037 ## Checking Image at 40200000 ...
3038 Image Name: Simple Ramdisk Image
3039 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3040 Data Size: 566530 Bytes = 553 kB = 0 MB
3041 Load Address: 00000000
3042 Entry Point: 00000000
3043 Verifying Checksum ... OK
3045 => bootm 40100000 40200000
3046 ## Booting Linux kernel at 40100000 ...
3047 Image Name: 2.2.13 for initrd on TQM850L
3048 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3049 Data Size: 335725 Bytes = 327 kB = 0 MB
3050 Load Address: 00000000
3051 Entry Point: 0000000c
3052 Verifying Checksum ... OK
3053 Uncompressing Kernel Image ... OK
3054 ## Loading RAMDisk Image at 40200000 ...
3055 Image Name: Simple Ramdisk Image
3056 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3057 Data Size: 566530 Bytes = 553 kB = 0 MB
3058 Load Address: 00000000
3059 Entry Point: 00000000
3060 Verifying Checksum ... OK
3061 Loading Ramdisk ... OK
3062 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
3063 Boot arguments: root=/dev/ram
3064 time_init: decrementer frequency = 187500000/60
3065 Calibrating delay loop... 49.77 BogoMIPS
3067 RAMDISK: Compressed image found at block 0
3068 VFS: Mounted root (ext2 filesystem).
3072 More About U-Boot Image Types:
3073 ------------------------------
3075 U-Boot supports the following image types:
3077 "Standalone Programs" are directly runnable in the environment
3078 provided by U-Boot; it is expected that (if they behave
3079 well) you can continue to work in U-Boot after return from
3080 the Standalone Program.
3081 "OS Kernel Images" are usually images of some Embedded OS which
3082 will take over control completely. Usually these programs
3083 will install their own set of exception handlers, device
3084 drivers, set up the MMU, etc. - this means, that you cannot
3085 expect to re-enter U-Boot except by resetting the CPU.
3086 "RAMDisk Images" are more or less just data blocks, and their
3087 parameters (address, size) are passed to an OS kernel that is
3089 "Multi-File Images" contain several images, typically an OS
3090 (Linux) kernel image and one or more data images like
3091 RAMDisks. This construct is useful for instance when you want
3092 to boot over the network using BOOTP etc., where the boot
3093 server provides just a single image file, but you want to get
3094 for instance an OS kernel and a RAMDisk image.
3096 "Multi-File Images" start with a list of image sizes, each
3097 image size (in bytes) specified by an "uint32_t" in network
3098 byte order. This list is terminated by an "(uint32_t)0".
3099 Immediately after the terminating 0 follow the images, one by
3100 one, all aligned on "uint32_t" boundaries (size rounded up to
3101 a multiple of 4 bytes).
3103 "Firmware Images" are binary images containing firmware (like
3104 U-Boot or FPGA images) which usually will be programmed to
3107 "Script files" are command sequences that will be executed by
3108 U-Boot's command interpreter; this feature is especially
3109 useful when you configure U-Boot to use a real shell (hush)
3110 as command interpreter.
3116 One of the features of U-Boot is that you can dynamically load and
3117 run "standalone" applications, which can use some resources of
3118 U-Boot like console I/O functions or interrupt services.
3120 Two simple examples are included with the sources:
3125 'examples/hello_world.c' contains a small "Hello World" Demo
3126 application; it is automatically compiled when you build U-Boot.
3127 It's configured to run at address 0x00040004, so you can play with it
3131 ## Ready for S-Record download ...
3132 ~>examples/hello_world.srec
3133 1 2 3 4 5 6 7 8 9 10 11 ...
3134 [file transfer complete]
3136 ## Start Addr = 0x00040004
3138 => go 40004 Hello World! This is a test.
3139 ## Starting application at 0x00040004 ...
3150 Hit any key to exit ...
3152 ## Application terminated, rc = 0x0
3154 Another example, which demonstrates how to register a CPM interrupt
3155 handler with the U-Boot code, can be found in 'examples/timer.c'.
3156 Here, a CPM timer is set up to generate an interrupt every second.
3157 The interrupt service routine is trivial, just printing a '.'
3158 character, but this is just a demo program. The application can be
3159 controlled by the following keys:
3161 ? - print current values og the CPM Timer registers
3162 b - enable interrupts and start timer
3163 e - stop timer and disable interrupts
3164 q - quit application
3167 ## Ready for S-Record download ...
3168 ~>examples/timer.srec
3169 1 2 3 4 5 6 7 8 9 10 11 ...
3170 [file transfer complete]
3172 ## Start Addr = 0x00040004
3175 ## Starting application at 0x00040004 ...
3178 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3181 [q, b, e, ?] Set interval 1000000 us
3184 [q, b, e, ?] ........
3185 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3188 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3191 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3194 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3196 [q, b, e, ?] ...Stopping timer
3198 [q, b, e, ?] ## Application terminated, rc = 0x0
3204 Over time, many people have reported problems when trying to use the
3205 "minicom" terminal emulation program for serial download. I (wd)
3206 consider minicom to be broken, and recommend not to use it. Under
3207 Unix, I recommend to use C-Kermit for general purpose use (and
3208 especially for kermit binary protocol download ("loadb" command), and
3209 use "cu" for S-Record download ("loads" command).
3211 Nevertheless, if you absolutely want to use it try adding this
3212 configuration to your "File transfer protocols" section:
3214 Name Program Name U/D FullScr IO-Red. Multi
3215 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3216 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3222 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3223 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3225 Building requires a cross environment; it is known to work on
3226 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3227 need gmake since the Makefiles are not compatible with BSD make).
3228 Note that the cross-powerpc package does not install include files;
3229 attempting to build U-Boot will fail because <machine/ansi.h> is
3230 missing. This file has to be installed and patched manually:
3232 # cd /usr/pkg/cross/powerpc-netbsd/include
3234 # ln -s powerpc machine
3235 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3236 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3238 Native builds *don't* work due to incompatibilities between native
3239 and U-Boot include files.
3241 Booting assumes that (the first part of) the image booted is a
3242 stage-2 loader which in turn loads and then invokes the kernel
3243 proper. Loader sources will eventually appear in the NetBSD source
3244 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3245 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3248 Implementation Internals:
3249 =========================
3251 The following is not intended to be a complete description of every
3252 implementation detail. However, it should help to understand the
3253 inner workings of U-Boot and make it easier to port it to custom
3257 Initial Stack, Global Data:
3258 ---------------------------
3260 The implementation of U-Boot is complicated by the fact that U-Boot
3261 starts running out of ROM (flash memory), usually without access to
3262 system RAM (because the memory controller is not initialized yet).
3263 This means that we don't have writable Data or BSS segments, and BSS
3264 is not initialized as zero. To be able to get a C environment working
3265 at all, we have to allocate at least a minimal stack. Implementation
3266 options for this are defined and restricted by the CPU used: Some CPU
3267 models provide on-chip memory (like the IMMR area on MPC8xx and
3268 MPC826x processors), on others (parts of) the data cache can be
3269 locked as (mis-) used as memory, etc.
3271 Chris Hallinan posted a good summary of these issues to the
3272 u-boot-users mailing list:
3274 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3275 From: "Chris Hallinan" <clh@net1plus.com>
3276 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3279 Correct me if I'm wrong, folks, but the way I understand it
3280 is this: Using DCACHE as initial RAM for Stack, etc, does not
3281 require any physical RAM backing up the cache. The cleverness
3282 is that the cache is being used as a temporary supply of
3283 necessary storage before the SDRAM controller is setup. It's
3284 beyond the scope of this list to expain the details, but you
3285 can see how this works by studying the cache architecture and
3286 operation in the architecture and processor-specific manuals.
3288 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3289 is another option for the system designer to use as an
3290 initial stack/ram area prior to SDRAM being available. Either
3291 option should work for you. Using CS 4 should be fine if your
3292 board designers haven't used it for something that would
3293 cause you grief during the initial boot! It is frequently not
3296 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3297 with your processor/board/system design. The default value
3298 you will find in any recent u-boot distribution in
3299 walnut.h should work for you. I'd set it to a value larger
3300 than your SDRAM module. If you have a 64MB SDRAM module, set
3301 it above 400_0000. Just make sure your board has no resources
3302 that are supposed to respond to that address! That code in
3303 start.S has been around a while and should work as is when
3304 you get the config right.
3309 It is essential to remember this, since it has some impact on the C
3310 code for the initialization procedures:
3312 * Initialized global data (data segment) is read-only. Do not attempt
3315 * Do not use any unitialized global data (or implicitely initialized
3316 as zero data - BSS segment) at all - this is undefined, initiali-
3317 zation is performed later (when relocating to RAM).
3319 * Stack space is very limited. Avoid big data buffers or things like
3322 Having only the stack as writable memory limits means we cannot use
3323 normal global data to share information beween the code. But it
3324 turned out that the implementation of U-Boot can be greatly
3325 simplified by making a global data structure (gd_t) available to all
3326 functions. We could pass a pointer to this data as argument to _all_
3327 functions, but this would bloat the code. Instead we use a feature of
3328 the GCC compiler (Global Register Variables) to share the data: we
3329 place a pointer (gd) to the global data into a register which we
3330 reserve for this purpose.
3332 When choosing a register for such a purpose we are restricted by the
3333 relevant (E)ABI specifications for the current architecture, and by
3334 GCC's implementation.
3336 For PowerPC, the following registers have specific use:
3339 R3-R4: parameter passing and return values
3340 R5-R10: parameter passing
3341 R13: small data area pointer
3345 (U-Boot also uses R14 as internal GOT pointer.)
3347 ==> U-Boot will use R29 to hold a pointer to the global data
3349 Note: on PPC, we could use a static initializer (since the
3350 address of the global data structure is known at compile time),
3351 but it turned out that reserving a register results in somewhat
3352 smaller code - although the code savings are not that big (on
3353 average for all boards 752 bytes for the whole U-Boot image,
3354 624 text + 127 data).
3356 On ARM, the following registers are used:
3358 R0: function argument word/integer result
3359 R1-R3: function argument word
3361 R10: stack limit (used only if stack checking if enabled)
3362 R11: argument (frame) pointer
3363 R12: temporary workspace
3366 R15: program counter
3368 ==> U-Boot will use R8 to hold a pointer to the global data
3370 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
3371 or current versions of GCC may "optimize" the code too much.
3376 U-Boot runs in system state and uses physical addresses, i.e. the
3377 MMU is not used either for address mapping nor for memory protection.
3379 The available memory is mapped to fixed addresses using the memory
3380 controller. In this process, a contiguous block is formed for each
3381 memory type (Flash, SDRAM, SRAM), even when it consists of several
3382 physical memory banks.
3384 U-Boot is installed in the first 128 kB of the first Flash bank (on
3385 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3386 booting and sizing and initializing DRAM, the code relocates itself
3387 to the upper end of DRAM. Immediately below the U-Boot code some
3388 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3389 configuration setting]. Below that, a structure with global Board
3390 Info data is placed, followed by the stack (growing downward).
3392 Additionally, some exception handler code is copied to the low 8 kB
3393 of DRAM (0x00000000 ... 0x00001FFF).
3395 So a typical memory configuration with 16 MB of DRAM could look like
3398 0x0000 0000 Exception Vector code
3401 0x0000 2000 Free for Application Use
3407 0x00FB FF20 Monitor Stack (Growing downward)
3408 0x00FB FFAC Board Info Data and permanent copy of global data
3409 0x00FC 0000 Malloc Arena
3412 0x00FE 0000 RAM Copy of Monitor Code
3413 ... eventually: LCD or video framebuffer
3414 ... eventually: pRAM (Protected RAM - unchanged by reset)
3415 0x00FF FFFF [End of RAM]
3418 System Initialization:
3419 ----------------------
3421 In the reset configuration, U-Boot starts at the reset entry point
3422 (on most PowerPC systens at address 0x00000100). Because of the reset
3423 configuration for CS0# this is a mirror of the onboard Flash memory.
3424 To be able to re-map memory U-Boot then jumps to its link address.
3425 To be able to implement the initialization code in C, a (small!)
3426 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3427 which provide such a feature like MPC8xx or MPC8260), or in a locked
3428 part of the data cache. After that, U-Boot initializes the CPU core,
3429 the caches and the SIU.
3431 Next, all (potentially) available memory banks are mapped using a
3432 preliminary mapping. For example, we put them on 512 MB boundaries
3433 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3434 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3435 programmed for SDRAM access. Using the temporary configuration, a
3436 simple memory test is run that determines the size of the SDRAM
3439 When there is more than one SDRAM bank, and the banks are of
3440 different size, the largest is mapped first. For equal size, the first
3441 bank (CS2#) is mapped first. The first mapping is always for address
3442 0x00000000, with any additional banks following immediately to create
3443 contiguous memory starting from 0.
3445 Then, the monitor installs itself at the upper end of the SDRAM area
3446 and allocates memory for use by malloc() and for the global Board
3447 Info data; also, the exception vector code is copied to the low RAM
3448 pages, and the final stack is set up.
3450 Only after this relocation will you have a "normal" C environment;
3451 until that you are restricted in several ways, mostly because you are
3452 running from ROM, and because the code will have to be relocated to a
3456 U-Boot Porting Guide:
3457 ----------------------
3459 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3463 int main (int argc, char *argv[])
3465 sighandler_t no_more_time;
3467 signal (SIGALRM, no_more_time);
3468 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3470 if (available_money > available_manpower) {
3471 pay consultant to port U-Boot;
3475 Download latest U-Boot source;
3477 Subscribe to u-boot-users mailing list;
3480 email ("Hi, I am new to U-Boot, how do I get started?");
3484 Read the README file in the top level directory;
3485 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3486 Read the source, Luke;
3489 if (available_money > toLocalCurrency ($2500)) {
3492 Add a lot of aggravation and time;
3495 Create your own board support subdirectory;
3497 Create your own board config file;
3501 Add / modify source code;
3505 email ("Hi, I am having problems...");
3507 Send patch file to Wolfgang;
3512 void no_more_time (int sig)
3521 All contributions to U-Boot should conform to the Linux kernel
3522 coding style; see the file "Documentation/CodingStyle" and the script
3523 "scripts/Lindent" in your Linux kernel source directory. In sources
3524 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
3525 spaces before parameters to function calls) is actually used.
3527 Source files originating from a different project (for example the
3528 MTD subsystem) are generally exempt from these guidelines and are not
3529 reformated to ease subsequent migration to newer versions of those
3532 Please note that U-Boot is implemented in C (and to some small parts in
3533 Assembler); no C++ is used, so please do not use C++ style comments (//)
3536 Please also stick to the following formatting rules:
3537 - remove any trailing white space
3538 - use TAB characters for indentation, not spaces
3539 - make sure NOT to use DOS '\r\n' line feeds
3540 - do not add more than 2 empty lines to source files
3541 - do not add trailing empty lines to source files
3543 Submissions which do not conform to the standards may be returned
3544 with a request to reformat the changes.
3550 Since the number of patches for U-Boot is growing, we need to
3551 establish some rules. Submissions which do not conform to these rules
3552 may be rejected, even when they contain important and valuable stuff.
3554 Patches shall be sent to the u-boot-users mailing list.
3556 When you send a patch, please include the following information with
3559 * For bug fixes: a description of the bug and how your patch fixes
3560 this bug. Please try to include a way of demonstrating that the
3561 patch actually fixes something.
3563 * For new features: a description of the feature and your
3566 * A CHANGELOG entry as plaintext (separate from the patch)
3568 * For major contributions, your entry to the CREDITS file
3570 * When you add support for a new board, don't forget to add this
3571 board to the MAKEALL script, too.
3573 * If your patch adds new configuration options, don't forget to
3574 document these in the README file.
3576 * The patch itself. If you are accessing the CVS repository use "cvs
3577 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3578 version of diff does not support these options, then get the latest
3579 version of GNU diff.
3581 The current directory when running this command shall be the top
3582 level directory of the U-Boot source tree, or it's parent directory
3583 (i. e. please make sure that your patch includes sufficient
3584 directory information for the affected files).
3586 We accept patches as plain text, MIME attachments or as uuencoded
3589 * If one logical set of modifications affects or creates several
3590 files, all these changes shall be submitted in a SINGLE patch file.
3592 * Changesets that contain different, unrelated modifications shall be
3593 submitted as SEPARATE patches, one patch per changeset.
3598 * Before sending the patch, run the MAKEALL script on your patched
3599 source tree and make sure that no errors or warnings are reported
3600 for any of the boards.
3602 * Keep your modifications to the necessary minimum: A patch
3603 containing several unrelated changes or arbitrary reformats will be
3604 returned with a request to re-formatting / split it.
3606 * If you modify existing code, make sure that your new code does not
3607 add to the memory footprint of the code ;-) Small is beautiful!
3608 When adding new features, these should compile conditionally only
3609 (using #ifdef), and the resulting code with the new feature
3610 disabled must not need more memory than the old code without your
3613 * Remember that there is a size limit of 40 kB per message on the
3614 u-boot-users mailing list. Compression may help.
projects / platform / kernel / u-boot.git / blob