2 # (C) Copyright 2000 - 2004
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 and ARM processors, which can be
29 installed in a boot ROM and used to initialize and test the hardware
30 or to download and run application code.
32 The development of U-Boot is closely related to Linux: some parts of
33 the source code originate in the Linux source tree, we have some
34 header files in common, and special provision has been made to
35 support booting of Linux images.
37 Some attention has been paid to make this software easily
38 configurable and extendable. For instance, all monitor commands are
39 implemented with the same call interface, so that it's very easy to
40 add new commands. Also, instead of permanently adding rarely used
41 code (for instance hardware test utilities) to the monitor, you can
42 load and run it dynamically.
48 In general, all boards for which a configuration option exists in the
49 Makefile have been tested to some extent and can be considered
50 "working". In fact, many of them are used in production systems.
52 In case of problems see the CHANGELOG and CREDITS files to find out
53 who contributed the specific port.
59 In case you have questions about, problems with or contributions for
60 U-Boot you should send a message to the U-Boot mailing list at
61 <u-boot-users@lists.sourceforge.net>. There is also an archive of
62 previous traffic on the mailing list - please search the archive
63 before asking FAQ's. Please see
64 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
70 - start from 8xxrom sources
71 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
73 - make it easier to add custom boards
74 - make it possible to add other [PowerPC] CPUs
75 - extend functions, especially:
76 * Provide extended interface to Linux boot loader
79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
80 - create ARMBoot project (http://sourceforge.net/projects/armboot)
81 - add other CPU families (starting with ARM)
82 - create U-Boot project (http://sourceforge.net/projects/u-boot)
88 The "official" name of this project is "Das U-Boot". The spelling
89 "U-Boot" shall be used in all written text (documentation, comments
90 in source files etc.). Example:
92 This is the README file for the U-Boot project.
94 File names etc. shall be based on the string "u-boot". Examples:
96 include/asm-ppc/u-boot.h
98 #include <asm/u-boot.h>
100 Variable names, preprocessor constants etc. shall be either based on
101 the string "u_boot" or on "U_BOOT". Example:
103 U_BOOT_VERSION u_boot_logo
104 IH_OS_U_BOOT u_boot_hush_start
110 U-Boot uses a 3 level version number containing a version, a
111 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
112 sub-version "34", and patchlevel "4".
114 The patchlevel is used to indicate certain stages of development
115 between released versions, i. e. officially released versions of
116 U-Boot will always have a patchlevel of "0".
122 - board Board dependent files
123 - common Misc architecture independent functions
124 - cpu CPU specific files
125 - disk Code for disk drive partition handling
126 - doc Documentation (don't expect too much)
127 - drivers Commonly used device drivers
128 - dtt Digital Thermometer and Thermostat drivers
129 - examples Example code for standalone applications, etc.
130 - include Header Files
131 - disk Harddisk interface code
132 - net Networking code
133 - ppc Files generic to PowerPC architecture
134 - post Power On Self Test
135 - post/arch Symlink to architecture specific Power On Self Test
136 - post/arch-ppc PowerPC architecture specific Power On Self Test
137 - post/cpu/mpc8260 MPC8260 CPU specific Power On Self Test
138 - post/cpu/mpc8xx MPC8xx CPU specific Power On Self Test
139 - rtc Real Time Clock drivers
140 - tools Tools to build S-Record or U-Boot images, etc.
142 - cpu/74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
143 - cpu/arm925t Files specific to ARM 925 CPUs
144 - cpu/arm926ejs Files specific to ARM 926 CPUs
145 - cpu/mpc5xx Files specific to Motorola MPC5xx CPUs
146 - cpu/mpc8xx Files specific to Motorola MPC8xx CPUs
147 - cpu/mpc824x Files specific to Motorola MPC824x CPUs
148 - cpu/mpc8260 Files specific to Motorola MPC8260 CPU
149 - cpu/mpc85xx Files specific to Motorola MPC85xx CPUs
150 - cpu/ppc4xx Files specific to IBM 4xx CPUs
153 - board/LEOX/ Files specific to boards manufactured by The LEOX team
154 - board/LEOX/elpt860 Files specific to ELPT860 boards
156 Files specific to RPXClassic boards
157 - board/RPXlite Files specific to RPXlite boards
158 - board/at91rm9200dk Files specific to AT91RM9200DK boards
159 - board/c2mon Files specific to c2mon boards
160 - board/cmi Files specific to cmi boards
161 - board/cogent Files specific to Cogent boards
162 (need further configuration)
163 Files specific to CPCIISER4 boards
164 - board/cpu86 Files specific to CPU86 boards
165 - board/cray/ Files specific to boards manufactured by Cray
166 - board/cray/L1 Files specific to L1 boards
167 - board/cu824 Files specific to CU824 boards
168 - board/ebony Files specific to IBM Ebony board
169 - board/eric Files specific to ERIC boards
170 - board/esd/ Files specific to boards manufactured by ESD
171 - board/esd/adciop Files specific to ADCIOP boards
172 - board/esd/ar405 Files specific to AR405 boards
173 - board/esd/canbt Files specific to CANBT boards
174 - board/esd/cpci405 Files specific to CPCI405 boards
175 - board/esd/cpciiser4 Files specific to CPCIISER4 boards
176 - board/esd/common Common files for ESD boards
177 - board/esd/dasa_sim Files specific to DASA_SIM boards
178 - board/esd/du405 Files specific to DU405 boards
179 - board/esd/ocrtc Files specific to OCRTC boards
180 - board/esd/pci405 Files specific to PCI405 boards
182 Files specific to ESTEEM192E boards
183 - board/etx094 Files specific to ETX_094 boards
185 Files specific to EVB64260 boards
186 - board/fads Files specific to FADS boards
187 - board/flagadm Files specific to FLAGADM boards
188 - board/gen860t Files specific to GEN860T and GEN860T_SC boards
189 - board/genietv Files specific to GENIETV boards
190 - board/gth Files specific to GTH boards
191 - board/hermes Files specific to HERMES boards
192 - board/hymod Files specific to HYMOD boards
193 - board/icu862 Files specific to ICU862 boards
194 - board/ip860 Files specific to IP860 boards
196 Files specific to Interphase4539 boards
197 - board/ivm Files specific to IVMS8/IVML24 boards
198 - board/lantec Files specific to LANTEC boards
199 - board/lwmon Files specific to LWMON boards
200 - board/Marvell Files specific to Marvell development boards
201 - board/Marvell/db64360 Files specific to db64360 board
202 - board/Marvell/db64460 Files specific to db64460 board
203 - board/mbx8xx Files specific to MBX boards
205 Files specific to MPC826xADS and PQ2FADS-ZU/VR boards
207 Files specific to MPC8540ADS boards
209 Files specific to MPC8560ADS boards
210 - board/mpl/ Files specific to boards manufactured by MPL
211 - board/mpl/common Common files for MPL boards
212 - board/mpl/pip405 Files specific to PIP405 boards
213 - board/mpl/mip405 Files specific to MIP405 boards
214 - board/mpl/vcma9 Files specific to VCMA9 boards
215 - board/musenki Files specific to MUSEKNI boards
216 - board/mvs1 Files specific to MVS1 boards
217 - board/nx823 Files specific to NX823 boards
218 - board/oxc Files specific to OXC boards
220 Files specific to OMAP 1510 Innovator boards
222 Files specific to OMAP 1610 Innovator boards
223 - board/pcippc2 Files specific to PCIPPC2/PCIPPC6 boards
224 - board/pm826 Files specific to PM826 boards
226 Files specific to PPMC8260 boards
227 - board/snmc/qs850 Files specific to QS850/823 boards
228 - board/snmc/qs860t Files specific to QS860T boards
230 Files specific to RPXsuper boards
232 Files specific to RSDproto boards
234 Files specific to Sandpoint boards
235 - board/sbc8260 Files specific to SBC8260 boards
236 - board/sacsng Files specific to SACSng boards
237 - board/siemens Files specific to boards manufactured by Siemens AG
238 - board/siemens/CCM Files specific to CCM boards
239 - board/siemens/IAD210 Files specific to IAD210 boards
240 - board/siemens/SCM Files specific to SCM boards
241 - board/siemens/pcu_e Files specific to PCU_E boards
242 - board/sixnet Files specific to SIXNET boards
243 - board/spd8xx Files specific to SPD8xxTS boards
244 - board/tqm8260 Files specific to TQM8260 boards
245 - board/tqm8xx Files specific to TQM8xxL boards
246 - board/w7o Files specific to W7O boards
248 Files specific to Walnut405 boards
249 - board/westel/ Files specific to boards manufactured by Westel Wireless
250 - board/westel/amx860 Files specific to AMX860 boards
251 - board/utx8245 Files specific to UTX8245 boards
252 - board/zpc1900 Files specific to Zephyr Engineering ZPC.1900 board
254 Software Configuration:
255 =======================
257 Configuration is usually done using C preprocessor defines; the
258 rationale behind that is to avoid dead code whenever possible.
260 There are two classes of configuration variables:
262 * Configuration _OPTIONS_:
263 These are selectable by the user and have names beginning with
266 * Configuration _SETTINGS_:
267 These depend on the hardware etc. and should not be meddled with if
268 you don't know what you're doing; they have names beginning with
271 Later we will add a configuration tool - probably similar to or even
272 identical to what's used for the Linux kernel. Right now, we have to
273 do the configuration by hand, which means creating some symbolic
274 links and editing some configuration files. We use the TQM8xxL boards
278 Selection of Processor Architecture and Board Type:
279 ---------------------------------------------------
281 For all supported boards there are ready-to-use default
282 configurations available; just type "make <board_name>_config".
284 Example: For a TQM823L module type:
289 For the Cogent platform, you need to specify the cpu type as well;
290 e.g. "make cogent_mpc8xx_config". And also configure the cogent
291 directory according to the instructions in cogent/README.
294 Configuration Options:
295 ----------------------
297 Configuration depends on the combination of board and CPU type; all
298 such information is kept in a configuration file
299 "include/configs/<board_name>.h".
301 Example: For a TQM823L module, all configuration settings are in
302 "include/configs/TQM823L.h".
305 Many of the options are named exactly as the corresponding Linux
306 kernel configuration options. The intention is to make it easier to
307 build a config tool - later.
310 The following options need to be configured:
312 - CPU Type: Define exactly one of
316 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
318 or CONFIG_MPC824X, CONFIG_MPC8260
334 - Board Type: Define exactly one of
336 PowerPC based boards:
337 ---------------------
339 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper,
340 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850,
341 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS,
342 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T,
343 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240,
344 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245,
345 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L,
346 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L,
347 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L,
348 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L,
349 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260,
350 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech,
351 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245,
352 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC,
353 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG,
354 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405,
355 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA,
356 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon,
357 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260,
358 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx,
359 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260,
360 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260,
361 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes,
362 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod,
363 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon,
364 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e,
365 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260,
366 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto,
367 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260,
368 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L,
369 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI,
370 CONFIG_NETVIA, CONFIG_RBC823, CONFIG_ZPC1900,
371 CONFIG_MPC8540ADS, CONFIG_MPC8560ADS, CONFIG_QS850,
372 CONFIG_QS823, CONFIG_QS860T, CONFIG_DB64360,
373 CONFIG_DB64460, CONFIG_DUET_ADS
378 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312,
379 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK,
380 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610
381 CONFIG_SHANNON, CONFIG_SMDK2400, CONFIG_SMDK2410,
382 CONFIG_TRAB, CONFIG_VCMA9, CONFIG_AT91RM9200DK
385 - CPU Module Type: (if CONFIG_COGENT is defined)
386 Define exactly one of
388 --- FIXME --- not tested yet:
389 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
390 CONFIG_CMA287_23, CONFIG_CMA287_50
392 - Motherboard Type: (if CONFIG_COGENT is defined)
393 Define exactly one of
394 CONFIG_CMA101, CONFIG_CMA102
396 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
397 Define one or more of
400 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
401 Define one or more of
402 CONFIG_LCD_HEARTBEAT - update a character position on
403 the lcd display every second with
406 - Board flavour: (if CONFIG_MPC8260ADS is defined)
409 CFG_8260ADS - original MPC8260ADS
410 CFG_8266ADS - MPC8266ADS
411 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
414 - MPC824X Family Member (if CONFIG_MPC824X is defined)
415 Define exactly one of
416 CONFIG_MPC8240, CONFIG_MPC8245
418 - 8xx CPU Options: (if using an 8xx cpu)
419 Define one or more of
420 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work
421 e.g. if there is no 32KHz
422 reference PIT/RTC clock
424 - Linux Kernel Interface:
427 U-Boot stores all clock information in Hz
428 internally. For binary compatibility with older Linux
429 kernels (which expect the clocks passed in the
430 bd_info data to be in MHz) the environment variable
431 "clocks_in_mhz" can be defined so that U-Boot
432 converts clock data to MHZ before passing it to the
434 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
435 "clocks_in_mhz=1" is automatically included in the
438 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
440 When transfering memsize parameter to linux, some versions
441 expect it to be in bytes, others in MB.
442 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
445 Depending on board, define exactly one serial port
446 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
447 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
448 console by defining CONFIG_8xx_CONS_NONE
450 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
451 port routines must be defined elsewhere
452 (i.e. serial_init(), serial_getc(), ...)
455 Enables console device for a color framebuffer. Needs following
456 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
457 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
459 VIDEO_HW_RECTFILL graphic chip supports
462 VIDEO_HW_BITBLT graphic chip supports
463 bit-blit (cf. smiLynxEM)
464 VIDEO_VISIBLE_COLS visible pixel columns
466 VIDEO_VISIBLE_ROWS visible pixel rows
467 VIDEO_PIXEL_SIZE bytes per pixel
468 VIDEO_DATA_FORMAT graphic data format
469 (0-5, cf. cfb_console.c)
470 VIDEO_FB_ADRS framebuffer address
471 VIDEO_KBD_INIT_FCT keyboard int fct
472 (i.e. i8042_kbd_init())
473 VIDEO_TSTC_FCT test char fct
475 VIDEO_GETC_FCT get char fct
477 CONFIG_CONSOLE_CURSOR cursor drawing on/off
478 (requires blink timer
480 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
481 CONFIG_CONSOLE_TIME display time/date info in
483 (requires CFG_CMD_DATE)
484 CONFIG_VIDEO_LOGO display Linux logo in
486 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
487 linux_logo.h for logo.
488 Requires CONFIG_VIDEO_LOGO
489 CONFIG_CONSOLE_EXTRA_INFO
490 addional board info beside
493 When CONFIG_CFB_CONSOLE is defined, video console is
494 default i/o. Serial console can be forced with
495 environment 'console=serial'.
497 When CONFIG_SILENT_CONSOLE is defined, all console
498 messages (by U-Boot and Linux!) can be silenced with
499 the "silent" environment variable. See
500 doc/README.silent for more information.
503 CONFIG_BAUDRATE - in bps
504 Select one of the baudrates listed in
505 CFG_BAUDRATE_TABLE, see below.
506 CFG_BRGCLK_PRESCALE, baudrate prescale
508 - Interrupt driven serial port input:
509 CONFIG_SERIAL_SOFTWARE_FIFO
512 Use an interrupt handler for receiving data on the
513 serial port. It also enables using hardware handshake
514 (RTS/CTS) and UART's built-in FIFO. Set the number of
515 bytes the interrupt driven input buffer should have.
517 Set to 0 to disable this feature (this is the default).
518 This will also disable hardware handshake.
520 - Console UART Number:
524 If defined internal UART1 (and not UART0) is used
525 as default U-Boot console.
527 - Boot Delay: CONFIG_BOOTDELAY - in seconds
528 Delay before automatically booting the default image;
529 set to -1 to disable autoboot.
531 See doc/README.autoboot for these options that
532 work with CONFIG_BOOTDELAY. None are required.
533 CONFIG_BOOT_RETRY_TIME
534 CONFIG_BOOT_RETRY_MIN
535 CONFIG_AUTOBOOT_KEYED
536 CONFIG_AUTOBOOT_PROMPT
537 CONFIG_AUTOBOOT_DELAY_STR
538 CONFIG_AUTOBOOT_STOP_STR
539 CONFIG_AUTOBOOT_DELAY_STR2
540 CONFIG_AUTOBOOT_STOP_STR2
541 CONFIG_ZERO_BOOTDELAY_CHECK
542 CONFIG_RESET_TO_RETRY
546 Only needed when CONFIG_BOOTDELAY is enabled;
547 define a command string that is automatically executed
548 when no character is read on the console interface
549 within "Boot Delay" after reset.
552 This can be used to pass arguments to the bootm
553 command. The value of CONFIG_BOOTARGS goes into the
554 environment value "bootargs".
556 CONFIG_RAMBOOT and CONFIG_NFSBOOT
557 The value of these goes into the environment as
558 "ramboot" and "nfsboot" respectively, and can be used
559 as a convenience, when switching between booting from
565 When this option is #defined, the existence of the
566 environment variable "preboot" will be checked
567 immediately before starting the CONFIG_BOOTDELAY
568 countdown and/or running the auto-boot command resp.
569 entering interactive mode.
571 This feature is especially useful when "preboot" is
572 automatically generated or modified. For an example
573 see the LWMON board specific code: here "preboot" is
574 modified when the user holds down a certain
575 combination of keys on the (special) keyboard when
578 - Serial Download Echo Mode:
580 If defined to 1, all characters received during a
581 serial download (using the "loads" command) are
582 echoed back. This might be needed by some terminal
583 emulations (like "cu"), but may as well just take
584 time on others. This setting #define's the initial
585 value of the "loads_echo" environment variable.
587 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
589 Select one of the baudrates listed in
590 CFG_BAUDRATE_TABLE, see below.
594 Most monitor functions can be selected (or
595 de-selected) by adjusting the definition of
596 CONFIG_COMMANDS; to select individual functions,
597 #define CONFIG_COMMANDS by "OR"ing any of the
600 #define enables commands:
601 -------------------------
602 CFG_CMD_ASKENV * ask for env variable
603 CFG_CMD_AUTOSCRIPT Autoscript Support
605 CFG_CMD_BEDBUG Include BedBug Debugger
606 CFG_CMD_BMP * BMP support
608 CFG_CMD_CACHE icache, dcache
609 CFG_CMD_CONSOLE coninfo
610 CFG_CMD_DATE * support for RTC, date/time...
611 CFG_CMD_DHCP DHCP support
612 CFG_CMD_DIAG * Diagnostics
613 CFG_CMD_DOC * Disk-On-Chip Support
614 CFG_CMD_DTT Digital Therm and Thermostat
615 CFG_CMD_ECHO * echo arguments
616 CFG_CMD_EEPROM * EEPROM read/write support
617 CFG_CMD_ELF bootelf, bootvx
619 CFG_CMD_FDC * Floppy Disk Support
620 CFG_CMD_FAT FAT partition support
621 CFG_CMD_FDOS * Dos diskette Support
622 CFG_CMD_FLASH flinfo, erase, protect
623 CFG_CMD_FPGA FPGA device initialization support
624 CFG_CMD_HWFLOW * RTS/CTS hw flow control
625 CFG_CMD_I2C * I2C serial bus support
626 CFG_CMD_IDE * IDE harddisk support
628 CFG_CMD_IMLS List all found images
629 CFG_CMD_IMMAP * IMMR dump support
630 CFG_CMD_IRQ * irqinfo
631 CFG_CMD_JFFS2 * JFFS2 Support
635 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
637 CFG_CMD_MISC Misc functions like sleep etc
638 CFG_CMD_MMC MMC memory mapped support
639 CFG_CMD_MII MII utility commands
640 CFG_CMD_NAND * NAND support
641 CFG_CMD_NET bootp, tftpboot, rarpboot
642 CFG_CMD_PCI * pciinfo
643 CFG_CMD_PCMCIA * PCMCIA support
644 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
645 CFG_CMD_PORTIO * Port I/O
646 CFG_CMD_REGINFO * Register dump
647 CFG_CMD_RUN run command in env variable
648 CFG_CMD_SAVES save S record dump
649 CFG_CMD_SCSI * SCSI Support
650 CFG_CMD_SDRAM * print SDRAM configuration information
651 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
652 CFG_CMD_SPI * SPI serial bus support
653 CFG_CMD_USB * USB support
654 CFG_CMD_VFD * VFD support (TRAB)
655 CFG_CMD_BSP * Board SPecific functions
656 -----------------------------------------------
659 CFG_CMD_DFL Default configuration; at the moment
660 this is includes all commands, except
661 the ones marked with "*" in the list
664 If you don't define CONFIG_COMMANDS it defaults to
665 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
666 override the default settings in the respective
669 EXAMPLE: If you want all functions except of network
670 support you can write:
672 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
675 Note: Don't enable the "icache" and "dcache" commands
676 (configuration option CFG_CMD_CACHE) unless you know
677 what you (and your U-Boot users) are doing. Data
678 cache cannot be enabled on systems like the 8xx or
679 8260 (where accesses to the IMMR region must be
680 uncached), and it cannot be disabled on all other
681 systems where we (mis-) use the data cache to hold an
682 initial stack and some data.
685 XXX - this list needs to get updated!
689 If this variable is defined, it enables watchdog
690 support. There must be support in the platform specific
691 code for a watchdog. For the 8xx and 8260 CPUs, the
692 SIU Watchdog feature is enabled in the SYPCR
696 CONFIG_VERSION_VARIABLE
697 If this variable is defined, an environment variable
698 named "ver" is created by U-Boot showing the U-Boot
699 version as printed by the "version" command.
700 This variable is readonly.
704 When CFG_CMD_DATE is selected, the type of the RTC
705 has to be selected, too. Define exactly one of the
708 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
709 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
710 CONFIG_RTC_MC146818 - use MC146818 RTC
711 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
712 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
713 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
714 CONFIG_RTC_DS164x - use Dallas DS164x RTC
716 Note that if the RTC uses I2C, then the I2C interface
717 must also be configured. See I2C Support, below.
721 When CONFIG_TIMESTAMP is selected, the timestamp
722 (date and time) of an image is printed by image
723 commands like bootm or iminfo. This option is
724 automatically enabled when you select CFG_CMD_DATE .
727 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
728 and/or CONFIG_ISO_PARTITION
730 If IDE or SCSI support is enabled (CFG_CMD_IDE or
731 CFG_CMD_SCSI) you must configure support for at least
732 one partition type as well.
735 CONFIG_IDE_RESET_ROUTINE
737 Set this to define that instead of a reset Pin, the
738 routine ide_set_reset(int idereset) will be used.
743 Set this to enable ATAPI support.
746 At the moment only there is only support for the
747 SYM53C8XX SCSI controller; define
748 CONFIG_SCSI_SYM53C8XX to enable it.
750 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
751 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
752 CFG_SCSI_MAX_LUN] can be adjusted to define the
753 maximum numbers of LUNs, SCSI ID's and target
755 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
757 - NETWORK Support (PCI):
759 Support for Intel 8254x gigabit chips.
762 Support for Intel 82557/82559/82559ER chips.
763 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
764 write routine for first time initialisation.
767 Support for Digital 2114x chips.
768 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
769 modem chip initialisation (KS8761/QS6611).
772 Support for National dp83815 chips.
775 Support for National dp8382[01] gigabit chips.
777 - NETWORK Support (other):
779 CONFIG_DRIVER_LAN91C96
780 Support for SMSC's LAN91C96 chips.
783 Define this to hold the physical address
784 of the LAN91C96's I/O space
786 CONFIG_LAN91C96_USE_32_BIT
787 Define this to enable 32 bit addressing
790 At the moment only the UHCI host controller is
791 supported (PIP405, MIP405); define
792 CONFIG_USB_UHCI to enable it.
793 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
794 end define CONFIG_USB_STORAGE to enable the USB
797 Supported are USB Keyboards and USB Floppy drives
801 The MMC controller on the Intel PXA is supported. To
802 enable this define CONFIG_MMC. The MMC can be
803 accessed from the boot prompt by mapping the device
804 to physical memory similar to flash. Command line is
805 enabled with CFG_CMD_MMC. The MMC driver also works with
806 the FAT fs. This is enabled with CFG_CMD_FAT.
811 Define this to enable standard (PC-Style) keyboard
815 Standard PC keyboard driver with US (is default) and
816 GERMAN key layout (switch via environment 'keymap=de') support.
817 Export function i8042_kbd_init, i8042_tstc and i8042_getc
818 for cfb_console. Supports cursor blinking.
823 Define this to enable video support (for output to
828 Enable Chips & Technologies 69000 Video chip
830 CONFIG_VIDEO_SMI_LYNXEM
831 Enable Silicon Motion SMI 712/710/810 Video chip
832 Videomode are selected via environment 'videomode' with
833 standard LiLo mode numbers.
834 Following modes are supported (* is default):
836 800x600 1024x768 1280x1024
837 256 (8bit) 303* 305 307
838 65536 (16bit) 314 317 31a
839 16,7 Mill (24bit) 315 318 31b
840 (i.e. setenv videomode 317; saveenv; reset;)
842 CONFIG_VIDEO_SED13806
843 Enable Epson SED13806 driver. This driver supports 8bpp
844 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
845 or CONFIG_VIDEO_SED13806_16BPP
850 Define this to enable a custom keyboard support.
851 This simply calls drv_keyboard_init() which must be
852 defined in your board-specific files.
853 The only board using this so far is RBC823.
855 - LCD Support: CONFIG_LCD
857 Define this to enable LCD support (for output to LCD
858 display); also select one of the supported displays
859 by defining one of these:
861 CONFIG_NEC_NL6448AC33:
863 NEC NL6448AC33-18. Active, color, single scan.
865 CONFIG_NEC_NL6448BC20
867 NEC NL6448BC20-08. 6.5", 640x480.
868 Active, color, single scan.
870 CONFIG_NEC_NL6448BC33_54
872 NEC NL6448BC33-54. 10.4", 640x480.
873 Active, color, single scan.
877 Sharp 320x240. Active, color, single scan.
878 It isn't 16x9, and I am not sure what it is.
880 CONFIG_SHARP_LQ64D341
882 Sharp LQ64D341 display, 640x480.
883 Active, color, single scan.
887 HLD1045 display, 640x480.
888 Active, color, single scan.
892 Optrex CBL50840-2 NF-FW 99 22 M5
894 Hitachi LMG6912RPFC-00T
898 320x240. Black & white.
900 Normally display is black on white background; define
901 CFG_WHITE_ON_BLACK to get it inverted.
903 - Splash Screen Support: CONFIG_SPLASH_SCREEN
905 If this option is set, the environment is checked for
906 a variable "splashimage". If found, the usual display
907 of logo, copyright and system information on the LCD
908 is supressed and the BMP image at the address
909 specified in "splashimage" is loaded instead. The
910 console is redirected to the "nulldev", too. This
911 allows for a "silent" boot where a splash screen is
912 loaded very quickly after power-on.
914 - Compression support:
917 If this option is set, support for bzip2 compressed
918 images is included. If not, only uncompressed and gzip
919 compressed images are supported.
921 NOTE: the bzip2 algorithm requires a lot of RAM, so
922 the malloc area (as defined by CFG_MALLOC_LEN) should
930 Define a default value for ethernet address to use
931 for the respective ethernet interface, in case this
932 is not determined automatically.
937 Define a default value for the IP address to use for
938 the default ethernet interface, in case this is not
939 determined through e.g. bootp.
944 Defines a default value for theIP address of a TFTP
945 server to contact when using the "tftboot" command.
947 - BOOTP Recovery Mode:
948 CONFIG_BOOTP_RANDOM_DELAY
950 If you have many targets in a network that try to
951 boot using BOOTP, you may want to avoid that all
952 systems send out BOOTP requests at precisely the same
953 moment (which would happen for instance at recovery
954 from a power failure, when all systems will try to
955 boot, thus flooding the BOOTP server. Defining
956 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
957 inserted before sending out BOOTP requests. The
958 following delays are insterted then:
960 1st BOOTP request: delay 0 ... 1 sec
961 2nd BOOTP request: delay 0 ... 2 sec
962 3rd BOOTP request: delay 0 ... 4 sec
964 BOOTP requests: delay 0 ... 8 sec
966 - DHCP Advanced Options:
969 You can fine tune the DHCP functionality by adding
970 these flags to the CONFIG_BOOTP_MASK define:
972 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
973 serverip from a DHCP server, it is possible that more
974 than one DNS serverip is offered to the client.
975 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
976 serverip will be stored in the additional environment
977 variable "dnsip2". The first DNS serverip is always
978 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
979 is added to the CONFIG_BOOTP_MASK.
981 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
982 to do a dynamic update of a DNS server. To do this, they
983 need the hostname of the DHCP requester.
984 If CONFIG_BOOP_SEND_HOSTNAME is added to the
985 CONFIG_BOOTP_MASK, the content of the "hostname"
986 environment variable is passed as option 12 to
989 - Status LED: CONFIG_STATUS_LED
991 Several configurations allow to display the current
992 status using a LED. For instance, the LED will blink
993 fast while running U-Boot code, stop blinking as
994 soon as a reply to a BOOTP request was received, and
995 start blinking slow once the Linux kernel is running
996 (supported by a status LED driver in the Linux
997 kernel). Defining CONFIG_STATUS_LED enables this
1000 - CAN Support: CONFIG_CAN_DRIVER
1002 Defining CONFIG_CAN_DRIVER enables CAN driver support
1003 on those systems that support this (optional)
1004 feature, like the TQM8xxL modules.
1006 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1008 These enable I2C serial bus commands. Defining either of
1009 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1010 include the appropriate I2C driver for the selected cpu.
1012 This will allow you to use i2c commands at the u-boot
1013 command line (as long as you set CFG_CMD_I2C in
1014 CONFIG_COMMANDS) and communicate with i2c based realtime
1015 clock chips. See common/cmd_i2c.c for a description of the
1016 command line interface.
1018 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1020 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1021 bit-banging) driver instead of CPM or similar hardware
1024 There are several other quantities that must also be
1025 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1027 In both cases you will need to define CFG_I2C_SPEED
1028 to be the frequency (in Hz) at which you wish your i2c bus
1029 to run and CFG_I2C_SLAVE to be the address of this node (ie
1030 the cpu's i2c node address).
1032 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1033 sets the cpu up as a master node and so its address should
1034 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1035 p.16-473). So, set CFG_I2C_SLAVE to 0.
1037 That's all that's required for CONFIG_HARD_I2C.
1039 If you use the software i2c interface (CONFIG_SOFT_I2C)
1040 then the following macros need to be defined (examples are
1041 from include/configs/lwmon.h):
1045 (Optional). Any commands necessary to enable the I2C
1046 controller or configure ports.
1048 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1052 (Only for MPC8260 CPU). The I/O port to use (the code
1053 assumes both bits are on the same port). Valid values
1054 are 0..3 for ports A..D.
1058 The code necessary to make the I2C data line active
1059 (driven). If the data line is open collector, this
1062 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1066 The code necessary to make the I2C data line tri-stated
1067 (inactive). If the data line is open collector, this
1070 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1074 Code that returns TRUE if the I2C data line is high,
1077 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1081 If <bit> is TRUE, sets the I2C data line high. If it
1082 is FALSE, it clears it (low).
1084 eg: #define I2C_SDA(bit) \
1085 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1086 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1090 If <bit> is TRUE, sets the I2C clock line high. If it
1091 is FALSE, it clears it (low).
1093 eg: #define I2C_SCL(bit) \
1094 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1095 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1099 This delay is invoked four times per clock cycle so this
1100 controls the rate of data transfer. The data rate thus
1101 is 1 / (I2C_DELAY * 4). Often defined to be something
1104 #define I2C_DELAY udelay(2)
1108 When a board is reset during an i2c bus transfer
1109 chips might think that the current transfer is still
1110 in progress. On some boards it is possible to access
1111 the i2c SCLK line directly, either by using the
1112 processor pin as a GPIO or by having a second pin
1113 connected to the bus. If this option is defined a
1114 custom i2c_init_board() routine in boards/xxx/board.c
1115 is run early in the boot sequence.
1117 - SPI Support: CONFIG_SPI
1119 Enables SPI driver (so far only tested with
1120 SPI EEPROM, also an instance works with Crystal A/D and
1121 D/As on the SACSng board)
1125 Enables extended (16-bit) SPI EEPROM addressing.
1126 (symmetrical to CONFIG_I2C_X)
1130 Enables a software (bit-bang) SPI driver rather than
1131 using hardware support. This is a general purpose
1132 driver that only requires three general I/O port pins
1133 (two outputs, one input) to function. If this is
1134 defined, the board configuration must define several
1135 SPI configuration items (port pins to use, etc). For
1136 an example, see include/configs/sacsng.h.
1138 - FPGA Support: CONFIG_FPGA_COUNT
1140 Specify the number of FPGA devices to support.
1144 Used to specify the types of FPGA devices. For
1146 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1148 CFG_FPGA_PROG_FEEDBACK
1150 Enable printing of hash marks during FPGA
1155 Enable checks on FPGA configuration interface busy
1156 status by the configuration function. This option
1157 will require a board or device specific function to
1162 If defined, a function that provides delays in the
1163 FPGA configuration driver.
1165 CFG_FPGA_CHECK_CTRLC
1167 Allow Control-C to interrupt FPGA configuration
1169 CFG_FPGA_CHECK_ERROR
1171 Check for configuration errors during FPGA bitfile
1172 loading. For example, abort during Virtex II
1173 configuration if the INIT_B line goes low (which
1174 indicated a CRC error).
1178 Maximum time to wait for the INIT_B line to deassert
1179 after PROB_B has been deasserted during a Virtex II
1180 FPGA configuration sequence. The default time is 500 mS.
1184 Maximum time to wait for BUSY to deassert during
1185 Virtex II FPGA configuration. The default is 5 mS.
1187 CFG_FPGA_WAIT_CONFIG
1189 Time to wait after FPGA configuration. The default is
1192 - FPGA Support: CONFIG_FPGA_COUNT
1194 Specify the number of FPGA devices to support.
1198 Used to specify the types of FPGA devices. For example,
1199 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1201 CFG_FPGA_PROG_FEEDBACK
1203 Enable printing of hash marks during FPGA configuration.
1207 Enable checks on FPGA configuration interface busy
1208 status by the configuration function. This option
1209 will require a board or device specific function to
1214 If defined, a function that provides delays in the FPGA
1215 configuration driver.
1217 CFG_FPGA_CHECK_CTRLC
1218 Allow Control-C to interrupt FPGA configuration
1220 CFG_FPGA_CHECK_ERROR
1222 Check for configuration errors during FPGA bitfile
1223 loading. For example, abort during Virtex II
1224 configuration if the INIT_B line goes low (which
1225 indicated a CRC error).
1229 Maximum time to wait for the INIT_B line to deassert
1230 after PROB_B has been deasserted during a Virtex II
1231 FPGA configuration sequence. The default time is 500
1236 Maximum time to wait for BUSY to deassert during
1237 Virtex II FPGA configuration. The default is 5 mS.
1239 CFG_FPGA_WAIT_CONFIG
1241 Time to wait after FPGA configuration. The default is
1244 - Configuration Management:
1247 If defined, this string will be added to the U-Boot
1248 version information (U_BOOT_VERSION)
1250 - Vendor Parameter Protection:
1252 U-Boot considers the values of the environment
1253 variables "serial#" (Board Serial Number) and
1254 "ethaddr" (Ethernet Address) to be parameters that
1255 are set once by the board vendor / manufacturer, and
1256 protects these variables from casual modification by
1257 the user. Once set, these variables are read-only,
1258 and write or delete attempts are rejected. You can
1259 change this behviour:
1261 If CONFIG_ENV_OVERWRITE is #defined in your config
1262 file, the write protection for vendor parameters is
1263 completely disabled. Anybody can change or delete
1266 Alternatively, if you #define _both_ CONFIG_ETHADDR
1267 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1268 ethernet address is installed in the environment,
1269 which can be changed exactly ONCE by the user. [The
1270 serial# is unaffected by this, i. e. it remains
1276 Define this variable to enable the reservation of
1277 "protected RAM", i. e. RAM which is not overwritten
1278 by U-Boot. Define CONFIG_PRAM to hold the number of
1279 kB you want to reserve for pRAM. You can overwrite
1280 this default value by defining an environment
1281 variable "pram" to the number of kB you want to
1282 reserve. Note that the board info structure will
1283 still show the full amount of RAM. If pRAM is
1284 reserved, a new environment variable "mem" will
1285 automatically be defined to hold the amount of
1286 remaining RAM in a form that can be passed as boot
1287 argument to Linux, for instance like that:
1289 setenv bootargs ... mem=\$(mem)
1292 This way you can tell Linux not to use this memory,
1293 either, which results in a memory region that will
1294 not be affected by reboots.
1296 *WARNING* If your board configuration uses automatic
1297 detection of the RAM size, you must make sure that
1298 this memory test is non-destructive. So far, the
1299 following board configurations are known to be
1302 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1303 HERMES, IP860, RPXlite, LWMON, LANTEC,
1304 PCU_E, FLAGADM, TQM8260
1309 Define this variable to stop the system in case of a
1310 fatal error, so that you have to reset it manually.
1311 This is probably NOT a good idea for an embedded
1312 system where you want to system to reboot
1313 automatically as fast as possible, but it may be
1314 useful during development since you can try to debug
1315 the conditions that lead to the situation.
1317 CONFIG_NET_RETRY_COUNT
1319 This variable defines the number of retries for
1320 network operations like ARP, RARP, TFTP, or BOOTP
1321 before giving up the operation. If not defined, a
1322 default value of 5 is used.
1324 - Command Interpreter:
1327 Define this variable to enable the "hush" shell (from
1328 Busybox) as command line interpreter, thus enabling
1329 powerful command line syntax like
1330 if...then...else...fi conditionals or `&&' and '||'
1331 constructs ("shell scripts").
1333 If undefined, you get the old, much simpler behaviour
1334 with a somewhat smaller memory footprint.
1339 This defines the secondary prompt string, which is
1340 printed when the command interpreter needs more input
1341 to complete a command. Usually "> ".
1345 In the current implementation, the local variables
1346 space and global environment variables space are
1347 separated. Local variables are those you define by
1348 simply typing `name=value'. To access a local
1349 variable later on, you have write `$name' or
1350 `${name}'; to execute the contents of a variable
1351 directly type `$name' at the command prompt.
1353 Global environment variables are those you use
1354 setenv/printenv to work with. To run a command stored
1355 in such a variable, you need to use the run command,
1356 and you must not use the '$' sign to access them.
1358 To store commands and special characters in a
1359 variable, please use double quotation marks
1360 surrounding the whole text of the variable, instead
1361 of the backslashes before semicolons and special
1364 - Default Environment:
1365 CONFIG_EXTRA_ENV_SETTINGS
1367 Define this to contain any number of null terminated
1368 strings (variable = value pairs) that will be part of
1369 the default environment compiled into the boot image.
1371 For example, place something like this in your
1372 board's config file:
1374 #define CONFIG_EXTRA_ENV_SETTINGS \
1378 Warning: This method is based on knowledge about the
1379 internal format how the environment is stored by the
1380 U-Boot code. This is NOT an official, exported
1381 interface! Although it is unlikely that this format
1382 will change soon, there is no guarantee either.
1383 You better know what you are doing here.
1385 Note: overly (ab)use of the default environment is
1386 discouraged. Make sure to check other ways to preset
1387 the environment like the autoscript function or the
1390 - DataFlash Support:
1391 CONFIG_HAS_DATAFLASH
1393 Defining this option enables DataFlash features and
1394 allows to read/write in Dataflash via the standard
1397 - Show boot progress:
1398 CONFIG_SHOW_BOOT_PROGRESS
1400 Defining this option allows to add some board-
1401 specific code (calling a user-provided function
1402 "show_boot_progress(int)") that enables you to show
1403 the system's boot progress on some display (for
1404 example, some LED's) on your board. At the moment,
1405 the following checkpoints are implemented:
1408 1 common/cmd_bootm.c before attempting to boot an image
1409 -1 common/cmd_bootm.c Image header has bad magic number
1410 2 common/cmd_bootm.c Image header has correct magic number
1411 -2 common/cmd_bootm.c Image header has bad checksum
1412 3 common/cmd_bootm.c Image header has correct checksum
1413 -3 common/cmd_bootm.c Image data has bad checksum
1414 4 common/cmd_bootm.c Image data has correct checksum
1415 -4 common/cmd_bootm.c Image is for unsupported architecture
1416 5 common/cmd_bootm.c Architecture check OK
1417 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1418 6 common/cmd_bootm.c Image Type check OK
1419 -6 common/cmd_bootm.c gunzip uncompression error
1420 -7 common/cmd_bootm.c Unimplemented compression type
1421 7 common/cmd_bootm.c Uncompression OK
1422 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1423 8 common/cmd_bootm.c Image Type check OK
1424 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1425 9 common/cmd_bootm.c Start initial ramdisk verification
1426 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1427 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1428 10 common/cmd_bootm.c Ramdisk header is OK
1429 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1430 11 common/cmd_bootm.c Ramdisk data has correct checksum
1431 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1432 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1433 13 common/cmd_bootm.c Start multifile image verification
1434 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1435 15 common/cmd_bootm.c All preparation done, transferring control to OS
1437 -1 common/cmd_doc.c Bad usage of "doc" command
1438 -1 common/cmd_doc.c No boot device
1439 -1 common/cmd_doc.c Unknown Chip ID on boot device
1440 -1 common/cmd_doc.c Read Error on boot device
1441 -1 common/cmd_doc.c Image header has bad magic number
1443 -1 common/cmd_ide.c Bad usage of "ide" command
1444 -1 common/cmd_ide.c No boot device
1445 -1 common/cmd_ide.c Unknown boot device
1446 -1 common/cmd_ide.c Unknown partition table
1447 -1 common/cmd_ide.c Invalid partition type
1448 -1 common/cmd_ide.c Read Error on boot device
1449 -1 common/cmd_ide.c Image header has bad magic number
1451 -1 common/cmd_nand.c Bad usage of "nand" command
1452 -1 common/cmd_nand.c No boot device
1453 -1 common/cmd_nand.c Unknown Chip ID on boot device
1454 -1 common/cmd_nand.c Read Error on boot device
1455 -1 common/cmd_nand.c Image header has bad magic number
1457 -1 common/env_common.c Environment has a bad CRC, using default
1463 [so far only for SMDK2400 and TRAB boards]
1465 - Modem support endable:
1466 CONFIG_MODEM_SUPPORT
1468 - RTS/CTS Flow control enable:
1471 - Modem debug support:
1472 CONFIG_MODEM_SUPPORT_DEBUG
1474 Enables debugging stuff (char screen[1024], dbg())
1475 for modem support. Useful only with BDI2000.
1477 - Interrupt support (PPC):
1479 There are common interrupt_init() and timer_interrupt()
1480 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1481 for cpu specific initialization. interrupt_init_cpu()
1482 should set decrementer_count to appropriate value. If
1483 cpu resets decrementer automatically after interrupt
1484 (ppc4xx) it should set decrementer_count to zero.
1485 timer_interrupt() calls timer_interrupt_cpu() for cpu
1486 specific handling. If board has watchdog / status_led
1487 / other_activity_monitor it works automatically from
1488 general timer_interrupt().
1492 In the target system modem support is enabled when a
1493 specific key (key combination) is pressed during
1494 power-on. Otherwise U-Boot will boot normally
1495 (autoboot). The key_pressed() fuction is called from
1496 board_init(). Currently key_pressed() is a dummy
1497 function, returning 1 and thus enabling modem
1500 If there are no modem init strings in the
1501 environment, U-Boot proceed to autoboot; the
1502 previous output (banner, info printfs) will be
1505 See also: doc/README.Modem
1508 Configuration Settings:
1509 -----------------------
1511 - CFG_LONGHELP: Defined when you want long help messages included;
1512 undefine this when you're short of memory.
1514 - CFG_PROMPT: This is what U-Boot prints on the console to
1515 prompt for user input.
1517 - CFG_CBSIZE: Buffer size for input from the Console
1519 - CFG_PBSIZE: Buffer size for Console output
1521 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1523 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1524 the application (usually a Linux kernel) when it is
1527 - CFG_BAUDRATE_TABLE:
1528 List of legal baudrate settings for this board.
1530 - CFG_CONSOLE_INFO_QUIET
1531 Suppress display of console information at boot.
1533 - CFG_CONSOLE_IS_IN_ENV
1534 If the board specific function
1535 extern int overwrite_console (void);
1536 returns 1, the stdin, stderr and stdout are switched to the
1537 serial port, else the settings in the environment are used.
1539 - CFG_CONSOLE_OVERWRITE_ROUTINE
1540 Enable the call to overwrite_console().
1542 - CFG_CONSOLE_ENV_OVERWRITE
1543 Enable overwrite of previous console environment settings.
1545 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1546 Begin and End addresses of the area used by the
1550 Enable an alternate, more extensive memory test.
1552 - CFG_MEMTEST_SCRATCH:
1553 Scratch address used by the alternate memory test
1554 You only need to set this if address zero isn't writeable
1556 - CFG_TFTP_LOADADDR:
1557 Default load address for network file downloads
1559 - CFG_LOADS_BAUD_CHANGE:
1560 Enable temporary baudrate change while serial download
1563 Physical start address of SDRAM. _Must_ be 0 here.
1566 Physical start address of Motherboard I/O (if using a
1570 Physical start address of Flash memory.
1573 Physical start address of boot monitor code (set by
1574 make config files to be same as the text base address
1575 (TEXT_BASE) used when linking) - same as
1576 CFG_FLASH_BASE when booting from flash.
1579 Size of memory reserved for monitor code, used to
1580 determine _at_compile_time_ (!) if the environment is
1581 embedded within the U-Boot image, or in a separate
1585 Size of DRAM reserved for malloc() use.
1588 Maximum size of memory mapped by the startup code of
1589 the Linux kernel; all data that must be processed by
1590 the Linux kernel (bd_info, boot arguments, eventually
1591 initrd image) must be put below this limit.
1593 - CFG_MAX_FLASH_BANKS:
1594 Max number of Flash memory banks
1596 - CFG_MAX_FLASH_SECT:
1597 Max number of sectors on a Flash chip
1599 - CFG_FLASH_ERASE_TOUT:
1600 Timeout for Flash erase operations (in ms)
1602 - CFG_FLASH_WRITE_TOUT:
1603 Timeout for Flash write operations (in ms)
1605 - CFG_FLASH_LOCK_TOUT
1606 Timeout for Flash set sector lock bit operation (in ms)
1608 - CFG_FLASH_UNLOCK_TOUT
1609 Timeout for Flash clear lock bits operation (in ms)
1611 - CFG_FLASH_PROTECTION
1612 If defined, hardware flash sectors protection is used
1613 instead of U-Boot software protection.
1615 - CFG_DIRECT_FLASH_TFTP:
1617 Enable TFTP transfers directly to flash memory;
1618 without this option such a download has to be
1619 performed in two steps: (1) download to RAM, and (2)
1620 copy from RAM to flash.
1622 The two-step approach is usually more reliable, since
1623 you can check if the download worked before you erase
1624 the flash, but in some situations (when sytem RAM is
1625 too limited to allow for a tempory copy of the
1626 downloaded image) this option may be very useful.
1629 Define if the flash driver uses extra elements in the
1630 common flash structure for storing flash geometry
1632 - CFG_RX_ETH_BUFFER:
1633 Defines the number of ethernet receive buffers. On some
1634 ethernet controllers it is recommended to set this value
1635 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1636 buffers can be full shortly after enabling the interface
1637 on high ethernet traffic.
1638 Defaults to 4 if not defined.
1640 The following definitions that deal with the placement and management
1641 of environment data (variable area); in general, we support the
1642 following configurations:
1644 - CFG_ENV_IS_IN_FLASH:
1646 Define this if the environment is in flash memory.
1648 a) The environment occupies one whole flash sector, which is
1649 "embedded" in the text segment with the U-Boot code. This
1650 happens usually with "bottom boot sector" or "top boot
1651 sector" type flash chips, which have several smaller
1652 sectors at the start or the end. For instance, such a
1653 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1654 such a case you would place the environment in one of the
1655 4 kB sectors - with U-Boot code before and after it. With
1656 "top boot sector" type flash chips, you would put the
1657 environment in one of the last sectors, leaving a gap
1658 between U-Boot and the environment.
1662 Offset of environment data (variable area) to the
1663 beginning of flash memory; for instance, with bottom boot
1664 type flash chips the second sector can be used: the offset
1665 for this sector is given here.
1667 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1671 This is just another way to specify the start address of
1672 the flash sector containing the environment (instead of
1675 - CFG_ENV_SECT_SIZE:
1677 Size of the sector containing the environment.
1680 b) Sometimes flash chips have few, equal sized, BIG sectors.
1681 In such a case you don't want to spend a whole sector for
1686 If you use this in combination with CFG_ENV_IS_IN_FLASH
1687 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1688 of this flash sector for the environment. This saves
1689 memory for the RAM copy of the environment.
1691 It may also save flash memory if you decide to use this
1692 when your environment is "embedded" within U-Boot code,
1693 since then the remainder of the flash sector could be used
1694 for U-Boot code. It should be pointed out that this is
1695 STRONGLY DISCOURAGED from a robustness point of view:
1696 updating the environment in flash makes it always
1697 necessary to erase the WHOLE sector. If something goes
1698 wrong before the contents has been restored from a copy in
1699 RAM, your target system will be dead.
1701 - CFG_ENV_ADDR_REDUND
1704 These settings describe a second storage area used to hold
1705 a redundand copy of the environment data, so that there is
1706 a valid backup copy in case there is a power failure during
1707 a "saveenv" operation.
1709 BE CAREFUL! Any changes to the flash layout, and some changes to the
1710 source code will make it necessary to adapt <board>/u-boot.lds*
1714 - CFG_ENV_IS_IN_NVRAM:
1716 Define this if you have some non-volatile memory device
1717 (NVRAM, battery buffered SRAM) which you want to use for the
1723 These two #defines are used to determin the memory area you
1724 want to use for environment. It is assumed that this memory
1725 can just be read and written to, without any special
1728 BE CAREFUL! The first access to the environment happens quite early
1729 in U-Boot initalization (when we try to get the setting of for the
1730 console baudrate). You *MUST* have mappend your NVRAM area then, or
1733 Please note that even with NVRAM we still use a copy of the
1734 environment in RAM: we could work on NVRAM directly, but we want to
1735 keep settings there always unmodified except somebody uses "saveenv"
1736 to save the current settings.
1739 - CFG_ENV_IS_IN_EEPROM:
1741 Use this if you have an EEPROM or similar serial access
1742 device and a driver for it.
1747 These two #defines specify the offset and size of the
1748 environment area within the total memory of your EEPROM.
1750 - CFG_I2C_EEPROM_ADDR:
1751 If defined, specified the chip address of the EEPROM device.
1752 The default address is zero.
1754 - CFG_EEPROM_PAGE_WRITE_BITS:
1755 If defined, the number of bits used to address bytes in a
1756 single page in the EEPROM device. A 64 byte page, for example
1757 would require six bits.
1759 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1760 If defined, the number of milliseconds to delay between
1761 page writes. The default is zero milliseconds.
1763 - CFG_I2C_EEPROM_ADDR_LEN:
1764 The length in bytes of the EEPROM memory array address. Note
1765 that this is NOT the chip address length!
1768 The size in bytes of the EEPROM device.
1771 - CFG_ENV_IS_IN_DATAFLASH:
1773 Define this if you have a DataFlash memory device which you
1774 want to use for the environment.
1780 These three #defines specify the offset and size of the
1781 environment area within the total memory of your DataFlash placed
1782 at the specified address.
1785 - CFG_SPI_INIT_OFFSET
1787 Defines offset to the initial SPI buffer area in DPRAM. The
1788 area is used at an early stage (ROM part) if the environment
1789 is configured to reside in the SPI EEPROM: We need a 520 byte
1790 scratch DPRAM area. It is used between the two initialization
1791 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1792 to be a good choice since it makes it far enough from the
1793 start of the data area as well as from the stack pointer.
1795 Please note that the environment is read-only as long as the monitor
1796 has been relocated to RAM and a RAM copy of the environment has been
1797 created; also, when using EEPROM you will have to use getenv_r()
1798 until then to read environment variables.
1800 The environment is protected by a CRC32 checksum. Before the monitor
1801 is relocated into RAM, as a result of a bad CRC you will be working
1802 with the compiled-in default environment - *silently*!!! [This is
1803 necessary, because the first environment variable we need is the
1804 "baudrate" setting for the console - if we have a bad CRC, we don't
1805 have any device yet where we could complain.]
1807 Note: once the monitor has been relocated, then it will complain if
1808 the default environment is used; a new CRC is computed as soon as you
1809 use the "saveenv" command to store a valid environment.
1811 - CFG_FAULT_ECHO_LINK_DOWN:
1812 Echo the inverted Ethernet link state to the fault LED.
1814 Note: If this option is active, then CFG_FAULT_MII_ADDR
1815 also needs to be defined.
1817 - CFG_FAULT_MII_ADDR:
1818 MII address of the PHY to check for the Ethernet link state.
1820 Low Level (hardware related) configuration options:
1821 ---------------------------------------------------
1823 - CFG_CACHELINE_SIZE:
1824 Cache Line Size of the CPU.
1827 Default address of the IMMR after system reset.
1829 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1830 and RPXsuper) to be able to adjust the position of
1831 the IMMR register after a reset.
1833 - Floppy Disk Support:
1834 CFG_FDC_DRIVE_NUMBER
1836 the default drive number (default value 0)
1840 defines the spacing between fdc chipset registers
1845 defines the offset of register from address. It
1846 depends on which part of the data bus is connected to
1847 the fdc chipset. (default value 0)
1849 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1850 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1853 if CFG_FDC_HW_INIT is defined, then the function
1854 fdc_hw_init() is called at the beginning of the FDC
1855 setup. fdc_hw_init() must be provided by the board
1856 source code. It is used to make hardware dependant
1859 - CFG_IMMR: Physical address of the Internal Memory Mapped
1860 Register; DO NOT CHANGE! (11-4)
1861 [MPC8xx systems only]
1863 - CFG_INIT_RAM_ADDR:
1865 Start address of memory area that can be used for
1866 initial data and stack; please note that this must be
1867 writable memory that is working WITHOUT special
1868 initialization, i. e. you CANNOT use normal RAM which
1869 will become available only after programming the
1870 memory controller and running certain initialization
1873 U-Boot uses the following memory types:
1874 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1875 - MPC824X: data cache
1876 - PPC4xx: data cache
1878 - CFG_GBL_DATA_OFFSET:
1880 Offset of the initial data structure in the memory
1881 area defined by CFG_INIT_RAM_ADDR. Usually
1882 CFG_GBL_DATA_OFFSET is chosen such that the initial
1883 data is located at the end of the available space
1884 (sometimes written as (CFG_INIT_RAM_END -
1885 CFG_INIT_DATA_SIZE), and the initial stack is just
1886 below that area (growing from (CFG_INIT_RAM_ADDR +
1887 CFG_GBL_DATA_OFFSET) downward.
1890 On the MPC824X (or other systems that use the data
1891 cache for initial memory) the address chosen for
1892 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1893 point to an otherwise UNUSED address space between
1894 the top of RAM and the start of the PCI space.
1896 - CFG_SIUMCR: SIU Module Configuration (11-6)
1898 - CFG_SYPCR: System Protection Control (11-9)
1900 - CFG_TBSCR: Time Base Status and Control (11-26)
1902 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1904 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1906 - CFG_SCCR: System Clock and reset Control Register (15-27)
1908 - CFG_OR_TIMING_SDRAM:
1912 periodic timer for refresh
1914 - CFG_DER: Debug Event Register (37-47)
1916 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1917 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1918 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1920 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1922 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1923 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1924 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1925 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1927 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1928 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1929 Machine Mode Register and Memory Periodic Timer
1930 Prescaler definitions (SDRAM timing)
1932 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1933 enable I2C microcode relocation patch (MPC8xx);
1934 define relocation offset in DPRAM [DSP2]
1936 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1937 enable SPI microcode relocation patch (MPC8xx);
1938 define relocation offset in DPRAM [SCC4]
1941 Use OSCM clock mode on MBX8xx board. Be careful,
1942 wrong setting might damage your board. Read
1943 doc/README.MBX before setting this variable!
1945 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1946 Offset of the bootmode word in DPRAM used by post
1947 (Power On Self Tests). This definition overrides
1948 #define'd default value in commproc.h resp.
1951 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
1952 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
1953 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
1954 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
1955 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
1956 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
1957 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
1958 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
1959 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
1961 Building the Software:
1962 ======================
1964 Building U-Boot has been tested in native PPC environments (on a
1965 PowerBook G3 running LinuxPPC 2000) and in cross environments
1966 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
1969 If you are not using a native PPC environment, it is assumed that you
1970 have the GNU cross compiling tools available in your path and named
1971 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
1972 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
1973 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
1976 CROSS_COMPILE = ppc_4xx-
1979 U-Boot is intended to be simple to build. After installing the
1980 sources you must configure U-Boot for one specific board type. This
1985 where "NAME_config" is the name of one of the existing
1986 configurations; the following names are supported:
1988 ADCIOP_config GTH_config TQM850L_config
1989 ADS860_config IP860_config TQM855L_config
1990 AR405_config IVML24_config TQM860L_config
1991 CANBT_config IVMS8_config WALNUT405_config
1992 CPCI405_config LANTEC_config cogent_common_config
1993 CPCIISER4_config MBX_config cogent_mpc8260_config
1994 CU824_config MBX860T_config cogent_mpc8xx_config
1995 ESTEEM192E_config RPXlite_config hermes_config
1996 ETX094_config RPXsuper_config hymod_config
1997 FADS823_config SM850_config lwmon_config
1998 FADS850SAR_config SPD823TS_config pcu_e_config
1999 FADS860T_config SXNI855T_config rsdproto_config
2000 FPS850L_config Sandpoint8240_config sbc8260_config
2001 GENIETV_config TQM823L_config PIP405_config
2002 GEN860T_config EBONY_config FPS860L_config
2003 ELPT860_config cmi_mpc5xx_config NETVIA_config
2004 at91rm9200dk_config omap1510inn_config MPC8260ADS_config
2005 omap1610inn_config ZPC1900_config MPC8540ADS_config
2006 MPC8560ADS_config QS850_config QS823_config
2007 QS860T_config DUET_ADS_config
2009 Note: for some board special configuration names may exist; check if
2010 additional information is available from the board vendor; for
2011 instance, the TQM8xxL systems run normally at 50 MHz and use a
2012 SCC for 10baseT ethernet; there are also systems with 80 MHz
2013 CPU clock, and an optional Fast Ethernet module is available
2014 for CPU's with FEC. You can select such additional "features"
2015 when chosing the configuration, i. e.
2018 - will configure for a plain TQM860L, i. e. 50MHz, no FEC
2020 make TQM860L_FEC_config
2021 - will configure for a TQM860L at 50MHz with FEC for ethernet
2023 make TQM860L_80MHz_config
2024 - will configure for a TQM860L at 80 MHz, with normal 10baseT
2027 make TQM860L_FEC_80MHz_config
2028 - will configure for a TQM860L at 80 MHz with FEC for ethernet
2030 make TQM823L_LCD_config
2031 - will configure for a TQM823L with U-Boot console on LCD
2033 make TQM823L_LCD_80MHz_config
2034 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD
2039 Finally, type "make all", and you should get some working U-Boot
2040 images ready for download to / installation on your system:
2042 - "u-boot.bin" is a raw binary image
2043 - "u-boot" is an image in ELF binary format
2044 - "u-boot.srec" is in Motorola S-Record format
2047 Please be aware that the Makefiles assume you are using GNU make, so
2048 for instance on NetBSD you might need to use "gmake" instead of
2052 If the system board that you have is not listed, then you will need
2053 to port U-Boot to your hardware platform. To do this, follow these
2056 1. Add a new configuration option for your board to the toplevel
2057 "Makefile" and to the "MAKEALL" script, using the existing
2058 entries as examples. Note that here and at many other places
2059 boards and other names are listed in alphabetical sort order. Please
2061 2. Create a new directory to hold your board specific code. Add any
2062 files you need. In your board directory, you will need at least
2063 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2064 3. Create a new configuration file "include/configs/<board>.h" for
2066 3. If you're porting U-Boot to a new CPU, then also create a new
2067 directory to hold your CPU specific code. Add any files you need.
2068 4. Run "make <board>_config" with your new name.
2069 5. Type "make", and you should get a working "u-boot.srec" file
2070 to be installed on your target system.
2071 6. Debug and solve any problems that might arise.
2072 [Of course, this last step is much harder than it sounds.]
2075 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2076 ==============================================================
2078 If you have modified U-Boot sources (for instance added a new board
2079 or support for new devices, a new CPU, etc.) you are expected to
2080 provide feedback to the other developers. The feedback normally takes
2081 the form of a "patch", i. e. a context diff against a certain (latest
2082 official or latest in CVS) version of U-Boot sources.
2084 But before you submit such a patch, please verify that your modifi-
2085 cation did not break existing code. At least make sure that *ALL* of
2086 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2087 just run the "MAKEALL" script, which will configure and build U-Boot
2088 for ALL supported system. Be warned, this will take a while. You can
2089 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2090 environment variable to the script, i. e. to use the cross tools from
2091 MontaVista's Hard Hat Linux you can type
2093 CROSS_COMPILE=ppc_8xx- MAKEALL
2095 or to build on a native PowerPC system you can type
2097 CROSS_COMPILE=' ' MAKEALL
2099 See also "U-Boot Porting Guide" below.
2102 Monitor Commands - Overview:
2103 ============================
2105 go - start application at address 'addr'
2106 run - run commands in an environment variable
2107 bootm - boot application image from memory
2108 bootp - boot image via network using BootP/TFTP protocol
2109 tftpboot- boot image via network using TFTP protocol
2110 and env variables "ipaddr" and "serverip"
2111 (and eventually "gatewayip")
2112 rarpboot- boot image via network using RARP/TFTP protocol
2113 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2114 loads - load S-Record file over serial line
2115 loadb - load binary file over serial line (kermit mode)
2117 mm - memory modify (auto-incrementing)
2118 nm - memory modify (constant address)
2119 mw - memory write (fill)
2121 cmp - memory compare
2122 crc32 - checksum calculation
2123 imd - i2c memory display
2124 imm - i2c memory modify (auto-incrementing)
2125 inm - i2c memory modify (constant address)
2126 imw - i2c memory write (fill)
2127 icrc32 - i2c checksum calculation
2128 iprobe - probe to discover valid I2C chip addresses
2129 iloop - infinite loop on address range
2130 isdram - print SDRAM configuration information
2131 sspi - SPI utility commands
2132 base - print or set address offset
2133 printenv- print environment variables
2134 setenv - set environment variables
2135 saveenv - save environment variables to persistent storage
2136 protect - enable or disable FLASH write protection
2137 erase - erase FLASH memory
2138 flinfo - print FLASH memory information
2139 bdinfo - print Board Info structure
2140 iminfo - print header information for application image
2141 coninfo - print console devices and informations
2142 ide - IDE sub-system
2143 loop - infinite loop on address range
2144 mtest - simple RAM test
2145 icache - enable or disable instruction cache
2146 dcache - enable or disable data cache
2147 reset - Perform RESET of the CPU
2148 echo - echo args to console
2149 version - print monitor version
2150 help - print online help
2151 ? - alias for 'help'
2154 Monitor Commands - Detailed Description:
2155 ========================================
2159 For now: just type "help <command>".
2162 Environment Variables:
2163 ======================
2165 U-Boot supports user configuration using Environment Variables which
2166 can be made persistent by saving to Flash memory.
2168 Environment Variables are set using "setenv", printed using
2169 "printenv", and saved to Flash using "saveenv". Using "setenv"
2170 without a value can be used to delete a variable from the
2171 environment. As long as you don't save the environment you are
2172 working with an in-memory copy. In case the Flash area containing the
2173 environment is erased by accident, a default environment is provided.
2175 Some configuration options can be set using Environment Variables:
2177 baudrate - see CONFIG_BAUDRATE
2179 bootdelay - see CONFIG_BOOTDELAY
2181 bootcmd - see CONFIG_BOOTCOMMAND
2183 bootargs - Boot arguments when booting an RTOS image
2185 bootfile - Name of the image to load with TFTP
2187 autoload - if set to "no" (any string beginning with 'n'),
2188 "bootp" will just load perform a lookup of the
2189 configuration from the BOOTP server, but not try to
2190 load any image using TFTP
2192 autostart - if set to "yes", an image loaded using the "bootp",
2193 "rarpboot", "tftpboot" or "diskboot" commands will
2194 be automatically started (by internally calling
2197 If set to "no", a standalone image passed to the
2198 "bootm" command will be copied to the load address
2199 (and eventually uncompressed), but NOT be started.
2200 This can be used to load and uncompress arbitrary
2203 initrd_high - restrict positioning of initrd images:
2204 If this variable is not set, initrd images will be
2205 copied to the highest possible address in RAM; this
2206 is usually what you want since it allows for
2207 maximum initrd size. If for some reason you want to
2208 make sure that the initrd image is loaded below the
2209 CFG_BOOTMAPSZ limit, you can set this environment
2210 variable to a value of "no" or "off" or "0".
2211 Alternatively, you can set it to a maximum upper
2212 address to use (U-Boot will still check that it
2213 does not overwrite the U-Boot stack and data).
2215 For instance, when you have a system with 16 MB
2216 RAM, and want to reserve 4 MB from use by Linux,
2217 you can do this by adding "mem=12M" to the value of
2218 the "bootargs" variable. However, now you must make
2219 sure that the initrd image is placed in the first
2220 12 MB as well - this can be done with
2222 setenv initrd_high 00c00000
2224 If you set initrd_high to 0xFFFFFFFF, this is an
2225 indication to U-Boot that all addresses are legal
2226 for the Linux kernel, including addresses in flash
2227 memory. In this case U-Boot will NOT COPY the
2228 ramdisk at all. This may be useful to reduce the
2229 boot time on your system, but requires that this
2230 feature is supported by your Linux kernel.
2232 ipaddr - IP address; needed for tftpboot command
2234 loadaddr - Default load address for commands like "bootp",
2235 "rarpboot", "tftpboot", "loadb" or "diskboot"
2237 loads_echo - see CONFIG_LOADS_ECHO
2239 serverip - TFTP server IP address; needed for tftpboot command
2241 bootretry - see CONFIG_BOOT_RETRY_TIME
2243 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2245 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2248 The following environment variables may be used and automatically
2249 updated by the network boot commands ("bootp" and "rarpboot"),
2250 depending the information provided by your boot server:
2252 bootfile - see above
2253 dnsip - IP address of your Domain Name Server
2254 dnsip2 - IP address of your secondary Domain Name Server
2255 gatewayip - IP address of the Gateway (Router) to use
2256 hostname - Target hostname
2258 netmask - Subnet Mask
2259 rootpath - Pathname of the root filesystem on the NFS server
2260 serverip - see above
2263 There are two special Environment Variables:
2265 serial# - contains hardware identification information such
2266 as type string and/or serial number
2267 ethaddr - Ethernet address
2269 These variables can be set only once (usually during manufacturing of
2270 the board). U-Boot refuses to delete or overwrite these variables
2271 once they have been set once.
2274 Further special Environment Variables:
2276 ver - Contains the U-Boot version string as printed
2277 with the "version" command. This variable is
2278 readonly (see CONFIG_VERSION_VARIABLE).
2281 Please note that changes to some configuration parameters may take
2282 only effect after the next boot (yes, that's just like Windoze :-).
2285 Command Line Parsing:
2286 =====================
2288 There are two different command line parsers available with U-Boot:
2289 the old "simple" one, and the much more powerful "hush" shell:
2291 Old, simple command line parser:
2292 --------------------------------
2294 - supports environment variables (through setenv / saveenv commands)
2295 - several commands on one line, separated by ';'
2296 - variable substitution using "... $(name) ..." syntax
2297 - special characters ('$', ';') can be escaped by prefixing with '\',
2299 setenv bootcmd bootm \$(address)
2300 - You can also escape text by enclosing in single apostrophes, for example:
2301 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2306 - similar to Bourne shell, with control structures like
2307 if...then...else...fi, for...do...done; while...do...done,
2308 until...do...done, ...
2309 - supports environment ("global") variables (through setenv / saveenv
2310 commands) and local shell variables (through standard shell syntax
2311 "name=value"); only environment variables can be used with "run"
2317 (1) If a command line (or an environment variable executed by a "run"
2318 command) contains several commands separated by semicolon, and
2319 one of these commands fails, then the remaining commands will be
2322 (2) If you execute several variables with one call to run (i. e.
2323 calling run with a list af variables as arguments), any failing
2324 command will cause "run" to terminate, i. e. the remaining
2325 variables are not executed.
2327 Note for Redundant Ethernet Interfaces:
2328 =======================================
2330 Some boards come with redundant ethernet interfaces; U-Boot supports
2331 such configurations and is capable of automatic selection of a
2332 "working" interface when needed. MAC assignment works as follows:
2334 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2335 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2336 "eth1addr" (=>eth1), "eth2addr", ...
2338 If the network interface stores some valid MAC address (for instance
2339 in SROM), this is used as default address if there is NO correspon-
2340 ding setting in the environment; if the corresponding environment
2341 variable is set, this overrides the settings in the card; that means:
2343 o If the SROM has a valid MAC address, and there is no address in the
2344 environment, the SROM's address is used.
2346 o If there is no valid address in the SROM, and a definition in the
2347 environment exists, then the value from the environment variable is
2350 o If both the SROM and the environment contain a MAC address, and
2351 both addresses are the same, this MAC address is used.
2353 o If both the SROM and the environment contain a MAC address, and the
2354 addresses differ, the value from the environment is used and a
2357 o If neither SROM nor the environment contain a MAC address, an error
2364 The "boot" commands of this monitor operate on "image" files which
2365 can be basicly anything, preceeded by a special header; see the
2366 definitions in include/image.h for details; basicly, the header
2367 defines the following image properties:
2369 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2370 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2371 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2372 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2373 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2374 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2375 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2376 * Compression Type (uncompressed, gzip, bzip2)
2382 The header is marked by a special Magic Number, and both the header
2383 and the data portions of the image are secured against corruption by
2390 Although U-Boot should support any OS or standalone application
2391 easily, the main focus has always been on Linux during the design of
2394 U-Boot includes many features that so far have been part of some
2395 special "boot loader" code within the Linux kernel. Also, any
2396 "initrd" images to be used are no longer part of one big Linux image;
2397 instead, kernel and "initrd" are separate images. This implementation
2398 serves several purposes:
2400 - the same features can be used for other OS or standalone
2401 applications (for instance: using compressed images to reduce the
2402 Flash memory footprint)
2404 - it becomes much easier to port new Linux kernel versions because
2405 lots of low-level, hardware dependent stuff are done by U-Boot
2407 - the same Linux kernel image can now be used with different "initrd"
2408 images; of course this also means that different kernel images can
2409 be run with the same "initrd". This makes testing easier (you don't
2410 have to build a new "zImage.initrd" Linux image when you just
2411 change a file in your "initrd"). Also, a field-upgrade of the
2412 software is easier now.
2418 Porting Linux to U-Boot based systems:
2419 ---------------------------------------
2421 U-Boot cannot save you from doing all the necessary modifications to
2422 configure the Linux device drivers for use with your target hardware
2423 (no, we don't intend to provide a full virtual machine interface to
2426 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2428 Just make sure your machine specific header file (for instance
2429 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2430 Information structure as we define in include/u-boot.h, and make
2431 sure that your definition of IMAP_ADDR uses the same value as your
2432 U-Boot configuration in CFG_IMMR.
2435 Configuring the Linux kernel:
2436 -----------------------------
2438 No specific requirements for U-Boot. Make sure you have some root
2439 device (initial ramdisk, NFS) for your target system.
2442 Building a Linux Image:
2443 -----------------------
2445 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2446 not used. If you use recent kernel source, a new build target
2447 "uImage" will exist which automatically builds an image usable by
2448 U-Boot. Most older kernels also have support for a "pImage" target,
2449 which was introduced for our predecessor project PPCBoot and uses a
2450 100% compatible format.
2459 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2460 encapsulate a compressed Linux kernel image with header information,
2461 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2463 * build a standard "vmlinux" kernel image (in ELF binary format):
2465 * convert the kernel into a raw binary image:
2467 ${CROSS_COMPILE}-objcopy -O binary \
2468 -R .note -R .comment \
2469 -S vmlinux linux.bin
2471 * compress the binary image:
2475 * package compressed binary image for U-Boot:
2477 mkimage -A ppc -O linux -T kernel -C gzip \
2478 -a 0 -e 0 -n "Linux Kernel Image" \
2479 -d linux.bin.gz uImage
2482 The "mkimage" tool can also be used to create ramdisk images for use
2483 with U-Boot, either separated from the Linux kernel image, or
2484 combined into one file. "mkimage" encapsulates the images with a 64
2485 byte header containing information about target architecture,
2486 operating system, image type, compression method, entry points, time
2487 stamp, CRC32 checksums, etc.
2489 "mkimage" can be called in two ways: to verify existing images and
2490 print the header information, or to build new images.
2492 In the first form (with "-l" option) mkimage lists the information
2493 contained in the header of an existing U-Boot image; this includes
2494 checksum verification:
2496 tools/mkimage -l image
2497 -l ==> list image header information
2499 The second form (with "-d" option) is used to build a U-Boot image
2500 from a "data file" which is used as image payload:
2502 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2503 -n name -d data_file image
2504 -A ==> set architecture to 'arch'
2505 -O ==> set operating system to 'os'
2506 -T ==> set image type to 'type'
2507 -C ==> set compression type 'comp'
2508 -a ==> set load address to 'addr' (hex)
2509 -e ==> set entry point to 'ep' (hex)
2510 -n ==> set image name to 'name'
2511 -d ==> use image data from 'datafile'
2513 Right now, all Linux kernels use the same load address (0x00000000),
2514 but the entry point address depends on the kernel version:
2516 - 2.2.x kernels have the entry point at 0x0000000C,
2517 - 2.3.x and later kernels have the entry point at 0x00000000.
2519 So a typical call to build a U-Boot image would read:
2521 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2522 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2523 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2524 > examples/uImage.TQM850L
2525 Image Name: 2.4.4 kernel for TQM850L
2526 Created: Wed Jul 19 02:34:59 2000
2527 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2528 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2529 Load Address: 0x00000000
2530 Entry Point: 0x00000000
2532 To verify the contents of the image (or check for corruption):
2534 -> tools/mkimage -l examples/uImage.TQM850L
2535 Image Name: 2.4.4 kernel for TQM850L
2536 Created: Wed Jul 19 02:34:59 2000
2537 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2538 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2539 Load Address: 0x00000000
2540 Entry Point: 0x00000000
2542 NOTE: for embedded systems where boot time is critical you can trade
2543 speed for memory and install an UNCOMPRESSED image instead: this
2544 needs more space in Flash, but boots much faster since it does not
2545 need to be uncompressed:
2547 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2548 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2549 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2550 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2551 > examples/uImage.TQM850L-uncompressed
2552 Image Name: 2.4.4 kernel for TQM850L
2553 Created: Wed Jul 19 02:34:59 2000
2554 Image Type: PowerPC Linux Kernel Image (uncompressed)
2555 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2556 Load Address: 0x00000000
2557 Entry Point: 0x00000000
2560 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2561 when your kernel is intended to use an initial ramdisk:
2563 -> tools/mkimage -n 'Simple Ramdisk Image' \
2564 > -A ppc -O linux -T ramdisk -C gzip \
2565 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2566 Image Name: Simple Ramdisk Image
2567 Created: Wed Jan 12 14:01:50 2000
2568 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2569 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2570 Load Address: 0x00000000
2571 Entry Point: 0x00000000
2574 Installing a Linux Image:
2575 -------------------------
2577 To downloading a U-Boot image over the serial (console) interface,
2578 you must convert the image to S-Record format:
2580 objcopy -I binary -O srec examples/image examples/image.srec
2582 The 'objcopy' does not understand the information in the U-Boot
2583 image header, so the resulting S-Record file will be relative to
2584 address 0x00000000. To load it to a given address, you need to
2585 specify the target address as 'offset' parameter with the 'loads'
2588 Example: install the image to address 0x40100000 (which on the
2589 TQM8xxL is in the first Flash bank):
2591 => erase 40100000 401FFFFF
2597 ## Ready for S-Record download ...
2598 ~>examples/image.srec
2599 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2601 15989 15990 15991 15992
2602 [file transfer complete]
2604 ## Start Addr = 0x00000000
2607 You can check the success of the download using the 'iminfo' command;
2608 this includes a checksum verification so you can be sure no data
2609 corruption happened:
2613 ## Checking Image at 40100000 ...
2614 Image Name: 2.2.13 for initrd on TQM850L
2615 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2616 Data Size: 335725 Bytes = 327 kB = 0 MB
2617 Load Address: 00000000
2618 Entry Point: 0000000c
2619 Verifying Checksum ... OK
2625 The "bootm" command is used to boot an application that is stored in
2626 memory (RAM or Flash). In case of a Linux kernel image, the contents
2627 of the "bootargs" environment variable is passed to the kernel as
2628 parameters. You can check and modify this variable using the
2629 "printenv" and "setenv" commands:
2632 => printenv bootargs
2633 bootargs=root=/dev/ram
2635 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2637 => printenv bootargs
2638 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2641 ## Booting Linux kernel at 40020000 ...
2642 Image Name: 2.2.13 for NFS on TQM850L
2643 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2644 Data Size: 381681 Bytes = 372 kB = 0 MB
2645 Load Address: 00000000
2646 Entry Point: 0000000c
2647 Verifying Checksum ... OK
2648 Uncompressing Kernel Image ... OK
2649 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
2650 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2651 time_init: decrementer frequency = 187500000/60
2652 Calibrating delay loop... 49.77 BogoMIPS
2653 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2656 If you want to boot a Linux kernel with initial ram disk, you pass
2657 the memory addresses of both the kernel and the initrd image (PPBCOOT
2658 format!) to the "bootm" command:
2660 => imi 40100000 40200000
2662 ## Checking Image at 40100000 ...
2663 Image Name: 2.2.13 for initrd on TQM850L
2664 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2665 Data Size: 335725 Bytes = 327 kB = 0 MB
2666 Load Address: 00000000
2667 Entry Point: 0000000c
2668 Verifying Checksum ... OK
2670 ## Checking Image at 40200000 ...
2671 Image Name: Simple Ramdisk Image
2672 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2673 Data Size: 566530 Bytes = 553 kB = 0 MB
2674 Load Address: 00000000
2675 Entry Point: 00000000
2676 Verifying Checksum ... OK
2678 => bootm 40100000 40200000
2679 ## Booting Linux kernel at 40100000 ...
2680 Image Name: 2.2.13 for initrd on TQM850L
2681 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2682 Data Size: 335725 Bytes = 327 kB = 0 MB
2683 Load Address: 00000000
2684 Entry Point: 0000000c
2685 Verifying Checksum ... OK
2686 Uncompressing Kernel Image ... OK
2687 ## Loading RAMDisk Image at 40200000 ...
2688 Image Name: Simple Ramdisk Image
2689 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2690 Data Size: 566530 Bytes = 553 kB = 0 MB
2691 Load Address: 00000000
2692 Entry Point: 00000000
2693 Verifying Checksum ... OK
2694 Loading Ramdisk ... OK
2695 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
2696 Boot arguments: root=/dev/ram
2697 time_init: decrementer frequency = 187500000/60
2698 Calibrating delay loop... 49.77 BogoMIPS
2700 RAMDISK: Compressed image found at block 0
2701 VFS: Mounted root (ext2 filesystem).
2705 More About U-Boot Image Types:
2706 ------------------------------
2708 U-Boot supports the following image types:
2710 "Standalone Programs" are directly runnable in the environment
2711 provided by U-Boot; it is expected that (if they behave
2712 well) you can continue to work in U-Boot after return from
2713 the Standalone Program.
2714 "OS Kernel Images" are usually images of some Embedded OS which
2715 will take over control completely. Usually these programs
2716 will install their own set of exception handlers, device
2717 drivers, set up the MMU, etc. - this means, that you cannot
2718 expect to re-enter U-Boot except by resetting the CPU.
2719 "RAMDisk Images" are more or less just data blocks, and their
2720 parameters (address, size) are passed to an OS kernel that is
2722 "Multi-File Images" contain several images, typically an OS
2723 (Linux) kernel image and one or more data images like
2724 RAMDisks. This construct is useful for instance when you want
2725 to boot over the network using BOOTP etc., where the boot
2726 server provides just a single image file, but you want to get
2727 for instance an OS kernel and a RAMDisk image.
2729 "Multi-File Images" start with a list of image sizes, each
2730 image size (in bytes) specified by an "uint32_t" in network
2731 byte order. This list is terminated by an "(uint32_t)0".
2732 Immediately after the terminating 0 follow the images, one by
2733 one, all aligned on "uint32_t" boundaries (size rounded up to
2734 a multiple of 4 bytes).
2736 "Firmware Images" are binary images containing firmware (like
2737 U-Boot or FPGA images) which usually will be programmed to
2740 "Script files" are command sequences that will be executed by
2741 U-Boot's command interpreter; this feature is especially
2742 useful when you configure U-Boot to use a real shell (hush)
2743 as command interpreter.
2749 One of the features of U-Boot is that you can dynamically load and
2750 run "standalone" applications, which can use some resources of
2751 U-Boot like console I/O functions or interrupt services.
2753 Two simple examples are included with the sources:
2758 'examples/hello_world.c' contains a small "Hello World" Demo
2759 application; it is automatically compiled when you build U-Boot.
2760 It's configured to run at address 0x00040004, so you can play with it
2764 ## Ready for S-Record download ...
2765 ~>examples/hello_world.srec
2766 1 2 3 4 5 6 7 8 9 10 11 ...
2767 [file transfer complete]
2769 ## Start Addr = 0x00040004
2771 => go 40004 Hello World! This is a test.
2772 ## Starting application at 0x00040004 ...
2783 Hit any key to exit ...
2785 ## Application terminated, rc = 0x0
2787 Another example, which demonstrates how to register a CPM interrupt
2788 handler with the U-Boot code, can be found in 'examples/timer.c'.
2789 Here, a CPM timer is set up to generate an interrupt every second.
2790 The interrupt service routine is trivial, just printing a '.'
2791 character, but this is just a demo program. The application can be
2792 controlled by the following keys:
2794 ? - print current values og the CPM Timer registers
2795 b - enable interrupts and start timer
2796 e - stop timer and disable interrupts
2797 q - quit application
2800 ## Ready for S-Record download ...
2801 ~>examples/timer.srec
2802 1 2 3 4 5 6 7 8 9 10 11 ...
2803 [file transfer complete]
2805 ## Start Addr = 0x00040004
2808 ## Starting application at 0x00040004 ...
2811 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2814 [q, b, e, ?] Set interval 1000000 us
2817 [q, b, e, ?] ........
2818 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2821 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2824 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2827 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2829 [q, b, e, ?] ...Stopping timer
2831 [q, b, e, ?] ## Application terminated, rc = 0x0
2837 Over time, many people have reported problems when trying to use the
2838 "minicom" terminal emulation program for serial download. I (wd)
2839 consider minicom to be broken, and recommend not to use it. Under
2840 Unix, I recommend to use C-Kermit for general purpose use (and
2841 especially for kermit binary protocol download ("loadb" command), and
2842 use "cu" for S-Record download ("loads" command).
2844 Nevertheless, if you absolutely want to use it try adding this
2845 configuration to your "File transfer protocols" section:
2847 Name Program Name U/D FullScr IO-Red. Multi
2848 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2849 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
2855 Starting at version 0.9.2, U-Boot supports NetBSD both as host
2856 (build U-Boot) and target system (boots NetBSD/mpc8xx).
2858 Building requires a cross environment; it is known to work on
2859 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2860 need gmake since the Makefiles are not compatible with BSD make).
2861 Note that the cross-powerpc package does not install include files;
2862 attempting to build U-Boot will fail because <machine/ansi.h> is
2863 missing. This file has to be installed and patched manually:
2865 # cd /usr/pkg/cross/powerpc-netbsd/include
2867 # ln -s powerpc machine
2868 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2869 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2871 Native builds *don't* work due to incompatibilities between native
2872 and U-Boot include files.
2874 Booting assumes that (the first part of) the image booted is a
2875 stage-2 loader which in turn loads and then invokes the kernel
2876 proper. Loader sources will eventually appear in the NetBSD source
2877 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2878 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2882 Implementation Internals:
2883 =========================
2885 The following is not intended to be a complete description of every
2886 implementation detail. However, it should help to understand the
2887 inner workings of U-Boot and make it easier to port it to custom
2891 Initial Stack, Global Data:
2892 ---------------------------
2894 The implementation of U-Boot is complicated by the fact that U-Boot
2895 starts running out of ROM (flash memory), usually without access to
2896 system RAM (because the memory controller is not initialized yet).
2897 This means that we don't have writable Data or BSS segments, and BSS
2898 is not initialized as zero. To be able to get a C environment working
2899 at all, we have to allocate at least a minimal stack. Implementation
2900 options for this are defined and restricted by the CPU used: Some CPU
2901 models provide on-chip memory (like the IMMR area on MPC8xx and
2902 MPC826x processors), on others (parts of) the data cache can be
2903 locked as (mis-) used as memory, etc.
2905 Chris Hallinan posted a good summary of these issues to the
2906 u-boot-users mailing list:
2908 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2909 From: "Chris Hallinan" <clh@net1plus.com>
2910 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2913 Correct me if I'm wrong, folks, but the way I understand it
2914 is this: Using DCACHE as initial RAM for Stack, etc, does not
2915 require any physical RAM backing up the cache. The cleverness
2916 is that the cache is being used as a temporary supply of
2917 necessary storage before the SDRAM controller is setup. It's
2918 beyond the scope of this list to expain the details, but you
2919 can see how this works by studying the cache architecture and
2920 operation in the architecture and processor-specific manuals.
2922 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2923 is another option for the system designer to use as an
2924 initial stack/ram area prior to SDRAM being available. Either
2925 option should work for you. Using CS 4 should be fine if your
2926 board designers haven't used it for something that would
2927 cause you grief during the initial boot! It is frequently not
2930 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
2931 with your processor/board/system design. The default value
2932 you will find in any recent u-boot distribution in
2933 Walnut405.h should work for you. I'd set it to a value larger
2934 than your SDRAM module. If you have a 64MB SDRAM module, set
2935 it above 400_0000. Just make sure your board has no resources
2936 that are supposed to respond to that address! That code in
2937 start.S has been around a while and should work as is when
2938 you get the config right.
2943 It is essential to remember this, since it has some impact on the C
2944 code for the initialization procedures:
2946 * Initialized global data (data segment) is read-only. Do not attempt
2949 * Do not use any unitialized global data (or implicitely initialized
2950 as zero data - BSS segment) at all - this is undefined, initiali-
2951 zation is performed later (when relocating to RAM).
2953 * Stack space is very limited. Avoid big data buffers or things like
2956 Having only the stack as writable memory limits means we cannot use
2957 normal global data to share information beween the code. But it
2958 turned out that the implementation of U-Boot can be greatly
2959 simplified by making a global data structure (gd_t) available to all
2960 functions. We could pass a pointer to this data as argument to _all_
2961 functions, but this would bloat the code. Instead we use a feature of
2962 the GCC compiler (Global Register Variables) to share the data: we
2963 place a pointer (gd) to the global data into a register which we
2964 reserve for this purpose.
2966 When choosing a register for such a purpose we are restricted by the
2967 relevant (E)ABI specifications for the current architecture, and by
2968 GCC's implementation.
2970 For PowerPC, the following registers have specific use:
2973 R3-R4: parameter passing and return values
2974 R5-R10: parameter passing
2975 R13: small data area pointer
2979 (U-Boot also uses R14 as internal GOT pointer.)
2981 ==> U-Boot will use R29 to hold a pointer to the global data
2983 Note: on PPC, we could use a static initializer (since the
2984 address of the global data structure is known at compile time),
2985 but it turned out that reserving a register results in somewhat
2986 smaller code - although the code savings are not that big (on
2987 average for all boards 752 bytes for the whole U-Boot image,
2988 624 text + 127 data).
2990 On ARM, the following registers are used:
2992 R0: function argument word/integer result
2993 R1-R3: function argument word
2995 R10: stack limit (used only if stack checking if enabled)
2996 R11: argument (frame) pointer
2997 R12: temporary workspace
3000 R15: program counter
3002 ==> U-Boot will use R8 to hold a pointer to the global data
3008 U-Boot runs in system state and uses physical addresses, i.e. the
3009 MMU is not used either for address mapping nor for memory protection.
3011 The available memory is mapped to fixed addresses using the memory
3012 controller. In this process, a contiguous block is formed for each
3013 memory type (Flash, SDRAM, SRAM), even when it consists of several
3014 physical memory banks.
3016 U-Boot is installed in the first 128 kB of the first Flash bank (on
3017 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3018 booting and sizing and initializing DRAM, the code relocates itself
3019 to the upper end of DRAM. Immediately below the U-Boot code some
3020 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3021 configuration setting]. Below that, a structure with global Board
3022 Info data is placed, followed by the stack (growing downward).
3024 Additionally, some exception handler code is copied to the low 8 kB
3025 of DRAM (0x00000000 ... 0x00001FFF).
3027 So a typical memory configuration with 16 MB of DRAM could look like
3030 0x0000 0000 Exception Vector code
3033 0x0000 2000 Free for Application Use
3039 0x00FB FF20 Monitor Stack (Growing downward)
3040 0x00FB FFAC Board Info Data and permanent copy of global data
3041 0x00FC 0000 Malloc Arena
3044 0x00FE 0000 RAM Copy of Monitor Code
3045 ... eventually: LCD or video framebuffer
3046 ... eventually: pRAM (Protected RAM - unchanged by reset)
3047 0x00FF FFFF [End of RAM]
3050 System Initialization:
3051 ----------------------
3053 In the reset configuration, U-Boot starts at the reset entry point
3054 (on most PowerPC systens at address 0x00000100). Because of the reset
3055 configuration for CS0# this is a mirror of the onboard Flash memory.
3056 To be able to re-map memory U-Boot then jumps to its link address.
3057 To be able to implement the initialization code in C, a (small!)
3058 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3059 which provide such a feature like MPC8xx or MPC8260), or in a locked
3060 part of the data cache. After that, U-Boot initializes the CPU core,
3061 the caches and the SIU.
3063 Next, all (potentially) available memory banks are mapped using a
3064 preliminary mapping. For example, we put them on 512 MB boundaries
3065 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3066 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3067 programmed for SDRAM access. Using the temporary configuration, a
3068 simple memory test is run that determines the size of the SDRAM
3071 When there is more than one SDRAM bank, and the banks are of
3072 different size, the largest is mapped first. For equal size, the first
3073 bank (CS2#) is mapped first. The first mapping is always for address
3074 0x00000000, with any additional banks following immediately to create
3075 contiguous memory starting from 0.
3077 Then, the monitor installs itself at the upper end of the SDRAM area
3078 and allocates memory for use by malloc() and for the global Board
3079 Info data; also, the exception vector code is copied to the low RAM
3080 pages, and the final stack is set up.
3082 Only after this relocation will you have a "normal" C environment;
3083 until that you are restricted in several ways, mostly because you are
3084 running from ROM, and because the code will have to be relocated to a
3088 U-Boot Porting Guide:
3089 ----------------------
3091 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3095 int main (int argc, char *argv[])
3097 sighandler_t no_more_time;
3099 signal (SIGALRM, no_more_time);
3100 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3102 if (available_money > available_manpower) {
3103 pay consultant to port U-Boot;
3107 Download latest U-Boot source;
3109 Subscribe to u-boot-users mailing list;
3112 email ("Hi, I am new to U-Boot, how do I get started?");
3116 Read the README file in the top level directory;
3117 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3118 Read the source, Luke;
3121 if (available_money > toLocalCurrency ($2500)) {
3124 Add a lot of aggravation and time;
3127 Create your own board support subdirectory;
3129 Create your own board config file;
3133 Add / modify source code;
3137 email ("Hi, I am having problems...");
3139 Send patch file to Wolfgang;
3144 void no_more_time (int sig)
3153 All contributions to U-Boot should conform to the Linux kernel
3154 coding style; see the file "Documentation/CodingStyle" in your Linux
3155 kernel source directory.
3157 Please note that U-Boot is implemented in C (and to some small parts
3158 in Assembler); no C++ is used, so please do not use C++ style
3159 comments (//) in your code.
3161 Please also stick to the following formatiing rules:
3162 - remove any trailing white space
3163 - use TAB characters for indentation, not spaces
3164 - make sure NOT to use DOS '\r\n' line feeds
3165 - do not add more than 2 empty lines to source files
3166 - do not add trailing empty lines to source files
3168 Submissions which do not conform to the standards may be returned
3169 with a request to reformat the changes.
3175 Since the number of patches for U-Boot is growing, we need to
3176 establish some rules. Submissions which do not conform to these rules
3177 may be rejected, even when they contain important and valuable stuff.
3180 When you send a patch, please include the following information with
3183 * For bug fixes: a description of the bug and how your patch fixes
3184 this bug. Please try to include a way of demonstrating that the
3185 patch actually fixes something.
3187 * For new features: a description of the feature and your
3190 * A CHANGELOG entry as plaintext (separate from the patch)
3192 * For major contributions, your entry to the CREDITS file
3194 * When you add support for a new board, don't forget to add this
3195 board to the MAKEALL script, too.
3197 * If your patch adds new configuration options, don't forget to
3198 document these in the README file.
3200 * The patch itself. If you are accessing the CVS repository use "cvs
3201 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3202 version of diff does not support these options, then get the latest
3203 version of GNU diff.
3205 The current directory when running this command shall be the top
3206 level directory of the U-Boot source tree, or it's parent directory
3207 (i. e. please make sure that your patch includes sufficient
3208 directory information for the affected files).
3210 We accept patches as plain text, MIME attachments or as uuencoded
3213 * If one logical set of modifications affects or creates several
3214 files, all these changes shall be submitted in a SINGLE patch file.
3216 * Changesets that contain different, unrelated modifications shall be
3217 submitted as SEPARATE patches, one patch per changeset.
3222 * Before sending the patch, run the MAKEALL script on your patched
3223 source tree and make sure that no errors or warnings are reported
3224 for any of the boards.
3226 * Keep your modifications to the necessary minimum: A patch
3227 containing several unrelated changes or arbitrary reformats will be
3228 returned with a request to re-formatting / split it.
3230 * If you modify existing code, make sure that your new code does not
3231 add to the memory footprint of the code ;-) Small is beautiful!
3232 When adding new features, these should compile conditionally only
3233 (using #ifdef), and the resulting code with the new feature
3234 disabled must not need more memory than the old code without your
projects / platform / kernel / u-boot.git / blob