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1 #
2 # (C) Copyright 2000 - 2008
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 #
5 # See file CREDITS for list of people who contributed to this
6 # project.
7 #
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.
12 #
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.
17 #
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,
21 # MA 02111-1307 USA
22 #
23
24 Summary:
25 ========
26
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
31 code.
32
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
37
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
44
45
46 Status:
47 =======
48
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
52
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
55 maintainers.
56
57
58 Where to get help:
59 ==================
60
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot-users@lists.sourceforge.net>. There is also an archive of
64 previous traffic on the mailing list - please search the archive
65 before asking FAQ's. Please see
66 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
67
68
69 Where to get source code:
70 =========================
71
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
75
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
79 directory.
80
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
83
84
85 Where we come from:
86 ===================
87
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
90 - clean up code
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
95 * S-Record download
96 * network boot
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
102
103
104 Names and Spelling:
105 ===================
106
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
110
111 This is the README file for the U-Boot project.
112
113 File names etc. shall be based on the string "u-boot". Examples:
114
115 include/asm-ppc/u-boot.h
116
117 #include <asm/u-boot.h>
118
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
121
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
124
125
126 Versioning:
127 ===========
128
129 U-Boot uses a 3 level version number containing a version, a
130 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
131 sub-version "34", and patchlevel "4".
132
133 The patchlevel is used to indicate certain stages of development
134 between released versions, i. e. officially released versions of
135 U-Boot will always have a patchlevel of "0".
136
137
138 Directory Hierarchy:
139 ====================
140
141 - board Board dependent files
142 - common Misc architecture independent functions
143 - cpu CPU specific files
144 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
145 - arm720t Files specific to ARM 720 CPUs
146 - arm920t Files specific to ARM 920 CPUs
147 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
148 - imx Files specific to Freescale MC9328 i.MX CPUs
149 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
150 - arm925t Files specific to ARM 925 CPUs
151 - arm926ejs Files specific to ARM 926 CPUs
152 - arm1136 Files specific to ARM 1136 CPUs
153 - at32ap Files specific to Atmel AVR32 AP CPUs
154 - i386 Files specific to i386 CPUs
155 - ixp Files specific to Intel XScale IXP CPUs
156 - leon2 Files specific to Gaisler LEON2 SPARC CPU
157 - leon3 Files specific to Gaisler LEON3 SPARC CPU
158 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
159 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
160 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
161 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
162 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
163 - mips Files specific to MIPS CPUs
164 - mpc5xx Files specific to Freescale MPC5xx CPUs
165 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
166 - mpc8xx Files specific to Freescale MPC8xx CPUs
167 - mpc8220 Files specific to Freescale MPC8220 CPUs
168 - mpc824x Files specific to Freescale MPC824x CPUs
169 - mpc8260 Files specific to Freescale MPC8260 CPUs
170 - mpc85xx Files specific to Freescale MPC85xx CPUs
171 - nios Files specific to Altera NIOS CPUs
172 - nios2 Files specific to Altera Nios-II CPUs
173 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
174 - pxa Files specific to Intel XScale PXA CPUs
175 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
176 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
177 - disk Code for disk drive partition handling
178 - doc Documentation (don't expect too much)
179 - drivers Commonly used device drivers
180 - dtt Digital Thermometer and Thermostat drivers
181 - examples Example code for standalone applications, etc.
182 - include Header Files
183 - lib_arm Files generic to ARM architecture
184 - lib_avr32 Files generic to AVR32 architecture
185 - lib_generic Files generic to all architectures
186 - lib_i386 Files generic to i386 architecture
187 - lib_m68k Files generic to m68k architecture
188 - lib_mips Files generic to MIPS architecture
189 - lib_nios Files generic to NIOS architecture
190 - lib_ppc Files generic to PowerPC architecture
191 - lib_sparc Files generic to SPARC architecture
192 - libfdt Library files to support flattened device trees
193 - net Networking code
194 - post Power On Self Test
195 - rtc Real Time Clock drivers
196 - tools Tools to build S-Record or U-Boot images, etc.
197
198 Software Configuration:
199 =======================
200
201 Configuration is usually done using C preprocessor defines; the
202 rationale behind that is to avoid dead code whenever possible.
203
204 There are two classes of configuration variables:
205
206 * Configuration _OPTIONS_:
207 These are selectable by the user and have names beginning with
208 "CONFIG_".
209
210 * Configuration _SETTINGS_:
211 These depend on the hardware etc. and should not be meddled with if
212 you don't know what you're doing; they have names beginning with
213 "CFG_".
214
215 Later we will add a configuration tool - probably similar to or even
216 identical to what's used for the Linux kernel. Right now, we have to
217 do the configuration by hand, which means creating some symbolic
218 links and editing some configuration files. We use the TQM8xxL boards
219 as an example here.
220
221
222 Selection of Processor Architecture and Board Type:
223 ---------------------------------------------------
224
225 For all supported boards there are ready-to-use default
226 configurations available; just type "make <board_name>_config".
227
228 Example: For a TQM823L module type:
229
230 cd u-boot
231 make TQM823L_config
232
233 For the Cogent platform, you need to specify the CPU type as well;
234 e.g. "make cogent_mpc8xx_config". And also configure the cogent
235 directory according to the instructions in cogent/README.
236
237
238 Configuration Options:
239 ----------------------
240
241 Configuration depends on the combination of board and CPU type; all
242 such information is kept in a configuration file
243 "include/configs/<board_name>.h".
244
245 Example: For a TQM823L module, all configuration settings are in
246 "include/configs/TQM823L.h".
247
248
249 Many of the options are named exactly as the corresponding Linux
250 kernel configuration options. The intention is to make it easier to
251 build a config tool - later.
252
253
254 The following options need to be configured:
255
256 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
257
258 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
259
260 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
261 Define exactly one, e.g. CONFIG_ATSTK1002
262
263 - CPU Module Type: (if CONFIG_COGENT is defined)
264 Define exactly one of
265 CONFIG_CMA286_60_OLD
266 --- FIXME --- not tested yet:
267 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
268 CONFIG_CMA287_23, CONFIG_CMA287_50
269
270 - Motherboard Type: (if CONFIG_COGENT is defined)
271 Define exactly one of
272 CONFIG_CMA101, CONFIG_CMA102
273
274 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
275 Define one or more of
276 CONFIG_CMA302
277
278 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
279 Define one or more of
280 CONFIG_LCD_HEARTBEAT - update a character position on
281 the LCD display every second with
282 a "rotator" |\-/|\-/
283
284 - Board flavour: (if CONFIG_MPC8260ADS is defined)
285 CONFIG_ADSTYPE
286 Possible values are:
287 CFG_8260ADS - original MPC8260ADS
288 CFG_8266ADS - MPC8266ADS
289 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
290 CFG_8272ADS - MPC8272ADS
291
292 - MPC824X Family Member (if CONFIG_MPC824X is defined)
293 Define exactly one of
294 CONFIG_MPC8240, CONFIG_MPC8245
295
296 - 8xx CPU Options: (if using an MPC8xx CPU)
297 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
298 get_gclk_freq() cannot work
299 e.g. if there is no 32KHz
300 reference PIT/RTC clock
301 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
302 or XTAL/EXTAL)
303
304 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
305 CFG_8xx_CPUCLK_MIN
306 CFG_8xx_CPUCLK_MAX
307 CONFIG_8xx_CPUCLK_DEFAULT
308 See doc/README.MPC866
309
310 CFG_MEASURE_CPUCLK
311
312 Define this to measure the actual CPU clock instead
313 of relying on the correctness of the configured
314 values. Mostly useful for board bringup to make sure
315 the PLL is locked at the intended frequency. Note
316 that this requires a (stable) reference clock (32 kHz
317 RTC clock or CFG_8XX_XIN)
318
319 - Intel Monahans options:
320 CFG_MONAHANS_RUN_MODE_OSC_RATIO
321
322 Defines the Monahans run mode to oscillator
323 ratio. Valid values are 8, 16, 24, 31. The core
324 frequency is this value multiplied by 13 MHz.
325
326 CFG_MONAHANS_TURBO_RUN_MODE_RATIO
327
328 Defines the Monahans turbo mode to oscillator
329 ratio. Valid values are 1 (default if undefined) and
330 2. The core frequency as calculated above is multiplied
331 by this value.
332
333 - Linux Kernel Interface:
334 CONFIG_CLOCKS_IN_MHZ
335
336 U-Boot stores all clock information in Hz
337 internally. For binary compatibility with older Linux
338 kernels (which expect the clocks passed in the
339 bd_info data to be in MHz) the environment variable
340 "clocks_in_mhz" can be defined so that U-Boot
341 converts clock data to MHZ before passing it to the
342 Linux kernel.
343 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
344 "clocks_in_mhz=1" is automatically included in the
345 default environment.
346
347 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
348
349 When transferring memsize parameter to linux, some versions
350 expect it to be in bytes, others in MB.
351 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
352
353 CONFIG_OF_LIBFDT
354
355 New kernel versions are expecting firmware settings to be
356 passed using flattened device trees (based on open firmware
357 concepts).
358
359 CONFIG_OF_LIBFDT
360 * New libfdt-based support
361 * Adds the "fdt" command
362 * The bootm command automatically updates the fdt
363
364 OF_CPU - The proper name of the cpus node.
365 OF_SOC - The proper name of the soc node.
366 OF_TBCLK - The timebase frequency.
367 OF_STDOUT_PATH - The path to the console device
368
369 boards with QUICC Engines require OF_QE to set UCC MAC
370 addresses
371
372 CONFIG_OF_BOARD_SETUP
373
374 Board code has addition modification that it wants to make
375 to the flat device tree before handing it off to the kernel
376
377 CONFIG_OF_BOOT_CPU
378
379 This define fills in the correct boot CPU in the boot
380 param header, the default value is zero if undefined.
381
382 - Serial Ports:
383 CFG_PL010_SERIAL
384
385 Define this if you want support for Amba PrimeCell PL010 UARTs.
386
387 CFG_PL011_SERIAL
388
389 Define this if you want support for Amba PrimeCell PL011 UARTs.
390
391 CONFIG_PL011_CLOCK
392
393 If you have Amba PrimeCell PL011 UARTs, set this variable to
394 the clock speed of the UARTs.
395
396 CONFIG_PL01x_PORTS
397
398 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
399 define this to a list of base addresses for each (supported)
400 port. See e.g. include/configs/versatile.h
401
402
403 - Console Interface:
404 Depending on board, define exactly one serial port
405 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
406 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
407 console by defining CONFIG_8xx_CONS_NONE
408
409 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
410 port routines must be defined elsewhere
411 (i.e. serial_init(), serial_getc(), ...)
412
413 CONFIG_CFB_CONSOLE
414 Enables console device for a color framebuffer. Needs following
415 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
416 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
417 (default big endian)
418 VIDEO_HW_RECTFILL graphic chip supports
419 rectangle fill
420 (cf. smiLynxEM)
421 VIDEO_HW_BITBLT graphic chip supports
422 bit-blit (cf. smiLynxEM)
423 VIDEO_VISIBLE_COLS visible pixel columns
424 (cols=pitch)
425 VIDEO_VISIBLE_ROWS visible pixel rows
426 VIDEO_PIXEL_SIZE bytes per pixel
427 VIDEO_DATA_FORMAT graphic data format
428 (0-5, cf. cfb_console.c)
429 VIDEO_FB_ADRS framebuffer address
430 VIDEO_KBD_INIT_FCT keyboard int fct
431 (i.e. i8042_kbd_init())
432 VIDEO_TSTC_FCT test char fct
433 (i.e. i8042_tstc)
434 VIDEO_GETC_FCT get char fct
435 (i.e. i8042_getc)
436 CONFIG_CONSOLE_CURSOR cursor drawing on/off
437 (requires blink timer
438 cf. i8042.c)
439 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
440 CONFIG_CONSOLE_TIME display time/date info in
441 upper right corner
442 (requires CONFIG_CMD_DATE)
443 CONFIG_VIDEO_LOGO display Linux logo in
444 upper left corner
445 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
446 linux_logo.h for logo.
447 Requires CONFIG_VIDEO_LOGO
448 CONFIG_CONSOLE_EXTRA_INFO
449 additional board info beside
450 the logo
451
452 When CONFIG_CFB_CONSOLE is defined, video console is
453 default i/o. Serial console can be forced with
454 environment 'console=serial'.
455
456 When CONFIG_SILENT_CONSOLE is defined, all console
457 messages (by U-Boot and Linux!) can be silenced with
458 the "silent" environment variable. See
459 doc/README.silent for more information.
460
461 - Console Baudrate:
462 CONFIG_BAUDRATE - in bps
463 Select one of the baudrates listed in
464 CFG_BAUDRATE_TABLE, see below.
465 CFG_BRGCLK_PRESCALE, baudrate prescale
466
467 - Interrupt driven serial port input:
468 CONFIG_SERIAL_SOFTWARE_FIFO
469
470 PPC405GP only.
471 Use an interrupt handler for receiving data on the
472 serial port. It also enables using hardware handshake
473 (RTS/CTS) and UART's built-in FIFO. Set the number of
474 bytes the interrupt driven input buffer should have.
475
476 Leave undefined to disable this feature, including
477 disable the buffer and hardware handshake.
478
479 - Console UART Number:
480 CONFIG_UART1_CONSOLE
481
482 AMCC PPC4xx only.
483 If defined internal UART1 (and not UART0) is used
484 as default U-Boot console.
485
486 - Boot Delay: CONFIG_BOOTDELAY - in seconds
487 Delay before automatically booting the default image;
488 set to -1 to disable autoboot.
489
490 See doc/README.autoboot for these options that
491 work with CONFIG_BOOTDELAY. None are required.
492 CONFIG_BOOT_RETRY_TIME
493 CONFIG_BOOT_RETRY_MIN
494 CONFIG_AUTOBOOT_KEYED
495 CONFIG_AUTOBOOT_PROMPT
496 CONFIG_AUTOBOOT_DELAY_STR
497 CONFIG_AUTOBOOT_STOP_STR
498 CONFIG_AUTOBOOT_DELAY_STR2
499 CONFIG_AUTOBOOT_STOP_STR2
500 CONFIG_ZERO_BOOTDELAY_CHECK
501 CONFIG_RESET_TO_RETRY
502
503 - Autoboot Command:
504 CONFIG_BOOTCOMMAND
505 Only needed when CONFIG_BOOTDELAY is enabled;
506 define a command string that is automatically executed
507 when no character is read on the console interface
508 within "Boot Delay" after reset.
509
510 CONFIG_BOOTARGS
511 This can be used to pass arguments to the bootm
512 command. The value of CONFIG_BOOTARGS goes into the
513 environment value "bootargs".
514
515 CONFIG_RAMBOOT and CONFIG_NFSBOOT
516 The value of these goes into the environment as
517 "ramboot" and "nfsboot" respectively, and can be used
518 as a convenience, when switching between booting from
519 RAM and NFS.
520
521 - Pre-Boot Commands:
522 CONFIG_PREBOOT
523
524 When this option is #defined, the existence of the
525 environment variable "preboot" will be checked
526 immediately before starting the CONFIG_BOOTDELAY
527 countdown and/or running the auto-boot command resp.
528 entering interactive mode.
529
530 This feature is especially useful when "preboot" is
531 automatically generated or modified. For an example
532 see the LWMON board specific code: here "preboot" is
533 modified when the user holds down a certain
534 combination of keys on the (special) keyboard when
535 booting the systems
536
537 - Serial Download Echo Mode:
538 CONFIG_LOADS_ECHO
539 If defined to 1, all characters received during a
540 serial download (using the "loads" command) are
541 echoed back. This might be needed by some terminal
542 emulations (like "cu"), but may as well just take
543 time on others. This setting #define's the initial
544 value of the "loads_echo" environment variable.
545
546 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
547 CONFIG_KGDB_BAUDRATE
548 Select one of the baudrates listed in
549 CFG_BAUDRATE_TABLE, see below.
550
551 - Monitor Functions:
552 Monitor commands can be included or excluded
553 from the build by using the #include files
554 "config_cmd_all.h" and #undef'ing unwanted
555 commands, or using "config_cmd_default.h"
556 and augmenting with additional #define's
557 for wanted commands.
558
559 The default command configuration includes all commands
560 except those marked below with a "*".
561
562 CONFIG_CMD_ASKENV * ask for env variable
563 CONFIG_CMD_AUTOSCRIPT Autoscript Support
564 CONFIG_CMD_BDI bdinfo
565 CONFIG_CMD_BEDBUG * Include BedBug Debugger
566 CONFIG_CMD_BMP * BMP support
567 CONFIG_CMD_BSP * Board specific commands
568 CONFIG_CMD_BOOTD bootd
569 CONFIG_CMD_CACHE * icache, dcache
570 CONFIG_CMD_CONSOLE coninfo
571 CONFIG_CMD_DATE * support for RTC, date/time...
572 CONFIG_CMD_DHCP * DHCP support
573 CONFIG_CMD_DIAG * Diagnostics
574 CONFIG_CMD_DOC * Disk-On-Chip Support
575 CONFIG_CMD_DTT * Digital Therm and Thermostat
576 CONFIG_CMD_ECHO echo arguments
577 CONFIG_CMD_EEPROM * EEPROM read/write support
578 CONFIG_CMD_ELF * bootelf, bootvx
579 CONFIG_CMD_ENV saveenv
580 CONFIG_CMD_FDC * Floppy Disk Support
581 CONFIG_CMD_FAT * FAT partition support
582 CONFIG_CMD_FDOS * Dos diskette Support
583 CONFIG_CMD_FLASH flinfo, erase, protect
584 CONFIG_CMD_FPGA FPGA device initialization support
585 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
586 CONFIG_CMD_I2C * I2C serial bus support
587 CONFIG_CMD_IDE * IDE harddisk support
588 CONFIG_CMD_IMI iminfo
589 CONFIG_CMD_IMLS List all found images
590 CONFIG_CMD_IMMAP * IMMR dump support
591 CONFIG_CMD_IRQ * irqinfo
592 CONFIG_CMD_ITEST Integer/string test of 2 values
593 CONFIG_CMD_JFFS2 * JFFS2 Support
594 CONFIG_CMD_KGDB * kgdb
595 CONFIG_CMD_LOADB loadb
596 CONFIG_CMD_LOADS loads
597 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
598 loop, loopw, mtest
599 CONFIG_CMD_MISC Misc functions like sleep etc
600 CONFIG_CMD_MMC * MMC memory mapped support
601 CONFIG_CMD_MII * MII utility commands
602 CONFIG_CMD_NAND * NAND support
603 CONFIG_CMD_NET bootp, tftpboot, rarpboot
604 CONFIG_CMD_PCI * pciinfo
605 CONFIG_CMD_PCMCIA * PCMCIA support
606 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
607 host
608 CONFIG_CMD_PORTIO * Port I/O
609 CONFIG_CMD_REGINFO * Register dump
610 CONFIG_CMD_RUN run command in env variable
611 CONFIG_CMD_SAVES * save S record dump
612 CONFIG_CMD_SCSI * SCSI Support
613 CONFIG_CMD_SDRAM * print SDRAM configuration information
614 (requires CONFIG_CMD_I2C)
615 CONFIG_CMD_SETGETDCR Support for DCR Register access
616 (4xx only)
617 CONFIG_CMD_SPI * SPI serial bus support
618 CONFIG_CMD_USB * USB support
619 CONFIG_CMD_VFD * VFD support (TRAB)
620 CONFIG_CMD_CDP * Cisco Discover Protocol support
621 CONFIG_CMD_FSL * Microblaze FSL support
622
623
624 EXAMPLE: If you want all functions except of network
625 support you can write:
626
627 #include "config_cmd_all.h"
628 #undef CONFIG_CMD_NET
629
630 Other Commands:
631 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
632
633 Note: Don't enable the "icache" and "dcache" commands
634 (configuration option CONFIG_CMD_CACHE) unless you know
635 what you (and your U-Boot users) are doing. Data
636 cache cannot be enabled on systems like the 8xx or
637 8260 (where accesses to the IMMR region must be
638 uncached), and it cannot be disabled on all other
639 systems where we (mis-) use the data cache to hold an
640 initial stack and some data.
641
642
643 XXX - this list needs to get updated!
644
645 - Watchdog:
646 CONFIG_WATCHDOG
647 If this variable is defined, it enables watchdog
648 support. There must be support in the platform specific
649 code for a watchdog. For the 8xx and 8260 CPUs, the
650 SIU Watchdog feature is enabled in the SYPCR
651 register.
652
653 - U-Boot Version:
654 CONFIG_VERSION_VARIABLE
655 If this variable is defined, an environment variable
656 named "ver" is created by U-Boot showing the U-Boot
657 version as printed by the "version" command.
658 This variable is readonly.
659
660 - Real-Time Clock:
661
662 When CONFIG_CMD_DATE is selected, the type of the RTC
663 has to be selected, too. Define exactly one of the
664 following options:
665
666 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
667 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
668 CONFIG_RTC_MC13783 - use MC13783 RTC
669 CONFIG_RTC_MC146818 - use MC146818 RTC
670 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
671 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
672 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
673 CONFIG_RTC_DS164x - use Dallas DS164x RTC
674 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
675 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
676 CFG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
677
678 Note that if the RTC uses I2C, then the I2C interface
679 must also be configured. See I2C Support, below.
680
681 - Timestamp Support:
682
683 When CONFIG_TIMESTAMP is selected, the timestamp
684 (date and time) of an image is printed by image
685 commands like bootm or iminfo. This option is
686 automatically enabled when you select CONFIG_CMD_DATE .
687
688 - Partition Support:
689 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
690 and/or CONFIG_ISO_PARTITION
691
692 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
693 CONFIG_CMD_SCSI) you must configure support for at
694 least one partition type as well.
695
696 - IDE Reset method:
697 CONFIG_IDE_RESET_ROUTINE - this is defined in several
698 board configurations files but used nowhere!
699
700 CONFIG_IDE_RESET - is this is defined, IDE Reset will
701 be performed by calling the function
702 ide_set_reset(int reset)
703 which has to be defined in a board specific file
704
705 - ATAPI Support:
706 CONFIG_ATAPI
707
708 Set this to enable ATAPI support.
709
710 - LBA48 Support
711 CONFIG_LBA48
712
713 Set this to enable support for disks larger than 137GB
714 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
715 Whithout these , LBA48 support uses 32bit variables and will 'only'
716 support disks up to 2.1TB.
717
718 CFG_64BIT_LBA:
719 When enabled, makes the IDE subsystem use 64bit sector addresses.
720 Default is 32bit.
721
722 - SCSI Support:
723 At the moment only there is only support for the
724 SYM53C8XX SCSI controller; define
725 CONFIG_SCSI_SYM53C8XX to enable it.
726
727 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
728 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
729 CFG_SCSI_MAX_LUN] can be adjusted to define the
730 maximum numbers of LUNs, SCSI ID's and target
731 devices.
732 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
733
734 - NETWORK Support (PCI):
735 CONFIG_E1000
736 Support for Intel 8254x gigabit chips.
737
738 CONFIG_E1000_FALLBACK_MAC
739 default MAC for empty EEPROM after production.
740
741 CONFIG_EEPRO100
742 Support for Intel 82557/82559/82559ER chips.
743 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
744 write routine for first time initialisation.
745
746 CONFIG_TULIP
747 Support for Digital 2114x chips.
748 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
749 modem chip initialisation (KS8761/QS6611).
750
751 CONFIG_NATSEMI
752 Support for National dp83815 chips.
753
754 CONFIG_NS8382X
755 Support for National dp8382[01] gigabit chips.
756
757 - NETWORK Support (other):
758
759 CONFIG_DRIVER_LAN91C96
760 Support for SMSC's LAN91C96 chips.
761
762 CONFIG_LAN91C96_BASE
763 Define this to hold the physical address
764 of the LAN91C96's I/O space
765
766 CONFIG_LAN91C96_USE_32_BIT
767 Define this to enable 32 bit addressing
768
769 CONFIG_DRIVER_SMC91111
770 Support for SMSC's LAN91C111 chip
771
772 CONFIG_SMC91111_BASE
773 Define this to hold the physical address
774 of the device (I/O space)
775
776 CONFIG_SMC_USE_32_BIT
777 Define this if data bus is 32 bits
778
779 CONFIG_SMC_USE_IOFUNCS
780 Define this to use i/o functions instead of macros
781 (some hardware wont work with macros)
782
783 CONFIG_DRIVER_SMC911X
784 Support for SMSC's LAN911x and LAN921x chips
785
786 CONFIG_DRIVER_SMC911X_BASE
787 Define this to hold the physical address
788 of the device (I/O space)
789
790 CONFIG_DRIVER_SMC911X_32_BIT
791 Define this if data bus is 32 bits
792
793 CONFIG_DRIVER_SMC911X_16_BIT
794 Define this if data bus is 16 bits. If your processor
795 automatically converts one 32 bit word to two 16 bit
796 words you may also try CONFIG_DRIVER_SMC911X_32_BIT.
797
798 - USB Support:
799 At the moment only the UHCI host controller is
800 supported (PIP405, MIP405, MPC5200); define
801 CONFIG_USB_UHCI to enable it.
802 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
803 and define CONFIG_USB_STORAGE to enable the USB
804 storage devices.
805 Note:
806 Supported are USB Keyboards and USB Floppy drives
807 (TEAC FD-05PUB).
808 MPC5200 USB requires additional defines:
809 CONFIG_USB_CLOCK
810 for 528 MHz Clock: 0x0001bbbb
811 CONFIG_USB_CONFIG
812 for differential drivers: 0x00001000
813 for single ended drivers: 0x00005000
814 CFG_USB_EVENT_POLL
815 May be defined to allow interrupt polling
816 instead of using asynchronous interrupts
817
818 - USB Device:
819 Define the below if you wish to use the USB console.
820 Once firmware is rebuilt from a serial console issue the
821 command "setenv stdin usbtty; setenv stdout usbtty" and
822 attach your USB cable. The Unix command "dmesg" should print
823 it has found a new device. The environment variable usbtty
824 can be set to gserial or cdc_acm to enable your device to
825 appear to a USB host as a Linux gserial device or a
826 Common Device Class Abstract Control Model serial device.
827 If you select usbtty = gserial you should be able to enumerate
828 a Linux host by
829 # modprobe usbserial vendor=0xVendorID product=0xProductID
830 else if using cdc_acm, simply setting the environment
831 variable usbtty to be cdc_acm should suffice. The following
832 might be defined in YourBoardName.h
833
834 CONFIG_USB_DEVICE
835 Define this to build a UDC device
836
837 CONFIG_USB_TTY
838 Define this to have a tty type of device available to
839 talk to the UDC device
840
841 CFG_CONSOLE_IS_IN_ENV
842 Define this if you want stdin, stdout &/or stderr to
843 be set to usbtty.
844
845 mpc8xx:
846 CFG_USB_EXTC_CLK 0xBLAH
847 Derive USB clock from external clock "blah"
848 - CFG_USB_EXTC_CLK 0x02
849
850 CFG_USB_BRG_CLK 0xBLAH
851 Derive USB clock from brgclk
852 - CFG_USB_BRG_CLK 0x04
853
854 If you have a USB-IF assigned VendorID then you may wish to
855 define your own vendor specific values either in BoardName.h
856 or directly in usbd_vendor_info.h. If you don't define
857 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
858 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
859 should pretend to be a Linux device to it's target host.
860
861 CONFIG_USBD_MANUFACTURER
862 Define this string as the name of your company for
863 - CONFIG_USBD_MANUFACTURER "my company"
864
865 CONFIG_USBD_PRODUCT_NAME
866 Define this string as the name of your product
867 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
868
869 CONFIG_USBD_VENDORID
870 Define this as your assigned Vendor ID from the USB
871 Implementors Forum. This *must* be a genuine Vendor ID
872 to avoid polluting the USB namespace.
873 - CONFIG_USBD_VENDORID 0xFFFF
874
875 CONFIG_USBD_PRODUCTID
876 Define this as the unique Product ID
877 for your device
878 - CONFIG_USBD_PRODUCTID 0xFFFF
879
880
881 - MMC Support:
882 The MMC controller on the Intel PXA is supported. To
883 enable this define CONFIG_MMC. The MMC can be
884 accessed from the boot prompt by mapping the device
885 to physical memory similar to flash. Command line is
886 enabled with CONFIG_CMD_MMC. The MMC driver also works with
887 the FAT fs. This is enabled with CONFIG_CMD_FAT.
888
889 - Journaling Flash filesystem support:
890 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
891 CONFIG_JFFS2_NAND_DEV
892 Define these for a default partition on a NAND device
893
894 CFG_JFFS2_FIRST_SECTOR,
895 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
896 Define these for a default partition on a NOR device
897
898 CFG_JFFS_CUSTOM_PART
899 Define this to create an own partition. You have to provide a
900 function struct part_info* jffs2_part_info(int part_num)
901
902 If you define only one JFFS2 partition you may also want to
903 #define CFG_JFFS_SINGLE_PART 1
904 to disable the command chpart. This is the default when you
905 have not defined a custom partition
906
907 - Keyboard Support:
908 CONFIG_ISA_KEYBOARD
909
910 Define this to enable standard (PC-Style) keyboard
911 support
912
913 CONFIG_I8042_KBD
914 Standard PC keyboard driver with US (is default) and
915 GERMAN key layout (switch via environment 'keymap=de') support.
916 Export function i8042_kbd_init, i8042_tstc and i8042_getc
917 for cfb_console. Supports cursor blinking.
918
919 - Video support:
920 CONFIG_VIDEO
921
922 Define this to enable video support (for output to
923 video).
924
925 CONFIG_VIDEO_CT69000
926
927 Enable Chips & Technologies 69000 Video chip
928
929 CONFIG_VIDEO_SMI_LYNXEM
930 Enable Silicon Motion SMI 712/710/810 Video chip. The
931 video output is selected via environment 'videoout'
932 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
933 assumed.
934
935 For the CT69000 and SMI_LYNXEM drivers, videomode is
936 selected via environment 'videomode'. Two different ways
937 are possible:
938 - "videomode=num" 'num' is a standard LiLo mode numbers.
939 Following standard modes are supported (* is default):
940
941 Colors 640x480 800x600 1024x768 1152x864 1280x1024
942 -------------+---------------------------------------------
943 8 bits | 0x301* 0x303 0x305 0x161 0x307
944 15 bits | 0x310 0x313 0x316 0x162 0x319
945 16 bits | 0x311 0x314 0x317 0x163 0x31A
946 24 bits | 0x312 0x315 0x318 ? 0x31B
947 -------------+---------------------------------------------
948 (i.e. setenv videomode 317; saveenv; reset;)
949
950 - "videomode=bootargs" all the video parameters are parsed
951 from the bootargs. (See drivers/video/videomodes.c)
952
953
954 CONFIG_VIDEO_SED13806
955 Enable Epson SED13806 driver. This driver supports 8bpp
956 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
957 or CONFIG_VIDEO_SED13806_16BPP
958
959 - Keyboard Support:
960 CONFIG_KEYBOARD
961
962 Define this to enable a custom keyboard support.
963 This simply calls drv_keyboard_init() which must be
964 defined in your board-specific files.
965 The only board using this so far is RBC823.
966
967 - LCD Support: CONFIG_LCD
968
969 Define this to enable LCD support (for output to LCD
970 display); also select one of the supported displays
971 by defining one of these:
972
973 CONFIG_ATMEL_LCD:
974
975 HITACHI TX09D70VM1CCA, 3.5", 240x320.
976
977 CONFIG_NEC_NL6448AC33:
978
979 NEC NL6448AC33-18. Active, color, single scan.
980
981 CONFIG_NEC_NL6448BC20
982
983 NEC NL6448BC20-08. 6.5", 640x480.
984 Active, color, single scan.
985
986 CONFIG_NEC_NL6448BC33_54
987
988 NEC NL6448BC33-54. 10.4", 640x480.
989 Active, color, single scan.
990
991 CONFIG_SHARP_16x9
992
993 Sharp 320x240. Active, color, single scan.
994 It isn't 16x9, and I am not sure what it is.
995
996 CONFIG_SHARP_LQ64D341
997
998 Sharp LQ64D341 display, 640x480.
999 Active, color, single scan.
1000
1001 CONFIG_HLD1045
1002
1003 HLD1045 display, 640x480.
1004 Active, color, single scan.
1005
1006 CONFIG_OPTREX_BW
1007
1008 Optrex CBL50840-2 NF-FW 99 22 M5
1009 or
1010 Hitachi LMG6912RPFC-00T
1011 or
1012 Hitachi SP14Q002
1013
1014 320x240. Black & white.
1015
1016 Normally display is black on white background; define
1017 CFG_WHITE_ON_BLACK to get it inverted.
1018
1019 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1020
1021 If this option is set, the environment is checked for
1022 a variable "splashimage". If found, the usual display
1023 of logo, copyright and system information on the LCD
1024 is suppressed and the BMP image at the address
1025 specified in "splashimage" is loaded instead. The
1026 console is redirected to the "nulldev", too. This
1027 allows for a "silent" boot where a splash screen is
1028 loaded very quickly after power-on.
1029
1030 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1031
1032 If this option is set, additionally to standard BMP
1033 images, gzipped BMP images can be displayed via the
1034 splashscreen support or the bmp command.
1035
1036 - Compression support:
1037 CONFIG_BZIP2
1038
1039 If this option is set, support for bzip2 compressed
1040 images is included. If not, only uncompressed and gzip
1041 compressed images are supported.
1042
1043 NOTE: the bzip2 algorithm requires a lot of RAM, so
1044 the malloc area (as defined by CFG_MALLOC_LEN) should
1045 be at least 4MB.
1046
1047 - MII/PHY support:
1048 CONFIG_PHY_ADDR
1049
1050 The address of PHY on MII bus.
1051
1052 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1053
1054 The clock frequency of the MII bus
1055
1056 CONFIG_PHY_GIGE
1057
1058 If this option is set, support for speed/duplex
1059 detection of gigabit PHY is included.
1060
1061 CONFIG_PHY_RESET_DELAY
1062
1063 Some PHY like Intel LXT971A need extra delay after
1064 reset before any MII register access is possible.
1065 For such PHY, set this option to the usec delay
1066 required. (minimum 300usec for LXT971A)
1067
1068 CONFIG_PHY_CMD_DELAY (ppc4xx)
1069
1070 Some PHY like Intel LXT971A need extra delay after
1071 command issued before MII status register can be read
1072
1073 - Ethernet address:
1074 CONFIG_ETHADDR
1075 CONFIG_ETH2ADDR
1076 CONFIG_ETH3ADDR
1077
1078 Define a default value for Ethernet address to use
1079 for the respective Ethernet interface, in case this
1080 is not determined automatically.
1081
1082 - IP address:
1083 CONFIG_IPADDR
1084
1085 Define a default value for the IP address to use for
1086 the default Ethernet interface, in case this is not
1087 determined through e.g. bootp.
1088
1089 - Server IP address:
1090 CONFIG_SERVERIP
1091
1092 Defines a default value for the IP address of a TFTP
1093 server to contact when using the "tftboot" command.
1094
1095 - Multicast TFTP Mode:
1096 CONFIG_MCAST_TFTP
1097
1098 Defines whether you want to support multicast TFTP as per
1099 rfc-2090; for example to work with atftp. Lets lots of targets
1100 tftp down the same boot image concurrently. Note: the Ethernet
1101 driver in use must provide a function: mcast() to join/leave a
1102 multicast group.
1103
1104 CONFIG_BOOTP_RANDOM_DELAY
1105 - BOOTP Recovery Mode:
1106 CONFIG_BOOTP_RANDOM_DELAY
1107
1108 If you have many targets in a network that try to
1109 boot using BOOTP, you may want to avoid that all
1110 systems send out BOOTP requests at precisely the same
1111 moment (which would happen for instance at recovery
1112 from a power failure, when all systems will try to
1113 boot, thus flooding the BOOTP server. Defining
1114 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1115 inserted before sending out BOOTP requests. The
1116 following delays are inserted then:
1117
1118 1st BOOTP request: delay 0 ... 1 sec
1119 2nd BOOTP request: delay 0 ... 2 sec
1120 3rd BOOTP request: delay 0 ... 4 sec
1121 4th and following
1122 BOOTP requests: delay 0 ... 8 sec
1123
1124 - DHCP Advanced Options:
1125 You can fine tune the DHCP functionality by defining
1126 CONFIG_BOOTP_* symbols:
1127
1128 CONFIG_BOOTP_SUBNETMASK
1129 CONFIG_BOOTP_GATEWAY
1130 CONFIG_BOOTP_HOSTNAME
1131 CONFIG_BOOTP_NISDOMAIN
1132 CONFIG_BOOTP_BOOTPATH
1133 CONFIG_BOOTP_BOOTFILESIZE
1134 CONFIG_BOOTP_DNS
1135 CONFIG_BOOTP_DNS2
1136 CONFIG_BOOTP_SEND_HOSTNAME
1137 CONFIG_BOOTP_NTPSERVER
1138 CONFIG_BOOTP_TIMEOFFSET
1139 CONFIG_BOOTP_VENDOREX
1140
1141 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1142 environment variable, not the BOOTP server.
1143
1144 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1145 serverip from a DHCP server, it is possible that more
1146 than one DNS serverip is offered to the client.
1147 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1148 serverip will be stored in the additional environment
1149 variable "dnsip2". The first DNS serverip is always
1150 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1151 is defined.
1152
1153 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1154 to do a dynamic update of a DNS server. To do this, they
1155 need the hostname of the DHCP requester.
1156 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1157 of the "hostname" environment variable is passed as
1158 option 12 to the DHCP server.
1159
1160 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1161
1162 A 32bit value in microseconds for a delay between
1163 receiving a "DHCP Offer" and sending the "DHCP Request".
1164 This fixes a problem with certain DHCP servers that don't
1165 respond 100% of the time to a "DHCP request". E.g. On an
1166 AT91RM9200 processor running at 180MHz, this delay needed
1167 to be *at least* 15,000 usec before a Windows Server 2003
1168 DHCP server would reply 100% of the time. I recommend at
1169 least 50,000 usec to be safe. The alternative is to hope
1170 that one of the retries will be successful but note that
1171 the DHCP timeout and retry process takes a longer than
1172 this delay.
1173
1174 - CDP Options:
1175 CONFIG_CDP_DEVICE_ID
1176
1177 The device id used in CDP trigger frames.
1178
1179 CONFIG_CDP_DEVICE_ID_PREFIX
1180
1181 A two character string which is prefixed to the MAC address
1182 of the device.
1183
1184 CONFIG_CDP_PORT_ID
1185
1186 A printf format string which contains the ascii name of
1187 the port. Normally is set to "eth%d" which sets
1188 eth0 for the first Ethernet, eth1 for the second etc.
1189
1190 CONFIG_CDP_CAPABILITIES
1191
1192 A 32bit integer which indicates the device capabilities;
1193 0x00000010 for a normal host which does not forwards.
1194
1195 CONFIG_CDP_VERSION
1196
1197 An ascii string containing the version of the software.
1198
1199 CONFIG_CDP_PLATFORM
1200
1201 An ascii string containing the name of the platform.
1202
1203 CONFIG_CDP_TRIGGER
1204
1205 A 32bit integer sent on the trigger.
1206
1207 CONFIG_CDP_POWER_CONSUMPTION
1208
1209 A 16bit integer containing the power consumption of the
1210 device in .1 of milliwatts.
1211
1212 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1213
1214 A byte containing the id of the VLAN.
1215
1216 - Status LED: CONFIG_STATUS_LED
1217
1218 Several configurations allow to display the current
1219 status using a LED. For instance, the LED will blink
1220 fast while running U-Boot code, stop blinking as
1221 soon as a reply to a BOOTP request was received, and
1222 start blinking slow once the Linux kernel is running
1223 (supported by a status LED driver in the Linux
1224 kernel). Defining CONFIG_STATUS_LED enables this
1225 feature in U-Boot.
1226
1227 - CAN Support: CONFIG_CAN_DRIVER
1228
1229 Defining CONFIG_CAN_DRIVER enables CAN driver support
1230 on those systems that support this (optional)
1231 feature, like the TQM8xxL modules.
1232
1233 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1234
1235 These enable I2C serial bus commands. Defining either of
1236 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1237 include the appropriate I2C driver for the selected CPU.
1238
1239 This will allow you to use i2c commands at the u-boot
1240 command line (as long as you set CONFIG_CMD_I2C in
1241 CONFIG_COMMANDS) and communicate with i2c based realtime
1242 clock chips. See common/cmd_i2c.c for a description of the
1243 command line interface.
1244
1245 CONFIG_I2C_CMD_TREE is a recommended option that places
1246 all I2C commands under a single 'i2c' root command. The
1247 older 'imm', 'imd', 'iprobe' etc. commands are considered
1248 deprecated and may disappear in the future.
1249
1250 CONFIG_HARD_I2C selects a hardware I2C controller.
1251
1252 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1253 bit-banging) driver instead of CPM or similar hardware
1254 support for I2C.
1255
1256 There are several other quantities that must also be
1257 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1258
1259 In both cases you will need to define CFG_I2C_SPEED
1260 to be the frequency (in Hz) at which you wish your i2c bus
1261 to run and CFG_I2C_SLAVE to be the address of this node (ie
1262 the CPU's i2c node address).
1263
1264 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1265 sets the CPU up as a master node and so its address should
1266 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1267 p.16-473). So, set CFG_I2C_SLAVE to 0.
1268
1269 That's all that's required for CONFIG_HARD_I2C.
1270
1271 If you use the software i2c interface (CONFIG_SOFT_I2C)
1272 then the following macros need to be defined (examples are
1273 from include/configs/lwmon.h):
1274
1275 I2C_INIT
1276
1277 (Optional). Any commands necessary to enable the I2C
1278 controller or configure ports.
1279
1280 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1281
1282 I2C_PORT
1283
1284 (Only for MPC8260 CPU). The I/O port to use (the code
1285 assumes both bits are on the same port). Valid values
1286 are 0..3 for ports A..D.
1287
1288 I2C_ACTIVE
1289
1290 The code necessary to make the I2C data line active
1291 (driven). If the data line is open collector, this
1292 define can be null.
1293
1294 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1295
1296 I2C_TRISTATE
1297
1298 The code necessary to make the I2C data line tri-stated
1299 (inactive). If the data line is open collector, this
1300 define can be null.
1301
1302 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1303
1304 I2C_READ
1305
1306 Code that returns TRUE if the I2C data line is high,
1307 FALSE if it is low.
1308
1309 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1310
1311 I2C_SDA(bit)
1312
1313 If <bit> is TRUE, sets the I2C data line high. If it
1314 is FALSE, it clears it (low).
1315
1316 eg: #define I2C_SDA(bit) \
1317 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1318 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1319
1320 I2C_SCL(bit)
1321
1322 If <bit> is TRUE, sets the I2C clock line high. If it
1323 is FALSE, it clears it (low).
1324
1325 eg: #define I2C_SCL(bit) \
1326 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1327 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1328
1329 I2C_DELAY
1330
1331 This delay is invoked four times per clock cycle so this
1332 controls the rate of data transfer. The data rate thus
1333 is 1 / (I2C_DELAY * 4). Often defined to be something
1334 like:
1335
1336 #define I2C_DELAY udelay(2)
1337
1338 CFG_I2C_INIT_BOARD
1339
1340 When a board is reset during an i2c bus transfer
1341 chips might think that the current transfer is still
1342 in progress. On some boards it is possible to access
1343 the i2c SCLK line directly, either by using the
1344 processor pin as a GPIO or by having a second pin
1345 connected to the bus. If this option is defined a
1346 custom i2c_init_board() routine in boards/xxx/board.c
1347 is run early in the boot sequence.
1348
1349 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1350
1351 This option enables configuration of bi_iic_fast[] flags
1352 in u-boot bd_info structure based on u-boot environment
1353 variable "i2cfast". (see also i2cfast)
1354
1355 CONFIG_I2C_MULTI_BUS
1356
1357 This option allows the use of multiple I2C buses, each of which
1358 must have a controller. At any point in time, only one bus is
1359 active. To switch to a different bus, use the 'i2c dev' command.
1360 Note that bus numbering is zero-based.
1361
1362 CFG_I2C_NOPROBES
1363
1364 This option specifies a list of I2C devices that will be skipped
1365 when the 'i2c probe' command is issued (or 'iprobe' using the legacy
1366 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device
1367 pairs. Otherwise, specify a 1D array of device addresses
1368
1369 e.g.
1370 #undef CONFIG_I2C_MULTI_BUS
1371 #define CFG_I2C_NOPROBES {0x50,0x68}
1372
1373 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1374
1375 #define CONFIG_I2C_MULTI_BUS
1376 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1377
1378 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1379
1380 CFG_SPD_BUS_NUM
1381
1382 If defined, then this indicates the I2C bus number for DDR SPD.
1383 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1384
1385 CFG_RTC_BUS_NUM
1386
1387 If defined, then this indicates the I2C bus number for the RTC.
1388 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1389
1390 CFG_DTT_BUS_NUM
1391
1392 If defined, then this indicates the I2C bus number for the DTT.
1393 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1394
1395 CONFIG_FSL_I2C
1396
1397 Define this option if you want to use Freescale's I2C driver in
1398 drivers/i2c/fsl_i2c.c.
1399
1400
1401 - SPI Support: CONFIG_SPI
1402
1403 Enables SPI driver (so far only tested with
1404 SPI EEPROM, also an instance works with Crystal A/D and
1405 D/As on the SACSng board)
1406
1407 CONFIG_SPI_X
1408
1409 Enables extended (16-bit) SPI EEPROM addressing.
1410 (symmetrical to CONFIG_I2C_X)
1411
1412 CONFIG_SOFT_SPI
1413
1414 Enables a software (bit-bang) SPI driver rather than
1415 using hardware support. This is a general purpose
1416 driver that only requires three general I/O port pins
1417 (two outputs, one input) to function. If this is
1418 defined, the board configuration must define several
1419 SPI configuration items (port pins to use, etc). For
1420 an example, see include/configs/sacsng.h.
1421
1422 CONFIG_HARD_SPI
1423
1424 Enables a hardware SPI driver for general-purpose reads
1425 and writes. As with CONFIG_SOFT_SPI, the board configuration
1426 must define a list of chip-select function pointers.
1427 Currently supported on some MPC8xxx processors. For an
1428 example, see include/configs/mpc8349emds.h.
1429
1430 CONFIG_MXC_SPI
1431
1432 Enables the driver for the SPI controllers on i.MX and MXC
1433 SoCs. Currently only i.MX31 is supported.
1434
1435 - FPGA Support: CONFIG_FPGA
1436
1437 Enables FPGA subsystem.
1438
1439 CONFIG_FPGA_<vendor>
1440
1441 Enables support for specific chip vendors.
1442 (ALTERA, XILINX)
1443
1444 CONFIG_FPGA_<family>
1445
1446 Enables support for FPGA family.
1447 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1448
1449 CONFIG_FPGA_COUNT
1450
1451 Specify the number of FPGA devices to support.
1452
1453 CFG_FPGA_PROG_FEEDBACK
1454
1455 Enable printing of hash marks during FPGA configuration.
1456
1457 CFG_FPGA_CHECK_BUSY
1458
1459 Enable checks on FPGA configuration interface busy
1460 status by the configuration function. This option
1461 will require a board or device specific function to
1462 be written.
1463
1464 CONFIG_FPGA_DELAY
1465
1466 If defined, a function that provides delays in the FPGA
1467 configuration driver.
1468
1469 CFG_FPGA_CHECK_CTRLC
1470 Allow Control-C to interrupt FPGA configuration
1471
1472 CFG_FPGA_CHECK_ERROR
1473
1474 Check for configuration errors during FPGA bitfile
1475 loading. For example, abort during Virtex II
1476 configuration if the INIT_B line goes low (which
1477 indicated a CRC error).
1478
1479 CFG_FPGA_WAIT_INIT
1480
1481 Maximum time to wait for the INIT_B line to deassert
1482 after PROB_B has been deasserted during a Virtex II
1483 FPGA configuration sequence. The default time is 500
1484 ms.
1485
1486 CFG_FPGA_WAIT_BUSY
1487
1488 Maximum time to wait for BUSY to deassert during
1489 Virtex II FPGA configuration. The default is 5 ms.
1490
1491 CFG_FPGA_WAIT_CONFIG
1492
1493 Time to wait after FPGA configuration. The default is
1494 200 ms.
1495
1496 - Configuration Management:
1497 CONFIG_IDENT_STRING
1498
1499 If defined, this string will be added to the U-Boot
1500 version information (U_BOOT_VERSION)
1501
1502 - Vendor Parameter Protection:
1503
1504 U-Boot considers the values of the environment
1505 variables "serial#" (Board Serial Number) and
1506 "ethaddr" (Ethernet Address) to be parameters that
1507 are set once by the board vendor / manufacturer, and
1508 protects these variables from casual modification by
1509 the user. Once set, these variables are read-only,
1510 and write or delete attempts are rejected. You can
1511 change this behaviour:
1512
1513 If CONFIG_ENV_OVERWRITE is #defined in your config
1514 file, the write protection for vendor parameters is
1515 completely disabled. Anybody can change or delete
1516 these parameters.
1517
1518 Alternatively, if you #define _both_ CONFIG_ETHADDR
1519 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1520 Ethernet address is installed in the environment,
1521 which can be changed exactly ONCE by the user. [The
1522 serial# is unaffected by this, i. e. it remains
1523 read-only.]
1524
1525 - Protected RAM:
1526 CONFIG_PRAM
1527
1528 Define this variable to enable the reservation of
1529 "protected RAM", i. e. RAM which is not overwritten
1530 by U-Boot. Define CONFIG_PRAM to hold the number of
1531 kB you want to reserve for pRAM. You can overwrite
1532 this default value by defining an environment
1533 variable "pram" to the number of kB you want to
1534 reserve. Note that the board info structure will
1535 still show the full amount of RAM. If pRAM is
1536 reserved, a new environment variable "mem" will
1537 automatically be defined to hold the amount of
1538 remaining RAM in a form that can be passed as boot
1539 argument to Linux, for instance like that:
1540
1541 setenv bootargs ... mem=\${mem}
1542 saveenv
1543
1544 This way you can tell Linux not to use this memory,
1545 either, which results in a memory region that will
1546 not be affected by reboots.
1547
1548 *WARNING* If your board configuration uses automatic
1549 detection of the RAM size, you must make sure that
1550 this memory test is non-destructive. So far, the
1551 following board configurations are known to be
1552 "pRAM-clean":
1553
1554 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1555 HERMES, IP860, RPXlite, LWMON, LANTEC,
1556 PCU_E, FLAGADM, TQM8260
1557
1558 - Error Recovery:
1559 CONFIG_PANIC_HANG
1560
1561 Define this variable to stop the system in case of a
1562 fatal error, so that you have to reset it manually.
1563 This is probably NOT a good idea for an embedded
1564 system where you want the system to reboot
1565 automatically as fast as possible, but it may be
1566 useful during development since you can try to debug
1567 the conditions that lead to the situation.
1568
1569 CONFIG_NET_RETRY_COUNT
1570
1571 This variable defines the number of retries for
1572 network operations like ARP, RARP, TFTP, or BOOTP
1573 before giving up the operation. If not defined, a
1574 default value of 5 is used.
1575
1576 CONFIG_ARP_TIMEOUT
1577
1578 Timeout waiting for an ARP reply in milliseconds.
1579
1580 - Command Interpreter:
1581 CONFIG_AUTO_COMPLETE
1582
1583 Enable auto completion of commands using TAB.
1584
1585 Note that this feature has NOT been implemented yet
1586 for the "hush" shell.
1587
1588
1589 CFG_HUSH_PARSER
1590
1591 Define this variable to enable the "hush" shell (from
1592 Busybox) as command line interpreter, thus enabling
1593 powerful command line syntax like
1594 if...then...else...fi conditionals or `&&' and '||'
1595 constructs ("shell scripts").
1596
1597 If undefined, you get the old, much simpler behaviour
1598 with a somewhat smaller memory footprint.
1599
1600
1601 CFG_PROMPT_HUSH_PS2
1602
1603 This defines the secondary prompt string, which is
1604 printed when the command interpreter needs more input
1605 to complete a command. Usually "> ".
1606
1607 Note:
1608
1609 In the current implementation, the local variables
1610 space and global environment variables space are
1611 separated. Local variables are those you define by
1612 simply typing `name=value'. To access a local
1613 variable later on, you have write `$name' or
1614 `${name}'; to execute the contents of a variable
1615 directly type `$name' at the command prompt.
1616
1617 Global environment variables are those you use
1618 setenv/printenv to work with. To run a command stored
1619 in such a variable, you need to use the run command,
1620 and you must not use the '$' sign to access them.
1621
1622 To store commands and special characters in a
1623 variable, please use double quotation marks
1624 surrounding the whole text of the variable, instead
1625 of the backslashes before semicolons and special
1626 symbols.
1627
1628 - Commandline Editing and History:
1629 CONFIG_CMDLINE_EDITING
1630
1631 Enable editing and History functions for interactive
1632 commandline input operations
1633
1634 - Default Environment:
1635 CONFIG_EXTRA_ENV_SETTINGS
1636
1637 Define this to contain any number of null terminated
1638 strings (variable = value pairs) that will be part of
1639 the default environment compiled into the boot image.
1640
1641 For example, place something like this in your
1642 board's config file:
1643
1644 #define CONFIG_EXTRA_ENV_SETTINGS \
1645 "myvar1=value1\0" \
1646 "myvar2=value2\0"
1647
1648 Warning: This method is based on knowledge about the
1649 internal format how the environment is stored by the
1650 U-Boot code. This is NOT an official, exported
1651 interface! Although it is unlikely that this format
1652 will change soon, there is no guarantee either.
1653 You better know what you are doing here.
1654
1655 Note: overly (ab)use of the default environment is
1656 discouraged. Make sure to check other ways to preset
1657 the environment like the autoscript function or the
1658 boot command first.
1659
1660 - DataFlash Support:
1661 CONFIG_HAS_DATAFLASH
1662
1663 Defining this option enables DataFlash features and
1664 allows to read/write in Dataflash via the standard
1665 commands cp, md...
1666
1667 - SystemACE Support:
1668 CONFIG_SYSTEMACE
1669
1670 Adding this option adds support for Xilinx SystemACE
1671 chips attached via some sort of local bus. The address
1672 of the chip must also be defined in the
1673 CFG_SYSTEMACE_BASE macro. For example:
1674
1675 #define CONFIG_SYSTEMACE
1676 #define CFG_SYSTEMACE_BASE 0xf0000000
1677
1678 When SystemACE support is added, the "ace" device type
1679 becomes available to the fat commands, i.e. fatls.
1680
1681 - TFTP Fixed UDP Port:
1682 CONFIG_TFTP_PORT
1683
1684 If this is defined, the environment variable tftpsrcp
1685 is used to supply the TFTP UDP source port value.
1686 If tftpsrcp isn't defined, the normal pseudo-random port
1687 number generator is used.
1688
1689 Also, the environment variable tftpdstp is used to supply
1690 the TFTP UDP destination port value. If tftpdstp isn't
1691 defined, the normal port 69 is used.
1692
1693 The purpose for tftpsrcp is to allow a TFTP server to
1694 blindly start the TFTP transfer using the pre-configured
1695 target IP address and UDP port. This has the effect of
1696 "punching through" the (Windows XP) firewall, allowing
1697 the remainder of the TFTP transfer to proceed normally.
1698 A better solution is to properly configure the firewall,
1699 but sometimes that is not allowed.
1700
1701 - Show boot progress:
1702 CONFIG_SHOW_BOOT_PROGRESS
1703
1704 Defining this option allows to add some board-
1705 specific code (calling a user-provided function
1706 "show_boot_progress(int)") that enables you to show
1707 the system's boot progress on some display (for
1708 example, some LED's) on your board. At the moment,
1709 the following checkpoints are implemented:
1710
1711 Legacy uImage format:
1712
1713 Arg Where When
1714 1 common/cmd_bootm.c before attempting to boot an image
1715 -1 common/cmd_bootm.c Image header has bad magic number
1716 2 common/cmd_bootm.c Image header has correct magic number
1717 -2 common/cmd_bootm.c Image header has bad checksum
1718 3 common/cmd_bootm.c Image header has correct checksum
1719 -3 common/cmd_bootm.c Image data has bad checksum
1720 4 common/cmd_bootm.c Image data has correct checksum
1721 -4 common/cmd_bootm.c Image is for unsupported architecture
1722 5 common/cmd_bootm.c Architecture check OK
1723 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
1724 6 common/cmd_bootm.c Image Type check OK
1725 -6 common/cmd_bootm.c gunzip uncompression error
1726 -7 common/cmd_bootm.c Unimplemented compression type
1727 7 common/cmd_bootm.c Uncompression OK
1728 8 common/cmd_bootm.c No uncompress/copy overwrite error
1729 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1730
1731 9 common/image.c Start initial ramdisk verification
1732 -10 common/image.c Ramdisk header has bad magic number
1733 -11 common/image.c Ramdisk header has bad checksum
1734 10 common/image.c Ramdisk header is OK
1735 -12 common/image.c Ramdisk data has bad checksum
1736 11 common/image.c Ramdisk data has correct checksum
1737 12 common/image.c Ramdisk verification complete, start loading
1738 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
1739 13 common/image.c Start multifile image verification
1740 14 common/image.c No initial ramdisk, no multifile, continue.
1741
1742 15 lib_<arch>/bootm.c All preparation done, transferring control to OS
1743
1744 -30 lib_ppc/board.c Fatal error, hang the system
1745 -31 post/post.c POST test failed, detected by post_output_backlog()
1746 -32 post/post.c POST test failed, detected by post_run_single()
1747
1748 34 common/cmd_doc.c before loading a Image from a DOC device
1749 -35 common/cmd_doc.c Bad usage of "doc" command
1750 35 common/cmd_doc.c correct usage of "doc" command
1751 -36 common/cmd_doc.c No boot device
1752 36 common/cmd_doc.c correct boot device
1753 -37 common/cmd_doc.c Unknown Chip ID on boot device
1754 37 common/cmd_doc.c correct chip ID found, device available
1755 -38 common/cmd_doc.c Read Error on boot device
1756 38 common/cmd_doc.c reading Image header from DOC device OK
1757 -39 common/cmd_doc.c Image header has bad magic number
1758 39 common/cmd_doc.c Image header has correct magic number
1759 -40 common/cmd_doc.c Error reading Image from DOC device
1760 40 common/cmd_doc.c Image header has correct magic number
1761 41 common/cmd_ide.c before loading a Image from a IDE device
1762 -42 common/cmd_ide.c Bad usage of "ide" command
1763 42 common/cmd_ide.c correct usage of "ide" command
1764 -43 common/cmd_ide.c No boot device
1765 43 common/cmd_ide.c boot device found
1766 -44 common/cmd_ide.c Device not available
1767 44 common/cmd_ide.c Device available
1768 -45 common/cmd_ide.c wrong partition selected
1769 45 common/cmd_ide.c partition selected
1770 -46 common/cmd_ide.c Unknown partition table
1771 46 common/cmd_ide.c valid partition table found
1772 -47 common/cmd_ide.c Invalid partition type
1773 47 common/cmd_ide.c correct partition type
1774 -48 common/cmd_ide.c Error reading Image Header on boot device
1775 48 common/cmd_ide.c reading Image Header from IDE device OK
1776 -49 common/cmd_ide.c Image header has bad magic number
1777 49 common/cmd_ide.c Image header has correct magic number
1778 -50 common/cmd_ide.c Image header has bad checksum
1779 50 common/cmd_ide.c Image header has correct checksum
1780 -51 common/cmd_ide.c Error reading Image from IDE device
1781 51 common/cmd_ide.c reading Image from IDE device OK
1782 52 common/cmd_nand.c before loading a Image from a NAND device
1783 -53 common/cmd_nand.c Bad usage of "nand" command
1784 53 common/cmd_nand.c correct usage of "nand" command
1785 -54 common/cmd_nand.c No boot device
1786 54 common/cmd_nand.c boot device found
1787 -55 common/cmd_nand.c Unknown Chip ID on boot device
1788 55 common/cmd_nand.c correct chip ID found, device available
1789 -56 common/cmd_nand.c Error reading Image Header on boot device
1790 56 common/cmd_nand.c reading Image Header from NAND device OK
1791 -57 common/cmd_nand.c Image header has bad magic number
1792 57 common/cmd_nand.c Image header has correct magic number
1793 -58 common/cmd_nand.c Error reading Image from NAND device
1794 58 common/cmd_nand.c reading Image from NAND device OK
1795
1796 -60 common/env_common.c Environment has a bad CRC, using default
1797
1798 64 net/eth.c starting with Ethernet configuration.
1799 -64 net/eth.c no Ethernet found.
1800 65 net/eth.c Ethernet found.
1801
1802 -80 common/cmd_net.c usage wrong
1803 80 common/cmd_net.c before calling NetLoop()
1804 -81 common/cmd_net.c some error in NetLoop() occurred
1805 81 common/cmd_net.c NetLoop() back without error
1806 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
1807 82 common/cmd_net.c trying automatic boot
1808 83 common/cmd_net.c running autoscript
1809 -83 common/cmd_net.c some error in automatic boot or autoscript
1810 84 common/cmd_net.c end without errors
1811
1812 FIT uImage format:
1813
1814 Arg Where When
1815 100 common/cmd_bootm.c Kernel FIT Image has correct format
1816 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
1817 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
1818 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
1819 102 common/cmd_bootm.c Kernel unit name specified
1820 -103 common/cmd_bootm.c Can't get kernel subimage node offset
1821 103 common/cmd_bootm.c Found configuration node
1822 104 common/cmd_bootm.c Got kernel subimage node offset
1823 -104 common/cmd_bootm.c Kernel subimage hash verification failed
1824 105 common/cmd_bootm.c Kernel subimage hash verification OK
1825 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
1826 106 common/cmd_bootm.c Architecture check OK
1827 -106 common/cmd_bootm.c Kernel subimage has wrong type
1828 107 common/cmd_bootm.c Kernel subimage type OK
1829 -107 common/cmd_bootm.c Can't get kernel subimage data/size
1830 108 common/cmd_bootm.c Got kernel subimage data/size
1831 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
1832 -109 common/cmd_bootm.c Can't get kernel subimage type
1833 -110 common/cmd_bootm.c Can't get kernel subimage comp
1834 -111 common/cmd_bootm.c Can't get kernel subimage os
1835 -112 common/cmd_bootm.c Can't get kernel subimage load address
1836 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
1837
1838 120 common/image.c Start initial ramdisk verification
1839 -120 common/image.c Ramdisk FIT image has incorrect format
1840 121 common/image.c Ramdisk FIT image has correct format
1841 122 common/image.c No ramdisk subimage unit name, using configuration
1842 -122 common/image.c Can't get configuration for ramdisk subimage
1843 123 common/image.c Ramdisk unit name specified
1844 -124 common/image.c Can't get ramdisk subimage node offset
1845 125 common/image.c Got ramdisk subimage node offset
1846 -125 common/image.c Ramdisk subimage hash verification failed
1847 126 common/image.c Ramdisk subimage hash verification OK
1848 -126 common/image.c Ramdisk subimage for unsupported architecture
1849 127 common/image.c Architecture check OK
1850 -127 common/image.c Can't get ramdisk subimage data/size
1851 128 common/image.c Got ramdisk subimage data/size
1852 129 common/image.c Can't get ramdisk load address
1853 -129 common/image.c Got ramdisk load address
1854
1855 -130 common/cmd_doc.c Incorrect FIT image format
1856 131 common/cmd_doc.c FIT image format OK
1857
1858 -140 common/cmd_ide.c Incorrect FIT image format
1859 141 common/cmd_ide.c FIT image format OK
1860
1861 -150 common/cmd_nand.c Incorrect FIT image format
1862 151 common/cmd_nand.c FIT image format OK
1863
1864
1865 Modem Support:
1866 --------------
1867
1868 [so far only for SMDK2400 and TRAB boards]
1869
1870 - Modem support enable:
1871 CONFIG_MODEM_SUPPORT
1872
1873 - RTS/CTS Flow control enable:
1874 CONFIG_HWFLOW
1875
1876 - Modem debug support:
1877 CONFIG_MODEM_SUPPORT_DEBUG
1878
1879 Enables debugging stuff (char screen[1024], dbg())
1880 for modem support. Useful only with BDI2000.
1881
1882 - Interrupt support (PPC):
1883
1884 There are common interrupt_init() and timer_interrupt()
1885 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1886 for CPU specific initialization. interrupt_init_cpu()
1887 should set decrementer_count to appropriate value. If
1888 CPU resets decrementer automatically after interrupt
1889 (ppc4xx) it should set decrementer_count to zero.
1890 timer_interrupt() calls timer_interrupt_cpu() for CPU
1891 specific handling. If board has watchdog / status_led
1892 / other_activity_monitor it works automatically from
1893 general timer_interrupt().
1894
1895 - General:
1896
1897 In the target system modem support is enabled when a
1898 specific key (key combination) is pressed during
1899 power-on. Otherwise U-Boot will boot normally
1900 (autoboot). The key_pressed() function is called from
1901 board_init(). Currently key_pressed() is a dummy
1902 function, returning 1 and thus enabling modem
1903 initialization.
1904
1905 If there are no modem init strings in the
1906 environment, U-Boot proceed to autoboot; the
1907 previous output (banner, info printfs) will be
1908 suppressed, though.
1909
1910 See also: doc/README.Modem
1911
1912
1913 Configuration Settings:
1914 -----------------------
1915
1916 - CFG_LONGHELP: Defined when you want long help messages included;
1917 undefine this when you're short of memory.
1918
1919 - CFG_PROMPT: This is what U-Boot prints on the console to
1920 prompt for user input.
1921
1922 - CFG_CBSIZE: Buffer size for input from the Console
1923
1924 - CFG_PBSIZE: Buffer size for Console output
1925
1926 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1927
1928 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1929 the application (usually a Linux kernel) when it is
1930 booted
1931
1932 - CFG_BAUDRATE_TABLE:
1933 List of legal baudrate settings for this board.
1934
1935 - CFG_CONSOLE_INFO_QUIET
1936 Suppress display of console information at boot.
1937
1938 - CFG_CONSOLE_IS_IN_ENV
1939 If the board specific function
1940 extern int overwrite_console (void);
1941 returns 1, the stdin, stderr and stdout are switched to the
1942 serial port, else the settings in the environment are used.
1943
1944 - CFG_CONSOLE_OVERWRITE_ROUTINE
1945 Enable the call to overwrite_console().
1946
1947 - CFG_CONSOLE_ENV_OVERWRITE
1948 Enable overwrite of previous console environment settings.
1949
1950 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1951 Begin and End addresses of the area used by the
1952 simple memory test.
1953
1954 - CFG_ALT_MEMTEST:
1955 Enable an alternate, more extensive memory test.
1956
1957 - CFG_MEMTEST_SCRATCH:
1958 Scratch address used by the alternate memory test
1959 You only need to set this if address zero isn't writeable
1960
1961 - CFG_MEM_TOP_HIDE (PPC only):
1962 If CFG_MEM_TOP_HIDE is defined in the board config header,
1963 this specified memory area will get subtracted from the top
1964 (end) of RAM and won't get "touched" at all by U-Boot. By
1965 fixing up gd->ram_size the Linux kernel should gets passed
1966 the now "corrected" memory size and won't touch it either.
1967 This should work for arch/ppc and arch/powerpc. Only Linux
1968 board ports in arch/powerpc with bootwrapper support that
1969 recalculate the memory size from the SDRAM controller setup
1970 will have to get fixed in Linux additionally.
1971
1972 This option can be used as a workaround for the 440EPx/GRx
1973 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
1974 be touched.
1975
1976 WARNING: Please make sure that this value is a multiple of
1977 the Linux page size (normally 4k). If this is not the case,
1978 then the end address of the Linux memory will be located at a
1979 non page size aligned address and this could cause major
1980 problems.
1981
1982 - CFG_TFTP_LOADADDR:
1983 Default load address for network file downloads
1984
1985 - CFG_LOADS_BAUD_CHANGE:
1986 Enable temporary baudrate change while serial download
1987
1988 - CFG_SDRAM_BASE:
1989 Physical start address of SDRAM. _Must_ be 0 here.
1990
1991 - CFG_MBIO_BASE:
1992 Physical start address of Motherboard I/O (if using a
1993 Cogent motherboard)
1994
1995 - CFG_FLASH_BASE:
1996 Physical start address of Flash memory.
1997
1998 - CFG_MONITOR_BASE:
1999 Physical start address of boot monitor code (set by
2000 make config files to be same as the text base address
2001 (TEXT_BASE) used when linking) - same as
2002 CFG_FLASH_BASE when booting from flash.
2003
2004 - CFG_MONITOR_LEN:
2005 Size of memory reserved for monitor code, used to
2006 determine _at_compile_time_ (!) if the environment is
2007 embedded within the U-Boot image, or in a separate
2008 flash sector.
2009
2010 - CFG_MALLOC_LEN:
2011 Size of DRAM reserved for malloc() use.
2012
2013 - CFG_BOOTM_LEN:
2014 Normally compressed uImages are limited to an
2015 uncompressed size of 8 MBytes. If this is not enough,
2016 you can define CFG_BOOTM_LEN in your board config file
2017 to adjust this setting to your needs.
2018
2019 - CFG_BOOTMAPSZ:
2020 Maximum size of memory mapped by the startup code of
2021 the Linux kernel; all data that must be processed by
2022 the Linux kernel (bd_info, boot arguments, FDT blob if
2023 used) must be put below this limit, unless "bootm_low"
2024 enviroment variable is defined and non-zero. In such case
2025 all data for the Linux kernel must be between "bootm_low"
2026 and "bootm_low" + CFG_BOOTMAPSZ.
2027
2028 - CFG_MAX_FLASH_BANKS:
2029 Max number of Flash memory banks
2030
2031 - CFG_MAX_FLASH_SECT:
2032 Max number of sectors on a Flash chip
2033
2034 - CFG_FLASH_ERASE_TOUT:
2035 Timeout for Flash erase operations (in ms)
2036
2037 - CFG_FLASH_WRITE_TOUT:
2038 Timeout for Flash write operations (in ms)
2039
2040 - CFG_FLASH_LOCK_TOUT
2041 Timeout for Flash set sector lock bit operation (in ms)
2042
2043 - CFG_FLASH_UNLOCK_TOUT
2044 Timeout for Flash clear lock bits operation (in ms)
2045
2046 - CFG_FLASH_PROTECTION
2047 If defined, hardware flash sectors protection is used
2048 instead of U-Boot software protection.
2049
2050 - CFG_DIRECT_FLASH_TFTP:
2051
2052 Enable TFTP transfers directly to flash memory;
2053 without this option such a download has to be
2054 performed in two steps: (1) download to RAM, and (2)
2055 copy from RAM to flash.
2056
2057 The two-step approach is usually more reliable, since
2058 you can check if the download worked before you erase
2059 the flash, but in some situations (when system RAM is
2060 too limited to allow for a temporary copy of the
2061 downloaded image) this option may be very useful.
2062
2063 - CFG_FLASH_CFI:
2064 Define if the flash driver uses extra elements in the
2065 common flash structure for storing flash geometry.
2066
2067 - CONFIG_FLASH_CFI_DRIVER
2068 This option also enables the building of the cfi_flash driver
2069 in the drivers directory
2070
2071 - CFG_FLASH_USE_BUFFER_WRITE
2072 Use buffered writes to flash.
2073
2074 - CONFIG_FLASH_SPANSION_S29WS_N
2075 s29ws-n MirrorBit flash has non-standard addresses for buffered
2076 write commands.
2077
2078 - CFG_FLASH_QUIET_TEST
2079 If this option is defined, the common CFI flash doesn't
2080 print it's warning upon not recognized FLASH banks. This
2081 is useful, if some of the configured banks are only
2082 optionally available.
2083
2084 - CONFIG_FLASH_SHOW_PROGRESS
2085 If defined (must be an integer), print out countdown
2086 digits and dots. Recommended value: 45 (9..1) for 80
2087 column displays, 15 (3..1) for 40 column displays.
2088
2089 - CFG_RX_ETH_BUFFER:
2090 Defines the number of Ethernet receive buffers. On some
2091 Ethernet controllers it is recommended to set this value
2092 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2093 buffers can be full shortly after enabling the interface
2094 on high Ethernet traffic.
2095 Defaults to 4 if not defined.
2096
2097 The following definitions that deal with the placement and management
2098 of environment data (variable area); in general, we support the
2099 following configurations:
2100
2101 - CFG_ENV_IS_IN_FLASH:
2102
2103 Define this if the environment is in flash memory.
2104
2105 a) The environment occupies one whole flash sector, which is
2106 "embedded" in the text segment with the U-Boot code. This
2107 happens usually with "bottom boot sector" or "top boot
2108 sector" type flash chips, which have several smaller
2109 sectors at the start or the end. For instance, such a
2110 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2111 such a case you would place the environment in one of the
2112 4 kB sectors - with U-Boot code before and after it. With
2113 "top boot sector" type flash chips, you would put the
2114 environment in one of the last sectors, leaving a gap
2115 between U-Boot and the environment.
2116
2117 - CFG_ENV_OFFSET:
2118
2119 Offset of environment data (variable area) to the
2120 beginning of flash memory; for instance, with bottom boot
2121 type flash chips the second sector can be used: the offset
2122 for this sector is given here.
2123
2124 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
2125
2126 - CFG_ENV_ADDR:
2127
2128 This is just another way to specify the start address of
2129 the flash sector containing the environment (instead of
2130 CFG_ENV_OFFSET).
2131
2132 - CFG_ENV_SECT_SIZE:
2133
2134 Size of the sector containing the environment.
2135
2136
2137 b) Sometimes flash chips have few, equal sized, BIG sectors.
2138 In such a case you don't want to spend a whole sector for
2139 the environment.
2140
2141 - CFG_ENV_SIZE:
2142
2143 If you use this in combination with CFG_ENV_IS_IN_FLASH
2144 and CFG_ENV_SECT_SIZE, you can specify to use only a part
2145 of this flash sector for the environment. This saves
2146 memory for the RAM copy of the environment.
2147
2148 It may also save flash memory if you decide to use this
2149 when your environment is "embedded" within U-Boot code,
2150 since then the remainder of the flash sector could be used
2151 for U-Boot code. It should be pointed out that this is
2152 STRONGLY DISCOURAGED from a robustness point of view:
2153 updating the environment in flash makes it always
2154 necessary to erase the WHOLE sector. If something goes
2155 wrong before the contents has been restored from a copy in
2156 RAM, your target system will be dead.
2157
2158 - CFG_ENV_ADDR_REDUND
2159 CFG_ENV_SIZE_REDUND
2160
2161 These settings describe a second storage area used to hold
2162 a redundant copy of the environment data, so that there is
2163 a valid backup copy in case there is a power failure during
2164 a "saveenv" operation.
2165
2166 BE CAREFUL! Any changes to the flash layout, and some changes to the
2167 source code will make it necessary to adapt <board>/u-boot.lds*
2168 accordingly!
2169
2170
2171 - CFG_ENV_IS_IN_NVRAM:
2172
2173 Define this if you have some non-volatile memory device
2174 (NVRAM, battery buffered SRAM) which you want to use for the
2175 environment.
2176
2177 - CFG_ENV_ADDR:
2178 - CFG_ENV_SIZE:
2179
2180 These two #defines are used to determine the memory area you
2181 want to use for environment. It is assumed that this memory
2182 can just be read and written to, without any special
2183 provision.
2184
2185 BE CAREFUL! The first access to the environment happens quite early
2186 in U-Boot initalization (when we try to get the setting of for the
2187 console baudrate). You *MUST* have mapped your NVRAM area then, or
2188 U-Boot will hang.
2189
2190 Please note that even with NVRAM we still use a copy of the
2191 environment in RAM: we could work on NVRAM directly, but we want to
2192 keep settings there always unmodified except somebody uses "saveenv"
2193 to save the current settings.
2194
2195
2196 - CFG_ENV_IS_IN_EEPROM:
2197
2198 Use this if you have an EEPROM or similar serial access
2199 device and a driver for it.
2200
2201 - CFG_ENV_OFFSET:
2202 - CFG_ENV_SIZE:
2203
2204 These two #defines specify the offset and size of the
2205 environment area within the total memory of your EEPROM.
2206
2207 - CFG_I2C_EEPROM_ADDR:
2208 If defined, specified the chip address of the EEPROM device.
2209 The default address is zero.
2210
2211 - CFG_EEPROM_PAGE_WRITE_BITS:
2212 If defined, the number of bits used to address bytes in a
2213 single page in the EEPROM device. A 64 byte page, for example
2214 would require six bits.
2215
2216 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
2217 If defined, the number of milliseconds to delay between
2218 page writes. The default is zero milliseconds.
2219
2220 - CFG_I2C_EEPROM_ADDR_LEN:
2221 The length in bytes of the EEPROM memory array address. Note
2222 that this is NOT the chip address length!
2223
2224 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
2225 EEPROM chips that implement "address overflow" are ones
2226 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2227 address and the extra bits end up in the "chip address" bit
2228 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2229 byte chips.
2230
2231 Note that we consider the length of the address field to
2232 still be one byte because the extra address bits are hidden
2233 in the chip address.
2234
2235 - CFG_EEPROM_SIZE:
2236 The size in bytes of the EEPROM device.
2237
2238
2239 - CFG_ENV_IS_IN_DATAFLASH:
2240
2241 Define this if you have a DataFlash memory device which you
2242 want to use for the environment.
2243
2244 - CFG_ENV_OFFSET:
2245 - CFG_ENV_ADDR:
2246 - CFG_ENV_SIZE:
2247
2248 These three #defines specify the offset and size of the
2249 environment area within the total memory of your DataFlash placed
2250 at the specified address.
2251
2252 - CFG_ENV_IS_IN_NAND:
2253
2254 Define this if you have a NAND device which you want to use
2255 for the environment.
2256
2257 - CFG_ENV_OFFSET:
2258 - CFG_ENV_SIZE:
2259
2260 These two #defines specify the offset and size of the environment
2261 area within the first NAND device.
2262
2263 - CFG_ENV_OFFSET_REDUND
2264
2265 This setting describes a second storage area of CFG_ENV_SIZE
2266 size used to hold a redundant copy of the environment data,
2267 so that there is a valid backup copy in case there is a
2268 power failure during a "saveenv" operation.
2269
2270 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned
2271 to a block boundary, and CFG_ENV_SIZE must be a multiple of
2272 the NAND devices block size.
2273
2274 - CFG_SPI_INIT_OFFSET
2275
2276 Defines offset to the initial SPI buffer area in DPRAM. The
2277 area is used at an early stage (ROM part) if the environment
2278 is configured to reside in the SPI EEPROM: We need a 520 byte
2279 scratch DPRAM area. It is used between the two initialization
2280 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2281 to be a good choice since it makes it far enough from the
2282 start of the data area as well as from the stack pointer.
2283
2284 Please note that the environment is read-only until the monitor
2285 has been relocated to RAM and a RAM copy of the environment has been
2286 created; also, when using EEPROM you will have to use getenv_r()
2287 until then to read environment variables.
2288
2289 The environment is protected by a CRC32 checksum. Before the monitor
2290 is relocated into RAM, as a result of a bad CRC you will be working
2291 with the compiled-in default environment - *silently*!!! [This is
2292 necessary, because the first environment variable we need is the
2293 "baudrate" setting for the console - if we have a bad CRC, we don't
2294 have any device yet where we could complain.]
2295
2296 Note: once the monitor has been relocated, then it will complain if
2297 the default environment is used; a new CRC is computed as soon as you
2298 use the "saveenv" command to store a valid environment.
2299
2300 - CFG_FAULT_ECHO_LINK_DOWN:
2301 Echo the inverted Ethernet link state to the fault LED.
2302
2303 Note: If this option is active, then CFG_FAULT_MII_ADDR
2304 also needs to be defined.
2305
2306 - CFG_FAULT_MII_ADDR:
2307 MII address of the PHY to check for the Ethernet link state.
2308
2309 - CFG_64BIT_VSPRINTF:
2310 Makes vsprintf (and all *printf functions) support printing
2311 of 64bit values by using the L quantifier
2312
2313 - CFG_64BIT_STRTOUL:
2314 Adds simple_strtoull that returns a 64bit value
2315
2316 Low Level (hardware related) configuration options:
2317 ---------------------------------------------------
2318
2319 - CFG_CACHELINE_SIZE:
2320 Cache Line Size of the CPU.
2321
2322 - CFG_DEFAULT_IMMR:
2323 Default address of the IMMR after system reset.
2324
2325 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2326 and RPXsuper) to be able to adjust the position of
2327 the IMMR register after a reset.
2328
2329 - Floppy Disk Support:
2330 CFG_FDC_DRIVE_NUMBER
2331
2332 the default drive number (default value 0)
2333
2334 CFG_ISA_IO_STRIDE
2335
2336 defines the spacing between FDC chipset registers
2337 (default value 1)
2338
2339 CFG_ISA_IO_OFFSET
2340
2341 defines the offset of register from address. It
2342 depends on which part of the data bus is connected to
2343 the FDC chipset. (default value 0)
2344
2345 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
2346 CFG_FDC_DRIVE_NUMBER are undefined, they take their
2347 default value.
2348
2349 if CFG_FDC_HW_INIT is defined, then the function
2350 fdc_hw_init() is called at the beginning of the FDC
2351 setup. fdc_hw_init() must be provided by the board
2352 source code. It is used to make hardware dependant
2353 initializations.
2354
2355 - CFG_IMMR: Physical address of the Internal Memory.
2356 DO NOT CHANGE unless you know exactly what you're
2357 doing! (11-4) [MPC8xx/82xx systems only]
2358
2359 - CFG_INIT_RAM_ADDR:
2360
2361 Start address of memory area that can be used for
2362 initial data and stack; please note that this must be
2363 writable memory that is working WITHOUT special
2364 initialization, i. e. you CANNOT use normal RAM which
2365 will become available only after programming the
2366 memory controller and running certain initialization
2367 sequences.
2368
2369 U-Boot uses the following memory types:
2370 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2371 - MPC824X: data cache
2372 - PPC4xx: data cache
2373
2374 - CFG_GBL_DATA_OFFSET:
2375
2376 Offset of the initial data structure in the memory
2377 area defined by CFG_INIT_RAM_ADDR. Usually
2378 CFG_GBL_DATA_OFFSET is chosen such that the initial
2379 data is located at the end of the available space
2380 (sometimes written as (CFG_INIT_RAM_END -
2381 CFG_INIT_DATA_SIZE), and the initial stack is just
2382 below that area (growing from (CFG_INIT_RAM_ADDR +
2383 CFG_GBL_DATA_OFFSET) downward.
2384
2385 Note:
2386 On the MPC824X (or other systems that use the data
2387 cache for initial memory) the address chosen for
2388 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2389 point to an otherwise UNUSED address space between
2390 the top of RAM and the start of the PCI space.
2391
2392 - CFG_SIUMCR: SIU Module Configuration (11-6)
2393
2394 - CFG_SYPCR: System Protection Control (11-9)
2395
2396 - CFG_TBSCR: Time Base Status and Control (11-26)
2397
2398 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2399
2400 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2401
2402 - CFG_SCCR: System Clock and reset Control Register (15-27)
2403
2404 - CFG_OR_TIMING_SDRAM:
2405 SDRAM timing
2406
2407 - CFG_MAMR_PTA:
2408 periodic timer for refresh
2409
2410 - CFG_DER: Debug Event Register (37-47)
2411
2412 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2413 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2414 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2415 CFG_BR1_PRELIM:
2416 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2417
2418 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2419 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2420 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2421 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2422
2423 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2424 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2425 Machine Mode Register and Memory Periodic Timer
2426 Prescaler definitions (SDRAM timing)
2427
2428 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2429 enable I2C microcode relocation patch (MPC8xx);
2430 define relocation offset in DPRAM [DSP2]
2431
2432 - CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]:
2433 enable SMC microcode relocation patch (MPC8xx);
2434 define relocation offset in DPRAM [SMC1]
2435
2436 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2437 enable SPI microcode relocation patch (MPC8xx);
2438 define relocation offset in DPRAM [SCC4]
2439
2440 - CFG_USE_OSCCLK:
2441 Use OSCM clock mode on MBX8xx board. Be careful,
2442 wrong setting might damage your board. Read
2443 doc/README.MBX before setting this variable!
2444
2445 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2446 Offset of the bootmode word in DPRAM used by post
2447 (Power On Self Tests). This definition overrides
2448 #define'd default value in commproc.h resp.
2449 cpm_8260.h.
2450
2451 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2452 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2453 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2454 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2455 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2456 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2457 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2458 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2459 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2460
2461 - CONFIG_SPD_EEPROM
2462 Get DDR timing information from an I2C EEPROM. Common
2463 with pluggable memory modules such as SODIMMs
2464
2465 SPD_EEPROM_ADDRESS
2466 I2C address of the SPD EEPROM
2467
2468 - CFG_SPD_BUS_NUM
2469 If SPD EEPROM is on an I2C bus other than the first
2470 one, specify here. Note that the value must resolve
2471 to something your driver can deal with.
2472
2473 - CFG_83XX_DDR_USES_CS0
2474 Only for 83xx systems. If specified, then DDR should
2475 be configured using CS0 and CS1 instead of CS2 and CS3.
2476
2477 - CFG_83XX_DDR_USES_CS0
2478 Only for 83xx systems. If specified, then DDR should
2479 be configured using CS0 and CS1 instead of CS2 and CS3.
2480
2481 - CONFIG_ETHER_ON_FEC[12]
2482 Define to enable FEC[12] on a 8xx series processor.
2483
2484 - CONFIG_FEC[12]_PHY
2485 Define to the hardcoded PHY address which corresponds
2486 to the given FEC; i. e.
2487 #define CONFIG_FEC1_PHY 4
2488 means that the PHY with address 4 is connected to FEC1
2489
2490 When set to -1, means to probe for first available.
2491
2492 - CONFIG_FEC[12]_PHY_NORXERR
2493 The PHY does not have a RXERR line (RMII only).
2494 (so program the FEC to ignore it).
2495
2496 - CONFIG_RMII
2497 Enable RMII mode for all FECs.
2498 Note that this is a global option, we can't
2499 have one FEC in standard MII mode and another in RMII mode.
2500
2501 - CONFIG_CRC32_VERIFY
2502 Add a verify option to the crc32 command.
2503 The syntax is:
2504
2505 => crc32 -v <address> <count> <crc32>
2506
2507 Where address/count indicate a memory area
2508 and crc32 is the correct crc32 which the
2509 area should have.
2510
2511 - CONFIG_LOOPW
2512 Add the "loopw" memory command. This only takes effect if
2513 the memory commands are activated globally (CONFIG_CMD_MEM).
2514
2515 - CONFIG_MX_CYCLIC
2516 Add the "mdc" and "mwc" memory commands. These are cyclic
2517 "md/mw" commands.
2518 Examples:
2519
2520 => mdc.b 10 4 500
2521 This command will print 4 bytes (10,11,12,13) each 500 ms.
2522
2523 => mwc.l 100 12345678 10
2524 This command will write 12345678 to address 100 all 10 ms.
2525
2526 This only takes effect if the memory commands are activated
2527 globally (CONFIG_CMD_MEM).
2528
2529 - CONFIG_SKIP_LOWLEVEL_INIT
2530 - CONFIG_SKIP_RELOCATE_UBOOT
2531
2532 [ARM only] If these variables are defined, then
2533 certain low level initializations (like setting up
2534 the memory controller) are omitted and/or U-Boot does
2535 not relocate itself into RAM.
2536 Normally these variables MUST NOT be defined. The
2537 only exception is when U-Boot is loaded (to RAM) by
2538 some other boot loader or by a debugger which
2539 performs these initializations itself.
2540
2541
2542 Building the Software:
2543 ======================
2544
2545 Building U-Boot has been tested in several native build environments
2546 and in many different cross environments. Of course we cannot support
2547 all possibly existing versions of cross development tools in all
2548 (potentially obsolete) versions. In case of tool chain problems we
2549 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
2550 which is extensively used to build and test U-Boot.
2551
2552 If you are not using a native environment, it is assumed that you
2553 have GNU cross compiling tools available in your path. In this case,
2554 you must set the environment variable CROSS_COMPILE in your shell.
2555 Note that no changes to the Makefile or any other source files are
2556 necessary. For example using the ELDK on a 4xx CPU, please enter:
2557
2558 $ CROSS_COMPILE=ppc_4xx-
2559 $ export CROSS_COMPILE
2560
2561 U-Boot is intended to be simple to build. After installing the
2562 sources you must configure U-Boot for one specific board type. This
2563 is done by typing:
2564
2565 make NAME_config
2566
2567 where "NAME_config" is the name of one of the existing configu-
2568 rations; see the main Makefile for supported names.
2569
2570 Note: for some board special configuration names may exist; check if
2571 additional information is available from the board vendor; for
2572 instance, the TQM823L systems are available without (standard)
2573 or with LCD support. You can select such additional "features"
2574 when choosing the configuration, i. e.
2575
2576 make TQM823L_config
2577 - will configure for a plain TQM823L, i. e. no LCD support
2578
2579 make TQM823L_LCD_config
2580 - will configure for a TQM823L with U-Boot console on LCD
2581
2582 etc.
2583
2584
2585 Finally, type "make all", and you should get some working U-Boot
2586 images ready for download to / installation on your system:
2587
2588 - "u-boot.bin" is a raw binary image
2589 - "u-boot" is an image in ELF binary format
2590 - "u-boot.srec" is in Motorola S-Record format
2591
2592 By default the build is performed locally and the objects are saved
2593 in the source directory. One of the two methods can be used to change
2594 this behavior and build U-Boot to some external directory:
2595
2596 1. Add O= to the make command line invocations:
2597
2598 make O=/tmp/build distclean
2599 make O=/tmp/build NAME_config
2600 make O=/tmp/build all
2601
2602 2. Set environment variable BUILD_DIR to point to the desired location:
2603
2604 export BUILD_DIR=/tmp/build
2605 make distclean
2606 make NAME_config
2607 make all
2608
2609 Note that the command line "O=" setting overrides the BUILD_DIR environment
2610 variable.
2611
2612
2613 Please be aware that the Makefiles assume you are using GNU make, so
2614 for instance on NetBSD you might need to use "gmake" instead of
2615 native "make".
2616
2617
2618 If the system board that you have is not listed, then you will need
2619 to port U-Boot to your hardware platform. To do this, follow these
2620 steps:
2621
2622 1. Add a new configuration option for your board to the toplevel
2623 "Makefile" and to the "MAKEALL" script, using the existing
2624 entries as examples. Note that here and at many other places
2625 boards and other names are listed in alphabetical sort order. Please
2626 keep this order.
2627 2. Create a new directory to hold your board specific code. Add any
2628 files you need. In your board directory, you will need at least
2629 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2630 3. Create a new configuration file "include/configs/<board>.h" for
2631 your board
2632 3. If you're porting U-Boot to a new CPU, then also create a new
2633 directory to hold your CPU specific code. Add any files you need.
2634 4. Run "make <board>_config" with your new name.
2635 5. Type "make", and you should get a working "u-boot.srec" file
2636 to be installed on your target system.
2637 6. Debug and solve any problems that might arise.
2638 [Of course, this last step is much harder than it sounds.]
2639
2640
2641 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2642 ==============================================================
2643
2644 If you have modified U-Boot sources (for instance added a new board
2645 or support for new devices, a new CPU, etc.) you are expected to
2646 provide feedback to the other developers. The feedback normally takes
2647 the form of a "patch", i. e. a context diff against a certain (latest
2648 official or latest in the git repository) version of U-Boot sources.
2649
2650 But before you submit such a patch, please verify that your modifi-
2651 cation did not break existing code. At least make sure that *ALL* of
2652 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2653 just run the "MAKEALL" script, which will configure and build U-Boot
2654 for ALL supported system. Be warned, this will take a while. You can
2655 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2656 environment variable to the script, i. e. to use the ELDK cross tools
2657 you can type
2658
2659 CROSS_COMPILE=ppc_8xx- MAKEALL
2660
2661 or to build on a native PowerPC system you can type
2662
2663 CROSS_COMPILE=' ' MAKEALL
2664
2665 When using the MAKEALL script, the default behaviour is to build
2666 U-Boot in the source directory. This location can be changed by
2667 setting the BUILD_DIR environment variable. Also, for each target
2668 built, the MAKEALL script saves two log files (<target>.ERR and
2669 <target>.MAKEALL) in the <source dir>/LOG directory. This default
2670 location can be changed by setting the MAKEALL_LOGDIR environment
2671 variable. For example:
2672
2673 export BUILD_DIR=/tmp/build
2674 export MAKEALL_LOGDIR=/tmp/log
2675 CROSS_COMPILE=ppc_8xx- MAKEALL
2676
2677 With the above settings build objects are saved in the /tmp/build,
2678 log files are saved in the /tmp/log and the source tree remains clean
2679 during the whole build process.
2680
2681
2682 See also "U-Boot Porting Guide" below.
2683
2684
2685 Monitor Commands - Overview:
2686 ============================
2687
2688 go - start application at address 'addr'
2689 run - run commands in an environment variable
2690 bootm - boot application image from memory
2691 bootp - boot image via network using BootP/TFTP protocol
2692 tftpboot- boot image via network using TFTP protocol
2693 and env variables "ipaddr" and "serverip"
2694 (and eventually "gatewayip")
2695 rarpboot- boot image via network using RARP/TFTP protocol
2696 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2697 loads - load S-Record file over serial line
2698 loadb - load binary file over serial line (kermit mode)
2699 md - memory display
2700 mm - memory modify (auto-incrementing)
2701 nm - memory modify (constant address)
2702 mw - memory write (fill)
2703 cp - memory copy
2704 cmp - memory compare
2705 crc32 - checksum calculation
2706 imd - i2c memory display
2707 imm - i2c memory modify (auto-incrementing)
2708 inm - i2c memory modify (constant address)
2709 imw - i2c memory write (fill)
2710 icrc32 - i2c checksum calculation
2711 iprobe - probe to discover valid I2C chip addresses
2712 iloop - infinite loop on address range
2713 isdram - print SDRAM configuration information
2714 sspi - SPI utility commands
2715 base - print or set address offset
2716 printenv- print environment variables
2717 setenv - set environment variables
2718 saveenv - save environment variables to persistent storage
2719 protect - enable or disable FLASH write protection
2720 erase - erase FLASH memory
2721 flinfo - print FLASH memory information
2722 bdinfo - print Board Info structure
2723 iminfo - print header information for application image
2724 coninfo - print console devices and informations
2725 ide - IDE sub-system
2726 loop - infinite loop on address range
2727 loopw - infinite write loop on address range
2728 mtest - simple RAM test
2729 icache - enable or disable instruction cache
2730 dcache - enable or disable data cache
2731 reset - Perform RESET of the CPU
2732 echo - echo args to console
2733 version - print monitor version
2734 help - print online help
2735 ? - alias for 'help'
2736
2737
2738 Monitor Commands - Detailed Description:
2739 ========================================
2740
2741 TODO.
2742
2743 For now: just type "help <command>".
2744
2745
2746 Environment Variables:
2747 ======================
2748
2749 U-Boot supports user configuration using Environment Variables which
2750 can be made persistent by saving to Flash memory.
2751
2752 Environment Variables are set using "setenv", printed using
2753 "printenv", and saved to Flash using "saveenv". Using "setenv"
2754 without a value can be used to delete a variable from the
2755 environment. As long as you don't save the environment you are
2756 working with an in-memory copy. In case the Flash area containing the
2757 environment is erased by accident, a default environment is provided.
2758
2759 Some configuration options can be set using Environment Variables:
2760
2761 baudrate - see CONFIG_BAUDRATE
2762
2763 bootdelay - see CONFIG_BOOTDELAY
2764
2765 bootcmd - see CONFIG_BOOTCOMMAND
2766
2767 bootargs - Boot arguments when booting an RTOS image
2768
2769 bootfile - Name of the image to load with TFTP
2770
2771 bootm_low - Memory range available for image processing in the bootm
2772 command can be restricted. This variable is given as
2773 a hexadecimal number and defines lowest address allowed
2774 for use by the bootm command. See also "bootm_size"
2775 environment variable. Address defined by "bootm_low" is
2776 also the base of the initial memory mapping for the Linux
2777 kernel -- see the description of CFG_BOOTMAPSZ.
2778
2779 bootm_size - Memory range available for image processing in the bootm
2780 command can be restricted. This variable is given as
2781 a hexadecimal number and defines the size of the region
2782 allowed for use by the bootm command. See also "bootm_low"
2783 environment variable.
2784
2785 autoload - if set to "no" (any string beginning with 'n'),
2786 "bootp" will just load perform a lookup of the
2787 configuration from the BOOTP server, but not try to
2788 load any image using TFTP
2789
2790 autoscript - if set to "yes" commands like "loadb", "loady",
2791 "bootp", "tftpb", "rarpboot" and "nfs" will attempt
2792 to automatically run script images (by internally
2793 calling "autoscript").
2794
2795 autoscript_uname - if script image is in a format (FIT) this
2796 variable is used to get script subimage unit name.
2797
2798 autostart - if set to "yes", an image loaded using the "bootp",
2799 "rarpboot", "tftpboot" or "diskboot" commands will
2800 be automatically started (by internally calling
2801 "bootm")
2802
2803 If set to "no", a standalone image passed to the
2804 "bootm" command will be copied to the load address
2805 (and eventually uncompressed), but NOT be started.
2806 This can be used to load and uncompress arbitrary
2807 data.
2808
2809 i2cfast - (PPC405GP|PPC405EP only)
2810 if set to 'y' configures Linux I2C driver for fast
2811 mode (400kHZ). This environment variable is used in
2812 initialization code. So, for changes to be effective
2813 it must be saved and board must be reset.
2814
2815 initrd_high - restrict positioning of initrd images:
2816 If this variable is not set, initrd images will be
2817 copied to the highest possible address in RAM; this
2818 is usually what you want since it allows for
2819 maximum initrd size. If for some reason you want to
2820 make sure that the initrd image is loaded below the
2821 CFG_BOOTMAPSZ limit, you can set this environment
2822 variable to a value of "no" or "off" or "0".
2823 Alternatively, you can set it to a maximum upper
2824 address to use (U-Boot will still check that it
2825 does not overwrite the U-Boot stack and data).
2826
2827 For instance, when you have a system with 16 MB
2828 RAM, and want to reserve 4 MB from use by Linux,
2829 you can do this by adding "mem=12M" to the value of
2830 the "bootargs" variable. However, now you must make
2831 sure that the initrd image is placed in the first
2832 12 MB as well - this can be done with
2833
2834 setenv initrd_high 00c00000
2835
2836 If you set initrd_high to 0xFFFFFFFF, this is an
2837 indication to U-Boot that all addresses are legal
2838 for the Linux kernel, including addresses in flash
2839 memory. In this case U-Boot will NOT COPY the
2840 ramdisk at all. This may be useful to reduce the
2841 boot time on your system, but requires that this
2842 feature is supported by your Linux kernel.
2843
2844 ipaddr - IP address; needed for tftpboot command
2845
2846 loadaddr - Default load address for commands like "bootp",
2847 "rarpboot", "tftpboot", "loadb" or "diskboot"
2848
2849 loads_echo - see CONFIG_LOADS_ECHO
2850
2851 serverip - TFTP server IP address; needed for tftpboot command
2852
2853 bootretry - see CONFIG_BOOT_RETRY_TIME
2854
2855 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2856
2857 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2858
2859 ethprime - When CONFIG_NET_MULTI is enabled controls which
2860 interface is used first.
2861
2862 ethact - When CONFIG_NET_MULTI is enabled controls which
2863 interface is currently active. For example you
2864 can do the following
2865
2866 => setenv ethact FEC ETHERNET
2867 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2868 => setenv ethact SCC ETHERNET
2869 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2870
2871 ethrotate - When set to "no" U-Boot does not go through all
2872 available network interfaces.
2873 It just stays at the currently selected interface.
2874
2875 netretry - When set to "no" each network operation will
2876 either succeed or fail without retrying.
2877 When set to "once" the network operation will
2878 fail when all the available network interfaces
2879 are tried once without success.
2880 Useful on scripts which control the retry operation
2881 themselves.
2882
2883 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD
2884 if set load address for the NPE microcode
2885
2886 tftpsrcport - If this is set, the value is used for TFTP's
2887 UDP source port.
2888
2889 tftpdstport - If this is set, the value is used for TFTP's UDP
2890 destination port instead of the Well Know Port 69.
2891
2892 vlan - When set to a value < 4095 the traffic over
2893 Ethernet is encapsulated/received over 802.1q
2894 VLAN tagged frames.
2895
2896 The following environment variables may be used and automatically
2897 updated by the network boot commands ("bootp" and "rarpboot"),
2898 depending the information provided by your boot server:
2899
2900 bootfile - see above
2901 dnsip - IP address of your Domain Name Server
2902 dnsip2 - IP address of your secondary Domain Name Server
2903 gatewayip - IP address of the Gateway (Router) to use
2904 hostname - Target hostname
2905 ipaddr - see above
2906 netmask - Subnet Mask
2907 rootpath - Pathname of the root filesystem on the NFS server
2908 serverip - see above
2909
2910
2911 There are two special Environment Variables:
2912
2913 serial# - contains hardware identification information such
2914 as type string and/or serial number
2915 ethaddr - Ethernet address
2916
2917 These variables can be set only once (usually during manufacturing of
2918 the board). U-Boot refuses to delete or overwrite these variables
2919 once they have been set once.
2920
2921
2922 Further special Environment Variables:
2923
2924 ver - Contains the U-Boot version string as printed
2925 with the "version" command. This variable is
2926 readonly (see CONFIG_VERSION_VARIABLE).
2927
2928
2929 Please note that changes to some configuration parameters may take
2930 only effect after the next boot (yes, that's just like Windoze :-).
2931
2932
2933 Command Line Parsing:
2934 =====================
2935
2936 There are two different command line parsers available with U-Boot:
2937 the old "simple" one, and the much more powerful "hush" shell:
2938
2939 Old, simple command line parser:
2940 --------------------------------
2941
2942 - supports environment variables (through setenv / saveenv commands)
2943 - several commands on one line, separated by ';'
2944 - variable substitution using "... ${name} ..." syntax
2945 - special characters ('$', ';') can be escaped by prefixing with '\',
2946 for example:
2947 setenv bootcmd bootm \${address}
2948 - You can also escape text by enclosing in single apostrophes, for example:
2949 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2950
2951 Hush shell:
2952 -----------
2953
2954 - similar to Bourne shell, with control structures like
2955 if...then...else...fi, for...do...done; while...do...done,
2956 until...do...done, ...
2957 - supports environment ("global") variables (through setenv / saveenv
2958 commands) and local shell variables (through standard shell syntax
2959 "name=value"); only environment variables can be used with "run"
2960 command
2961
2962 General rules:
2963 --------------
2964
2965 (1) If a command line (or an environment variable executed by a "run"
2966 command) contains several commands separated by semicolon, and
2967 one of these commands fails, then the remaining commands will be
2968 executed anyway.
2969
2970 (2) If you execute several variables with one call to run (i. e.
2971 calling run with a list of variables as arguments), any failing
2972 command will cause "run" to terminate, i. e. the remaining
2973 variables are not executed.
2974
2975 Note for Redundant Ethernet Interfaces:
2976 =======================================
2977
2978 Some boards come with redundant Ethernet interfaces; U-Boot supports
2979 such configurations and is capable of automatic selection of a
2980 "working" interface when needed. MAC assignment works as follows:
2981
2982 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2983 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2984 "eth1addr" (=>eth1), "eth2addr", ...
2985
2986 If the network interface stores some valid MAC address (for instance
2987 in SROM), this is used as default address if there is NO correspon-
2988 ding setting in the environment; if the corresponding environment
2989 variable is set, this overrides the settings in the card; that means:
2990
2991 o If the SROM has a valid MAC address, and there is no address in the
2992 environment, the SROM's address is used.
2993
2994 o If there is no valid address in the SROM, and a definition in the
2995 environment exists, then the value from the environment variable is
2996 used.
2997
2998 o If both the SROM and the environment contain a MAC address, and
2999 both addresses are the same, this MAC address is used.
3000
3001 o If both the SROM and the environment contain a MAC address, and the
3002 addresses differ, the value from the environment is used and a
3003 warning is printed.
3004
3005 o If neither SROM nor the environment contain a MAC address, an error
3006 is raised.
3007
3008
3009 Image Formats:
3010 ==============
3011
3012 U-Boot is capable of booting (and performing other auxiliary operations on)
3013 images in two formats:
3014
3015 New uImage format (FIT)
3016 -----------------------
3017
3018 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3019 to Flattened Device Tree). It allows the use of images with multiple
3020 components (several kernels, ramdisks, etc.), with contents protected by
3021 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3022
3023
3024 Old uImage format
3025 -----------------
3026
3027 Old image format is based on binary files which can be basically anything,
3028 preceded by a special header; see the definitions in include/image.h for
3029 details; basically, the header defines the following image properties:
3030
3031 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3032 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3033 LynxOS, pSOS, QNX, RTEMS, ARTOS;
3034 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
3035 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3036 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3037 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
3038 * Compression Type (uncompressed, gzip, bzip2)
3039 * Load Address
3040 * Entry Point
3041 * Image Name
3042 * Image Timestamp
3043
3044 The header is marked by a special Magic Number, and both the header
3045 and the data portions of the image are secured against corruption by
3046 CRC32 checksums.
3047
3048
3049 Linux Support:
3050 ==============
3051
3052 Although U-Boot should support any OS or standalone application
3053 easily, the main focus has always been on Linux during the design of
3054 U-Boot.
3055
3056 U-Boot includes many features that so far have been part of some
3057 special "boot loader" code within the Linux kernel. Also, any
3058 "initrd" images to be used are no longer part of one big Linux image;
3059 instead, kernel and "initrd" are separate images. This implementation
3060 serves several purposes:
3061
3062 - the same features can be used for other OS or standalone
3063 applications (for instance: using compressed images to reduce the
3064 Flash memory footprint)
3065
3066 - it becomes much easier to port new Linux kernel versions because
3067 lots of low-level, hardware dependent stuff are done by U-Boot
3068
3069 - the same Linux kernel image can now be used with different "initrd"
3070 images; of course this also means that different kernel images can
3071 be run with the same "initrd". This makes testing easier (you don't
3072 have to build a new "zImage.initrd" Linux image when you just
3073 change a file in your "initrd"). Also, a field-upgrade of the
3074 software is easier now.
3075
3076
3077 Linux HOWTO:
3078 ============
3079
3080 Porting Linux to U-Boot based systems:
3081 ---------------------------------------
3082
3083 U-Boot cannot save you from doing all the necessary modifications to
3084 configure the Linux device drivers for use with your target hardware
3085 (no, we don't intend to provide a full virtual machine interface to
3086 Linux :-).
3087
3088 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
3089
3090 Just make sure your machine specific header file (for instance
3091 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3092 Information structure as we define in include/u-boot.h, and make
3093 sure that your definition of IMAP_ADDR uses the same value as your
3094 U-Boot configuration in CFG_IMMR.
3095
3096
3097 Configuring the Linux kernel:
3098 -----------------------------
3099
3100 No specific requirements for U-Boot. Make sure you have some root
3101 device (initial ramdisk, NFS) for your target system.
3102
3103
3104 Building a Linux Image:
3105 -----------------------
3106
3107 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3108 not used. If you use recent kernel source, a new build target
3109 "uImage" will exist which automatically builds an image usable by
3110 U-Boot. Most older kernels also have support for a "pImage" target,
3111 which was introduced for our predecessor project PPCBoot and uses a
3112 100% compatible format.
3113
3114 Example:
3115
3116 make TQM850L_config
3117 make oldconfig
3118 make dep
3119 make uImage
3120
3121 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3122 encapsulate a compressed Linux kernel image with header information,
3123 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3124
3125 * build a standard "vmlinux" kernel image (in ELF binary format):
3126
3127 * convert the kernel into a raw binary image:
3128
3129 ${CROSS_COMPILE}-objcopy -O binary \
3130 -R .note -R .comment \
3131 -S vmlinux linux.bin
3132
3133 * compress the binary image:
3134
3135 gzip -9 linux.bin
3136
3137 * package compressed binary image for U-Boot:
3138
3139 mkimage -A ppc -O linux -T kernel -C gzip \
3140 -a 0 -e 0 -n "Linux Kernel Image" \
3141 -d linux.bin.gz uImage
3142
3143
3144 The "mkimage" tool can also be used to create ramdisk images for use
3145 with U-Boot, either separated from the Linux kernel image, or
3146 combined into one file. "mkimage" encapsulates the images with a 64
3147 byte header containing information about target architecture,
3148 operating system, image type, compression method, entry points, time
3149 stamp, CRC32 checksums, etc.
3150
3151 "mkimage" can be called in two ways: to verify existing images and
3152 print the header information, or to build new images.
3153
3154 In the first form (with "-l" option) mkimage lists the information
3155 contained in the header of an existing U-Boot image; this includes
3156 checksum verification:
3157
3158 tools/mkimage -l image
3159 -l ==> list image header information
3160
3161 The second form (with "-d" option) is used to build a U-Boot image
3162 from a "data file" which is used as image payload:
3163
3164 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3165 -n name -d data_file image
3166 -A ==> set architecture to 'arch'
3167 -O ==> set operating system to 'os'
3168 -T ==> set image type to 'type'
3169 -C ==> set compression type 'comp'
3170 -a ==> set load address to 'addr' (hex)
3171 -e ==> set entry point to 'ep' (hex)
3172 -n ==> set image name to 'name'
3173 -d ==> use image data from 'datafile'
3174
3175 Right now, all Linux kernels for PowerPC systems use the same load
3176 address (0x00000000), but the entry point address depends on the
3177 kernel version:
3178
3179 - 2.2.x kernels have the entry point at 0x0000000C,
3180 - 2.3.x and later kernels have the entry point at 0x00000000.
3181
3182 So a typical call to build a U-Boot image would read:
3183
3184 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3185 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3186 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
3187 > examples/uImage.TQM850L
3188 Image Name: 2.4.4 kernel for TQM850L
3189 Created: Wed Jul 19 02:34:59 2000
3190 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3191 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3192 Load Address: 0x00000000
3193 Entry Point: 0x00000000
3194
3195 To verify the contents of the image (or check for corruption):
3196
3197 -> tools/mkimage -l examples/uImage.TQM850L
3198 Image Name: 2.4.4 kernel for TQM850L
3199 Created: Wed Jul 19 02:34:59 2000
3200 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3201 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3202 Load Address: 0x00000000
3203 Entry Point: 0x00000000
3204
3205 NOTE: for embedded systems where boot time is critical you can trade
3206 speed for memory and install an UNCOMPRESSED image instead: this
3207 needs more space in Flash, but boots much faster since it does not
3208 need to be uncompressed:
3209
3210 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
3211 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3212 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3213 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
3214 > examples/uImage.TQM850L-uncompressed
3215 Image Name: 2.4.4 kernel for TQM850L
3216 Created: Wed Jul 19 02:34:59 2000
3217 Image Type: PowerPC Linux Kernel Image (uncompressed)
3218 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3219 Load Address: 0x00000000
3220 Entry Point: 0x00000000
3221
3222
3223 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3224 when your kernel is intended to use an initial ramdisk:
3225
3226 -> tools/mkimage -n 'Simple Ramdisk Image' \
3227 > -A ppc -O linux -T ramdisk -C gzip \
3228 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3229 Image Name: Simple Ramdisk Image
3230 Created: Wed Jan 12 14:01:50 2000
3231 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3232 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3233 Load Address: 0x00000000
3234 Entry Point: 0x00000000
3235
3236
3237 Installing a Linux Image:
3238 -------------------------
3239
3240 To downloading a U-Boot image over the serial (console) interface,
3241 you must convert the image to S-Record format:
3242
3243 objcopy -I binary -O srec examples/image examples/image.srec
3244
3245 The 'objcopy' does not understand the information in the U-Boot
3246 image header, so the resulting S-Record file will be relative to
3247 address 0x00000000. To load it to a given address, you need to
3248 specify the target address as 'offset' parameter with the 'loads'
3249 command.
3250
3251 Example: install the image to address 0x40100000 (which on the
3252 TQM8xxL is in the first Flash bank):
3253
3254 => erase 40100000 401FFFFF
3255
3256 .......... done
3257 Erased 8 sectors
3258
3259 => loads 40100000
3260 ## Ready for S-Record download ...
3261 ~>examples/image.srec
3262 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3263 ...
3264 15989 15990 15991 15992
3265 [file transfer complete]
3266 [connected]
3267 ## Start Addr = 0x00000000
3268
3269
3270 You can check the success of the download using the 'iminfo' command;
3271 this includes a checksum verification so you can be sure no data
3272 corruption happened:
3273
3274 => imi 40100000
3275
3276 ## Checking Image at 40100000 ...
3277 Image Name: 2.2.13 for initrd on TQM850L
3278 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3279 Data Size: 335725 Bytes = 327 kB = 0 MB
3280 Load Address: 00000000
3281 Entry Point: 0000000c
3282 Verifying Checksum ... OK
3283
3284
3285 Boot Linux:
3286 -----------
3287
3288 The "bootm" command is used to boot an application that is stored in
3289 memory (RAM or Flash). In case of a Linux kernel image, the contents
3290 of the "bootargs" environment variable is passed to the kernel as
3291 parameters. You can check and modify this variable using the
3292 "printenv" and "setenv" commands:
3293
3294
3295 => printenv bootargs
3296 bootargs=root=/dev/ram
3297
3298 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3299
3300 => printenv bootargs
3301 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3302
3303 => bootm 40020000
3304 ## Booting Linux kernel at 40020000 ...
3305 Image Name: 2.2.13 for NFS on TQM850L
3306 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3307 Data Size: 381681 Bytes = 372 kB = 0 MB
3308 Load Address: 00000000
3309 Entry Point: 0000000c
3310 Verifying Checksum ... OK
3311 Uncompressing Kernel Image ... OK
3312 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
3313 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3314 time_init: decrementer frequency = 187500000/60
3315 Calibrating delay loop... 49.77 BogoMIPS
3316 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3317 ...
3318
3319 If you want to boot a Linux kernel with initial RAM disk, you pass
3320 the memory addresses of both the kernel and the initrd image (PPBCOOT
3321 format!) to the "bootm" command:
3322
3323 => imi 40100000 40200000
3324
3325 ## Checking Image at 40100000 ...
3326 Image Name: 2.2.13 for initrd on TQM850L
3327 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3328 Data Size: 335725 Bytes = 327 kB = 0 MB
3329 Load Address: 00000000
3330 Entry Point: 0000000c
3331 Verifying Checksum ... OK
3332
3333 ## Checking Image at 40200000 ...
3334 Image Name: Simple Ramdisk Image
3335 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3336 Data Size: 566530 Bytes = 553 kB = 0 MB
3337 Load Address: 00000000
3338 Entry Point: 00000000
3339 Verifying Checksum ... OK
3340
3341 => bootm 40100000 40200000
3342 ## Booting Linux kernel at 40100000 ...
3343 Image Name: 2.2.13 for initrd on TQM850L
3344 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3345 Data Size: 335725 Bytes = 327 kB = 0 MB
3346 Load Address: 00000000
3347 Entry Point: 0000000c
3348 Verifying Checksum ... OK
3349 Uncompressing Kernel Image ... OK
3350 ## Loading RAMDisk Image at 40200000 ...
3351 Image Name: Simple Ramdisk Image
3352 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3353 Data Size: 566530 Bytes = 553 kB = 0 MB
3354 Load Address: 00000000
3355 Entry Point: 00000000
3356 Verifying Checksum ... OK
3357 Loading Ramdisk ... OK
3358 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
3359 Boot arguments: root=/dev/ram
3360 time_init: decrementer frequency = 187500000/60
3361 Calibrating delay loop... 49.77 BogoMIPS
3362 ...
3363 RAMDISK: Compressed image found at block 0
3364 VFS: Mounted root (ext2 filesystem).
3365
3366 bash#
3367
3368 Boot Linux and pass a flat device tree:
3369 -----------
3370
3371 First, U-Boot must be compiled with the appropriate defines. See the section
3372 titled "Linux Kernel Interface" above for a more in depth explanation. The
3373 following is an example of how to start a kernel and pass an updated
3374 flat device tree:
3375
3376 => print oftaddr
3377 oftaddr=0x300000
3378 => print oft
3379 oft=oftrees/mpc8540ads.dtb
3380 => tftp $oftaddr $oft
3381 Speed: 1000, full duplex
3382 Using TSEC0 device
3383 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3384 Filename 'oftrees/mpc8540ads.dtb'.
3385 Load address: 0x300000
3386 Loading: #
3387 done
3388 Bytes transferred = 4106 (100a hex)
3389 => tftp $loadaddr $bootfile
3390 Speed: 1000, full duplex
3391 Using TSEC0 device
3392 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3393 Filename 'uImage'.
3394 Load address: 0x200000
3395 Loading:############
3396 done
3397 Bytes transferred = 1029407 (fb51f hex)
3398 => print loadaddr
3399 loadaddr=200000
3400 => print oftaddr
3401 oftaddr=0x300000
3402 => bootm $loadaddr - $oftaddr
3403 ## Booting image at 00200000 ...
3404 Image Name: Linux-2.6.17-dirty
3405 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3406 Data Size: 1029343 Bytes = 1005.2 kB
3407 Load Address: 00000000
3408 Entry Point: 00000000
3409 Verifying Checksum ... OK
3410 Uncompressing Kernel Image ... OK
3411 Booting using flat device tree at 0x300000
3412 Using MPC85xx ADS machine description
3413 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3414 [snip]
3415
3416
3417 More About U-Boot Image Types:
3418 ------------------------------
3419
3420 U-Boot supports the following image types:
3421
3422 "Standalone Programs" are directly runnable in the environment
3423 provided by U-Boot; it is expected that (if they behave
3424 well) you can continue to work in U-Boot after return from
3425 the Standalone Program.
3426 "OS Kernel Images" are usually images of some Embedded OS which
3427 will take over control completely. Usually these programs
3428 will install their own set of exception handlers, device
3429 drivers, set up the MMU, etc. - this means, that you cannot
3430 expect to re-enter U-Boot except by resetting the CPU.
3431 "RAMDisk Images" are more or less just data blocks, and their
3432 parameters (address, size) are passed to an OS kernel that is
3433 being started.
3434 "Multi-File Images" contain several images, typically an OS
3435 (Linux) kernel image and one or more data images like
3436 RAMDisks. This construct is useful for instance when you want
3437 to boot over the network using BOOTP etc., where the boot
3438 server provides just a single image file, but you want to get
3439 for instance an OS kernel and a RAMDisk image.
3440
3441 "Multi-File Images" start with a list of image sizes, each
3442 image size (in bytes) specified by an "uint32_t" in network
3443 byte order. This list is terminated by an "(uint32_t)0".
3444 Immediately after the terminating 0 follow the images, one by
3445 one, all aligned on "uint32_t" boundaries (size rounded up to
3446 a multiple of 4 bytes).
3447
3448 "Firmware Images" are binary images containing firmware (like
3449 U-Boot or FPGA images) which usually will be programmed to
3450 flash memory.
3451
3452 "Script files" are command sequences that will be executed by
3453 U-Boot's command interpreter; this feature is especially
3454 useful when you configure U-Boot to use a real shell (hush)
3455 as command interpreter.
3456
3457
3458 Standalone HOWTO:
3459 =================
3460
3461 One of the features of U-Boot is that you can dynamically load and
3462 run "standalone" applications, which can use some resources of
3463 U-Boot like console I/O functions or interrupt services.
3464
3465 Two simple examples are included with the sources:
3466
3467 "Hello World" Demo:
3468 -------------------
3469
3470 'examples/hello_world.c' contains a small "Hello World" Demo
3471 application; it is automatically compiled when you build U-Boot.
3472 It's configured to run at address 0x00040004, so you can play with it
3473 like that:
3474
3475 => loads
3476 ## Ready for S-Record download ...
3477 ~>examples/hello_world.srec
3478 1 2 3 4 5 6 7 8 9 10 11 ...
3479 [file transfer complete]
3480 [connected]
3481 ## Start Addr = 0x00040004
3482
3483 => go 40004 Hello World! This is a test.
3484 ## Starting application at 0x00040004 ...
3485 Hello World
3486 argc = 7
3487 argv[0] = "40004"
3488 argv[1] = "Hello"
3489 argv[2] = "World!"
3490 argv[3] = "This"
3491 argv[4] = "is"
3492 argv[5] = "a"
3493 argv[6] = "test."
3494 argv[7] = "<NULL>"
3495 Hit any key to exit ...
3496
3497 ## Application terminated, rc = 0x0
3498
3499 Another example, which demonstrates how to register a CPM interrupt
3500 handler with the U-Boot code, can be found in 'examples/timer.c'.
3501 Here, a CPM timer is set up to generate an interrupt every second.
3502 The interrupt service routine is trivial, just printing a '.'
3503 character, but this is just a demo program. The application can be
3504 controlled by the following keys:
3505
3506 ? - print current values og the CPM Timer registers
3507 b - enable interrupts and start timer
3508 e - stop timer and disable interrupts
3509 q - quit application
3510
3511 => loads
3512 ## Ready for S-Record download ...
3513 ~>examples/timer.srec
3514 1 2 3 4 5 6 7 8 9 10 11 ...
3515 [file transfer complete]
3516 [connected]
3517 ## Start Addr = 0x00040004
3518
3519 => go 40004
3520 ## Starting application at 0x00040004 ...
3521 TIMERS=0xfff00980
3522 Using timer 1
3523 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3524
3525 Hit 'b':
3526 [q, b, e, ?] Set interval 1000000 us
3527 Enabling timer
3528 Hit '?':
3529 [q, b, e, ?] ........
3530 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3531 Hit '?':
3532 [q, b, e, ?] .
3533 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3534 Hit '?':
3535 [q, b, e, ?] .
3536 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3537 Hit '?':
3538 [q, b, e, ?] .
3539 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3540 Hit 'e':
3541 [q, b, e, ?] ...Stopping timer
3542 Hit 'q':
3543 [q, b, e, ?] ## Application terminated, rc = 0x0
3544
3545
3546 Minicom warning:
3547 ================
3548
3549 Over time, many people have reported problems when trying to use the
3550 "minicom" terminal emulation program for serial download. I (wd)
3551 consider minicom to be broken, and recommend not to use it. Under
3552 Unix, I recommend to use C-Kermit for general purpose use (and
3553 especially for kermit binary protocol download ("loadb" command), and
3554 use "cu" for S-Record download ("loads" command).
3555
3556 Nevertheless, if you absolutely want to use it try adding this
3557 configuration to your "File transfer protocols" section:
3558
3559 Name Program Name U/D FullScr IO-Red. Multi
3560 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3561 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3562
3563
3564 NetBSD Notes:
3565 =============
3566
3567 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3568 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3569
3570 Building requires a cross environment; it is known to work on
3571 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3572 need gmake since the Makefiles are not compatible with BSD make).
3573 Note that the cross-powerpc package does not install include files;
3574 attempting to build U-Boot will fail because <machine/ansi.h> is
3575 missing. This file has to be installed and patched manually:
3576
3577 # cd /usr/pkg/cross/powerpc-netbsd/include
3578 # mkdir powerpc
3579 # ln -s powerpc machine
3580 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3581 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3582
3583 Native builds *don't* work due to incompatibilities between native
3584 and U-Boot include files.
3585
3586 Booting assumes that (the first part of) the image booted is a
3587 stage-2 loader which in turn loads and then invokes the kernel
3588 proper. Loader sources will eventually appear in the NetBSD source
3589 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3590 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3591
3592
3593 Implementation Internals:
3594 =========================
3595
3596 The following is not intended to be a complete description of every
3597 implementation detail. However, it should help to understand the
3598 inner workings of U-Boot and make it easier to port it to custom
3599 hardware.
3600
3601
3602 Initial Stack, Global Data:
3603 ---------------------------
3604
3605 The implementation of U-Boot is complicated by the fact that U-Boot
3606 starts running out of ROM (flash memory), usually without access to
3607 system RAM (because the memory controller is not initialized yet).
3608 This means that we don't have writable Data or BSS segments, and BSS
3609 is not initialized as zero. To be able to get a C environment working
3610 at all, we have to allocate at least a minimal stack. Implementation
3611 options for this are defined and restricted by the CPU used: Some CPU
3612 models provide on-chip memory (like the IMMR area on MPC8xx and
3613 MPC826x processors), on others (parts of) the data cache can be
3614 locked as (mis-) used as memory, etc.
3615
3616 Chris Hallinan posted a good summary of these issues to the
3617 u-boot-users mailing list:
3618
3619 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3620 From: "Chris Hallinan" <clh@net1plus.com>
3621 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3622 ...
3623
3624 Correct me if I'm wrong, folks, but the way I understand it
3625 is this: Using DCACHE as initial RAM for Stack, etc, does not
3626 require any physical RAM backing up the cache. The cleverness
3627 is that the cache is being used as a temporary supply of
3628 necessary storage before the SDRAM controller is setup. It's
3629 beyond the scope of this list to explain the details, but you
3630 can see how this works by studying the cache architecture and
3631 operation in the architecture and processor-specific manuals.
3632
3633 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3634 is another option for the system designer to use as an
3635 initial stack/RAM area prior to SDRAM being available. Either
3636 option should work for you. Using CS 4 should be fine if your
3637 board designers haven't used it for something that would
3638 cause you grief during the initial boot! It is frequently not
3639 used.
3640
3641 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3642 with your processor/board/system design. The default value
3643 you will find in any recent u-boot distribution in
3644 walnut.h should work for you. I'd set it to a value larger
3645 than your SDRAM module. If you have a 64MB SDRAM module, set
3646 it above 400_0000. Just make sure your board has no resources
3647 that are supposed to respond to that address! That code in
3648 start.S has been around a while and should work as is when
3649 you get the config right.
3650
3651 -Chris Hallinan
3652 DS4.COM, Inc.
3653
3654 It is essential to remember this, since it has some impact on the C
3655 code for the initialization procedures:
3656
3657 * Initialized global data (data segment) is read-only. Do not attempt
3658 to write it.
3659
3660 * Do not use any uninitialized global data (or implicitely initialized
3661 as zero data - BSS segment) at all - this is undefined, initiali-
3662 zation is performed later (when relocating to RAM).
3663
3664 * Stack space is very limited. Avoid big data buffers or things like
3665 that.
3666
3667 Having only the stack as writable memory limits means we cannot use
3668 normal global data to share information beween the code. But it
3669 turned out that the implementation of U-Boot can be greatly
3670 simplified by making a global data structure (gd_t) available to all
3671 functions. We could pass a pointer to this data as argument to _all_
3672 functions, but this would bloat the code. Instead we use a feature of
3673 the GCC compiler (Global Register Variables) to share the data: we
3674 place a pointer (gd) to the global data into a register which we
3675 reserve for this purpose.
3676
3677 When choosing a register for such a purpose we are restricted by the
3678 relevant (E)ABI specifications for the current architecture, and by
3679 GCC's implementation.
3680
3681 For PowerPC, the following registers have specific use:
3682 R1: stack pointer
3683 R2: reserved for system use
3684 R3-R4: parameter passing and return values
3685 R5-R10: parameter passing
3686 R13: small data area pointer
3687 R30: GOT pointer
3688 R31: frame pointer
3689
3690 (U-Boot also uses R14 as internal GOT pointer.)
3691
3692 ==> U-Boot will use R2 to hold a pointer to the global data
3693
3694 Note: on PPC, we could use a static initializer (since the
3695 address of the global data structure is known at compile time),
3696 but it turned out that reserving a register results in somewhat
3697 smaller code - although the code savings are not that big (on
3698 average for all boards 752 bytes for the whole U-Boot image,
3699 624 text + 127 data).
3700
3701 On Blackfin, the normal C ABI (except for P5) is followed as documented here:
3702 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
3703
3704 ==> U-Boot will use P5 to hold a pointer to the global data
3705
3706 On ARM, the following registers are used:
3707
3708 R0: function argument word/integer result
3709 R1-R3: function argument word
3710 R9: GOT pointer
3711 R10: stack limit (used only if stack checking if enabled)
3712 R11: argument (frame) pointer
3713 R12: temporary workspace
3714 R13: stack pointer
3715 R14: link register
3716 R15: program counter
3717
3718 ==> U-Boot will use R8 to hold a pointer to the global data
3719
3720 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
3721 or current versions of GCC may "optimize" the code too much.
3722
3723 Memory Management:
3724 ------------------
3725
3726 U-Boot runs in system state and uses physical addresses, i.e. the
3727 MMU is not used either for address mapping nor for memory protection.
3728
3729 The available memory is mapped to fixed addresses using the memory
3730 controller. In this process, a contiguous block is formed for each
3731 memory type (Flash, SDRAM, SRAM), even when it consists of several
3732 physical memory banks.
3733
3734 U-Boot is installed in the first 128 kB of the first Flash bank (on
3735 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3736 booting and sizing and initializing DRAM, the code relocates itself
3737 to the upper end of DRAM. Immediately below the U-Boot code some
3738 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3739 configuration setting]. Below that, a structure with global Board
3740 Info data is placed, followed by the stack (growing downward).
3741
3742 Additionally, some exception handler code is copied to the low 8 kB
3743 of DRAM (0x00000000 ... 0x00001FFF).
3744
3745 So a typical memory configuration with 16 MB of DRAM could look like
3746 this:
3747
3748 0x0000 0000 Exception Vector code
3749 :
3750 0x0000 1FFF
3751 0x0000 2000 Free for Application Use
3752 :
3753 :
3754
3755 :
3756 :
3757 0x00FB FF20 Monitor Stack (Growing downward)
3758 0x00FB FFAC Board Info Data and permanent copy of global data
3759 0x00FC 0000 Malloc Arena
3760 :
3761 0x00FD FFFF
3762 0x00FE 0000 RAM Copy of Monitor Code
3763 ... eventually: LCD or video framebuffer
3764 ... eventually: pRAM (Protected RAM - unchanged by reset)
3765 0x00FF FFFF [End of RAM]
3766
3767
3768 System Initialization:
3769 ----------------------
3770
3771 In the reset configuration, U-Boot starts at the reset entry point
3772 (on most PowerPC systems at address 0x00000100). Because of the reset
3773 configuration for CS0# this is a mirror of the onboard Flash memory.
3774 To be able to re-map memory U-Boot then jumps to its link address.
3775 To be able to implement the initialization code in C, a (small!)
3776 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3777 which provide such a feature like MPC8xx or MPC8260), or in a locked
3778 part of the data cache. After that, U-Boot initializes the CPU core,
3779 the caches and the SIU.
3780
3781 Next, all (potentially) available memory banks are mapped using a
3782 preliminary mapping. For example, we put them on 512 MB boundaries
3783 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3784 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3785 programmed for SDRAM access. Using the temporary configuration, a
3786 simple memory test is run that determines the size of the SDRAM
3787 banks.
3788
3789 When there is more than one SDRAM bank, and the banks are of
3790 different size, the largest is mapped first. For equal size, the first
3791 bank (CS2#) is mapped first. The first mapping is always for address
3792 0x00000000, with any additional banks following immediately to create
3793 contiguous memory starting from 0.
3794
3795 Then, the monitor installs itself at the upper end of the SDRAM area
3796 and allocates memory for use by malloc() and for the global Board
3797 Info data; also, the exception vector code is copied to the low RAM
3798 pages, and the final stack is set up.
3799
3800 Only after this relocation will you have a "normal" C environment;
3801 until that you are restricted in several ways, mostly because you are
3802 running from ROM, and because the code will have to be relocated to a
3803 new address in RAM.
3804
3805
3806 U-Boot Porting Guide:
3807 ----------------------
3808
3809 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3810 list, October 2002]
3811
3812
3813 int main (int argc, char *argv[])
3814 {
3815 sighandler_t no_more_time;
3816
3817 signal (SIGALRM, no_more_time);
3818 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3819
3820 if (available_money > available_manpower) {
3821 pay consultant to port U-Boot;
3822 return 0;
3823 }
3824
3825 Download latest U-Boot source;
3826
3827 Subscribe to u-boot-users mailing list;
3828
3829 if (clueless) {
3830 email ("Hi, I am new to U-Boot, how do I get started?");
3831 }
3832
3833 while (learning) {
3834 Read the README file in the top level directory;
3835 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3836 Read the source, Luke;
3837 }
3838
3839 if (available_money > toLocalCurrency ($2500)) {
3840 Buy a BDI2000;
3841 } else {
3842 Add a lot of aggravation and time;
3843 }
3844
3845 Create your own board support subdirectory;
3846
3847 Create your own board config file;
3848
3849 while (!running) {
3850 do {
3851 Add / modify source code;
3852 } until (compiles);
3853 Debug;
3854 if (clueless)
3855 email ("Hi, I am having problems...");
3856 }
3857 Send patch file to Wolfgang;
3858
3859 return 0;
3860 }
3861
3862 void no_more_time (int sig)
3863 {
3864 hire_a_guru();
3865 }
3866
3867
3868 Coding Standards:
3869 -----------------
3870
3871 All contributions to U-Boot should conform to the Linux kernel
3872 coding style; see the file "Documentation/CodingStyle" and the script
3873 "scripts/Lindent" in your Linux kernel source directory. In sources
3874 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
3875 spaces before parameters to function calls) is actually used.
3876
3877 Source files originating from a different project (for example the
3878 MTD subsystem) are generally exempt from these guidelines and are not
3879 reformated to ease subsequent migration to newer versions of those
3880 sources.
3881
3882 Please note that U-Boot is implemented in C (and to some small parts in
3883 Assembler); no C++ is used, so please do not use C++ style comments (//)
3884 in your code.
3885
3886 Please also stick to the following formatting rules:
3887 - remove any trailing white space
3888 - use TAB characters for indentation, not spaces
3889 - make sure NOT to use DOS '\r\n' line feeds
3890 - do not add more than 2 empty lines to source files
3891 - do not add trailing empty lines to source files
3892
3893 Submissions which do not conform to the standards may be returned
3894 with a request to reformat the changes.
3895
3896
3897 Submitting Patches:
3898 -------------------
3899
3900 Since the number of patches for U-Boot is growing, we need to
3901 establish some rules. Submissions which do not conform to these rules
3902 may be rejected, even when they contain important and valuable stuff.
3903
3904 Patches shall be sent to the u-boot-users mailing list.
3905
3906 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
3907
3908 When you send a patch, please include the following information with
3909 it:
3910
3911 * For bug fixes: a description of the bug and how your patch fixes
3912 this bug. Please try to include a way of demonstrating that the
3913 patch actually fixes something.
3914
3915 * For new features: a description of the feature and your
3916 implementation.
3917
3918 * A CHANGELOG entry as plaintext (separate from the patch)
3919
3920 * For major contributions, your entry to the CREDITS file
3921
3922 * When you add support for a new board, don't forget to add this
3923 board to the MAKEALL script, too.
3924
3925 * If your patch adds new configuration options, don't forget to
3926 document these in the README file.
3927
3928 * The patch itself. If you are using git (which is *strongly*
3929 recommended) you can easily generate the patch using the
3930 "git-format-patch". If you then use "git-send-email" to send it to
3931 the U-Boot mailing list, you will avoid most of the common problems
3932 with some other mail clients.
3933
3934 If you cannot use git, use "diff -purN OLD NEW". If your version of
3935 diff does not support these options, then get the latest version of
3936 GNU diff.
3937
3938 The current directory when running this command shall be the parent
3939 directory of the U-Boot source tree (i. e. please make sure that
3940 your patch includes sufficient directory information for the
3941 affected files).
3942
3943 We prefer patches as plain text. MIME attachments are discouraged,
3944 and compressed attachments must not be used.
3945
3946 * If one logical set of modifications affects or creates several
3947 files, all these changes shall be submitted in a SINGLE patch file.
3948
3949 * Changesets that contain different, unrelated modifications shall be
3950 submitted as SEPARATE patches, one patch per changeset.
3951
3952
3953 Notes:
3954
3955 * Before sending the patch, run the MAKEALL script on your patched
3956 source tree and make sure that no errors or warnings are reported
3957 for any of the boards.
3958
3959 * Keep your modifications to the necessary minimum: A patch
3960 containing several unrelated changes or arbitrary reformats will be
3961 returned with a request to re-formatting / split it.
3962
3963 * If you modify existing code, make sure that your new code does not
3964 add to the memory footprint of the code ;-) Small is beautiful!
3965 When adding new features, these should compile conditionally only
3966 (using #ifdef), and the resulting code with the new feature
3967 disabled must not need more memory than the old code without your
3968 modification.
3969
3970 * Remember that there is a size limit of 40 kB per message on the
3971 u-boot-users mailing list. Bigger patches will be moderated. If
3972 they are reasonable and not bigger than 100 kB, they will be
3973 acknowledged. Even bigger patches should be avoided.