1# 2# (C) Copyright 2000 - 2004 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 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC and ARM processors, which can be 29installed in a boot ROM and used to initialize and test the hardware 30or to download and run application code. 31 32The development of U-Boot is closely related to Linux: some parts of 33the source code originate in the Linux source tree, we have some 34header files in common, and special provision has been made to 35support booting of Linux images. 36 37Some attention has been paid to make this software easily 38configurable and extendable. For instance, all monitor commands are 39implemented with the same call interface, so that it's very easy to 40add new commands. Also, instead of permanently adding rarely used 41code (for instance hardware test utilities) to the monitor, you can 42load and run it dynamically. 43 44 45Status: 46======= 47 48In general, all boards for which a configuration option exists in the 49Makefile have been tested to some extent and can be considered 50"working". In fact, many of them are used in production systems. 51 52In case of problems see the CHANGELOG and CREDITS files to find out 53who contributed the specific port. 54 55 56Where to get help: 57================== 58 59In case you have questions about, problems with or contributions for 60U-Boot you should send a message to the U-Boot mailing list at 61<u-boot-users@lists.sourceforge.net>. There is also an archive of 62previous traffic on the mailing list - please search the archive 63before asking FAQ's. Please see 64http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 65 66 67Where we come from: 68=================== 69 70- start from 8xxrom sources 71- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 72- clean up code 73- make it easier to add custom boards 74- make it possible to add other [PowerPC] CPUs 75- extend functions, especially: 76 * Provide extended interface to Linux boot loader 77 * S-Record download 78 * network boot 79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot 80- create ARMBoot project (http://sourceforge.net/projects/armboot) 81- add other CPU families (starting with ARM) 82- create U-Boot project (http://sourceforge.net/projects/u-boot) 83 84 85Names and Spelling: 86=================== 87 88The "official" name of this project is "Das U-Boot". The spelling 89"U-Boot" shall be used in all written text (documentation, comments 90in source files etc.). Example: 91 92 This is the README file for the U-Boot project. 93 94File names etc. shall be based on the string "u-boot". Examples: 95 96 include/asm-ppc/u-boot.h 97 98 #include <asm/u-boot.h> 99 100Variable names, preprocessor constants etc. shall be either based on 101the string "u_boot" or on "U_BOOT". Example: 102 103 U_BOOT_VERSION u_boot_logo 104 IH_OS_U_BOOT u_boot_hush_start 105 106 107Versioning: 108=========== 109 110U-Boot uses a 3 level version number containing a version, a 111sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 112sub-version "34", and patchlevel "4". 113 114The patchlevel is used to indicate certain stages of development 115between released versions, i. e. officially released versions of 116U-Boot will always have a patchlevel of "0". 117 118 119Directory Hierarchy: 120==================== 121 122- board Board dependent files 123- common Misc architecture independent functions 124- cpu CPU specific files 125 - 74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs 126 - arm720t Files specific to ARM 720 CPUs 127 - arm920t Files specific to ARM 920 CPUs 128 - arm925t Files specific to ARM 925 CPUs 129 - arm926ejs Files specific to ARM 926 CPUs 130 - at91rm9200 Files specific to Atmel AT91RM9200 CPUs 131 - i386 Files specific to i386 CPUs 132 - ixp Files specific to Intel XScale IXP CPUs 133 - mcf52x2 Files specific to Motorola ColdFire MCF52x2 CPUs 134 - mips Files specific to MIPS CPUs 135 - mpc5xx Files specific to Motorola MPC5xx CPUs 136 - mpc5xxx Files specific to Motorola MPC5xxx CPUs 137 - mpc8xx Files specific to Motorola MPC8xx CPUs 138 - mpc824x Files specific to Motorola MPC824x CPUs 139 - mpc8260 Files specific to Motorola MPC8260 CPUs 140 - mpc85xx Files specific to Motorola MPC85xx CPUs 141 - nios Files specific to Altera NIOS CPUs 142 - ppc4xx Files specific to IBM PowerPC 4xx CPUs 143 - pxa Files specific to Intel XScale PXA CPUs 144 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 145 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 146- disk Code for disk drive partition handling 147- doc Documentation (don't expect too much) 148- drivers Commonly used device drivers 149- dtt Digital Thermometer and Thermostat drivers 150- examples Example code for standalone applications, etc. 151- include Header Files 152- lib_arm Files generic to ARM architecture 153- lib_generic Files generic to all architectures 154- lib_i386 Files generic to i386 architecture 155- lib_m68k Files generic to m68k architecture 156- lib_mips Files generic to MIPS architecture 157- lib_nios Files generic to NIOS architecture 158- lib_ppc Files generic to PowerPC architecture 159- net Networking code 160- post Power On Self Test 161- rtc Real Time Clock drivers 162- tools Tools to build S-Record or U-Boot images, etc. 163 164Software Configuration: 165======================= 166 167Configuration is usually done using C preprocessor defines; the 168rationale behind that is to avoid dead code whenever possible. 169 170There are two classes of configuration variables: 171 172* Configuration _OPTIONS_: 173 These are selectable by the user and have names beginning with 174 "CONFIG_". 175 176* Configuration _SETTINGS_: 177 These depend on the hardware etc. and should not be meddled with if 178 you don't know what you're doing; they have names beginning with 179 "CFG_". 180 181Later we will add a configuration tool - probably similar to or even 182identical to what's used for the Linux kernel. Right now, we have to 183do the configuration by hand, which means creating some symbolic 184links and editing some configuration files. We use the TQM8xxL boards 185as an example here. 186 187 188Selection of Processor Architecture and Board Type: 189--------------------------------------------------- 190 191For all supported boards there are ready-to-use default 192configurations available; just type "make <board_name>_config". 193 194Example: For a TQM823L module type: 195 196 cd u-boot 197 make TQM823L_config 198 199For the Cogent platform, you need to specify the cpu type as well; 200e.g. "make cogent_mpc8xx_config". And also configure the cogent 201directory according to the instructions in cogent/README. 202 203 204Configuration Options: 205---------------------- 206 207Configuration depends on the combination of board and CPU type; all 208such information is kept in a configuration file 209"include/configs/<board_name>.h". 210 211Example: For a TQM823L module, all configuration settings are in 212"include/configs/TQM823L.h". 213 214 215Many of the options are named exactly as the corresponding Linux 216kernel configuration options. The intention is to make it easier to 217build a config tool - later. 218 219 220The following options need to be configured: 221 222- CPU Type: Define exactly one of 223 224 PowerPC based CPUs: 225 ------------------- 226 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860 227 or CONFIG_MPC5xx 228 or CONFIG_MPC824X, CONFIG_MPC8260 229 or CONFIG_MPC85xx 230 or CONFIG_IOP480 231 or CONFIG_405GP 232 or CONFIG_405EP 233 or CONFIG_440 234 or CONFIG_MPC74xx 235 or CONFIG_750FX 236 237 ARM based CPUs: 238 --------------- 239 CONFIG_SA1110 240 CONFIG_ARM7 241 CONFIG_PXA250 242 243 244- Board Type: Define exactly one of 245 246 PowerPC based boards: 247 --------------------- 248 249 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper, 250 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850, 251 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS, 252 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T, 253 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240, 254 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245, 255 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L, 256 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L, 257 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L, 258 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L, 259 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260, 260 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech, 261 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245, 262 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC, 263 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG, 264 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405, 265 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA, 266 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon, 267 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260, 268 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx, 269 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260, 270 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260, 271 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes, 272 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod, 273 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon, 274 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e, 275 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260, 276 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto, 277 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260, 278 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L, 279 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI, 280 CONFIG_NETVIA, CONFIG_RBC823, CONFIG_ZPC1900, 281 CONFIG_MPC8540ADS, CONFIG_MPC8560ADS, CONFIG_QS850, 282 CONFIG_QS823, CONFIG_QS860T, CONFIG_DB64360, 283 CONFIG_DB64460, CONFIG_DUET_ADS 284 285 ARM based boards: 286 ----------------- 287 288 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312, 289 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK, 290 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, 291 CONFIG_H2_OMAP1610, CONFIG_SHANNON, CONFIG_SMDK2400, 292 CONFIG_SMDK2410, CONFIG_TRAB, CONFIG_VCMA9, 293 CONFIG_AT91RM9200DK 294 295 296- CPU Module Type: (if CONFIG_COGENT is defined) 297 Define exactly one of 298 CONFIG_CMA286_60_OLD 299--- FIXME --- not tested yet: 300 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 301 CONFIG_CMA287_23, CONFIG_CMA287_50 302 303- Motherboard Type: (if CONFIG_COGENT is defined) 304 Define exactly one of 305 CONFIG_CMA101, CONFIG_CMA102 306 307- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 308 Define one or more of 309 CONFIG_CMA302 310 311- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 312 Define one or more of 313 CONFIG_LCD_HEARTBEAT - update a character position on 314 the lcd display every second with 315 a "rotator" |\-/|\-/ 316 317- Board flavour: (if CONFIG_MPC8260ADS is defined) 318 CONFIG_ADSTYPE 319 Possible values are: 320 CFG_8260ADS - original MPC8260ADS 321 CFG_8266ADS - MPC8266ADS 322 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 323 324 325- MPC824X Family Member (if CONFIG_MPC824X is defined) 326 Define exactly one of 327 CONFIG_MPC8240, CONFIG_MPC8245 328 329- 8xx CPU Options: (if using an MPC8xx cpu) 330 Define one or more of 331 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work 332 e.g. if there is no 32KHz 333 reference PIT/RTC clock 334 335- 859/866 CPU options: (if using a MPC859 or MPC866 CPU): 336 CFG_866_OSCCLK 337 CFG_866_CPUCLK_MIN 338 CFG_866_CPUCLK_MAX 339 CFG_866_CPUCLK_DEFAULT 340 See doc/README.MPC866 341 342 CFG_MEASURE_CPUCLK 343 344 Define this to measure the actual CPU clock instead 345 of relying on the correctness of the configured 346 values. Mostly useful for board bringup to make sure 347 the PLL is locked at the intended frequency. Note 348 that this requires a (stable) reference clock (32 kHz 349 RTC clock), 350 351- Linux Kernel Interface: 352 CONFIG_CLOCKS_IN_MHZ 353 354 U-Boot stores all clock information in Hz 355 internally. For binary compatibility with older Linux 356 kernels (which expect the clocks passed in the 357 bd_info data to be in MHz) the environment variable 358 "clocks_in_mhz" can be defined so that U-Boot 359 converts clock data to MHZ before passing it to the 360 Linux kernel. 361 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 362 "clocks_in_mhz=1" is automatically included in the 363 default environment. 364 365 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 366 367 When transfering memsize parameter to linux, some versions 368 expect it to be in bytes, others in MB. 369 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 370 371- Console Interface: 372 Depending on board, define exactly one serial port 373 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 374 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 375 console by defining CONFIG_8xx_CONS_NONE 376 377 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 378 port routines must be defined elsewhere 379 (i.e. serial_init(), serial_getc(), ...) 380 381 CONFIG_CFB_CONSOLE 382 Enables console device for a color framebuffer. Needs following 383 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 384 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 385 (default big endian) 386 VIDEO_HW_RECTFILL graphic chip supports 387 rectangle fill 388 (cf. smiLynxEM) 389 VIDEO_HW_BITBLT graphic chip supports 390 bit-blit (cf. smiLynxEM) 391 VIDEO_VISIBLE_COLS visible pixel columns 392 (cols=pitch) 393 VIDEO_VISIBLE_ROWS visible pixel rows 394 VIDEO_PIXEL_SIZE bytes per pixel 395 VIDEO_DATA_FORMAT graphic data format 396 (0-5, cf. cfb_console.c) 397 VIDEO_FB_ADRS framebuffer address 398 VIDEO_KBD_INIT_FCT keyboard int fct 399 (i.e. i8042_kbd_init()) 400 VIDEO_TSTC_FCT test char fct 401 (i.e. i8042_tstc) 402 VIDEO_GETC_FCT get char fct 403 (i.e. i8042_getc) 404 CONFIG_CONSOLE_CURSOR cursor drawing on/off 405 (requires blink timer 406 cf. i8042.c) 407 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 408 CONFIG_CONSOLE_TIME display time/date info in 409 upper right corner 410 (requires CFG_CMD_DATE) 411 CONFIG_VIDEO_LOGO display Linux logo in 412 upper left corner 413 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 414 linux_logo.h for logo. 415 Requires CONFIG_VIDEO_LOGO 416 CONFIG_CONSOLE_EXTRA_INFO 417 addional board info beside 418 the logo 419 420 When CONFIG_CFB_CONSOLE is defined, video console is 421 default i/o. Serial console can be forced with 422 environment 'console=serial'. 423 424 When CONFIG_SILENT_CONSOLE is defined, all console 425 messages (by U-Boot and Linux!) can be silenced with 426 the "silent" environment variable. See 427 doc/README.silent for more information. 428 429- Console Baudrate: 430 CONFIG_BAUDRATE - in bps 431 Select one of the baudrates listed in 432 CFG_BAUDRATE_TABLE, see below. 433 CFG_BRGCLK_PRESCALE, baudrate prescale 434 435- Interrupt driven serial port input: 436 CONFIG_SERIAL_SOFTWARE_FIFO 437 438 PPC405GP only. 439 Use an interrupt handler for receiving data on the 440 serial port. It also enables using hardware handshake 441 (RTS/CTS) and UART's built-in FIFO. Set the number of 442 bytes the interrupt driven input buffer should have. 443 444 Set to 0 to disable this feature (this is the default). 445 This will also disable hardware handshake. 446 447- Console UART Number: 448 CONFIG_UART1_CONSOLE 449 450 IBM PPC4xx only. 451 If defined internal UART1 (and not UART0) is used 452 as default U-Boot console. 453 454- Boot Delay: CONFIG_BOOTDELAY - in seconds 455 Delay before automatically booting the default image; 456 set to -1 to disable autoboot. 457 458 See doc/README.autoboot for these options that 459 work with CONFIG_BOOTDELAY. None are required. 460 CONFIG_BOOT_RETRY_TIME 461 CONFIG_BOOT_RETRY_MIN 462 CONFIG_AUTOBOOT_KEYED 463 CONFIG_AUTOBOOT_PROMPT 464 CONFIG_AUTOBOOT_DELAY_STR 465 CONFIG_AUTOBOOT_STOP_STR 466 CONFIG_AUTOBOOT_DELAY_STR2 467 CONFIG_AUTOBOOT_STOP_STR2 468 CONFIG_ZERO_BOOTDELAY_CHECK 469 CONFIG_RESET_TO_RETRY 470 471- Autoboot Command: 472 CONFIG_BOOTCOMMAND 473 Only needed when CONFIG_BOOTDELAY is enabled; 474 define a command string that is automatically executed 475 when no character is read on the console interface 476 within "Boot Delay" after reset. 477 478 CONFIG_BOOTARGS 479 This can be used to pass arguments to the bootm 480 command. The value of CONFIG_BOOTARGS goes into the 481 environment value "bootargs". 482 483 CONFIG_RAMBOOT and CONFIG_NFSBOOT 484 The value of these goes into the environment as 485 "ramboot" and "nfsboot" respectively, and can be used 486 as a convenience, when switching between booting from 487 ram and nfs. 488 489- Pre-Boot Commands: 490 CONFIG_PREBOOT 491 492 When this option is #defined, the existence of the 493 environment variable "preboot" will be checked 494 immediately before starting the CONFIG_BOOTDELAY 495 countdown and/or running the auto-boot command resp. 496 entering interactive mode. 497 498 This feature is especially useful when "preboot" is 499 automatically generated or modified. For an example 500 see the LWMON board specific code: here "preboot" is 501 modified when the user holds down a certain 502 combination of keys on the (special) keyboard when 503 booting the systems 504 505- Serial Download Echo Mode: 506 CONFIG_LOADS_ECHO 507 If defined to 1, all characters received during a 508 serial download (using the "loads" command) are 509 echoed back. This might be needed by some terminal 510 emulations (like "cu"), but may as well just take 511 time on others. This setting #define's the initial 512 value of the "loads_echo" environment variable. 513 514- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined) 515 CONFIG_KGDB_BAUDRATE 516 Select one of the baudrates listed in 517 CFG_BAUDRATE_TABLE, see below. 518 519- Monitor Functions: 520 CONFIG_COMMANDS 521 Most monitor functions can be selected (or 522 de-selected) by adjusting the definition of 523 CONFIG_COMMANDS; to select individual functions, 524 #define CONFIG_COMMANDS by "OR"ing any of the 525 following values: 526 527 #define enables commands: 528 ------------------------- 529 CFG_CMD_ASKENV * ask for env variable 530 CFG_CMD_AUTOSCRIPT Autoscript Support 531 CFG_CMD_BDI bdinfo 532 CFG_CMD_BEDBUG Include BedBug Debugger 533 CFG_CMD_BMP * BMP support 534 CFG_CMD_BOOTD bootd 535 CFG_CMD_CACHE icache, dcache 536 CFG_CMD_CONSOLE coninfo 537 CFG_CMD_DATE * support for RTC, date/time... 538 CFG_CMD_DHCP DHCP support 539 CFG_CMD_DIAG * Diagnostics 540 CFG_CMD_DOC * Disk-On-Chip Support 541 CFG_CMD_DTT Digital Therm and Thermostat 542 CFG_CMD_ECHO * echo arguments 543 CFG_CMD_EEPROM * EEPROM read/write support 544 CFG_CMD_ELF bootelf, bootvx 545 CFG_CMD_ENV saveenv 546 CFG_CMD_FDC * Floppy Disk Support 547 CFG_CMD_FAT FAT partition support 548 CFG_CMD_FDOS * Dos diskette Support 549 CFG_CMD_FLASH flinfo, erase, protect 550 CFG_CMD_FPGA FPGA device initialization support 551 CFG_CMD_HWFLOW * RTS/CTS hw flow control 552 CFG_CMD_I2C * I2C serial bus support 553 CFG_CMD_IDE * IDE harddisk support 554 CFG_CMD_IMI iminfo 555 CFG_CMD_IMLS List all found images 556 CFG_CMD_IMMAP * IMMR dump support 557 CFG_CMD_IRQ * irqinfo 558 CFG_CMD_ITEST * Integer/string test of 2 values 559 CFG_CMD_JFFS2 * JFFS2 Support 560 CFG_CMD_KGDB * kgdb 561 CFG_CMD_LOADB loadb 562 CFG_CMD_LOADS loads 563 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 564 loop, mtest 565 CFG_CMD_MISC Misc functions like sleep etc 566 CFG_CMD_MMC MMC memory mapped support 567 CFG_CMD_MII MII utility commands 568 CFG_CMD_NAND * NAND support 569 CFG_CMD_NET bootp, tftpboot, rarpboot 570 CFG_CMD_PCI * pciinfo 571 CFG_CMD_PCMCIA * PCMCIA support 572 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host 573 CFG_CMD_PORTIO * Port I/O 574 CFG_CMD_REGINFO * Register dump 575 CFG_CMD_RUN run command in env variable 576 CFG_CMD_SAVES save S record dump 577 CFG_CMD_SCSI * SCSI Support 578 CFG_CMD_SDRAM * print SDRAM configuration information 579 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only) 580 CFG_CMD_SPI * SPI serial bus support 581 CFG_CMD_USB * USB support 582 CFG_CMD_VFD * VFD support (TRAB) 583 CFG_CMD_BSP * Board SPecific functions 584 ----------------------------------------------- 585 CFG_CMD_ALL all 586 587 CFG_CMD_DFL Default configuration; at the moment 588 this is includes all commands, except 589 the ones marked with "*" in the list 590 above. 591 592 If you don't define CONFIG_COMMANDS it defaults to 593 CFG_CMD_DFL in include/cmd_confdefs.h. A board can 594 override the default settings in the respective 595 include file. 596 597 EXAMPLE: If you want all functions except of network 598 support you can write: 599 600 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET) 601 602 603 Note: Don't enable the "icache" and "dcache" commands 604 (configuration option CFG_CMD_CACHE) unless you know 605 what you (and your U-Boot users) are doing. Data 606 cache cannot be enabled on systems like the 8xx or 607 8260 (where accesses to the IMMR region must be 608 uncached), and it cannot be disabled on all other 609 systems where we (mis-) use the data cache to hold an 610 initial stack and some data. 611 612 613 XXX - this list needs to get updated! 614 615- Watchdog: 616 CONFIG_WATCHDOG 617 If this variable is defined, it enables watchdog 618 support. There must be support in the platform specific 619 code for a watchdog. For the 8xx and 8260 CPUs, the 620 SIU Watchdog feature is enabled in the SYPCR 621 register. 622 623- U-Boot Version: 624 CONFIG_VERSION_VARIABLE 625 If this variable is defined, an environment variable 626 named "ver" is created by U-Boot showing the U-Boot 627 version as printed by the "version" command. 628 This variable is readonly. 629 630- Real-Time Clock: 631 632 When CFG_CMD_DATE is selected, the type of the RTC 633 has to be selected, too. Define exactly one of the 634 following options: 635 636 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 637 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 638 CONFIG_RTC_MC146818 - use MC146818 RTC 639 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 640 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 641 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 642 CONFIG_RTC_DS164x - use Dallas DS164x RTC 643 644 Note that if the RTC uses I2C, then the I2C interface 645 must also be configured. See I2C Support, below. 646 647- Timestamp Support: 648 649 When CONFIG_TIMESTAMP is selected, the timestamp 650 (date and time) of an image is printed by image 651 commands like bootm or iminfo. This option is 652 automatically enabled when you select CFG_CMD_DATE . 653 654- Partition Support: 655 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 656 and/or CONFIG_ISO_PARTITION 657 658 If IDE or SCSI support is enabled (CFG_CMD_IDE or 659 CFG_CMD_SCSI) you must configure support for at least 660 one partition type as well. 661 662- IDE Reset method: 663 CONFIG_IDE_RESET_ROUTINE 664 665 Set this to define that instead of a reset Pin, the 666 routine ide_set_reset(int idereset) will be used. 667 668- ATAPI Support: 669 CONFIG_ATAPI 670 671 Set this to enable ATAPI support. 672 673- SCSI Support: 674 At the moment only there is only support for the 675 SYM53C8XX SCSI controller; define 676 CONFIG_SCSI_SYM53C8XX to enable it. 677 678 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 679 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 680 CFG_SCSI_MAX_LUN] can be adjusted to define the 681 maximum numbers of LUNs, SCSI ID's and target 682 devices. 683 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 684 685- NETWORK Support (PCI): 686 CONFIG_E1000 687 Support for Intel 8254x gigabit chips. 688 689 CONFIG_EEPRO100 690 Support for Intel 82557/82559/82559ER chips. 691 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 692 write routine for first time initialisation. 693 694 CONFIG_TULIP 695 Support for Digital 2114x chips. 696 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 697 modem chip initialisation (KS8761/QS6611). 698 699 CONFIG_NATSEMI 700 Support for National dp83815 chips. 701 702 CONFIG_NS8382X 703 Support for National dp8382[01] gigabit chips. 704 705- NETWORK Support (other): 706 707 CONFIG_DRIVER_LAN91C96 708 Support for SMSC's LAN91C96 chips. 709 710 CONFIG_LAN91C96_BASE 711 Define this to hold the physical address 712 of the LAN91C96's I/O space 713 714 CONFIG_LAN91C96_USE_32_BIT 715 Define this to enable 32 bit addressing 716 717- USB Support: 718 At the moment only the UHCI host controller is 719 supported (PIP405, MIP405); define 720 CONFIG_USB_UHCI to enable it. 721 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 722 end define CONFIG_USB_STORAGE to enable the USB 723 storage devices. 724 Note: 725 Supported are USB Keyboards and USB Floppy drives 726 (TEAC FD-05PUB). 727 728- MMC Support: 729 The MMC controller on the Intel PXA is supported. To 730 enable this define CONFIG_MMC. The MMC can be 731 accessed from the boot prompt by mapping the device 732 to physical memory similar to flash. Command line is 733 enabled with CFG_CMD_MMC. The MMC driver also works with 734 the FAT fs. This is enabled with CFG_CMD_FAT. 735 736- Keyboard Support: 737 CONFIG_ISA_KEYBOARD 738 739 Define this to enable standard (PC-Style) keyboard 740 support 741 742 CONFIG_I8042_KBD 743 Standard PC keyboard driver with US (is default) and 744 GERMAN key layout (switch via environment 'keymap=de') support. 745 Export function i8042_kbd_init, i8042_tstc and i8042_getc 746 for cfb_console. Supports cursor blinking. 747 748- Video support: 749 CONFIG_VIDEO 750 751 Define this to enable video support (for output to 752 video). 753 754 CONFIG_VIDEO_CT69000 755 756 Enable Chips & Technologies 69000 Video chip 757 758 CONFIG_VIDEO_SMI_LYNXEM 759 Enable Silicon Motion SMI 712/710/810 Video chip 760 Videomode are selected via environment 'videomode' with 761 standard LiLo mode numbers. 762 Following modes are supported (* is default): 763 764 800x600 1024x768 1280x1024 765 256 (8bit) 303* 305 307 766 65536 (16bit) 314 317 31a 767 16,7 Mill (24bit) 315 318 31b 768 (i.e. setenv videomode 317; saveenv; reset;) 769 770 CONFIG_VIDEO_SED13806 771 Enable Epson SED13806 driver. This driver supports 8bpp 772 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 773 or CONFIG_VIDEO_SED13806_16BPP 774 775- Keyboard Support: 776 CONFIG_KEYBOARD 777 778 Define this to enable a custom keyboard support. 779 This simply calls drv_keyboard_init() which must be 780 defined in your board-specific files. 781 The only board using this so far is RBC823. 782 783- LCD Support: CONFIG_LCD 784 785 Define this to enable LCD support (for output to LCD 786 display); also select one of the supported displays 787 by defining one of these: 788 789 CONFIG_NEC_NL6448AC33: 790 791 NEC NL6448AC33-18. Active, color, single scan. 792 793 CONFIG_NEC_NL6448BC20 794 795 NEC NL6448BC20-08. 6.5", 640x480. 796 Active, color, single scan. 797 798 CONFIG_NEC_NL6448BC33_54 799 800 NEC NL6448BC33-54. 10.4", 640x480. 801 Active, color, single scan. 802 803 CONFIG_SHARP_16x9 804 805 Sharp 320x240. Active, color, single scan. 806 It isn't 16x9, and I am not sure what it is. 807 808 CONFIG_SHARP_LQ64D341 809 810 Sharp LQ64D341 display, 640x480. 811 Active, color, single scan. 812 813 CONFIG_HLD1045 814 815 HLD1045 display, 640x480. 816 Active, color, single scan. 817 818 CONFIG_OPTREX_BW 819 820 Optrex CBL50840-2 NF-FW 99 22 M5 821 or 822 Hitachi LMG6912RPFC-00T 823 or 824 Hitachi SP14Q002 825 826 320x240. Black & white. 827 828 Normally display is black on white background; define 829 CFG_WHITE_ON_BLACK to get it inverted. 830 831- Splash Screen Support: CONFIG_SPLASH_SCREEN 832 833 If this option is set, the environment is checked for 834 a variable "splashimage". If found, the usual display 835 of logo, copyright and system information on the LCD 836 is supressed and the BMP image at the address 837 specified in "splashimage" is loaded instead. The 838 console is redirected to the "nulldev", too. This 839 allows for a "silent" boot where a splash screen is 840 loaded very quickly after power-on. 841 842- Compression support: 843 CONFIG_BZIP2 844 845 If this option is set, support for bzip2 compressed 846 images is included. If not, only uncompressed and gzip 847 compressed images are supported. 848 849 NOTE: the bzip2 algorithm requires a lot of RAM, so 850 the malloc area (as defined by CFG_MALLOC_LEN) should 851 be at least 4MB. 852 853- Ethernet address: 854 CONFIG_ETHADDR 855 CONFIG_ETH2ADDR 856 CONFIG_ETH3ADDR 857 858 Define a default value for ethernet address to use 859 for the respective ethernet interface, in case this 860 is not determined automatically. 861 862- IP address: 863 CONFIG_IPADDR 864 865 Define a default value for the IP address to use for 866 the default ethernet interface, in case this is not 867 determined through e.g. bootp. 868 869- Server IP address: 870 CONFIG_SERVERIP 871 872 Defines a default value for theIP address of a TFTP 873 server to contact when using the "tftboot" command. 874 875- BOOTP Recovery Mode: 876 CONFIG_BOOTP_RANDOM_DELAY 877 878 If you have many targets in a network that try to 879 boot using BOOTP, you may want to avoid that all 880 systems send out BOOTP requests at precisely the same 881 moment (which would happen for instance at recovery 882 from a power failure, when all systems will try to 883 boot, thus flooding the BOOTP server. Defining 884 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 885 inserted before sending out BOOTP requests. The 886 following delays are insterted then: 887 888 1st BOOTP request: delay 0 ... 1 sec 889 2nd BOOTP request: delay 0 ... 2 sec 890 3rd BOOTP request: delay 0 ... 4 sec 891 4th and following 892 BOOTP requests: delay 0 ... 8 sec 893 894- DHCP Advanced Options: 895 CONFIG_BOOTP_MASK 896 897 You can fine tune the DHCP functionality by adding 898 these flags to the CONFIG_BOOTP_MASK define: 899 900 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 901 serverip from a DHCP server, it is possible that more 902 than one DNS serverip is offered to the client. 903 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 904 serverip will be stored in the additional environment 905 variable "dnsip2". The first DNS serverip is always 906 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 907 is added to the CONFIG_BOOTP_MASK. 908 909 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 910 to do a dynamic update of a DNS server. To do this, they 911 need the hostname of the DHCP requester. 912 If CONFIG_BOOP_SEND_HOSTNAME is added to the 913 CONFIG_BOOTP_MASK, the content of the "hostname" 914 environment variable is passed as option 12 to 915 the DHCP server. 916 917- Status LED: CONFIG_STATUS_LED 918 919 Several configurations allow to display the current 920 status using a LED. For instance, the LED will blink 921 fast while running U-Boot code, stop blinking as 922 soon as a reply to a BOOTP request was received, and 923 start blinking slow once the Linux kernel is running 924 (supported by a status LED driver in the Linux 925 kernel). Defining CONFIG_STATUS_LED enables this 926 feature in U-Boot. 927 928- CAN Support: CONFIG_CAN_DRIVER 929 930 Defining CONFIG_CAN_DRIVER enables CAN driver support 931 on those systems that support this (optional) 932 feature, like the TQM8xxL modules. 933 934- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 935 936 These enable I2C serial bus commands. Defining either of 937 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 938 include the appropriate I2C driver for the selected cpu. 939 940 This will allow you to use i2c commands at the u-boot 941 command line (as long as you set CFG_CMD_I2C in 942 CONFIG_COMMANDS) and communicate with i2c based realtime 943 clock chips. See common/cmd_i2c.c for a description of the 944 command line interface. 945 946 CONFIG_HARD_I2C selects the CPM hardware driver for I2C. 947 948 CONFIG_SOFT_I2C configures u-boot to use a software (aka 949 bit-banging) driver instead of CPM or similar hardware 950 support for I2C. 951 952 There are several other quantities that must also be 953 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 954 955 In both cases you will need to define CFG_I2C_SPEED 956 to be the frequency (in Hz) at which you wish your i2c bus 957 to run and CFG_I2C_SLAVE to be the address of this node (ie 958 the cpu's i2c node address). 959 960 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 961 sets the cpu up as a master node and so its address should 962 therefore be cleared to 0 (See, eg, MPC823e User's Manual 963 p.16-473). So, set CFG_I2C_SLAVE to 0. 964 965 That's all that's required for CONFIG_HARD_I2C. 966 967 If you use the software i2c interface (CONFIG_SOFT_I2C) 968 then the following macros need to be defined (examples are 969 from include/configs/lwmon.h): 970 971 I2C_INIT 972 973 (Optional). Any commands necessary to enable the I2C 974 controller or configure ports. 975 976 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 977 978 I2C_PORT 979 980 (Only for MPC8260 CPU). The I/O port to use (the code 981 assumes both bits are on the same port). Valid values 982 are 0..3 for ports A..D. 983 984 I2C_ACTIVE 985 986 The code necessary to make the I2C data line active 987 (driven). If the data line is open collector, this 988 define can be null. 989 990 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 991 992 I2C_TRISTATE 993 994 The code necessary to make the I2C data line tri-stated 995 (inactive). If the data line is open collector, this 996 define can be null. 997 998 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 999 1000 I2C_READ 1001 1002 Code that returns TRUE if the I2C data line is high, 1003 FALSE if it is low. 1004 1005 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1006 1007 I2C_SDA(bit) 1008 1009 If <bit> is TRUE, sets the I2C data line high. If it 1010 is FALSE, it clears it (low). 1011 1012 eg: #define I2C_SDA(bit) \ 1013 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1014 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1015 1016 I2C_SCL(bit) 1017 1018 If <bit> is TRUE, sets the I2C clock line high. If it 1019 is FALSE, it clears it (low). 1020 1021 eg: #define I2C_SCL(bit) \ 1022 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1023 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1024 1025 I2C_DELAY 1026 1027 This delay is invoked four times per clock cycle so this 1028 controls the rate of data transfer. The data rate thus 1029 is 1 / (I2C_DELAY * 4). Often defined to be something 1030 like: 1031 1032 #define I2C_DELAY udelay(2) 1033 1034 CFG_I2C_INIT_BOARD 1035 1036 When a board is reset during an i2c bus transfer 1037 chips might think that the current transfer is still 1038 in progress. On some boards it is possible to access 1039 the i2c SCLK line directly, either by using the 1040 processor pin as a GPIO or by having a second pin 1041 connected to the bus. If this option is defined a 1042 custom i2c_init_board() routine in boards/xxx/board.c 1043 is run early in the boot sequence. 1044 1045- SPI Support: CONFIG_SPI 1046 1047 Enables SPI driver (so far only tested with 1048 SPI EEPROM, also an instance works with Crystal A/D and 1049 D/As on the SACSng board) 1050 1051 CONFIG_SPI_X 1052 1053 Enables extended (16-bit) SPI EEPROM addressing. 1054 (symmetrical to CONFIG_I2C_X) 1055 1056 CONFIG_SOFT_SPI 1057 1058 Enables a software (bit-bang) SPI driver rather than 1059 using hardware support. This is a general purpose 1060 driver that only requires three general I/O port pins 1061 (two outputs, one input) to function. If this is 1062 defined, the board configuration must define several 1063 SPI configuration items (port pins to use, etc). For 1064 an example, see include/configs/sacsng.h. 1065 1066- FPGA Support: CONFIG_FPGA_COUNT 1067 1068 Specify the number of FPGA devices to support. 1069 1070 CONFIG_FPGA 1071 1072 Used to specify the types of FPGA devices. For example, 1073 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1074 1075 CFG_FPGA_PROG_FEEDBACK 1076 1077 Enable printing of hash marks during FPGA configuration. 1078 1079 CFG_FPGA_CHECK_BUSY 1080 1081 Enable checks on FPGA configuration interface busy 1082 status by the configuration function. This option 1083 will require a board or device specific function to 1084 be written. 1085 1086 CONFIG_FPGA_DELAY 1087 1088 If defined, a function that provides delays in the FPGA 1089 configuration driver. 1090 1091 CFG_FPGA_CHECK_CTRLC 1092 Allow Control-C to interrupt FPGA configuration 1093 1094 CFG_FPGA_CHECK_ERROR 1095 1096 Check for configuration errors during FPGA bitfile 1097 loading. For example, abort during Virtex II 1098 configuration if the INIT_B line goes low (which 1099 indicated a CRC error). 1100 1101 CFG_FPGA_WAIT_INIT 1102 1103 Maximum time to wait for the INIT_B line to deassert 1104 after PROB_B has been deasserted during a Virtex II 1105 FPGA configuration sequence. The default time is 500 1106 mS. 1107 1108 CFG_FPGA_WAIT_BUSY 1109 1110 Maximum time to wait for BUSY to deassert during 1111 Virtex II FPGA configuration. The default is 5 mS. 1112 1113 CFG_FPGA_WAIT_CONFIG 1114 1115 Time to wait after FPGA configuration. The default is 1116 200 mS. 1117 1118- Configuration Management: 1119 CONFIG_IDENT_STRING 1120 1121 If defined, this string will be added to the U-Boot 1122 version information (U_BOOT_VERSION) 1123 1124- Vendor Parameter Protection: 1125 1126 U-Boot considers the values of the environment 1127 variables "serial#" (Board Serial Number) and 1128 "ethaddr" (Ethernet Address) to be parameters that 1129 are set once by the board vendor / manufacturer, and 1130 protects these variables from casual modification by 1131 the user. Once set, these variables are read-only, 1132 and write or delete attempts are rejected. You can 1133 change this behviour: 1134 1135 If CONFIG_ENV_OVERWRITE is #defined in your config 1136 file, the write protection for vendor parameters is 1137 completely disabled. Anybody can change or delete 1138 these parameters. 1139 1140 Alternatively, if you #define _both_ CONFIG_ETHADDR 1141 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1142 ethernet address is installed in the environment, 1143 which can be changed exactly ONCE by the user. [The 1144 serial# is unaffected by this, i. e. it remains 1145 read-only.] 1146 1147- Protected RAM: 1148 CONFIG_PRAM 1149 1150 Define this variable to enable the reservation of 1151 "protected RAM", i. e. RAM which is not overwritten 1152 by U-Boot. Define CONFIG_PRAM to hold the number of 1153 kB you want to reserve for pRAM. You can overwrite 1154 this default value by defining an environment 1155 variable "pram" to the number of kB you want to 1156 reserve. Note that the board info structure will 1157 still show the full amount of RAM. If pRAM is 1158 reserved, a new environment variable "mem" will 1159 automatically be defined to hold the amount of 1160 remaining RAM in a form that can be passed as boot 1161 argument to Linux, for instance like that: 1162 1163 setenv bootargs ... mem=\$(mem) 1164 saveenv 1165 1166 This way you can tell Linux not to use this memory, 1167 either, which results in a memory region that will 1168 not be affected by reboots. 1169 1170 *WARNING* If your board configuration uses automatic 1171 detection of the RAM size, you must make sure that 1172 this memory test is non-destructive. So far, the 1173 following board configurations are known to be 1174 "pRAM-clean": 1175 1176 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1177 HERMES, IP860, RPXlite, LWMON, LANTEC, 1178 PCU_E, FLAGADM, TQM8260 1179 1180- Error Recovery: 1181 CONFIG_PANIC_HANG 1182 1183 Define this variable to stop the system in case of a 1184 fatal error, so that you have to reset it manually. 1185 This is probably NOT a good idea for an embedded 1186 system where you want to system to reboot 1187 automatically as fast as possible, but it may be 1188 useful during development since you can try to debug 1189 the conditions that lead to the situation. 1190 1191 CONFIG_NET_RETRY_COUNT 1192 1193 This variable defines the number of retries for 1194 network operations like ARP, RARP, TFTP, or BOOTP 1195 before giving up the operation. If not defined, a 1196 default value of 5 is used. 1197 1198- Command Interpreter: 1199 CFG_HUSH_PARSER 1200 1201 Define this variable to enable the "hush" shell (from 1202 Busybox) as command line interpreter, thus enabling 1203 powerful command line syntax like 1204 if...then...else...fi conditionals or `&&' and '||' 1205 constructs ("shell scripts"). 1206 1207 If undefined, you get the old, much simpler behaviour 1208 with a somewhat smaller memory footprint. 1209 1210 1211 CFG_PROMPT_HUSH_PS2 1212 1213 This defines the secondary prompt string, which is 1214 printed when the command interpreter needs more input 1215 to complete a command. Usually "> ". 1216 1217 Note: 1218 1219 In the current implementation, the local variables 1220 space and global environment variables space are 1221 separated. Local variables are those you define by 1222 simply typing `name=value'. To access a local 1223 variable later on, you have write `$name' or 1224 `${name}'; to execute the contents of a variable 1225 directly type `$name' at the command prompt. 1226 1227 Global environment variables are those you use 1228 setenv/printenv to work with. To run a command stored 1229 in such a variable, you need to use the run command, 1230 and you must not use the '$' sign to access them. 1231 1232 To store commands and special characters in a 1233 variable, please use double quotation marks 1234 surrounding the whole text of the variable, instead 1235 of the backslashes before semicolons and special 1236 symbols. 1237 1238- Default Environment: 1239 CONFIG_EXTRA_ENV_SETTINGS 1240 1241 Define this to contain any number of null terminated 1242 strings (variable = value pairs) that will be part of 1243 the default environment compiled into the boot image. 1244 1245 For example, place something like this in your 1246 board's config file: 1247 1248 #define CONFIG_EXTRA_ENV_SETTINGS \ 1249 "myvar1=value1\0" \ 1250 "myvar2=value2\0" 1251 1252 Warning: This method is based on knowledge about the 1253 internal format how the environment is stored by the 1254 U-Boot code. This is NOT an official, exported 1255 interface! Although it is unlikely that this format 1256 will change soon, there is no guarantee either. 1257 You better know what you are doing here. 1258 1259 Note: overly (ab)use of the default environment is 1260 discouraged. Make sure to check other ways to preset 1261 the environment like the autoscript function or the 1262 boot command first. 1263 1264- DataFlash Support: 1265 CONFIG_HAS_DATAFLASH 1266 1267 Defining this option enables DataFlash features and 1268 allows to read/write in Dataflash via the standard 1269 commands cp, md... 1270 1271- SystemACE Support: 1272 CONFIG_SYSTEMACE 1273 1274 Adding this option adds support for Xilinx SystemACE 1275 chips attached via some sort of local bus. The address 1276 of the chip must alsh be defined in the 1277 CFG_SYSTEMACE_BASE macro. For example: 1278 1279 #define CONFIG_SYSTEMACE 1280 #define CFG_SYSTEMACE_BASE 0xf0000000 1281 1282 When SystemACE support is added, the "ace" device type 1283 becomes available to the fat commands, i.e. fatls. 1284 1285- Show boot progress: 1286 CONFIG_SHOW_BOOT_PROGRESS 1287 1288 Defining this option allows to add some board- 1289 specific code (calling a user-provided function 1290 "show_boot_progress(int)") that enables you to show 1291 the system's boot progress on some display (for 1292 example, some LED's) on your board. At the moment, 1293 the following checkpoints are implemented: 1294 1295 Arg Where When 1296 1 common/cmd_bootm.c before attempting to boot an image 1297 -1 common/cmd_bootm.c Image header has bad magic number 1298 2 common/cmd_bootm.c Image header has correct magic number 1299 -2 common/cmd_bootm.c Image header has bad checksum 1300 3 common/cmd_bootm.c Image header has correct checksum 1301 -3 common/cmd_bootm.c Image data has bad checksum 1302 4 common/cmd_bootm.c Image data has correct checksum 1303 -4 common/cmd_bootm.c Image is for unsupported architecture 1304 5 common/cmd_bootm.c Architecture check OK 1305 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1306 6 common/cmd_bootm.c Image Type check OK 1307 -6 common/cmd_bootm.c gunzip uncompression error 1308 -7 common/cmd_bootm.c Unimplemented compression type 1309 7 common/cmd_bootm.c Uncompression OK 1310 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1311 8 common/cmd_bootm.c Image Type check OK 1312 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1313 9 common/cmd_bootm.c Start initial ramdisk verification 1314 -10 common/cmd_bootm.c Ramdisk header has bad magic number 1315 -11 common/cmd_bootm.c Ramdisk header has bad checksum 1316 10 common/cmd_bootm.c Ramdisk header is OK 1317 -12 common/cmd_bootm.c Ramdisk data has bad checksum 1318 11 common/cmd_bootm.c Ramdisk data has correct checksum 1319 12 common/cmd_bootm.c Ramdisk verification complete, start loading 1320 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk) 1321 13 common/cmd_bootm.c Start multifile image verification 1322 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue. 1323 15 common/cmd_bootm.c All preparation done, transferring control to OS 1324 1325 -30 lib_ppc/board.c Fatal error, hang the system 1326 -31 post/post.c POST test failed, detected by post_output_backlog() 1327 -32 post/post.c POST test failed, detected by post_run_single() 1328 1329 -1 common/cmd_doc.c Bad usage of "doc" command 1330 -1 common/cmd_doc.c No boot device 1331 -1 common/cmd_doc.c Unknown Chip ID on boot device 1332 -1 common/cmd_doc.c Read Error on boot device 1333 -1 common/cmd_doc.c Image header has bad magic number 1334 1335 -1 common/cmd_ide.c Bad usage of "ide" command 1336 -1 common/cmd_ide.c No boot device 1337 -1 common/cmd_ide.c Unknown boot device 1338 -1 common/cmd_ide.c Unknown partition table 1339 -1 common/cmd_ide.c Invalid partition type 1340 -1 common/cmd_ide.c Read Error on boot device 1341 -1 common/cmd_ide.c Image header has bad magic number 1342 1343 -1 common/cmd_nand.c Bad usage of "nand" command 1344 -1 common/cmd_nand.c No boot device 1345 -1 common/cmd_nand.c Unknown Chip ID on boot device 1346 -1 common/cmd_nand.c Read Error on boot device 1347 -1 common/cmd_nand.c Image header has bad magic number 1348 1349 -1 common/env_common.c Environment has a bad CRC, using default 1350 1351 1352Modem Support: 1353-------------- 1354 1355[so far only for SMDK2400 and TRAB boards] 1356 1357- Modem support endable: 1358 CONFIG_MODEM_SUPPORT 1359 1360- RTS/CTS Flow control enable: 1361 CONFIG_HWFLOW 1362 1363- Modem debug support: 1364 CONFIG_MODEM_SUPPORT_DEBUG 1365 1366 Enables debugging stuff (char screen[1024], dbg()) 1367 for modem support. Useful only with BDI2000. 1368 1369- Interrupt support (PPC): 1370 1371 There are common interrupt_init() and timer_interrupt() 1372 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1373 for cpu specific initialization. interrupt_init_cpu() 1374 should set decrementer_count to appropriate value. If 1375 cpu resets decrementer automatically after interrupt 1376 (ppc4xx) it should set decrementer_count to zero. 1377 timer_interrupt() calls timer_interrupt_cpu() for cpu 1378 specific handling. If board has watchdog / status_led 1379 / other_activity_monitor it works automatically from 1380 general timer_interrupt(). 1381 1382- General: 1383 1384 In the target system modem support is enabled when a 1385 specific key (key combination) is pressed during 1386 power-on. Otherwise U-Boot will boot normally 1387 (autoboot). The key_pressed() fuction is called from 1388 board_init(). Currently key_pressed() is a dummy 1389 function, returning 1 and thus enabling modem 1390 initialization. 1391 1392 If there are no modem init strings in the 1393 environment, U-Boot proceed to autoboot; the 1394 previous output (banner, info printfs) will be 1395 supressed, though. 1396 1397 See also: doc/README.Modem 1398 1399 1400Configuration Settings: 1401----------------------- 1402 1403- CFG_LONGHELP: Defined when you want long help messages included; 1404 undefine this when you're short of memory. 1405 1406- CFG_PROMPT: This is what U-Boot prints on the console to 1407 prompt for user input. 1408 1409- CFG_CBSIZE: Buffer size for input from the Console 1410 1411- CFG_PBSIZE: Buffer size for Console output 1412 1413- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1414 1415- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1416 the application (usually a Linux kernel) when it is 1417 booted 1418 1419- CFG_BAUDRATE_TABLE: 1420 List of legal baudrate settings for this board. 1421 1422- CFG_CONSOLE_INFO_QUIET 1423 Suppress display of console information at boot. 1424 1425- CFG_CONSOLE_IS_IN_ENV 1426 If the board specific function 1427 extern int overwrite_console (void); 1428 returns 1, the stdin, stderr and stdout are switched to the 1429 serial port, else the settings in the environment are used. 1430 1431- CFG_CONSOLE_OVERWRITE_ROUTINE 1432 Enable the call to overwrite_console(). 1433 1434- CFG_CONSOLE_ENV_OVERWRITE 1435 Enable overwrite of previous console environment settings. 1436 1437- CFG_MEMTEST_START, CFG_MEMTEST_END: 1438 Begin and End addresses of the area used by the 1439 simple memory test. 1440 1441- CFG_ALT_MEMTEST: 1442 Enable an alternate, more extensive memory test. 1443 1444- CFG_MEMTEST_SCRATCH: 1445 Scratch address used by the alternate memory test 1446 You only need to set this if address zero isn't writeable 1447 1448- CFG_TFTP_LOADADDR: 1449 Default load address for network file downloads 1450 1451- CFG_LOADS_BAUD_CHANGE: 1452 Enable temporary baudrate change while serial download 1453 1454- CFG_SDRAM_BASE: 1455 Physical start address of SDRAM. _Must_ be 0 here. 1456 1457- CFG_MBIO_BASE: 1458 Physical start address of Motherboard I/O (if using a 1459 Cogent motherboard) 1460 1461- CFG_FLASH_BASE: 1462 Physical start address of Flash memory. 1463 1464- CFG_MONITOR_BASE: 1465 Physical start address of boot monitor code (set by 1466 make config files to be same as the text base address 1467 (TEXT_BASE) used when linking) - same as 1468 CFG_FLASH_BASE when booting from flash. 1469 1470- CFG_MONITOR_LEN: 1471 Size of memory reserved for monitor code, used to 1472 determine _at_compile_time_ (!) if the environment is 1473 embedded within the U-Boot image, or in a separate 1474 flash sector. 1475 1476- CFG_MALLOC_LEN: 1477 Size of DRAM reserved for malloc() use. 1478 1479- CFG_BOOTMAPSZ: 1480 Maximum size of memory mapped by the startup code of 1481 the Linux kernel; all data that must be processed by 1482 the Linux kernel (bd_info, boot arguments, eventually 1483 initrd image) must be put below this limit. 1484 1485- CFG_MAX_FLASH_BANKS: 1486 Max number of Flash memory banks 1487 1488- CFG_MAX_FLASH_SECT: 1489 Max number of sectors on a Flash chip 1490 1491- CFG_FLASH_ERASE_TOUT: 1492 Timeout for Flash erase operations (in ms) 1493 1494- CFG_FLASH_WRITE_TOUT: 1495 Timeout for Flash write operations (in ms) 1496 1497- CFG_FLASH_LOCK_TOUT 1498 Timeout for Flash set sector lock bit operation (in ms) 1499 1500- CFG_FLASH_UNLOCK_TOUT 1501 Timeout for Flash clear lock bits operation (in ms) 1502 1503- CFG_FLASH_PROTECTION 1504 If defined, hardware flash sectors protection is used 1505 instead of U-Boot software protection. 1506 1507- CFG_DIRECT_FLASH_TFTP: 1508 1509 Enable TFTP transfers directly to flash memory; 1510 without this option such a download has to be 1511 performed in two steps: (1) download to RAM, and (2) 1512 copy from RAM to flash. 1513 1514 The two-step approach is usually more reliable, since 1515 you can check if the download worked before you erase 1516 the flash, but in some situations (when sytem RAM is 1517 too limited to allow for a tempory copy of the 1518 downloaded image) this option may be very useful. 1519 1520- CFG_FLASH_CFI: 1521 Define if the flash driver uses extra elements in the 1522 common flash structure for storing flash geometry. 1523 1524- CFG_FLASH_CFI_DRIVER 1525 This option also enables the building of the cfi_flash driver 1526 in the drivers directory 1527 1528- CFG_RX_ETH_BUFFER: 1529 Defines the number of ethernet receive buffers. On some 1530 ethernet controllers it is recommended to set this value 1531 to 8 or even higher (EEPRO100 or 405 EMAC), since all 1532 buffers can be full shortly after enabling the interface 1533 on high ethernet traffic. 1534 Defaults to 4 if not defined. 1535 1536The following definitions that deal with the placement and management 1537of environment data (variable area); in general, we support the 1538following configurations: 1539 1540- CFG_ENV_IS_IN_FLASH: 1541 1542 Define this if the environment is in flash memory. 1543 1544 a) The environment occupies one whole flash sector, which is 1545 "embedded" in the text segment with the U-Boot code. This 1546 happens usually with "bottom boot sector" or "top boot 1547 sector" type flash chips, which have several smaller 1548 sectors at the start or the end. For instance, such a 1549 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 1550 such a case you would place the environment in one of the 1551 4 kB sectors - with U-Boot code before and after it. With 1552 "top boot sector" type flash chips, you would put the 1553 environment in one of the last sectors, leaving a gap 1554 between U-Boot and the environment. 1555 1556 - CFG_ENV_OFFSET: 1557 1558 Offset of environment data (variable area) to the 1559 beginning of flash memory; for instance, with bottom boot 1560 type flash chips the second sector can be used: the offset 1561 for this sector is given here. 1562 1563 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 1564 1565 - CFG_ENV_ADDR: 1566 1567 This is just another way to specify the start address of 1568 the flash sector containing the environment (instead of 1569 CFG_ENV_OFFSET). 1570 1571 - CFG_ENV_SECT_SIZE: 1572 1573 Size of the sector containing the environment. 1574 1575 1576 b) Sometimes flash chips have few, equal sized, BIG sectors. 1577 In such a case you don't want to spend a whole sector for 1578 the environment. 1579 1580 - CFG_ENV_SIZE: 1581 1582 If you use this in combination with CFG_ENV_IS_IN_FLASH 1583 and CFG_ENV_SECT_SIZE, you can specify to use only a part 1584 of this flash sector for the environment. This saves 1585 memory for the RAM copy of the environment. 1586 1587 It may also save flash memory if you decide to use this 1588 when your environment is "embedded" within U-Boot code, 1589 since then the remainder of the flash sector could be used 1590 for U-Boot code. It should be pointed out that this is 1591 STRONGLY DISCOURAGED from a robustness point of view: 1592 updating the environment in flash makes it always 1593 necessary to erase the WHOLE sector. If something goes 1594 wrong before the contents has been restored from a copy in 1595 RAM, your target system will be dead. 1596 1597 - CFG_ENV_ADDR_REDUND 1598 CFG_ENV_SIZE_REDUND 1599 1600 These settings describe a second storage area used to hold 1601 a redundand copy of the environment data, so that there is 1602 a valid backup copy in case there is a power failure during 1603 a "saveenv" operation. 1604 1605BE CAREFUL! Any changes to the flash layout, and some changes to the 1606source code will make it necessary to adapt <board>/u-boot.lds* 1607accordingly! 1608 1609 1610- CFG_ENV_IS_IN_NVRAM: 1611 1612 Define this if you have some non-volatile memory device 1613 (NVRAM, battery buffered SRAM) which you want to use for the 1614 environment. 1615 1616 - CFG_ENV_ADDR: 1617 - CFG_ENV_SIZE: 1618 1619 These two #defines are used to determin the memory area you 1620 want to use for environment. It is assumed that this memory 1621 can just be read and written to, without any special 1622 provision. 1623 1624BE CAREFUL! The first access to the environment happens quite early 1625in U-Boot initalization (when we try to get the setting of for the 1626console baudrate). You *MUST* have mappend your NVRAM area then, or 1627U-Boot will hang. 1628 1629Please note that even with NVRAM we still use a copy of the 1630environment in RAM: we could work on NVRAM directly, but we want to 1631keep settings there always unmodified except somebody uses "saveenv" 1632to save the current settings. 1633 1634 1635- CFG_ENV_IS_IN_EEPROM: 1636 1637 Use this if you have an EEPROM or similar serial access 1638 device and a driver for it. 1639 1640 - CFG_ENV_OFFSET: 1641 - CFG_ENV_SIZE: 1642 1643 These two #defines specify the offset and size of the 1644 environment area within the total memory of your EEPROM. 1645 1646 - CFG_I2C_EEPROM_ADDR: 1647 If defined, specified the chip address of the EEPROM device. 1648 The default address is zero. 1649 1650 - CFG_EEPROM_PAGE_WRITE_BITS: 1651 If defined, the number of bits used to address bytes in a 1652 single page in the EEPROM device. A 64 byte page, for example 1653 would require six bits. 1654 1655 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 1656 If defined, the number of milliseconds to delay between 1657 page writes. The default is zero milliseconds. 1658 1659 - CFG_I2C_EEPROM_ADDR_LEN: 1660 The length in bytes of the EEPROM memory array address. Note 1661 that this is NOT the chip address length! 1662 1663 - CFG_EEPROM_SIZE: 1664 The size in bytes of the EEPROM device. 1665 1666 1667- CFG_ENV_IS_IN_DATAFLASH: 1668 1669 Define this if you have a DataFlash memory device which you 1670 want to use for the environment. 1671 1672 - CFG_ENV_OFFSET: 1673 - CFG_ENV_ADDR: 1674 - CFG_ENV_SIZE: 1675 1676 These three #defines specify the offset and size of the 1677 environment area within the total memory of your DataFlash placed 1678 at the specified address. 1679 1680 1681- CFG_SPI_INIT_OFFSET 1682 1683 Defines offset to the initial SPI buffer area in DPRAM. The 1684 area is used at an early stage (ROM part) if the environment 1685 is configured to reside in the SPI EEPROM: We need a 520 byte 1686 scratch DPRAM area. It is used between the two initialization 1687 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 1688 to be a good choice since it makes it far enough from the 1689 start of the data area as well as from the stack pointer. 1690 1691Please note that the environment is read-only as long as the monitor 1692has been relocated to RAM and a RAM copy of the environment has been 1693created; also, when using EEPROM you will have to use getenv_r() 1694until then to read environment variables. 1695 1696The environment is protected by a CRC32 checksum. Before the monitor 1697is relocated into RAM, as a result of a bad CRC you will be working 1698with the compiled-in default environment - *silently*!!! [This is 1699necessary, because the first environment variable we need is the 1700"baudrate" setting for the console - if we have a bad CRC, we don't 1701have any device yet where we could complain.] 1702 1703Note: once the monitor has been relocated, then it will complain if 1704the default environment is used; a new CRC is computed as soon as you 1705use the "saveenv" command to store a valid environment. 1706 1707- CFG_FAULT_ECHO_LINK_DOWN: 1708 Echo the inverted Ethernet link state to the fault LED. 1709 1710 Note: If this option is active, then CFG_FAULT_MII_ADDR 1711 also needs to be defined. 1712 1713- CFG_FAULT_MII_ADDR: 1714 MII address of the PHY to check for the Ethernet link state. 1715 1716Low Level (hardware related) configuration options: 1717--------------------------------------------------- 1718 1719- CFG_CACHELINE_SIZE: 1720 Cache Line Size of the CPU. 1721 1722- CFG_DEFAULT_IMMR: 1723 Default address of the IMMR after system reset. 1724 1725 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 1726 and RPXsuper) to be able to adjust the position of 1727 the IMMR register after a reset. 1728 1729- Floppy Disk Support: 1730 CFG_FDC_DRIVE_NUMBER 1731 1732 the default drive number (default value 0) 1733 1734 CFG_ISA_IO_STRIDE 1735 1736 defines the spacing between fdc chipset registers 1737 (default value 1) 1738 1739 CFG_ISA_IO_OFFSET 1740 1741 defines the offset of register from address. It 1742 depends on which part of the data bus is connected to 1743 the fdc chipset. (default value 0) 1744 1745 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 1746 CFG_FDC_DRIVE_NUMBER are undefined, they take their 1747 default value. 1748 1749 if CFG_FDC_HW_INIT is defined, then the function 1750 fdc_hw_init() is called at the beginning of the FDC 1751 setup. fdc_hw_init() must be provided by the board 1752 source code. It is used to make hardware dependant 1753 initializations. 1754 1755- CFG_IMMR: Physical address of the Internal Memory Mapped 1756 Register; DO NOT CHANGE! (11-4) 1757 [MPC8xx systems only] 1758 1759- CFG_INIT_RAM_ADDR: 1760 1761 Start address of memory area that can be used for 1762 initial data and stack; please note that this must be 1763 writable memory that is working WITHOUT special 1764 initialization, i. e. you CANNOT use normal RAM which 1765 will become available only after programming the 1766 memory controller and running certain initialization 1767 sequences. 1768 1769 U-Boot uses the following memory types: 1770 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 1771 - MPC824X: data cache 1772 - PPC4xx: data cache 1773 1774- CFG_GBL_DATA_OFFSET: 1775 1776 Offset of the initial data structure in the memory 1777 area defined by CFG_INIT_RAM_ADDR. Usually 1778 CFG_GBL_DATA_OFFSET is chosen such that the initial 1779 data is located at the end of the available space 1780 (sometimes written as (CFG_INIT_RAM_END - 1781 CFG_INIT_DATA_SIZE), and the initial stack is just 1782 below that area (growing from (CFG_INIT_RAM_ADDR + 1783 CFG_GBL_DATA_OFFSET) downward. 1784 1785 Note: 1786 On the MPC824X (or other systems that use the data 1787 cache for initial memory) the address chosen for 1788 CFG_INIT_RAM_ADDR is basically arbitrary - it must 1789 point to an otherwise UNUSED address space between 1790 the top of RAM and the start of the PCI space. 1791 1792- CFG_SIUMCR: SIU Module Configuration (11-6) 1793 1794- CFG_SYPCR: System Protection Control (11-9) 1795 1796- CFG_TBSCR: Time Base Status and Control (11-26) 1797 1798- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 1799 1800- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 1801 1802- CFG_SCCR: System Clock and reset Control Register (15-27) 1803 1804- CFG_OR_TIMING_SDRAM: 1805 SDRAM timing 1806 1807- CFG_MAMR_PTA: 1808 periodic timer for refresh 1809 1810- CFG_DER: Debug Event Register (37-47) 1811 1812- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 1813 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 1814 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 1815 CFG_BR1_PRELIM: 1816 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 1817 1818- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 1819 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 1820 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 1821 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 1822 1823- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 1824 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 1825 Machine Mode Register and Memory Periodic Timer 1826 Prescaler definitions (SDRAM timing) 1827 1828- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 1829 enable I2C microcode relocation patch (MPC8xx); 1830 define relocation offset in DPRAM [DSP2] 1831 1832- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 1833 enable SPI microcode relocation patch (MPC8xx); 1834 define relocation offset in DPRAM [SCC4] 1835 1836- CFG_USE_OSCCLK: 1837 Use OSCM clock mode on MBX8xx board. Be careful, 1838 wrong setting might damage your board. Read 1839 doc/README.MBX before setting this variable! 1840 1841- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 1842 Offset of the bootmode word in DPRAM used by post 1843 (Power On Self Tests). This definition overrides 1844 #define'd default value in commproc.h resp. 1845 cpm_8260.h. 1846 1847- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 1848 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 1849 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 1850 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 1851 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 1852 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 1853 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 1854 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 1855 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 1856 1857Building the Software: 1858====================== 1859 1860Building U-Boot has been tested in native PPC environments (on a 1861PowerBook G3 running LinuxPPC 2000) and in cross environments 1862(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and 1863NetBSD 1.5 on x86). 1864 1865If you are not using a native PPC environment, it is assumed that you 1866have the GNU cross compiling tools available in your path and named 1867with a prefix of "powerpc-linux-". If this is not the case, (e.g. if 1868you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change 1869the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU, 1870change it to: 1871 1872 CROSS_COMPILE = ppc_4xx- 1873 1874 1875U-Boot is intended to be simple to build. After installing the 1876sources you must configure U-Boot for one specific board type. This 1877is done by typing: 1878 1879 make NAME_config 1880 1881where "NAME_config" is the name of one of the existing 1882configurations; the following names are supported: 1883 1884 ADCIOP_config GTH_config TQM850L_config 1885 ADS860_config IP860_config TQM855L_config 1886 AR405_config IVML24_config TQM860L_config 1887 CANBT_config IVMS8_config WALNUT405_config 1888 CPCI405_config LANTEC_config cogent_common_config 1889 CPCIISER4_config MBX_config cogent_mpc8260_config 1890 CU824_config MBX860T_config cogent_mpc8xx_config 1891 ESTEEM192E_config RPXlite_config hermes_config 1892 ETX094_config RPXsuper_config hymod_config 1893 FADS823_config SM850_config lwmon_config 1894 FADS850SAR_config SPD823TS_config pcu_e_config 1895 FADS860T_config SXNI855T_config rsdproto_config 1896 FPS850L_config Sandpoint8240_config sbc8260_config 1897 GENIETV_config TQM823L_config PIP405_config 1898 GEN860T_config EBONY_config FPS860L_config 1899 ELPT860_config cmi_mpc5xx_config NETVIA_config 1900 at91rm9200dk_config omap1510inn_config MPC8260ADS_config 1901 omap1610inn_config ZPC1900_config MPC8540ADS_config 1902 MPC8560ADS_config QS850_config QS823_config 1903 QS860T_config DUET_ADS_config omap1610h2_config 1904 1905Note: for some board special configuration names may exist; check if 1906 additional information is available from the board vendor; for 1907 instance, the TQM8xxL systems run normally at 50 MHz and use a 1908 SCC for 10baseT ethernet; there are also systems with 80 MHz 1909 CPU clock, and an optional Fast Ethernet module is available 1910 for CPU's with FEC. You can select such additional "features" 1911 when chosing the configuration, i. e. 1912 1913 make TQM860L_config 1914 - will configure for a plain TQM860L, i. e. 50MHz, no FEC 1915 1916 make TQM860L_FEC_config 1917 - will configure for a TQM860L at 50MHz with FEC for ethernet 1918 1919 make TQM860L_80MHz_config 1920 - will configure for a TQM860L at 80 MHz, with normal 10baseT 1921 interface 1922 1923 make TQM860L_FEC_80MHz_config 1924 - will configure for a TQM860L at 80 MHz with FEC for ethernet 1925 1926 make TQM823L_LCD_config 1927 - will configure for a TQM823L with U-Boot console on LCD 1928 1929 make TQM823L_LCD_80MHz_config 1930 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD 1931 1932 etc. 1933 1934 1935Finally, type "make all", and you should get some working U-Boot 1936images ready for download to / installation on your system: 1937 1938- "u-boot.bin" is a raw binary image 1939- "u-boot" is an image in ELF binary format 1940- "u-boot.srec" is in Motorola S-Record format 1941 1942 1943Please be aware that the Makefiles assume you are using GNU make, so 1944for instance on NetBSD you might need to use "gmake" instead of 1945native "make". 1946 1947 1948If the system board that you have is not listed, then you will need 1949to port U-Boot to your hardware platform. To do this, follow these 1950steps: 1951 19521. Add a new configuration option for your board to the toplevel 1953 "Makefile" and to the "MAKEALL" script, using the existing 1954 entries as examples. Note that here and at many other places 1955 boards and other names are listed in alphabetical sort order. Please 1956 keep this order. 19572. Create a new directory to hold your board specific code. Add any 1958 files you need. In your board directory, you will need at least 1959 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 19603. Create a new configuration file "include/configs/<board>.h" for 1961 your board 19623. If you're porting U-Boot to a new CPU, then also create a new 1963 directory to hold your CPU specific code. Add any files you need. 19644. Run "make <board>_config" with your new name. 19655. Type "make", and you should get a working "u-boot.srec" file 1966 to be installed on your target system. 19676. Debug and solve any problems that might arise. 1968 [Of course, this last step is much harder than it sounds.] 1969 1970 1971Testing of U-Boot Modifications, Ports to New Hardware, etc.: 1972============================================================== 1973 1974If you have modified U-Boot sources (for instance added a new board 1975or support for new devices, a new CPU, etc.) you are expected to 1976provide feedback to the other developers. The feedback normally takes 1977the form of a "patch", i. e. a context diff against a certain (latest 1978official or latest in CVS) version of U-Boot sources. 1979 1980But before you submit such a patch, please verify that your modifi- 1981cation did not break existing code. At least make sure that *ALL* of 1982the supported boards compile WITHOUT ANY compiler warnings. To do so, 1983just run the "MAKEALL" script, which will configure and build U-Boot 1984for ALL supported system. Be warned, this will take a while. You can 1985select which (cross) compiler to use by passing a `CROSS_COMPILE' 1986environment variable to the script, i. e. to use the cross tools from 1987MontaVista's Hard Hat Linux you can type 1988 1989 CROSS_COMPILE=ppc_8xx- MAKEALL 1990 1991or to build on a native PowerPC system you can type 1992 1993 CROSS_COMPILE=' ' MAKEALL 1994 1995See also "U-Boot Porting Guide" below. 1996 1997 1998Monitor Commands - Overview: 1999============================ 2000 2001go - start application at address 'addr' 2002run - run commands in an environment variable 2003bootm - boot application image from memory 2004bootp - boot image via network using BootP/TFTP protocol 2005tftpboot- boot image via network using TFTP protocol 2006 and env variables "ipaddr" and "serverip" 2007 (and eventually "gatewayip") 2008rarpboot- boot image via network using RARP/TFTP protocol 2009diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2010loads - load S-Record file over serial line 2011loadb - load binary file over serial line (kermit mode) 2012md - memory display 2013mm - memory modify (auto-incrementing) 2014nm - memory modify (constant address) 2015mw - memory write (fill) 2016cp - memory copy 2017cmp - memory compare 2018crc32 - checksum calculation 2019imd - i2c memory display 2020imm - i2c memory modify (auto-incrementing) 2021inm - i2c memory modify (constant address) 2022imw - i2c memory write (fill) 2023icrc32 - i2c checksum calculation 2024iprobe - probe to discover valid I2C chip addresses 2025iloop - infinite loop on address range 2026isdram - print SDRAM configuration information 2027sspi - SPI utility commands 2028base - print or set address offset 2029printenv- print environment variables 2030setenv - set environment variables 2031saveenv - save environment variables to persistent storage 2032protect - enable or disable FLASH write protection 2033erase - erase FLASH memory 2034flinfo - print FLASH memory information 2035bdinfo - print Board Info structure 2036iminfo - print header information for application image 2037coninfo - print console devices and informations 2038ide - IDE sub-system 2039loop - infinite loop on address range 2040mtest - simple RAM test 2041icache - enable or disable instruction cache 2042dcache - enable or disable data cache 2043reset - Perform RESET of the CPU 2044echo - echo args to console 2045version - print monitor version 2046help - print online help 2047? - alias for 'help' 2048 2049 2050Monitor Commands - Detailed Description: 2051======================================== 2052 2053TODO. 2054 2055For now: just type "help <command>". 2056 2057 2058Environment Variables: 2059====================== 2060 2061U-Boot supports user configuration using Environment Variables which 2062can be made persistent by saving to Flash memory. 2063 2064Environment Variables are set using "setenv", printed using 2065"printenv", and saved to Flash using "saveenv". Using "setenv" 2066without a value can be used to delete a variable from the 2067environment. As long as you don't save the environment you are 2068working with an in-memory copy. In case the Flash area containing the 2069environment is erased by accident, a default environment is provided. 2070 2071Some configuration options can be set using Environment Variables: 2072 2073 baudrate - see CONFIG_BAUDRATE 2074 2075 bootdelay - see CONFIG_BOOTDELAY 2076 2077 bootcmd - see CONFIG_BOOTCOMMAND 2078 2079 bootargs - Boot arguments when booting an RTOS image 2080 2081 bootfile - Name of the image to load with TFTP 2082 2083 autoload - if set to "no" (any string beginning with 'n'), 2084 "bootp" will just load perform a lookup of the 2085 configuration from the BOOTP server, but not try to 2086 load any image using TFTP 2087 2088 autostart - if set to "yes", an image loaded using the "bootp", 2089 "rarpboot", "tftpboot" or "diskboot" commands will 2090 be automatically started (by internally calling 2091 "bootm") 2092 2093 If set to "no", a standalone image passed to the 2094 "bootm" command will be copied to the load address 2095 (and eventually uncompressed), but NOT be started. 2096 This can be used to load and uncompress arbitrary 2097 data. 2098 2099 initrd_high - restrict positioning of initrd images: 2100 If this variable is not set, initrd images will be 2101 copied to the highest possible address in RAM; this 2102 is usually what you want since it allows for 2103 maximum initrd size. If for some reason you want to 2104 make sure that the initrd image is loaded below the 2105 CFG_BOOTMAPSZ limit, you can set this environment 2106 variable to a value of "no" or "off" or "0". 2107 Alternatively, you can set it to a maximum upper 2108 address to use (U-Boot will still check that it 2109 does not overwrite the U-Boot stack and data). 2110 2111 For instance, when you have a system with 16 MB 2112 RAM, and want to reserve 4 MB from use by Linux, 2113 you can do this by adding "mem=12M" to the value of 2114 the "bootargs" variable. However, now you must make 2115 sure that the initrd image is placed in the first 2116 12 MB as well - this can be done with 2117 2118 setenv initrd_high 00c00000 2119 2120 If you set initrd_high to 0xFFFFFFFF, this is an 2121 indication to U-Boot that all addresses are legal 2122 for the Linux kernel, including addresses in flash 2123 memory. In this case U-Boot will NOT COPY the 2124 ramdisk at all. This may be useful to reduce the 2125 boot time on your system, but requires that this 2126 feature is supported by your Linux kernel. 2127 2128 ipaddr - IP address; needed for tftpboot command 2129 2130 loadaddr - Default load address for commands like "bootp", 2131 "rarpboot", "tftpboot", "loadb" or "diskboot" 2132 2133 loads_echo - see CONFIG_LOADS_ECHO 2134 2135 serverip - TFTP server IP address; needed for tftpboot command 2136 2137 bootretry - see CONFIG_BOOT_RETRY_TIME 2138 2139 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2140 2141 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2142 2143 2144The following environment variables may be used and automatically 2145updated by the network boot commands ("bootp" and "rarpboot"), 2146depending the information provided by your boot server: 2147 2148 bootfile - see above 2149 dnsip - IP address of your Domain Name Server 2150 dnsip2 - IP address of your secondary Domain Name Server 2151 gatewayip - IP address of the Gateway (Router) to use 2152 hostname - Target hostname 2153 ipaddr - see above 2154 netmask - Subnet Mask 2155 rootpath - Pathname of the root filesystem on the NFS server 2156 serverip - see above 2157 2158 2159There are two special Environment Variables: 2160 2161 serial# - contains hardware identification information such 2162 as type string and/or serial number 2163 ethaddr - Ethernet address 2164 2165These variables can be set only once (usually during manufacturing of 2166the board). U-Boot refuses to delete or overwrite these variables 2167once they have been set once. 2168 2169 2170Further special Environment Variables: 2171 2172 ver - Contains the U-Boot version string as printed 2173 with the "version" command. This variable is 2174 readonly (see CONFIG_VERSION_VARIABLE). 2175 2176 2177Please note that changes to some configuration parameters may take 2178only effect after the next boot (yes, that's just like Windoze :-). 2179 2180 2181Command Line Parsing: 2182===================== 2183 2184There are two different command line parsers available with U-Boot: 2185the old "simple" one, and the much more powerful "hush" shell: 2186 2187Old, simple command line parser: 2188-------------------------------- 2189 2190- supports environment variables (through setenv / saveenv commands) 2191- several commands on one line, separated by ';' 2192- variable substitution using "... $(name) ..." syntax 2193- special characters ('$', ';') can be escaped by prefixing with '\', 2194 for example: 2195 setenv bootcmd bootm \$(address) 2196- You can also escape text by enclosing in single apostrophes, for example: 2197 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2198 2199Hush shell: 2200----------- 2201 2202- similar to Bourne shell, with control structures like 2203 if...then...else...fi, for...do...done; while...do...done, 2204 until...do...done, ... 2205- supports environment ("global") variables (through setenv / saveenv 2206 commands) and local shell variables (through standard shell syntax 2207 "name=value"); only environment variables can be used with "run" 2208 command 2209 2210General rules: 2211-------------- 2212 2213(1) If a command line (or an environment variable executed by a "run" 2214 command) contains several commands separated by semicolon, and 2215 one of these commands fails, then the remaining commands will be 2216 executed anyway. 2217 2218(2) If you execute several variables with one call to run (i. e. 2219 calling run with a list af variables as arguments), any failing 2220 command will cause "run" to terminate, i. e. the remaining 2221 variables are not executed. 2222 2223Note for Redundant Ethernet Interfaces: 2224======================================= 2225 2226Some boards come with redundant ethernet interfaces; U-Boot supports 2227such configurations and is capable of automatic selection of a 2228"working" interface when needed. MAC assignment works as follows: 2229 2230Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2231MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2232"eth1addr" (=>eth1), "eth2addr", ... 2233 2234If the network interface stores some valid MAC address (for instance 2235in SROM), this is used as default address if there is NO correspon- 2236ding setting in the environment; if the corresponding environment 2237variable is set, this overrides the settings in the card; that means: 2238 2239o If the SROM has a valid MAC address, and there is no address in the 2240 environment, the SROM's address is used. 2241 2242o If there is no valid address in the SROM, and a definition in the 2243 environment exists, then the value from the environment variable is 2244 used. 2245 2246o If both the SROM and the environment contain a MAC address, and 2247 both addresses are the same, this MAC address is used. 2248 2249o If both the SROM and the environment contain a MAC address, and the 2250 addresses differ, the value from the environment is used and a 2251 warning is printed. 2252 2253o If neither SROM nor the environment contain a MAC address, an error 2254 is raised. 2255 2256 2257Image Formats: 2258============== 2259 2260The "boot" commands of this monitor operate on "image" files which 2261can be basicly anything, preceeded by a special header; see the 2262definitions in include/image.h for details; basicly, the header 2263defines the following image properties: 2264 2265* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2266 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2267 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2268 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2269* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86, 2270 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2271 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC). 2272* Compression Type (uncompressed, gzip, bzip2) 2273* Load Address 2274* Entry Point 2275* Image Name 2276* Image Timestamp 2277 2278The header is marked by a special Magic Number, and both the header 2279and the data portions of the image are secured against corruption by 2280CRC32 checksums. 2281 2282 2283Linux Support: 2284============== 2285 2286Although U-Boot should support any OS or standalone application 2287easily, the main focus has always been on Linux during the design of 2288U-Boot. 2289 2290U-Boot includes many features that so far have been part of some 2291special "boot loader" code within the Linux kernel. Also, any 2292"initrd" images to be used are no longer part of one big Linux image; 2293instead, kernel and "initrd" are separate images. This implementation 2294serves several purposes: 2295 2296- the same features can be used for other OS or standalone 2297 applications (for instance: using compressed images to reduce the 2298 Flash memory footprint) 2299 2300- it becomes much easier to port new Linux kernel versions because 2301 lots of low-level, hardware dependent stuff are done by U-Boot 2302 2303- the same Linux kernel image can now be used with different "initrd" 2304 images; of course this also means that different kernel images can 2305 be run with the same "initrd". This makes testing easier (you don't 2306 have to build a new "zImage.initrd" Linux image when you just 2307 change a file in your "initrd"). Also, a field-upgrade of the 2308 software is easier now. 2309 2310 2311Linux HOWTO: 2312============ 2313 2314Porting Linux to U-Boot based systems: 2315--------------------------------------- 2316 2317U-Boot cannot save you from doing all the necessary modifications to 2318configure the Linux device drivers for use with your target hardware 2319(no, we don't intend to provide a full virtual machine interface to 2320Linux :-). 2321 2322But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 2323 2324Just make sure your machine specific header file (for instance 2325include/asm-ppc/tqm8xx.h) includes the same definition of the Board 2326Information structure as we define in include/u-boot.h, and make 2327sure that your definition of IMAP_ADDR uses the same value as your 2328U-Boot configuration in CFG_IMMR. 2329 2330 2331Configuring the Linux kernel: 2332----------------------------- 2333 2334No specific requirements for U-Boot. Make sure you have some root 2335device (initial ramdisk, NFS) for your target system. 2336 2337 2338Building a Linux Image: 2339----------------------- 2340 2341With U-Boot, "normal" build targets like "zImage" or "bzImage" are 2342not used. If you use recent kernel source, a new build target 2343"uImage" will exist which automatically builds an image usable by 2344U-Boot. Most older kernels also have support for a "pImage" target, 2345which was introduced for our predecessor project PPCBoot and uses a 2346100% compatible format. 2347 2348Example: 2349 2350 make TQM850L_config 2351 make oldconfig 2352 make dep 2353 make uImage 2354 2355The "uImage" build target uses a special tool (in 'tools/mkimage') to 2356encapsulate a compressed Linux kernel image with header information, 2357CRC32 checksum etc. for use with U-Boot. This is what we are doing: 2358 2359* build a standard "vmlinux" kernel image (in ELF binary format): 2360 2361* convert the kernel into a raw binary image: 2362 2363 ${CROSS_COMPILE}-objcopy -O binary \ 2364 -R .note -R .comment \ 2365 -S vmlinux linux.bin 2366 2367* compress the binary image: 2368 2369 gzip -9 linux.bin 2370 2371* package compressed binary image for U-Boot: 2372 2373 mkimage -A ppc -O linux -T kernel -C gzip \ 2374 -a 0 -e 0 -n "Linux Kernel Image" \ 2375 -d linux.bin.gz uImage 2376 2377 2378The "mkimage" tool can also be used to create ramdisk images for use 2379with U-Boot, either separated from the Linux kernel image, or 2380combined into one file. "mkimage" encapsulates the images with a 64 2381byte header containing information about target architecture, 2382operating system, image type, compression method, entry points, time 2383stamp, CRC32 checksums, etc. 2384 2385"mkimage" can be called in two ways: to verify existing images and 2386print the header information, or to build new images. 2387 2388In the first form (with "-l" option) mkimage lists the information 2389contained in the header of an existing U-Boot image; this includes 2390checksum verification: 2391 2392 tools/mkimage -l image 2393 -l ==> list image header information 2394 2395The second form (with "-d" option) is used to build a U-Boot image 2396from a "data file" which is used as image payload: 2397 2398 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 2399 -n name -d data_file image 2400 -A ==> set architecture to 'arch' 2401 -O ==> set operating system to 'os' 2402 -T ==> set image type to 'type' 2403 -C ==> set compression type 'comp' 2404 -a ==> set load address to 'addr' (hex) 2405 -e ==> set entry point to 'ep' (hex) 2406 -n ==> set image name to 'name' 2407 -d ==> use image data from 'datafile' 2408 2409Right now, all Linux kernels use the same load address (0x00000000), 2410but the entry point address depends on the kernel version: 2411 2412- 2.2.x kernels have the entry point at 0x0000000C, 2413- 2.3.x and later kernels have the entry point at 0x00000000. 2414 2415So a typical call to build a U-Boot image would read: 2416 2417 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2418 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 2419 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 2420 > examples/uImage.TQM850L 2421 Image Name: 2.4.4 kernel for TQM850L 2422 Created: Wed Jul 19 02:34:59 2000 2423 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2424 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2425 Load Address: 0x00000000 2426 Entry Point: 0x00000000 2427 2428To verify the contents of the image (or check for corruption): 2429 2430 -> tools/mkimage -l examples/uImage.TQM850L 2431 Image Name: 2.4.4 kernel for TQM850L 2432 Created: Wed Jul 19 02:34:59 2000 2433 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2434 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2435 Load Address: 0x00000000 2436 Entry Point: 0x00000000 2437 2438NOTE: for embedded systems where boot time is critical you can trade 2439speed for memory and install an UNCOMPRESSED image instead: this 2440needs more space in Flash, but boots much faster since it does not 2441need to be uncompressed: 2442 2443 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 2444 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2445 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 2446 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 2447 > examples/uImage.TQM850L-uncompressed 2448 Image Name: 2.4.4 kernel for TQM850L 2449 Created: Wed Jul 19 02:34:59 2000 2450 Image Type: PowerPC Linux Kernel Image (uncompressed) 2451 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 2452 Load Address: 0x00000000 2453 Entry Point: 0x00000000 2454 2455 2456Similar you can build U-Boot images from a 'ramdisk.image.gz' file 2457when your kernel is intended to use an initial ramdisk: 2458 2459 -> tools/mkimage -n 'Simple Ramdisk Image' \ 2460 > -A ppc -O linux -T ramdisk -C gzip \ 2461 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 2462 Image Name: Simple Ramdisk Image 2463 Created: Wed Jan 12 14:01:50 2000 2464 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2465 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 2466 Load Address: 0x00000000 2467 Entry Point: 0x00000000 2468 2469 2470Installing a Linux Image: 2471------------------------- 2472 2473To downloading a U-Boot image over the serial (console) interface, 2474you must convert the image to S-Record format: 2475 2476 objcopy -I binary -O srec examples/image examples/image.srec 2477 2478The 'objcopy' does not understand the information in the U-Boot 2479image header, so the resulting S-Record file will be relative to 2480address 0x00000000. To load it to a given address, you need to 2481specify the target address as 'offset' parameter with the 'loads' 2482command. 2483 2484Example: install the image to address 0x40100000 (which on the 2485TQM8xxL is in the first Flash bank): 2486 2487 => erase 40100000 401FFFFF 2488 2489 .......... done 2490 Erased 8 sectors 2491 2492 => loads 40100000 2493 ## Ready for S-Record download ... 2494 ~>examples/image.srec 2495 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 2496 ... 2497 15989 15990 15991 15992 2498 [file transfer complete] 2499 [connected] 2500 ## Start Addr = 0x00000000 2501 2502 2503You can check the success of the download using the 'iminfo' command; 2504this includes a checksum verification so you can be sure no data 2505corruption happened: 2506 2507 => imi 40100000 2508 2509 ## Checking Image at 40100000 ... 2510 Image Name: 2.2.13 for initrd on TQM850L 2511 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2512 Data Size: 335725 Bytes = 327 kB = 0 MB 2513 Load Address: 00000000 2514 Entry Point: 0000000c 2515 Verifying Checksum ... OK 2516 2517 2518Boot Linux: 2519----------- 2520 2521The "bootm" command is used to boot an application that is stored in 2522memory (RAM or Flash). In case of a Linux kernel image, the contents 2523of the "bootargs" environment variable is passed to the kernel as 2524parameters. You can check and modify this variable using the 2525"printenv" and "setenv" commands: 2526 2527 2528 => printenv bootargs 2529 bootargs=root=/dev/ram 2530 2531 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2532 2533 => printenv bootargs 2534 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2535 2536 => bootm 40020000 2537 ## Booting Linux kernel at 40020000 ... 2538 Image Name: 2.2.13 for NFS on TQM850L 2539 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2540 Data Size: 381681 Bytes = 372 kB = 0 MB 2541 Load Address: 00000000 2542 Entry Point: 0000000c 2543 Verifying Checksum ... OK 2544 Uncompressing Kernel Image ... OK 2545 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 2546 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2547 time_init: decrementer frequency = 187500000/60 2548 Calibrating delay loop... 49.77 BogoMIPS 2549 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 2550 ... 2551 2552If you want to boot a Linux kernel with initial ram disk, you pass 2553the memory addresses of both the kernel and the initrd image (PPBCOOT 2554format!) to the "bootm" command: 2555 2556 => imi 40100000 40200000 2557 2558 ## Checking Image at 40100000 ... 2559 Image Name: 2.2.13 for initrd on TQM850L 2560 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2561 Data Size: 335725 Bytes = 327 kB = 0 MB 2562 Load Address: 00000000 2563 Entry Point: 0000000c 2564 Verifying Checksum ... OK 2565 2566 ## Checking Image at 40200000 ... 2567 Image Name: Simple Ramdisk Image 2568 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2569 Data Size: 566530 Bytes = 553 kB = 0 MB 2570 Load Address: 00000000 2571 Entry Point: 00000000 2572 Verifying Checksum ... OK 2573 2574 => bootm 40100000 40200000 2575 ## Booting Linux kernel at 40100000 ... 2576 Image Name: 2.2.13 for initrd on TQM850L 2577 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2578 Data Size: 335725 Bytes = 327 kB = 0 MB 2579 Load Address: 00000000 2580 Entry Point: 0000000c 2581 Verifying Checksum ... OK 2582 Uncompressing Kernel Image ... OK 2583 ## Loading RAMDisk Image at 40200000 ... 2584 Image Name: Simple Ramdisk Image 2585 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2586 Data Size: 566530 Bytes = 553 kB = 0 MB 2587 Load Address: 00000000 2588 Entry Point: 00000000 2589 Verifying Checksum ... OK 2590 Loading Ramdisk ... OK 2591 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 2592 Boot arguments: root=/dev/ram 2593 time_init: decrementer frequency = 187500000/60 2594 Calibrating delay loop... 49.77 BogoMIPS 2595 ... 2596 RAMDISK: Compressed image found at block 0 2597 VFS: Mounted root (ext2 filesystem). 2598 2599 bash# 2600 2601More About U-Boot Image Types: 2602------------------------------ 2603 2604U-Boot supports the following image types: 2605 2606 "Standalone Programs" are directly runnable in the environment 2607 provided by U-Boot; it is expected that (if they behave 2608 well) you can continue to work in U-Boot after return from 2609 the Standalone Program. 2610 "OS Kernel Images" are usually images of some Embedded OS which 2611 will take over control completely. Usually these programs 2612 will install their own set of exception handlers, device 2613 drivers, set up the MMU, etc. - this means, that you cannot 2614 expect to re-enter U-Boot except by resetting the CPU. 2615 "RAMDisk Images" are more or less just data blocks, and their 2616 parameters (address, size) are passed to an OS kernel that is 2617 being started. 2618 "Multi-File Images" contain several images, typically an OS 2619 (Linux) kernel image and one or more data images like 2620 RAMDisks. This construct is useful for instance when you want 2621 to boot over the network using BOOTP etc., where the boot 2622 server provides just a single image file, but you want to get 2623 for instance an OS kernel and a RAMDisk image. 2624 2625 "Multi-File Images" start with a list of image sizes, each 2626 image size (in bytes) specified by an "uint32_t" in network 2627 byte order. This list is terminated by an "(uint32_t)0". 2628 Immediately after the terminating 0 follow the images, one by 2629 one, all aligned on "uint32_t" boundaries (size rounded up to 2630 a multiple of 4 bytes). 2631 2632 "Firmware Images" are binary images containing firmware (like 2633 U-Boot or FPGA images) which usually will be programmed to 2634 flash memory. 2635 2636 "Script files" are command sequences that will be executed by 2637 U-Boot's command interpreter; this feature is especially 2638 useful when you configure U-Boot to use a real shell (hush) 2639 as command interpreter. 2640 2641 2642Standalone HOWTO: 2643================= 2644 2645One of the features of U-Boot is that you can dynamically load and 2646run "standalone" applications, which can use some resources of 2647U-Boot like console I/O functions or interrupt services. 2648 2649Two simple examples are included with the sources: 2650 2651"Hello World" Demo: 2652------------------- 2653 2654'examples/hello_world.c' contains a small "Hello World" Demo 2655application; it is automatically compiled when you build U-Boot. 2656It's configured to run at address 0x00040004, so you can play with it 2657like that: 2658 2659 => loads 2660 ## Ready for S-Record download ... 2661 ~>examples/hello_world.srec 2662 1 2 3 4 5 6 7 8 9 10 11 ... 2663 [file transfer complete] 2664 [connected] 2665 ## Start Addr = 0x00040004 2666 2667 => go 40004 Hello World! This is a test. 2668 ## Starting application at 0x00040004 ... 2669 Hello World 2670 argc = 7 2671 argv[0] = "40004" 2672 argv[1] = "Hello" 2673 argv[2] = "World!" 2674 argv[3] = "This" 2675 argv[4] = "is" 2676 argv[5] = "a" 2677 argv[6] = "test." 2678 argv[7] = "<NULL>" 2679 Hit any key to exit ... 2680 2681 ## Application terminated, rc = 0x0 2682 2683Another example, which demonstrates how to register a CPM interrupt 2684handler with the U-Boot code, can be found in 'examples/timer.c'. 2685Here, a CPM timer is set up to generate an interrupt every second. 2686The interrupt service routine is trivial, just printing a '.' 2687character, but this is just a demo program. The application can be 2688controlled by the following keys: 2689 2690 ? - print current values og the CPM Timer registers 2691 b - enable interrupts and start timer 2692 e - stop timer and disable interrupts 2693 q - quit application 2694 2695 => loads 2696 ## Ready for S-Record download ... 2697 ~>examples/timer.srec 2698 1 2 3 4 5 6 7 8 9 10 11 ... 2699 [file transfer complete] 2700 [connected] 2701 ## Start Addr = 0x00040004 2702 2703 => go 40004 2704 ## Starting application at 0x00040004 ... 2705 TIMERS=0xfff00980 2706 Using timer 1 2707 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 2708 2709Hit 'b': 2710 [q, b, e, ?] Set interval 1000000 us 2711 Enabling timer 2712Hit '?': 2713 [q, b, e, ?] ........ 2714 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 2715Hit '?': 2716 [q, b, e, ?] . 2717 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 2718Hit '?': 2719 [q, b, e, ?] . 2720 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 2721Hit '?': 2722 [q, b, e, ?] . 2723 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 2724Hit 'e': 2725 [q, b, e, ?] ...Stopping timer 2726Hit 'q': 2727 [q, b, e, ?] ## Application terminated, rc = 0x0 2728 2729 2730Minicom warning: 2731================ 2732 2733Over time, many people have reported problems when trying to use the 2734"minicom" terminal emulation program for serial download. I (wd) 2735consider minicom to be broken, and recommend not to use it. Under 2736Unix, I recommend to use C-Kermit for general purpose use (and 2737especially for kermit binary protocol download ("loadb" command), and 2738use "cu" for S-Record download ("loads" command). 2739 2740Nevertheless, if you absolutely want to use it try adding this 2741configuration to your "File transfer protocols" section: 2742 2743 Name Program Name U/D FullScr IO-Red. Multi 2744 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 2745 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 2746 2747 2748NetBSD Notes: 2749============= 2750 2751Starting at version 0.9.2, U-Boot supports NetBSD both as host 2752(build U-Boot) and target system (boots NetBSD/mpc8xx). 2753 2754Building requires a cross environment; it is known to work on 2755NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 2756need gmake since the Makefiles are not compatible with BSD make). 2757Note that the cross-powerpc package does not install include files; 2758attempting to build U-Boot will fail because <machine/ansi.h> is 2759missing. This file has to be installed and patched manually: 2760 2761 # cd /usr/pkg/cross/powerpc-netbsd/include 2762 # mkdir powerpc 2763 # ln -s powerpc machine 2764 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 2765 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 2766 2767Native builds *don't* work due to incompatibilities between native 2768and U-Boot include files. 2769 2770Booting assumes that (the first part of) the image booted is a 2771stage-2 loader which in turn loads and then invokes the kernel 2772proper. Loader sources will eventually appear in the NetBSD source 2773tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 2774meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for 2775details. 2776 2777 2778Implementation Internals: 2779========================= 2780 2781The following is not intended to be a complete description of every 2782implementation detail. However, it should help to understand the 2783inner workings of U-Boot and make it easier to port it to custom 2784hardware. 2785 2786 2787Initial Stack, Global Data: 2788--------------------------- 2789 2790The implementation of U-Boot is complicated by the fact that U-Boot 2791starts running out of ROM (flash memory), usually without access to 2792system RAM (because the memory controller is not initialized yet). 2793This means that we don't have writable Data or BSS segments, and BSS 2794is not initialized as zero. To be able to get a C environment working 2795at all, we have to allocate at least a minimal stack. Implementation 2796options for this are defined and restricted by the CPU used: Some CPU 2797models provide on-chip memory (like the IMMR area on MPC8xx and 2798MPC826x processors), on others (parts of) the data cache can be 2799locked as (mis-) used as memory, etc. 2800 2801 Chris Hallinan posted a good summary of these issues to the 2802 u-boot-users mailing list: 2803 2804 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 2805 From: "Chris Hallinan" <clh@net1plus.com> 2806 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 2807 ... 2808 2809 Correct me if I'm wrong, folks, but the way I understand it 2810 is this: Using DCACHE as initial RAM for Stack, etc, does not 2811 require any physical RAM backing up the cache. The cleverness 2812 is that the cache is being used as a temporary supply of 2813 necessary storage before the SDRAM controller is setup. It's 2814 beyond the scope of this list to expain the details, but you 2815 can see how this works by studying the cache architecture and 2816 operation in the architecture and processor-specific manuals. 2817 2818 OCM is On Chip Memory, which I believe the 405GP has 4K. It 2819 is another option for the system designer to use as an 2820 initial stack/ram area prior to SDRAM being available. Either 2821 option should work for you. Using CS 4 should be fine if your 2822 board designers haven't used it for something that would 2823 cause you grief during the initial boot! It is frequently not 2824 used. 2825 2826 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 2827 with your processor/board/system design. The default value 2828 you will find in any recent u-boot distribution in 2829 Walnut405.h should work for you. I'd set it to a value larger 2830 than your SDRAM module. If you have a 64MB SDRAM module, set 2831 it above 400_0000. Just make sure your board has no resources 2832 that are supposed to respond to that address! That code in 2833 start.S has been around a while and should work as is when 2834 you get the config right. 2835 2836 -Chris Hallinan 2837 DS4.COM, Inc. 2838 2839It is essential to remember this, since it has some impact on the C 2840code for the initialization procedures: 2841 2842* Initialized global data (data segment) is read-only. Do not attempt 2843 to write it. 2844 2845* Do not use any unitialized global data (or implicitely initialized 2846 as zero data - BSS segment) at all - this is undefined, initiali- 2847 zation is performed later (when relocating to RAM). 2848 2849* Stack space is very limited. Avoid big data buffers or things like 2850 that. 2851 2852Having only the stack as writable memory limits means we cannot use 2853normal global data to share information beween the code. But it 2854turned out that the implementation of U-Boot can be greatly 2855simplified by making a global data structure (gd_t) available to all 2856functions. We could pass a pointer to this data as argument to _all_ 2857functions, but this would bloat the code. Instead we use a feature of 2858the GCC compiler (Global Register Variables) to share the data: we 2859place a pointer (gd) to the global data into a register which we 2860reserve for this purpose. 2861 2862When choosing a register for such a purpose we are restricted by the 2863relevant (E)ABI specifications for the current architecture, and by 2864GCC's implementation. 2865 2866For PowerPC, the following registers have specific use: 2867 R1: stack pointer 2868 R2: TOC pointer 2869 R3-R4: parameter passing and return values 2870 R5-R10: parameter passing 2871 R13: small data area pointer 2872 R30: GOT pointer 2873 R31: frame pointer 2874 2875 (U-Boot also uses R14 as internal GOT pointer.) 2876 2877 ==> U-Boot will use R29 to hold a pointer to the global data 2878 2879 Note: on PPC, we could use a static initializer (since the 2880 address of the global data structure is known at compile time), 2881 but it turned out that reserving a register results in somewhat 2882 smaller code - although the code savings are not that big (on 2883 average for all boards 752 bytes for the whole U-Boot image, 2884 624 text + 127 data). 2885 2886On ARM, the following registers are used: 2887 2888 R0: function argument word/integer result 2889 R1-R3: function argument word 2890 R9: GOT pointer 2891 R10: stack limit (used only if stack checking if enabled) 2892 R11: argument (frame) pointer 2893 R12: temporary workspace 2894 R13: stack pointer 2895 R14: link register 2896 R15: program counter 2897 2898 ==> U-Boot will use R8 to hold a pointer to the global data 2899 2900 2901Memory Management: 2902------------------ 2903 2904U-Boot runs in system state and uses physical addresses, i.e. the 2905MMU is not used either for address mapping nor for memory protection. 2906 2907The available memory is mapped to fixed addresses using the memory 2908controller. In this process, a contiguous block is formed for each 2909memory type (Flash, SDRAM, SRAM), even when it consists of several 2910physical memory banks. 2911 2912U-Boot is installed in the first 128 kB of the first Flash bank (on 2913TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 2914booting and sizing and initializing DRAM, the code relocates itself 2915to the upper end of DRAM. Immediately below the U-Boot code some 2916memory is reserved for use by malloc() [see CFG_MALLOC_LEN 2917configuration setting]. Below that, a structure with global Board 2918Info data is placed, followed by the stack (growing downward). 2919 2920Additionally, some exception handler code is copied to the low 8 kB 2921of DRAM (0x00000000 ... 0x00001FFF). 2922 2923So a typical memory configuration with 16 MB of DRAM could look like 2924this: 2925 2926 0x0000 0000 Exception Vector code 2927 : 2928 0x0000 1FFF 2929 0x0000 2000 Free for Application Use 2930 : 2931 : 2932 2933 : 2934 : 2935 0x00FB FF20 Monitor Stack (Growing downward) 2936 0x00FB FFAC Board Info Data and permanent copy of global data 2937 0x00FC 0000 Malloc Arena 2938 : 2939 0x00FD FFFF 2940 0x00FE 0000 RAM Copy of Monitor Code 2941 ... eventually: LCD or video framebuffer 2942 ... eventually: pRAM (Protected RAM - unchanged by reset) 2943 0x00FF FFFF [End of RAM] 2944 2945 2946System Initialization: 2947---------------------- 2948 2949In the reset configuration, U-Boot starts at the reset entry point 2950(on most PowerPC systens at address 0x00000100). Because of the reset 2951configuration for CS0# this is a mirror of the onboard Flash memory. 2952To be able to re-map memory U-Boot then jumps to its link address. 2953To be able to implement the initialization code in C, a (small!) 2954initial stack is set up in the internal Dual Ported RAM (in case CPUs 2955which provide such a feature like MPC8xx or MPC8260), or in a locked 2956part of the data cache. After that, U-Boot initializes the CPU core, 2957the caches and the SIU. 2958 2959Next, all (potentially) available memory banks are mapped using a 2960preliminary mapping. For example, we put them on 512 MB boundaries 2961(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 2962on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 2963programmed for SDRAM access. Using the temporary configuration, a 2964simple memory test is run that determines the size of the SDRAM 2965banks. 2966 2967When there is more than one SDRAM bank, and the banks are of 2968different size, the largest is mapped first. For equal size, the first 2969bank (CS2#) is mapped first. The first mapping is always for address 29700x00000000, with any additional banks following immediately to create 2971contiguous memory starting from 0. 2972 2973Then, the monitor installs itself at the upper end of the SDRAM area 2974and allocates memory for use by malloc() and for the global Board 2975Info data; also, the exception vector code is copied to the low RAM 2976pages, and the final stack is set up. 2977 2978Only after this relocation will you have a "normal" C environment; 2979until that you are restricted in several ways, mostly because you are 2980running from ROM, and because the code will have to be relocated to a 2981new address in RAM. 2982 2983 2984U-Boot Porting Guide: 2985---------------------- 2986 2987[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 2988list, October 2002] 2989 2990 2991int main (int argc, char *argv[]) 2992{ 2993 sighandler_t no_more_time; 2994 2995 signal (SIGALRM, no_more_time); 2996 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 2997 2998 if (available_money > available_manpower) { 2999 pay consultant to port U-Boot; 3000 return 0; 3001 } 3002 3003 Download latest U-Boot source; 3004 3005 Subscribe to u-boot-users mailing list; 3006 3007 if (clueless) { 3008 email ("Hi, I am new to U-Boot, how do I get started?"); 3009 } 3010 3011 while (learning) { 3012 Read the README file in the top level directory; 3013 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3014 Read the source, Luke; 3015 } 3016 3017 if (available_money > toLocalCurrency ($2500)) { 3018 Buy a BDI2000; 3019 } else { 3020 Add a lot of aggravation and time; 3021 } 3022 3023 Create your own board support subdirectory; 3024 3025 Create your own board config file; 3026 3027 while (!running) { 3028 do { 3029 Add / modify source code; 3030 } until (compiles); 3031 Debug; 3032 if (clueless) 3033 email ("Hi, I am having problems..."); 3034 } 3035 Send patch file to Wolfgang; 3036 3037 return 0; 3038} 3039 3040void no_more_time (int sig) 3041{ 3042 hire_a_guru(); 3043} 3044 3045 3046Coding Standards: 3047----------------- 3048 3049All contributions to U-Boot should conform to the Linux kernel 3050coding style; see the file "Documentation/CodingStyle" in your Linux 3051kernel source directory. 3052 3053Please note that U-Boot is implemented in C (and to some small parts 3054in Assembler); no C++ is used, so please do not use C++ style 3055comments (//) in your code. 3056 3057Please also stick to the following formatting rules: 3058- remove any trailing white space 3059- use TAB characters for indentation, not spaces 3060- make sure NOT to use DOS '\r\n' line feeds 3061- do not add more than 2 empty lines to source files 3062- do not add trailing empty lines to source files 3063 3064Submissions which do not conform to the standards may be returned 3065with a request to reformat the changes. 3066 3067 3068Submitting Patches: 3069------------------- 3070 3071Since the number of patches for U-Boot is growing, we need to 3072establish some rules. Submissions which do not conform to these rules 3073may be rejected, even when they contain important and valuable stuff. 3074 3075 3076When you send a patch, please include the following information with 3077it: 3078 3079* For bug fixes: a description of the bug and how your patch fixes 3080 this bug. Please try to include a way of demonstrating that the 3081 patch actually fixes something. 3082 3083* For new features: a description of the feature and your 3084 implementation. 3085 3086* A CHANGELOG entry as plaintext (separate from the patch) 3087 3088* For major contributions, your entry to the CREDITS file 3089 3090* When you add support for a new board, don't forget to add this 3091 board to the MAKEALL script, too. 3092 3093* If your patch adds new configuration options, don't forget to 3094 document these in the README file. 3095 3096* The patch itself. If you are accessing the CVS repository use "cvs 3097 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your 3098 version of diff does not support these options, then get the latest 3099 version of GNU diff. 3100 3101 The current directory when running this command shall be the top 3102 level directory of the U-Boot source tree, or it's parent directory 3103 (i. e. please make sure that your patch includes sufficient 3104 directory information for the affected files). 3105 3106 We accept patches as plain text, MIME attachments or as uuencoded 3107 gzipped text. 3108 3109* If one logical set of modifications affects or creates several 3110 files, all these changes shall be submitted in a SINGLE patch file. 3111 3112* Changesets that contain different, unrelated modifications shall be 3113 submitted as SEPARATE patches, one patch per changeset. 3114 3115 3116Notes: 3117 3118* Before sending the patch, run the MAKEALL script on your patched 3119 source tree and make sure that no errors or warnings are reported 3120 for any of the boards. 3121 3122* Keep your modifications to the necessary minimum: A patch 3123 containing several unrelated changes or arbitrary reformats will be 3124 returned with a request to re-formatting / split it. 3125 3126* If you modify existing code, make sure that your new code does not 3127 add to the memory footprint of the code ;-) Small is beautiful! 3128 When adding new features, these should compile conditionally only 3129 (using #ifdef), and the resulting code with the new feature 3130 disabled must not need more memory than the old code without your 3131 modification. 3132