1# 2# (C) Copyright 2000 - 2008 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 8# This program is free software; you can redistribute it and/or 9# modify it under the terms of the GNU General Public License as 10# published by the Free Software Foundation; either version 2 of 11# the License, or (at your option) any later version. 12# 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17# 18# You should have received a copy of the GNU General Public License 19# along with this program; if not, write to the Free Software 20# Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-Boot you should send a message to the U-Boot mailing list at 63<u-boot-users@lists.sourceforge.net>. There is also an archive of 64previous traffic on the mailing list - please search the archive 65before asking FAQ's. Please see 66http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Official releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-built (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 88- start from 8xxrom sources 89- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 90- clean up code 91- make it easier to add custom boards 92- make it possible to add other [PowerPC] CPUs 93- extend functions, especially: 94 * Provide extended interface to Linux boot loader 95 * S-Record download 96 * network boot 97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 98- create ARMBoot project (http://sourceforge.net/projects/armboot) 99- add other CPU families (starting with ARM) 100- create U-Boot project (http://sourceforge.net/projects/u-boot) 101- current project page: see http://www.denx.de/wiki/U-Boot 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129U-Boot uses a 3 level version number containing a version, a 130sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 131sub-version "34", and patchlevel "4". 132 133The patchlevel is used to indicate certain stages of development 134between released versions, i. e. officially released versions of 135U-Boot will always have a patchlevel of "0". 136 137 138Directory Hierarchy: 139==================== 140 141- board Board dependent files 142- common Misc architecture independent functions 143- cpu CPU specific files 144 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 145 - arm720t Files specific to ARM 720 CPUs 146 - arm920t Files specific to ARM 920 CPUs 147 - at91rm9200 Files specific to Atmel AT91RM9200 CPU 148 - imx Files specific to Freescale MC9328 i.MX CPUs 149 - s3c24x0 Files specific to Samsung S3C24X0 CPUs 150 - arm925t Files specific to ARM 925 CPUs 151 - arm926ejs Files specific to ARM 926 CPUs 152 - arm1136 Files specific to ARM 1136 CPUs 153 - at32ap Files specific to Atmel AVR32 AP CPUs 154 - i386 Files specific to i386 CPUs 155 - ixp Files specific to Intel XScale IXP CPUs 156 - leon2 Files specific to Gaisler LEON2 SPARC CPU 157 - leon3 Files specific to Gaisler LEON3 SPARC CPU 158 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 159 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 160 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 161 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 162 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 163 - mips Files specific to MIPS CPUs 164 - mpc5xx Files specific to Freescale MPC5xx CPUs 165 - mpc5xxx Files specific to Freescale MPC5xxx CPUs 166 - mpc8xx Files specific to Freescale MPC8xx CPUs 167 - mpc8220 Files specific to Freescale MPC8220 CPUs 168 - mpc824x Files specific to Freescale MPC824x CPUs 169 - mpc8260 Files specific to Freescale MPC8260 CPUs 170 - mpc85xx Files specific to Freescale MPC85xx CPUs 171 - nios Files specific to Altera NIOS CPUs 172 - nios2 Files specific to Altera Nios-II CPUs 173 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs 174 - pxa Files specific to Intel XScale PXA CPUs 175 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 176 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 177- disk Code for disk drive partition handling 178- doc Documentation (don't expect too much) 179- drivers Commonly used device drivers 180- dtt Digital Thermometer and Thermostat drivers 181- examples Example code for standalone applications, etc. 182- include Header Files 183- lib_arm Files generic to ARM architecture 184- lib_avr32 Files generic to AVR32 architecture 185- lib_generic Files generic to all architectures 186- lib_i386 Files generic to i386 architecture 187- lib_m68k Files generic to m68k architecture 188- lib_mips Files generic to MIPS architecture 189- lib_nios Files generic to NIOS architecture 190- lib_ppc Files generic to PowerPC architecture 191- lib_sparc Files generic to SPARC architecture 192- libfdt Library files to support flattened device trees 193- net Networking code 194- post Power On Self Test 195- rtc Real Time Clock drivers 196- tools Tools to build S-Record or U-Boot images, etc. 197 198Software Configuration: 199======================= 200 201Configuration is usually done using C preprocessor defines; the 202rationale behind that is to avoid dead code whenever possible. 203 204There are two classes of configuration variables: 205 206* Configuration _OPTIONS_: 207 These are selectable by the user and have names beginning with 208 "CONFIG_". 209 210* Configuration _SETTINGS_: 211 These depend on the hardware etc. and should not be meddled with if 212 you don't know what you're doing; they have names beginning with 213 "CFG_". 214 215Later we will add a configuration tool - probably similar to or even 216identical to what's used for the Linux kernel. Right now, we have to 217do the configuration by hand, which means creating some symbolic 218links and editing some configuration files. We use the TQM8xxL boards 219as an example here. 220 221 222Selection of Processor Architecture and Board Type: 223--------------------------------------------------- 224 225For all supported boards there are ready-to-use default 226configurations available; just type "make <board_name>_config". 227 228Example: For a TQM823L module type: 229 230 cd u-boot 231 make TQM823L_config 232 233For the Cogent platform, you need to specify the CPU type as well; 234e.g. "make cogent_mpc8xx_config". And also configure the cogent 235directory according to the instructions in cogent/README. 236 237 238Configuration Options: 239---------------------- 240 241Configuration depends on the combination of board and CPU type; all 242such information is kept in a configuration file 243"include/configs/<board_name>.h". 244 245Example: For a TQM823L module, all configuration settings are in 246"include/configs/TQM823L.h". 247 248 249Many of the options are named exactly as the corresponding Linux 250kernel configuration options. The intention is to make it easier to 251build a config tool - later. 252 253 254The following options need to be configured: 255 256- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 257 258- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 259 260- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 261 Define exactly one, e.g. CONFIG_ATSTK1002 262 263- CPU Module Type: (if CONFIG_COGENT is defined) 264 Define exactly one of 265 CONFIG_CMA286_60_OLD 266--- FIXME --- not tested yet: 267 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 268 CONFIG_CMA287_23, CONFIG_CMA287_50 269 270- Motherboard Type: (if CONFIG_COGENT is defined) 271 Define exactly one of 272 CONFIG_CMA101, CONFIG_CMA102 273 274- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 275 Define one or more of 276 CONFIG_CMA302 277 278- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 279 Define one or more of 280 CONFIG_LCD_HEARTBEAT - update a character position on 281 the LCD display every second with 282 a "rotator" |\-/|\-/ 283 284- Board flavour: (if CONFIG_MPC8260ADS is defined) 285 CONFIG_ADSTYPE 286 Possible values are: 287 CFG_8260ADS - original MPC8260ADS 288 CFG_8266ADS - MPC8266ADS 289 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 290 CFG_8272ADS - MPC8272ADS 291 292- MPC824X Family Member (if CONFIG_MPC824X is defined) 293 Define exactly one of 294 CONFIG_MPC8240, CONFIG_MPC8245 295 296- 8xx CPU Options: (if using an MPC8xx CPU) 297 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 298 get_gclk_freq() cannot work 299 e.g. if there is no 32KHz 300 reference PIT/RTC clock 301 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 302 or XTAL/EXTAL) 303 304- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 305 CFG_8xx_CPUCLK_MIN 306 CFG_8xx_CPUCLK_MAX 307 CONFIG_8xx_CPUCLK_DEFAULT 308 See doc/README.MPC866 309 310 CFG_MEASURE_CPUCLK 311 312 Define this to measure the actual CPU clock instead 313 of relying on the correctness of the configured 314 values. Mostly useful for board bringup to make sure 315 the PLL is locked at the intended frequency. Note 316 that this requires a (stable) reference clock (32 kHz 317 RTC clock or CFG_8XX_XIN) 318 319- Intel Monahans options: 320 CFG_MONAHANS_RUN_MODE_OSC_RATIO 321 322 Defines the Monahans run mode to oscillator 323 ratio. Valid values are 8, 16, 24, 31. The core 324 frequency is this value multiplied by 13 MHz. 325 326 CFG_MONAHANS_TURBO_RUN_MODE_RATIO 327 328 Defines the Monahans turbo mode to oscillator 329 ratio. Valid values are 1 (default if undefined) and 330 2. The core frequency as calculated above is multiplied 331 by this value. 332 333- Linux Kernel Interface: 334 CONFIG_CLOCKS_IN_MHZ 335 336 U-Boot stores all clock information in Hz 337 internally. For binary compatibility with older Linux 338 kernels (which expect the clocks passed in the 339 bd_info data to be in MHz) the environment variable 340 "clocks_in_mhz" can be defined so that U-Boot 341 converts clock data to MHZ before passing it to the 342 Linux kernel. 343 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 344 "clocks_in_mhz=1" is automatically included in the 345 default environment. 346 347 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 348 349 When transferring memsize parameter to linux, some versions 350 expect it to be in bytes, others in MB. 351 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 352 353 CONFIG_OF_LIBFDT 354 355 New kernel versions are expecting firmware settings to be 356 passed using flattened device trees (based on open firmware 357 concepts). 358 359 CONFIG_OF_LIBFDT 360 * New libfdt-based support 361 * Adds the "fdt" command 362 * The bootm command automatically updates the fdt 363 364 OF_CPU - The proper name of the cpus node. 365 OF_SOC - The proper name of the soc node. 366 OF_TBCLK - The timebase frequency. 367 OF_STDOUT_PATH - The path to the console device 368 369 boards with QUICC Engines require OF_QE to set UCC MAC 370 addresses 371 372 CONFIG_OF_BOARD_SETUP 373 374 Board code has addition modification that it wants to make 375 to the flat device tree before handing it off to the kernel 376 377 CONFIG_OF_BOOT_CPU 378 379 This define fills in the correct boot CPU in the boot 380 param header, the default value is zero if undefined. 381 382- Serial Ports: 383 CONFIG_PL010_SERIAL 384 385 Define this if you want support for Amba PrimeCell PL010 UARTs. 386 387 CONFIG_PL011_SERIAL 388 389 Define this if you want support for Amba PrimeCell PL011 UARTs. 390 391 CONFIG_PL011_CLOCK 392 393 If you have Amba PrimeCell PL011 UARTs, set this variable to 394 the clock speed of the UARTs. 395 396 CONFIG_PL01x_PORTS 397 398 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 399 define this to a list of base addresses for each (supported) 400 port. See e.g. include/configs/versatile.h 401 402 403- Console Interface: 404 Depending on board, define exactly one serial port 405 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 406 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 407 console by defining CONFIG_8xx_CONS_NONE 408 409 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 410 port routines must be defined elsewhere 411 (i.e. serial_init(), serial_getc(), ...) 412 413 CONFIG_CFB_CONSOLE 414 Enables console device for a color framebuffer. Needs following 415 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 416 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 417 (default big endian) 418 VIDEO_HW_RECTFILL graphic chip supports 419 rectangle fill 420 (cf. smiLynxEM) 421 VIDEO_HW_BITBLT graphic chip supports 422 bit-blit (cf. smiLynxEM) 423 VIDEO_VISIBLE_COLS visible pixel columns 424 (cols=pitch) 425 VIDEO_VISIBLE_ROWS visible pixel rows 426 VIDEO_PIXEL_SIZE bytes per pixel 427 VIDEO_DATA_FORMAT graphic data format 428 (0-5, cf. cfb_console.c) 429 VIDEO_FB_ADRS framebuffer address 430 VIDEO_KBD_INIT_FCT keyboard int fct 431 (i.e. i8042_kbd_init()) 432 VIDEO_TSTC_FCT test char fct 433 (i.e. i8042_tstc) 434 VIDEO_GETC_FCT get char fct 435 (i.e. i8042_getc) 436 CONFIG_CONSOLE_CURSOR cursor drawing on/off 437 (requires blink timer 438 cf. i8042.c) 439 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 440 CONFIG_CONSOLE_TIME display time/date info in 441 upper right corner 442 (requires CONFIG_CMD_DATE) 443 CONFIG_VIDEO_LOGO display Linux logo in 444 upper left corner 445 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 446 linux_logo.h for logo. 447 Requires CONFIG_VIDEO_LOGO 448 CONFIG_CONSOLE_EXTRA_INFO 449 additional board info beside 450 the logo 451 452 When CONFIG_CFB_CONSOLE is defined, video console is 453 default i/o. Serial console can be forced with 454 environment 'console=serial'. 455 456 When CONFIG_SILENT_CONSOLE is defined, all console 457 messages (by U-Boot and Linux!) can be silenced with 458 the "silent" environment variable. See 459 doc/README.silent for more information. 460 461- Console Baudrate: 462 CONFIG_BAUDRATE - in bps 463 Select one of the baudrates listed in 464 CFG_BAUDRATE_TABLE, see below. 465 CFG_BRGCLK_PRESCALE, baudrate prescale 466 467- Interrupt driven serial port input: 468 CONFIG_SERIAL_SOFTWARE_FIFO 469 470 PPC405GP only. 471 Use an interrupt handler for receiving data on the 472 serial port. It also enables using hardware handshake 473 (RTS/CTS) and UART's built-in FIFO. Set the number of 474 bytes the interrupt driven input buffer should have. 475 476 Leave undefined to disable this feature, including 477 disable the buffer and hardware handshake. 478 479- Console UART Number: 480 CONFIG_UART1_CONSOLE 481 482 AMCC PPC4xx only. 483 If defined internal UART1 (and not UART0) is used 484 as default U-Boot console. 485 486- Boot Delay: CONFIG_BOOTDELAY - in seconds 487 Delay before automatically booting the default image; 488 set to -1 to disable autoboot. 489 490 See doc/README.autoboot for these options that 491 work with CONFIG_BOOTDELAY. None are required. 492 CONFIG_BOOT_RETRY_TIME 493 CONFIG_BOOT_RETRY_MIN 494 CONFIG_AUTOBOOT_KEYED 495 CONFIG_AUTOBOOT_PROMPT 496 CONFIG_AUTOBOOT_DELAY_STR 497 CONFIG_AUTOBOOT_STOP_STR 498 CONFIG_AUTOBOOT_DELAY_STR2 499 CONFIG_AUTOBOOT_STOP_STR2 500 CONFIG_ZERO_BOOTDELAY_CHECK 501 CONFIG_RESET_TO_RETRY 502 503- Autoboot Command: 504 CONFIG_BOOTCOMMAND 505 Only needed when CONFIG_BOOTDELAY is enabled; 506 define a command string that is automatically executed 507 when no character is read on the console interface 508 within "Boot Delay" after reset. 509 510 CONFIG_BOOTARGS 511 This can be used to pass arguments to the bootm 512 command. The value of CONFIG_BOOTARGS goes into the 513 environment value "bootargs". 514 515 CONFIG_RAMBOOT and CONFIG_NFSBOOT 516 The value of these goes into the environment as 517 "ramboot" and "nfsboot" respectively, and can be used 518 as a convenience, when switching between booting from 519 RAM and NFS. 520 521- Pre-Boot Commands: 522 CONFIG_PREBOOT 523 524 When this option is #defined, the existence of the 525 environment variable "preboot" will be checked 526 immediately before starting the CONFIG_BOOTDELAY 527 countdown and/or running the auto-boot command resp. 528 entering interactive mode. 529 530 This feature is especially useful when "preboot" is 531 automatically generated or modified. For an example 532 see the LWMON board specific code: here "preboot" is 533 modified when the user holds down a certain 534 combination of keys on the (special) keyboard when 535 booting the systems 536 537- Serial Download Echo Mode: 538 CONFIG_LOADS_ECHO 539 If defined to 1, all characters received during a 540 serial download (using the "loads" command) are 541 echoed back. This might be needed by some terminal 542 emulations (like "cu"), but may as well just take 543 time on others. This setting #define's the initial 544 value of the "loads_echo" environment variable. 545 546- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 547 CONFIG_KGDB_BAUDRATE 548 Select one of the baudrates listed in 549 CFG_BAUDRATE_TABLE, see below. 550 551- Monitor Functions: 552 Monitor commands can be included or excluded 553 from the build by using the #include files 554 "config_cmd_all.h" and #undef'ing unwanted 555 commands, or using "config_cmd_default.h" 556 and augmenting with additional #define's 557 for wanted commands. 558 559 The default command configuration includes all commands 560 except those marked below with a "*". 561 562 CONFIG_CMD_ASKENV * ask for env variable 563 CONFIG_CMD_AUTOSCRIPT Autoscript Support 564 CONFIG_CMD_BDI bdinfo 565 CONFIG_CMD_BEDBUG * Include BedBug Debugger 566 CONFIG_CMD_BMP * BMP support 567 CONFIG_CMD_BSP * Board specific commands 568 CONFIG_CMD_BOOTD bootd 569 CONFIG_CMD_CACHE * icache, dcache 570 CONFIG_CMD_CONSOLE coninfo 571 CONFIG_CMD_DATE * support for RTC, date/time... 572 CONFIG_CMD_DHCP * DHCP support 573 CONFIG_CMD_DIAG * Diagnostics 574 CONFIG_CMD_DOC * Disk-On-Chip Support 575 CONFIG_CMD_DTT * Digital Therm and Thermostat 576 CONFIG_CMD_ECHO echo arguments 577 CONFIG_CMD_EEPROM * EEPROM read/write support 578 CONFIG_CMD_ELF * bootelf, bootvx 579 CONFIG_CMD_ENV saveenv 580 CONFIG_CMD_FDC * Floppy Disk Support 581 CONFIG_CMD_FAT * FAT partition support 582 CONFIG_CMD_FDOS * Dos diskette Support 583 CONFIG_CMD_FLASH flinfo, erase, protect 584 CONFIG_CMD_FPGA FPGA device initialization support 585 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 586 CONFIG_CMD_I2C * I2C serial bus support 587 CONFIG_CMD_IDE * IDE harddisk support 588 CONFIG_CMD_IMI iminfo 589 CONFIG_CMD_IMLS List all found images 590 CONFIG_CMD_IMMAP * IMMR dump support 591 CONFIG_CMD_IRQ * irqinfo 592 CONFIG_CMD_ITEST Integer/string test of 2 values 593 CONFIG_CMD_JFFS2 * JFFS2 Support 594 CONFIG_CMD_KGDB * kgdb 595 CONFIG_CMD_LOADB loadb 596 CONFIG_CMD_LOADS loads 597 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 598 loop, loopw, mtest 599 CONFIG_CMD_MISC Misc functions like sleep etc 600 CONFIG_CMD_MMC * MMC memory mapped support 601 CONFIG_CMD_MII * MII utility commands 602 CONFIG_CMD_NAND * NAND support 603 CONFIG_CMD_NET bootp, tftpboot, rarpboot 604 CONFIG_CMD_PCI * pciinfo 605 CONFIG_CMD_PCMCIA * PCMCIA support 606 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 607 host 608 CONFIG_CMD_PORTIO * Port I/O 609 CONFIG_CMD_REGINFO * Register dump 610 CONFIG_CMD_RUN run command in env variable 611 CONFIG_CMD_SAVES * save S record dump 612 CONFIG_CMD_SCSI * SCSI Support 613 CONFIG_CMD_SDRAM * print SDRAM configuration information 614 (requires CONFIG_CMD_I2C) 615 CONFIG_CMD_SETGETDCR Support for DCR Register access 616 (4xx only) 617 CONFIG_CMD_SPI * SPI serial bus support 618 CONFIG_CMD_USB * USB support 619 CONFIG_CMD_VFD * VFD support (TRAB) 620 CONFIG_CMD_CDP * Cisco Discover Protocol support 621 CONFIG_CMD_FSL * Microblaze FSL support 622 623 624 EXAMPLE: If you want all functions except of network 625 support you can write: 626 627 #include "config_cmd_all.h" 628 #undef CONFIG_CMD_NET 629 630 Other Commands: 631 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 632 633 Note: Don't enable the "icache" and "dcache" commands 634 (configuration option CONFIG_CMD_CACHE) unless you know 635 what you (and your U-Boot users) are doing. Data 636 cache cannot be enabled on systems like the 8xx or 637 8260 (where accesses to the IMMR region must be 638 uncached), and it cannot be disabled on all other 639 systems where we (mis-) use the data cache to hold an 640 initial stack and some data. 641 642 643 XXX - this list needs to get updated! 644 645- Watchdog: 646 CONFIG_WATCHDOG 647 If this variable is defined, it enables watchdog 648 support. There must be support in the platform specific 649 code for a watchdog. For the 8xx and 8260 CPUs, the 650 SIU Watchdog feature is enabled in the SYPCR 651 register. 652 653- U-Boot Version: 654 CONFIG_VERSION_VARIABLE 655 If this variable is defined, an environment variable 656 named "ver" is created by U-Boot showing the U-Boot 657 version as printed by the "version" command. 658 This variable is readonly. 659 660- Real-Time Clock: 661 662 When CONFIG_CMD_DATE is selected, the type of the RTC 663 has to be selected, too. Define exactly one of the 664 following options: 665 666 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 667 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 668 CONFIG_RTC_MC13783 - use MC13783 RTC 669 CONFIG_RTC_MC146818 - use MC146818 RTC 670 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 671 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 672 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 673 CONFIG_RTC_DS164x - use Dallas DS164x RTC 674 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 675 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 676 CFG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 677 678 Note that if the RTC uses I2C, then the I2C interface 679 must also be configured. See I2C Support, below. 680 681- Timestamp Support: 682 683 When CONFIG_TIMESTAMP is selected, the timestamp 684 (date and time) of an image is printed by image 685 commands like bootm or iminfo. This option is 686 automatically enabled when you select CONFIG_CMD_DATE . 687 688- Partition Support: 689 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 690 and/or CONFIG_ISO_PARTITION 691 692 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 693 CONFIG_CMD_SCSI) you must configure support for at 694 least one partition type as well. 695 696- IDE Reset method: 697 CONFIG_IDE_RESET_ROUTINE - this is defined in several 698 board configurations files but used nowhere! 699 700 CONFIG_IDE_RESET - is this is defined, IDE Reset will 701 be performed by calling the function 702 ide_set_reset(int reset) 703 which has to be defined in a board specific file 704 705- ATAPI Support: 706 CONFIG_ATAPI 707 708 Set this to enable ATAPI support. 709 710- LBA48 Support 711 CONFIG_LBA48 712 713 Set this to enable support for disks larger than 137GB 714 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 715 Whithout these , LBA48 support uses 32bit variables and will 'only' 716 support disks up to 2.1TB. 717 718 CFG_64BIT_LBA: 719 When enabled, makes the IDE subsystem use 64bit sector addresses. 720 Default is 32bit. 721 722- SCSI Support: 723 At the moment only there is only support for the 724 SYM53C8XX SCSI controller; define 725 CONFIG_SCSI_SYM53C8XX to enable it. 726 727 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 728 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 729 CFG_SCSI_MAX_LUN] can be adjusted to define the 730 maximum numbers of LUNs, SCSI ID's and target 731 devices. 732 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 733 734- NETWORK Support (PCI): 735 CONFIG_E1000 736 Support for Intel 8254x gigabit chips. 737 738 CONFIG_E1000_FALLBACK_MAC 739 default MAC for empty EEPROM after production. 740 741 CONFIG_EEPRO100 742 Support for Intel 82557/82559/82559ER chips. 743 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 744 write routine for first time initialisation. 745 746 CONFIG_TULIP 747 Support for Digital 2114x chips. 748 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 749 modem chip initialisation (KS8761/QS6611). 750 751 CONFIG_NATSEMI 752 Support for National dp83815 chips. 753 754 CONFIG_NS8382X 755 Support for National dp8382[01] gigabit chips. 756 757- NETWORK Support (other): 758 759 CONFIG_DRIVER_LAN91C96 760 Support for SMSC's LAN91C96 chips. 761 762 CONFIG_LAN91C96_BASE 763 Define this to hold the physical address 764 of the LAN91C96's I/O space 765 766 CONFIG_LAN91C96_USE_32_BIT 767 Define this to enable 32 bit addressing 768 769 CONFIG_DRIVER_SMC91111 770 Support for SMSC's LAN91C111 chip 771 772 CONFIG_SMC91111_BASE 773 Define this to hold the physical address 774 of the device (I/O space) 775 776 CONFIG_SMC_USE_32_BIT 777 Define this if data bus is 32 bits 778 779 CONFIG_SMC_USE_IOFUNCS 780 Define this to use i/o functions instead of macros 781 (some hardware wont work with macros) 782 783 CONFIG_DRIVER_SMC911X 784 Support for SMSC's LAN911x and LAN921x chips 785 786 CONFIG_DRIVER_SMC911X_BASE 787 Define this to hold the physical address 788 of the device (I/O space) 789 790 CONFIG_DRIVER_SMC911X_32_BIT 791 Define this if data bus is 32 bits 792 793 CONFIG_DRIVER_SMC911X_16_BIT 794 Define this if data bus is 16 bits. If your processor 795 automatically converts one 32 bit word to two 16 bit 796 words you may also try CONFIG_DRIVER_SMC911X_32_BIT. 797 798- USB Support: 799 At the moment only the UHCI host controller is 800 supported (PIP405, MIP405, MPC5200); define 801 CONFIG_USB_UHCI to enable it. 802 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 803 and define CONFIG_USB_STORAGE to enable the USB 804 storage devices. 805 Note: 806 Supported are USB Keyboards and USB Floppy drives 807 (TEAC FD-05PUB). 808 MPC5200 USB requires additional defines: 809 CONFIG_USB_CLOCK 810 for 528 MHz Clock: 0x0001bbbb 811 CONFIG_USB_CONFIG 812 for differential drivers: 0x00001000 813 for single ended drivers: 0x00005000 814 CFG_USB_EVENT_POLL 815 May be defined to allow interrupt polling 816 instead of using asynchronous interrupts 817 818- USB Device: 819 Define the below if you wish to use the USB console. 820 Once firmware is rebuilt from a serial console issue the 821 command "setenv stdin usbtty; setenv stdout usbtty" and 822 attach your USB cable. The Unix command "dmesg" should print 823 it has found a new device. The environment variable usbtty 824 can be set to gserial or cdc_acm to enable your device to 825 appear to a USB host as a Linux gserial device or a 826 Common Device Class Abstract Control Model serial device. 827 If you select usbtty = gserial you should be able to enumerate 828 a Linux host by 829 # modprobe usbserial vendor=0xVendorID product=0xProductID 830 else if using cdc_acm, simply setting the environment 831 variable usbtty to be cdc_acm should suffice. The following 832 might be defined in YourBoardName.h 833 834 CONFIG_USB_DEVICE 835 Define this to build a UDC device 836 837 CONFIG_USB_TTY 838 Define this to have a tty type of device available to 839 talk to the UDC device 840 841 CFG_CONSOLE_IS_IN_ENV 842 Define this if you want stdin, stdout &/or stderr to 843 be set to usbtty. 844 845 mpc8xx: 846 CFG_USB_EXTC_CLK 0xBLAH 847 Derive USB clock from external clock "blah" 848 - CFG_USB_EXTC_CLK 0x02 849 850 CFG_USB_BRG_CLK 0xBLAH 851 Derive USB clock from brgclk 852 - CFG_USB_BRG_CLK 0x04 853 854 If you have a USB-IF assigned VendorID then you may wish to 855 define your own vendor specific values either in BoardName.h 856 or directly in usbd_vendor_info.h. If you don't define 857 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 858 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 859 should pretend to be a Linux device to it's target host. 860 861 CONFIG_USBD_MANUFACTURER 862 Define this string as the name of your company for 863 - CONFIG_USBD_MANUFACTURER "my company" 864 865 CONFIG_USBD_PRODUCT_NAME 866 Define this string as the name of your product 867 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 868 869 CONFIG_USBD_VENDORID 870 Define this as your assigned Vendor ID from the USB 871 Implementors Forum. This *must* be a genuine Vendor ID 872 to avoid polluting the USB namespace. 873 - CONFIG_USBD_VENDORID 0xFFFF 874 875 CONFIG_USBD_PRODUCTID 876 Define this as the unique Product ID 877 for your device 878 - CONFIG_USBD_PRODUCTID 0xFFFF 879 880 881- MMC Support: 882 The MMC controller on the Intel PXA is supported. To 883 enable this define CONFIG_MMC. The MMC can be 884 accessed from the boot prompt by mapping the device 885 to physical memory similar to flash. Command line is 886 enabled with CONFIG_CMD_MMC. The MMC driver also works with 887 the FAT fs. This is enabled with CONFIG_CMD_FAT. 888 889- Journaling Flash filesystem support: 890 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 891 CONFIG_JFFS2_NAND_DEV 892 Define these for a default partition on a NAND device 893 894 CFG_JFFS2_FIRST_SECTOR, 895 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 896 Define these for a default partition on a NOR device 897 898 CFG_JFFS_CUSTOM_PART 899 Define this to create an own partition. You have to provide a 900 function struct part_info* jffs2_part_info(int part_num) 901 902 If you define only one JFFS2 partition you may also want to 903 #define CFG_JFFS_SINGLE_PART 1 904 to disable the command chpart. This is the default when you 905 have not defined a custom partition 906 907- Keyboard Support: 908 CONFIG_ISA_KEYBOARD 909 910 Define this to enable standard (PC-Style) keyboard 911 support 912 913 CONFIG_I8042_KBD 914 Standard PC keyboard driver with US (is default) and 915 GERMAN key layout (switch via environment 'keymap=de') support. 916 Export function i8042_kbd_init, i8042_tstc and i8042_getc 917 for cfb_console. Supports cursor blinking. 918 919- Video support: 920 CONFIG_VIDEO 921 922 Define this to enable video support (for output to 923 video). 924 925 CONFIG_VIDEO_CT69000 926 927 Enable Chips & Technologies 69000 Video chip 928 929 CONFIG_VIDEO_SMI_LYNXEM 930 Enable Silicon Motion SMI 712/710/810 Video chip. The 931 video output is selected via environment 'videoout' 932 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 933 assumed. 934 935 For the CT69000 and SMI_LYNXEM drivers, videomode is 936 selected via environment 'videomode'. Two different ways 937 are possible: 938 - "videomode=num" 'num' is a standard LiLo mode numbers. 939 Following standard modes are supported (* is default): 940 941 Colors 640x480 800x600 1024x768 1152x864 1280x1024 942 -------------+--------------------------------------------- 943 8 bits | 0x301* 0x303 0x305 0x161 0x307 944 15 bits | 0x310 0x313 0x316 0x162 0x319 945 16 bits | 0x311 0x314 0x317 0x163 0x31A 946 24 bits | 0x312 0x315 0x318 ? 0x31B 947 -------------+--------------------------------------------- 948 (i.e. setenv videomode 317; saveenv; reset;) 949 950 - "videomode=bootargs" all the video parameters are parsed 951 from the bootargs. (See drivers/video/videomodes.c) 952 953 954 CONFIG_VIDEO_SED13806 955 Enable Epson SED13806 driver. This driver supports 8bpp 956 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 957 or CONFIG_VIDEO_SED13806_16BPP 958 959- Keyboard Support: 960 CONFIG_KEYBOARD 961 962 Define this to enable a custom keyboard support. 963 This simply calls drv_keyboard_init() which must be 964 defined in your board-specific files. 965 The only board using this so far is RBC823. 966 967- LCD Support: CONFIG_LCD 968 969 Define this to enable LCD support (for output to LCD 970 display); also select one of the supported displays 971 by defining one of these: 972 973 CONFIG_ATMEL_LCD: 974 975 HITACHI TX09D70VM1CCA, 3.5", 240x320. 976 977 CONFIG_NEC_NL6448AC33: 978 979 NEC NL6448AC33-18. Active, color, single scan. 980 981 CONFIG_NEC_NL6448BC20 982 983 NEC NL6448BC20-08. 6.5", 640x480. 984 Active, color, single scan. 985 986 CONFIG_NEC_NL6448BC33_54 987 988 NEC NL6448BC33-54. 10.4", 640x480. 989 Active, color, single scan. 990 991 CONFIG_SHARP_16x9 992 993 Sharp 320x240. Active, color, single scan. 994 It isn't 16x9, and I am not sure what it is. 995 996 CONFIG_SHARP_LQ64D341 997 998 Sharp LQ64D341 display, 640x480. 999 Active, color, single scan. 1000 1001 CONFIG_HLD1045 1002 1003 HLD1045 display, 640x480. 1004 Active, color, single scan. 1005 1006 CONFIG_OPTREX_BW 1007 1008 Optrex CBL50840-2 NF-FW 99 22 M5 1009 or 1010 Hitachi LMG6912RPFC-00T 1011 or 1012 Hitachi SP14Q002 1013 1014 320x240. Black & white. 1015 1016 Normally display is black on white background; define 1017 CFG_WHITE_ON_BLACK to get it inverted. 1018 1019- Splash Screen Support: CONFIG_SPLASH_SCREEN 1020 1021 If this option is set, the environment is checked for 1022 a variable "splashimage". If found, the usual display 1023 of logo, copyright and system information on the LCD 1024 is suppressed and the BMP image at the address 1025 specified in "splashimage" is loaded instead. The 1026 console is redirected to the "nulldev", too. This 1027 allows for a "silent" boot where a splash screen is 1028 loaded very quickly after power-on. 1029 1030- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1031 1032 If this option is set, additionally to standard BMP 1033 images, gzipped BMP images can be displayed via the 1034 splashscreen support or the bmp command. 1035 1036- Compression support: 1037 CONFIG_BZIP2 1038 1039 If this option is set, support for bzip2 compressed 1040 images is included. If not, only uncompressed and gzip 1041 compressed images are supported. 1042 1043 NOTE: the bzip2 algorithm requires a lot of RAM, so 1044 the malloc area (as defined by CFG_MALLOC_LEN) should 1045 be at least 4MB. 1046 1047- MII/PHY support: 1048 CONFIG_PHY_ADDR 1049 1050 The address of PHY on MII bus. 1051 1052 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1053 1054 The clock frequency of the MII bus 1055 1056 CONFIG_PHY_GIGE 1057 1058 If this option is set, support for speed/duplex 1059 detection of gigabit PHY is included. 1060 1061 CONFIG_PHY_RESET_DELAY 1062 1063 Some PHY like Intel LXT971A need extra delay after 1064 reset before any MII register access is possible. 1065 For such PHY, set this option to the usec delay 1066 required. (minimum 300usec for LXT971A) 1067 1068 CONFIG_PHY_CMD_DELAY (ppc4xx) 1069 1070 Some PHY like Intel LXT971A need extra delay after 1071 command issued before MII status register can be read 1072 1073- Ethernet address: 1074 CONFIG_ETHADDR 1075 CONFIG_ETH2ADDR 1076 CONFIG_ETH3ADDR 1077 1078 Define a default value for Ethernet address to use 1079 for the respective Ethernet interface, in case this 1080 is not determined automatically. 1081 1082- IP address: 1083 CONFIG_IPADDR 1084 1085 Define a default value for the IP address to use for 1086 the default Ethernet interface, in case this is not 1087 determined through e.g. bootp. 1088 1089- Server IP address: 1090 CONFIG_SERVERIP 1091 1092 Defines a default value for the IP address of a TFTP 1093 server to contact when using the "tftboot" command. 1094 1095- Multicast TFTP Mode: 1096 CONFIG_MCAST_TFTP 1097 1098 Defines whether you want to support multicast TFTP as per 1099 rfc-2090; for example to work with atftp. Lets lots of targets 1100 tftp down the same boot image concurrently. Note: the Ethernet 1101 driver in use must provide a function: mcast() to join/leave a 1102 multicast group. 1103 1104 CONFIG_BOOTP_RANDOM_DELAY 1105- BOOTP Recovery Mode: 1106 CONFIG_BOOTP_RANDOM_DELAY 1107 1108 If you have many targets in a network that try to 1109 boot using BOOTP, you may want to avoid that all 1110 systems send out BOOTP requests at precisely the same 1111 moment (which would happen for instance at recovery 1112 from a power failure, when all systems will try to 1113 boot, thus flooding the BOOTP server. Defining 1114 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1115 inserted before sending out BOOTP requests. The 1116 following delays are inserted then: 1117 1118 1st BOOTP request: delay 0 ... 1 sec 1119 2nd BOOTP request: delay 0 ... 2 sec 1120 3rd BOOTP request: delay 0 ... 4 sec 1121 4th and following 1122 BOOTP requests: delay 0 ... 8 sec 1123 1124- DHCP Advanced Options: 1125 You can fine tune the DHCP functionality by defining 1126 CONFIG_BOOTP_* symbols: 1127 1128 CONFIG_BOOTP_SUBNETMASK 1129 CONFIG_BOOTP_GATEWAY 1130 CONFIG_BOOTP_HOSTNAME 1131 CONFIG_BOOTP_NISDOMAIN 1132 CONFIG_BOOTP_BOOTPATH 1133 CONFIG_BOOTP_BOOTFILESIZE 1134 CONFIG_BOOTP_DNS 1135 CONFIG_BOOTP_DNS2 1136 CONFIG_BOOTP_SEND_HOSTNAME 1137 CONFIG_BOOTP_NTPSERVER 1138 CONFIG_BOOTP_TIMEOFFSET 1139 CONFIG_BOOTP_VENDOREX 1140 1141 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1142 environment variable, not the BOOTP server. 1143 1144 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1145 serverip from a DHCP server, it is possible that more 1146 than one DNS serverip is offered to the client. 1147 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1148 serverip will be stored in the additional environment 1149 variable "dnsip2". The first DNS serverip is always 1150 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1151 is defined. 1152 1153 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1154 to do a dynamic update of a DNS server. To do this, they 1155 need the hostname of the DHCP requester. 1156 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1157 of the "hostname" environment variable is passed as 1158 option 12 to the DHCP server. 1159 1160 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1161 1162 A 32bit value in microseconds for a delay between 1163 receiving a "DHCP Offer" and sending the "DHCP Request". 1164 This fixes a problem with certain DHCP servers that don't 1165 respond 100% of the time to a "DHCP request". E.g. On an 1166 AT91RM9200 processor running at 180MHz, this delay needed 1167 to be *at least* 15,000 usec before a Windows Server 2003 1168 DHCP server would reply 100% of the time. I recommend at 1169 least 50,000 usec to be safe. The alternative is to hope 1170 that one of the retries will be successful but note that 1171 the DHCP timeout and retry process takes a longer than 1172 this delay. 1173 1174 - CDP Options: 1175 CONFIG_CDP_DEVICE_ID 1176 1177 The device id used in CDP trigger frames. 1178 1179 CONFIG_CDP_DEVICE_ID_PREFIX 1180 1181 A two character string which is prefixed to the MAC address 1182 of the device. 1183 1184 CONFIG_CDP_PORT_ID 1185 1186 A printf format string which contains the ascii name of 1187 the port. Normally is set to "eth%d" which sets 1188 eth0 for the first Ethernet, eth1 for the second etc. 1189 1190 CONFIG_CDP_CAPABILITIES 1191 1192 A 32bit integer which indicates the device capabilities; 1193 0x00000010 for a normal host which does not forwards. 1194 1195 CONFIG_CDP_VERSION 1196 1197 An ascii string containing the version of the software. 1198 1199 CONFIG_CDP_PLATFORM 1200 1201 An ascii string containing the name of the platform. 1202 1203 CONFIG_CDP_TRIGGER 1204 1205 A 32bit integer sent on the trigger. 1206 1207 CONFIG_CDP_POWER_CONSUMPTION 1208 1209 A 16bit integer containing the power consumption of the 1210 device in .1 of milliwatts. 1211 1212 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1213 1214 A byte containing the id of the VLAN. 1215 1216- Status LED: CONFIG_STATUS_LED 1217 1218 Several configurations allow to display the current 1219 status using a LED. For instance, the LED will blink 1220 fast while running U-Boot code, stop blinking as 1221 soon as a reply to a BOOTP request was received, and 1222 start blinking slow once the Linux kernel is running 1223 (supported by a status LED driver in the Linux 1224 kernel). Defining CONFIG_STATUS_LED enables this 1225 feature in U-Boot. 1226 1227- CAN Support: CONFIG_CAN_DRIVER 1228 1229 Defining CONFIG_CAN_DRIVER enables CAN driver support 1230 on those systems that support this (optional) 1231 feature, like the TQM8xxL modules. 1232 1233- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1234 1235 These enable I2C serial bus commands. Defining either of 1236 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1237 include the appropriate I2C driver for the selected CPU. 1238 1239 This will allow you to use i2c commands at the u-boot 1240 command line (as long as you set CONFIG_CMD_I2C in 1241 CONFIG_COMMANDS) and communicate with i2c based realtime 1242 clock chips. See common/cmd_i2c.c for a description of the 1243 command line interface. 1244 1245 CONFIG_I2C_CMD_TREE is a recommended option that places 1246 all I2C commands under a single 'i2c' root command. The 1247 older 'imm', 'imd', 'iprobe' etc. commands are considered 1248 deprecated and may disappear in the future. 1249 1250 CONFIG_HARD_I2C selects a hardware I2C controller. 1251 1252 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1253 bit-banging) driver instead of CPM or similar hardware 1254 support for I2C. 1255 1256 There are several other quantities that must also be 1257 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1258 1259 In both cases you will need to define CFG_I2C_SPEED 1260 to be the frequency (in Hz) at which you wish your i2c bus 1261 to run and CFG_I2C_SLAVE to be the address of this node (ie 1262 the CPU's i2c node address). 1263 1264 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1265 sets the CPU up as a master node and so its address should 1266 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1267 p.16-473). So, set CFG_I2C_SLAVE to 0. 1268 1269 That's all that's required for CONFIG_HARD_I2C. 1270 1271 If you use the software i2c interface (CONFIG_SOFT_I2C) 1272 then the following macros need to be defined (examples are 1273 from include/configs/lwmon.h): 1274 1275 I2C_INIT 1276 1277 (Optional). Any commands necessary to enable the I2C 1278 controller or configure ports. 1279 1280 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1281 1282 I2C_PORT 1283 1284 (Only for MPC8260 CPU). The I/O port to use (the code 1285 assumes both bits are on the same port). Valid values 1286 are 0..3 for ports A..D. 1287 1288 I2C_ACTIVE 1289 1290 The code necessary to make the I2C data line active 1291 (driven). If the data line is open collector, this 1292 define can be null. 1293 1294 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1295 1296 I2C_TRISTATE 1297 1298 The code necessary to make the I2C data line tri-stated 1299 (inactive). If the data line is open collector, this 1300 define can be null. 1301 1302 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1303 1304 I2C_READ 1305 1306 Code that returns TRUE if the I2C data line is high, 1307 FALSE if it is low. 1308 1309 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1310 1311 I2C_SDA(bit) 1312 1313 If <bit> is TRUE, sets the I2C data line high. If it 1314 is FALSE, it clears it (low). 1315 1316 eg: #define I2C_SDA(bit) \ 1317 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1318 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1319 1320 I2C_SCL(bit) 1321 1322 If <bit> is TRUE, sets the I2C clock line high. If it 1323 is FALSE, it clears it (low). 1324 1325 eg: #define I2C_SCL(bit) \ 1326 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1327 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1328 1329 I2C_DELAY 1330 1331 This delay is invoked four times per clock cycle so this 1332 controls the rate of data transfer. The data rate thus 1333 is 1 / (I2C_DELAY * 4). Often defined to be something 1334 like: 1335 1336 #define I2C_DELAY udelay(2) 1337 1338 CFG_I2C_INIT_BOARD 1339 1340 When a board is reset during an i2c bus transfer 1341 chips might think that the current transfer is still 1342 in progress. On some boards it is possible to access 1343 the i2c SCLK line directly, either by using the 1344 processor pin as a GPIO or by having a second pin 1345 connected to the bus. If this option is defined a 1346 custom i2c_init_board() routine in boards/xxx/board.c 1347 is run early in the boot sequence. 1348 1349 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1350 1351 This option enables configuration of bi_iic_fast[] flags 1352 in u-boot bd_info structure based on u-boot environment 1353 variable "i2cfast". (see also i2cfast) 1354 1355 CONFIG_I2C_MULTI_BUS 1356 1357 This option allows the use of multiple I2C buses, each of which 1358 must have a controller. At any point in time, only one bus is 1359 active. To switch to a different bus, use the 'i2c dev' command. 1360 Note that bus numbering is zero-based. 1361 1362 CFG_I2C_NOPROBES 1363 1364 This option specifies a list of I2C devices that will be skipped 1365 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1366 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1367 pairs. Otherwise, specify a 1D array of device addresses 1368 1369 e.g. 1370 #undef CONFIG_I2C_MULTI_BUS 1371 #define CFG_I2C_NOPROBES {0x50,0x68} 1372 1373 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1374 1375 #define CONFIG_I2C_MULTI_BUS 1376 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1377 1378 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1379 1380 CFG_SPD_BUS_NUM 1381 1382 If defined, then this indicates the I2C bus number for DDR SPD. 1383 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1384 1385 CFG_RTC_BUS_NUM 1386 1387 If defined, then this indicates the I2C bus number for the RTC. 1388 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1389 1390 CFG_DTT_BUS_NUM 1391 1392 If defined, then this indicates the I2C bus number for the DTT. 1393 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1394 1395 CFG_I2C_DTT_ADDR: 1396 1397 If defined, specifies the I2C address of the DTT device. 1398 If not defined, then U-Boot uses predefined value for 1399 specified DTT device. 1400 1401 CONFIG_FSL_I2C 1402 1403 Define this option if you want to use Freescale's I2C driver in 1404 drivers/i2c/fsl_i2c.c. 1405 1406 1407- SPI Support: CONFIG_SPI 1408 1409 Enables SPI driver (so far only tested with 1410 SPI EEPROM, also an instance works with Crystal A/D and 1411 D/As on the SACSng board) 1412 1413 CONFIG_SPI_X 1414 1415 Enables extended (16-bit) SPI EEPROM addressing. 1416 (symmetrical to CONFIG_I2C_X) 1417 1418 CONFIG_SOFT_SPI 1419 1420 Enables a software (bit-bang) SPI driver rather than 1421 using hardware support. This is a general purpose 1422 driver that only requires three general I/O port pins 1423 (two outputs, one input) to function. If this is 1424 defined, the board configuration must define several 1425 SPI configuration items (port pins to use, etc). For 1426 an example, see include/configs/sacsng.h. 1427 1428 CONFIG_HARD_SPI 1429 1430 Enables a hardware SPI driver for general-purpose reads 1431 and writes. As with CONFIG_SOFT_SPI, the board configuration 1432 must define a list of chip-select function pointers. 1433 Currently supported on some MPC8xxx processors. For an 1434 example, see include/configs/mpc8349emds.h. 1435 1436 CONFIG_MXC_SPI 1437 1438 Enables the driver for the SPI controllers on i.MX and MXC 1439 SoCs. Currently only i.MX31 is supported. 1440 1441- FPGA Support: CONFIG_FPGA 1442 1443 Enables FPGA subsystem. 1444 1445 CONFIG_FPGA_<vendor> 1446 1447 Enables support for specific chip vendors. 1448 (ALTERA, XILINX) 1449 1450 CONFIG_FPGA_<family> 1451 1452 Enables support for FPGA family. 1453 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1454 1455 CONFIG_FPGA_COUNT 1456 1457 Specify the number of FPGA devices to support. 1458 1459 CFG_FPGA_PROG_FEEDBACK 1460 1461 Enable printing of hash marks during FPGA configuration. 1462 1463 CFG_FPGA_CHECK_BUSY 1464 1465 Enable checks on FPGA configuration interface busy 1466 status by the configuration function. This option 1467 will require a board or device specific function to 1468 be written. 1469 1470 CONFIG_FPGA_DELAY 1471 1472 If defined, a function that provides delays in the FPGA 1473 configuration driver. 1474 1475 CFG_FPGA_CHECK_CTRLC 1476 Allow Control-C to interrupt FPGA configuration 1477 1478 CFG_FPGA_CHECK_ERROR 1479 1480 Check for configuration errors during FPGA bitfile 1481 loading. For example, abort during Virtex II 1482 configuration if the INIT_B line goes low (which 1483 indicated a CRC error). 1484 1485 CFG_FPGA_WAIT_INIT 1486 1487 Maximum time to wait for the INIT_B line to deassert 1488 after PROB_B has been deasserted during a Virtex II 1489 FPGA configuration sequence. The default time is 500 1490 ms. 1491 1492 CFG_FPGA_WAIT_BUSY 1493 1494 Maximum time to wait for BUSY to deassert during 1495 Virtex II FPGA configuration. The default is 5 ms. 1496 1497 CFG_FPGA_WAIT_CONFIG 1498 1499 Time to wait after FPGA configuration. The default is 1500 200 ms. 1501 1502- Configuration Management: 1503 CONFIG_IDENT_STRING 1504 1505 If defined, this string will be added to the U-Boot 1506 version information (U_BOOT_VERSION) 1507 1508- Vendor Parameter Protection: 1509 1510 U-Boot considers the values of the environment 1511 variables "serial#" (Board Serial Number) and 1512 "ethaddr" (Ethernet Address) to be parameters that 1513 are set once by the board vendor / manufacturer, and 1514 protects these variables from casual modification by 1515 the user. Once set, these variables are read-only, 1516 and write or delete attempts are rejected. You can 1517 change this behaviour: 1518 1519 If CONFIG_ENV_OVERWRITE is #defined in your config 1520 file, the write protection for vendor parameters is 1521 completely disabled. Anybody can change or delete 1522 these parameters. 1523 1524 Alternatively, if you #define _both_ CONFIG_ETHADDR 1525 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1526 Ethernet address is installed in the environment, 1527 which can be changed exactly ONCE by the user. [The 1528 serial# is unaffected by this, i. e. it remains 1529 read-only.] 1530 1531- Protected RAM: 1532 CONFIG_PRAM 1533 1534 Define this variable to enable the reservation of 1535 "protected RAM", i. e. RAM which is not overwritten 1536 by U-Boot. Define CONFIG_PRAM to hold the number of 1537 kB you want to reserve for pRAM. You can overwrite 1538 this default value by defining an environment 1539 variable "pram" to the number of kB you want to 1540 reserve. Note that the board info structure will 1541 still show the full amount of RAM. If pRAM is 1542 reserved, a new environment variable "mem" will 1543 automatically be defined to hold the amount of 1544 remaining RAM in a form that can be passed as boot 1545 argument to Linux, for instance like that: 1546 1547 setenv bootargs ... mem=\${mem} 1548 saveenv 1549 1550 This way you can tell Linux not to use this memory, 1551 either, which results in a memory region that will 1552 not be affected by reboots. 1553 1554 *WARNING* If your board configuration uses automatic 1555 detection of the RAM size, you must make sure that 1556 this memory test is non-destructive. So far, the 1557 following board configurations are known to be 1558 "pRAM-clean": 1559 1560 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1561 HERMES, IP860, RPXlite, LWMON, LANTEC, 1562 PCU_E, FLAGADM, TQM8260 1563 1564- Error Recovery: 1565 CONFIG_PANIC_HANG 1566 1567 Define this variable to stop the system in case of a 1568 fatal error, so that you have to reset it manually. 1569 This is probably NOT a good idea for an embedded 1570 system where you want the system to reboot 1571 automatically as fast as possible, but it may be 1572 useful during development since you can try to debug 1573 the conditions that lead to the situation. 1574 1575 CONFIG_NET_RETRY_COUNT 1576 1577 This variable defines the number of retries for 1578 network operations like ARP, RARP, TFTP, or BOOTP 1579 before giving up the operation. If not defined, a 1580 default value of 5 is used. 1581 1582 CONFIG_ARP_TIMEOUT 1583 1584 Timeout waiting for an ARP reply in milliseconds. 1585 1586- Command Interpreter: 1587 CONFIG_AUTO_COMPLETE 1588 1589 Enable auto completion of commands using TAB. 1590 1591 Note that this feature has NOT been implemented yet 1592 for the "hush" shell. 1593 1594 1595 CFG_HUSH_PARSER 1596 1597 Define this variable to enable the "hush" shell (from 1598 Busybox) as command line interpreter, thus enabling 1599 powerful command line syntax like 1600 if...then...else...fi conditionals or `&&' and '||' 1601 constructs ("shell scripts"). 1602 1603 If undefined, you get the old, much simpler behaviour 1604 with a somewhat smaller memory footprint. 1605 1606 1607 CFG_PROMPT_HUSH_PS2 1608 1609 This defines the secondary prompt string, which is 1610 printed when the command interpreter needs more input 1611 to complete a command. Usually "> ". 1612 1613 Note: 1614 1615 In the current implementation, the local variables 1616 space and global environment variables space are 1617 separated. Local variables are those you define by 1618 simply typing `name=value'. To access a local 1619 variable later on, you have write `$name' or 1620 `${name}'; to execute the contents of a variable 1621 directly type `$name' at the command prompt. 1622 1623 Global environment variables are those you use 1624 setenv/printenv to work with. To run a command stored 1625 in such a variable, you need to use the run command, 1626 and you must not use the '$' sign to access them. 1627 1628 To store commands and special characters in a 1629 variable, please use double quotation marks 1630 surrounding the whole text of the variable, instead 1631 of the backslashes before semicolons and special 1632 symbols. 1633 1634- Commandline Editing and History: 1635 CONFIG_CMDLINE_EDITING 1636 1637 Enable editing and History functions for interactive 1638 commandline input operations 1639 1640- Default Environment: 1641 CONFIG_EXTRA_ENV_SETTINGS 1642 1643 Define this to contain any number of null terminated 1644 strings (variable = value pairs) that will be part of 1645 the default environment compiled into the boot image. 1646 1647 For example, place something like this in your 1648 board's config file: 1649 1650 #define CONFIG_EXTRA_ENV_SETTINGS \ 1651 "myvar1=value1\0" \ 1652 "myvar2=value2\0" 1653 1654 Warning: This method is based on knowledge about the 1655 internal format how the environment is stored by the 1656 U-Boot code. This is NOT an official, exported 1657 interface! Although it is unlikely that this format 1658 will change soon, there is no guarantee either. 1659 You better know what you are doing here. 1660 1661 Note: overly (ab)use of the default environment is 1662 discouraged. Make sure to check other ways to preset 1663 the environment like the autoscript function or the 1664 boot command first. 1665 1666- DataFlash Support: 1667 CONFIG_HAS_DATAFLASH 1668 1669 Defining this option enables DataFlash features and 1670 allows to read/write in Dataflash via the standard 1671 commands cp, md... 1672 1673- SystemACE Support: 1674 CONFIG_SYSTEMACE 1675 1676 Adding this option adds support for Xilinx SystemACE 1677 chips attached via some sort of local bus. The address 1678 of the chip must also be defined in the 1679 CFG_SYSTEMACE_BASE macro. For example: 1680 1681 #define CONFIG_SYSTEMACE 1682 #define CFG_SYSTEMACE_BASE 0xf0000000 1683 1684 When SystemACE support is added, the "ace" device type 1685 becomes available to the fat commands, i.e. fatls. 1686 1687- TFTP Fixed UDP Port: 1688 CONFIG_TFTP_PORT 1689 1690 If this is defined, the environment variable tftpsrcp 1691 is used to supply the TFTP UDP source port value. 1692 If tftpsrcp isn't defined, the normal pseudo-random port 1693 number generator is used. 1694 1695 Also, the environment variable tftpdstp is used to supply 1696 the TFTP UDP destination port value. If tftpdstp isn't 1697 defined, the normal port 69 is used. 1698 1699 The purpose for tftpsrcp is to allow a TFTP server to 1700 blindly start the TFTP transfer using the pre-configured 1701 target IP address and UDP port. This has the effect of 1702 "punching through" the (Windows XP) firewall, allowing 1703 the remainder of the TFTP transfer to proceed normally. 1704 A better solution is to properly configure the firewall, 1705 but sometimes that is not allowed. 1706 1707- Show boot progress: 1708 CONFIG_SHOW_BOOT_PROGRESS 1709 1710 Defining this option allows to add some board- 1711 specific code (calling a user-provided function 1712 "show_boot_progress(int)") that enables you to show 1713 the system's boot progress on some display (for 1714 example, some LED's) on your board. At the moment, 1715 the following checkpoints are implemented: 1716 1717Legacy uImage format: 1718 1719 Arg Where When 1720 1 common/cmd_bootm.c before attempting to boot an image 1721 -1 common/cmd_bootm.c Image header has bad magic number 1722 2 common/cmd_bootm.c Image header has correct magic number 1723 -2 common/cmd_bootm.c Image header has bad checksum 1724 3 common/cmd_bootm.c Image header has correct checksum 1725 -3 common/cmd_bootm.c Image data has bad checksum 1726 4 common/cmd_bootm.c Image data has correct checksum 1727 -4 common/cmd_bootm.c Image is for unsupported architecture 1728 5 common/cmd_bootm.c Architecture check OK 1729 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 1730 6 common/cmd_bootm.c Image Type check OK 1731 -6 common/cmd_bootm.c gunzip uncompression error 1732 -7 common/cmd_bootm.c Unimplemented compression type 1733 7 common/cmd_bootm.c Uncompression OK 1734 8 common/cmd_bootm.c No uncompress/copy overwrite error 1735 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1736 1737 9 common/image.c Start initial ramdisk verification 1738 -10 common/image.c Ramdisk header has bad magic number 1739 -11 common/image.c Ramdisk header has bad checksum 1740 10 common/image.c Ramdisk header is OK 1741 -12 common/image.c Ramdisk data has bad checksum 1742 11 common/image.c Ramdisk data has correct checksum 1743 12 common/image.c Ramdisk verification complete, start loading 1744 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 1745 13 common/image.c Start multifile image verification 1746 14 common/image.c No initial ramdisk, no multifile, continue. 1747 1748 15 lib_<arch>/bootm.c All preparation done, transferring control to OS 1749 1750 -30 lib_ppc/board.c Fatal error, hang the system 1751 -31 post/post.c POST test failed, detected by post_output_backlog() 1752 -32 post/post.c POST test failed, detected by post_run_single() 1753 1754 34 common/cmd_doc.c before loading a Image from a DOC device 1755 -35 common/cmd_doc.c Bad usage of "doc" command 1756 35 common/cmd_doc.c correct usage of "doc" command 1757 -36 common/cmd_doc.c No boot device 1758 36 common/cmd_doc.c correct boot device 1759 -37 common/cmd_doc.c Unknown Chip ID on boot device 1760 37 common/cmd_doc.c correct chip ID found, device available 1761 -38 common/cmd_doc.c Read Error on boot device 1762 38 common/cmd_doc.c reading Image header from DOC device OK 1763 -39 common/cmd_doc.c Image header has bad magic number 1764 39 common/cmd_doc.c Image header has correct magic number 1765 -40 common/cmd_doc.c Error reading Image from DOC device 1766 40 common/cmd_doc.c Image header has correct magic number 1767 41 common/cmd_ide.c before loading a Image from a IDE device 1768 -42 common/cmd_ide.c Bad usage of "ide" command 1769 42 common/cmd_ide.c correct usage of "ide" command 1770 -43 common/cmd_ide.c No boot device 1771 43 common/cmd_ide.c boot device found 1772 -44 common/cmd_ide.c Device not available 1773 44 common/cmd_ide.c Device available 1774 -45 common/cmd_ide.c wrong partition selected 1775 45 common/cmd_ide.c partition selected 1776 -46 common/cmd_ide.c Unknown partition table 1777 46 common/cmd_ide.c valid partition table found 1778 -47 common/cmd_ide.c Invalid partition type 1779 47 common/cmd_ide.c correct partition type 1780 -48 common/cmd_ide.c Error reading Image Header on boot device 1781 48 common/cmd_ide.c reading Image Header from IDE device OK 1782 -49 common/cmd_ide.c Image header has bad magic number 1783 49 common/cmd_ide.c Image header has correct magic number 1784 -50 common/cmd_ide.c Image header has bad checksum 1785 50 common/cmd_ide.c Image header has correct checksum 1786 -51 common/cmd_ide.c Error reading Image from IDE device 1787 51 common/cmd_ide.c reading Image from IDE device OK 1788 52 common/cmd_nand.c before loading a Image from a NAND device 1789 -53 common/cmd_nand.c Bad usage of "nand" command 1790 53 common/cmd_nand.c correct usage of "nand" command 1791 -54 common/cmd_nand.c No boot device 1792 54 common/cmd_nand.c boot device found 1793 -55 common/cmd_nand.c Unknown Chip ID on boot device 1794 55 common/cmd_nand.c correct chip ID found, device available 1795 -56 common/cmd_nand.c Error reading Image Header on boot device 1796 56 common/cmd_nand.c reading Image Header from NAND device OK 1797 -57 common/cmd_nand.c Image header has bad magic number 1798 57 common/cmd_nand.c Image header has correct magic number 1799 -58 common/cmd_nand.c Error reading Image from NAND device 1800 58 common/cmd_nand.c reading Image from NAND device OK 1801 1802 -60 common/env_common.c Environment has a bad CRC, using default 1803 1804 64 net/eth.c starting with Ethernet configuration. 1805 -64 net/eth.c no Ethernet found. 1806 65 net/eth.c Ethernet found. 1807 1808 -80 common/cmd_net.c usage wrong 1809 80 common/cmd_net.c before calling NetLoop() 1810 -81 common/cmd_net.c some error in NetLoop() occurred 1811 81 common/cmd_net.c NetLoop() back without error 1812 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 1813 82 common/cmd_net.c trying automatic boot 1814 83 common/cmd_net.c running autoscript 1815 -83 common/cmd_net.c some error in automatic boot or autoscript 1816 84 common/cmd_net.c end without errors 1817 1818FIT uImage format: 1819 1820 Arg Where When 1821 100 common/cmd_bootm.c Kernel FIT Image has correct format 1822 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 1823 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 1824 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 1825 102 common/cmd_bootm.c Kernel unit name specified 1826 -103 common/cmd_bootm.c Can't get kernel subimage node offset 1827 103 common/cmd_bootm.c Found configuration node 1828 104 common/cmd_bootm.c Got kernel subimage node offset 1829 -104 common/cmd_bootm.c Kernel subimage hash verification failed 1830 105 common/cmd_bootm.c Kernel subimage hash verification OK 1831 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 1832 106 common/cmd_bootm.c Architecture check OK 1833 -106 common/cmd_bootm.c Kernel subimage has wrong type 1834 107 common/cmd_bootm.c Kernel subimage type OK 1835 -107 common/cmd_bootm.c Can't get kernel subimage data/size 1836 108 common/cmd_bootm.c Got kernel subimage data/size 1837 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 1838 -109 common/cmd_bootm.c Can't get kernel subimage type 1839 -110 common/cmd_bootm.c Can't get kernel subimage comp 1840 -111 common/cmd_bootm.c Can't get kernel subimage os 1841 -112 common/cmd_bootm.c Can't get kernel subimage load address 1842 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 1843 1844 120 common/image.c Start initial ramdisk verification 1845 -120 common/image.c Ramdisk FIT image has incorrect format 1846 121 common/image.c Ramdisk FIT image has correct format 1847 122 common/image.c No ramdisk subimage unit name, using configuration 1848 -122 common/image.c Can't get configuration for ramdisk subimage 1849 123 common/image.c Ramdisk unit name specified 1850 -124 common/image.c Can't get ramdisk subimage node offset 1851 125 common/image.c Got ramdisk subimage node offset 1852 -125 common/image.c Ramdisk subimage hash verification failed 1853 126 common/image.c Ramdisk subimage hash verification OK 1854 -126 common/image.c Ramdisk subimage for unsupported architecture 1855 127 common/image.c Architecture check OK 1856 -127 common/image.c Can't get ramdisk subimage data/size 1857 128 common/image.c Got ramdisk subimage data/size 1858 129 common/image.c Can't get ramdisk load address 1859 -129 common/image.c Got ramdisk load address 1860 1861 -130 common/cmd_doc.c Incorrect FIT image format 1862 131 common/cmd_doc.c FIT image format OK 1863 1864 -140 common/cmd_ide.c Incorrect FIT image format 1865 141 common/cmd_ide.c FIT image format OK 1866 1867 -150 common/cmd_nand.c Incorrect FIT image format 1868 151 common/cmd_nand.c FIT image format OK 1869 1870 1871Modem Support: 1872-------------- 1873 1874[so far only for SMDK2400 and TRAB boards] 1875 1876- Modem support enable: 1877 CONFIG_MODEM_SUPPORT 1878 1879- RTS/CTS Flow control enable: 1880 CONFIG_HWFLOW 1881 1882- Modem debug support: 1883 CONFIG_MODEM_SUPPORT_DEBUG 1884 1885 Enables debugging stuff (char screen[1024], dbg()) 1886 for modem support. Useful only with BDI2000. 1887 1888- Interrupt support (PPC): 1889 1890 There are common interrupt_init() and timer_interrupt() 1891 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1892 for CPU specific initialization. interrupt_init_cpu() 1893 should set decrementer_count to appropriate value. If 1894 CPU resets decrementer automatically after interrupt 1895 (ppc4xx) it should set decrementer_count to zero. 1896 timer_interrupt() calls timer_interrupt_cpu() for CPU 1897 specific handling. If board has watchdog / status_led 1898 / other_activity_monitor it works automatically from 1899 general timer_interrupt(). 1900 1901- General: 1902 1903 In the target system modem support is enabled when a 1904 specific key (key combination) is pressed during 1905 power-on. Otherwise U-Boot will boot normally 1906 (autoboot). The key_pressed() function is called from 1907 board_init(). Currently key_pressed() is a dummy 1908 function, returning 1 and thus enabling modem 1909 initialization. 1910 1911 If there are no modem init strings in the 1912 environment, U-Boot proceed to autoboot; the 1913 previous output (banner, info printfs) will be 1914 suppressed, though. 1915 1916 See also: doc/README.Modem 1917 1918 1919Configuration Settings: 1920----------------------- 1921 1922- CFG_LONGHELP: Defined when you want long help messages included; 1923 undefine this when you're short of memory. 1924 1925- CFG_PROMPT: This is what U-Boot prints on the console to 1926 prompt for user input. 1927 1928- CFG_CBSIZE: Buffer size for input from the Console 1929 1930- CFG_PBSIZE: Buffer size for Console output 1931 1932- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1933 1934- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1935 the application (usually a Linux kernel) when it is 1936 booted 1937 1938- CFG_BAUDRATE_TABLE: 1939 List of legal baudrate settings for this board. 1940 1941- CFG_CONSOLE_INFO_QUIET 1942 Suppress display of console information at boot. 1943 1944- CFG_CONSOLE_IS_IN_ENV 1945 If the board specific function 1946 extern int overwrite_console (void); 1947 returns 1, the stdin, stderr and stdout are switched to the 1948 serial port, else the settings in the environment are used. 1949 1950- CFG_CONSOLE_OVERWRITE_ROUTINE 1951 Enable the call to overwrite_console(). 1952 1953- CFG_CONSOLE_ENV_OVERWRITE 1954 Enable overwrite of previous console environment settings. 1955 1956- CFG_MEMTEST_START, CFG_MEMTEST_END: 1957 Begin and End addresses of the area used by the 1958 simple memory test. 1959 1960- CFG_ALT_MEMTEST: 1961 Enable an alternate, more extensive memory test. 1962 1963- CFG_MEMTEST_SCRATCH: 1964 Scratch address used by the alternate memory test 1965 You only need to set this if address zero isn't writeable 1966 1967- CFG_MEM_TOP_HIDE (PPC only): 1968 If CFG_MEM_TOP_HIDE is defined in the board config header, 1969 this specified memory area will get subtracted from the top 1970 (end) of RAM and won't get "touched" at all by U-Boot. By 1971 fixing up gd->ram_size the Linux kernel should gets passed 1972 the now "corrected" memory size and won't touch it either. 1973 This should work for arch/ppc and arch/powerpc. Only Linux 1974 board ports in arch/powerpc with bootwrapper support that 1975 recalculate the memory size from the SDRAM controller setup 1976 will have to get fixed in Linux additionally. 1977 1978 This option can be used as a workaround for the 440EPx/GRx 1979 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 1980 be touched. 1981 1982 WARNING: Please make sure that this value is a multiple of 1983 the Linux page size (normally 4k). If this is not the case, 1984 then the end address of the Linux memory will be located at a 1985 non page size aligned address and this could cause major 1986 problems. 1987 1988- CFG_TFTP_LOADADDR: 1989 Default load address for network file downloads 1990 1991- CFG_LOADS_BAUD_CHANGE: 1992 Enable temporary baudrate change while serial download 1993 1994- CFG_SDRAM_BASE: 1995 Physical start address of SDRAM. _Must_ be 0 here. 1996 1997- CFG_MBIO_BASE: 1998 Physical start address of Motherboard I/O (if using a 1999 Cogent motherboard) 2000 2001- CFG_FLASH_BASE: 2002 Physical start address of Flash memory. 2003 2004- CFG_MONITOR_BASE: 2005 Physical start address of boot monitor code (set by 2006 make config files to be same as the text base address 2007 (TEXT_BASE) used when linking) - same as 2008 CFG_FLASH_BASE when booting from flash. 2009 2010- CFG_MONITOR_LEN: 2011 Size of memory reserved for monitor code, used to 2012 determine _at_compile_time_ (!) if the environment is 2013 embedded within the U-Boot image, or in a separate 2014 flash sector. 2015 2016- CFG_MALLOC_LEN: 2017 Size of DRAM reserved for malloc() use. 2018 2019- CFG_BOOTM_LEN: 2020 Normally compressed uImages are limited to an 2021 uncompressed size of 8 MBytes. If this is not enough, 2022 you can define CFG_BOOTM_LEN in your board config file 2023 to adjust this setting to your needs. 2024 2025- CFG_BOOTMAPSZ: 2026 Maximum size of memory mapped by the startup code of 2027 the Linux kernel; all data that must be processed by 2028 the Linux kernel (bd_info, boot arguments, FDT blob if 2029 used) must be put below this limit, unless "bootm_low" 2030 enviroment variable is defined and non-zero. In such case 2031 all data for the Linux kernel must be between "bootm_low" 2032 and "bootm_low" + CFG_BOOTMAPSZ. 2033 2034- CFG_MAX_FLASH_BANKS: 2035 Max number of Flash memory banks 2036 2037- CFG_MAX_FLASH_SECT: 2038 Max number of sectors on a Flash chip 2039 2040- CFG_FLASH_ERASE_TOUT: 2041 Timeout for Flash erase operations (in ms) 2042 2043- CFG_FLASH_WRITE_TOUT: 2044 Timeout for Flash write operations (in ms) 2045 2046- CFG_FLASH_LOCK_TOUT 2047 Timeout for Flash set sector lock bit operation (in ms) 2048 2049- CFG_FLASH_UNLOCK_TOUT 2050 Timeout for Flash clear lock bits operation (in ms) 2051 2052- CFG_FLASH_PROTECTION 2053 If defined, hardware flash sectors protection is used 2054 instead of U-Boot software protection. 2055 2056- CFG_DIRECT_FLASH_TFTP: 2057 2058 Enable TFTP transfers directly to flash memory; 2059 without this option such a download has to be 2060 performed in two steps: (1) download to RAM, and (2) 2061 copy from RAM to flash. 2062 2063 The two-step approach is usually more reliable, since 2064 you can check if the download worked before you erase 2065 the flash, but in some situations (when system RAM is 2066 too limited to allow for a temporary copy of the 2067 downloaded image) this option may be very useful. 2068 2069- CFG_FLASH_CFI: 2070 Define if the flash driver uses extra elements in the 2071 common flash structure for storing flash geometry. 2072 2073- CONFIG_FLASH_CFI_DRIVER 2074 This option also enables the building of the cfi_flash driver 2075 in the drivers directory 2076 2077- CFG_FLASH_USE_BUFFER_WRITE 2078 Use buffered writes to flash. 2079 2080- CONFIG_FLASH_SPANSION_S29WS_N 2081 s29ws-n MirrorBit flash has non-standard addresses for buffered 2082 write commands. 2083 2084- CFG_FLASH_QUIET_TEST 2085 If this option is defined, the common CFI flash doesn't 2086 print it's warning upon not recognized FLASH banks. This 2087 is useful, if some of the configured banks are only 2088 optionally available. 2089 2090- CONFIG_FLASH_SHOW_PROGRESS 2091 If defined (must be an integer), print out countdown 2092 digits and dots. Recommended value: 45 (9..1) for 80 2093 column displays, 15 (3..1) for 40 column displays. 2094 2095- CFG_RX_ETH_BUFFER: 2096 Defines the number of Ethernet receive buffers. On some 2097 Ethernet controllers it is recommended to set this value 2098 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2099 buffers can be full shortly after enabling the interface 2100 on high Ethernet traffic. 2101 Defaults to 4 if not defined. 2102 2103The following definitions that deal with the placement and management 2104of environment data (variable area); in general, we support the 2105following configurations: 2106 2107- CFG_ENV_IS_IN_FLASH: 2108 2109 Define this if the environment is in flash memory. 2110 2111 a) The environment occupies one whole flash sector, which is 2112 "embedded" in the text segment with the U-Boot code. This 2113 happens usually with "bottom boot sector" or "top boot 2114 sector" type flash chips, which have several smaller 2115 sectors at the start or the end. For instance, such a 2116 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2117 such a case you would place the environment in one of the 2118 4 kB sectors - with U-Boot code before and after it. With 2119 "top boot sector" type flash chips, you would put the 2120 environment in one of the last sectors, leaving a gap 2121 between U-Boot and the environment. 2122 2123 - CFG_ENV_OFFSET: 2124 2125 Offset of environment data (variable area) to the 2126 beginning of flash memory; for instance, with bottom boot 2127 type flash chips the second sector can be used: the offset 2128 for this sector is given here. 2129 2130 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 2131 2132 - CFG_ENV_ADDR: 2133 2134 This is just another way to specify the start address of 2135 the flash sector containing the environment (instead of 2136 CFG_ENV_OFFSET). 2137 2138 - CFG_ENV_SECT_SIZE: 2139 2140 Size of the sector containing the environment. 2141 2142 2143 b) Sometimes flash chips have few, equal sized, BIG sectors. 2144 In such a case you don't want to spend a whole sector for 2145 the environment. 2146 2147 - CFG_ENV_SIZE: 2148 2149 If you use this in combination with CFG_ENV_IS_IN_FLASH 2150 and CFG_ENV_SECT_SIZE, you can specify to use only a part 2151 of this flash sector for the environment. This saves 2152 memory for the RAM copy of the environment. 2153 2154 It may also save flash memory if you decide to use this 2155 when your environment is "embedded" within U-Boot code, 2156 since then the remainder of the flash sector could be used 2157 for U-Boot code. It should be pointed out that this is 2158 STRONGLY DISCOURAGED from a robustness point of view: 2159 updating the environment in flash makes it always 2160 necessary to erase the WHOLE sector. If something goes 2161 wrong before the contents has been restored from a copy in 2162 RAM, your target system will be dead. 2163 2164 - CFG_ENV_ADDR_REDUND 2165 CFG_ENV_SIZE_REDUND 2166 2167 These settings describe a second storage area used to hold 2168 a redundant copy of the environment data, so that there is 2169 a valid backup copy in case there is a power failure during 2170 a "saveenv" operation. 2171 2172BE CAREFUL! Any changes to the flash layout, and some changes to the 2173source code will make it necessary to adapt <board>/u-boot.lds* 2174accordingly! 2175 2176 2177- CONFIG_ENV_IS_IN_NVRAM: 2178 2179 Define this if you have some non-volatile memory device 2180 (NVRAM, battery buffered SRAM) which you want to use for the 2181 environment. 2182 2183 - CFG_ENV_ADDR: 2184 - CFG_ENV_SIZE: 2185 2186 These two #defines are used to determine the memory area you 2187 want to use for environment. It is assumed that this memory 2188 can just be read and written to, without any special 2189 provision. 2190 2191BE CAREFUL! The first access to the environment happens quite early 2192in U-Boot initalization (when we try to get the setting of for the 2193console baudrate). You *MUST* have mapped your NVRAM area then, or 2194U-Boot will hang. 2195 2196Please note that even with NVRAM we still use a copy of the 2197environment in RAM: we could work on NVRAM directly, but we want to 2198keep settings there always unmodified except somebody uses "saveenv" 2199to save the current settings. 2200 2201 2202- CONFIG_ENV_IS_IN_EEPROM: 2203 2204 Use this if you have an EEPROM or similar serial access 2205 device and a driver for it. 2206 2207 - CFG_ENV_OFFSET: 2208 - CFG_ENV_SIZE: 2209 2210 These two #defines specify the offset and size of the 2211 environment area within the total memory of your EEPROM. 2212 2213 - CFG_I2C_EEPROM_ADDR: 2214 If defined, specified the chip address of the EEPROM device. 2215 The default address is zero. 2216 2217 - CFG_EEPROM_PAGE_WRITE_BITS: 2218 If defined, the number of bits used to address bytes in a 2219 single page in the EEPROM device. A 64 byte page, for example 2220 would require six bits. 2221 2222 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2223 If defined, the number of milliseconds to delay between 2224 page writes. The default is zero milliseconds. 2225 2226 - CFG_I2C_EEPROM_ADDR_LEN: 2227 The length in bytes of the EEPROM memory array address. Note 2228 that this is NOT the chip address length! 2229 2230 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2231 EEPROM chips that implement "address overflow" are ones 2232 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2233 address and the extra bits end up in the "chip address" bit 2234 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2235 byte chips. 2236 2237 Note that we consider the length of the address field to 2238 still be one byte because the extra address bits are hidden 2239 in the chip address. 2240 2241 - CFG_EEPROM_SIZE: 2242 The size in bytes of the EEPROM device. 2243 2244 2245- CONFIG_ENV_IS_IN_DATAFLASH: 2246 2247 Define this if you have a DataFlash memory device which you 2248 want to use for the environment. 2249 2250 - CFG_ENV_OFFSET: 2251 - CFG_ENV_ADDR: 2252 - CFG_ENV_SIZE: 2253 2254 These three #defines specify the offset and size of the 2255 environment area within the total memory of your DataFlash placed 2256 at the specified address. 2257 2258- CONFIG_ENV_IS_IN_NAND: 2259 2260 Define this if you have a NAND device which you want to use 2261 for the environment. 2262 2263 - CFG_ENV_OFFSET: 2264 - CFG_ENV_SIZE: 2265 2266 These two #defines specify the offset and size of the environment 2267 area within the first NAND device. 2268 2269 - CFG_ENV_OFFSET_REDUND 2270 2271 This setting describes a second storage area of CFG_ENV_SIZE 2272 size used to hold a redundant copy of the environment data, 2273 so that there is a valid backup copy in case there is a 2274 power failure during a "saveenv" operation. 2275 2276 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2277 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2278 the NAND devices block size. 2279 2280- CFG_SPI_INIT_OFFSET 2281 2282 Defines offset to the initial SPI buffer area in DPRAM. The 2283 area is used at an early stage (ROM part) if the environment 2284 is configured to reside in the SPI EEPROM: We need a 520 byte 2285 scratch DPRAM area. It is used between the two initialization 2286 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2287 to be a good choice since it makes it far enough from the 2288 start of the data area as well as from the stack pointer. 2289 2290Please note that the environment is read-only until the monitor 2291has been relocated to RAM and a RAM copy of the environment has been 2292created; also, when using EEPROM you will have to use getenv_r() 2293until then to read environment variables. 2294 2295The environment is protected by a CRC32 checksum. Before the monitor 2296is relocated into RAM, as a result of a bad CRC you will be working 2297with the compiled-in default environment - *silently*!!! [This is 2298necessary, because the first environment variable we need is the 2299"baudrate" setting for the console - if we have a bad CRC, we don't 2300have any device yet where we could complain.] 2301 2302Note: once the monitor has been relocated, then it will complain if 2303the default environment is used; a new CRC is computed as soon as you 2304use the "saveenv" command to store a valid environment. 2305 2306- CFG_FAULT_ECHO_LINK_DOWN: 2307 Echo the inverted Ethernet link state to the fault LED. 2308 2309 Note: If this option is active, then CFG_FAULT_MII_ADDR 2310 also needs to be defined. 2311 2312- CFG_FAULT_MII_ADDR: 2313 MII address of the PHY to check for the Ethernet link state. 2314 2315- CFG_64BIT_VSPRINTF: 2316 Makes vsprintf (and all *printf functions) support printing 2317 of 64bit values by using the L quantifier 2318 2319- CFG_64BIT_STRTOUL: 2320 Adds simple_strtoull that returns a 64bit value 2321 2322Low Level (hardware related) configuration options: 2323--------------------------------------------------- 2324 2325- CFG_CACHELINE_SIZE: 2326 Cache Line Size of the CPU. 2327 2328- CFG_DEFAULT_IMMR: 2329 Default address of the IMMR after system reset. 2330 2331 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2332 and RPXsuper) to be able to adjust the position of 2333 the IMMR register after a reset. 2334 2335- Floppy Disk Support: 2336 CFG_FDC_DRIVE_NUMBER 2337 2338 the default drive number (default value 0) 2339 2340 CFG_ISA_IO_STRIDE 2341 2342 defines the spacing between FDC chipset registers 2343 (default value 1) 2344 2345 CFG_ISA_IO_OFFSET 2346 2347 defines the offset of register from address. It 2348 depends on which part of the data bus is connected to 2349 the FDC chipset. (default value 0) 2350 2351 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2352 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2353 default value. 2354 2355 if CFG_FDC_HW_INIT is defined, then the function 2356 fdc_hw_init() is called at the beginning of the FDC 2357 setup. fdc_hw_init() must be provided by the board 2358 source code. It is used to make hardware dependant 2359 initializations. 2360 2361- CFG_IMMR: Physical address of the Internal Memory. 2362 DO NOT CHANGE unless you know exactly what you're 2363 doing! (11-4) [MPC8xx/82xx systems only] 2364 2365- CFG_INIT_RAM_ADDR: 2366 2367 Start address of memory area that can be used for 2368 initial data and stack; please note that this must be 2369 writable memory that is working WITHOUT special 2370 initialization, i. e. you CANNOT use normal RAM which 2371 will become available only after programming the 2372 memory controller and running certain initialization 2373 sequences. 2374 2375 U-Boot uses the following memory types: 2376 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2377 - MPC824X: data cache 2378 - PPC4xx: data cache 2379 2380- CFG_GBL_DATA_OFFSET: 2381 2382 Offset of the initial data structure in the memory 2383 area defined by CFG_INIT_RAM_ADDR. Usually 2384 CFG_GBL_DATA_OFFSET is chosen such that the initial 2385 data is located at the end of the available space 2386 (sometimes written as (CFG_INIT_RAM_END - 2387 CFG_INIT_DATA_SIZE), and the initial stack is just 2388 below that area (growing from (CFG_INIT_RAM_ADDR + 2389 CFG_GBL_DATA_OFFSET) downward. 2390 2391 Note: 2392 On the MPC824X (or other systems that use the data 2393 cache for initial memory) the address chosen for 2394 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2395 point to an otherwise UNUSED address space between 2396 the top of RAM and the start of the PCI space. 2397 2398- CFG_SIUMCR: SIU Module Configuration (11-6) 2399 2400- CFG_SYPCR: System Protection Control (11-9) 2401 2402- CFG_TBSCR: Time Base Status and Control (11-26) 2403 2404- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2405 2406- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2407 2408- CFG_SCCR: System Clock and reset Control Register (15-27) 2409 2410- CFG_OR_TIMING_SDRAM: 2411 SDRAM timing 2412 2413- CFG_MAMR_PTA: 2414 periodic timer for refresh 2415 2416- CFG_DER: Debug Event Register (37-47) 2417 2418- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2419 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2420 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2421 CFG_BR1_PRELIM: 2422 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2423 2424- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2425 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2426 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2427 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2428 2429- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2430 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2431 Machine Mode Register and Memory Periodic Timer 2432 Prescaler definitions (SDRAM timing) 2433 2434- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2435 enable I2C microcode relocation patch (MPC8xx); 2436 define relocation offset in DPRAM [DSP2] 2437 2438- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]: 2439 enable SMC microcode relocation patch (MPC8xx); 2440 define relocation offset in DPRAM [SMC1] 2441 2442- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2443 enable SPI microcode relocation patch (MPC8xx); 2444 define relocation offset in DPRAM [SCC4] 2445 2446- CFG_USE_OSCCLK: 2447 Use OSCM clock mode on MBX8xx board. Be careful, 2448 wrong setting might damage your board. Read 2449 doc/README.MBX before setting this variable! 2450 2451- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2452 Offset of the bootmode word in DPRAM used by post 2453 (Power On Self Tests). This definition overrides 2454 #define'd default value in commproc.h resp. 2455 cpm_8260.h. 2456 2457- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2458 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2459 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2460 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2461 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2462 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2463 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2464 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2465 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2466 2467- CONFIG_SPD_EEPROM 2468 Get DDR timing information from an I2C EEPROM. Common 2469 with pluggable memory modules such as SODIMMs 2470 2471 SPD_EEPROM_ADDRESS 2472 I2C address of the SPD EEPROM 2473 2474- CFG_SPD_BUS_NUM 2475 If SPD EEPROM is on an I2C bus other than the first 2476 one, specify here. Note that the value must resolve 2477 to something your driver can deal with. 2478 2479- CFG_83XX_DDR_USES_CS0 2480 Only for 83xx systems. If specified, then DDR should 2481 be configured using CS0 and CS1 instead of CS2 and CS3. 2482 2483- CFG_83XX_DDR_USES_CS0 2484 Only for 83xx systems. If specified, then DDR should 2485 be configured using CS0 and CS1 instead of CS2 and CS3. 2486 2487- CONFIG_ETHER_ON_FEC[12] 2488 Define to enable FEC[12] on a 8xx series processor. 2489 2490- CONFIG_FEC[12]_PHY 2491 Define to the hardcoded PHY address which corresponds 2492 to the given FEC; i. e. 2493 #define CONFIG_FEC1_PHY 4 2494 means that the PHY with address 4 is connected to FEC1 2495 2496 When set to -1, means to probe for first available. 2497 2498- CONFIG_FEC[12]_PHY_NORXERR 2499 The PHY does not have a RXERR line (RMII only). 2500 (so program the FEC to ignore it). 2501 2502- CONFIG_RMII 2503 Enable RMII mode for all FECs. 2504 Note that this is a global option, we can't 2505 have one FEC in standard MII mode and another in RMII mode. 2506 2507- CONFIG_CRC32_VERIFY 2508 Add a verify option to the crc32 command. 2509 The syntax is: 2510 2511 => crc32 -v <address> <count> <crc32> 2512 2513 Where address/count indicate a memory area 2514 and crc32 is the correct crc32 which the 2515 area should have. 2516 2517- CONFIG_LOOPW 2518 Add the "loopw" memory command. This only takes effect if 2519 the memory commands are activated globally (CONFIG_CMD_MEM). 2520 2521- CONFIG_MX_CYCLIC 2522 Add the "mdc" and "mwc" memory commands. These are cyclic 2523 "md/mw" commands. 2524 Examples: 2525 2526 => mdc.b 10 4 500 2527 This command will print 4 bytes (10,11,12,13) each 500 ms. 2528 2529 => mwc.l 100 12345678 10 2530 This command will write 12345678 to address 100 all 10 ms. 2531 2532 This only takes effect if the memory commands are activated 2533 globally (CONFIG_CMD_MEM). 2534 2535- CONFIG_SKIP_LOWLEVEL_INIT 2536- CONFIG_SKIP_RELOCATE_UBOOT 2537 2538 [ARM only] If these variables are defined, then 2539 certain low level initializations (like setting up 2540 the memory controller) are omitted and/or U-Boot does 2541 not relocate itself into RAM. 2542 Normally these variables MUST NOT be defined. The 2543 only exception is when U-Boot is loaded (to RAM) by 2544 some other boot loader or by a debugger which 2545 performs these initializations itself. 2546 2547 2548Building the Software: 2549====================== 2550 2551Building U-Boot has been tested in several native build environments 2552and in many different cross environments. Of course we cannot support 2553all possibly existing versions of cross development tools in all 2554(potentially obsolete) versions. In case of tool chain problems we 2555recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 2556which is extensively used to build and test U-Boot. 2557 2558If you are not using a native environment, it is assumed that you 2559have GNU cross compiling tools available in your path. In this case, 2560you must set the environment variable CROSS_COMPILE in your shell. 2561Note that no changes to the Makefile or any other source files are 2562necessary. For example using the ELDK on a 4xx CPU, please enter: 2563 2564 $ CROSS_COMPILE=ppc_4xx- 2565 $ export CROSS_COMPILE 2566 2567U-Boot is intended to be simple to build. After installing the 2568sources you must configure U-Boot for one specific board type. This 2569is done by typing: 2570 2571 make NAME_config 2572 2573where "NAME_config" is the name of one of the existing configu- 2574rations; see the main Makefile for supported names. 2575 2576Note: for some board special configuration names may exist; check if 2577 additional information is available from the board vendor; for 2578 instance, the TQM823L systems are available without (standard) 2579 or with LCD support. You can select such additional "features" 2580 when choosing the configuration, i. e. 2581 2582 make TQM823L_config 2583 - will configure for a plain TQM823L, i. e. no LCD support 2584 2585 make TQM823L_LCD_config 2586 - will configure for a TQM823L with U-Boot console on LCD 2587 2588 etc. 2589 2590 2591Finally, type "make all", and you should get some working U-Boot 2592images ready for download to / installation on your system: 2593 2594- "u-boot.bin" is a raw binary image 2595- "u-boot" is an image in ELF binary format 2596- "u-boot.srec" is in Motorola S-Record format 2597 2598By default the build is performed locally and the objects are saved 2599in the source directory. One of the two methods can be used to change 2600this behavior and build U-Boot to some external directory: 2601 26021. Add O= to the make command line invocations: 2603 2604 make O=/tmp/build distclean 2605 make O=/tmp/build NAME_config 2606 make O=/tmp/build all 2607 26082. Set environment variable BUILD_DIR to point to the desired location: 2609 2610 export BUILD_DIR=/tmp/build 2611 make distclean 2612 make NAME_config 2613 make all 2614 2615Note that the command line "O=" setting overrides the BUILD_DIR environment 2616variable. 2617 2618 2619Please be aware that the Makefiles assume you are using GNU make, so 2620for instance on NetBSD you might need to use "gmake" instead of 2621native "make". 2622 2623 2624If the system board that you have is not listed, then you will need 2625to port U-Boot to your hardware platform. To do this, follow these 2626steps: 2627 26281. Add a new configuration option for your board to the toplevel 2629 "Makefile" and to the "MAKEALL" script, using the existing 2630 entries as examples. Note that here and at many other places 2631 boards and other names are listed in alphabetical sort order. Please 2632 keep this order. 26332. Create a new directory to hold your board specific code. Add any 2634 files you need. In your board directory, you will need at least 2635 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 26363. Create a new configuration file "include/configs/<board>.h" for 2637 your board 26383. If you're porting U-Boot to a new CPU, then also create a new 2639 directory to hold your CPU specific code. Add any files you need. 26404. Run "make <board>_config" with your new name. 26415. Type "make", and you should get a working "u-boot.srec" file 2642 to be installed on your target system. 26436. Debug and solve any problems that might arise. 2644 [Of course, this last step is much harder than it sounds.] 2645 2646 2647Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2648============================================================== 2649 2650If you have modified U-Boot sources (for instance added a new board 2651or support for new devices, a new CPU, etc.) you are expected to 2652provide feedback to the other developers. The feedback normally takes 2653the form of a "patch", i. e. a context diff against a certain (latest 2654official or latest in the git repository) version of U-Boot sources. 2655 2656But before you submit such a patch, please verify that your modifi- 2657cation did not break existing code. At least make sure that *ALL* of 2658the supported boards compile WITHOUT ANY compiler warnings. To do so, 2659just run the "MAKEALL" script, which will configure and build U-Boot 2660for ALL supported system. Be warned, this will take a while. You can 2661select which (cross) compiler to use by passing a `CROSS_COMPILE' 2662environment variable to the script, i. e. to use the ELDK cross tools 2663you can type 2664 2665 CROSS_COMPILE=ppc_8xx- MAKEALL 2666 2667or to build on a native PowerPC system you can type 2668 2669 CROSS_COMPILE=' ' MAKEALL 2670 2671When using the MAKEALL script, the default behaviour is to build 2672U-Boot in the source directory. This location can be changed by 2673setting the BUILD_DIR environment variable. Also, for each target 2674built, the MAKEALL script saves two log files (<target>.ERR and 2675<target>.MAKEALL) in the <source dir>/LOG directory. This default 2676location can be changed by setting the MAKEALL_LOGDIR environment 2677variable. For example: 2678 2679 export BUILD_DIR=/tmp/build 2680 export MAKEALL_LOGDIR=/tmp/log 2681 CROSS_COMPILE=ppc_8xx- MAKEALL 2682 2683With the above settings build objects are saved in the /tmp/build, 2684log files are saved in the /tmp/log and the source tree remains clean 2685during the whole build process. 2686 2687 2688See also "U-Boot Porting Guide" below. 2689 2690 2691Monitor Commands - Overview: 2692============================ 2693 2694go - start application at address 'addr' 2695run - run commands in an environment variable 2696bootm - boot application image from memory 2697bootp - boot image via network using BootP/TFTP protocol 2698tftpboot- boot image via network using TFTP protocol 2699 and env variables "ipaddr" and "serverip" 2700 (and eventually "gatewayip") 2701rarpboot- boot image via network using RARP/TFTP protocol 2702diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2703loads - load S-Record file over serial line 2704loadb - load binary file over serial line (kermit mode) 2705md - memory display 2706mm - memory modify (auto-incrementing) 2707nm - memory modify (constant address) 2708mw - memory write (fill) 2709cp - memory copy 2710cmp - memory compare 2711crc32 - checksum calculation 2712imd - i2c memory display 2713imm - i2c memory modify (auto-incrementing) 2714inm - i2c memory modify (constant address) 2715imw - i2c memory write (fill) 2716icrc32 - i2c checksum calculation 2717iprobe - probe to discover valid I2C chip addresses 2718iloop - infinite loop on address range 2719isdram - print SDRAM configuration information 2720sspi - SPI utility commands 2721base - print or set address offset 2722printenv- print environment variables 2723setenv - set environment variables 2724saveenv - save environment variables to persistent storage 2725protect - enable or disable FLASH write protection 2726erase - erase FLASH memory 2727flinfo - print FLASH memory information 2728bdinfo - print Board Info structure 2729iminfo - print header information for application image 2730coninfo - print console devices and informations 2731ide - IDE sub-system 2732loop - infinite loop on address range 2733loopw - infinite write loop on address range 2734mtest - simple RAM test 2735icache - enable or disable instruction cache 2736dcache - enable or disable data cache 2737reset - Perform RESET of the CPU 2738echo - echo args to console 2739version - print monitor version 2740help - print online help 2741? - alias for 'help' 2742 2743 2744Monitor Commands - Detailed Description: 2745======================================== 2746 2747TODO. 2748 2749For now: just type "help <command>". 2750 2751 2752Environment Variables: 2753====================== 2754 2755U-Boot supports user configuration using Environment Variables which 2756can be made persistent by saving to Flash memory. 2757 2758Environment Variables are set using "setenv", printed using 2759"printenv", and saved to Flash using "saveenv". Using "setenv" 2760without a value can be used to delete a variable from the 2761environment. As long as you don't save the environment you are 2762working with an in-memory copy. In case the Flash area containing the 2763environment is erased by accident, a default environment is provided. 2764 2765Some configuration options can be set using Environment Variables: 2766 2767 baudrate - see CONFIG_BAUDRATE 2768 2769 bootdelay - see CONFIG_BOOTDELAY 2770 2771 bootcmd - see CONFIG_BOOTCOMMAND 2772 2773 bootargs - Boot arguments when booting an RTOS image 2774 2775 bootfile - Name of the image to load with TFTP 2776 2777 bootm_low - Memory range available for image processing in the bootm 2778 command can be restricted. This variable is given as 2779 a hexadecimal number and defines lowest address allowed 2780 for use by the bootm command. See also "bootm_size" 2781 environment variable. Address defined by "bootm_low" is 2782 also the base of the initial memory mapping for the Linux 2783 kernel -- see the description of CFG_BOOTMAPSZ. 2784 2785 bootm_size - Memory range available for image processing in the bootm 2786 command can be restricted. This variable is given as 2787 a hexadecimal number and defines the size of the region 2788 allowed for use by the bootm command. See also "bootm_low" 2789 environment variable. 2790 2791 autoload - if set to "no" (any string beginning with 'n'), 2792 "bootp" will just load perform a lookup of the 2793 configuration from the BOOTP server, but not try to 2794 load any image using TFTP 2795 2796 autoscript - if set to "yes" commands like "loadb", "loady", 2797 "bootp", "tftpb", "rarpboot" and "nfs" will attempt 2798 to automatically run script images (by internally 2799 calling "autoscript"). 2800 2801 autoscript_uname - if script image is in a format (FIT) this 2802 variable is used to get script subimage unit name. 2803 2804 autostart - if set to "yes", an image loaded using the "bootp", 2805 "rarpboot", "tftpboot" or "diskboot" commands will 2806 be automatically started (by internally calling 2807 "bootm") 2808 2809 If set to "no", a standalone image passed to the 2810 "bootm" command will be copied to the load address 2811 (and eventually uncompressed), but NOT be started. 2812 This can be used to load and uncompress arbitrary 2813 data. 2814 2815 i2cfast - (PPC405GP|PPC405EP only) 2816 if set to 'y' configures Linux I2C driver for fast 2817 mode (400kHZ). This environment variable is used in 2818 initialization code. So, for changes to be effective 2819 it must be saved and board must be reset. 2820 2821 initrd_high - restrict positioning of initrd images: 2822 If this variable is not set, initrd images will be 2823 copied to the highest possible address in RAM; this 2824 is usually what you want since it allows for 2825 maximum initrd size. If for some reason you want to 2826 make sure that the initrd image is loaded below the 2827 CFG_BOOTMAPSZ limit, you can set this environment 2828 variable to a value of "no" or "off" or "0". 2829 Alternatively, you can set it to a maximum upper 2830 address to use (U-Boot will still check that it 2831 does not overwrite the U-Boot stack and data). 2832 2833 For instance, when you have a system with 16 MB 2834 RAM, and want to reserve 4 MB from use by Linux, 2835 you can do this by adding "mem=12M" to the value of 2836 the "bootargs" variable. However, now you must make 2837 sure that the initrd image is placed in the first 2838 12 MB as well - this can be done with 2839 2840 setenv initrd_high 00c00000 2841 2842 If you set initrd_high to 0xFFFFFFFF, this is an 2843 indication to U-Boot that all addresses are legal 2844 for the Linux kernel, including addresses in flash 2845 memory. In this case U-Boot will NOT COPY the 2846 ramdisk at all. This may be useful to reduce the 2847 boot time on your system, but requires that this 2848 feature is supported by your Linux kernel. 2849 2850 ipaddr - IP address; needed for tftpboot command 2851 2852 loadaddr - Default load address for commands like "bootp", 2853 "rarpboot", "tftpboot", "loadb" or "diskboot" 2854 2855 loads_echo - see CONFIG_LOADS_ECHO 2856 2857 serverip - TFTP server IP address; needed for tftpboot command 2858 2859 bootretry - see CONFIG_BOOT_RETRY_TIME 2860 2861 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2862 2863 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2864 2865 ethprime - When CONFIG_NET_MULTI is enabled controls which 2866 interface is used first. 2867 2868 ethact - When CONFIG_NET_MULTI is enabled controls which 2869 interface is currently active. For example you 2870 can do the following 2871 2872 => setenv ethact FEC ETHERNET 2873 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2874 => setenv ethact SCC ETHERNET 2875 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2876 2877 ethrotate - When set to "no" U-Boot does not go through all 2878 available network interfaces. 2879 It just stays at the currently selected interface. 2880 2881 netretry - When set to "no" each network operation will 2882 either succeed or fail without retrying. 2883 When set to "once" the network operation will 2884 fail when all the available network interfaces 2885 are tried once without success. 2886 Useful on scripts which control the retry operation 2887 themselves. 2888 2889 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD 2890 if set load address for the NPE microcode 2891 2892 tftpsrcport - If this is set, the value is used for TFTP's 2893 UDP source port. 2894 2895 tftpdstport - If this is set, the value is used for TFTP's UDP 2896 destination port instead of the Well Know Port 69. 2897 2898 vlan - When set to a value < 4095 the traffic over 2899 Ethernet is encapsulated/received over 802.1q 2900 VLAN tagged frames. 2901 2902The following environment variables may be used and automatically 2903updated by the network boot commands ("bootp" and "rarpboot"), 2904depending the information provided by your boot server: 2905 2906 bootfile - see above 2907 dnsip - IP address of your Domain Name Server 2908 dnsip2 - IP address of your secondary Domain Name Server 2909 gatewayip - IP address of the Gateway (Router) to use 2910 hostname - Target hostname 2911 ipaddr - see above 2912 netmask - Subnet Mask 2913 rootpath - Pathname of the root filesystem on the NFS server 2914 serverip - see above 2915 2916 2917There are two special Environment Variables: 2918 2919 serial# - contains hardware identification information such 2920 as type string and/or serial number 2921 ethaddr - Ethernet address 2922 2923These variables can be set only once (usually during manufacturing of 2924the board). U-Boot refuses to delete or overwrite these variables 2925once they have been set once. 2926 2927 2928Further special Environment Variables: 2929 2930 ver - Contains the U-Boot version string as printed 2931 with the "version" command. This variable is 2932 readonly (see CONFIG_VERSION_VARIABLE). 2933 2934 2935Please note that changes to some configuration parameters may take 2936only effect after the next boot (yes, that's just like Windoze :-). 2937 2938 2939Command Line Parsing: 2940===================== 2941 2942There are two different command line parsers available with U-Boot: 2943the old "simple" one, and the much more powerful "hush" shell: 2944 2945Old, simple command line parser: 2946-------------------------------- 2947 2948- supports environment variables (through setenv / saveenv commands) 2949- several commands on one line, separated by ';' 2950- variable substitution using "... ${name} ..." syntax 2951- special characters ('$', ';') can be escaped by prefixing with '\', 2952 for example: 2953 setenv bootcmd bootm \${address} 2954- You can also escape text by enclosing in single apostrophes, for example: 2955 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2956 2957Hush shell: 2958----------- 2959 2960- similar to Bourne shell, with control structures like 2961 if...then...else...fi, for...do...done; while...do...done, 2962 until...do...done, ... 2963- supports environment ("global") variables (through setenv / saveenv 2964 commands) and local shell variables (through standard shell syntax 2965 "name=value"); only environment variables can be used with "run" 2966 command 2967 2968General rules: 2969-------------- 2970 2971(1) If a command line (or an environment variable executed by a "run" 2972 command) contains several commands separated by semicolon, and 2973 one of these commands fails, then the remaining commands will be 2974 executed anyway. 2975 2976(2) If you execute several variables with one call to run (i. e. 2977 calling run with a list of variables as arguments), any failing 2978 command will cause "run" to terminate, i. e. the remaining 2979 variables are not executed. 2980 2981Note for Redundant Ethernet Interfaces: 2982======================================= 2983 2984Some boards come with redundant Ethernet interfaces; U-Boot supports 2985such configurations and is capable of automatic selection of a 2986"working" interface when needed. MAC assignment works as follows: 2987 2988Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2989MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2990"eth1addr" (=>eth1), "eth2addr", ... 2991 2992If the network interface stores some valid MAC address (for instance 2993in SROM), this is used as default address if there is NO correspon- 2994ding setting in the environment; if the corresponding environment 2995variable is set, this overrides the settings in the card; that means: 2996 2997o If the SROM has a valid MAC address, and there is no address in the 2998 environment, the SROM's address is used. 2999 3000o If there is no valid address in the SROM, and a definition in the 3001 environment exists, then the value from the environment variable is 3002 used. 3003 3004o If both the SROM and the environment contain a MAC address, and 3005 both addresses are the same, this MAC address is used. 3006 3007o If both the SROM and the environment contain a MAC address, and the 3008 addresses differ, the value from the environment is used and a 3009 warning is printed. 3010 3011o If neither SROM nor the environment contain a MAC address, an error 3012 is raised. 3013 3014 3015Image Formats: 3016============== 3017 3018U-Boot is capable of booting (and performing other auxiliary operations on) 3019images in two formats: 3020 3021New uImage format (FIT) 3022----------------------- 3023 3024Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3025to Flattened Device Tree). It allows the use of images with multiple 3026components (several kernels, ramdisks, etc.), with contents protected by 3027SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3028 3029 3030Old uImage format 3031----------------- 3032 3033Old image format is based on binary files which can be basically anything, 3034preceded by a special header; see the definitions in include/image.h for 3035details; basically, the header defines the following image properties: 3036 3037* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3038 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3039 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 3040 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 3041 INTEGRITY). 3042* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3043 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3044 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 3045* Compression Type (uncompressed, gzip, bzip2) 3046* Load Address 3047* Entry Point 3048* Image Name 3049* Image Timestamp 3050 3051The header is marked by a special Magic Number, and both the header 3052and the data portions of the image are secured against corruption by 3053CRC32 checksums. 3054 3055 3056Linux Support: 3057============== 3058 3059Although U-Boot should support any OS or standalone application 3060easily, the main focus has always been on Linux during the design of 3061U-Boot. 3062 3063U-Boot includes many features that so far have been part of some 3064special "boot loader" code within the Linux kernel. Also, any 3065"initrd" images to be used are no longer part of one big Linux image; 3066instead, kernel and "initrd" are separate images. This implementation 3067serves several purposes: 3068 3069- the same features can be used for other OS or standalone 3070 applications (for instance: using compressed images to reduce the 3071 Flash memory footprint) 3072 3073- it becomes much easier to port new Linux kernel versions because 3074 lots of low-level, hardware dependent stuff are done by U-Boot 3075 3076- the same Linux kernel image can now be used with different "initrd" 3077 images; of course this also means that different kernel images can 3078 be run with the same "initrd". This makes testing easier (you don't 3079 have to build a new "zImage.initrd" Linux image when you just 3080 change a file in your "initrd"). Also, a field-upgrade of the 3081 software is easier now. 3082 3083 3084Linux HOWTO: 3085============ 3086 3087Porting Linux to U-Boot based systems: 3088--------------------------------------- 3089 3090U-Boot cannot save you from doing all the necessary modifications to 3091configure the Linux device drivers for use with your target hardware 3092(no, we don't intend to provide a full virtual machine interface to 3093Linux :-). 3094 3095But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 3096 3097Just make sure your machine specific header file (for instance 3098include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3099Information structure as we define in include/asm-<arch>/u-boot.h, 3100and make sure that your definition of IMAP_ADDR uses the same value 3101as your U-Boot configuration in CFG_IMMR. 3102 3103 3104Configuring the Linux kernel: 3105----------------------------- 3106 3107No specific requirements for U-Boot. Make sure you have some root 3108device (initial ramdisk, NFS) for your target system. 3109 3110 3111Building a Linux Image: 3112----------------------- 3113 3114With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3115not used. If you use recent kernel source, a new build target 3116"uImage" will exist which automatically builds an image usable by 3117U-Boot. Most older kernels also have support for a "pImage" target, 3118which was introduced for our predecessor project PPCBoot and uses a 3119100% compatible format. 3120 3121Example: 3122 3123 make TQM850L_config 3124 make oldconfig 3125 make dep 3126 make uImage 3127 3128The "uImage" build target uses a special tool (in 'tools/mkimage') to 3129encapsulate a compressed Linux kernel image with header information, 3130CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3131 3132* build a standard "vmlinux" kernel image (in ELF binary format): 3133 3134* convert the kernel into a raw binary image: 3135 3136 ${CROSS_COMPILE}-objcopy -O binary \ 3137 -R .note -R .comment \ 3138 -S vmlinux linux.bin 3139 3140* compress the binary image: 3141 3142 gzip -9 linux.bin 3143 3144* package compressed binary image for U-Boot: 3145 3146 mkimage -A ppc -O linux -T kernel -C gzip \ 3147 -a 0 -e 0 -n "Linux Kernel Image" \ 3148 -d linux.bin.gz uImage 3149 3150 3151The "mkimage" tool can also be used to create ramdisk images for use 3152with U-Boot, either separated from the Linux kernel image, or 3153combined into one file. "mkimage" encapsulates the images with a 64 3154byte header containing information about target architecture, 3155operating system, image type, compression method, entry points, time 3156stamp, CRC32 checksums, etc. 3157 3158"mkimage" can be called in two ways: to verify existing images and 3159print the header information, or to build new images. 3160 3161In the first form (with "-l" option) mkimage lists the information 3162contained in the header of an existing U-Boot image; this includes 3163checksum verification: 3164 3165 tools/mkimage -l image 3166 -l ==> list image header information 3167 3168The second form (with "-d" option) is used to build a U-Boot image 3169from a "data file" which is used as image payload: 3170 3171 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3172 -n name -d data_file image 3173 -A ==> set architecture to 'arch' 3174 -O ==> set operating system to 'os' 3175 -T ==> set image type to 'type' 3176 -C ==> set compression type 'comp' 3177 -a ==> set load address to 'addr' (hex) 3178 -e ==> set entry point to 'ep' (hex) 3179 -n ==> set image name to 'name' 3180 -d ==> use image data from 'datafile' 3181 3182Right now, all Linux kernels for PowerPC systems use the same load 3183address (0x00000000), but the entry point address depends on the 3184kernel version: 3185 3186- 2.2.x kernels have the entry point at 0x0000000C, 3187- 2.3.x and later kernels have the entry point at 0x00000000. 3188 3189So a typical call to build a U-Boot image would read: 3190 3191 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3192 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3193 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 3194 > examples/uImage.TQM850L 3195 Image Name: 2.4.4 kernel for TQM850L 3196 Created: Wed Jul 19 02:34:59 2000 3197 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3198 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3199 Load Address: 0x00000000 3200 Entry Point: 0x00000000 3201 3202To verify the contents of the image (or check for corruption): 3203 3204 -> tools/mkimage -l examples/uImage.TQM850L 3205 Image Name: 2.4.4 kernel for TQM850L 3206 Created: Wed Jul 19 02:34:59 2000 3207 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3208 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3209 Load Address: 0x00000000 3210 Entry Point: 0x00000000 3211 3212NOTE: for embedded systems where boot time is critical you can trade 3213speed for memory and install an UNCOMPRESSED image instead: this 3214needs more space in Flash, but boots much faster since it does not 3215need to be uncompressed: 3216 3217 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3218 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3219 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3220 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3221 > examples/uImage.TQM850L-uncompressed 3222 Image Name: 2.4.4 kernel for TQM850L 3223 Created: Wed Jul 19 02:34:59 2000 3224 Image Type: PowerPC Linux Kernel Image (uncompressed) 3225 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3226 Load Address: 0x00000000 3227 Entry Point: 0x00000000 3228 3229 3230Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3231when your kernel is intended to use an initial ramdisk: 3232 3233 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3234 > -A ppc -O linux -T ramdisk -C gzip \ 3235 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3236 Image Name: Simple Ramdisk Image 3237 Created: Wed Jan 12 14:01:50 2000 3238 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3239 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3240 Load Address: 0x00000000 3241 Entry Point: 0x00000000 3242 3243 3244Installing a Linux Image: 3245------------------------- 3246 3247To downloading a U-Boot image over the serial (console) interface, 3248you must convert the image to S-Record format: 3249 3250 objcopy -I binary -O srec examples/image examples/image.srec 3251 3252The 'objcopy' does not understand the information in the U-Boot 3253image header, so the resulting S-Record file will be relative to 3254address 0x00000000. To load it to a given address, you need to 3255specify the target address as 'offset' parameter with the 'loads' 3256command. 3257 3258Example: install the image to address 0x40100000 (which on the 3259TQM8xxL is in the first Flash bank): 3260 3261 => erase 40100000 401FFFFF 3262 3263 .......... done 3264 Erased 8 sectors 3265 3266 => loads 40100000 3267 ## Ready for S-Record download ... 3268 ~>examples/image.srec 3269 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3270 ... 3271 15989 15990 15991 15992 3272 [file transfer complete] 3273 [connected] 3274 ## Start Addr = 0x00000000 3275 3276 3277You can check the success of the download using the 'iminfo' command; 3278this includes a checksum verification so you can be sure no data 3279corruption happened: 3280 3281 => imi 40100000 3282 3283 ## Checking Image at 40100000 ... 3284 Image Name: 2.2.13 for initrd on TQM850L 3285 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3286 Data Size: 335725 Bytes = 327 kB = 0 MB 3287 Load Address: 00000000 3288 Entry Point: 0000000c 3289 Verifying Checksum ... OK 3290 3291 3292Boot Linux: 3293----------- 3294 3295The "bootm" command is used to boot an application that is stored in 3296memory (RAM or Flash). In case of a Linux kernel image, the contents 3297of the "bootargs" environment variable is passed to the kernel as 3298parameters. You can check and modify this variable using the 3299"printenv" and "setenv" commands: 3300 3301 3302 => printenv bootargs 3303 bootargs=root=/dev/ram 3304 3305 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3306 3307 => printenv bootargs 3308 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3309 3310 => bootm 40020000 3311 ## Booting Linux kernel at 40020000 ... 3312 Image Name: 2.2.13 for NFS on TQM850L 3313 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3314 Data Size: 381681 Bytes = 372 kB = 0 MB 3315 Load Address: 00000000 3316 Entry Point: 0000000c 3317 Verifying Checksum ... OK 3318 Uncompressing Kernel Image ... OK 3319 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 3320 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3321 time_init: decrementer frequency = 187500000/60 3322 Calibrating delay loop... 49.77 BogoMIPS 3323 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3324 ... 3325 3326If you want to boot a Linux kernel with initial RAM disk, you pass 3327the memory addresses of both the kernel and the initrd image (PPBCOOT 3328format!) to the "bootm" command: 3329 3330 => imi 40100000 40200000 3331 3332 ## Checking Image at 40100000 ... 3333 Image Name: 2.2.13 for initrd on TQM850L 3334 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3335 Data Size: 335725 Bytes = 327 kB = 0 MB 3336 Load Address: 00000000 3337 Entry Point: 0000000c 3338 Verifying Checksum ... OK 3339 3340 ## Checking Image at 40200000 ... 3341 Image Name: Simple Ramdisk Image 3342 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3343 Data Size: 566530 Bytes = 553 kB = 0 MB 3344 Load Address: 00000000 3345 Entry Point: 00000000 3346 Verifying Checksum ... OK 3347 3348 => bootm 40100000 40200000 3349 ## Booting Linux kernel at 40100000 ... 3350 Image Name: 2.2.13 for initrd on TQM850L 3351 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3352 Data Size: 335725 Bytes = 327 kB = 0 MB 3353 Load Address: 00000000 3354 Entry Point: 0000000c 3355 Verifying Checksum ... OK 3356 Uncompressing Kernel Image ... OK 3357 ## Loading RAMDisk Image at 40200000 ... 3358 Image Name: Simple Ramdisk Image 3359 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3360 Data Size: 566530 Bytes = 553 kB = 0 MB 3361 Load Address: 00000000 3362 Entry Point: 00000000 3363 Verifying Checksum ... OK 3364 Loading Ramdisk ... OK 3365 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 3366 Boot arguments: root=/dev/ram 3367 time_init: decrementer frequency = 187500000/60 3368 Calibrating delay loop... 49.77 BogoMIPS 3369 ... 3370 RAMDISK: Compressed image found at block 0 3371 VFS: Mounted root (ext2 filesystem). 3372 3373 bash# 3374 3375Boot Linux and pass a flat device tree: 3376----------- 3377 3378First, U-Boot must be compiled with the appropriate defines. See the section 3379titled "Linux Kernel Interface" above for a more in depth explanation. The 3380following is an example of how to start a kernel and pass an updated 3381flat device tree: 3382 3383=> print oftaddr 3384oftaddr=0x300000 3385=> print oft 3386oft=oftrees/mpc8540ads.dtb 3387=> tftp $oftaddr $oft 3388Speed: 1000, full duplex 3389Using TSEC0 device 3390TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3391Filename 'oftrees/mpc8540ads.dtb'. 3392Load address: 0x300000 3393Loading: # 3394done 3395Bytes transferred = 4106 (100a hex) 3396=> tftp $loadaddr $bootfile 3397Speed: 1000, full duplex 3398Using TSEC0 device 3399TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3400Filename 'uImage'. 3401Load address: 0x200000 3402Loading:############ 3403done 3404Bytes transferred = 1029407 (fb51f hex) 3405=> print loadaddr 3406loadaddr=200000 3407=> print oftaddr 3408oftaddr=0x300000 3409=> bootm $loadaddr - $oftaddr 3410## Booting image at 00200000 ... 3411 Image Name: Linux-2.6.17-dirty 3412 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3413 Data Size: 1029343 Bytes = 1005.2 kB 3414 Load Address: 00000000 3415 Entry Point: 00000000 3416 Verifying Checksum ... OK 3417 Uncompressing Kernel Image ... OK 3418Booting using flat device tree at 0x300000 3419Using MPC85xx ADS machine description 3420Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3421[snip] 3422 3423 3424More About U-Boot Image Types: 3425------------------------------ 3426 3427U-Boot supports the following image types: 3428 3429 "Standalone Programs" are directly runnable in the environment 3430 provided by U-Boot; it is expected that (if they behave 3431 well) you can continue to work in U-Boot after return from 3432 the Standalone Program. 3433 "OS Kernel Images" are usually images of some Embedded OS which 3434 will take over control completely. Usually these programs 3435 will install their own set of exception handlers, device 3436 drivers, set up the MMU, etc. - this means, that you cannot 3437 expect to re-enter U-Boot except by resetting the CPU. 3438 "RAMDisk Images" are more or less just data blocks, and their 3439 parameters (address, size) are passed to an OS kernel that is 3440 being started. 3441 "Multi-File Images" contain several images, typically an OS 3442 (Linux) kernel image and one or more data images like 3443 RAMDisks. This construct is useful for instance when you want 3444 to boot over the network using BOOTP etc., where the boot 3445 server provides just a single image file, but you want to get 3446 for instance an OS kernel and a RAMDisk image. 3447 3448 "Multi-File Images" start with a list of image sizes, each 3449 image size (in bytes) specified by an "uint32_t" in network 3450 byte order. This list is terminated by an "(uint32_t)0". 3451 Immediately after the terminating 0 follow the images, one by 3452 one, all aligned on "uint32_t" boundaries (size rounded up to 3453 a multiple of 4 bytes). 3454 3455 "Firmware Images" are binary images containing firmware (like 3456 U-Boot or FPGA images) which usually will be programmed to 3457 flash memory. 3458 3459 "Script files" are command sequences that will be executed by 3460 U-Boot's command interpreter; this feature is especially 3461 useful when you configure U-Boot to use a real shell (hush) 3462 as command interpreter. 3463 3464 3465Standalone HOWTO: 3466================= 3467 3468One of the features of U-Boot is that you can dynamically load and 3469run "standalone" applications, which can use some resources of 3470U-Boot like console I/O functions or interrupt services. 3471 3472Two simple examples are included with the sources: 3473 3474"Hello World" Demo: 3475------------------- 3476 3477'examples/hello_world.c' contains a small "Hello World" Demo 3478application; it is automatically compiled when you build U-Boot. 3479It's configured to run at address 0x00040004, so you can play with it 3480like that: 3481 3482 => loads 3483 ## Ready for S-Record download ... 3484 ~>examples/hello_world.srec 3485 1 2 3 4 5 6 7 8 9 10 11 ... 3486 [file transfer complete] 3487 [connected] 3488 ## Start Addr = 0x00040004 3489 3490 => go 40004 Hello World! This is a test. 3491 ## Starting application at 0x00040004 ... 3492 Hello World 3493 argc = 7 3494 argv[0] = "40004" 3495 argv[1] = "Hello" 3496 argv[2] = "World!" 3497 argv[3] = "This" 3498 argv[4] = "is" 3499 argv[5] = "a" 3500 argv[6] = "test." 3501 argv[7] = "<NULL>" 3502 Hit any key to exit ... 3503 3504 ## Application terminated, rc = 0x0 3505 3506Another example, which demonstrates how to register a CPM interrupt 3507handler with the U-Boot code, can be found in 'examples/timer.c'. 3508Here, a CPM timer is set up to generate an interrupt every second. 3509The interrupt service routine is trivial, just printing a '.' 3510character, but this is just a demo program. The application can be 3511controlled by the following keys: 3512 3513 ? - print current values og the CPM Timer registers 3514 b - enable interrupts and start timer 3515 e - stop timer and disable interrupts 3516 q - quit application 3517 3518 => loads 3519 ## Ready for S-Record download ... 3520 ~>examples/timer.srec 3521 1 2 3 4 5 6 7 8 9 10 11 ... 3522 [file transfer complete] 3523 [connected] 3524 ## Start Addr = 0x00040004 3525 3526 => go 40004 3527 ## Starting application at 0x00040004 ... 3528 TIMERS=0xfff00980 3529 Using timer 1 3530 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3531 3532Hit 'b': 3533 [q, b, e, ?] Set interval 1000000 us 3534 Enabling timer 3535Hit '?': 3536 [q, b, e, ?] ........ 3537 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3538Hit '?': 3539 [q, b, e, ?] . 3540 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3541Hit '?': 3542 [q, b, e, ?] . 3543 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3544Hit '?': 3545 [q, b, e, ?] . 3546 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3547Hit 'e': 3548 [q, b, e, ?] ...Stopping timer 3549Hit 'q': 3550 [q, b, e, ?] ## Application terminated, rc = 0x0 3551 3552 3553Minicom warning: 3554================ 3555 3556Over time, many people have reported problems when trying to use the 3557"minicom" terminal emulation program for serial download. I (wd) 3558consider minicom to be broken, and recommend not to use it. Under 3559Unix, I recommend to use C-Kermit for general purpose use (and 3560especially for kermit binary protocol download ("loadb" command), and 3561use "cu" for S-Record download ("loads" command). 3562 3563Nevertheless, if you absolutely want to use it try adding this 3564configuration to your "File transfer protocols" section: 3565 3566 Name Program Name U/D FullScr IO-Red. Multi 3567 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3568 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3569 3570 3571NetBSD Notes: 3572============= 3573 3574Starting at version 0.9.2, U-Boot supports NetBSD both as host 3575(build U-Boot) and target system (boots NetBSD/mpc8xx). 3576 3577Building requires a cross environment; it is known to work on 3578NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3579need gmake since the Makefiles are not compatible with BSD make). 3580Note that the cross-powerpc package does not install include files; 3581attempting to build U-Boot will fail because <machine/ansi.h> is 3582missing. This file has to be installed and patched manually: 3583 3584 # cd /usr/pkg/cross/powerpc-netbsd/include 3585 # mkdir powerpc 3586 # ln -s powerpc machine 3587 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3588 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3589 3590Native builds *don't* work due to incompatibilities between native 3591and U-Boot include files. 3592 3593Booting assumes that (the first part of) the image booted is a 3594stage-2 loader which in turn loads and then invokes the kernel 3595proper. Loader sources will eventually appear in the NetBSD source 3596tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3597meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3598 3599 3600Implementation Internals: 3601========================= 3602 3603The following is not intended to be a complete description of every 3604implementation detail. However, it should help to understand the 3605inner workings of U-Boot and make it easier to port it to custom 3606hardware. 3607 3608 3609Initial Stack, Global Data: 3610--------------------------- 3611 3612The implementation of U-Boot is complicated by the fact that U-Boot 3613starts running out of ROM (flash memory), usually without access to 3614system RAM (because the memory controller is not initialized yet). 3615This means that we don't have writable Data or BSS segments, and BSS 3616is not initialized as zero. To be able to get a C environment working 3617at all, we have to allocate at least a minimal stack. Implementation 3618options for this are defined and restricted by the CPU used: Some CPU 3619models provide on-chip memory (like the IMMR area on MPC8xx and 3620MPC826x processors), on others (parts of) the data cache can be 3621locked as (mis-) used as memory, etc. 3622 3623 Chris Hallinan posted a good summary of these issues to the 3624 u-boot-users mailing list: 3625 3626 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3627 From: "Chris Hallinan" <clh@net1plus.com> 3628 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3629 ... 3630 3631 Correct me if I'm wrong, folks, but the way I understand it 3632 is this: Using DCACHE as initial RAM for Stack, etc, does not 3633 require any physical RAM backing up the cache. The cleverness 3634 is that the cache is being used as a temporary supply of 3635 necessary storage before the SDRAM controller is setup. It's 3636 beyond the scope of this list to explain the details, but you 3637 can see how this works by studying the cache architecture and 3638 operation in the architecture and processor-specific manuals. 3639 3640 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3641 is another option for the system designer to use as an 3642 initial stack/RAM area prior to SDRAM being available. Either 3643 option should work for you. Using CS 4 should be fine if your 3644 board designers haven't used it for something that would 3645 cause you grief during the initial boot! It is frequently not 3646 used. 3647 3648 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3649 with your processor/board/system design. The default value 3650 you will find in any recent u-boot distribution in 3651 walnut.h should work for you. I'd set it to a value larger 3652 than your SDRAM module. If you have a 64MB SDRAM module, set 3653 it above 400_0000. Just make sure your board has no resources 3654 that are supposed to respond to that address! That code in 3655 start.S has been around a while and should work as is when 3656 you get the config right. 3657 3658 -Chris Hallinan 3659 DS4.COM, Inc. 3660 3661It is essential to remember this, since it has some impact on the C 3662code for the initialization procedures: 3663 3664* Initialized global data (data segment) is read-only. Do not attempt 3665 to write it. 3666 3667* Do not use any uninitialized global data (or implicitely initialized 3668 as zero data - BSS segment) at all - this is undefined, initiali- 3669 zation is performed later (when relocating to RAM). 3670 3671* Stack space is very limited. Avoid big data buffers or things like 3672 that. 3673 3674Having only the stack as writable memory limits means we cannot use 3675normal global data to share information beween the code. But it 3676turned out that the implementation of U-Boot can be greatly 3677simplified by making a global data structure (gd_t) available to all 3678functions. We could pass a pointer to this data as argument to _all_ 3679functions, but this would bloat the code. Instead we use a feature of 3680the GCC compiler (Global Register Variables) to share the data: we 3681place a pointer (gd) to the global data into a register which we 3682reserve for this purpose. 3683 3684When choosing a register for such a purpose we are restricted by the 3685relevant (E)ABI specifications for the current architecture, and by 3686GCC's implementation. 3687 3688For PowerPC, the following registers have specific use: 3689 R1: stack pointer 3690 R2: reserved for system use 3691 R3-R4: parameter passing and return values 3692 R5-R10: parameter passing 3693 R13: small data area pointer 3694 R30: GOT pointer 3695 R31: frame pointer 3696 3697 (U-Boot also uses R14 as internal GOT pointer.) 3698 3699 ==> U-Boot will use R2 to hold a pointer to the global data 3700 3701 Note: on PPC, we could use a static initializer (since the 3702 address of the global data structure is known at compile time), 3703 but it turned out that reserving a register results in somewhat 3704 smaller code - although the code savings are not that big (on 3705 average for all boards 752 bytes for the whole U-Boot image, 3706 624 text + 127 data). 3707 3708On Blackfin, the normal C ABI (except for P5) is followed as documented here: 3709 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 3710 3711 ==> U-Boot will use P5 to hold a pointer to the global data 3712 3713On ARM, the following registers are used: 3714 3715 R0: function argument word/integer result 3716 R1-R3: function argument word 3717 R9: GOT pointer 3718 R10: stack limit (used only if stack checking if enabled) 3719 R11: argument (frame) pointer 3720 R12: temporary workspace 3721 R13: stack pointer 3722 R14: link register 3723 R15: program counter 3724 3725 ==> U-Boot will use R8 to hold a pointer to the global data 3726 3727NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3728or current versions of GCC may "optimize" the code too much. 3729 3730Memory Management: 3731------------------ 3732 3733U-Boot runs in system state and uses physical addresses, i.e. the 3734MMU is not used either for address mapping nor for memory protection. 3735 3736The available memory is mapped to fixed addresses using the memory 3737controller. In this process, a contiguous block is formed for each 3738memory type (Flash, SDRAM, SRAM), even when it consists of several 3739physical memory banks. 3740 3741U-Boot is installed in the first 128 kB of the first Flash bank (on 3742TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3743booting and sizing and initializing DRAM, the code relocates itself 3744to the upper end of DRAM. Immediately below the U-Boot code some 3745memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3746configuration setting]. Below that, a structure with global Board 3747Info data is placed, followed by the stack (growing downward). 3748 3749Additionally, some exception handler code is copied to the low 8 kB 3750of DRAM (0x00000000 ... 0x00001FFF). 3751 3752So a typical memory configuration with 16 MB of DRAM could look like 3753this: 3754 3755 0x0000 0000 Exception Vector code 3756 : 3757 0x0000 1FFF 3758 0x0000 2000 Free for Application Use 3759 : 3760 : 3761 3762 : 3763 : 3764 0x00FB FF20 Monitor Stack (Growing downward) 3765 0x00FB FFAC Board Info Data and permanent copy of global data 3766 0x00FC 0000 Malloc Arena 3767 : 3768 0x00FD FFFF 3769 0x00FE 0000 RAM Copy of Monitor Code 3770 ... eventually: LCD or video framebuffer 3771 ... eventually: pRAM (Protected RAM - unchanged by reset) 3772 0x00FF FFFF [End of RAM] 3773 3774 3775System Initialization: 3776---------------------- 3777 3778In the reset configuration, U-Boot starts at the reset entry point 3779(on most PowerPC systems at address 0x00000100). Because of the reset 3780configuration for CS0# this is a mirror of the onboard Flash memory. 3781To be able to re-map memory U-Boot then jumps to its link address. 3782To be able to implement the initialization code in C, a (small!) 3783initial stack is set up in the internal Dual Ported RAM (in case CPUs 3784which provide such a feature like MPC8xx or MPC8260), or in a locked 3785part of the data cache. After that, U-Boot initializes the CPU core, 3786the caches and the SIU. 3787 3788Next, all (potentially) available memory banks are mapped using a 3789preliminary mapping. For example, we put them on 512 MB boundaries 3790(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3791on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3792programmed for SDRAM access. Using the temporary configuration, a 3793simple memory test is run that determines the size of the SDRAM 3794banks. 3795 3796When there is more than one SDRAM bank, and the banks are of 3797different size, the largest is mapped first. For equal size, the first 3798bank (CS2#) is mapped first. The first mapping is always for address 37990x00000000, with any additional banks following immediately to create 3800contiguous memory starting from 0. 3801 3802Then, the monitor installs itself at the upper end of the SDRAM area 3803and allocates memory for use by malloc() and for the global Board 3804Info data; also, the exception vector code is copied to the low RAM 3805pages, and the final stack is set up. 3806 3807Only after this relocation will you have a "normal" C environment; 3808until that you are restricted in several ways, mostly because you are 3809running from ROM, and because the code will have to be relocated to a 3810new address in RAM. 3811 3812 3813U-Boot Porting Guide: 3814---------------------- 3815 3816[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3817list, October 2002] 3818 3819 3820int main (int argc, char *argv[]) 3821{ 3822 sighandler_t no_more_time; 3823 3824 signal (SIGALRM, no_more_time); 3825 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3826 3827 if (available_money > available_manpower) { 3828 pay consultant to port U-Boot; 3829 return 0; 3830 } 3831 3832 Download latest U-Boot source; 3833 3834 Subscribe to u-boot-users mailing list; 3835 3836 if (clueless) { 3837 email ("Hi, I am new to U-Boot, how do I get started?"); 3838 } 3839 3840 while (learning) { 3841 Read the README file in the top level directory; 3842 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3843 Read the source, Luke; 3844 } 3845 3846 if (available_money > toLocalCurrency ($2500)) { 3847 Buy a BDI2000; 3848 } else { 3849 Add a lot of aggravation and time; 3850 } 3851 3852 Create your own board support subdirectory; 3853 3854 Create your own board config file; 3855 3856 while (!running) { 3857 do { 3858 Add / modify source code; 3859 } until (compiles); 3860 Debug; 3861 if (clueless) 3862 email ("Hi, I am having problems..."); 3863 } 3864 Send patch file to Wolfgang; 3865 3866 return 0; 3867} 3868 3869void no_more_time (int sig) 3870{ 3871 hire_a_guru(); 3872} 3873 3874 3875Coding Standards: 3876----------------- 3877 3878All contributions to U-Boot should conform to the Linux kernel 3879coding style; see the file "Documentation/CodingStyle" and the script 3880"scripts/Lindent" in your Linux kernel source directory. In sources 3881originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3882spaces before parameters to function calls) is actually used. 3883 3884Source files originating from a different project (for example the 3885MTD subsystem) are generally exempt from these guidelines and are not 3886reformated to ease subsequent migration to newer versions of those 3887sources. 3888 3889Please note that U-Boot is implemented in C (and to some small parts in 3890Assembler); no C++ is used, so please do not use C++ style comments (//) 3891in your code. 3892 3893Please also stick to the following formatting rules: 3894- remove any trailing white space 3895- use TAB characters for indentation, not spaces 3896- make sure NOT to use DOS '\r\n' line feeds 3897- do not add more than 2 empty lines to source files 3898- do not add trailing empty lines to source files 3899 3900Submissions which do not conform to the standards may be returned 3901with a request to reformat the changes. 3902 3903 3904Submitting Patches: 3905------------------- 3906 3907Since the number of patches for U-Boot is growing, we need to 3908establish some rules. Submissions which do not conform to these rules 3909may be rejected, even when they contain important and valuable stuff. 3910 3911Patches shall be sent to the u-boot-users mailing list. 3912 3913Please see http://www.denx.de/wiki/U-Boot/Patches for details. 3914 3915When you send a patch, please include the following information with 3916it: 3917 3918* For bug fixes: a description of the bug and how your patch fixes 3919 this bug. Please try to include a way of demonstrating that the 3920 patch actually fixes something. 3921 3922* For new features: a description of the feature and your 3923 implementation. 3924 3925* A CHANGELOG entry as plaintext (separate from the patch) 3926 3927* For major contributions, your entry to the CREDITS file 3928 3929* When you add support for a new board, don't forget to add this 3930 board to the MAKEALL script, too. 3931 3932* If your patch adds new configuration options, don't forget to 3933 document these in the README file. 3934 3935* The patch itself. If you are using git (which is *strongly* 3936 recommended) you can easily generate the patch using the 3937 "git-format-patch". If you then use "git-send-email" to send it to 3938 the U-Boot mailing list, you will avoid most of the common problems 3939 with some other mail clients. 3940 3941 If you cannot use git, use "diff -purN OLD NEW". If your version of 3942 diff does not support these options, then get the latest version of 3943 GNU diff. 3944 3945 The current directory when running this command shall be the parent 3946 directory of the U-Boot source tree (i. e. please make sure that 3947 your patch includes sufficient directory information for the 3948 affected files). 3949 3950 We prefer patches as plain text. MIME attachments are discouraged, 3951 and compressed attachments must not be used. 3952 3953* If one logical set of modifications affects or creates several 3954 files, all these changes shall be submitted in a SINGLE patch file. 3955 3956* Changesets that contain different, unrelated modifications shall be 3957 submitted as SEPARATE patches, one patch per changeset. 3958 3959 3960Notes: 3961 3962* Before sending the patch, run the MAKEALL script on your patched 3963 source tree and make sure that no errors or warnings are reported 3964 for any of the boards. 3965 3966* Keep your modifications to the necessary minimum: A patch 3967 containing several unrelated changes or arbitrary reformats will be 3968 returned with a request to re-formatting / split it. 3969 3970* If you modify existing code, make sure that your new code does not 3971 add to the memory footprint of the code ;-) Small is beautiful! 3972 When adding new features, these should compile conditionally only 3973 (using #ifdef), and the resulting code with the new feature 3974 disabled must not need more memory than the old code without your 3975 modification. 3976 3977* Remember that there is a size limit of 40 kB per message on the 3978 u-boot-users mailing list. Bigger patches will be moderated. If 3979 they are reasonable and not bigger than 100 kB, they will be 3980 acknowledged. Even bigger patches should be avoided. 3981