1# 2# (C) Copyright 2000 - 2012 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@lists.denx.de>. There is also an archive of previous traffic 64on the mailing list - please search the archive before asking FAQ's. 65Please see http://lists.denx.de/pipermail/u-boot and 66http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 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 129Starting with the release in October 2008, the names of the releases 130were changed from numerical release numbers without deeper meaning 131into a time stamp based numbering. Regular releases are identified by 132names consisting of the calendar year and month of the release date. 133Additional fields (if present) indicate release candidates or bug fix 134releases in "stable" maintenance trees. 135 136Examples: 137 U-Boot v2009.11 - Release November 2009 138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 140 141 142Directory Hierarchy: 143==================== 144 145/arch Architecture specific files 146 /arm Files generic to ARM architecture 147 /cpu CPU specific files 148 /arm720t Files specific to ARM 720 CPUs 149 /arm920t Files specific to ARM 920 CPUs 150 /at91 Files specific to Atmel AT91RM9200 CPU 151 /imx Files specific to Freescale MC9328 i.MX CPUs 152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 153 /arm925t Files specific to ARM 925 CPUs 154 /arm926ejs Files specific to ARM 926 CPUs 155 /arm1136 Files specific to ARM 1136 CPUs 156 /ixp Files specific to Intel XScale IXP CPUs 157 /pxa Files specific to Intel XScale PXA CPUs 158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs 159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 160 /lib Architecture specific library files 161 /avr32 Files generic to AVR32 architecture 162 /cpu CPU specific files 163 /lib Architecture specific library files 164 /blackfin Files generic to Analog Devices Blackfin architecture 165 /cpu CPU specific files 166 /lib Architecture specific library files 167 /x86 Files generic to x86 architecture 168 /cpu CPU specific files 169 /lib Architecture specific library files 170 /m68k Files generic to m68k architecture 171 /cpu CPU specific files 172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 177 /lib Architecture specific library files 178 /microblaze Files generic to microblaze architecture 179 /cpu CPU specific files 180 /lib Architecture specific library files 181 /mips Files generic to MIPS architecture 182 /cpu CPU specific files 183 /mips32 Files specific to MIPS32 CPUs 184 /xburst Files specific to Ingenic XBurst CPUs 185 /lib Architecture specific library files 186 /nds32 Files generic to NDS32 architecture 187 /cpu CPU specific files 188 /n1213 Files specific to Andes Technology N1213 CPUs 189 /lib Architecture specific library files 190 /nios2 Files generic to Altera NIOS2 architecture 191 /cpu CPU specific files 192 /lib Architecture specific library files 193 /powerpc Files generic to PowerPC architecture 194 /cpu CPU specific files 195 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 196 /mpc5xx Files specific to Freescale MPC5xx CPUs 197 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 198 /mpc8xx Files specific to Freescale MPC8xx CPUs 199 /mpc8220 Files specific to Freescale MPC8220 CPUs 200 /mpc824x Files specific to Freescale MPC824x CPUs 201 /mpc8260 Files specific to Freescale MPC8260 CPUs 202 /mpc85xx Files specific to Freescale MPC85xx CPUs 203 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 204 /lib Architecture specific library files 205 /sh Files generic to SH architecture 206 /cpu CPU specific files 207 /sh2 Files specific to sh2 CPUs 208 /sh3 Files specific to sh3 CPUs 209 /sh4 Files specific to sh4 CPUs 210 /lib Architecture specific library files 211 /sparc Files generic to SPARC architecture 212 /cpu CPU specific files 213 /leon2 Files specific to Gaisler LEON2 SPARC CPU 214 /leon3 Files specific to Gaisler LEON3 SPARC CPU 215 /lib Architecture specific library files 216/api Machine/arch independent API for external apps 217/board Board dependent files 218/common Misc architecture independent functions 219/disk Code for disk drive partition handling 220/doc Documentation (don't expect too much) 221/drivers Commonly used device drivers 222/examples Example code for standalone applications, etc. 223/fs Filesystem code (cramfs, ext2, jffs2, etc.) 224/include Header Files 225/lib Files generic to all architectures 226 /libfdt Library files to support flattened device trees 227 /lzma Library files to support LZMA decompression 228 /lzo Library files to support LZO decompression 229/net Networking code 230/post Power On Self Test 231/rtc Real Time Clock drivers 232/tools Tools to build S-Record or U-Boot images, etc. 233 234Software Configuration: 235======================= 236 237Configuration is usually done using C preprocessor defines; the 238rationale behind that is to avoid dead code whenever possible. 239 240There are two classes of configuration variables: 241 242* Configuration _OPTIONS_: 243 These are selectable by the user and have names beginning with 244 "CONFIG_". 245 246* Configuration _SETTINGS_: 247 These depend on the hardware etc. and should not be meddled with if 248 you don't know what you're doing; they have names beginning with 249 "CONFIG_SYS_". 250 251Later we will add a configuration tool - probably similar to or even 252identical to what's used for the Linux kernel. Right now, we have to 253do the configuration by hand, which means creating some symbolic 254links and editing some configuration files. We use the TQM8xxL boards 255as an example here. 256 257 258Selection of Processor Architecture and Board Type: 259--------------------------------------------------- 260 261For all supported boards there are ready-to-use default 262configurations available; just type "make <board_name>_config". 263 264Example: For a TQM823L module type: 265 266 cd u-boot 267 make TQM823L_config 268 269For the Cogent platform, you need to specify the CPU type as well; 270e.g. "make cogent_mpc8xx_config". And also configure the cogent 271directory according to the instructions in cogent/README. 272 273 274Configuration Options: 275---------------------- 276 277Configuration depends on the combination of board and CPU type; all 278such information is kept in a configuration file 279"include/configs/<board_name>.h". 280 281Example: For a TQM823L module, all configuration settings are in 282"include/configs/TQM823L.h". 283 284 285Many of the options are named exactly as the corresponding Linux 286kernel configuration options. The intention is to make it easier to 287build a config tool - later. 288 289 290The following options need to be configured: 291 292- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 293 294- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 295 296- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 297 Define exactly one, e.g. CONFIG_ATSTK1002 298 299- CPU Module Type: (if CONFIG_COGENT is defined) 300 Define exactly one of 301 CONFIG_CMA286_60_OLD 302--- FIXME --- not tested yet: 303 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 304 CONFIG_CMA287_23, CONFIG_CMA287_50 305 306- Motherboard Type: (if CONFIG_COGENT is defined) 307 Define exactly one of 308 CONFIG_CMA101, CONFIG_CMA102 309 310- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 311 Define one or more of 312 CONFIG_CMA302 313 314- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 315 Define one or more of 316 CONFIG_LCD_HEARTBEAT - update a character position on 317 the LCD display every second with 318 a "rotator" |\-/|\-/ 319 320- Board flavour: (if CONFIG_MPC8260ADS is defined) 321 CONFIG_ADSTYPE 322 Possible values are: 323 CONFIG_SYS_8260ADS - original MPC8260ADS 324 CONFIG_SYS_8266ADS - MPC8266ADS 325 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 326 CONFIG_SYS_8272ADS - MPC8272ADS 327 328- Marvell Family Member 329 CONFIG_SYS_MVFS - define it if you want to enable 330 multiple fs option at one time 331 for marvell soc family 332 333- MPC824X Family Member (if CONFIG_MPC824X is defined) 334 Define exactly one of 335 CONFIG_MPC8240, CONFIG_MPC8245 336 337- 8xx CPU Options: (if using an MPC8xx CPU) 338 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 339 get_gclk_freq() cannot work 340 e.g. if there is no 32KHz 341 reference PIT/RTC clock 342 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 343 or XTAL/EXTAL) 344 345- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 346 CONFIG_SYS_8xx_CPUCLK_MIN 347 CONFIG_SYS_8xx_CPUCLK_MAX 348 CONFIG_8xx_CPUCLK_DEFAULT 349 See doc/README.MPC866 350 351 CONFIG_SYS_MEASURE_CPUCLK 352 353 Define this to measure the actual CPU clock instead 354 of relying on the correctness of the configured 355 values. Mostly useful for board bringup to make sure 356 the PLL is locked at the intended frequency. Note 357 that this requires a (stable) reference clock (32 kHz 358 RTC clock or CONFIG_SYS_8XX_XIN) 359 360 CONFIG_SYS_DELAYED_ICACHE 361 362 Define this option if you want to enable the 363 ICache only when Code runs from RAM. 364 365- 85xx CPU Options: 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 Defines the core time base clock divider ratio compared to the 369 system clock. On most PQ3 devices this is 8, on newer QorIQ 370 devices it can be 16 or 32. The ratio varies from SoC to Soc. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377 CONFIG_SYS_PPC_E500_DEBUG_TLB 378 379 Enables a temporary TLB entry to be used during boot to work 380 around limitations in e500v1 and e500v2 external debugger 381 support. This reduces the portions of the boot code where 382 breakpoints and single stepping do not work. The value of this 383 symbol should be set to the TLB1 entry to be used for this 384 purpose. 385 386 CONFIG_SYS_FSL_ERRATUM_A004510 387 388 Enables a workaround for erratum A004510. If set, 389 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 390 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 391 392 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 393 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 394 395 Defines one or two SoC revisions (low 8 bits of SVR) 396 for which the A004510 workaround should be applied. 397 398 The rest of SVR is either not relevant to the decision 399 of whether the erratum is present (e.g. p2040 versus 400 p2041) or is implied by the build target, which controls 401 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 402 403 See Freescale App Note 4493 for more information about 404 this erratum. 405 406 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 407 408 This is the value to write into CCSR offset 0x18600 409 according to the A004510 workaround. 410 411- Generic CPU options: 412 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 413 414 Defines the endianess of the CPU. Implementation of those 415 values is arch specific. 416 417- Intel Monahans options: 418 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 419 420 Defines the Monahans run mode to oscillator 421 ratio. Valid values are 8, 16, 24, 31. The core 422 frequency is this value multiplied by 13 MHz. 423 424 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 425 426 Defines the Monahans turbo mode to oscillator 427 ratio. Valid values are 1 (default if undefined) and 428 2. The core frequency as calculated above is multiplied 429 by this value. 430 431- MIPS CPU options: 432 CONFIG_SYS_INIT_SP_OFFSET 433 434 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 435 pointer. This is needed for the temporary stack before 436 relocation. 437 438 CONFIG_SYS_MIPS_CACHE_MODE 439 440 Cache operation mode for the MIPS CPU. 441 See also arch/mips/include/asm/mipsregs.h. 442 Possible values are: 443 CONF_CM_CACHABLE_NO_WA 444 CONF_CM_CACHABLE_WA 445 CONF_CM_UNCACHED 446 CONF_CM_CACHABLE_NONCOHERENT 447 CONF_CM_CACHABLE_CE 448 CONF_CM_CACHABLE_COW 449 CONF_CM_CACHABLE_CUW 450 CONF_CM_CACHABLE_ACCELERATED 451 452 CONFIG_SYS_XWAY_EBU_BOOTCFG 453 454 Special option for Lantiq XWAY SoCs for booting from NOR flash. 455 See also arch/mips/cpu/mips32/start.S. 456 457 CONFIG_XWAY_SWAP_BYTES 458 459 Enable compilation of tools/xway-swap-bytes needed for Lantiq 460 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 461 be swapped if a flash programmer is used. 462 463- ARM options: 464 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 465 466 Select high exception vectors of the ARM core, e.g., do not 467 clear the V bit of the c1 register of CP15. 468 469 CONFIG_SYS_THUMB_BUILD 470 471 Use this flag to build U-Boot using the Thumb instruction 472 set for ARM architectures. Thumb instruction set provides 473 better code density. For ARM architectures that support 474 Thumb2 this flag will result in Thumb2 code generated by 475 GCC. 476 477- Linux Kernel Interface: 478 CONFIG_CLOCKS_IN_MHZ 479 480 U-Boot stores all clock information in Hz 481 internally. For binary compatibility with older Linux 482 kernels (which expect the clocks passed in the 483 bd_info data to be in MHz) the environment variable 484 "clocks_in_mhz" can be defined so that U-Boot 485 converts clock data to MHZ before passing it to the 486 Linux kernel. 487 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 488 "clocks_in_mhz=1" is automatically included in the 489 default environment. 490 491 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 492 493 When transferring memsize parameter to linux, some versions 494 expect it to be in bytes, others in MB. 495 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 496 497 CONFIG_OF_LIBFDT 498 499 New kernel versions are expecting firmware settings to be 500 passed using flattened device trees (based on open firmware 501 concepts). 502 503 CONFIG_OF_LIBFDT 504 * New libfdt-based support 505 * Adds the "fdt" command 506 * The bootm command automatically updates the fdt 507 508 OF_CPU - The proper name of the cpus node (only required for 509 MPC512X and MPC5xxx based boards). 510 OF_SOC - The proper name of the soc node (only required for 511 MPC512X and MPC5xxx based boards). 512 OF_TBCLK - The timebase frequency. 513 OF_STDOUT_PATH - The path to the console device 514 515 boards with QUICC Engines require OF_QE to set UCC MAC 516 addresses 517 518 CONFIG_OF_BOARD_SETUP 519 520 Board code has addition modification that it wants to make 521 to the flat device tree before handing it off to the kernel 522 523 CONFIG_OF_BOOT_CPU 524 525 This define fills in the correct boot CPU in the boot 526 param header, the default value is zero if undefined. 527 528 CONFIG_OF_IDE_FIXUP 529 530 U-Boot can detect if an IDE device is present or not. 531 If not, and this new config option is activated, U-Boot 532 removes the ATA node from the DTS before booting Linux, 533 so the Linux IDE driver does not probe the device and 534 crash. This is needed for buggy hardware (uc101) where 535 no pull down resistor is connected to the signal IDE5V_DD7. 536 537 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 538 539 This setting is mandatory for all boards that have only one 540 machine type and must be used to specify the machine type 541 number as it appears in the ARM machine registry 542 (see http://www.arm.linux.org.uk/developer/machines/). 543 Only boards that have multiple machine types supported 544 in a single configuration file and the machine type is 545 runtime discoverable, do not have to use this setting. 546 547- vxWorks boot parameters: 548 549 bootvx constructs a valid bootline using the following 550 environments variables: bootfile, ipaddr, serverip, hostname. 551 It loads the vxWorks image pointed bootfile. 552 553 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 554 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 555 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 556 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 557 558 CONFIG_SYS_VXWORKS_ADD_PARAMS 559 560 Add it at the end of the bootline. E.g "u=username pw=secret" 561 562 Note: If a "bootargs" environment is defined, it will overwride 563 the defaults discussed just above. 564 565- Cache Configuration: 566 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 567 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 568 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 569 570- Cache Configuration for ARM: 571 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 572 controller 573 CONFIG_SYS_PL310_BASE - Physical base address of PL310 574 controller register space 575 576- Serial Ports: 577 CONFIG_PL010_SERIAL 578 579 Define this if you want support for Amba PrimeCell PL010 UARTs. 580 581 CONFIG_PL011_SERIAL 582 583 Define this if you want support for Amba PrimeCell PL011 UARTs. 584 585 CONFIG_PL011_CLOCK 586 587 If you have Amba PrimeCell PL011 UARTs, set this variable to 588 the clock speed of the UARTs. 589 590 CONFIG_PL01x_PORTS 591 592 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 593 define this to a list of base addresses for each (supported) 594 port. See e.g. include/configs/versatile.h 595 596 CONFIG_PL011_SERIAL_RLCR 597 598 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 599 have separate receive and transmit line control registers. Set 600 this variable to initialize the extra register. 601 602 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 603 604 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 605 boot loader that has already initialized the UART. Define this 606 variable to flush the UART at init time. 607 608 609- Console Interface: 610 Depending on board, define exactly one serial port 611 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 612 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 613 console by defining CONFIG_8xx_CONS_NONE 614 615 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 616 port routines must be defined elsewhere 617 (i.e. serial_init(), serial_getc(), ...) 618 619 CONFIG_CFB_CONSOLE 620 Enables console device for a color framebuffer. Needs following 621 defines (cf. smiLynxEM, i8042) 622 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 623 (default big endian) 624 VIDEO_HW_RECTFILL graphic chip supports 625 rectangle fill 626 (cf. smiLynxEM) 627 VIDEO_HW_BITBLT graphic chip supports 628 bit-blit (cf. smiLynxEM) 629 VIDEO_VISIBLE_COLS visible pixel columns 630 (cols=pitch) 631 VIDEO_VISIBLE_ROWS visible pixel rows 632 VIDEO_PIXEL_SIZE bytes per pixel 633 VIDEO_DATA_FORMAT graphic data format 634 (0-5, cf. cfb_console.c) 635 VIDEO_FB_ADRS framebuffer address 636 VIDEO_KBD_INIT_FCT keyboard int fct 637 (i.e. i8042_kbd_init()) 638 VIDEO_TSTC_FCT test char fct 639 (i.e. i8042_tstc) 640 VIDEO_GETC_FCT get char fct 641 (i.e. i8042_getc) 642 CONFIG_CONSOLE_CURSOR cursor drawing on/off 643 (requires blink timer 644 cf. i8042.c) 645 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 646 CONFIG_CONSOLE_TIME display time/date info in 647 upper right corner 648 (requires CONFIG_CMD_DATE) 649 CONFIG_VIDEO_LOGO display Linux logo in 650 upper left corner 651 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 652 linux_logo.h for logo. 653 Requires CONFIG_VIDEO_LOGO 654 CONFIG_CONSOLE_EXTRA_INFO 655 additional board info beside 656 the logo 657 658 When CONFIG_CFB_CONSOLE is defined, video console is 659 default i/o. Serial console can be forced with 660 environment 'console=serial'. 661 662 When CONFIG_SILENT_CONSOLE is defined, all console 663 messages (by U-Boot and Linux!) can be silenced with 664 the "silent" environment variable. See 665 doc/README.silent for more information. 666 667- Console Baudrate: 668 CONFIG_BAUDRATE - in bps 669 Select one of the baudrates listed in 670 CONFIG_SYS_BAUDRATE_TABLE, see below. 671 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 672 673- Console Rx buffer length 674 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 675 the maximum receive buffer length for the SMC. 676 This option is actual only for 82xx and 8xx possible. 677 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 678 must be defined, to setup the maximum idle timeout for 679 the SMC. 680 681- Pre-Console Buffer: 682 Prior to the console being initialised (i.e. serial UART 683 initialised etc) all console output is silently discarded. 684 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 685 buffer any console messages prior to the console being 686 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 687 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 688 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 689 bytes are output before the console is initialised, the 690 earlier bytes are discarded. 691 692 'Sane' compilers will generate smaller code if 693 CONFIG_PRE_CON_BUF_SZ is a power of 2 694 695- Safe printf() functions 696 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 697 the printf() functions. These are defined in 698 include/vsprintf.h and include snprintf(), vsnprintf() and 699 so on. Code size increase is approximately 300-500 bytes. 700 If this option is not given then these functions will 701 silently discard their buffer size argument - this means 702 you are not getting any overflow checking in this case. 703 704- Boot Delay: CONFIG_BOOTDELAY - in seconds 705 Delay before automatically booting the default image; 706 set to -1 to disable autoboot. 707 set to -2 to autoboot with no delay and not check for abort 708 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 709 710 See doc/README.autoboot for these options that 711 work with CONFIG_BOOTDELAY. None are required. 712 CONFIG_BOOT_RETRY_TIME 713 CONFIG_BOOT_RETRY_MIN 714 CONFIG_AUTOBOOT_KEYED 715 CONFIG_AUTOBOOT_PROMPT 716 CONFIG_AUTOBOOT_DELAY_STR 717 CONFIG_AUTOBOOT_STOP_STR 718 CONFIG_AUTOBOOT_DELAY_STR2 719 CONFIG_AUTOBOOT_STOP_STR2 720 CONFIG_ZERO_BOOTDELAY_CHECK 721 CONFIG_RESET_TO_RETRY 722 723- Autoboot Command: 724 CONFIG_BOOTCOMMAND 725 Only needed when CONFIG_BOOTDELAY is enabled; 726 define a command string that is automatically executed 727 when no character is read on the console interface 728 within "Boot Delay" after reset. 729 730 CONFIG_BOOTARGS 731 This can be used to pass arguments to the bootm 732 command. The value of CONFIG_BOOTARGS goes into the 733 environment value "bootargs". 734 735 CONFIG_RAMBOOT and CONFIG_NFSBOOT 736 The value of these goes into the environment as 737 "ramboot" and "nfsboot" respectively, and can be used 738 as a convenience, when switching between booting from 739 RAM and NFS. 740 741- Pre-Boot Commands: 742 CONFIG_PREBOOT 743 744 When this option is #defined, the existence of the 745 environment variable "preboot" will be checked 746 immediately before starting the CONFIG_BOOTDELAY 747 countdown and/or running the auto-boot command resp. 748 entering interactive mode. 749 750 This feature is especially useful when "preboot" is 751 automatically generated or modified. For an example 752 see the LWMON board specific code: here "preboot" is 753 modified when the user holds down a certain 754 combination of keys on the (special) keyboard when 755 booting the systems 756 757- Serial Download Echo Mode: 758 CONFIG_LOADS_ECHO 759 If defined to 1, all characters received during a 760 serial download (using the "loads" command) are 761 echoed back. This might be needed by some terminal 762 emulations (like "cu"), but may as well just take 763 time on others. This setting #define's the initial 764 value of the "loads_echo" environment variable. 765 766- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 767 CONFIG_KGDB_BAUDRATE 768 Select one of the baudrates listed in 769 CONFIG_SYS_BAUDRATE_TABLE, see below. 770 771- Monitor Functions: 772 Monitor commands can be included or excluded 773 from the build by using the #include files 774 <config_cmd_all.h> and #undef'ing unwanted 775 commands, or using <config_cmd_default.h> 776 and augmenting with additional #define's 777 for wanted commands. 778 779 The default command configuration includes all commands 780 except those marked below with a "*". 781 782 CONFIG_CMD_ASKENV * ask for env variable 783 CONFIG_CMD_BDI bdinfo 784 CONFIG_CMD_BEDBUG * Include BedBug Debugger 785 CONFIG_CMD_BMP * BMP support 786 CONFIG_CMD_BSP * Board specific commands 787 CONFIG_CMD_BOOTD bootd 788 CONFIG_CMD_CACHE * icache, dcache 789 CONFIG_CMD_CONSOLE coninfo 790 CONFIG_CMD_CRC32 * crc32 791 CONFIG_CMD_DATE * support for RTC, date/time... 792 CONFIG_CMD_DHCP * DHCP support 793 CONFIG_CMD_DIAG * Diagnostics 794 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 795 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 796 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 797 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 798 CONFIG_CMD_DTT * Digital Therm and Thermostat 799 CONFIG_CMD_ECHO echo arguments 800 CONFIG_CMD_EDITENV edit env variable 801 CONFIG_CMD_EEPROM * EEPROM read/write support 802 CONFIG_CMD_ELF * bootelf, bootvx 803 CONFIG_CMD_EXPORTENV * export the environment 804 CONFIG_CMD_SAVEENV saveenv 805 CONFIG_CMD_FDC * Floppy Disk Support 806 CONFIG_CMD_FAT * FAT partition support 807 CONFIG_CMD_FDOS * Dos diskette Support 808 CONFIG_CMD_FLASH flinfo, erase, protect 809 CONFIG_CMD_FPGA FPGA device initialization support 810 CONFIG_CMD_GO * the 'go' command (exec code) 811 CONFIG_CMD_GREPENV * search environment 812 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 813 CONFIG_CMD_I2C * I2C serial bus support 814 CONFIG_CMD_IDE * IDE harddisk support 815 CONFIG_CMD_IMI iminfo 816 CONFIG_CMD_IMLS List all found images 817 CONFIG_CMD_IMMAP * IMMR dump support 818 CONFIG_CMD_IMPORTENV * import an environment 819 CONFIG_CMD_IRQ * irqinfo 820 CONFIG_CMD_ITEST Integer/string test of 2 values 821 CONFIG_CMD_JFFS2 * JFFS2 Support 822 CONFIG_CMD_KGDB * kgdb 823 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader) 824 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 825 (169.254.*.*) 826 CONFIG_CMD_LOADB loadb 827 CONFIG_CMD_LOADS loads 828 CONFIG_CMD_MD5SUM print md5 message digest 829 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 830 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 831 loop, loopw, mtest 832 CONFIG_CMD_MISC Misc functions like sleep etc 833 CONFIG_CMD_MMC * MMC memory mapped support 834 CONFIG_CMD_MII * MII utility commands 835 CONFIG_CMD_MTDPARTS * MTD partition support 836 CONFIG_CMD_NAND * NAND support 837 CONFIG_CMD_NET bootp, tftpboot, rarpboot 838 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 839 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 840 CONFIG_CMD_PCI * pciinfo 841 CONFIG_CMD_PCMCIA * PCMCIA support 842 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 843 host 844 CONFIG_CMD_PORTIO * Port I/O 845 CONFIG_CMD_REGINFO * Register dump 846 CONFIG_CMD_RUN run command in env variable 847 CONFIG_CMD_SAVES * save S record dump 848 CONFIG_CMD_SCSI * SCSI Support 849 CONFIG_CMD_SDRAM * print SDRAM configuration information 850 (requires CONFIG_CMD_I2C) 851 CONFIG_CMD_SETGETDCR Support for DCR Register access 852 (4xx only) 853 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 854 CONFIG_CMD_SHA1SUM print sha1 memory digest 855 (requires CONFIG_CMD_MEMORY) 856 CONFIG_CMD_SOURCE "source" command Support 857 CONFIG_CMD_SPI * SPI serial bus support 858 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 859 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 860 CONFIG_CMD_TIME * run command and report execution time 861 CONFIG_CMD_USB * USB support 862 CONFIG_CMD_CDP * Cisco Discover Protocol support 863 CONFIG_CMD_MFSL * Microblaze FSL support 864 865 866 EXAMPLE: If you want all functions except of network 867 support you can write: 868 869 #include "config_cmd_all.h" 870 #undef CONFIG_CMD_NET 871 872 Other Commands: 873 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 874 875 Note: Don't enable the "icache" and "dcache" commands 876 (configuration option CONFIG_CMD_CACHE) unless you know 877 what you (and your U-Boot users) are doing. Data 878 cache cannot be enabled on systems like the 8xx or 879 8260 (where accesses to the IMMR region must be 880 uncached), and it cannot be disabled on all other 881 systems where we (mis-) use the data cache to hold an 882 initial stack and some data. 883 884 885 XXX - this list needs to get updated! 886 887- Device tree: 888 CONFIG_OF_CONTROL 889 If this variable is defined, U-Boot will use a device tree 890 to configure its devices, instead of relying on statically 891 compiled #defines in the board file. This option is 892 experimental and only available on a few boards. The device 893 tree is available in the global data as gd->fdt_blob. 894 895 U-Boot needs to get its device tree from somewhere. This can 896 be done using one of the two options below: 897 898 CONFIG_OF_EMBED 899 If this variable is defined, U-Boot will embed a device tree 900 binary in its image. This device tree file should be in the 901 board directory and called <soc>-<board>.dts. The binary file 902 is then picked up in board_init_f() and made available through 903 the global data structure as gd->blob. 904 905 CONFIG_OF_SEPARATE 906 If this variable is defined, U-Boot will build a device tree 907 binary. It will be called u-boot.dtb. Architecture-specific 908 code will locate it at run-time. Generally this works by: 909 910 cat u-boot.bin u-boot.dtb >image.bin 911 912 and in fact, U-Boot does this for you, creating a file called 913 u-boot-dtb.bin which is useful in the common case. You can 914 still use the individual files if you need something more 915 exotic. 916 917- Watchdog: 918 CONFIG_WATCHDOG 919 If this variable is defined, it enables watchdog 920 support for the SoC. There must be support in the SoC 921 specific code for a watchdog. For the 8xx and 8260 922 CPUs, the SIU Watchdog feature is enabled in the SYPCR 923 register. When supported for a specific SoC is 924 available, then no further board specific code should 925 be needed to use it. 926 927 CONFIG_HW_WATCHDOG 928 When using a watchdog circuitry external to the used 929 SoC, then define this variable and provide board 930 specific code for the "hw_watchdog_reset" function. 931 932- U-Boot Version: 933 CONFIG_VERSION_VARIABLE 934 If this variable is defined, an environment variable 935 named "ver" is created by U-Boot showing the U-Boot 936 version as printed by the "version" command. 937 Any change to this variable will be reverted at the 938 next reset. 939 940- Real-Time Clock: 941 942 When CONFIG_CMD_DATE is selected, the type of the RTC 943 has to be selected, too. Define exactly one of the 944 following options: 945 946 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 947 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 948 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 949 CONFIG_RTC_MC146818 - use MC146818 RTC 950 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 951 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 952 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 953 CONFIG_RTC_DS164x - use Dallas DS164x RTC 954 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 955 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 956 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 957 CONFIG_SYS_RV3029_TCR - enable trickle charger on 958 RV3029 RTC. 959 960 Note that if the RTC uses I2C, then the I2C interface 961 must also be configured. See I2C Support, below. 962 963- GPIO Support: 964 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 965 CONFIG_PCA953X_INFO - enable pca953x info command 966 967 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 968 chip-ngpio pairs that tell the PCA953X driver the number of 969 pins supported by a particular chip. 970 971 Note that if the GPIO device uses I2C, then the I2C interface 972 must also be configured. See I2C Support, below. 973 974- Timestamp Support: 975 976 When CONFIG_TIMESTAMP is selected, the timestamp 977 (date and time) of an image is printed by image 978 commands like bootm or iminfo. This option is 979 automatically enabled when you select CONFIG_CMD_DATE . 980 981- Partition Labels (disklabels) Supported: 982 Zero or more of the following: 983 CONFIG_MAC_PARTITION Apple's MacOS partition table. 984 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 985 Intel architecture, USB sticks, etc. 986 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 987 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 988 bootloader. Note 2TB partition limit; see 989 disk/part_efi.c 990 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 991 992 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 993 CONFIG_CMD_SCSI) you must configure support for at 994 least one non-MTD partition type as well. 995 996- IDE Reset method: 997 CONFIG_IDE_RESET_ROUTINE - this is defined in several 998 board configurations files but used nowhere! 999 1000 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1001 be performed by calling the function 1002 ide_set_reset(int reset) 1003 which has to be defined in a board specific file 1004 1005- ATAPI Support: 1006 CONFIG_ATAPI 1007 1008 Set this to enable ATAPI support. 1009 1010- LBA48 Support 1011 CONFIG_LBA48 1012 1013 Set this to enable support for disks larger than 137GB 1014 Also look at CONFIG_SYS_64BIT_LBA. 1015 Whithout these , LBA48 support uses 32bit variables and will 'only' 1016 support disks up to 2.1TB. 1017 1018 CONFIG_SYS_64BIT_LBA: 1019 When enabled, makes the IDE subsystem use 64bit sector addresses. 1020 Default is 32bit. 1021 1022- SCSI Support: 1023 At the moment only there is only support for the 1024 SYM53C8XX SCSI controller; define 1025 CONFIG_SCSI_SYM53C8XX to enable it. 1026 1027 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1028 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1029 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1030 maximum numbers of LUNs, SCSI ID's and target 1031 devices. 1032 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1033 1034- NETWORK Support (PCI): 1035 CONFIG_E1000 1036 Support for Intel 8254x/8257x gigabit chips. 1037 1038 CONFIG_E1000_SPI 1039 Utility code for direct access to the SPI bus on Intel 8257x. 1040 This does not do anything useful unless you set at least one 1041 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1042 1043 CONFIG_E1000_SPI_GENERIC 1044 Allow generic access to the SPI bus on the Intel 8257x, for 1045 example with the "sspi" command. 1046 1047 CONFIG_CMD_E1000 1048 Management command for E1000 devices. When used on devices 1049 with SPI support you can reprogram the EEPROM from U-Boot. 1050 1051 CONFIG_E1000_FALLBACK_MAC 1052 default MAC for empty EEPROM after production. 1053 1054 CONFIG_EEPRO100 1055 Support for Intel 82557/82559/82559ER chips. 1056 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1057 write routine for first time initialisation. 1058 1059 CONFIG_TULIP 1060 Support for Digital 2114x chips. 1061 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1062 modem chip initialisation (KS8761/QS6611). 1063 1064 CONFIG_NATSEMI 1065 Support for National dp83815 chips. 1066 1067 CONFIG_NS8382X 1068 Support for National dp8382[01] gigabit chips. 1069 1070- NETWORK Support (other): 1071 1072 CONFIG_DRIVER_AT91EMAC 1073 Support for AT91RM9200 EMAC. 1074 1075 CONFIG_RMII 1076 Define this to use reduced MII inteface 1077 1078 CONFIG_DRIVER_AT91EMAC_QUIET 1079 If this defined, the driver is quiet. 1080 The driver doen't show link status messages. 1081 1082 CONFIG_CALXEDA_XGMAC 1083 Support for the Calxeda XGMAC device 1084 1085 CONFIG_DRIVER_LAN91C96 1086 Support for SMSC's LAN91C96 chips. 1087 1088 CONFIG_LAN91C96_BASE 1089 Define this to hold the physical address 1090 of the LAN91C96's I/O space 1091 1092 CONFIG_LAN91C96_USE_32_BIT 1093 Define this to enable 32 bit addressing 1094 1095 CONFIG_DRIVER_SMC91111 1096 Support for SMSC's LAN91C111 chip 1097 1098 CONFIG_SMC91111_BASE 1099 Define this to hold the physical address 1100 of the device (I/O space) 1101 1102 CONFIG_SMC_USE_32_BIT 1103 Define this if data bus is 32 bits 1104 1105 CONFIG_SMC_USE_IOFUNCS 1106 Define this to use i/o functions instead of macros 1107 (some hardware wont work with macros) 1108 1109 CONFIG_DRIVER_TI_EMAC 1110 Support for davinci emac 1111 1112 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1113 Define this if you have more then 3 PHYs. 1114 1115 CONFIG_FTGMAC100 1116 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1117 1118 CONFIG_FTGMAC100_EGIGA 1119 Define this to use GE link update with gigabit PHY. 1120 Define this if FTGMAC100 is connected to gigabit PHY. 1121 If your system has 10/100 PHY only, it might not occur 1122 wrong behavior. Because PHY usually return timeout or 1123 useless data when polling gigabit status and gigabit 1124 control registers. This behavior won't affect the 1125 correctnessof 10/100 link speed update. 1126 1127 CONFIG_SMC911X 1128 Support for SMSC's LAN911x and LAN921x chips 1129 1130 CONFIG_SMC911X_BASE 1131 Define this to hold the physical address 1132 of the device (I/O space) 1133 1134 CONFIG_SMC911X_32_BIT 1135 Define this if data bus is 32 bits 1136 1137 CONFIG_SMC911X_16_BIT 1138 Define this if data bus is 16 bits. If your processor 1139 automatically converts one 32 bit word to two 16 bit 1140 words you may also try CONFIG_SMC911X_32_BIT. 1141 1142 CONFIG_SH_ETHER 1143 Support for Renesas on-chip Ethernet controller 1144 1145 CONFIG_SH_ETHER_USE_PORT 1146 Define the number of ports to be used 1147 1148 CONFIG_SH_ETHER_PHY_ADDR 1149 Define the ETH PHY's address 1150 1151 CONFIG_SH_ETHER_CACHE_WRITEBACK 1152 If this option is set, the driver enables cache flush. 1153 1154- TPM Support: 1155 CONFIG_GENERIC_LPC_TPM 1156 Support for generic parallel port TPM devices. Only one device 1157 per system is supported at this time. 1158 1159 CONFIG_TPM_TIS_BASE_ADDRESS 1160 Base address where the generic TPM device is mapped 1161 to. Contemporary x86 systems usually map it at 1162 0xfed40000. 1163 1164- USB Support: 1165 At the moment only the UHCI host controller is 1166 supported (PIP405, MIP405, MPC5200); define 1167 CONFIG_USB_UHCI to enable it. 1168 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1169 and define CONFIG_USB_STORAGE to enable the USB 1170 storage devices. 1171 Note: 1172 Supported are USB Keyboards and USB Floppy drives 1173 (TEAC FD-05PUB). 1174 MPC5200 USB requires additional defines: 1175 CONFIG_USB_CLOCK 1176 for 528 MHz Clock: 0x0001bbbb 1177 CONFIG_PSC3_USB 1178 for USB on PSC3 1179 CONFIG_USB_CONFIG 1180 for differential drivers: 0x00001000 1181 for single ended drivers: 0x00005000 1182 for differential drivers on PSC3: 0x00000100 1183 for single ended drivers on PSC3: 0x00004100 1184 CONFIG_SYS_USB_EVENT_POLL 1185 May be defined to allow interrupt polling 1186 instead of using asynchronous interrupts 1187 1188 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1189 txfilltuning field in the EHCI controller on reset. 1190 1191- USB Device: 1192 Define the below if you wish to use the USB console. 1193 Once firmware is rebuilt from a serial console issue the 1194 command "setenv stdin usbtty; setenv stdout usbtty" and 1195 attach your USB cable. The Unix command "dmesg" should print 1196 it has found a new device. The environment variable usbtty 1197 can be set to gserial or cdc_acm to enable your device to 1198 appear to a USB host as a Linux gserial device or a 1199 Common Device Class Abstract Control Model serial device. 1200 If you select usbtty = gserial you should be able to enumerate 1201 a Linux host by 1202 # modprobe usbserial vendor=0xVendorID product=0xProductID 1203 else if using cdc_acm, simply setting the environment 1204 variable usbtty to be cdc_acm should suffice. The following 1205 might be defined in YourBoardName.h 1206 1207 CONFIG_USB_DEVICE 1208 Define this to build a UDC device 1209 1210 CONFIG_USB_TTY 1211 Define this to have a tty type of device available to 1212 talk to the UDC device 1213 1214 CONFIG_USBD_HS 1215 Define this to enable the high speed support for usb 1216 device and usbtty. If this feature is enabled, a routine 1217 int is_usbd_high_speed(void) 1218 also needs to be defined by the driver to dynamically poll 1219 whether the enumeration has succeded at high speed or full 1220 speed. 1221 1222 CONFIG_SYS_CONSOLE_IS_IN_ENV 1223 Define this if you want stdin, stdout &/or stderr to 1224 be set to usbtty. 1225 1226 mpc8xx: 1227 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1228 Derive USB clock from external clock "blah" 1229 - CONFIG_SYS_USB_EXTC_CLK 0x02 1230 1231 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1232 Derive USB clock from brgclk 1233 - CONFIG_SYS_USB_BRG_CLK 0x04 1234 1235 If you have a USB-IF assigned VendorID then you may wish to 1236 define your own vendor specific values either in BoardName.h 1237 or directly in usbd_vendor_info.h. If you don't define 1238 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1239 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1240 should pretend to be a Linux device to it's target host. 1241 1242 CONFIG_USBD_MANUFACTURER 1243 Define this string as the name of your company for 1244 - CONFIG_USBD_MANUFACTURER "my company" 1245 1246 CONFIG_USBD_PRODUCT_NAME 1247 Define this string as the name of your product 1248 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1249 1250 CONFIG_USBD_VENDORID 1251 Define this as your assigned Vendor ID from the USB 1252 Implementors Forum. This *must* be a genuine Vendor ID 1253 to avoid polluting the USB namespace. 1254 - CONFIG_USBD_VENDORID 0xFFFF 1255 1256 CONFIG_USBD_PRODUCTID 1257 Define this as the unique Product ID 1258 for your device 1259 - CONFIG_USBD_PRODUCTID 0xFFFF 1260 1261- ULPI Layer Support: 1262 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1263 the generic ULPI layer. The generic layer accesses the ULPI PHY 1264 via the platform viewport, so you need both the genric layer and 1265 the viewport enabled. Currently only Chipidea/ARC based 1266 viewport is supported. 1267 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1268 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1269 1270- MMC Support: 1271 The MMC controller on the Intel PXA is supported. To 1272 enable this define CONFIG_MMC. The MMC can be 1273 accessed from the boot prompt by mapping the device 1274 to physical memory similar to flash. Command line is 1275 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1276 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1277 1278 CONFIG_SH_MMCIF 1279 Support for Renesas on-chip MMCIF controller 1280 1281 CONFIG_SH_MMCIF_ADDR 1282 Define the base address of MMCIF registers 1283 1284 CONFIG_SH_MMCIF_CLK 1285 Define the clock frequency for MMCIF 1286 1287- Journaling Flash filesystem support: 1288 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1289 CONFIG_JFFS2_NAND_DEV 1290 Define these for a default partition on a NAND device 1291 1292 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1293 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1294 Define these for a default partition on a NOR device 1295 1296 CONFIG_SYS_JFFS_CUSTOM_PART 1297 Define this to create an own partition. You have to provide a 1298 function struct part_info* jffs2_part_info(int part_num) 1299 1300 If you define only one JFFS2 partition you may also want to 1301 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1302 to disable the command chpart. This is the default when you 1303 have not defined a custom partition 1304 1305- FAT(File Allocation Table) filesystem write function support: 1306 CONFIG_FAT_WRITE 1307 1308 Define this to enable support for saving memory data as a 1309 file in FAT formatted partition. 1310 1311 This will also enable the command "fatwrite" enabling the 1312 user to write files to FAT. 1313 1314- Keyboard Support: 1315 CONFIG_ISA_KEYBOARD 1316 1317 Define this to enable standard (PC-Style) keyboard 1318 support 1319 1320 CONFIG_I8042_KBD 1321 Standard PC keyboard driver with US (is default) and 1322 GERMAN key layout (switch via environment 'keymap=de') support. 1323 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1324 for cfb_console. Supports cursor blinking. 1325 1326- Video support: 1327 CONFIG_VIDEO 1328 1329 Define this to enable video support (for output to 1330 video). 1331 1332 CONFIG_VIDEO_CT69000 1333 1334 Enable Chips & Technologies 69000 Video chip 1335 1336 CONFIG_VIDEO_SMI_LYNXEM 1337 Enable Silicon Motion SMI 712/710/810 Video chip. The 1338 video output is selected via environment 'videoout' 1339 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1340 assumed. 1341 1342 For the CT69000 and SMI_LYNXEM drivers, videomode is 1343 selected via environment 'videomode'. Two different ways 1344 are possible: 1345 - "videomode=num" 'num' is a standard LiLo mode numbers. 1346 Following standard modes are supported (* is default): 1347 1348 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1349 -------------+--------------------------------------------- 1350 8 bits | 0x301* 0x303 0x305 0x161 0x307 1351 15 bits | 0x310 0x313 0x316 0x162 0x319 1352 16 bits | 0x311 0x314 0x317 0x163 0x31A 1353 24 bits | 0x312 0x315 0x318 ? 0x31B 1354 -------------+--------------------------------------------- 1355 (i.e. setenv videomode 317; saveenv; reset;) 1356 1357 - "videomode=bootargs" all the video parameters are parsed 1358 from the bootargs. (See drivers/video/videomodes.c) 1359 1360 1361 CONFIG_VIDEO_SED13806 1362 Enable Epson SED13806 driver. This driver supports 8bpp 1363 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1364 or CONFIG_VIDEO_SED13806_16BPP 1365 1366 CONFIG_FSL_DIU_FB 1367 Enable the Freescale DIU video driver. Reference boards for 1368 SOCs that have a DIU should define this macro to enable DIU 1369 support, and should also define these other macros: 1370 1371 CONFIG_SYS_DIU_ADDR 1372 CONFIG_VIDEO 1373 CONFIG_CMD_BMP 1374 CONFIG_CFB_CONSOLE 1375 CONFIG_VIDEO_SW_CURSOR 1376 CONFIG_VGA_AS_SINGLE_DEVICE 1377 CONFIG_VIDEO_LOGO 1378 CONFIG_VIDEO_BMP_LOGO 1379 1380 The DIU driver will look for the 'video-mode' environment 1381 variable, and if defined, enable the DIU as a console during 1382 boot. See the documentation file README.video for a 1383 description of this variable. 1384 1385- Keyboard Support: 1386 CONFIG_KEYBOARD 1387 1388 Define this to enable a custom keyboard support. 1389 This simply calls drv_keyboard_init() which must be 1390 defined in your board-specific files. 1391 The only board using this so far is RBC823. 1392 1393- LCD Support: CONFIG_LCD 1394 1395 Define this to enable LCD support (for output to LCD 1396 display); also select one of the supported displays 1397 by defining one of these: 1398 1399 CONFIG_ATMEL_LCD: 1400 1401 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1402 1403 CONFIG_NEC_NL6448AC33: 1404 1405 NEC NL6448AC33-18. Active, color, single scan. 1406 1407 CONFIG_NEC_NL6448BC20 1408 1409 NEC NL6448BC20-08. 6.5", 640x480. 1410 Active, color, single scan. 1411 1412 CONFIG_NEC_NL6448BC33_54 1413 1414 NEC NL6448BC33-54. 10.4", 640x480. 1415 Active, color, single scan. 1416 1417 CONFIG_SHARP_16x9 1418 1419 Sharp 320x240. Active, color, single scan. 1420 It isn't 16x9, and I am not sure what it is. 1421 1422 CONFIG_SHARP_LQ64D341 1423 1424 Sharp LQ64D341 display, 640x480. 1425 Active, color, single scan. 1426 1427 CONFIG_HLD1045 1428 1429 HLD1045 display, 640x480. 1430 Active, color, single scan. 1431 1432 CONFIG_OPTREX_BW 1433 1434 Optrex CBL50840-2 NF-FW 99 22 M5 1435 or 1436 Hitachi LMG6912RPFC-00T 1437 or 1438 Hitachi SP14Q002 1439 1440 320x240. Black & white. 1441 1442 Normally display is black on white background; define 1443 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1444 1445- Splash Screen Support: CONFIG_SPLASH_SCREEN 1446 1447 If this option is set, the environment is checked for 1448 a variable "splashimage". If found, the usual display 1449 of logo, copyright and system information on the LCD 1450 is suppressed and the BMP image at the address 1451 specified in "splashimage" is loaded instead. The 1452 console is redirected to the "nulldev", too. This 1453 allows for a "silent" boot where a splash screen is 1454 loaded very quickly after power-on. 1455 1456 CONFIG_SPLASH_SCREEN_ALIGN 1457 1458 If this option is set the splash image can be freely positioned 1459 on the screen. Environment variable "splashpos" specifies the 1460 position as "x,y". If a positive number is given it is used as 1461 number of pixel from left/top. If a negative number is given it 1462 is used as number of pixel from right/bottom. You can also 1463 specify 'm' for centering the image. 1464 1465 Example: 1466 setenv splashpos m,m 1467 => image at center of screen 1468 1469 setenv splashpos 30,20 1470 => image at x = 30 and y = 20 1471 1472 setenv splashpos -10,m 1473 => vertically centered image 1474 at x = dspWidth - bmpWidth - 9 1475 1476- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1477 1478 If this option is set, additionally to standard BMP 1479 images, gzipped BMP images can be displayed via the 1480 splashscreen support or the bmp command. 1481 1482- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1483 1484 If this option is set, 8-bit RLE compressed BMP images 1485 can be displayed via the splashscreen support or the 1486 bmp command. 1487 1488- Do compresssing for memory range: 1489 CONFIG_CMD_ZIP 1490 1491 If this option is set, it would use zlib deflate method 1492 to compress the specified memory at its best effort. 1493 1494- Compression support: 1495 CONFIG_BZIP2 1496 1497 If this option is set, support for bzip2 compressed 1498 images is included. If not, only uncompressed and gzip 1499 compressed images are supported. 1500 1501 NOTE: the bzip2 algorithm requires a lot of RAM, so 1502 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1503 be at least 4MB. 1504 1505 CONFIG_LZMA 1506 1507 If this option is set, support for lzma compressed 1508 images is included. 1509 1510 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1511 requires an amount of dynamic memory that is given by the 1512 formula: 1513 1514 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1515 1516 Where lc and lp stand for, respectively, Literal context bits 1517 and Literal pos bits. 1518 1519 This value is upper-bounded by 14MB in the worst case. Anyway, 1520 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1521 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1522 a very small buffer. 1523 1524 Use the lzmainfo tool to determinate the lc and lp values and 1525 then calculate the amount of needed dynamic memory (ensuring 1526 the appropriate CONFIG_SYS_MALLOC_LEN value). 1527 1528- MII/PHY support: 1529 CONFIG_PHY_ADDR 1530 1531 The address of PHY on MII bus. 1532 1533 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1534 1535 The clock frequency of the MII bus 1536 1537 CONFIG_PHY_GIGE 1538 1539 If this option is set, support for speed/duplex 1540 detection of gigabit PHY is included. 1541 1542 CONFIG_PHY_RESET_DELAY 1543 1544 Some PHY like Intel LXT971A need extra delay after 1545 reset before any MII register access is possible. 1546 For such PHY, set this option to the usec delay 1547 required. (minimum 300usec for LXT971A) 1548 1549 CONFIG_PHY_CMD_DELAY (ppc4xx) 1550 1551 Some PHY like Intel LXT971A need extra delay after 1552 command issued before MII status register can be read 1553 1554- Ethernet address: 1555 CONFIG_ETHADDR 1556 CONFIG_ETH1ADDR 1557 CONFIG_ETH2ADDR 1558 CONFIG_ETH3ADDR 1559 CONFIG_ETH4ADDR 1560 CONFIG_ETH5ADDR 1561 1562 Define a default value for Ethernet address to use 1563 for the respective Ethernet interface, in case this 1564 is not determined automatically. 1565 1566- IP address: 1567 CONFIG_IPADDR 1568 1569 Define a default value for the IP address to use for 1570 the default Ethernet interface, in case this is not 1571 determined through e.g. bootp. 1572 (Environment variable "ipaddr") 1573 1574- Server IP address: 1575 CONFIG_SERVERIP 1576 1577 Defines a default value for the IP address of a TFTP 1578 server to contact when using the "tftboot" command. 1579 (Environment variable "serverip") 1580 1581 CONFIG_KEEP_SERVERADDR 1582 1583 Keeps the server's MAC address, in the env 'serveraddr' 1584 for passing to bootargs (like Linux's netconsole option) 1585 1586- Gateway IP address: 1587 CONFIG_GATEWAYIP 1588 1589 Defines a default value for the IP address of the 1590 default router where packets to other networks are 1591 sent to. 1592 (Environment variable "gatewayip") 1593 1594- Subnet mask: 1595 CONFIG_NETMASK 1596 1597 Defines a default value for the subnet mask (or 1598 routing prefix) which is used to determine if an IP 1599 address belongs to the local subnet or needs to be 1600 forwarded through a router. 1601 (Environment variable "netmask") 1602 1603- Multicast TFTP Mode: 1604 CONFIG_MCAST_TFTP 1605 1606 Defines whether you want to support multicast TFTP as per 1607 rfc-2090; for example to work with atftp. Lets lots of targets 1608 tftp down the same boot image concurrently. Note: the Ethernet 1609 driver in use must provide a function: mcast() to join/leave a 1610 multicast group. 1611 1612- BOOTP Recovery Mode: 1613 CONFIG_BOOTP_RANDOM_DELAY 1614 1615 If you have many targets in a network that try to 1616 boot using BOOTP, you may want to avoid that all 1617 systems send out BOOTP requests at precisely the same 1618 moment (which would happen for instance at recovery 1619 from a power failure, when all systems will try to 1620 boot, thus flooding the BOOTP server. Defining 1621 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1622 inserted before sending out BOOTP requests. The 1623 following delays are inserted then: 1624 1625 1st BOOTP request: delay 0 ... 1 sec 1626 2nd BOOTP request: delay 0 ... 2 sec 1627 3rd BOOTP request: delay 0 ... 4 sec 1628 4th and following 1629 BOOTP requests: delay 0 ... 8 sec 1630 1631- DHCP Advanced Options: 1632 You can fine tune the DHCP functionality by defining 1633 CONFIG_BOOTP_* symbols: 1634 1635 CONFIG_BOOTP_SUBNETMASK 1636 CONFIG_BOOTP_GATEWAY 1637 CONFIG_BOOTP_HOSTNAME 1638 CONFIG_BOOTP_NISDOMAIN 1639 CONFIG_BOOTP_BOOTPATH 1640 CONFIG_BOOTP_BOOTFILESIZE 1641 CONFIG_BOOTP_DNS 1642 CONFIG_BOOTP_DNS2 1643 CONFIG_BOOTP_SEND_HOSTNAME 1644 CONFIG_BOOTP_NTPSERVER 1645 CONFIG_BOOTP_TIMEOFFSET 1646 CONFIG_BOOTP_VENDOREX 1647 CONFIG_BOOTP_MAY_FAIL 1648 1649 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1650 environment variable, not the BOOTP server. 1651 1652 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1653 after the configured retry count, the call will fail 1654 instead of starting over. This can be used to fail over 1655 to Link-local IP address configuration if the DHCP server 1656 is not available. 1657 1658 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1659 serverip from a DHCP server, it is possible that more 1660 than one DNS serverip is offered to the client. 1661 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1662 serverip will be stored in the additional environment 1663 variable "dnsip2". The first DNS serverip is always 1664 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1665 is defined. 1666 1667 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1668 to do a dynamic update of a DNS server. To do this, they 1669 need the hostname of the DHCP requester. 1670 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1671 of the "hostname" environment variable is passed as 1672 option 12 to the DHCP server. 1673 1674 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1675 1676 A 32bit value in microseconds for a delay between 1677 receiving a "DHCP Offer" and sending the "DHCP Request". 1678 This fixes a problem with certain DHCP servers that don't 1679 respond 100% of the time to a "DHCP request". E.g. On an 1680 AT91RM9200 processor running at 180MHz, this delay needed 1681 to be *at least* 15,000 usec before a Windows Server 2003 1682 DHCP server would reply 100% of the time. I recommend at 1683 least 50,000 usec to be safe. The alternative is to hope 1684 that one of the retries will be successful but note that 1685 the DHCP timeout and retry process takes a longer than 1686 this delay. 1687 1688 - Link-local IP address negotiation: 1689 Negotiate with other link-local clients on the local network 1690 for an address that doesn't require explicit configuration. 1691 This is especially useful if a DHCP server cannot be guaranteed 1692 to exist in all environments that the device must operate. 1693 1694 See doc/README.link-local for more information. 1695 1696 - CDP Options: 1697 CONFIG_CDP_DEVICE_ID 1698 1699 The device id used in CDP trigger frames. 1700 1701 CONFIG_CDP_DEVICE_ID_PREFIX 1702 1703 A two character string which is prefixed to the MAC address 1704 of the device. 1705 1706 CONFIG_CDP_PORT_ID 1707 1708 A printf format string which contains the ascii name of 1709 the port. Normally is set to "eth%d" which sets 1710 eth0 for the first Ethernet, eth1 for the second etc. 1711 1712 CONFIG_CDP_CAPABILITIES 1713 1714 A 32bit integer which indicates the device capabilities; 1715 0x00000010 for a normal host which does not forwards. 1716 1717 CONFIG_CDP_VERSION 1718 1719 An ascii string containing the version of the software. 1720 1721 CONFIG_CDP_PLATFORM 1722 1723 An ascii string containing the name of the platform. 1724 1725 CONFIG_CDP_TRIGGER 1726 1727 A 32bit integer sent on the trigger. 1728 1729 CONFIG_CDP_POWER_CONSUMPTION 1730 1731 A 16bit integer containing the power consumption of the 1732 device in .1 of milliwatts. 1733 1734 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1735 1736 A byte containing the id of the VLAN. 1737 1738- Status LED: CONFIG_STATUS_LED 1739 1740 Several configurations allow to display the current 1741 status using a LED. For instance, the LED will blink 1742 fast while running U-Boot code, stop blinking as 1743 soon as a reply to a BOOTP request was received, and 1744 start blinking slow once the Linux kernel is running 1745 (supported by a status LED driver in the Linux 1746 kernel). Defining CONFIG_STATUS_LED enables this 1747 feature in U-Boot. 1748 1749- CAN Support: CONFIG_CAN_DRIVER 1750 1751 Defining CONFIG_CAN_DRIVER enables CAN driver support 1752 on those systems that support this (optional) 1753 feature, like the TQM8xxL modules. 1754 1755- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1756 1757 These enable I2C serial bus commands. Defining either of 1758 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1759 include the appropriate I2C driver for the selected CPU. 1760 1761 This will allow you to use i2c commands at the u-boot 1762 command line (as long as you set CONFIG_CMD_I2C in 1763 CONFIG_COMMANDS) and communicate with i2c based realtime 1764 clock chips. See common/cmd_i2c.c for a description of the 1765 command line interface. 1766 1767 CONFIG_HARD_I2C selects a hardware I2C controller. 1768 1769 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1770 bit-banging) driver instead of CPM or similar hardware 1771 support for I2C. 1772 1773 There are several other quantities that must also be 1774 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1775 1776 In both cases you will need to define CONFIG_SYS_I2C_SPEED 1777 to be the frequency (in Hz) at which you wish your i2c bus 1778 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 1779 the CPU's i2c node address). 1780 1781 Now, the u-boot i2c code for the mpc8xx 1782 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 1783 and so its address should therefore be cleared to 0 (See, 1784 eg, MPC823e User's Manual p.16-473). So, set 1785 CONFIG_SYS_I2C_SLAVE to 0. 1786 1787 CONFIG_SYS_I2C_INIT_MPC5XXX 1788 1789 When a board is reset during an i2c bus transfer 1790 chips might think that the current transfer is still 1791 in progress. Reset the slave devices by sending start 1792 commands until the slave device responds. 1793 1794 That's all that's required for CONFIG_HARD_I2C. 1795 1796 If you use the software i2c interface (CONFIG_SOFT_I2C) 1797 then the following macros need to be defined (examples are 1798 from include/configs/lwmon.h): 1799 1800 I2C_INIT 1801 1802 (Optional). Any commands necessary to enable the I2C 1803 controller or configure ports. 1804 1805 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1806 1807 I2C_PORT 1808 1809 (Only for MPC8260 CPU). The I/O port to use (the code 1810 assumes both bits are on the same port). Valid values 1811 are 0..3 for ports A..D. 1812 1813 I2C_ACTIVE 1814 1815 The code necessary to make the I2C data line active 1816 (driven). If the data line is open collector, this 1817 define can be null. 1818 1819 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1820 1821 I2C_TRISTATE 1822 1823 The code necessary to make the I2C data line tri-stated 1824 (inactive). If the data line is open collector, this 1825 define can be null. 1826 1827 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1828 1829 I2C_READ 1830 1831 Code that returns TRUE if the I2C data line is high, 1832 FALSE if it is low. 1833 1834 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1835 1836 I2C_SDA(bit) 1837 1838 If <bit> is TRUE, sets the I2C data line high. If it 1839 is FALSE, it clears it (low). 1840 1841 eg: #define I2C_SDA(bit) \ 1842 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1843 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1844 1845 I2C_SCL(bit) 1846 1847 If <bit> is TRUE, sets the I2C clock line high. If it 1848 is FALSE, it clears it (low). 1849 1850 eg: #define I2C_SCL(bit) \ 1851 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1852 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1853 1854 I2C_DELAY 1855 1856 This delay is invoked four times per clock cycle so this 1857 controls the rate of data transfer. The data rate thus 1858 is 1 / (I2C_DELAY * 4). Often defined to be something 1859 like: 1860 1861 #define I2C_DELAY udelay(2) 1862 1863 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1864 1865 If your arch supports the generic GPIO framework (asm/gpio.h), 1866 then you may alternatively define the two GPIOs that are to be 1867 used as SCL / SDA. Any of the previous I2C_xxx macros will 1868 have GPIO-based defaults assigned to them as appropriate. 1869 1870 You should define these to the GPIO value as given directly to 1871 the generic GPIO functions. 1872 1873 CONFIG_SYS_I2C_INIT_BOARD 1874 1875 When a board is reset during an i2c bus transfer 1876 chips might think that the current transfer is still 1877 in progress. On some boards it is possible to access 1878 the i2c SCLK line directly, either by using the 1879 processor pin as a GPIO or by having a second pin 1880 connected to the bus. If this option is defined a 1881 custom i2c_init_board() routine in boards/xxx/board.c 1882 is run early in the boot sequence. 1883 1884 CONFIG_SYS_I2C_BOARD_LATE_INIT 1885 1886 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 1887 defined a custom i2c_board_late_init() routine in 1888 boards/xxx/board.c is run AFTER the operations in i2c_init() 1889 is completed. This callpoint can be used to unreset i2c bus 1890 using CPU i2c controller register accesses for CPUs whose i2c 1891 controller provide such a method. It is called at the end of 1892 i2c_init() to allow i2c_init operations to setup the i2c bus 1893 controller on the CPU (e.g. setting bus speed & slave address). 1894 1895 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1896 1897 This option enables configuration of bi_iic_fast[] flags 1898 in u-boot bd_info structure based on u-boot environment 1899 variable "i2cfast". (see also i2cfast) 1900 1901 CONFIG_I2C_MULTI_BUS 1902 1903 This option allows the use of multiple I2C buses, each of which 1904 must have a controller. At any point in time, only one bus is 1905 active. To switch to a different bus, use the 'i2c dev' command. 1906 Note that bus numbering is zero-based. 1907 1908 CONFIG_SYS_I2C_NOPROBES 1909 1910 This option specifies a list of I2C devices that will be skipped 1911 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1912 is set, specify a list of bus-device pairs. Otherwise, specify 1913 a 1D array of device addresses 1914 1915 e.g. 1916 #undef CONFIG_I2C_MULTI_BUS 1917 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1918 1919 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1920 1921 #define CONFIG_I2C_MULTI_BUS 1922 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1923 1924 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1925 1926 CONFIG_SYS_SPD_BUS_NUM 1927 1928 If defined, then this indicates the I2C bus number for DDR SPD. 1929 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1930 1931 CONFIG_SYS_RTC_BUS_NUM 1932 1933 If defined, then this indicates the I2C bus number for the RTC. 1934 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1935 1936 CONFIG_SYS_DTT_BUS_NUM 1937 1938 If defined, then this indicates the I2C bus number for the DTT. 1939 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1940 1941 CONFIG_SYS_I2C_DTT_ADDR: 1942 1943 If defined, specifies the I2C address of the DTT device. 1944 If not defined, then U-Boot uses predefined value for 1945 specified DTT device. 1946 1947 CONFIG_FSL_I2C 1948 1949 Define this option if you want to use Freescale's I2C driver in 1950 drivers/i2c/fsl_i2c.c. 1951 1952 CONFIG_I2C_MUX 1953 1954 Define this option if you have I2C devices reached over 1 .. n 1955 I2C Muxes like the pca9544a. This option addes a new I2C 1956 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a 1957 new I2C Bus to the existing I2C Busses. If you select the 1958 new Bus with "i2c dev", u-bbot sends first the commandos for 1959 the muxes to activate this new "bus". 1960 1961 CONFIG_I2C_MULTI_BUS must be also defined, to use this 1962 feature! 1963 1964 Example: 1965 Adding a new I2C Bus reached over 2 pca9544a muxes 1966 The First mux with address 70 and channel 6 1967 The Second mux with address 71 and channel 4 1968 1969 => i2c bus pca9544a:70:6:pca9544a:71:4 1970 1971 Use the "i2c bus" command without parameter, to get a list 1972 of I2C Busses with muxes: 1973 1974 => i2c bus 1975 Busses reached over muxes: 1976 Bus ID: 2 1977 reached over Mux(es): 1978 pca9544a@70 ch: 4 1979 Bus ID: 3 1980 reached over Mux(es): 1981 pca9544a@70 ch: 6 1982 pca9544a@71 ch: 4 1983 => 1984 1985 If you now switch to the new I2C Bus 3 with "i2c dev 3" 1986 u-boot first sends the command to the mux@70 to enable 1987 channel 6, and then the command to the mux@71 to enable 1988 the channel 4. 1989 1990 After that, you can use the "normal" i2c commands as 1991 usual to communicate with your I2C devices behind 1992 the 2 muxes. 1993 1994 This option is actually implemented for the bitbanging 1995 algorithm in common/soft_i2c.c and for the Hardware I2C 1996 Bus on the MPC8260. But it should be not so difficult 1997 to add this option to other architectures. 1998 1999 CONFIG_SOFT_I2C_READ_REPEATED_START 2000 2001 defining this will force the i2c_read() function in 2002 the soft_i2c driver to perform an I2C repeated start 2003 between writing the address pointer and reading the 2004 data. If this define is omitted the default behaviour 2005 of doing a stop-start sequence will be used. Most I2C 2006 devices can use either method, but some require one or 2007 the other. 2008 2009- SPI Support: CONFIG_SPI 2010 2011 Enables SPI driver (so far only tested with 2012 SPI EEPROM, also an instance works with Crystal A/D and 2013 D/As on the SACSng board) 2014 2015 CONFIG_SH_SPI 2016 2017 Enables the driver for SPI controller on SuperH. Currently 2018 only SH7757 is supported. 2019 2020 CONFIG_SPI_X 2021 2022 Enables extended (16-bit) SPI EEPROM addressing. 2023 (symmetrical to CONFIG_I2C_X) 2024 2025 CONFIG_SOFT_SPI 2026 2027 Enables a software (bit-bang) SPI driver rather than 2028 using hardware support. This is a general purpose 2029 driver that only requires three general I/O port pins 2030 (two outputs, one input) to function. If this is 2031 defined, the board configuration must define several 2032 SPI configuration items (port pins to use, etc). For 2033 an example, see include/configs/sacsng.h. 2034 2035 CONFIG_HARD_SPI 2036 2037 Enables a hardware SPI driver for general-purpose reads 2038 and writes. As with CONFIG_SOFT_SPI, the board configuration 2039 must define a list of chip-select function pointers. 2040 Currently supported on some MPC8xxx processors. For an 2041 example, see include/configs/mpc8349emds.h. 2042 2043 CONFIG_MXC_SPI 2044 2045 Enables the driver for the SPI controllers on i.MX and MXC 2046 SoCs. Currently i.MX31/35/51 are supported. 2047 2048- FPGA Support: CONFIG_FPGA 2049 2050 Enables FPGA subsystem. 2051 2052 CONFIG_FPGA_<vendor> 2053 2054 Enables support for specific chip vendors. 2055 (ALTERA, XILINX) 2056 2057 CONFIG_FPGA_<family> 2058 2059 Enables support for FPGA family. 2060 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2061 2062 CONFIG_FPGA_COUNT 2063 2064 Specify the number of FPGA devices to support. 2065 2066 CONFIG_SYS_FPGA_PROG_FEEDBACK 2067 2068 Enable printing of hash marks during FPGA configuration. 2069 2070 CONFIG_SYS_FPGA_CHECK_BUSY 2071 2072 Enable checks on FPGA configuration interface busy 2073 status by the configuration function. This option 2074 will require a board or device specific function to 2075 be written. 2076 2077 CONFIG_FPGA_DELAY 2078 2079 If defined, a function that provides delays in the FPGA 2080 configuration driver. 2081 2082 CONFIG_SYS_FPGA_CHECK_CTRLC 2083 Allow Control-C to interrupt FPGA configuration 2084 2085 CONFIG_SYS_FPGA_CHECK_ERROR 2086 2087 Check for configuration errors during FPGA bitfile 2088 loading. For example, abort during Virtex II 2089 configuration if the INIT_B line goes low (which 2090 indicated a CRC error). 2091 2092 CONFIG_SYS_FPGA_WAIT_INIT 2093 2094 Maximum time to wait for the INIT_B line to deassert 2095 after PROB_B has been deasserted during a Virtex II 2096 FPGA configuration sequence. The default time is 500 2097 ms. 2098 2099 CONFIG_SYS_FPGA_WAIT_BUSY 2100 2101 Maximum time to wait for BUSY to deassert during 2102 Virtex II FPGA configuration. The default is 5 ms. 2103 2104 CONFIG_SYS_FPGA_WAIT_CONFIG 2105 2106 Time to wait after FPGA configuration. The default is 2107 200 ms. 2108 2109- Configuration Management: 2110 CONFIG_IDENT_STRING 2111 2112 If defined, this string will be added to the U-Boot 2113 version information (U_BOOT_VERSION) 2114 2115- Vendor Parameter Protection: 2116 2117 U-Boot considers the values of the environment 2118 variables "serial#" (Board Serial Number) and 2119 "ethaddr" (Ethernet Address) to be parameters that 2120 are set once by the board vendor / manufacturer, and 2121 protects these variables from casual modification by 2122 the user. Once set, these variables are read-only, 2123 and write or delete attempts are rejected. You can 2124 change this behaviour: 2125 2126 If CONFIG_ENV_OVERWRITE is #defined in your config 2127 file, the write protection for vendor parameters is 2128 completely disabled. Anybody can change or delete 2129 these parameters. 2130 2131 Alternatively, if you #define _both_ CONFIG_ETHADDR 2132 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2133 Ethernet address is installed in the environment, 2134 which can be changed exactly ONCE by the user. [The 2135 serial# is unaffected by this, i. e. it remains 2136 read-only.] 2137 2138- Protected RAM: 2139 CONFIG_PRAM 2140 2141 Define this variable to enable the reservation of 2142 "protected RAM", i. e. RAM which is not overwritten 2143 by U-Boot. Define CONFIG_PRAM to hold the number of 2144 kB you want to reserve for pRAM. You can overwrite 2145 this default value by defining an environment 2146 variable "pram" to the number of kB you want to 2147 reserve. Note that the board info structure will 2148 still show the full amount of RAM. If pRAM is 2149 reserved, a new environment variable "mem" will 2150 automatically be defined to hold the amount of 2151 remaining RAM in a form that can be passed as boot 2152 argument to Linux, for instance like that: 2153 2154 setenv bootargs ... mem=\${mem} 2155 saveenv 2156 2157 This way you can tell Linux not to use this memory, 2158 either, which results in a memory region that will 2159 not be affected by reboots. 2160 2161 *WARNING* If your board configuration uses automatic 2162 detection of the RAM size, you must make sure that 2163 this memory test is non-destructive. So far, the 2164 following board configurations are known to be 2165 "pRAM-clean": 2166 2167 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 2168 HERMES, IP860, RPXlite, LWMON, LANTEC, 2169 FLAGADM, TQM8260 2170 2171- Error Recovery: 2172 CONFIG_PANIC_HANG 2173 2174 Define this variable to stop the system in case of a 2175 fatal error, so that you have to reset it manually. 2176 This is probably NOT a good idea for an embedded 2177 system where you want the system to reboot 2178 automatically as fast as possible, but it may be 2179 useful during development since you can try to debug 2180 the conditions that lead to the situation. 2181 2182 CONFIG_NET_RETRY_COUNT 2183 2184 This variable defines the number of retries for 2185 network operations like ARP, RARP, TFTP, or BOOTP 2186 before giving up the operation. If not defined, a 2187 default value of 5 is used. 2188 2189 CONFIG_ARP_TIMEOUT 2190 2191 Timeout waiting for an ARP reply in milliseconds. 2192 2193 CONFIG_NFS_TIMEOUT 2194 2195 Timeout in milliseconds used in NFS protocol. 2196 If you encounter "ERROR: Cannot umount" in nfs command, 2197 try longer timeout such as 2198 #define CONFIG_NFS_TIMEOUT 10000UL 2199 2200- Command Interpreter: 2201 CONFIG_AUTO_COMPLETE 2202 2203 Enable auto completion of commands using TAB. 2204 2205 Note that this feature has NOT been implemented yet 2206 for the "hush" shell. 2207 2208 2209 CONFIG_SYS_HUSH_PARSER 2210 2211 Define this variable to enable the "hush" shell (from 2212 Busybox) as command line interpreter, thus enabling 2213 powerful command line syntax like 2214 if...then...else...fi conditionals or `&&' and '||' 2215 constructs ("shell scripts"). 2216 2217 If undefined, you get the old, much simpler behaviour 2218 with a somewhat smaller memory footprint. 2219 2220 2221 CONFIG_SYS_PROMPT_HUSH_PS2 2222 2223 This defines the secondary prompt string, which is 2224 printed when the command interpreter needs more input 2225 to complete a command. Usually "> ". 2226 2227 Note: 2228 2229 In the current implementation, the local variables 2230 space and global environment variables space are 2231 separated. Local variables are those you define by 2232 simply typing `name=value'. To access a local 2233 variable later on, you have write `$name' or 2234 `${name}'; to execute the contents of a variable 2235 directly type `$name' at the command prompt. 2236 2237 Global environment variables are those you use 2238 setenv/printenv to work with. To run a command stored 2239 in such a variable, you need to use the run command, 2240 and you must not use the '$' sign to access them. 2241 2242 To store commands and special characters in a 2243 variable, please use double quotation marks 2244 surrounding the whole text of the variable, instead 2245 of the backslashes before semicolons and special 2246 symbols. 2247 2248- Commandline Editing and History: 2249 CONFIG_CMDLINE_EDITING 2250 2251 Enable editing and History functions for interactive 2252 commandline input operations 2253 2254- Default Environment: 2255 CONFIG_EXTRA_ENV_SETTINGS 2256 2257 Define this to contain any number of null terminated 2258 strings (variable = value pairs) that will be part of 2259 the default environment compiled into the boot image. 2260 2261 For example, place something like this in your 2262 board's config file: 2263 2264 #define CONFIG_EXTRA_ENV_SETTINGS \ 2265 "myvar1=value1\0" \ 2266 "myvar2=value2\0" 2267 2268 Warning: This method is based on knowledge about the 2269 internal format how the environment is stored by the 2270 U-Boot code. This is NOT an official, exported 2271 interface! Although it is unlikely that this format 2272 will change soon, there is no guarantee either. 2273 You better know what you are doing here. 2274 2275 Note: overly (ab)use of the default environment is 2276 discouraged. Make sure to check other ways to preset 2277 the environment like the "source" command or the 2278 boot command first. 2279 2280 CONFIG_ENV_VARS_UBOOT_CONFIG 2281 2282 Define this in order to add variables describing the 2283 U-Boot build configuration to the default environment. 2284 These will be named arch, cpu, board, vendor, and soc. 2285 2286 Enabling this option will cause the following to be defined: 2287 2288 - CONFIG_SYS_ARCH 2289 - CONFIG_SYS_CPU 2290 - CONFIG_SYS_BOARD 2291 - CONFIG_SYS_VENDOR 2292 - CONFIG_SYS_SOC 2293 2294- DataFlash Support: 2295 CONFIG_HAS_DATAFLASH 2296 2297 Defining this option enables DataFlash features and 2298 allows to read/write in Dataflash via the standard 2299 commands cp, md... 2300 2301- Serial Flash support 2302 CONFIG_CMD_SF 2303 2304 Defining this option enables SPI flash commands 2305 'sf probe/read/write/erase/update'. 2306 2307 Usage requires an initial 'probe' to define the serial 2308 flash parameters, followed by read/write/erase/update 2309 commands. 2310 2311 The following defaults may be provided by the platform 2312 to handle the common case when only a single serial 2313 flash is present on the system. 2314 2315 CONFIG_SF_DEFAULT_BUS Bus identifier 2316 CONFIG_SF_DEFAULT_CS Chip-select 2317 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2318 CONFIG_SF_DEFAULT_SPEED in Hz 2319 2320- SystemACE Support: 2321 CONFIG_SYSTEMACE 2322 2323 Adding this option adds support for Xilinx SystemACE 2324 chips attached via some sort of local bus. The address 2325 of the chip must also be defined in the 2326 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2327 2328 #define CONFIG_SYSTEMACE 2329 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2330 2331 When SystemACE support is added, the "ace" device type 2332 becomes available to the fat commands, i.e. fatls. 2333 2334- TFTP Fixed UDP Port: 2335 CONFIG_TFTP_PORT 2336 2337 If this is defined, the environment variable tftpsrcp 2338 is used to supply the TFTP UDP source port value. 2339 If tftpsrcp isn't defined, the normal pseudo-random port 2340 number generator is used. 2341 2342 Also, the environment variable tftpdstp is used to supply 2343 the TFTP UDP destination port value. If tftpdstp isn't 2344 defined, the normal port 69 is used. 2345 2346 The purpose for tftpsrcp is to allow a TFTP server to 2347 blindly start the TFTP transfer using the pre-configured 2348 target IP address and UDP port. This has the effect of 2349 "punching through" the (Windows XP) firewall, allowing 2350 the remainder of the TFTP transfer to proceed normally. 2351 A better solution is to properly configure the firewall, 2352 but sometimes that is not allowed. 2353 2354- Show boot progress: 2355 CONFIG_SHOW_BOOT_PROGRESS 2356 2357 Defining this option allows to add some board- 2358 specific code (calling a user-provided function 2359 "show_boot_progress(int)") that enables you to show 2360 the system's boot progress on some display (for 2361 example, some LED's) on your board. At the moment, 2362 the following checkpoints are implemented: 2363 2364- Detailed boot stage timing 2365 CONFIG_BOOTSTAGE 2366 Define this option to get detailed timing of each stage 2367 of the boot process. 2368 2369 CONFIG_BOOTSTAGE_USER_COUNT 2370 This is the number of available user bootstage records. 2371 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2372 a new ID will be allocated from this stash. If you exceed 2373 the limit, recording will stop. 2374 2375 CONFIG_BOOTSTAGE_REPORT 2376 Define this to print a report before boot, similar to this: 2377 2378 Timer summary in microseconds: 2379 Mark Elapsed Stage 2380 0 0 reset 2381 3,575,678 3,575,678 board_init_f start 2382 3,575,695 17 arch_cpu_init A9 2383 3,575,777 82 arch_cpu_init done 2384 3,659,598 83,821 board_init_r start 2385 3,910,375 250,777 main_loop 2386 29,916,167 26,005,792 bootm_start 2387 30,361,327 445,160 start_kernel 2388 2389Legacy uImage format: 2390 2391 Arg Where When 2392 1 common/cmd_bootm.c before attempting to boot an image 2393 -1 common/cmd_bootm.c Image header has bad magic number 2394 2 common/cmd_bootm.c Image header has correct magic number 2395 -2 common/cmd_bootm.c Image header has bad checksum 2396 3 common/cmd_bootm.c Image header has correct checksum 2397 -3 common/cmd_bootm.c Image data has bad checksum 2398 4 common/cmd_bootm.c Image data has correct checksum 2399 -4 common/cmd_bootm.c Image is for unsupported architecture 2400 5 common/cmd_bootm.c Architecture check OK 2401 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2402 6 common/cmd_bootm.c Image Type check OK 2403 -6 common/cmd_bootm.c gunzip uncompression error 2404 -7 common/cmd_bootm.c Unimplemented compression type 2405 7 common/cmd_bootm.c Uncompression OK 2406 8 common/cmd_bootm.c No uncompress/copy overwrite error 2407 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2408 2409 9 common/image.c Start initial ramdisk verification 2410 -10 common/image.c Ramdisk header has bad magic number 2411 -11 common/image.c Ramdisk header has bad checksum 2412 10 common/image.c Ramdisk header is OK 2413 -12 common/image.c Ramdisk data has bad checksum 2414 11 common/image.c Ramdisk data has correct checksum 2415 12 common/image.c Ramdisk verification complete, start loading 2416 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2417 13 common/image.c Start multifile image verification 2418 14 common/image.c No initial ramdisk, no multifile, continue. 2419 2420 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2421 2422 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2423 -31 post/post.c POST test failed, detected by post_output_backlog() 2424 -32 post/post.c POST test failed, detected by post_run_single() 2425 2426 34 common/cmd_doc.c before loading a Image from a DOC device 2427 -35 common/cmd_doc.c Bad usage of "doc" command 2428 35 common/cmd_doc.c correct usage of "doc" command 2429 -36 common/cmd_doc.c No boot device 2430 36 common/cmd_doc.c correct boot device 2431 -37 common/cmd_doc.c Unknown Chip ID on boot device 2432 37 common/cmd_doc.c correct chip ID found, device available 2433 -38 common/cmd_doc.c Read Error on boot device 2434 38 common/cmd_doc.c reading Image header from DOC device OK 2435 -39 common/cmd_doc.c Image header has bad magic number 2436 39 common/cmd_doc.c Image header has correct magic number 2437 -40 common/cmd_doc.c Error reading Image from DOC device 2438 40 common/cmd_doc.c Image header has correct magic number 2439 41 common/cmd_ide.c before loading a Image from a IDE device 2440 -42 common/cmd_ide.c Bad usage of "ide" command 2441 42 common/cmd_ide.c correct usage of "ide" command 2442 -43 common/cmd_ide.c No boot device 2443 43 common/cmd_ide.c boot device found 2444 -44 common/cmd_ide.c Device not available 2445 44 common/cmd_ide.c Device available 2446 -45 common/cmd_ide.c wrong partition selected 2447 45 common/cmd_ide.c partition selected 2448 -46 common/cmd_ide.c Unknown partition table 2449 46 common/cmd_ide.c valid partition table found 2450 -47 common/cmd_ide.c Invalid partition type 2451 47 common/cmd_ide.c correct partition type 2452 -48 common/cmd_ide.c Error reading Image Header on boot device 2453 48 common/cmd_ide.c reading Image Header from IDE device OK 2454 -49 common/cmd_ide.c Image header has bad magic number 2455 49 common/cmd_ide.c Image header has correct magic number 2456 -50 common/cmd_ide.c Image header has bad checksum 2457 50 common/cmd_ide.c Image header has correct checksum 2458 -51 common/cmd_ide.c Error reading Image from IDE device 2459 51 common/cmd_ide.c reading Image from IDE device OK 2460 52 common/cmd_nand.c before loading a Image from a NAND device 2461 -53 common/cmd_nand.c Bad usage of "nand" command 2462 53 common/cmd_nand.c correct usage of "nand" command 2463 -54 common/cmd_nand.c No boot device 2464 54 common/cmd_nand.c boot device found 2465 -55 common/cmd_nand.c Unknown Chip ID on boot device 2466 55 common/cmd_nand.c correct chip ID found, device available 2467 -56 common/cmd_nand.c Error reading Image Header on boot device 2468 56 common/cmd_nand.c reading Image Header from NAND device OK 2469 -57 common/cmd_nand.c Image header has bad magic number 2470 57 common/cmd_nand.c Image header has correct magic number 2471 -58 common/cmd_nand.c Error reading Image from NAND device 2472 58 common/cmd_nand.c reading Image from NAND device OK 2473 2474 -60 common/env_common.c Environment has a bad CRC, using default 2475 2476 64 net/eth.c starting with Ethernet configuration. 2477 -64 net/eth.c no Ethernet found. 2478 65 net/eth.c Ethernet found. 2479 2480 -80 common/cmd_net.c usage wrong 2481 80 common/cmd_net.c before calling NetLoop() 2482 -81 common/cmd_net.c some error in NetLoop() occurred 2483 81 common/cmd_net.c NetLoop() back without error 2484 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2485 82 common/cmd_net.c trying automatic boot 2486 83 common/cmd_net.c running "source" command 2487 -83 common/cmd_net.c some error in automatic boot or "source" command 2488 84 common/cmd_net.c end without errors 2489 2490FIT uImage format: 2491 2492 Arg Where When 2493 100 common/cmd_bootm.c Kernel FIT Image has correct format 2494 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2495 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2496 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2497 102 common/cmd_bootm.c Kernel unit name specified 2498 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2499 103 common/cmd_bootm.c Found configuration node 2500 104 common/cmd_bootm.c Got kernel subimage node offset 2501 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2502 105 common/cmd_bootm.c Kernel subimage hash verification OK 2503 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2504 106 common/cmd_bootm.c Architecture check OK 2505 -106 common/cmd_bootm.c Kernel subimage has wrong type 2506 107 common/cmd_bootm.c Kernel subimage type OK 2507 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2508 108 common/cmd_bootm.c Got kernel subimage data/size 2509 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2510 -109 common/cmd_bootm.c Can't get kernel subimage type 2511 -110 common/cmd_bootm.c Can't get kernel subimage comp 2512 -111 common/cmd_bootm.c Can't get kernel subimage os 2513 -112 common/cmd_bootm.c Can't get kernel subimage load address 2514 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2515 2516 120 common/image.c Start initial ramdisk verification 2517 -120 common/image.c Ramdisk FIT image has incorrect format 2518 121 common/image.c Ramdisk FIT image has correct format 2519 122 common/image.c No ramdisk subimage unit name, using configuration 2520 -122 common/image.c Can't get configuration for ramdisk subimage 2521 123 common/image.c Ramdisk unit name specified 2522 -124 common/image.c Can't get ramdisk subimage node offset 2523 125 common/image.c Got ramdisk subimage node offset 2524 -125 common/image.c Ramdisk subimage hash verification failed 2525 126 common/image.c Ramdisk subimage hash verification OK 2526 -126 common/image.c Ramdisk subimage for unsupported architecture 2527 127 common/image.c Architecture check OK 2528 -127 common/image.c Can't get ramdisk subimage data/size 2529 128 common/image.c Got ramdisk subimage data/size 2530 129 common/image.c Can't get ramdisk load address 2531 -129 common/image.c Got ramdisk load address 2532 2533 -130 common/cmd_doc.c Incorrect FIT image format 2534 131 common/cmd_doc.c FIT image format OK 2535 2536 -140 common/cmd_ide.c Incorrect FIT image format 2537 141 common/cmd_ide.c FIT image format OK 2538 2539 -150 common/cmd_nand.c Incorrect FIT image format 2540 151 common/cmd_nand.c FIT image format OK 2541 2542- Standalone program support: 2543 CONFIG_STANDALONE_LOAD_ADDR 2544 2545 This option defines a board specific value for the 2546 address where standalone program gets loaded, thus 2547 overwriting the architecture dependent default 2548 settings. 2549 2550- Frame Buffer Address: 2551 CONFIG_FB_ADDR 2552 2553 Define CONFIG_FB_ADDR if you want to use specific 2554 address for frame buffer. 2555 Then system will reserve the frame buffer address to 2556 defined address instead of lcd_setmem (this function 2557 grabs the memory for frame buffer by panel's size). 2558 2559 Please see board_init_f function. 2560 2561- Automatic software updates via TFTP server 2562 CONFIG_UPDATE_TFTP 2563 CONFIG_UPDATE_TFTP_CNT_MAX 2564 CONFIG_UPDATE_TFTP_MSEC_MAX 2565 2566 These options enable and control the auto-update feature; 2567 for a more detailed description refer to doc/README.update. 2568 2569- MTD Support (mtdparts command, UBI support) 2570 CONFIG_MTD_DEVICE 2571 2572 Adds the MTD device infrastructure from the Linux kernel. 2573 Needed for mtdparts command support. 2574 2575 CONFIG_MTD_PARTITIONS 2576 2577 Adds the MTD partitioning infrastructure from the Linux 2578 kernel. Needed for UBI support. 2579 2580- SPL framework 2581 CONFIG_SPL 2582 Enable building of SPL globally. 2583 2584 CONFIG_SPL_LDSCRIPT 2585 LDSCRIPT for linking the SPL binary. 2586 2587 CONFIG_SPL_MAX_SIZE 2588 Maximum binary size (text, data and rodata) of the SPL binary. 2589 2590 CONFIG_SPL_TEXT_BASE 2591 TEXT_BASE for linking the SPL binary. 2592 2593 CONFIG_SPL_BSS_START_ADDR 2594 Link address for the BSS within the SPL binary. 2595 2596 CONFIG_SPL_BSS_MAX_SIZE 2597 Maximum binary size of the BSS section of the SPL binary. 2598 2599 CONFIG_SPL_STACK 2600 Adress of the start of the stack SPL will use 2601 2602 CONFIG_SYS_SPL_MALLOC_START 2603 Starting address of the malloc pool used in SPL. 2604 2605 CONFIG_SYS_SPL_MALLOC_SIZE 2606 The size of the malloc pool used in SPL. 2607 2608 CONFIG_SPL_FRAMEWORK 2609 Enable the SPL framework under common/. This framework 2610 supports MMC, NAND and YMODEM loading of U-Boot and NAND 2611 NAND loading of the Linux Kernel. 2612 2613 CONFIG_SPL_DISPLAY_PRINT 2614 For ARM, enable an optional function to print more information 2615 about the running system. 2616 2617 CONFIG_SPL_LIBCOMMON_SUPPORT 2618 Support for common/libcommon.o in SPL binary 2619 2620 CONFIG_SPL_LIBDISK_SUPPORT 2621 Support for disk/libdisk.o in SPL binary 2622 2623 CONFIG_SPL_I2C_SUPPORT 2624 Support for drivers/i2c/libi2c.o in SPL binary 2625 2626 CONFIG_SPL_GPIO_SUPPORT 2627 Support for drivers/gpio/libgpio.o in SPL binary 2628 2629 CONFIG_SPL_MMC_SUPPORT 2630 Support for drivers/mmc/libmmc.o in SPL binary 2631 2632 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 2633 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 2634 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 2635 Address, size and partition on the MMC to load U-Boot from 2636 when the MMC is being used in raw mode. 2637 2638 CONFIG_SPL_FAT_SUPPORT 2639 Support for fs/fat/libfat.o in SPL binary 2640 2641 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 2642 Filename to read to load U-Boot when reading from FAT 2643 2644 CONFIG_SPL_NAND_SIMPLE 2645 Support for drivers/mtd/nand/libnand.o in SPL binary 2646 2647 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 2648 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 2649 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 2650 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 2651 CONFIG_SYS_NAND_ECCBYTES 2652 Defines the size and behavior of the NAND that SPL uses 2653 to read U-Boot with CONFIG_SPL_NAND_SIMPLE 2654 2655 CONFIG_SYS_NAND_U_BOOT_OFFS 2656 Location in NAND for CONFIG_SPL_NAND_SIMPLE to read U-Boot 2657 from. 2658 2659 CONFIG_SYS_NAND_U_BOOT_START 2660 Location in memory for CONFIG_SPL_NAND_SIMPLE to load U-Boot 2661 to. 2662 2663 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 2664 Define this if you need to first read the OOB and then the 2665 data. This is used for example on davinci plattforms. 2666 2667 CONFIG_SPL_OMAP3_ID_NAND 2668 Support for an OMAP3-specific set of functions to return the 2669 ID and MFR of the first attached NAND chip, if present. 2670 2671 CONFIG_SPL_SERIAL_SUPPORT 2672 Support for drivers/serial/libserial.o in SPL binary 2673 2674 CONFIG_SPL_SPI_FLASH_SUPPORT 2675 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 2676 2677 CONFIG_SPL_SPI_SUPPORT 2678 Support for drivers/spi/libspi.o in SPL binary 2679 2680 CONFIG_SPL_RAM_DEVICE 2681 Support for running image already present in ram, in SPL binary 2682 2683 CONFIG_SPL_LIBGENERIC_SUPPORT 2684 Support for lib/libgeneric.o in SPL binary 2685 2686Modem Support: 2687-------------- 2688 2689[so far only for SMDK2400 boards] 2690 2691- Modem support enable: 2692 CONFIG_MODEM_SUPPORT 2693 2694- RTS/CTS Flow control enable: 2695 CONFIG_HWFLOW 2696 2697- Modem debug support: 2698 CONFIG_MODEM_SUPPORT_DEBUG 2699 2700 Enables debugging stuff (char screen[1024], dbg()) 2701 for modem support. Useful only with BDI2000. 2702 2703- Interrupt support (PPC): 2704 2705 There are common interrupt_init() and timer_interrupt() 2706 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2707 for CPU specific initialization. interrupt_init_cpu() 2708 should set decrementer_count to appropriate value. If 2709 CPU resets decrementer automatically after interrupt 2710 (ppc4xx) it should set decrementer_count to zero. 2711 timer_interrupt() calls timer_interrupt_cpu() for CPU 2712 specific handling. If board has watchdog / status_led 2713 / other_activity_monitor it works automatically from 2714 general timer_interrupt(). 2715 2716- General: 2717 2718 In the target system modem support is enabled when a 2719 specific key (key combination) is pressed during 2720 power-on. Otherwise U-Boot will boot normally 2721 (autoboot). The key_pressed() function is called from 2722 board_init(). Currently key_pressed() is a dummy 2723 function, returning 1 and thus enabling modem 2724 initialization. 2725 2726 If there are no modem init strings in the 2727 environment, U-Boot proceed to autoboot; the 2728 previous output (banner, info printfs) will be 2729 suppressed, though. 2730 2731 See also: doc/README.Modem 2732 2733Board initialization settings: 2734------------------------------ 2735 2736During Initialization u-boot calls a number of board specific functions 2737to allow the preparation of board specific prerequisites, e.g. pin setup 2738before drivers are initialized. To enable these callbacks the 2739following configuration macros have to be defined. Currently this is 2740architecture specific, so please check arch/your_architecture/lib/board.c 2741typically in board_init_f() and board_init_r(). 2742 2743- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 2744- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 2745- CONFIG_BOARD_LATE_INIT: Call board_late_init() 2746- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 2747 2748Configuration Settings: 2749----------------------- 2750 2751- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2752 undefine this when you're short of memory. 2753 2754- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2755 width of the commands listed in the 'help' command output. 2756 2757- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2758 prompt for user input. 2759 2760- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2761 2762- CONFIG_SYS_PBSIZE: Buffer size for Console output 2763 2764- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2765 2766- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2767 the application (usually a Linux kernel) when it is 2768 booted 2769 2770- CONFIG_SYS_BAUDRATE_TABLE: 2771 List of legal baudrate settings for this board. 2772 2773- CONFIG_SYS_CONSOLE_INFO_QUIET 2774 Suppress display of console information at boot. 2775 2776- CONFIG_SYS_CONSOLE_IS_IN_ENV 2777 If the board specific function 2778 extern int overwrite_console (void); 2779 returns 1, the stdin, stderr and stdout are switched to the 2780 serial port, else the settings in the environment are used. 2781 2782- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 2783 Enable the call to overwrite_console(). 2784 2785- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 2786 Enable overwrite of previous console environment settings. 2787 2788- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2789 Begin and End addresses of the area used by the 2790 simple memory test. 2791 2792- CONFIG_SYS_ALT_MEMTEST: 2793 Enable an alternate, more extensive memory test. 2794 2795- CONFIG_SYS_MEMTEST_SCRATCH: 2796 Scratch address used by the alternate memory test 2797 You only need to set this if address zero isn't writeable 2798 2799- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 2800 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 2801 this specified memory area will get subtracted from the top 2802 (end) of RAM and won't get "touched" at all by U-Boot. By 2803 fixing up gd->ram_size the Linux kernel should gets passed 2804 the now "corrected" memory size and won't touch it either. 2805 This should work for arch/ppc and arch/powerpc. Only Linux 2806 board ports in arch/powerpc with bootwrapper support that 2807 recalculate the memory size from the SDRAM controller setup 2808 will have to get fixed in Linux additionally. 2809 2810 This option can be used as a workaround for the 440EPx/GRx 2811 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 2812 be touched. 2813 2814 WARNING: Please make sure that this value is a multiple of 2815 the Linux page size (normally 4k). If this is not the case, 2816 then the end address of the Linux memory will be located at a 2817 non page size aligned address and this could cause major 2818 problems. 2819 2820- CONFIG_SYS_TFTP_LOADADDR: 2821 Default load address for network file downloads 2822 2823- CONFIG_SYS_LOADS_BAUD_CHANGE: 2824 Enable temporary baudrate change while serial download 2825 2826- CONFIG_SYS_SDRAM_BASE: 2827 Physical start address of SDRAM. _Must_ be 0 here. 2828 2829- CONFIG_SYS_MBIO_BASE: 2830 Physical start address of Motherboard I/O (if using a 2831 Cogent motherboard) 2832 2833- CONFIG_SYS_FLASH_BASE: 2834 Physical start address of Flash memory. 2835 2836- CONFIG_SYS_MONITOR_BASE: 2837 Physical start address of boot monitor code (set by 2838 make config files to be same as the text base address 2839 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 2840 CONFIG_SYS_FLASH_BASE when booting from flash. 2841 2842- CONFIG_SYS_MONITOR_LEN: 2843 Size of memory reserved for monitor code, used to 2844 determine _at_compile_time_ (!) if the environment is 2845 embedded within the U-Boot image, or in a separate 2846 flash sector. 2847 2848- CONFIG_SYS_MALLOC_LEN: 2849 Size of DRAM reserved for malloc() use. 2850 2851- CONFIG_SYS_BOOTM_LEN: 2852 Normally compressed uImages are limited to an 2853 uncompressed size of 8 MBytes. If this is not enough, 2854 you can define CONFIG_SYS_BOOTM_LEN in your board config file 2855 to adjust this setting to your needs. 2856 2857- CONFIG_SYS_BOOTMAPSZ: 2858 Maximum size of memory mapped by the startup code of 2859 the Linux kernel; all data that must be processed by 2860 the Linux kernel (bd_info, boot arguments, FDT blob if 2861 used) must be put below this limit, unless "bootm_low" 2862 enviroment variable is defined and non-zero. In such case 2863 all data for the Linux kernel must be between "bootm_low" 2864 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 2865 variable "bootm_mapsize" will override the value of 2866 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 2867 then the value in "bootm_size" will be used instead. 2868 2869- CONFIG_SYS_BOOT_RAMDISK_HIGH: 2870 Enable initrd_high functionality. If defined then the 2871 initrd_high feature is enabled and the bootm ramdisk subcommand 2872 is enabled. 2873 2874- CONFIG_SYS_BOOT_GET_CMDLINE: 2875 Enables allocating and saving kernel cmdline in space between 2876 "bootm_low" and "bootm_low" + BOOTMAPSZ. 2877 2878- CONFIG_SYS_BOOT_GET_KBD: 2879 Enables allocating and saving a kernel copy of the bd_info in 2880 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 2881 2882- CONFIG_SYS_MAX_FLASH_BANKS: 2883 Max number of Flash memory banks 2884 2885- CONFIG_SYS_MAX_FLASH_SECT: 2886 Max number of sectors on a Flash chip 2887 2888- CONFIG_SYS_FLASH_ERASE_TOUT: 2889 Timeout for Flash erase operations (in ms) 2890 2891- CONFIG_SYS_FLASH_WRITE_TOUT: 2892 Timeout for Flash write operations (in ms) 2893 2894- CONFIG_SYS_FLASH_LOCK_TOUT 2895 Timeout for Flash set sector lock bit operation (in ms) 2896 2897- CONFIG_SYS_FLASH_UNLOCK_TOUT 2898 Timeout for Flash clear lock bits operation (in ms) 2899 2900- CONFIG_SYS_FLASH_PROTECTION 2901 If defined, hardware flash sectors protection is used 2902 instead of U-Boot software protection. 2903 2904- CONFIG_SYS_DIRECT_FLASH_TFTP: 2905 2906 Enable TFTP transfers directly to flash memory; 2907 without this option such a download has to be 2908 performed in two steps: (1) download to RAM, and (2) 2909 copy from RAM to flash. 2910 2911 The two-step approach is usually more reliable, since 2912 you can check if the download worked before you erase 2913 the flash, but in some situations (when system RAM is 2914 too limited to allow for a temporary copy of the 2915 downloaded image) this option may be very useful. 2916 2917- CONFIG_SYS_FLASH_CFI: 2918 Define if the flash driver uses extra elements in the 2919 common flash structure for storing flash geometry. 2920 2921- CONFIG_FLASH_CFI_DRIVER 2922 This option also enables the building of the cfi_flash driver 2923 in the drivers directory 2924 2925- CONFIG_FLASH_CFI_MTD 2926 This option enables the building of the cfi_mtd driver 2927 in the drivers directory. The driver exports CFI flash 2928 to the MTD layer. 2929 2930- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 2931 Use buffered writes to flash. 2932 2933- CONFIG_FLASH_SPANSION_S29WS_N 2934 s29ws-n MirrorBit flash has non-standard addresses for buffered 2935 write commands. 2936 2937- CONFIG_SYS_FLASH_QUIET_TEST 2938 If this option is defined, the common CFI flash doesn't 2939 print it's warning upon not recognized FLASH banks. This 2940 is useful, if some of the configured banks are only 2941 optionally available. 2942 2943- CONFIG_FLASH_SHOW_PROGRESS 2944 If defined (must be an integer), print out countdown 2945 digits and dots. Recommended value: 45 (9..1) for 80 2946 column displays, 15 (3..1) for 40 column displays. 2947 2948- CONFIG_SYS_RX_ETH_BUFFER: 2949 Defines the number of Ethernet receive buffers. On some 2950 Ethernet controllers it is recommended to set this value 2951 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2952 buffers can be full shortly after enabling the interface 2953 on high Ethernet traffic. 2954 Defaults to 4 if not defined. 2955 2956- CONFIG_ENV_MAX_ENTRIES 2957 2958 Maximum number of entries in the hash table that is used 2959 internally to store the environment settings. The default 2960 setting is supposed to be generous and should work in most 2961 cases. This setting can be used to tune behaviour; see 2962 lib/hashtable.c for details. 2963 2964The following definitions that deal with the placement and management 2965of environment data (variable area); in general, we support the 2966following configurations: 2967 2968- CONFIG_BUILD_ENVCRC: 2969 2970 Builds up envcrc with the target environment so that external utils 2971 may easily extract it and embed it in final U-Boot images. 2972 2973- CONFIG_ENV_IS_IN_FLASH: 2974 2975 Define this if the environment is in flash memory. 2976 2977 a) The environment occupies one whole flash sector, which is 2978 "embedded" in the text segment with the U-Boot code. This 2979 happens usually with "bottom boot sector" or "top boot 2980 sector" type flash chips, which have several smaller 2981 sectors at the start or the end. For instance, such a 2982 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2983 such a case you would place the environment in one of the 2984 4 kB sectors - with U-Boot code before and after it. With 2985 "top boot sector" type flash chips, you would put the 2986 environment in one of the last sectors, leaving a gap 2987 between U-Boot and the environment. 2988 2989 - CONFIG_ENV_OFFSET: 2990 2991 Offset of environment data (variable area) to the 2992 beginning of flash memory; for instance, with bottom boot 2993 type flash chips the second sector can be used: the offset 2994 for this sector is given here. 2995 2996 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 2997 2998 - CONFIG_ENV_ADDR: 2999 3000 This is just another way to specify the start address of 3001 the flash sector containing the environment (instead of 3002 CONFIG_ENV_OFFSET). 3003 3004 - CONFIG_ENV_SECT_SIZE: 3005 3006 Size of the sector containing the environment. 3007 3008 3009 b) Sometimes flash chips have few, equal sized, BIG sectors. 3010 In such a case you don't want to spend a whole sector for 3011 the environment. 3012 3013 - CONFIG_ENV_SIZE: 3014 3015 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3016 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3017 of this flash sector for the environment. This saves 3018 memory for the RAM copy of the environment. 3019 3020 It may also save flash memory if you decide to use this 3021 when your environment is "embedded" within U-Boot code, 3022 since then the remainder of the flash sector could be used 3023 for U-Boot code. It should be pointed out that this is 3024 STRONGLY DISCOURAGED from a robustness point of view: 3025 updating the environment in flash makes it always 3026 necessary to erase the WHOLE sector. If something goes 3027 wrong before the contents has been restored from a copy in 3028 RAM, your target system will be dead. 3029 3030 - CONFIG_ENV_ADDR_REDUND 3031 CONFIG_ENV_SIZE_REDUND 3032 3033 These settings describe a second storage area used to hold 3034 a redundant copy of the environment data, so that there is 3035 a valid backup copy in case there is a power failure during 3036 a "saveenv" operation. 3037 3038BE CAREFUL! Any changes to the flash layout, and some changes to the 3039source code will make it necessary to adapt <board>/u-boot.lds* 3040accordingly! 3041 3042 3043- CONFIG_ENV_IS_IN_NVRAM: 3044 3045 Define this if you have some non-volatile memory device 3046 (NVRAM, battery buffered SRAM) which you want to use for the 3047 environment. 3048 3049 - CONFIG_ENV_ADDR: 3050 - CONFIG_ENV_SIZE: 3051 3052 These two #defines are used to determine the memory area you 3053 want to use for environment. It is assumed that this memory 3054 can just be read and written to, without any special 3055 provision. 3056 3057BE CAREFUL! The first access to the environment happens quite early 3058in U-Boot initalization (when we try to get the setting of for the 3059console baudrate). You *MUST* have mapped your NVRAM area then, or 3060U-Boot will hang. 3061 3062Please note that even with NVRAM we still use a copy of the 3063environment in RAM: we could work on NVRAM directly, but we want to 3064keep settings there always unmodified except somebody uses "saveenv" 3065to save the current settings. 3066 3067 3068- CONFIG_ENV_IS_IN_EEPROM: 3069 3070 Use this if you have an EEPROM or similar serial access 3071 device and a driver for it. 3072 3073 - CONFIG_ENV_OFFSET: 3074 - CONFIG_ENV_SIZE: 3075 3076 These two #defines specify the offset and size of the 3077 environment area within the total memory of your EEPROM. 3078 3079 - CONFIG_SYS_I2C_EEPROM_ADDR: 3080 If defined, specified the chip address of the EEPROM device. 3081 The default address is zero. 3082 3083 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3084 If defined, the number of bits used to address bytes in a 3085 single page in the EEPROM device. A 64 byte page, for example 3086 would require six bits. 3087 3088 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3089 If defined, the number of milliseconds to delay between 3090 page writes. The default is zero milliseconds. 3091 3092 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3093 The length in bytes of the EEPROM memory array address. Note 3094 that this is NOT the chip address length! 3095 3096 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3097 EEPROM chips that implement "address overflow" are ones 3098 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3099 address and the extra bits end up in the "chip address" bit 3100 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3101 byte chips. 3102 3103 Note that we consider the length of the address field to 3104 still be one byte because the extra address bits are hidden 3105 in the chip address. 3106 3107 - CONFIG_SYS_EEPROM_SIZE: 3108 The size in bytes of the EEPROM device. 3109 3110 - CONFIG_ENV_EEPROM_IS_ON_I2C 3111 define this, if you have I2C and SPI activated, and your 3112 EEPROM, which holds the environment, is on the I2C bus. 3113 3114 - CONFIG_I2C_ENV_EEPROM_BUS 3115 if you have an Environment on an EEPROM reached over 3116 I2C muxes, you can define here, how to reach this 3117 EEPROM. For example: 3118 3119 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0" 3120 3121 EEPROM which holds the environment, is reached over 3122 a pca9547 i2c mux with address 0x70, channel 3. 3123 3124- CONFIG_ENV_IS_IN_DATAFLASH: 3125 3126 Define this if you have a DataFlash memory device which you 3127 want to use for the environment. 3128 3129 - CONFIG_ENV_OFFSET: 3130 - CONFIG_ENV_ADDR: 3131 - CONFIG_ENV_SIZE: 3132 3133 These three #defines specify the offset and size of the 3134 environment area within the total memory of your DataFlash placed 3135 at the specified address. 3136 3137- CONFIG_ENV_IS_IN_REMOTE: 3138 3139 Define this if you have a remote memory space which you 3140 want to use for the local device's environment. 3141 3142 - CONFIG_ENV_ADDR: 3143 - CONFIG_ENV_SIZE: 3144 3145 These two #defines specify the address and size of the 3146 environment area within the remote memory space. The 3147 local device can get the environment from remote memory 3148 space by SRIO or PCIE links. 3149 3150BE CAREFUL! For some special cases, the local device can not use 3151"saveenv" command. For example, the local device will get the 3152environment stored in a remote NOR flash by SRIO or PCIE link, 3153but it can not erase, write this NOR flash by SRIO or PCIE interface. 3154 3155- CONFIG_ENV_IS_IN_NAND: 3156 3157 Define this if you have a NAND device which you want to use 3158 for the environment. 3159 3160 - CONFIG_ENV_OFFSET: 3161 - CONFIG_ENV_SIZE: 3162 3163 These two #defines specify the offset and size of the environment 3164 area within the first NAND device. CONFIG_ENV_OFFSET must be 3165 aligned to an erase block boundary. 3166 3167 - CONFIG_ENV_OFFSET_REDUND (optional): 3168 3169 This setting describes a second storage area of CONFIG_ENV_SIZE 3170 size used to hold a redundant copy of the environment data, so 3171 that there is a valid backup copy in case there is a power failure 3172 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 3173 aligned to an erase block boundary. 3174 3175 - CONFIG_ENV_RANGE (optional): 3176 3177 Specifies the length of the region in which the environment 3178 can be written. This should be a multiple of the NAND device's 3179 block size. Specifying a range with more erase blocks than 3180 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3181 the range to be avoided. 3182 3183 - CONFIG_ENV_OFFSET_OOB (optional): 3184 3185 Enables support for dynamically retrieving the offset of the 3186 environment from block zero's out-of-band data. The 3187 "nand env.oob" command can be used to record this offset. 3188 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3189 using CONFIG_ENV_OFFSET_OOB. 3190 3191- CONFIG_NAND_ENV_DST 3192 3193 Defines address in RAM to which the nand_spl code should copy the 3194 environment. If redundant environment is used, it will be copied to 3195 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3196 3197- CONFIG_SYS_SPI_INIT_OFFSET 3198 3199 Defines offset to the initial SPI buffer area in DPRAM. The 3200 area is used at an early stage (ROM part) if the environment 3201 is configured to reside in the SPI EEPROM: We need a 520 byte 3202 scratch DPRAM area. It is used between the two initialization 3203 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 3204 to be a good choice since it makes it far enough from the 3205 start of the data area as well as from the stack pointer. 3206 3207Please note that the environment is read-only until the monitor 3208has been relocated to RAM and a RAM copy of the environment has been 3209created; also, when using EEPROM you will have to use getenv_f() 3210until then to read environment variables. 3211 3212The environment is protected by a CRC32 checksum. Before the monitor 3213is relocated into RAM, as a result of a bad CRC you will be working 3214with the compiled-in default environment - *silently*!!! [This is 3215necessary, because the first environment variable we need is the 3216"baudrate" setting for the console - if we have a bad CRC, we don't 3217have any device yet where we could complain.] 3218 3219Note: once the monitor has been relocated, then it will complain if 3220the default environment is used; a new CRC is computed as soon as you 3221use the "saveenv" command to store a valid environment. 3222 3223- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 3224 Echo the inverted Ethernet link state to the fault LED. 3225 3226 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 3227 also needs to be defined. 3228 3229- CONFIG_SYS_FAULT_MII_ADDR: 3230 MII address of the PHY to check for the Ethernet link state. 3231 3232- CONFIG_NS16550_MIN_FUNCTIONS: 3233 Define this if you desire to only have use of the NS16550_init 3234 and NS16550_putc functions for the serial driver located at 3235 drivers/serial/ns16550.c. This option is useful for saving 3236 space for already greatly restricted images, including but not 3237 limited to NAND_SPL configurations. 3238 3239Low Level (hardware related) configuration options: 3240--------------------------------------------------- 3241 3242- CONFIG_SYS_CACHELINE_SIZE: 3243 Cache Line Size of the CPU. 3244 3245- CONFIG_SYS_DEFAULT_IMMR: 3246 Default address of the IMMR after system reset. 3247 3248 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 3249 and RPXsuper) to be able to adjust the position of 3250 the IMMR register after a reset. 3251 3252- CONFIG_SYS_CCSRBAR_DEFAULT: 3253 Default (power-on reset) physical address of CCSR on Freescale 3254 PowerPC SOCs. 3255 3256- CONFIG_SYS_CCSRBAR: 3257 Virtual address of CCSR. On a 32-bit build, this is typically 3258 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3259 3260 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 3261 for cross-platform code that uses that macro instead. 3262 3263- CONFIG_SYS_CCSRBAR_PHYS: 3264 Physical address of CCSR. CCSR can be relocated to a new 3265 physical address, if desired. In this case, this macro should 3266 be set to that address. Otherwise, it should be set to the 3267 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3268 is typically relocated on 36-bit builds. It is recommended 3269 that this macro be defined via the _HIGH and _LOW macros: 3270 3271 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3272 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3273 3274- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3275 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3276 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3277 used in assembly code, so it must not contain typecasts or 3278 integer size suffixes (e.g. "ULL"). 3279 3280- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3281 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3282 used in assembly code, so it must not contain typecasts or 3283 integer size suffixes (e.g. "ULL"). 3284 3285- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3286 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3287 forced to a value that ensures that CCSR is not relocated. 3288 3289- Floppy Disk Support: 3290 CONFIG_SYS_FDC_DRIVE_NUMBER 3291 3292 the default drive number (default value 0) 3293 3294 CONFIG_SYS_ISA_IO_STRIDE 3295 3296 defines the spacing between FDC chipset registers 3297 (default value 1) 3298 3299 CONFIG_SYS_ISA_IO_OFFSET 3300 3301 defines the offset of register from address. It 3302 depends on which part of the data bus is connected to 3303 the FDC chipset. (default value 0) 3304 3305 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3306 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3307 default value. 3308 3309 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3310 fdc_hw_init() is called at the beginning of the FDC 3311 setup. fdc_hw_init() must be provided by the board 3312 source code. It is used to make hardware dependant 3313 initializations. 3314 3315- CONFIG_IDE_AHB: 3316 Most IDE controllers were designed to be connected with PCI 3317 interface. Only few of them were designed for AHB interface. 3318 When software is doing ATA command and data transfer to 3319 IDE devices through IDE-AHB controller, some additional 3320 registers accessing to these kind of IDE-AHB controller 3321 is requierd. 3322 3323- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3324 DO NOT CHANGE unless you know exactly what you're 3325 doing! (11-4) [MPC8xx/82xx systems only] 3326 3327- CONFIG_SYS_INIT_RAM_ADDR: 3328 3329 Start address of memory area that can be used for 3330 initial data and stack; please note that this must be 3331 writable memory that is working WITHOUT special 3332 initialization, i. e. you CANNOT use normal RAM which 3333 will become available only after programming the 3334 memory controller and running certain initialization 3335 sequences. 3336 3337 U-Boot uses the following memory types: 3338 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 3339 - MPC824X: data cache 3340 - PPC4xx: data cache 3341 3342- CONFIG_SYS_GBL_DATA_OFFSET: 3343 3344 Offset of the initial data structure in the memory 3345 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 3346 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 3347 data is located at the end of the available space 3348 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 3349 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 3350 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 3351 CONFIG_SYS_GBL_DATA_OFFSET) downward. 3352 3353 Note: 3354 On the MPC824X (or other systems that use the data 3355 cache for initial memory) the address chosen for 3356 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 3357 point to an otherwise UNUSED address space between 3358 the top of RAM and the start of the PCI space. 3359 3360- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 3361 3362- CONFIG_SYS_SYPCR: System Protection Control (11-9) 3363 3364- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 3365 3366- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 3367 3368- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 3369 3370- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 3371 3372- CONFIG_SYS_OR_TIMING_SDRAM: 3373 SDRAM timing 3374 3375- CONFIG_SYS_MAMR_PTA: 3376 periodic timer for refresh 3377 3378- CONFIG_SYS_DER: Debug Event Register (37-47) 3379 3380- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3381 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3382 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3383 CONFIG_SYS_BR1_PRELIM: 3384 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3385 3386- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3387 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3388 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3389 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3390 3391- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 3392 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 3393 Machine Mode Register and Memory Periodic Timer 3394 Prescaler definitions (SDRAM timing) 3395 3396- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 3397 enable I2C microcode relocation patch (MPC8xx); 3398 define relocation offset in DPRAM [DSP2] 3399 3400- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 3401 enable SMC microcode relocation patch (MPC8xx); 3402 define relocation offset in DPRAM [SMC1] 3403 3404- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 3405 enable SPI microcode relocation patch (MPC8xx); 3406 define relocation offset in DPRAM [SCC4] 3407 3408- CONFIG_SYS_USE_OSCCLK: 3409 Use OSCM clock mode on MBX8xx board. Be careful, 3410 wrong setting might damage your board. Read 3411 doc/README.MBX before setting this variable! 3412 3413- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 3414 Offset of the bootmode word in DPRAM used by post 3415 (Power On Self Tests). This definition overrides 3416 #define'd default value in commproc.h resp. 3417 cpm_8260.h. 3418 3419- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 3420 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 3421 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 3422 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 3423 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 3424 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 3425 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 3426 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 3427 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 3428 3429- CONFIG_PCI_DISABLE_PCIE: 3430 Disable PCI-Express on systems where it is supported but not 3431 required. 3432 3433- CONFIG_PCI_ENUM_ONLY 3434 Only scan through and get the devices on the busses. 3435 Don't do any setup work, presumably because someone or 3436 something has already done it, and we don't need to do it 3437 a second time. Useful for platforms that are pre-booted 3438 by coreboot or similar. 3439 3440- CONFIG_SYS_SRIO: 3441 Chip has SRIO or not 3442 3443- CONFIG_SRIO1: 3444 Board has SRIO 1 port available 3445 3446- CONFIG_SRIO2: 3447 Board has SRIO 2 port available 3448 3449- CONFIG_SYS_SRIOn_MEM_VIRT: 3450 Virtual Address of SRIO port 'n' memory region 3451 3452- CONFIG_SYS_SRIOn_MEM_PHYS: 3453 Physical Address of SRIO port 'n' memory region 3454 3455- CONFIG_SYS_SRIOn_MEM_SIZE: 3456 Size of SRIO port 'n' memory region 3457 3458- CONFIG_SYS_NDFC_16 3459 Defined to tell the NDFC that the NAND chip is using a 3460 16 bit bus. 3461 3462- CONFIG_SYS_NDFC_EBC0_CFG 3463 Sets the EBC0_CFG register for the NDFC. If not defined 3464 a default value will be used. 3465 3466- CONFIG_SPD_EEPROM 3467 Get DDR timing information from an I2C EEPROM. Common 3468 with pluggable memory modules such as SODIMMs 3469 3470 SPD_EEPROM_ADDRESS 3471 I2C address of the SPD EEPROM 3472 3473- CONFIG_SYS_SPD_BUS_NUM 3474 If SPD EEPROM is on an I2C bus other than the first 3475 one, specify here. Note that the value must resolve 3476 to something your driver can deal with. 3477 3478- CONFIG_SYS_DDR_RAW_TIMING 3479 Get DDR timing information from other than SPD. Common with 3480 soldered DDR chips onboard without SPD. DDR raw timing 3481 parameters are extracted from datasheet and hard-coded into 3482 header files or board specific files. 3483 3484- CONFIG_FSL_DDR_INTERACTIVE 3485 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3486 3487- CONFIG_SYS_83XX_DDR_USES_CS0 3488 Only for 83xx systems. If specified, then DDR should 3489 be configured using CS0 and CS1 instead of CS2 and CS3. 3490 3491- CONFIG_ETHER_ON_FEC[12] 3492 Define to enable FEC[12] on a 8xx series processor. 3493 3494- CONFIG_FEC[12]_PHY 3495 Define to the hardcoded PHY address which corresponds 3496 to the given FEC; i. e. 3497 #define CONFIG_FEC1_PHY 4 3498 means that the PHY with address 4 is connected to FEC1 3499 3500 When set to -1, means to probe for first available. 3501 3502- CONFIG_FEC[12]_PHY_NORXERR 3503 The PHY does not have a RXERR line (RMII only). 3504 (so program the FEC to ignore it). 3505 3506- CONFIG_RMII 3507 Enable RMII mode for all FECs. 3508 Note that this is a global option, we can't 3509 have one FEC in standard MII mode and another in RMII mode. 3510 3511- CONFIG_CRC32_VERIFY 3512 Add a verify option to the crc32 command. 3513 The syntax is: 3514 3515 => crc32 -v <address> <count> <crc32> 3516 3517 Where address/count indicate a memory area 3518 and crc32 is the correct crc32 which the 3519 area should have. 3520 3521- CONFIG_LOOPW 3522 Add the "loopw" memory command. This only takes effect if 3523 the memory commands are activated globally (CONFIG_CMD_MEM). 3524 3525- CONFIG_MX_CYCLIC 3526 Add the "mdc" and "mwc" memory commands. These are cyclic 3527 "md/mw" commands. 3528 Examples: 3529 3530 => mdc.b 10 4 500 3531 This command will print 4 bytes (10,11,12,13) each 500 ms. 3532 3533 => mwc.l 100 12345678 10 3534 This command will write 12345678 to address 100 all 10 ms. 3535 3536 This only takes effect if the memory commands are activated 3537 globally (CONFIG_CMD_MEM). 3538 3539- CONFIG_SKIP_LOWLEVEL_INIT 3540 [ARM, NDS32, MIPS only] If this variable is defined, then certain 3541 low level initializations (like setting up the memory 3542 controller) are omitted and/or U-Boot does not 3543 relocate itself into RAM. 3544 3545 Normally this variable MUST NOT be defined. The only 3546 exception is when U-Boot is loaded (to RAM) by some 3547 other boot loader or by a debugger which performs 3548 these initializations itself. 3549 3550- CONFIG_SPL_BUILD 3551 Modifies the behaviour of start.S when compiling a loader 3552 that is executed before the actual U-Boot. E.g. when 3553 compiling a NAND SPL. 3554 3555- CONFIG_USE_ARCH_MEMCPY 3556 CONFIG_USE_ARCH_MEMSET 3557 If these options are used a optimized version of memcpy/memset will 3558 be used if available. These functions may be faster under some 3559 conditions but may increase the binary size. 3560 3561Freescale QE/FMAN Firmware Support: 3562----------------------------------- 3563 3564The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 3565loading of "firmware", which is encoded in the QE firmware binary format. 3566This firmware often needs to be loaded during U-Boot booting, so macros 3567are used to identify the storage device (NOR flash, SPI, etc) and the address 3568within that device. 3569 3570- CONFIG_SYS_QE_FMAN_FW_ADDR 3571 The address in the storage device where the firmware is located. The 3572 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3573 is also specified. 3574 3575- CONFIG_SYS_QE_FMAN_FW_LENGTH 3576 The maximum possible size of the firmware. The firmware binary format 3577 has a field that specifies the actual size of the firmware, but it 3578 might not be possible to read any part of the firmware unless some 3579 local storage is allocated to hold the entire firmware first. 3580 3581- CONFIG_SYS_QE_FMAN_FW_IN_NOR 3582 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 3583 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 3584 virtual address in NOR flash. 3585 3586- CONFIG_SYS_QE_FMAN_FW_IN_NAND 3587 Specifies that QE/FMAN firmware is located in NAND flash. 3588 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 3589 3590- CONFIG_SYS_QE_FMAN_FW_IN_MMC 3591 Specifies that QE/FMAN firmware is located on the primary SD/MMC 3592 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3593 3594- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 3595 Specifies that QE/FMAN firmware is located on the primary SPI 3596 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3597 3598- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 3599 Specifies that QE/FMAN firmware is located in the remote (master) 3600 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 3601 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 3602 window->master inbound window->master LAW->the ucode address in 3603 master's memory space. 3604 3605Building the Software: 3606====================== 3607 3608Building U-Boot has been tested in several native build environments 3609and in many different cross environments. Of course we cannot support 3610all possibly existing versions of cross development tools in all 3611(potentially obsolete) versions. In case of tool chain problems we 3612recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3613which is extensively used to build and test U-Boot. 3614 3615If you are not using a native environment, it is assumed that you 3616have GNU cross compiling tools available in your path. In this case, 3617you must set the environment variable CROSS_COMPILE in your shell. 3618Note that no changes to the Makefile or any other source files are 3619necessary. For example using the ELDK on a 4xx CPU, please enter: 3620 3621 $ CROSS_COMPILE=ppc_4xx- 3622 $ export CROSS_COMPILE 3623 3624Note: If you wish to generate Windows versions of the utilities in 3625 the tools directory you can use the MinGW toolchain 3626 (http://www.mingw.org). Set your HOST tools to the MinGW 3627 toolchain and execute 'make tools'. For example: 3628 3629 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3630 3631 Binaries such as tools/mkimage.exe will be created which can 3632 be executed on computers running Windows. 3633 3634U-Boot is intended to be simple to build. After installing the 3635sources you must configure U-Boot for one specific board type. This 3636is done by typing: 3637 3638 make NAME_config 3639 3640where "NAME_config" is the name of one of the existing configu- 3641rations; see boards.cfg for supported names. 3642 3643Note: for some board special configuration names may exist; check if 3644 additional information is available from the board vendor; for 3645 instance, the TQM823L systems are available without (standard) 3646 or with LCD support. You can select such additional "features" 3647 when choosing the configuration, i. e. 3648 3649 make TQM823L_config 3650 - will configure for a plain TQM823L, i. e. no LCD support 3651 3652 make TQM823L_LCD_config 3653 - will configure for a TQM823L with U-Boot console on LCD 3654 3655 etc. 3656 3657 3658Finally, type "make all", and you should get some working U-Boot 3659images ready for download to / installation on your system: 3660 3661- "u-boot.bin" is a raw binary image 3662- "u-boot" is an image in ELF binary format 3663- "u-boot.srec" is in Motorola S-Record format 3664 3665By default the build is performed locally and the objects are saved 3666in the source directory. One of the two methods can be used to change 3667this behavior and build U-Boot to some external directory: 3668 36691. Add O= to the make command line invocations: 3670 3671 make O=/tmp/build distclean 3672 make O=/tmp/build NAME_config 3673 make O=/tmp/build all 3674 36752. Set environment variable BUILD_DIR to point to the desired location: 3676 3677 export BUILD_DIR=/tmp/build 3678 make distclean 3679 make NAME_config 3680 make all 3681 3682Note that the command line "O=" setting overrides the BUILD_DIR environment 3683variable. 3684 3685 3686Please be aware that the Makefiles assume you are using GNU make, so 3687for instance on NetBSD you might need to use "gmake" instead of 3688native "make". 3689 3690 3691If the system board that you have is not listed, then you will need 3692to port U-Boot to your hardware platform. To do this, follow these 3693steps: 3694 36951. Add a new configuration option for your board to the toplevel 3696 "boards.cfg" file, using the existing entries as examples. 3697 Follow the instructions there to keep the boards in order. 36982. Create a new directory to hold your board specific code. Add any 3699 files you need. In your board directory, you will need at least 3700 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 37013. Create a new configuration file "include/configs/<board>.h" for 3702 your board 37033. If you're porting U-Boot to a new CPU, then also create a new 3704 directory to hold your CPU specific code. Add any files you need. 37054. Run "make <board>_config" with your new name. 37065. Type "make", and you should get a working "u-boot.srec" file 3707 to be installed on your target system. 37086. Debug and solve any problems that might arise. 3709 [Of course, this last step is much harder than it sounds.] 3710 3711 3712Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3713============================================================== 3714 3715If you have modified U-Boot sources (for instance added a new board 3716or support for new devices, a new CPU, etc.) you are expected to 3717provide feedback to the other developers. The feedback normally takes 3718the form of a "patch", i. e. a context diff against a certain (latest 3719official or latest in the git repository) version of U-Boot sources. 3720 3721But before you submit such a patch, please verify that your modifi- 3722cation did not break existing code. At least make sure that *ALL* of 3723the supported boards compile WITHOUT ANY compiler warnings. To do so, 3724just run the "MAKEALL" script, which will configure and build U-Boot 3725for ALL supported system. Be warned, this will take a while. You can 3726select which (cross) compiler to use by passing a `CROSS_COMPILE' 3727environment variable to the script, i. e. to use the ELDK cross tools 3728you can type 3729 3730 CROSS_COMPILE=ppc_8xx- MAKEALL 3731 3732or to build on a native PowerPC system you can type 3733 3734 CROSS_COMPILE=' ' MAKEALL 3735 3736When using the MAKEALL script, the default behaviour is to build 3737U-Boot in the source directory. This location can be changed by 3738setting the BUILD_DIR environment variable. Also, for each target 3739built, the MAKEALL script saves two log files (<target>.ERR and 3740<target>.MAKEALL) in the <source dir>/LOG directory. This default 3741location can be changed by setting the MAKEALL_LOGDIR environment 3742variable. For example: 3743 3744 export BUILD_DIR=/tmp/build 3745 export MAKEALL_LOGDIR=/tmp/log 3746 CROSS_COMPILE=ppc_8xx- MAKEALL 3747 3748With the above settings build objects are saved in the /tmp/build, 3749log files are saved in the /tmp/log and the source tree remains clean 3750during the whole build process. 3751 3752 3753See also "U-Boot Porting Guide" below. 3754 3755 3756Monitor Commands - Overview: 3757============================ 3758 3759go - start application at address 'addr' 3760run - run commands in an environment variable 3761bootm - boot application image from memory 3762bootp - boot image via network using BootP/TFTP protocol 3763bootz - boot zImage from memory 3764tftpboot- boot image via network using TFTP protocol 3765 and env variables "ipaddr" and "serverip" 3766 (and eventually "gatewayip") 3767tftpput - upload a file via network using TFTP protocol 3768rarpboot- boot image via network using RARP/TFTP protocol 3769diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 3770loads - load S-Record file over serial line 3771loadb - load binary file over serial line (kermit mode) 3772md - memory display 3773mm - memory modify (auto-incrementing) 3774nm - memory modify (constant address) 3775mw - memory write (fill) 3776cp - memory copy 3777cmp - memory compare 3778crc32 - checksum calculation 3779i2c - I2C sub-system 3780sspi - SPI utility commands 3781base - print or set address offset 3782printenv- print environment variables 3783setenv - set environment variables 3784saveenv - save environment variables to persistent storage 3785protect - enable or disable FLASH write protection 3786erase - erase FLASH memory 3787flinfo - print FLASH memory information 3788bdinfo - print Board Info structure 3789iminfo - print header information for application image 3790coninfo - print console devices and informations 3791ide - IDE sub-system 3792loop - infinite loop on address range 3793loopw - infinite write loop on address range 3794mtest - simple RAM test 3795icache - enable or disable instruction cache 3796dcache - enable or disable data cache 3797reset - Perform RESET of the CPU 3798echo - echo args to console 3799version - print monitor version 3800help - print online help 3801? - alias for 'help' 3802 3803 3804Monitor Commands - Detailed Description: 3805======================================== 3806 3807TODO. 3808 3809For now: just type "help <command>". 3810 3811 3812Environment Variables: 3813====================== 3814 3815U-Boot supports user configuration using Environment Variables which 3816can be made persistent by saving to Flash memory. 3817 3818Environment Variables are set using "setenv", printed using 3819"printenv", and saved to Flash using "saveenv". Using "setenv" 3820without a value can be used to delete a variable from the 3821environment. As long as you don't save the environment you are 3822working with an in-memory copy. In case the Flash area containing the 3823environment is erased by accident, a default environment is provided. 3824 3825Some configuration options can be set using Environment Variables. 3826 3827List of environment variables (most likely not complete): 3828 3829 baudrate - see CONFIG_BAUDRATE 3830 3831 bootdelay - see CONFIG_BOOTDELAY 3832 3833 bootcmd - see CONFIG_BOOTCOMMAND 3834 3835 bootargs - Boot arguments when booting an RTOS image 3836 3837 bootfile - Name of the image to load with TFTP 3838 3839 bootm_low - Memory range available for image processing in the bootm 3840 command can be restricted. This variable is given as 3841 a hexadecimal number and defines lowest address allowed 3842 for use by the bootm command. See also "bootm_size" 3843 environment variable. Address defined by "bootm_low" is 3844 also the base of the initial memory mapping for the Linux 3845 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 3846 bootm_mapsize. 3847 3848 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 3849 This variable is given as a hexadecimal number and it 3850 defines the size of the memory region starting at base 3851 address bootm_low that is accessible by the Linux kernel 3852 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 3853 as the default value if it is defined, and bootm_size is 3854 used otherwise. 3855 3856 bootm_size - Memory range available for image processing in the bootm 3857 command can be restricted. This variable is given as 3858 a hexadecimal number and defines the size of the region 3859 allowed for use by the bootm command. See also "bootm_low" 3860 environment variable. 3861 3862 updatefile - Location of the software update file on a TFTP server, used 3863 by the automatic software update feature. Please refer to 3864 documentation in doc/README.update for more details. 3865 3866 autoload - if set to "no" (any string beginning with 'n'), 3867 "bootp" will just load perform a lookup of the 3868 configuration from the BOOTP server, but not try to 3869 load any image using TFTP 3870 3871 autostart - if set to "yes", an image loaded using the "bootp", 3872 "rarpboot", "tftpboot" or "diskboot" commands will 3873 be automatically started (by internally calling 3874 "bootm") 3875 3876 If set to "no", a standalone image passed to the 3877 "bootm" command will be copied to the load address 3878 (and eventually uncompressed), but NOT be started. 3879 This can be used to load and uncompress arbitrary 3880 data. 3881 3882 fdt_high - if set this restricts the maximum address that the 3883 flattened device tree will be copied into upon boot. 3884 For example, if you have a system with 1 GB memory 3885 at physical address 0x10000000, while Linux kernel 3886 only recognizes the first 704 MB as low memory, you 3887 may need to set fdt_high as 0x3C000000 to have the 3888 device tree blob be copied to the maximum address 3889 of the 704 MB low memory, so that Linux kernel can 3890 access it during the boot procedure. 3891 3892 If this is set to the special value 0xFFFFFFFF then 3893 the fdt will not be copied at all on boot. For this 3894 to work it must reside in writable memory, have 3895 sufficient padding on the end of it for u-boot to 3896 add the information it needs into it, and the memory 3897 must be accessible by the kernel. 3898 3899 fdtcontroladdr- if set this is the address of the control flattened 3900 device tree used by U-Boot when CONFIG_OF_CONTROL is 3901 defined. 3902 3903 i2cfast - (PPC405GP|PPC405EP only) 3904 if set to 'y' configures Linux I2C driver for fast 3905 mode (400kHZ). This environment variable is used in 3906 initialization code. So, for changes to be effective 3907 it must be saved and board must be reset. 3908 3909 initrd_high - restrict positioning of initrd images: 3910 If this variable is not set, initrd images will be 3911 copied to the highest possible address in RAM; this 3912 is usually what you want since it allows for 3913 maximum initrd size. If for some reason you want to 3914 make sure that the initrd image is loaded below the 3915 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 3916 variable to a value of "no" or "off" or "0". 3917 Alternatively, you can set it to a maximum upper 3918 address to use (U-Boot will still check that it 3919 does not overwrite the U-Boot stack and data). 3920 3921 For instance, when you have a system with 16 MB 3922 RAM, and want to reserve 4 MB from use by Linux, 3923 you can do this by adding "mem=12M" to the value of 3924 the "bootargs" variable. However, now you must make 3925 sure that the initrd image is placed in the first 3926 12 MB as well - this can be done with 3927 3928 setenv initrd_high 00c00000 3929 3930 If you set initrd_high to 0xFFFFFFFF, this is an 3931 indication to U-Boot that all addresses are legal 3932 for the Linux kernel, including addresses in flash 3933 memory. In this case U-Boot will NOT COPY the 3934 ramdisk at all. This may be useful to reduce the 3935 boot time on your system, but requires that this 3936 feature is supported by your Linux kernel. 3937 3938 ipaddr - IP address; needed for tftpboot command 3939 3940 loadaddr - Default load address for commands like "bootp", 3941 "rarpboot", "tftpboot", "loadb" or "diskboot" 3942 3943 loads_echo - see CONFIG_LOADS_ECHO 3944 3945 serverip - TFTP server IP address; needed for tftpboot command 3946 3947 bootretry - see CONFIG_BOOT_RETRY_TIME 3948 3949 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 3950 3951 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 3952 3953 ethprime - controls which interface is used first. 3954 3955 ethact - controls which interface is currently active. 3956 For example you can do the following 3957 3958 => setenv ethact FEC 3959 => ping 192.168.0.1 # traffic sent on FEC 3960 => setenv ethact SCC 3961 => ping 10.0.0.1 # traffic sent on SCC 3962 3963 ethrotate - When set to "no" U-Boot does not go through all 3964 available network interfaces. 3965 It just stays at the currently selected interface. 3966 3967 netretry - When set to "no" each network operation will 3968 either succeed or fail without retrying. 3969 When set to "once" the network operation will 3970 fail when all the available network interfaces 3971 are tried once without success. 3972 Useful on scripts which control the retry operation 3973 themselves. 3974 3975 npe_ucode - set load address for the NPE microcode 3976 3977 tftpsrcport - If this is set, the value is used for TFTP's 3978 UDP source port. 3979 3980 tftpdstport - If this is set, the value is used for TFTP's UDP 3981 destination port instead of the Well Know Port 69. 3982 3983 tftpblocksize - Block size to use for TFTP transfers; if not set, 3984 we use the TFTP server's default block size 3985 3986 tftptimeout - Retransmission timeout for TFTP packets (in milli- 3987 seconds, minimum value is 1000 = 1 second). Defines 3988 when a packet is considered to be lost so it has to 3989 be retransmitted. The default is 5000 = 5 seconds. 3990 Lowering this value may make downloads succeed 3991 faster in networks with high packet loss rates or 3992 with unreliable TFTP servers. 3993 3994 vlan - When set to a value < 4095 the traffic over 3995 Ethernet is encapsulated/received over 802.1q 3996 VLAN tagged frames. 3997 3998The following image location variables contain the location of images 3999used in booting. The "Image" column gives the role of the image and is 4000not an environment variable name. The other columns are environment 4001variable names. "File Name" gives the name of the file on a TFTP 4002server, "RAM Address" gives the location in RAM the image will be 4003loaded to, and "Flash Location" gives the image's address in NOR 4004flash or offset in NAND flash. 4005 4006*Note* - these variables don't have to be defined for all boards, some 4007boards currenlty use other variables for these purposes, and some 4008boards use these variables for other purposes. 4009 4010Image File Name RAM Address Flash Location 4011----- --------- ----------- -------------- 4012u-boot u-boot u-boot_addr_r u-boot_addr 4013Linux kernel bootfile kernel_addr_r kernel_addr 4014device tree blob fdtfile fdt_addr_r fdt_addr 4015ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4016 4017The following environment variables may be used and automatically 4018updated by the network boot commands ("bootp" and "rarpboot"), 4019depending the information provided by your boot server: 4020 4021 bootfile - see above 4022 dnsip - IP address of your Domain Name Server 4023 dnsip2 - IP address of your secondary Domain Name Server 4024 gatewayip - IP address of the Gateway (Router) to use 4025 hostname - Target hostname 4026 ipaddr - see above 4027 netmask - Subnet Mask 4028 rootpath - Pathname of the root filesystem on the NFS server 4029 serverip - see above 4030 4031 4032There are two special Environment Variables: 4033 4034 serial# - contains hardware identification information such 4035 as type string and/or serial number 4036 ethaddr - Ethernet address 4037 4038These variables can be set only once (usually during manufacturing of 4039the board). U-Boot refuses to delete or overwrite these variables 4040once they have been set once. 4041 4042 4043Further special Environment Variables: 4044 4045 ver - Contains the U-Boot version string as printed 4046 with the "version" command. This variable is 4047 readonly (see CONFIG_VERSION_VARIABLE). 4048 4049 4050Please note that changes to some configuration parameters may take 4051only effect after the next boot (yes, that's just like Windoze :-). 4052 4053 4054Command Line Parsing: 4055===================== 4056 4057There are two different command line parsers available with U-Boot: 4058the old "simple" one, and the much more powerful "hush" shell: 4059 4060Old, simple command line parser: 4061-------------------------------- 4062 4063- supports environment variables (through setenv / saveenv commands) 4064- several commands on one line, separated by ';' 4065- variable substitution using "... ${name} ..." syntax 4066- special characters ('$', ';') can be escaped by prefixing with '\', 4067 for example: 4068 setenv bootcmd bootm \${address} 4069- You can also escape text by enclosing in single apostrophes, for example: 4070 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4071 4072Hush shell: 4073----------- 4074 4075- similar to Bourne shell, with control structures like 4076 if...then...else...fi, for...do...done; while...do...done, 4077 until...do...done, ... 4078- supports environment ("global") variables (through setenv / saveenv 4079 commands) and local shell variables (through standard shell syntax 4080 "name=value"); only environment variables can be used with "run" 4081 command 4082 4083General rules: 4084-------------- 4085 4086(1) If a command line (or an environment variable executed by a "run" 4087 command) contains several commands separated by semicolon, and 4088 one of these commands fails, then the remaining commands will be 4089 executed anyway. 4090 4091(2) If you execute several variables with one call to run (i. e. 4092 calling run with a list of variables as arguments), any failing 4093 command will cause "run" to terminate, i. e. the remaining 4094 variables are not executed. 4095 4096Note for Redundant Ethernet Interfaces: 4097======================================= 4098 4099Some boards come with redundant Ethernet interfaces; U-Boot supports 4100such configurations and is capable of automatic selection of a 4101"working" interface when needed. MAC assignment works as follows: 4102 4103Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 4104MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 4105"eth1addr" (=>eth1), "eth2addr", ... 4106 4107If the network interface stores some valid MAC address (for instance 4108in SROM), this is used as default address if there is NO correspon- 4109ding setting in the environment; if the corresponding environment 4110variable is set, this overrides the settings in the card; that means: 4111 4112o If the SROM has a valid MAC address, and there is no address in the 4113 environment, the SROM's address is used. 4114 4115o If there is no valid address in the SROM, and a definition in the 4116 environment exists, then the value from the environment variable is 4117 used. 4118 4119o If both the SROM and the environment contain a MAC address, and 4120 both addresses are the same, this MAC address is used. 4121 4122o If both the SROM and the environment contain a MAC address, and the 4123 addresses differ, the value from the environment is used and a 4124 warning is printed. 4125 4126o If neither SROM nor the environment contain a MAC address, an error 4127 is raised. 4128 4129If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 4130will be programmed into hardware as part of the initialization process. This 4131may be skipped by setting the appropriate 'ethmacskip' environment variable. 4132The naming convention is as follows: 4133"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 4134 4135Image Formats: 4136============== 4137 4138U-Boot is capable of booting (and performing other auxiliary operations on) 4139images in two formats: 4140 4141New uImage format (FIT) 4142----------------------- 4143 4144Flexible and powerful format based on Flattened Image Tree -- FIT (similar 4145to Flattened Device Tree). It allows the use of images with multiple 4146components (several kernels, ramdisks, etc.), with contents protected by 4147SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 4148 4149 4150Old uImage format 4151----------------- 4152 4153Old image format is based on binary files which can be basically anything, 4154preceded by a special header; see the definitions in include/image.h for 4155details; basically, the header defines the following image properties: 4156 4157* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 4158 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 4159 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 4160 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 4161 INTEGRITY). 4162* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 4163 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 4164 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 4165* Compression Type (uncompressed, gzip, bzip2) 4166* Load Address 4167* Entry Point 4168* Image Name 4169* Image Timestamp 4170 4171The header is marked by a special Magic Number, and both the header 4172and the data portions of the image are secured against corruption by 4173CRC32 checksums. 4174 4175 4176Linux Support: 4177============== 4178 4179Although U-Boot should support any OS or standalone application 4180easily, the main focus has always been on Linux during the design of 4181U-Boot. 4182 4183U-Boot includes many features that so far have been part of some 4184special "boot loader" code within the Linux kernel. Also, any 4185"initrd" images to be used are no longer part of one big Linux image; 4186instead, kernel and "initrd" are separate images. This implementation 4187serves several purposes: 4188 4189- the same features can be used for other OS or standalone 4190 applications (for instance: using compressed images to reduce the 4191 Flash memory footprint) 4192 4193- it becomes much easier to port new Linux kernel versions because 4194 lots of low-level, hardware dependent stuff are done by U-Boot 4195 4196- the same Linux kernel image can now be used with different "initrd" 4197 images; of course this also means that different kernel images can 4198 be run with the same "initrd". This makes testing easier (you don't 4199 have to build a new "zImage.initrd" Linux image when you just 4200 change a file in your "initrd"). Also, a field-upgrade of the 4201 software is easier now. 4202 4203 4204Linux HOWTO: 4205============ 4206 4207Porting Linux to U-Boot based systems: 4208--------------------------------------- 4209 4210U-Boot cannot save you from doing all the necessary modifications to 4211configure the Linux device drivers for use with your target hardware 4212(no, we don't intend to provide a full virtual machine interface to 4213Linux :-). 4214 4215But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 4216 4217Just make sure your machine specific header file (for instance 4218include/asm-ppc/tqm8xx.h) includes the same definition of the Board 4219Information structure as we define in include/asm-<arch>/u-boot.h, 4220and make sure that your definition of IMAP_ADDR uses the same value 4221as your U-Boot configuration in CONFIG_SYS_IMMR. 4222 4223 4224Configuring the Linux kernel: 4225----------------------------- 4226 4227No specific requirements for U-Boot. Make sure you have some root 4228device (initial ramdisk, NFS) for your target system. 4229 4230 4231Building a Linux Image: 4232----------------------- 4233 4234With U-Boot, "normal" build targets like "zImage" or "bzImage" are 4235not used. If you use recent kernel source, a new build target 4236"uImage" will exist which automatically builds an image usable by 4237U-Boot. Most older kernels also have support for a "pImage" target, 4238which was introduced for our predecessor project PPCBoot and uses a 4239100% compatible format. 4240 4241Example: 4242 4243 make TQM850L_config 4244 make oldconfig 4245 make dep 4246 make uImage 4247 4248The "uImage" build target uses a special tool (in 'tools/mkimage') to 4249encapsulate a compressed Linux kernel image with header information, 4250CRC32 checksum etc. for use with U-Boot. This is what we are doing: 4251 4252* build a standard "vmlinux" kernel image (in ELF binary format): 4253 4254* convert the kernel into a raw binary image: 4255 4256 ${CROSS_COMPILE}-objcopy -O binary \ 4257 -R .note -R .comment \ 4258 -S vmlinux linux.bin 4259 4260* compress the binary image: 4261 4262 gzip -9 linux.bin 4263 4264* package compressed binary image for U-Boot: 4265 4266 mkimage -A ppc -O linux -T kernel -C gzip \ 4267 -a 0 -e 0 -n "Linux Kernel Image" \ 4268 -d linux.bin.gz uImage 4269 4270 4271The "mkimage" tool can also be used to create ramdisk images for use 4272with U-Boot, either separated from the Linux kernel image, or 4273combined into one file. "mkimage" encapsulates the images with a 64 4274byte header containing information about target architecture, 4275operating system, image type, compression method, entry points, time 4276stamp, CRC32 checksums, etc. 4277 4278"mkimage" can be called in two ways: to verify existing images and 4279print the header information, or to build new images. 4280 4281In the first form (with "-l" option) mkimage lists the information 4282contained in the header of an existing U-Boot image; this includes 4283checksum verification: 4284 4285 tools/mkimage -l image 4286 -l ==> list image header information 4287 4288The second form (with "-d" option) is used to build a U-Boot image 4289from a "data file" which is used as image payload: 4290 4291 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 4292 -n name -d data_file image 4293 -A ==> set architecture to 'arch' 4294 -O ==> set operating system to 'os' 4295 -T ==> set image type to 'type' 4296 -C ==> set compression type 'comp' 4297 -a ==> set load address to 'addr' (hex) 4298 -e ==> set entry point to 'ep' (hex) 4299 -n ==> set image name to 'name' 4300 -d ==> use image data from 'datafile' 4301 4302Right now, all Linux kernels for PowerPC systems use the same load 4303address (0x00000000), but the entry point address depends on the 4304kernel version: 4305 4306- 2.2.x kernels have the entry point at 0x0000000C, 4307- 2.3.x and later kernels have the entry point at 0x00000000. 4308 4309So a typical call to build a U-Boot image would read: 4310 4311 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4312 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 4313 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 4314 > examples/uImage.TQM850L 4315 Image Name: 2.4.4 kernel for TQM850L 4316 Created: Wed Jul 19 02:34:59 2000 4317 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4318 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4319 Load Address: 0x00000000 4320 Entry Point: 0x00000000 4321 4322To verify the contents of the image (or check for corruption): 4323 4324 -> tools/mkimage -l examples/uImage.TQM850L 4325 Image Name: 2.4.4 kernel for TQM850L 4326 Created: Wed Jul 19 02:34:59 2000 4327 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4328 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4329 Load Address: 0x00000000 4330 Entry Point: 0x00000000 4331 4332NOTE: for embedded systems where boot time is critical you can trade 4333speed for memory and install an UNCOMPRESSED image instead: this 4334needs more space in Flash, but boots much faster since it does not 4335need to be uncompressed: 4336 4337 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 4338 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4339 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 4340 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 4341 > examples/uImage.TQM850L-uncompressed 4342 Image Name: 2.4.4 kernel for TQM850L 4343 Created: Wed Jul 19 02:34:59 2000 4344 Image Type: PowerPC Linux Kernel Image (uncompressed) 4345 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 4346 Load Address: 0x00000000 4347 Entry Point: 0x00000000 4348 4349 4350Similar you can build U-Boot images from a 'ramdisk.image.gz' file 4351when your kernel is intended to use an initial ramdisk: 4352 4353 -> tools/mkimage -n 'Simple Ramdisk Image' \ 4354 > -A ppc -O linux -T ramdisk -C gzip \ 4355 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 4356 Image Name: Simple Ramdisk Image 4357 Created: Wed Jan 12 14:01:50 2000 4358 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4359 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 4360 Load Address: 0x00000000 4361 Entry Point: 0x00000000 4362 4363 4364Installing a Linux Image: 4365------------------------- 4366 4367To downloading a U-Boot image over the serial (console) interface, 4368you must convert the image to S-Record format: 4369 4370 objcopy -I binary -O srec examples/image examples/image.srec 4371 4372The 'objcopy' does not understand the information in the U-Boot 4373image header, so the resulting S-Record file will be relative to 4374address 0x00000000. To load it to a given address, you need to 4375specify the target address as 'offset' parameter with the 'loads' 4376command. 4377 4378Example: install the image to address 0x40100000 (which on the 4379TQM8xxL is in the first Flash bank): 4380 4381 => erase 40100000 401FFFFF 4382 4383 .......... done 4384 Erased 8 sectors 4385 4386 => loads 40100000 4387 ## Ready for S-Record download ... 4388 ~>examples/image.srec 4389 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 4390 ... 4391 15989 15990 15991 15992 4392 [file transfer complete] 4393 [connected] 4394 ## Start Addr = 0x00000000 4395 4396 4397You can check the success of the download using the 'iminfo' command; 4398this includes a checksum verification so you can be sure no data 4399corruption happened: 4400 4401 => imi 40100000 4402 4403 ## Checking Image at 40100000 ... 4404 Image Name: 2.2.13 for initrd on TQM850L 4405 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4406 Data Size: 335725 Bytes = 327 kB = 0 MB 4407 Load Address: 00000000 4408 Entry Point: 0000000c 4409 Verifying Checksum ... OK 4410 4411 4412Boot Linux: 4413----------- 4414 4415The "bootm" command is used to boot an application that is stored in 4416memory (RAM or Flash). In case of a Linux kernel image, the contents 4417of the "bootargs" environment variable is passed to the kernel as 4418parameters. You can check and modify this variable using the 4419"printenv" and "setenv" commands: 4420 4421 4422 => printenv bootargs 4423 bootargs=root=/dev/ram 4424 4425 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4426 4427 => printenv bootargs 4428 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4429 4430 => bootm 40020000 4431 ## Booting Linux kernel at 40020000 ... 4432 Image Name: 2.2.13 for NFS on TQM850L 4433 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4434 Data Size: 381681 Bytes = 372 kB = 0 MB 4435 Load Address: 00000000 4436 Entry Point: 0000000c 4437 Verifying Checksum ... OK 4438 Uncompressing Kernel Image ... OK 4439 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 4440 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4441 time_init: decrementer frequency = 187500000/60 4442 Calibrating delay loop... 49.77 BogoMIPS 4443 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4444 ... 4445 4446If you want to boot a Linux kernel with initial RAM disk, you pass 4447the memory addresses of both the kernel and the initrd image (PPBCOOT 4448format!) to the "bootm" command: 4449 4450 => imi 40100000 40200000 4451 4452 ## Checking Image at 40100000 ... 4453 Image Name: 2.2.13 for initrd on TQM850L 4454 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4455 Data Size: 335725 Bytes = 327 kB = 0 MB 4456 Load Address: 00000000 4457 Entry Point: 0000000c 4458 Verifying Checksum ... OK 4459 4460 ## Checking Image at 40200000 ... 4461 Image Name: Simple Ramdisk Image 4462 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4463 Data Size: 566530 Bytes = 553 kB = 0 MB 4464 Load Address: 00000000 4465 Entry Point: 00000000 4466 Verifying Checksum ... OK 4467 4468 => bootm 40100000 40200000 4469 ## Booting Linux kernel at 40100000 ... 4470 Image Name: 2.2.13 for initrd on TQM850L 4471 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4472 Data Size: 335725 Bytes = 327 kB = 0 MB 4473 Load Address: 00000000 4474 Entry Point: 0000000c 4475 Verifying Checksum ... OK 4476 Uncompressing Kernel Image ... OK 4477 ## Loading RAMDisk Image at 40200000 ... 4478 Image Name: Simple Ramdisk Image 4479 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4480 Data Size: 566530 Bytes = 553 kB = 0 MB 4481 Load Address: 00000000 4482 Entry Point: 00000000 4483 Verifying Checksum ... OK 4484 Loading Ramdisk ... OK 4485 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 4486 Boot arguments: root=/dev/ram 4487 time_init: decrementer frequency = 187500000/60 4488 Calibrating delay loop... 49.77 BogoMIPS 4489 ... 4490 RAMDISK: Compressed image found at block 0 4491 VFS: Mounted root (ext2 filesystem). 4492 4493 bash# 4494 4495Boot Linux and pass a flat device tree: 4496----------- 4497 4498First, U-Boot must be compiled with the appropriate defines. See the section 4499titled "Linux Kernel Interface" above for a more in depth explanation. The 4500following is an example of how to start a kernel and pass an updated 4501flat device tree: 4502 4503=> print oftaddr 4504oftaddr=0x300000 4505=> print oft 4506oft=oftrees/mpc8540ads.dtb 4507=> tftp $oftaddr $oft 4508Speed: 1000, full duplex 4509Using TSEC0 device 4510TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4511Filename 'oftrees/mpc8540ads.dtb'. 4512Load address: 0x300000 4513Loading: # 4514done 4515Bytes transferred = 4106 (100a hex) 4516=> tftp $loadaddr $bootfile 4517Speed: 1000, full duplex 4518Using TSEC0 device 4519TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4520Filename 'uImage'. 4521Load address: 0x200000 4522Loading:############ 4523done 4524Bytes transferred = 1029407 (fb51f hex) 4525=> print loadaddr 4526loadaddr=200000 4527=> print oftaddr 4528oftaddr=0x300000 4529=> bootm $loadaddr - $oftaddr 4530## Booting image at 00200000 ... 4531 Image Name: Linux-2.6.17-dirty 4532 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4533 Data Size: 1029343 Bytes = 1005.2 kB 4534 Load Address: 00000000 4535 Entry Point: 00000000 4536 Verifying Checksum ... OK 4537 Uncompressing Kernel Image ... OK 4538Booting using flat device tree at 0x300000 4539Using MPC85xx ADS machine description 4540Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4541[snip] 4542 4543 4544More About U-Boot Image Types: 4545------------------------------ 4546 4547U-Boot supports the following image types: 4548 4549 "Standalone Programs" are directly runnable in the environment 4550 provided by U-Boot; it is expected that (if they behave 4551 well) you can continue to work in U-Boot after return from 4552 the Standalone Program. 4553 "OS Kernel Images" are usually images of some Embedded OS which 4554 will take over control completely. Usually these programs 4555 will install their own set of exception handlers, device 4556 drivers, set up the MMU, etc. - this means, that you cannot 4557 expect to re-enter U-Boot except by resetting the CPU. 4558 "RAMDisk Images" are more or less just data blocks, and their 4559 parameters (address, size) are passed to an OS kernel that is 4560 being started. 4561 "Multi-File Images" contain several images, typically an OS 4562 (Linux) kernel image and one or more data images like 4563 RAMDisks. This construct is useful for instance when you want 4564 to boot over the network using BOOTP etc., where the boot 4565 server provides just a single image file, but you want to get 4566 for instance an OS kernel and a RAMDisk image. 4567 4568 "Multi-File Images" start with a list of image sizes, each 4569 image size (in bytes) specified by an "uint32_t" in network 4570 byte order. This list is terminated by an "(uint32_t)0". 4571 Immediately after the terminating 0 follow the images, one by 4572 one, all aligned on "uint32_t" boundaries (size rounded up to 4573 a multiple of 4 bytes). 4574 4575 "Firmware Images" are binary images containing firmware (like 4576 U-Boot or FPGA images) which usually will be programmed to 4577 flash memory. 4578 4579 "Script files" are command sequences that will be executed by 4580 U-Boot's command interpreter; this feature is especially 4581 useful when you configure U-Boot to use a real shell (hush) 4582 as command interpreter. 4583 4584Booting the Linux zImage: 4585------------------------- 4586 4587On some platforms, it's possible to boot Linux zImage. This is done 4588using the "bootz" command. The syntax of "bootz" command is the same 4589as the syntax of "bootm" command. 4590 4591Note, defining the CONFIG_SUPPORT_INITRD_RAW allows user to supply 4592kernel with raw initrd images. The syntax is slightly different, the 4593address of the initrd must be augmented by it's size, in the following 4594format: "<initrd addres>:<initrd size>". 4595 4596 4597Standalone HOWTO: 4598================= 4599 4600One of the features of U-Boot is that you can dynamically load and 4601run "standalone" applications, which can use some resources of 4602U-Boot like console I/O functions or interrupt services. 4603 4604Two simple examples are included with the sources: 4605 4606"Hello World" Demo: 4607------------------- 4608 4609'examples/hello_world.c' contains a small "Hello World" Demo 4610application; it is automatically compiled when you build U-Boot. 4611It's configured to run at address 0x00040004, so you can play with it 4612like that: 4613 4614 => loads 4615 ## Ready for S-Record download ... 4616 ~>examples/hello_world.srec 4617 1 2 3 4 5 6 7 8 9 10 11 ... 4618 [file transfer complete] 4619 [connected] 4620 ## Start Addr = 0x00040004 4621 4622 => go 40004 Hello World! This is a test. 4623 ## Starting application at 0x00040004 ... 4624 Hello World 4625 argc = 7 4626 argv[0] = "40004" 4627 argv[1] = "Hello" 4628 argv[2] = "World!" 4629 argv[3] = "This" 4630 argv[4] = "is" 4631 argv[5] = "a" 4632 argv[6] = "test." 4633 argv[7] = "<NULL>" 4634 Hit any key to exit ... 4635 4636 ## Application terminated, rc = 0x0 4637 4638Another example, which demonstrates how to register a CPM interrupt 4639handler with the U-Boot code, can be found in 'examples/timer.c'. 4640Here, a CPM timer is set up to generate an interrupt every second. 4641The interrupt service routine is trivial, just printing a '.' 4642character, but this is just a demo program. The application can be 4643controlled by the following keys: 4644 4645 ? - print current values og the CPM Timer registers 4646 b - enable interrupts and start timer 4647 e - stop timer and disable interrupts 4648 q - quit application 4649 4650 => loads 4651 ## Ready for S-Record download ... 4652 ~>examples/timer.srec 4653 1 2 3 4 5 6 7 8 9 10 11 ... 4654 [file transfer complete] 4655 [connected] 4656 ## Start Addr = 0x00040004 4657 4658 => go 40004 4659 ## Starting application at 0x00040004 ... 4660 TIMERS=0xfff00980 4661 Using timer 1 4662 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4663 4664Hit 'b': 4665 [q, b, e, ?] Set interval 1000000 us 4666 Enabling timer 4667Hit '?': 4668 [q, b, e, ?] ........ 4669 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4670Hit '?': 4671 [q, b, e, ?] . 4672 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4673Hit '?': 4674 [q, b, e, ?] . 4675 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4676Hit '?': 4677 [q, b, e, ?] . 4678 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4679Hit 'e': 4680 [q, b, e, ?] ...Stopping timer 4681Hit 'q': 4682 [q, b, e, ?] ## Application terminated, rc = 0x0 4683 4684 4685Minicom warning: 4686================ 4687 4688Over time, many people have reported problems when trying to use the 4689"minicom" terminal emulation program for serial download. I (wd) 4690consider minicom to be broken, and recommend not to use it. Under 4691Unix, I recommend to use C-Kermit for general purpose use (and 4692especially for kermit binary protocol download ("loadb" command), and 4693use "cu" for S-Record download ("loads" command). See 4694http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 4695for help with kermit. 4696 4697 4698Nevertheless, if you absolutely want to use it try adding this 4699configuration to your "File transfer protocols" section: 4700 4701 Name Program Name U/D FullScr IO-Red. Multi 4702 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 4703 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 4704 4705 4706NetBSD Notes: 4707============= 4708 4709Starting at version 0.9.2, U-Boot supports NetBSD both as host 4710(build U-Boot) and target system (boots NetBSD/mpc8xx). 4711 4712Building requires a cross environment; it is known to work on 4713NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 4714need gmake since the Makefiles are not compatible with BSD make). 4715Note that the cross-powerpc package does not install include files; 4716attempting to build U-Boot will fail because <machine/ansi.h> is 4717missing. This file has to be installed and patched manually: 4718 4719 # cd /usr/pkg/cross/powerpc-netbsd/include 4720 # mkdir powerpc 4721 # ln -s powerpc machine 4722 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 4723 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 4724 4725Native builds *don't* work due to incompatibilities between native 4726and U-Boot include files. 4727 4728Booting assumes that (the first part of) the image booted is a 4729stage-2 loader which in turn loads and then invokes the kernel 4730proper. Loader sources will eventually appear in the NetBSD source 4731tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 4732meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 4733 4734 4735Implementation Internals: 4736========================= 4737 4738The following is not intended to be a complete description of every 4739implementation detail. However, it should help to understand the 4740inner workings of U-Boot and make it easier to port it to custom 4741hardware. 4742 4743 4744Initial Stack, Global Data: 4745--------------------------- 4746 4747The implementation of U-Boot is complicated by the fact that U-Boot 4748starts running out of ROM (flash memory), usually without access to 4749system RAM (because the memory controller is not initialized yet). 4750This means that we don't have writable Data or BSS segments, and BSS 4751is not initialized as zero. To be able to get a C environment working 4752at all, we have to allocate at least a minimal stack. Implementation 4753options for this are defined and restricted by the CPU used: Some CPU 4754models provide on-chip memory (like the IMMR area on MPC8xx and 4755MPC826x processors), on others (parts of) the data cache can be 4756locked as (mis-) used as memory, etc. 4757 4758 Chris Hallinan posted a good summary of these issues to the 4759 U-Boot mailing list: 4760 4761 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 4762 From: "Chris Hallinan" <clh@net1plus.com> 4763 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 4764 ... 4765 4766 Correct me if I'm wrong, folks, but the way I understand it 4767 is this: Using DCACHE as initial RAM for Stack, etc, does not 4768 require any physical RAM backing up the cache. The cleverness 4769 is that the cache is being used as a temporary supply of 4770 necessary storage before the SDRAM controller is setup. It's 4771 beyond the scope of this list to explain the details, but you 4772 can see how this works by studying the cache architecture and 4773 operation in the architecture and processor-specific manuals. 4774 4775 OCM is On Chip Memory, which I believe the 405GP has 4K. It 4776 is another option for the system designer to use as an 4777 initial stack/RAM area prior to SDRAM being available. Either 4778 option should work for you. Using CS 4 should be fine if your 4779 board designers haven't used it for something that would 4780 cause you grief during the initial boot! It is frequently not 4781 used. 4782 4783 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 4784 with your processor/board/system design. The default value 4785 you will find in any recent u-boot distribution in 4786 walnut.h should work for you. I'd set it to a value larger 4787 than your SDRAM module. If you have a 64MB SDRAM module, set 4788 it above 400_0000. Just make sure your board has no resources 4789 that are supposed to respond to that address! That code in 4790 start.S has been around a while and should work as is when 4791 you get the config right. 4792 4793 -Chris Hallinan 4794 DS4.COM, Inc. 4795 4796It is essential to remember this, since it has some impact on the C 4797code for the initialization procedures: 4798 4799* Initialized global data (data segment) is read-only. Do not attempt 4800 to write it. 4801 4802* Do not use any uninitialized global data (or implicitely initialized 4803 as zero data - BSS segment) at all - this is undefined, initiali- 4804 zation is performed later (when relocating to RAM). 4805 4806* Stack space is very limited. Avoid big data buffers or things like 4807 that. 4808 4809Having only the stack as writable memory limits means we cannot use 4810normal global data to share information beween the code. But it 4811turned out that the implementation of U-Boot can be greatly 4812simplified by making a global data structure (gd_t) available to all 4813functions. We could pass a pointer to this data as argument to _all_ 4814functions, but this would bloat the code. Instead we use a feature of 4815the GCC compiler (Global Register Variables) to share the data: we 4816place a pointer (gd) to the global data into a register which we 4817reserve for this purpose. 4818 4819When choosing a register for such a purpose we are restricted by the 4820relevant (E)ABI specifications for the current architecture, and by 4821GCC's implementation. 4822 4823For PowerPC, the following registers have specific use: 4824 R1: stack pointer 4825 R2: reserved for system use 4826 R3-R4: parameter passing and return values 4827 R5-R10: parameter passing 4828 R13: small data area pointer 4829 R30: GOT pointer 4830 R31: frame pointer 4831 4832 (U-Boot also uses R12 as internal GOT pointer. r12 4833 is a volatile register so r12 needs to be reset when 4834 going back and forth between asm and C) 4835 4836 ==> U-Boot will use R2 to hold a pointer to the global data 4837 4838 Note: on PPC, we could use a static initializer (since the 4839 address of the global data structure is known at compile time), 4840 but it turned out that reserving a register results in somewhat 4841 smaller code - although the code savings are not that big (on 4842 average for all boards 752 bytes for the whole U-Boot image, 4843 624 text + 127 data). 4844 4845On Blackfin, the normal C ABI (except for P3) is followed as documented here: 4846 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 4847 4848 ==> U-Boot will use P3 to hold a pointer to the global data 4849 4850On ARM, the following registers are used: 4851 4852 R0: function argument word/integer result 4853 R1-R3: function argument word 4854 R9: GOT pointer 4855 R10: stack limit (used only if stack checking if enabled) 4856 R11: argument (frame) pointer 4857 R12: temporary workspace 4858 R13: stack pointer 4859 R14: link register 4860 R15: program counter 4861 4862 ==> U-Boot will use R8 to hold a pointer to the global data 4863 4864On Nios II, the ABI is documented here: 4865 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 4866 4867 ==> U-Boot will use gp to hold a pointer to the global data 4868 4869 Note: on Nios II, we give "-G0" option to gcc and don't use gp 4870 to access small data sections, so gp is free. 4871 4872On NDS32, the following registers are used: 4873 4874 R0-R1: argument/return 4875 R2-R5: argument 4876 R15: temporary register for assembler 4877 R16: trampoline register 4878 R28: frame pointer (FP) 4879 R29: global pointer (GP) 4880 R30: link register (LP) 4881 R31: stack pointer (SP) 4882 PC: program counter (PC) 4883 4884 ==> U-Boot will use R10 to hold a pointer to the global data 4885 4886NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 4887or current versions of GCC may "optimize" the code too much. 4888 4889Memory Management: 4890------------------ 4891 4892U-Boot runs in system state and uses physical addresses, i.e. the 4893MMU is not used either for address mapping nor for memory protection. 4894 4895The available memory is mapped to fixed addresses using the memory 4896controller. In this process, a contiguous block is formed for each 4897memory type (Flash, SDRAM, SRAM), even when it consists of several 4898physical memory banks. 4899 4900U-Boot is installed in the first 128 kB of the first Flash bank (on 4901TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 4902booting and sizing and initializing DRAM, the code relocates itself 4903to the upper end of DRAM. Immediately below the U-Boot code some 4904memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 4905configuration setting]. Below that, a structure with global Board 4906Info data is placed, followed by the stack (growing downward). 4907 4908Additionally, some exception handler code is copied to the low 8 kB 4909of DRAM (0x00000000 ... 0x00001FFF). 4910 4911So a typical memory configuration with 16 MB of DRAM could look like 4912this: 4913 4914 0x0000 0000 Exception Vector code 4915 : 4916 0x0000 1FFF 4917 0x0000 2000 Free for Application Use 4918 : 4919 : 4920 4921 : 4922 : 4923 0x00FB FF20 Monitor Stack (Growing downward) 4924 0x00FB FFAC Board Info Data and permanent copy of global data 4925 0x00FC 0000 Malloc Arena 4926 : 4927 0x00FD FFFF 4928 0x00FE 0000 RAM Copy of Monitor Code 4929 ... eventually: LCD or video framebuffer 4930 ... eventually: pRAM (Protected RAM - unchanged by reset) 4931 0x00FF FFFF [End of RAM] 4932 4933 4934System Initialization: 4935---------------------- 4936 4937In the reset configuration, U-Boot starts at the reset entry point 4938(on most PowerPC systems at address 0x00000100). Because of the reset 4939configuration for CS0# this is a mirror of the onboard Flash memory. 4940To be able to re-map memory U-Boot then jumps to its link address. 4941To be able to implement the initialization code in C, a (small!) 4942initial stack is set up in the internal Dual Ported RAM (in case CPUs 4943which provide such a feature like MPC8xx or MPC8260), or in a locked 4944part of the data cache. After that, U-Boot initializes the CPU core, 4945the caches and the SIU. 4946 4947Next, all (potentially) available memory banks are mapped using a 4948preliminary mapping. For example, we put them on 512 MB boundaries 4949(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 4950on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 4951programmed for SDRAM access. Using the temporary configuration, a 4952simple memory test is run that determines the size of the SDRAM 4953banks. 4954 4955When there is more than one SDRAM bank, and the banks are of 4956different size, the largest is mapped first. For equal size, the first 4957bank (CS2#) is mapped first. The first mapping is always for address 49580x00000000, with any additional banks following immediately to create 4959contiguous memory starting from 0. 4960 4961Then, the monitor installs itself at the upper end of the SDRAM area 4962and allocates memory for use by malloc() and for the global Board 4963Info data; also, the exception vector code is copied to the low RAM 4964pages, and the final stack is set up. 4965 4966Only after this relocation will you have a "normal" C environment; 4967until that you are restricted in several ways, mostly because you are 4968running from ROM, and because the code will have to be relocated to a 4969new address in RAM. 4970 4971 4972U-Boot Porting Guide: 4973---------------------- 4974 4975[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 4976list, October 2002] 4977 4978 4979int main(int argc, char *argv[]) 4980{ 4981 sighandler_t no_more_time; 4982 4983 signal(SIGALRM, no_more_time); 4984 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 4985 4986 if (available_money > available_manpower) { 4987 Pay consultant to port U-Boot; 4988 return 0; 4989 } 4990 4991 Download latest U-Boot source; 4992 4993 Subscribe to u-boot mailing list; 4994 4995 if (clueless) 4996 email("Hi, I am new to U-Boot, how do I get started?"); 4997 4998 while (learning) { 4999 Read the README file in the top level directory; 5000 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5001 Read applicable doc/*.README; 5002 Read the source, Luke; 5003 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5004 } 5005 5006 if (available_money > toLocalCurrency ($2500)) 5007 Buy a BDI3000; 5008 else 5009 Add a lot of aggravation and time; 5010 5011 if (a similar board exists) { /* hopefully... */ 5012 cp -a board/<similar> board/<myboard> 5013 cp include/configs/<similar>.h include/configs/<myboard>.h 5014 } else { 5015 Create your own board support subdirectory; 5016 Create your own board include/configs/<myboard>.h file; 5017 } 5018 Edit new board/<myboard> files 5019 Edit new include/configs/<myboard>.h 5020 5021 while (!accepted) { 5022 while (!running) { 5023 do { 5024 Add / modify source code; 5025 } until (compiles); 5026 Debug; 5027 if (clueless) 5028 email("Hi, I am having problems..."); 5029 } 5030 Send patch file to the U-Boot email list; 5031 if (reasonable critiques) 5032 Incorporate improvements from email list code review; 5033 else 5034 Defend code as written; 5035 } 5036 5037 return 0; 5038} 5039 5040void no_more_time (int sig) 5041{ 5042 hire_a_guru(); 5043} 5044 5045 5046Coding Standards: 5047----------------- 5048 5049All contributions to U-Boot should conform to the Linux kernel 5050coding style; see the file "Documentation/CodingStyle" and the script 5051"scripts/Lindent" in your Linux kernel source directory. 5052 5053Source files originating from a different project (for example the 5054MTD subsystem) are generally exempt from these guidelines and are not 5055reformated to ease subsequent migration to newer versions of those 5056sources. 5057 5058Please note that U-Boot is implemented in C (and to some small parts in 5059Assembler); no C++ is used, so please do not use C++ style comments (//) 5060in your code. 5061 5062Please also stick to the following formatting rules: 5063- remove any trailing white space 5064- use TAB characters for indentation and vertical alignment, not spaces 5065- make sure NOT to use DOS '\r\n' line feeds 5066- do not add more than 2 consecutive empty lines to source files 5067- do not add trailing empty lines to source files 5068 5069Submissions which do not conform to the standards may be returned 5070with a request to reformat the changes. 5071 5072 5073Submitting Patches: 5074------------------- 5075 5076Since the number of patches for U-Boot is growing, we need to 5077establish some rules. Submissions which do not conform to these rules 5078may be rejected, even when they contain important and valuable stuff. 5079 5080Please see http://www.denx.de/wiki/U-Boot/Patches for details. 5081 5082Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 5083see http://lists.denx.de/mailman/listinfo/u-boot 5084 5085When you send a patch, please include the following information with 5086it: 5087 5088* For bug fixes: a description of the bug and how your patch fixes 5089 this bug. Please try to include a way of demonstrating that the 5090 patch actually fixes something. 5091 5092* For new features: a description of the feature and your 5093 implementation. 5094 5095* A CHANGELOG entry as plaintext (separate from the patch) 5096 5097* For major contributions, your entry to the CREDITS file 5098 5099* When you add support for a new board, don't forget to add this 5100 board to the MAINTAINERS file, too. 5101 5102* If your patch adds new configuration options, don't forget to 5103 document these in the README file. 5104 5105* The patch itself. If you are using git (which is *strongly* 5106 recommended) you can easily generate the patch using the 5107 "git format-patch". If you then use "git send-email" to send it to 5108 the U-Boot mailing list, you will avoid most of the common problems 5109 with some other mail clients. 5110 5111 If you cannot use git, use "diff -purN OLD NEW". If your version of 5112 diff does not support these options, then get the latest version of 5113 GNU diff. 5114 5115 The current directory when running this command shall be the parent 5116 directory of the U-Boot source tree (i. e. please make sure that 5117 your patch includes sufficient directory information for the 5118 affected files). 5119 5120 We prefer patches as plain text. MIME attachments are discouraged, 5121 and compressed attachments must not be used. 5122 5123* If one logical set of modifications affects or creates several 5124 files, all these changes shall be submitted in a SINGLE patch file. 5125 5126* Changesets that contain different, unrelated modifications shall be 5127 submitted as SEPARATE patches, one patch per changeset. 5128 5129 5130Notes: 5131 5132* Before sending the patch, run the MAKEALL script on your patched 5133 source tree and make sure that no errors or warnings are reported 5134 for any of the boards. 5135 5136* Keep your modifications to the necessary minimum: A patch 5137 containing several unrelated changes or arbitrary reformats will be 5138 returned with a request to re-formatting / split it. 5139 5140* If you modify existing code, make sure that your new code does not 5141 add to the memory footprint of the code ;-) Small is beautiful! 5142 When adding new features, these should compile conditionally only 5143 (using #ifdef), and the resulting code with the new feature 5144 disabled must not need more memory than the old code without your 5145 modification. 5146 5147* Remember that there is a size limit of 100 kB per message on the 5148 u-boot mailing list. Bigger patches will be moderated. If they are 5149 reasonable and not too big, they will be acknowledged. But patches 5150 bigger than the size limit should be avoided. 5151