1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG file to find out who contributed 38the specific port. In addition, there are various MAINTAINERS files 39scattered throughout the U-Boot source identifying the people or 40companies responsible for various boards and subsystems. 41 42Note: As of August, 2010, there is no longer a CHANGELOG file in the 43actual U-Boot source tree; however, it can be created dynamically 44from the Git log using: 45 46 make CHANGELOG 47 48 49Where to get help: 50================== 51 52In case you have questions about, problems with or contributions for 53U-Boot, you should send a message to the U-Boot mailing list at 54<u-boot@lists.denx.de>. There is also an archive of previous traffic 55on the mailing list - please search the archive before asking FAQ's. 56Please see http://lists.denx.de/pipermail/u-boot and 57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 58 59 60Where to get source code: 61========================= 62 63The U-Boot source code is maintained in the Git repository at 64git://www.denx.de/git/u-boot.git ; you can browse it online at 65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 66 67The "snapshot" links on this page allow you to download tarballs of 68any version you might be interested in. Official releases are also 69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 70directory. 71 72Pre-built (and tested) images are available from 73ftp://ftp.denx.de/pub/u-boot/images/ 74 75 76Where we come from: 77=================== 78 79- start from 8xxrom sources 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 81- clean up code 82- make it easier to add custom boards 83- make it possible to add other [PowerPC] CPUs 84- extend functions, especially: 85 * Provide extended interface to Linux boot loader 86 * S-Record download 87 * network boot 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 89- create ARMBoot project (http://sourceforge.net/projects/armboot) 90- add other CPU families (starting with ARM) 91- create U-Boot project (http://sourceforge.net/projects/u-boot) 92- current project page: see http://www.denx.de/wiki/U-Boot 93 94 95Names and Spelling: 96=================== 97 98The "official" name of this project is "Das U-Boot". The spelling 99"U-Boot" shall be used in all written text (documentation, comments 100in source files etc.). Example: 101 102 This is the README file for the U-Boot project. 103 104File names etc. shall be based on the string "u-boot". Examples: 105 106 include/asm-ppc/u-boot.h 107 108 #include <asm/u-boot.h> 109 110Variable names, preprocessor constants etc. shall be either based on 111the string "u_boot" or on "U_BOOT". Example: 112 113 U_BOOT_VERSION u_boot_logo 114 IH_OS_U_BOOT u_boot_hush_start 115 116 117Versioning: 118=========== 119 120Starting with the release in October 2008, the names of the releases 121were changed from numerical release numbers without deeper meaning 122into a time stamp based numbering. Regular releases are identified by 123names consisting of the calendar year and month of the release date. 124Additional fields (if present) indicate release candidates or bug fix 125releases in "stable" maintenance trees. 126 127Examples: 128 U-Boot v2009.11 - Release November 2009 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 130 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release 131 132 133Directory Hierarchy: 134==================== 135 136/arch Architecture specific files 137 /arc Files generic to ARC architecture 138 /arm Files generic to ARM architecture 139 /m68k Files generic to m68k architecture 140 /microblaze Files generic to microblaze architecture 141 /mips Files generic to MIPS architecture 142 /nds32 Files generic to NDS32 architecture 143 /nios2 Files generic to Altera NIOS2 architecture 144 /openrisc Files generic to OpenRISC architecture 145 /powerpc Files generic to PowerPC architecture 146 /riscv Files generic to RISC-V architecture 147 /sandbox Files generic to HW-independent "sandbox" 148 /sh Files generic to SH architecture 149 /x86 Files generic to x86 architecture 150/api Machine/arch independent API for external apps 151/board Board dependent files 152/cmd U-Boot commands functions 153/common Misc architecture independent functions 154/configs Board default configuration files 155/disk Code for disk drive partition handling 156/doc Documentation (don't expect too much) 157/drivers Commonly used device drivers 158/dts Contains Makefile for building internal U-Boot fdt. 159/examples Example code for standalone applications, etc. 160/fs Filesystem code (cramfs, ext2, jffs2, etc.) 161/include Header Files 162/lib Library routines generic to all architectures 163/Licenses Various license files 164/net Networking code 165/post Power On Self Test 166/scripts Various build scripts and Makefiles 167/test Various unit test files 168/tools Tools to build S-Record or U-Boot images, etc. 169 170Software Configuration: 171======================= 172 173Configuration is usually done using C preprocessor defines; the 174rationale behind that is to avoid dead code whenever possible. 175 176There are two classes of configuration variables: 177 178* Configuration _OPTIONS_: 179 These are selectable by the user and have names beginning with 180 "CONFIG_". 181 182* Configuration _SETTINGS_: 183 These depend on the hardware etc. and should not be meddled with if 184 you don't know what you're doing; they have names beginning with 185 "CONFIG_SYS_". 186 187Previously, all configuration was done by hand, which involved creating 188symbolic links and editing configuration files manually. More recently, 189U-Boot has added the Kbuild infrastructure used by the Linux kernel, 190allowing you to use the "make menuconfig" command to configure your 191build. 192 193 194Selection of Processor Architecture and Board Type: 195--------------------------------------------------- 196 197For all supported boards there are ready-to-use default 198configurations available; just type "make <board_name>_defconfig". 199 200Example: For a TQM823L module type: 201 202 cd u-boot 203 make TQM823L_defconfig 204 205Note: If you're looking for the default configuration file for a board 206you're sure used to be there but is now missing, check the file 207doc/README.scrapyard for a list of no longer supported boards. 208 209Sandbox Environment: 210-------------------- 211 212U-Boot can be built natively to run on a Linux host using the 'sandbox' 213board. This allows feature development which is not board- or architecture- 214specific to be undertaken on a native platform. The sandbox is also used to 215run some of U-Boot's tests. 216 217See board/sandbox/README.sandbox for more details. 218 219 220Board Initialisation Flow: 221-------------------------- 222 223This is the intended start-up flow for boards. This should apply for both 224SPL and U-Boot proper (i.e. they both follow the same rules). 225 226Note: "SPL" stands for "Secondary Program Loader," which is explained in 227more detail later in this file. 228 229At present, SPL mostly uses a separate code path, but the function names 230and roles of each function are the same. Some boards or architectures 231may not conform to this. At least most ARM boards which use 232CONFIG_SPL_FRAMEWORK conform to this. 233 234Execution typically starts with an architecture-specific (and possibly 235CPU-specific) start.S file, such as: 236 237 - arch/arm/cpu/armv7/start.S 238 - arch/powerpc/cpu/mpc83xx/start.S 239 - arch/mips/cpu/start.S 240 241and so on. From there, three functions are called; the purpose and 242limitations of each of these functions are described below. 243 244lowlevel_init(): 245 - purpose: essential init to permit execution to reach board_init_f() 246 - no global_data or BSS 247 - there is no stack (ARMv7 may have one but it will soon be removed) 248 - must not set up SDRAM or use console 249 - must only do the bare minimum to allow execution to continue to 250 board_init_f() 251 - this is almost never needed 252 - return normally from this function 253 254board_init_f(): 255 - purpose: set up the machine ready for running board_init_r(): 256 i.e. SDRAM and serial UART 257 - global_data is available 258 - stack is in SRAM 259 - BSS is not available, so you cannot use global/static variables, 260 only stack variables and global_data 261 262 Non-SPL-specific notes: 263 - dram_init() is called to set up DRAM. If already done in SPL this 264 can do nothing 265 266 SPL-specific notes: 267 - you can override the entire board_init_f() function with your own 268 version as needed. 269 - preloader_console_init() can be called here in extremis 270 - should set up SDRAM, and anything needed to make the UART work 271 - these is no need to clear BSS, it will be done by crt0.S 272 - must return normally from this function (don't call board_init_r() 273 directly) 274 275Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 276this point the stack and global_data are relocated to below 277CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 278memory. 279 280board_init_r(): 281 - purpose: main execution, common code 282 - global_data is available 283 - SDRAM is available 284 - BSS is available, all static/global variables can be used 285 - execution eventually continues to main_loop() 286 287 Non-SPL-specific notes: 288 - U-Boot is relocated to the top of memory and is now running from 289 there. 290 291 SPL-specific notes: 292 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 293 CONFIG_SPL_STACK_R_ADDR points into SDRAM 294 - preloader_console_init() can be called here - typically this is 295 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a 296 spl_board_init() function containing this call 297 - loads U-Boot or (in falcon mode) Linux 298 299 300 301Configuration Options: 302---------------------- 303 304Configuration depends on the combination of board and CPU type; all 305such information is kept in a configuration file 306"include/configs/<board_name>.h". 307 308Example: For a TQM823L module, all configuration settings are in 309"include/configs/TQM823L.h". 310 311 312Many of the options are named exactly as the corresponding Linux 313kernel configuration options. The intention is to make it easier to 314build a config tool - later. 315 316- ARM Platform Bus Type(CCI): 317 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which 318 provides full cache coherency between two clusters of multi-core 319 CPUs and I/O coherency for devices and I/O masters 320 321 CONFIG_SYS_FSL_HAS_CCI400 322 323 Defined For SoC that has cache coherent interconnect 324 CCN-400 325 326 CONFIG_SYS_FSL_HAS_CCN504 327 328 Defined for SoC that has cache coherent interconnect CCN-504 329 330The following options need to be configured: 331 332- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 333 334- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 335 336- Marvell Family Member 337 CONFIG_SYS_MVFS - define it if you want to enable 338 multiple fs option at one time 339 for marvell soc family 340 341- 85xx CPU Options: 342 CONFIG_SYS_PPC64 343 344 Specifies that the core is a 64-bit PowerPC implementation (implements 345 the "64" category of the Power ISA). This is necessary for ePAPR 346 compliance, among other possible reasons. 347 348 CONFIG_SYS_FSL_TBCLK_DIV 349 350 Defines the core time base clock divider ratio compared to the 351 system clock. On most PQ3 devices this is 8, on newer QorIQ 352 devices it can be 16 or 32. The ratio varies from SoC to Soc. 353 354 CONFIG_SYS_FSL_PCIE_COMPAT 355 356 Defines the string to utilize when trying to match PCIe device 357 tree nodes for the given platform. 358 359 CONFIG_SYS_FSL_ERRATUM_A004510 360 361 Enables a workaround for erratum A004510. If set, 362 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 363 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 364 365 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 366 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 367 368 Defines one or two SoC revisions (low 8 bits of SVR) 369 for which the A004510 workaround should be applied. 370 371 The rest of SVR is either not relevant to the decision 372 of whether the erratum is present (e.g. p2040 versus 373 p2041) or is implied by the build target, which controls 374 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 375 376 See Freescale App Note 4493 for more information about 377 this erratum. 378 379 CONFIG_A003399_NOR_WORKAROUND 380 Enables a workaround for IFC erratum A003399. It is only 381 required during NOR boot. 382 383 CONFIG_A008044_WORKAROUND 384 Enables a workaround for T1040/T1042 erratum A008044. It is only 385 required during NAND boot and valid for Rev 1.0 SoC revision 386 387 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 388 389 This is the value to write into CCSR offset 0x18600 390 according to the A004510 workaround. 391 392 CONFIG_SYS_FSL_DSP_DDR_ADDR 393 This value denotes start offset of DDR memory which is 394 connected exclusively to the DSP cores. 395 396 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 397 This value denotes start offset of M2 memory 398 which is directly connected to the DSP core. 399 400 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 401 This value denotes start offset of M3 memory which is directly 402 connected to the DSP core. 403 404 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 405 This value denotes start offset of DSP CCSR space. 406 407 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 408 Single Source Clock is clocking mode present in some of FSL SoC's. 409 In this mode, a single differential clock is used to supply 410 clocks to the sysclock, ddrclock and usbclock. 411 412 CONFIG_SYS_CPC_REINIT_F 413 This CONFIG is defined when the CPC is configured as SRAM at the 414 time of U-Boot entry and is required to be re-initialized. 415 416 CONFIG_DEEP_SLEEP 417 Indicates this SoC supports deep sleep feature. If deep sleep is 418 supported, core will start to execute uboot when wakes up. 419 420- Generic CPU options: 421 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 422 423 Defines the endianess of the CPU. Implementation of those 424 values is arch specific. 425 426 CONFIG_SYS_FSL_DDR 427 Freescale DDR driver in use. This type of DDR controller is 428 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 429 SoCs. 430 431 CONFIG_SYS_FSL_DDR_ADDR 432 Freescale DDR memory-mapped register base. 433 434 CONFIG_SYS_FSL_DDR_EMU 435 Specify emulator support for DDR. Some DDR features such as 436 deskew training are not available. 437 438 CONFIG_SYS_FSL_DDRC_GEN1 439 Freescale DDR1 controller. 440 441 CONFIG_SYS_FSL_DDRC_GEN2 442 Freescale DDR2 controller. 443 444 CONFIG_SYS_FSL_DDRC_GEN3 445 Freescale DDR3 controller. 446 447 CONFIG_SYS_FSL_DDRC_GEN4 448 Freescale DDR4 controller. 449 450 CONFIG_SYS_FSL_DDRC_ARM_GEN3 451 Freescale DDR3 controller for ARM-based SoCs. 452 453 CONFIG_SYS_FSL_DDR1 454 Board config to use DDR1. It can be enabled for SoCs with 455 Freescale DDR1 or DDR2 controllers, depending on the board 456 implemetation. 457 458 CONFIG_SYS_FSL_DDR2 459 Board config to use DDR2. It can be enabled for SoCs with 460 Freescale DDR2 or DDR3 controllers, depending on the board 461 implementation. 462 463 CONFIG_SYS_FSL_DDR3 464 Board config to use DDR3. It can be enabled for SoCs with 465 Freescale DDR3 or DDR3L controllers. 466 467 CONFIG_SYS_FSL_DDR3L 468 Board config to use DDR3L. It can be enabled for SoCs with 469 DDR3L controllers. 470 471 CONFIG_SYS_FSL_DDR4 472 Board config to use DDR4. It can be enabled for SoCs with 473 DDR4 controllers. 474 475 CONFIG_SYS_FSL_IFC_BE 476 Defines the IFC controller register space as Big Endian 477 478 CONFIG_SYS_FSL_IFC_LE 479 Defines the IFC controller register space as Little Endian 480 481 CONFIG_SYS_FSL_IFC_CLK_DIV 482 Defines divider of platform clock(clock input to IFC controller). 483 484 CONFIG_SYS_FSL_LBC_CLK_DIV 485 Defines divider of platform clock(clock input to eLBC controller). 486 487 CONFIG_SYS_FSL_PBL_PBI 488 It enables addition of RCW (Power on reset configuration) in built image. 489 Please refer doc/README.pblimage for more details 490 491 CONFIG_SYS_FSL_PBL_RCW 492 It adds PBI(pre-boot instructions) commands in u-boot build image. 493 PBI commands can be used to configure SoC before it starts the execution. 494 Please refer doc/README.pblimage for more details 495 496 CONFIG_SPL_FSL_PBL 497 It adds a target to create boot binary having SPL binary in PBI format 498 concatenated with u-boot binary. 499 500 CONFIG_SYS_FSL_DDR_BE 501 Defines the DDR controller register space as Big Endian 502 503 CONFIG_SYS_FSL_DDR_LE 504 Defines the DDR controller register space as Little Endian 505 506 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 507 Physical address from the view of DDR controllers. It is the 508 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 509 it could be different for ARM SoCs. 510 511 CONFIG_SYS_FSL_DDR_INTLV_256B 512 DDR controller interleaving on 256-byte. This is a special 513 interleaving mode, handled by Dickens for Freescale layerscape 514 SoCs with ARM core. 515 516 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 517 Number of controllers used as main memory. 518 519 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 520 Number of controllers used for other than main memory. 521 522 CONFIG_SYS_FSL_HAS_DP_DDR 523 Defines the SoC has DP-DDR used for DPAA. 524 525 CONFIG_SYS_FSL_SEC_BE 526 Defines the SEC controller register space as Big Endian 527 528 CONFIG_SYS_FSL_SEC_LE 529 Defines the SEC controller register space as Little Endian 530 531- MIPS CPU options: 532 CONFIG_SYS_INIT_SP_OFFSET 533 534 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 535 pointer. This is needed for the temporary stack before 536 relocation. 537 538 CONFIG_SYS_MIPS_CACHE_MODE 539 540 Cache operation mode for the MIPS CPU. 541 See also arch/mips/include/asm/mipsregs.h. 542 Possible values are: 543 CONF_CM_CACHABLE_NO_WA 544 CONF_CM_CACHABLE_WA 545 CONF_CM_UNCACHED 546 CONF_CM_CACHABLE_NONCOHERENT 547 CONF_CM_CACHABLE_CE 548 CONF_CM_CACHABLE_COW 549 CONF_CM_CACHABLE_CUW 550 CONF_CM_CACHABLE_ACCELERATED 551 552 CONFIG_SYS_XWAY_EBU_BOOTCFG 553 554 Special option for Lantiq XWAY SoCs for booting from NOR flash. 555 See also arch/mips/cpu/mips32/start.S. 556 557 CONFIG_XWAY_SWAP_BYTES 558 559 Enable compilation of tools/xway-swap-bytes needed for Lantiq 560 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 561 be swapped if a flash programmer is used. 562 563- ARM options: 564 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 565 566 Select high exception vectors of the ARM core, e.g., do not 567 clear the V bit of the c1 register of CP15. 568 569 COUNTER_FREQUENCY 570 Generic timer clock source frequency. 571 572 COUNTER_FREQUENCY_REAL 573 Generic timer clock source frequency if the real clock is 574 different from COUNTER_FREQUENCY, and can only be determined 575 at run time. 576 577- Tegra SoC options: 578 CONFIG_TEGRA_SUPPORT_NON_SECURE 579 580 Support executing U-Boot in non-secure (NS) mode. Certain 581 impossible actions will be skipped if the CPU is in NS mode, 582 such as ARM architectural timer initialization. 583 584- Linux Kernel Interface: 585 CONFIG_CLOCKS_IN_MHZ 586 587 U-Boot stores all clock information in Hz 588 internally. For binary compatibility with older Linux 589 kernels (which expect the clocks passed in the 590 bd_info data to be in MHz) the environment variable 591 "clocks_in_mhz" can be defined so that U-Boot 592 converts clock data to MHZ before passing it to the 593 Linux kernel. 594 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 595 "clocks_in_mhz=1" is automatically included in the 596 default environment. 597 598 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 599 600 When transferring memsize parameter to Linux, some versions 601 expect it to be in bytes, others in MB. 602 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 603 604 CONFIG_OF_LIBFDT 605 606 New kernel versions are expecting firmware settings to be 607 passed using flattened device trees (based on open firmware 608 concepts). 609 610 CONFIG_OF_LIBFDT 611 * New libfdt-based support 612 * Adds the "fdt" command 613 * The bootm command automatically updates the fdt 614 615 OF_TBCLK - The timebase frequency. 616 OF_STDOUT_PATH - The path to the console device 617 618 boards with QUICC Engines require OF_QE to set UCC MAC 619 addresses 620 621 CONFIG_OF_BOARD_SETUP 622 623 Board code has addition modification that it wants to make 624 to the flat device tree before handing it off to the kernel 625 626 CONFIG_OF_SYSTEM_SETUP 627 628 Other code has addition modification that it wants to make 629 to the flat device tree before handing it off to the kernel. 630 This causes ft_system_setup() to be called before booting 631 the kernel. 632 633 CONFIG_OF_IDE_FIXUP 634 635 U-Boot can detect if an IDE device is present or not. 636 If not, and this new config option is activated, U-Boot 637 removes the ATA node from the DTS before booting Linux, 638 so the Linux IDE driver does not probe the device and 639 crash. This is needed for buggy hardware (uc101) where 640 no pull down resistor is connected to the signal IDE5V_DD7. 641 642 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 643 644 This setting is mandatory for all boards that have only one 645 machine type and must be used to specify the machine type 646 number as it appears in the ARM machine registry 647 (see http://www.arm.linux.org.uk/developer/machines/). 648 Only boards that have multiple machine types supported 649 in a single configuration file and the machine type is 650 runtime discoverable, do not have to use this setting. 651 652- vxWorks boot parameters: 653 654 bootvx constructs a valid bootline using the following 655 environments variables: bootdev, bootfile, ipaddr, netmask, 656 serverip, gatewayip, hostname, othbootargs. 657 It loads the vxWorks image pointed bootfile. 658 659 Note: If a "bootargs" environment is defined, it will overwride 660 the defaults discussed just above. 661 662- Cache Configuration: 663 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 664 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 665 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 666 667- Cache Configuration for ARM: 668 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 669 controller 670 CONFIG_SYS_PL310_BASE - Physical base address of PL310 671 controller register space 672 673- Serial Ports: 674 CONFIG_PL010_SERIAL 675 676 Define this if you want support for Amba PrimeCell PL010 UARTs. 677 678 CONFIG_PL011_SERIAL 679 680 Define this if you want support for Amba PrimeCell PL011 UARTs. 681 682 CONFIG_PL011_CLOCK 683 684 If you have Amba PrimeCell PL011 UARTs, set this variable to 685 the clock speed of the UARTs. 686 687 CONFIG_PL01x_PORTS 688 689 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 690 define this to a list of base addresses for each (supported) 691 port. See e.g. include/configs/versatile.h 692 693 CONFIG_SERIAL_HW_FLOW_CONTROL 694 695 Define this variable to enable hw flow control in serial driver. 696 Current user of this option is drivers/serial/nsl16550.c driver 697 698- Console Baudrate: 699 CONFIG_BAUDRATE - in bps 700 Select one of the baudrates listed in 701 CONFIG_SYS_BAUDRATE_TABLE, see below. 702 703- Autoboot Command: 704 CONFIG_BOOTCOMMAND 705 Only needed when CONFIG_BOOTDELAY is enabled; 706 define a command string that is automatically executed 707 when no character is read on the console interface 708 within "Boot Delay" after reset. 709 710 CONFIG_RAMBOOT and CONFIG_NFSBOOT 711 The value of these goes into the environment as 712 "ramboot" and "nfsboot" respectively, and can be used 713 as a convenience, when switching between booting from 714 RAM and NFS. 715 716- Bootcount: 717 CONFIG_BOOTCOUNT_LIMIT 718 Implements a mechanism for detecting a repeating reboot 719 cycle, see: 720 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 721 722 CONFIG_BOOTCOUNT_ENV 723 If no softreset save registers are found on the hardware 724 "bootcount" is stored in the environment. To prevent a 725 saveenv on all reboots, the environment variable 726 "upgrade_available" is used. If "upgrade_available" is 727 0, "bootcount" is always 0, if "upgrade_available" is 728 1 "bootcount" is incremented in the environment. 729 So the Userspace Applikation must set the "upgrade_available" 730 and "bootcount" variable to 0, if a boot was successfully. 731 732- Pre-Boot Commands: 733 CONFIG_PREBOOT 734 735 When this option is #defined, the existence of the 736 environment variable "preboot" will be checked 737 immediately before starting the CONFIG_BOOTDELAY 738 countdown and/or running the auto-boot command resp. 739 entering interactive mode. 740 741 This feature is especially useful when "preboot" is 742 automatically generated or modified. For an example 743 see the LWMON board specific code: here "preboot" is 744 modified when the user holds down a certain 745 combination of keys on the (special) keyboard when 746 booting the systems 747 748- Serial Download Echo Mode: 749 CONFIG_LOADS_ECHO 750 If defined to 1, all characters received during a 751 serial download (using the "loads" command) are 752 echoed back. This might be needed by some terminal 753 emulations (like "cu"), but may as well just take 754 time on others. This setting #define's the initial 755 value of the "loads_echo" environment variable. 756 757- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 758 CONFIG_KGDB_BAUDRATE 759 Select one of the baudrates listed in 760 CONFIG_SYS_BAUDRATE_TABLE, see below. 761 762- Removal of commands 763 If no commands are needed to boot, you can disable 764 CONFIG_CMDLINE to remove them. In this case, the command line 765 will not be available, and when U-Boot wants to execute the 766 boot command (on start-up) it will call board_run_command() 767 instead. This can reduce image size significantly for very 768 simple boot procedures. 769 770- Regular expression support: 771 CONFIG_REGEX 772 If this variable is defined, U-Boot is linked against 773 the SLRE (Super Light Regular Expression) library, 774 which adds regex support to some commands, as for 775 example "env grep" and "setexpr". 776 777- Device tree: 778 CONFIG_OF_CONTROL 779 If this variable is defined, U-Boot will use a device tree 780 to configure its devices, instead of relying on statically 781 compiled #defines in the board file. This option is 782 experimental and only available on a few boards. The device 783 tree is available in the global data as gd->fdt_blob. 784 785 U-Boot needs to get its device tree from somewhere. This can 786 be done using one of the three options below: 787 788 CONFIG_OF_EMBED 789 If this variable is defined, U-Boot will embed a device tree 790 binary in its image. This device tree file should be in the 791 board directory and called <soc>-<board>.dts. The binary file 792 is then picked up in board_init_f() and made available through 793 the global data structure as gd->fdt_blob. 794 795 CONFIG_OF_SEPARATE 796 If this variable is defined, U-Boot will build a device tree 797 binary. It will be called u-boot.dtb. Architecture-specific 798 code will locate it at run-time. Generally this works by: 799 800 cat u-boot.bin u-boot.dtb >image.bin 801 802 and in fact, U-Boot does this for you, creating a file called 803 u-boot-dtb.bin which is useful in the common case. You can 804 still use the individual files if you need something more 805 exotic. 806 807 CONFIG_OF_BOARD 808 If this variable is defined, U-Boot will use the device tree 809 provided by the board at runtime instead of embedding one with 810 the image. Only boards defining board_fdt_blob_setup() support 811 this option (see include/fdtdec.h file). 812 813- Watchdog: 814 CONFIG_WATCHDOG 815 If this variable is defined, it enables watchdog 816 support for the SoC. There must be support in the SoC 817 specific code for a watchdog. For the 8xx 818 CPUs, the SIU Watchdog feature is enabled in the SYPCR 819 register. When supported for a specific SoC is 820 available, then no further board specific code should 821 be needed to use it. 822 823 CONFIG_HW_WATCHDOG 824 When using a watchdog circuitry external to the used 825 SoC, then define this variable and provide board 826 specific code for the "hw_watchdog_reset" function. 827 828 CONFIG_AT91_HW_WDT_TIMEOUT 829 specify the timeout in seconds. default 2 seconds. 830 831- U-Boot Version: 832 CONFIG_VERSION_VARIABLE 833 If this variable is defined, an environment variable 834 named "ver" is created by U-Boot showing the U-Boot 835 version as printed by the "version" command. 836 Any change to this variable will be reverted at the 837 next reset. 838 839- Real-Time Clock: 840 841 When CONFIG_CMD_DATE is selected, the type of the RTC 842 has to be selected, too. Define exactly one of the 843 following options: 844 845 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 846 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 847 CONFIG_RTC_MC146818 - use MC146818 RTC 848 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 849 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 850 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 851 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 852 CONFIG_RTC_DS164x - use Dallas DS164x RTC 853 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 854 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 855 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 856 CONFIG_SYS_RV3029_TCR - enable trickle charger on 857 RV3029 RTC. 858 859 Note that if the RTC uses I2C, then the I2C interface 860 must also be configured. See I2C Support, below. 861 862- GPIO Support: 863 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 864 865 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 866 chip-ngpio pairs that tell the PCA953X driver the number of 867 pins supported by a particular chip. 868 869 Note that if the GPIO device uses I2C, then the I2C interface 870 must also be configured. See I2C Support, below. 871 872- I/O tracing: 873 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 874 accesses and can checksum them or write a list of them out 875 to memory. See the 'iotrace' command for details. This is 876 useful for testing device drivers since it can confirm that 877 the driver behaves the same way before and after a code 878 change. Currently this is supported on sandbox and arm. To 879 add support for your architecture, add '#include <iotrace.h>' 880 to the bottom of arch/<arch>/include/asm/io.h and test. 881 882 Example output from the 'iotrace stats' command is below. 883 Note that if the trace buffer is exhausted, the checksum will 884 still continue to operate. 885 886 iotrace is enabled 887 Start: 10000000 (buffer start address) 888 Size: 00010000 (buffer size) 889 Offset: 00000120 (current buffer offset) 890 Output: 10000120 (start + offset) 891 Count: 00000018 (number of trace records) 892 CRC32: 9526fb66 (CRC32 of all trace records) 893 894- Timestamp Support: 895 896 When CONFIG_TIMESTAMP is selected, the timestamp 897 (date and time) of an image is printed by image 898 commands like bootm or iminfo. This option is 899 automatically enabled when you select CONFIG_CMD_DATE . 900 901- Partition Labels (disklabels) Supported: 902 Zero or more of the following: 903 CONFIG_MAC_PARTITION Apple's MacOS partition table. 904 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 905 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 906 bootloader. Note 2TB partition limit; see 907 disk/part_efi.c 908 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 909 910 If IDE or SCSI support is enabled (CONFIG_IDE or 911 CONFIG_SCSI) you must configure support for at 912 least one non-MTD partition type as well. 913 914- IDE Reset method: 915 CONFIG_IDE_RESET_ROUTINE - this is defined in several 916 board configurations files but used nowhere! 917 918 CONFIG_IDE_RESET - is this is defined, IDE Reset will 919 be performed by calling the function 920 ide_set_reset(int reset) 921 which has to be defined in a board specific file 922 923- ATAPI Support: 924 CONFIG_ATAPI 925 926 Set this to enable ATAPI support. 927 928- LBA48 Support 929 CONFIG_LBA48 930 931 Set this to enable support for disks larger than 137GB 932 Also look at CONFIG_SYS_64BIT_LBA. 933 Whithout these , LBA48 support uses 32bit variables and will 'only' 934 support disks up to 2.1TB. 935 936 CONFIG_SYS_64BIT_LBA: 937 When enabled, makes the IDE subsystem use 64bit sector addresses. 938 Default is 32bit. 939 940- SCSI Support: 941 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 942 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 943 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 944 maximum numbers of LUNs, SCSI ID's and target 945 devices. 946 947 The environment variable 'scsidevs' is set to the number of 948 SCSI devices found during the last scan. 949 950- NETWORK Support (PCI): 951 CONFIG_E1000 952 Support for Intel 8254x/8257x gigabit chips. 953 954 CONFIG_E1000_SPI 955 Utility code for direct access to the SPI bus on Intel 8257x. 956 This does not do anything useful unless you set at least one 957 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 958 959 CONFIG_E1000_SPI_GENERIC 960 Allow generic access to the SPI bus on the Intel 8257x, for 961 example with the "sspi" command. 962 963 CONFIG_EEPRO100 964 Support for Intel 82557/82559/82559ER chips. 965 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 966 write routine for first time initialisation. 967 968 CONFIG_TULIP 969 Support for Digital 2114x chips. 970 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 971 modem chip initialisation (KS8761/QS6611). 972 973 CONFIG_NATSEMI 974 Support for National dp83815 chips. 975 976 CONFIG_NS8382X 977 Support for National dp8382[01] gigabit chips. 978 979- NETWORK Support (other): 980 981 CONFIG_DRIVER_AT91EMAC 982 Support for AT91RM9200 EMAC. 983 984 CONFIG_RMII 985 Define this to use reduced MII inteface 986 987 CONFIG_DRIVER_AT91EMAC_QUIET 988 If this defined, the driver is quiet. 989 The driver doen't show link status messages. 990 991 CONFIG_CALXEDA_XGMAC 992 Support for the Calxeda XGMAC device 993 994 CONFIG_LAN91C96 995 Support for SMSC's LAN91C96 chips. 996 997 CONFIG_LAN91C96_USE_32_BIT 998 Define this to enable 32 bit addressing 999 1000 CONFIG_SMC91111 1001 Support for SMSC's LAN91C111 chip 1002 1003 CONFIG_SMC91111_BASE 1004 Define this to hold the physical address 1005 of the device (I/O space) 1006 1007 CONFIG_SMC_USE_32_BIT 1008 Define this if data bus is 32 bits 1009 1010 CONFIG_SMC_USE_IOFUNCS 1011 Define this to use i/o functions instead of macros 1012 (some hardware wont work with macros) 1013 1014 CONFIG_DRIVER_TI_EMAC 1015 Support for davinci emac 1016 1017 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1018 Define this if you have more then 3 PHYs. 1019 1020 CONFIG_FTGMAC100 1021 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1022 1023 CONFIG_FTGMAC100_EGIGA 1024 Define this to use GE link update with gigabit PHY. 1025 Define this if FTGMAC100 is connected to gigabit PHY. 1026 If your system has 10/100 PHY only, it might not occur 1027 wrong behavior. Because PHY usually return timeout or 1028 useless data when polling gigabit status and gigabit 1029 control registers. This behavior won't affect the 1030 correctnessof 10/100 link speed update. 1031 1032 CONFIG_SH_ETHER 1033 Support for Renesas on-chip Ethernet controller 1034 1035 CONFIG_SH_ETHER_USE_PORT 1036 Define the number of ports to be used 1037 1038 CONFIG_SH_ETHER_PHY_ADDR 1039 Define the ETH PHY's address 1040 1041 CONFIG_SH_ETHER_CACHE_WRITEBACK 1042 If this option is set, the driver enables cache flush. 1043 1044- PWM Support: 1045 CONFIG_PWM_IMX 1046 Support for PWM module on the imx6. 1047 1048- TPM Support: 1049 CONFIG_TPM 1050 Support TPM devices. 1051 1052 CONFIG_TPM_TIS_INFINEON 1053 Support for Infineon i2c bus TPM devices. Only one device 1054 per system is supported at this time. 1055 1056 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1057 Define the burst count bytes upper limit 1058 1059 CONFIG_TPM_ST33ZP24 1060 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1061 1062 CONFIG_TPM_ST33ZP24_I2C 1063 Support for STMicroelectronics ST33ZP24 I2C devices. 1064 Requires TPM_ST33ZP24 and I2C. 1065 1066 CONFIG_TPM_ST33ZP24_SPI 1067 Support for STMicroelectronics ST33ZP24 SPI devices. 1068 Requires TPM_ST33ZP24 and SPI. 1069 1070 CONFIG_TPM_ATMEL_TWI 1071 Support for Atmel TWI TPM device. Requires I2C support. 1072 1073 CONFIG_TPM_TIS_LPC 1074 Support for generic parallel port TPM devices. Only one device 1075 per system is supported at this time. 1076 1077 CONFIG_TPM_TIS_BASE_ADDRESS 1078 Base address where the generic TPM device is mapped 1079 to. Contemporary x86 systems usually map it at 1080 0xfed40000. 1081 1082 CONFIG_TPM 1083 Define this to enable the TPM support library which provides 1084 functional interfaces to some TPM commands. 1085 Requires support for a TPM device. 1086 1087 CONFIG_TPM_AUTH_SESSIONS 1088 Define this to enable authorized functions in the TPM library. 1089 Requires CONFIG_TPM and CONFIG_SHA1. 1090 1091- USB Support: 1092 At the moment only the UHCI host controller is 1093 supported (PIP405, MIP405); define 1094 CONFIG_USB_UHCI to enable it. 1095 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1096 and define CONFIG_USB_STORAGE to enable the USB 1097 storage devices. 1098 Note: 1099 Supported are USB Keyboards and USB Floppy drives 1100 (TEAC FD-05PUB). 1101 1102 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1103 txfilltuning field in the EHCI controller on reset. 1104 1105 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1106 HW module registers. 1107 1108- USB Device: 1109 Define the below if you wish to use the USB console. 1110 Once firmware is rebuilt from a serial console issue the 1111 command "setenv stdin usbtty; setenv stdout usbtty" and 1112 attach your USB cable. The Unix command "dmesg" should print 1113 it has found a new device. The environment variable usbtty 1114 can be set to gserial or cdc_acm to enable your device to 1115 appear to a USB host as a Linux gserial device or a 1116 Common Device Class Abstract Control Model serial device. 1117 If you select usbtty = gserial you should be able to enumerate 1118 a Linux host by 1119 # modprobe usbserial vendor=0xVendorID product=0xProductID 1120 else if using cdc_acm, simply setting the environment 1121 variable usbtty to be cdc_acm should suffice. The following 1122 might be defined in YourBoardName.h 1123 1124 CONFIG_USB_DEVICE 1125 Define this to build a UDC device 1126 1127 CONFIG_USB_TTY 1128 Define this to have a tty type of device available to 1129 talk to the UDC device 1130 1131 CONFIG_USBD_HS 1132 Define this to enable the high speed support for usb 1133 device and usbtty. If this feature is enabled, a routine 1134 int is_usbd_high_speed(void) 1135 also needs to be defined by the driver to dynamically poll 1136 whether the enumeration has succeded at high speed or full 1137 speed. 1138 1139 CONFIG_SYS_CONSOLE_IS_IN_ENV 1140 Define this if you want stdin, stdout &/or stderr to 1141 be set to usbtty. 1142 1143 If you have a USB-IF assigned VendorID then you may wish to 1144 define your own vendor specific values either in BoardName.h 1145 or directly in usbd_vendor_info.h. If you don't define 1146 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1147 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1148 should pretend to be a Linux device to it's target host. 1149 1150 CONFIG_USBD_MANUFACTURER 1151 Define this string as the name of your company for 1152 - CONFIG_USBD_MANUFACTURER "my company" 1153 1154 CONFIG_USBD_PRODUCT_NAME 1155 Define this string as the name of your product 1156 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1157 1158 CONFIG_USBD_VENDORID 1159 Define this as your assigned Vendor ID from the USB 1160 Implementors Forum. This *must* be a genuine Vendor ID 1161 to avoid polluting the USB namespace. 1162 - CONFIG_USBD_VENDORID 0xFFFF 1163 1164 CONFIG_USBD_PRODUCTID 1165 Define this as the unique Product ID 1166 for your device 1167 - CONFIG_USBD_PRODUCTID 0xFFFF 1168 1169- ULPI Layer Support: 1170 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1171 the generic ULPI layer. The generic layer accesses the ULPI PHY 1172 via the platform viewport, so you need both the genric layer and 1173 the viewport enabled. Currently only Chipidea/ARC based 1174 viewport is supported. 1175 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1176 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1177 If your ULPI phy needs a different reference clock than the 1178 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1179 the appropriate value in Hz. 1180 1181- MMC Support: 1182 The MMC controller on the Intel PXA is supported. To 1183 enable this define CONFIG_MMC. The MMC can be 1184 accessed from the boot prompt by mapping the device 1185 to physical memory similar to flash. Command line is 1186 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1187 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1188 1189 CONFIG_SH_MMCIF 1190 Support for Renesas on-chip MMCIF controller 1191 1192 CONFIG_SH_MMCIF_ADDR 1193 Define the base address of MMCIF registers 1194 1195 CONFIG_SH_MMCIF_CLK 1196 Define the clock frequency for MMCIF 1197 1198 CONFIG_SUPPORT_EMMC_BOOT 1199 Enable some additional features of the eMMC boot partitions. 1200 1201 CONFIG_SUPPORT_EMMC_RPMB 1202 Enable the commands for reading, writing and programming the 1203 key for the Replay Protection Memory Block partition in eMMC. 1204 1205- USB Device Firmware Update (DFU) class support: 1206 CONFIG_USB_FUNCTION_DFU 1207 This enables the USB portion of the DFU USB class 1208 1209 CONFIG_DFU_MMC 1210 This enables support for exposing (e)MMC devices via DFU. 1211 1212 CONFIG_DFU_NAND 1213 This enables support for exposing NAND devices via DFU. 1214 1215 CONFIG_DFU_RAM 1216 This enables support for exposing RAM via DFU. 1217 Note: DFU spec refer to non-volatile memory usage, but 1218 allow usages beyond the scope of spec - here RAM usage, 1219 one that would help mostly the developer. 1220 1221 CONFIG_SYS_DFU_DATA_BUF_SIZE 1222 Dfu transfer uses a buffer before writing data to the 1223 raw storage device. Make the size (in bytes) of this buffer 1224 configurable. The size of this buffer is also configurable 1225 through the "dfu_bufsiz" environment variable. 1226 1227 CONFIG_SYS_DFU_MAX_FILE_SIZE 1228 When updating files rather than the raw storage device, 1229 we use a static buffer to copy the file into and then write 1230 the buffer once we've been given the whole file. Define 1231 this to the maximum filesize (in bytes) for the buffer. 1232 Default is 4 MiB if undefined. 1233 1234 DFU_DEFAULT_POLL_TIMEOUT 1235 Poll timeout [ms], is the timeout a device can send to the 1236 host. The host must wait for this timeout before sending 1237 a subsequent DFU_GET_STATUS request to the device. 1238 1239 DFU_MANIFEST_POLL_TIMEOUT 1240 Poll timeout [ms], which the device sends to the host when 1241 entering dfuMANIFEST state. Host waits this timeout, before 1242 sending again an USB request to the device. 1243 1244- Journaling Flash filesystem support: 1245 CONFIG_JFFS2_NAND 1246 Define these for a default partition on a NAND device 1247 1248 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1249 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1250 Define these for a default partition on a NOR device 1251 1252- Keyboard Support: 1253 See Kconfig help for available keyboard drivers. 1254 1255 CONFIG_KEYBOARD 1256 1257 Define this to enable a custom keyboard support. 1258 This simply calls drv_keyboard_init() which must be 1259 defined in your board-specific files. This option is deprecated 1260 and is only used by novena. For new boards, use driver model 1261 instead. 1262 1263- Video support: 1264 CONFIG_FSL_DIU_FB 1265 Enable the Freescale DIU video driver. Reference boards for 1266 SOCs that have a DIU should define this macro to enable DIU 1267 support, and should also define these other macros: 1268 1269 CONFIG_SYS_DIU_ADDR 1270 CONFIG_VIDEO 1271 CONFIG_CFB_CONSOLE 1272 CONFIG_VIDEO_SW_CURSOR 1273 CONFIG_VGA_AS_SINGLE_DEVICE 1274 CONFIG_VIDEO_LOGO 1275 CONFIG_VIDEO_BMP_LOGO 1276 1277 The DIU driver will look for the 'video-mode' environment 1278 variable, and if defined, enable the DIU as a console during 1279 boot. See the documentation file doc/README.video for a 1280 description of this variable. 1281 1282- LCD Support: CONFIG_LCD 1283 1284 Define this to enable LCD support (for output to LCD 1285 display); also select one of the supported displays 1286 by defining one of these: 1287 1288 CONFIG_ATMEL_LCD: 1289 1290 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1291 1292 CONFIG_NEC_NL6448AC33: 1293 1294 NEC NL6448AC33-18. Active, color, single scan. 1295 1296 CONFIG_NEC_NL6448BC20 1297 1298 NEC NL6448BC20-08. 6.5", 640x480. 1299 Active, color, single scan. 1300 1301 CONFIG_NEC_NL6448BC33_54 1302 1303 NEC NL6448BC33-54. 10.4", 640x480. 1304 Active, color, single scan. 1305 1306 CONFIG_SHARP_16x9 1307 1308 Sharp 320x240. Active, color, single scan. 1309 It isn't 16x9, and I am not sure what it is. 1310 1311 CONFIG_SHARP_LQ64D341 1312 1313 Sharp LQ64D341 display, 640x480. 1314 Active, color, single scan. 1315 1316 CONFIG_HLD1045 1317 1318 HLD1045 display, 640x480. 1319 Active, color, single scan. 1320 1321 CONFIG_OPTREX_BW 1322 1323 Optrex CBL50840-2 NF-FW 99 22 M5 1324 or 1325 Hitachi LMG6912RPFC-00T 1326 or 1327 Hitachi SP14Q002 1328 1329 320x240. Black & white. 1330 1331 CONFIG_LCD_ALIGNMENT 1332 1333 Normally the LCD is page-aligned (typically 4KB). If this is 1334 defined then the LCD will be aligned to this value instead. 1335 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1336 here, since it is cheaper to change data cache settings on 1337 a per-section basis. 1338 1339 1340 CONFIG_LCD_ROTATION 1341 1342 Sometimes, for example if the display is mounted in portrait 1343 mode or even if it's mounted landscape but rotated by 180degree, 1344 we need to rotate our content of the display relative to the 1345 framebuffer, so that user can read the messages which are 1346 printed out. 1347 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1348 initialized with a given rotation from "vl_rot" out of 1349 "vidinfo_t" which is provided by the board specific code. 1350 The value for vl_rot is coded as following (matching to 1351 fbcon=rotate:<n> linux-kernel commandline): 1352 0 = no rotation respectively 0 degree 1353 1 = 90 degree rotation 1354 2 = 180 degree rotation 1355 3 = 270 degree rotation 1356 1357 If CONFIG_LCD_ROTATION is not defined, the console will be 1358 initialized with 0degree rotation. 1359 1360 CONFIG_LCD_BMP_RLE8 1361 1362 Support drawing of RLE8-compressed bitmaps on the LCD. 1363 1364 CONFIG_I2C_EDID 1365 1366 Enables an 'i2c edid' command which can read EDID 1367 information over I2C from an attached LCD display. 1368 1369- Splash Screen Support: CONFIG_SPLASH_SCREEN 1370 1371 If this option is set, the environment is checked for 1372 a variable "splashimage". If found, the usual display 1373 of logo, copyright and system information on the LCD 1374 is suppressed and the BMP image at the address 1375 specified in "splashimage" is loaded instead. The 1376 console is redirected to the "nulldev", too. This 1377 allows for a "silent" boot where a splash screen is 1378 loaded very quickly after power-on. 1379 1380 CONFIG_SPLASHIMAGE_GUARD 1381 1382 If this option is set, then U-Boot will prevent the environment 1383 variable "splashimage" from being set to a problematic address 1384 (see doc/README.displaying-bmps). 1385 This option is useful for targets where, due to alignment 1386 restrictions, an improperly aligned BMP image will cause a data 1387 abort. If you think you will not have problems with unaligned 1388 accesses (for example because your toolchain prevents them) 1389 there is no need to set this option. 1390 1391 CONFIG_SPLASH_SCREEN_ALIGN 1392 1393 If this option is set the splash image can be freely positioned 1394 on the screen. Environment variable "splashpos" specifies the 1395 position as "x,y". If a positive number is given it is used as 1396 number of pixel from left/top. If a negative number is given it 1397 is used as number of pixel from right/bottom. You can also 1398 specify 'm' for centering the image. 1399 1400 Example: 1401 setenv splashpos m,m 1402 => image at center of screen 1403 1404 setenv splashpos 30,20 1405 => image at x = 30 and y = 20 1406 1407 setenv splashpos -10,m 1408 => vertically centered image 1409 at x = dspWidth - bmpWidth - 9 1410 1411- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1412 1413 If this option is set, additionally to standard BMP 1414 images, gzipped BMP images can be displayed via the 1415 splashscreen support or the bmp command. 1416 1417- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1418 1419 If this option is set, 8-bit RLE compressed BMP images 1420 can be displayed via the splashscreen support or the 1421 bmp command. 1422 1423- Compression support: 1424 CONFIG_GZIP 1425 1426 Enabled by default to support gzip compressed images. 1427 1428 CONFIG_BZIP2 1429 1430 If this option is set, support for bzip2 compressed 1431 images is included. If not, only uncompressed and gzip 1432 compressed images are supported. 1433 1434 NOTE: the bzip2 algorithm requires a lot of RAM, so 1435 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1436 be at least 4MB. 1437 1438- MII/PHY support: 1439 CONFIG_PHY_ADDR 1440 1441 The address of PHY on MII bus. 1442 1443 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1444 1445 The clock frequency of the MII bus 1446 1447 CONFIG_PHY_RESET_DELAY 1448 1449 Some PHY like Intel LXT971A need extra delay after 1450 reset before any MII register access is possible. 1451 For such PHY, set this option to the usec delay 1452 required. (minimum 300usec for LXT971A) 1453 1454 CONFIG_PHY_CMD_DELAY (ppc4xx) 1455 1456 Some PHY like Intel LXT971A need extra delay after 1457 command issued before MII status register can be read 1458 1459- IP address: 1460 CONFIG_IPADDR 1461 1462 Define a default value for the IP address to use for 1463 the default Ethernet interface, in case this is not 1464 determined through e.g. bootp. 1465 (Environment variable "ipaddr") 1466 1467- Server IP address: 1468 CONFIG_SERVERIP 1469 1470 Defines a default value for the IP address of a TFTP 1471 server to contact when using the "tftboot" command. 1472 (Environment variable "serverip") 1473 1474 CONFIG_KEEP_SERVERADDR 1475 1476 Keeps the server's MAC address, in the env 'serveraddr' 1477 for passing to bootargs (like Linux's netconsole option) 1478 1479- Gateway IP address: 1480 CONFIG_GATEWAYIP 1481 1482 Defines a default value for the IP address of the 1483 default router where packets to other networks are 1484 sent to. 1485 (Environment variable "gatewayip") 1486 1487- Subnet mask: 1488 CONFIG_NETMASK 1489 1490 Defines a default value for the subnet mask (or 1491 routing prefix) which is used to determine if an IP 1492 address belongs to the local subnet or needs to be 1493 forwarded through a router. 1494 (Environment variable "netmask") 1495 1496- Multicast TFTP Mode: 1497 CONFIG_MCAST_TFTP 1498 1499 Defines whether you want to support multicast TFTP as per 1500 rfc-2090; for example to work with atftp. Lets lots of targets 1501 tftp down the same boot image concurrently. Note: the Ethernet 1502 driver in use must provide a function: mcast() to join/leave a 1503 multicast group. 1504 1505- BOOTP Recovery Mode: 1506 CONFIG_BOOTP_RANDOM_DELAY 1507 1508 If you have many targets in a network that try to 1509 boot using BOOTP, you may want to avoid that all 1510 systems send out BOOTP requests at precisely the same 1511 moment (which would happen for instance at recovery 1512 from a power failure, when all systems will try to 1513 boot, thus flooding the BOOTP server. Defining 1514 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1515 inserted before sending out BOOTP requests. The 1516 following delays are inserted then: 1517 1518 1st BOOTP request: delay 0 ... 1 sec 1519 2nd BOOTP request: delay 0 ... 2 sec 1520 3rd BOOTP request: delay 0 ... 4 sec 1521 4th and following 1522 BOOTP requests: delay 0 ... 8 sec 1523 1524 CONFIG_BOOTP_ID_CACHE_SIZE 1525 1526 BOOTP packets are uniquely identified using a 32-bit ID. The 1527 server will copy the ID from client requests to responses and 1528 U-Boot will use this to determine if it is the destination of 1529 an incoming response. Some servers will check that addresses 1530 aren't in use before handing them out (usually using an ARP 1531 ping) and therefore take up to a few hundred milliseconds to 1532 respond. Network congestion may also influence the time it 1533 takes for a response to make it back to the client. If that 1534 time is too long, U-Boot will retransmit requests. In order 1535 to allow earlier responses to still be accepted after these 1536 retransmissions, U-Boot's BOOTP client keeps a small cache of 1537 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1538 cache. The default is to keep IDs for up to four outstanding 1539 requests. Increasing this will allow U-Boot to accept offers 1540 from a BOOTP client in networks with unusually high latency. 1541 1542- DHCP Advanced Options: 1543 You can fine tune the DHCP functionality by defining 1544 CONFIG_BOOTP_* symbols: 1545 1546 CONFIG_BOOTP_SUBNETMASK 1547 CONFIG_BOOTP_GATEWAY 1548 CONFIG_BOOTP_HOSTNAME 1549 CONFIG_BOOTP_NISDOMAIN 1550 CONFIG_BOOTP_BOOTPATH 1551 CONFIG_BOOTP_BOOTFILESIZE 1552 CONFIG_BOOTP_DNS 1553 CONFIG_BOOTP_DNS2 1554 CONFIG_BOOTP_SEND_HOSTNAME 1555 CONFIG_BOOTP_NTPSERVER 1556 CONFIG_BOOTP_TIMEOFFSET 1557 CONFIG_BOOTP_VENDOREX 1558 CONFIG_BOOTP_MAY_FAIL 1559 1560 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1561 environment variable, not the BOOTP server. 1562 1563 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1564 after the configured retry count, the call will fail 1565 instead of starting over. This can be used to fail over 1566 to Link-local IP address configuration if the DHCP server 1567 is not available. 1568 1569 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1570 serverip from a DHCP server, it is possible that more 1571 than one DNS serverip is offered to the client. 1572 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1573 serverip will be stored in the additional environment 1574 variable "dnsip2". The first DNS serverip is always 1575 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1576 is defined. 1577 1578 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1579 to do a dynamic update of a DNS server. To do this, they 1580 need the hostname of the DHCP requester. 1581 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1582 of the "hostname" environment variable is passed as 1583 option 12 to the DHCP server. 1584 1585 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1586 1587 A 32bit value in microseconds for a delay between 1588 receiving a "DHCP Offer" and sending the "DHCP Request". 1589 This fixes a problem with certain DHCP servers that don't 1590 respond 100% of the time to a "DHCP request". E.g. On an 1591 AT91RM9200 processor running at 180MHz, this delay needed 1592 to be *at least* 15,000 usec before a Windows Server 2003 1593 DHCP server would reply 100% of the time. I recommend at 1594 least 50,000 usec to be safe. The alternative is to hope 1595 that one of the retries will be successful but note that 1596 the DHCP timeout and retry process takes a longer than 1597 this delay. 1598 1599 - Link-local IP address negotiation: 1600 Negotiate with other link-local clients on the local network 1601 for an address that doesn't require explicit configuration. 1602 This is especially useful if a DHCP server cannot be guaranteed 1603 to exist in all environments that the device must operate. 1604 1605 See doc/README.link-local for more information. 1606 1607 - MAC address from environment variables 1608 1609 FDT_SEQ_MACADDR_FROM_ENV 1610 1611 Fix-up device tree with MAC addresses fetched sequentially from 1612 environment variables. This config work on assumption that 1613 non-usable ethernet node of device-tree are either not present 1614 or their status has been marked as "disabled". 1615 1616 - CDP Options: 1617 CONFIG_CDP_DEVICE_ID 1618 1619 The device id used in CDP trigger frames. 1620 1621 CONFIG_CDP_DEVICE_ID_PREFIX 1622 1623 A two character string which is prefixed to the MAC address 1624 of the device. 1625 1626 CONFIG_CDP_PORT_ID 1627 1628 A printf format string which contains the ascii name of 1629 the port. Normally is set to "eth%d" which sets 1630 eth0 for the first Ethernet, eth1 for the second etc. 1631 1632 CONFIG_CDP_CAPABILITIES 1633 1634 A 32bit integer which indicates the device capabilities; 1635 0x00000010 for a normal host which does not forwards. 1636 1637 CONFIG_CDP_VERSION 1638 1639 An ascii string containing the version of the software. 1640 1641 CONFIG_CDP_PLATFORM 1642 1643 An ascii string containing the name of the platform. 1644 1645 CONFIG_CDP_TRIGGER 1646 1647 A 32bit integer sent on the trigger. 1648 1649 CONFIG_CDP_POWER_CONSUMPTION 1650 1651 A 16bit integer containing the power consumption of the 1652 device in .1 of milliwatts. 1653 1654 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1655 1656 A byte containing the id of the VLAN. 1657 1658- Status LED: CONFIG_LED_STATUS 1659 1660 Several configurations allow to display the current 1661 status using a LED. For instance, the LED will blink 1662 fast while running U-Boot code, stop blinking as 1663 soon as a reply to a BOOTP request was received, and 1664 start blinking slow once the Linux kernel is running 1665 (supported by a status LED driver in the Linux 1666 kernel). Defining CONFIG_LED_STATUS enables this 1667 feature in U-Boot. 1668 1669 Additional options: 1670 1671 CONFIG_LED_STATUS_GPIO 1672 The status LED can be connected to a GPIO pin. 1673 In such cases, the gpio_led driver can be used as a 1674 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 1675 to include the gpio_led driver in the U-Boot binary. 1676 1677 CONFIG_GPIO_LED_INVERTED_TABLE 1678 Some GPIO connected LEDs may have inverted polarity in which 1679 case the GPIO high value corresponds to LED off state and 1680 GPIO low value corresponds to LED on state. 1681 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 1682 with a list of GPIO LEDs that have inverted polarity. 1683 1684- I2C Support: CONFIG_SYS_I2C 1685 1686 This enable the NEW i2c subsystem, and will allow you to use 1687 i2c commands at the u-boot command line (as long as you set 1688 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 1689 based realtime clock chips or other i2c devices. See 1690 common/cmd_i2c.c for a description of the command line 1691 interface. 1692 1693 ported i2c driver to the new framework: 1694 - drivers/i2c/soft_i2c.c: 1695 - activate first bus with CONFIG_SYS_I2C_SOFT define 1696 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 1697 for defining speed and slave address 1698 - activate second bus with I2C_SOFT_DECLARATIONS2 define 1699 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 1700 for defining speed and slave address 1701 - activate third bus with I2C_SOFT_DECLARATIONS3 define 1702 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 1703 for defining speed and slave address 1704 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 1705 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 1706 for defining speed and slave address 1707 1708 - drivers/i2c/fsl_i2c.c: 1709 - activate i2c driver with CONFIG_SYS_I2C_FSL 1710 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 1711 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 1712 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 1713 bus. 1714 - If your board supports a second fsl i2c bus, define 1715 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 1716 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 1717 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 1718 second bus. 1719 1720 - drivers/i2c/tegra_i2c.c: 1721 - activate this driver with CONFIG_SYS_I2C_TEGRA 1722 - This driver adds 4 i2c buses with a fix speed from 1723 100000 and the slave addr 0! 1724 1725 - drivers/i2c/ppc4xx_i2c.c 1726 - activate this driver with CONFIG_SYS_I2C_PPC4XX 1727 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 1728 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 1729 1730 - drivers/i2c/i2c_mxc.c 1731 - activate this driver with CONFIG_SYS_I2C_MXC 1732 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 1733 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 1734 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 1735 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 1736 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 1737 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 1738 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 1739 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 1740 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 1741 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 1742 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 1743 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 1744 If those defines are not set, default value is 100000 1745 for speed, and 0 for slave. 1746 1747 - drivers/i2c/rcar_i2c.c: 1748 - activate this driver with CONFIG_SYS_I2C_RCAR 1749 - This driver adds 4 i2c buses 1750 1751 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 1752 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 1753 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 1754 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 1755 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 1756 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 1757 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 1758 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 1759 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 1760 1761 - drivers/i2c/sh_i2c.c: 1762 - activate this driver with CONFIG_SYS_I2C_SH 1763 - This driver adds from 2 to 5 i2c buses 1764 1765 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 1766 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 1767 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 1768 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 1769 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 1770 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 1771 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 1772 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 1773 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 1774 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 1775 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 1776 1777 - drivers/i2c/omap24xx_i2c.c 1778 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 1779 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 1780 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 1781 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 1782 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 1783 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 1784 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 1785 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 1786 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 1787 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 1788 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 1789 1790 - drivers/i2c/zynq_i2c.c 1791 - activate this driver with CONFIG_SYS_I2C_ZYNQ 1792 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 1793 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 1794 1795 - drivers/i2c/s3c24x0_i2c.c: 1796 - activate this driver with CONFIG_SYS_I2C_S3C24X0 1797 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 1798 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 1799 with a fix speed from 100000 and the slave addr 0! 1800 1801 - drivers/i2c/ihs_i2c.c 1802 - activate this driver with CONFIG_SYS_I2C_IHS 1803 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 1804 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 1805 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 1806 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 1807 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 1808 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 1809 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 1810 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 1811 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 1812 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 1813 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 1814 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 1815 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 1816 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 1817 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 1818 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 1819 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 1820 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 1821 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 1822 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 1823 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 1824 1825 additional defines: 1826 1827 CONFIG_SYS_NUM_I2C_BUSES 1828 Hold the number of i2c buses you want to use. 1829 1830 CONFIG_SYS_I2C_DIRECT_BUS 1831 define this, if you don't use i2c muxes on your hardware. 1832 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 1833 omit this define. 1834 1835 CONFIG_SYS_I2C_MAX_HOPS 1836 define how many muxes are maximal consecutively connected 1837 on one i2c bus. If you not use i2c muxes, omit this 1838 define. 1839 1840 CONFIG_SYS_I2C_BUSES 1841 hold a list of buses you want to use, only used if 1842 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 1843 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 1844 CONFIG_SYS_NUM_I2C_BUSES = 9: 1845 1846 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 1847 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 1848 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 1849 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 1850 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 1851 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 1852 {1, {I2C_NULL_HOP}}, \ 1853 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 1854 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 1855 } 1856 1857 which defines 1858 bus 0 on adapter 0 without a mux 1859 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 1860 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 1861 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 1862 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 1863 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 1864 bus 6 on adapter 1 without a mux 1865 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 1866 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 1867 1868 If you do not have i2c muxes on your board, omit this define. 1869 1870- Legacy I2C Support: 1871 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 1872 then the following macros need to be defined (examples are 1873 from include/configs/lwmon.h): 1874 1875 I2C_INIT 1876 1877 (Optional). Any commands necessary to enable the I2C 1878 controller or configure ports. 1879 1880 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1881 1882 I2C_ACTIVE 1883 1884 The code necessary to make the I2C data line active 1885 (driven). If the data line is open collector, this 1886 define can be null. 1887 1888 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1889 1890 I2C_TRISTATE 1891 1892 The code necessary to make the I2C data line tri-stated 1893 (inactive). If the data line is open collector, this 1894 define can be null. 1895 1896 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1897 1898 I2C_READ 1899 1900 Code that returns true if the I2C data line is high, 1901 false if it is low. 1902 1903 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1904 1905 I2C_SDA(bit) 1906 1907 If <bit> is true, sets the I2C data line high. If it 1908 is false, it clears it (low). 1909 1910 eg: #define I2C_SDA(bit) \ 1911 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1912 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1913 1914 I2C_SCL(bit) 1915 1916 If <bit> is true, sets the I2C clock line high. If it 1917 is false, it clears it (low). 1918 1919 eg: #define I2C_SCL(bit) \ 1920 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1921 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1922 1923 I2C_DELAY 1924 1925 This delay is invoked four times per clock cycle so this 1926 controls the rate of data transfer. The data rate thus 1927 is 1 / (I2C_DELAY * 4). Often defined to be something 1928 like: 1929 1930 #define I2C_DELAY udelay(2) 1931 1932 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1933 1934 If your arch supports the generic GPIO framework (asm/gpio.h), 1935 then you may alternatively define the two GPIOs that are to be 1936 used as SCL / SDA. Any of the previous I2C_xxx macros will 1937 have GPIO-based defaults assigned to them as appropriate. 1938 1939 You should define these to the GPIO value as given directly to 1940 the generic GPIO functions. 1941 1942 CONFIG_SYS_I2C_INIT_BOARD 1943 1944 When a board is reset during an i2c bus transfer 1945 chips might think that the current transfer is still 1946 in progress. On some boards it is possible to access 1947 the i2c SCLK line directly, either by using the 1948 processor pin as a GPIO or by having a second pin 1949 connected to the bus. If this option is defined a 1950 custom i2c_init_board() routine in boards/xxx/board.c 1951 is run early in the boot sequence. 1952 1953 CONFIG_I2C_MULTI_BUS 1954 1955 This option allows the use of multiple I2C buses, each of which 1956 must have a controller. At any point in time, only one bus is 1957 active. To switch to a different bus, use the 'i2c dev' command. 1958 Note that bus numbering is zero-based. 1959 1960 CONFIG_SYS_I2C_NOPROBES 1961 1962 This option specifies a list of I2C devices that will be skipped 1963 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1964 is set, specify a list of bus-device pairs. Otherwise, specify 1965 a 1D array of device addresses 1966 1967 e.g. 1968 #undef CONFIG_I2C_MULTI_BUS 1969 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1970 1971 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1972 1973 #define CONFIG_I2C_MULTI_BUS 1974 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1975 1976 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1977 1978 CONFIG_SYS_SPD_BUS_NUM 1979 1980 If defined, then this indicates the I2C bus number for DDR SPD. 1981 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1982 1983 CONFIG_SYS_RTC_BUS_NUM 1984 1985 If defined, then this indicates the I2C bus number for the RTC. 1986 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1987 1988 CONFIG_SOFT_I2C_READ_REPEATED_START 1989 1990 defining this will force the i2c_read() function in 1991 the soft_i2c driver to perform an I2C repeated start 1992 between writing the address pointer and reading the 1993 data. If this define is omitted the default behaviour 1994 of doing a stop-start sequence will be used. Most I2C 1995 devices can use either method, but some require one or 1996 the other. 1997 1998- SPI Support: CONFIG_SPI 1999 2000 Enables SPI driver (so far only tested with 2001 SPI EEPROM, also an instance works with Crystal A/D and 2002 D/As on the SACSng board) 2003 2004 CONFIG_SOFT_SPI 2005 2006 Enables a software (bit-bang) SPI driver rather than 2007 using hardware support. This is a general purpose 2008 driver that only requires three general I/O port pins 2009 (two outputs, one input) to function. If this is 2010 defined, the board configuration must define several 2011 SPI configuration items (port pins to use, etc). For 2012 an example, see include/configs/sacsng.h. 2013 2014 CONFIG_HARD_SPI 2015 2016 Enables a hardware SPI driver for general-purpose reads 2017 and writes. As with CONFIG_SOFT_SPI, the board configuration 2018 must define a list of chip-select function pointers. 2019 Currently supported on some MPC8xxx processors. For an 2020 example, see include/configs/mpc8349emds.h. 2021 2022 CONFIG_SYS_SPI_MXC_WAIT 2023 Timeout for waiting until spi transfer completed. 2024 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2025 2026- FPGA Support: CONFIG_FPGA 2027 2028 Enables FPGA subsystem. 2029 2030 CONFIG_FPGA_<vendor> 2031 2032 Enables support for specific chip vendors. 2033 (ALTERA, XILINX) 2034 2035 CONFIG_FPGA_<family> 2036 2037 Enables support for FPGA family. 2038 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2039 2040 CONFIG_FPGA_COUNT 2041 2042 Specify the number of FPGA devices to support. 2043 2044 CONFIG_SYS_FPGA_PROG_FEEDBACK 2045 2046 Enable printing of hash marks during FPGA configuration. 2047 2048 CONFIG_SYS_FPGA_CHECK_BUSY 2049 2050 Enable checks on FPGA configuration interface busy 2051 status by the configuration function. This option 2052 will require a board or device specific function to 2053 be written. 2054 2055 CONFIG_FPGA_DELAY 2056 2057 If defined, a function that provides delays in the FPGA 2058 configuration driver. 2059 2060 CONFIG_SYS_FPGA_CHECK_CTRLC 2061 Allow Control-C to interrupt FPGA configuration 2062 2063 CONFIG_SYS_FPGA_CHECK_ERROR 2064 2065 Check for configuration errors during FPGA bitfile 2066 loading. For example, abort during Virtex II 2067 configuration if the INIT_B line goes low (which 2068 indicated a CRC error). 2069 2070 CONFIG_SYS_FPGA_WAIT_INIT 2071 2072 Maximum time to wait for the INIT_B line to de-assert 2073 after PROB_B has been de-asserted during a Virtex II 2074 FPGA configuration sequence. The default time is 500 2075 ms. 2076 2077 CONFIG_SYS_FPGA_WAIT_BUSY 2078 2079 Maximum time to wait for BUSY to de-assert during 2080 Virtex II FPGA configuration. The default is 5 ms. 2081 2082 CONFIG_SYS_FPGA_WAIT_CONFIG 2083 2084 Time to wait after FPGA configuration. The default is 2085 200 ms. 2086 2087- Configuration Management: 2088 CONFIG_BUILD_TARGET 2089 2090 Some SoCs need special image types (e.g. U-Boot binary 2091 with a special header) as build targets. By defining 2092 CONFIG_BUILD_TARGET in the SoC / board header, this 2093 special image will be automatically built upon calling 2094 make / buildman. 2095 2096 CONFIG_IDENT_STRING 2097 2098 If defined, this string will be added to the U-Boot 2099 version information (U_BOOT_VERSION) 2100 2101- Vendor Parameter Protection: 2102 2103 U-Boot considers the values of the environment 2104 variables "serial#" (Board Serial Number) and 2105 "ethaddr" (Ethernet Address) to be parameters that 2106 are set once by the board vendor / manufacturer, and 2107 protects these variables from casual modification by 2108 the user. Once set, these variables are read-only, 2109 and write or delete attempts are rejected. You can 2110 change this behaviour: 2111 2112 If CONFIG_ENV_OVERWRITE is #defined in your config 2113 file, the write protection for vendor parameters is 2114 completely disabled. Anybody can change or delete 2115 these parameters. 2116 2117 Alternatively, if you define _both_ an ethaddr in the 2118 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2119 Ethernet address is installed in the environment, 2120 which can be changed exactly ONCE by the user. [The 2121 serial# is unaffected by this, i. e. it remains 2122 read-only.] 2123 2124 The same can be accomplished in a more flexible way 2125 for any variable by configuring the type of access 2126 to allow for those variables in the ".flags" variable 2127 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2128 2129- Protected RAM: 2130 CONFIG_PRAM 2131 2132 Define this variable to enable the reservation of 2133 "protected RAM", i. e. RAM which is not overwritten 2134 by U-Boot. Define CONFIG_PRAM to hold the number of 2135 kB you want to reserve for pRAM. You can overwrite 2136 this default value by defining an environment 2137 variable "pram" to the number of kB you want to 2138 reserve. Note that the board info structure will 2139 still show the full amount of RAM. If pRAM is 2140 reserved, a new environment variable "mem" will 2141 automatically be defined to hold the amount of 2142 remaining RAM in a form that can be passed as boot 2143 argument to Linux, for instance like that: 2144 2145 setenv bootargs ... mem=\${mem} 2146 saveenv 2147 2148 This way you can tell Linux not to use this memory, 2149 either, which results in a memory region that will 2150 not be affected by reboots. 2151 2152 *WARNING* If your board configuration uses automatic 2153 detection of the RAM size, you must make sure that 2154 this memory test is non-destructive. So far, the 2155 following board configurations are known to be 2156 "pRAM-clean": 2157 2158 IVMS8, IVML24, SPD8xx, 2159 HERMES, IP860, RPXlite, LWMON, 2160 FLAGADM 2161 2162- Access to physical memory region (> 4GB) 2163 Some basic support is provided for operations on memory not 2164 normally accessible to U-Boot - e.g. some architectures 2165 support access to more than 4GB of memory on 32-bit 2166 machines using physical address extension or similar. 2167 Define CONFIG_PHYSMEM to access this basic support, which 2168 currently only supports clearing the memory. 2169 2170- Error Recovery: 2171 CONFIG_NET_RETRY_COUNT 2172 2173 This variable defines the number of retries for 2174 network operations like ARP, RARP, TFTP, or BOOTP 2175 before giving up the operation. If not defined, a 2176 default value of 5 is used. 2177 2178 CONFIG_ARP_TIMEOUT 2179 2180 Timeout waiting for an ARP reply in milliseconds. 2181 2182 CONFIG_NFS_TIMEOUT 2183 2184 Timeout in milliseconds used in NFS protocol. 2185 If you encounter "ERROR: Cannot umount" in nfs command, 2186 try longer timeout such as 2187 #define CONFIG_NFS_TIMEOUT 10000UL 2188 2189- Command Interpreter: 2190 CONFIG_AUTO_COMPLETE 2191 2192 Enable auto completion of commands using TAB. 2193 2194 CONFIG_SYS_PROMPT_HUSH_PS2 2195 2196 This defines the secondary prompt string, which is 2197 printed when the command interpreter needs more input 2198 to complete a command. Usually "> ". 2199 2200 Note: 2201 2202 In the current implementation, the local variables 2203 space and global environment variables space are 2204 separated. Local variables are those you define by 2205 simply typing `name=value'. To access a local 2206 variable later on, you have write `$name' or 2207 `${name}'; to execute the contents of a variable 2208 directly type `$name' at the command prompt. 2209 2210 Global environment variables are those you use 2211 setenv/printenv to work with. To run a command stored 2212 in such a variable, you need to use the run command, 2213 and you must not use the '$' sign to access them. 2214 2215 To store commands and special characters in a 2216 variable, please use double quotation marks 2217 surrounding the whole text of the variable, instead 2218 of the backslashes before semicolons and special 2219 symbols. 2220 2221- Command Line Editing and History: 2222 CONFIG_CMDLINE_EDITING 2223 2224 Enable editing and History functions for interactive 2225 command line input operations 2226 2227- Command Line PS1/PS2 support: 2228 CONFIG_CMDLINE_PS_SUPPORT 2229 2230 Enable support for changing the command prompt string 2231 at run-time. Only static string is supported so far. 2232 The string is obtained from environment variables PS1 2233 and PS2. 2234 2235- Default Environment: 2236 CONFIG_EXTRA_ENV_SETTINGS 2237 2238 Define this to contain any number of null terminated 2239 strings (variable = value pairs) that will be part of 2240 the default environment compiled into the boot image. 2241 2242 For example, place something like this in your 2243 board's config file: 2244 2245 #define CONFIG_EXTRA_ENV_SETTINGS \ 2246 "myvar1=value1\0" \ 2247 "myvar2=value2\0" 2248 2249 Warning: This method is based on knowledge about the 2250 internal format how the environment is stored by the 2251 U-Boot code. This is NOT an official, exported 2252 interface! Although it is unlikely that this format 2253 will change soon, there is no guarantee either. 2254 You better know what you are doing here. 2255 2256 Note: overly (ab)use of the default environment is 2257 discouraged. Make sure to check other ways to preset 2258 the environment like the "source" command or the 2259 boot command first. 2260 2261 CONFIG_ENV_VARS_UBOOT_CONFIG 2262 2263 Define this in order to add variables describing the 2264 U-Boot build configuration to the default environment. 2265 These will be named arch, cpu, board, vendor, and soc. 2266 2267 Enabling this option will cause the following to be defined: 2268 2269 - CONFIG_SYS_ARCH 2270 - CONFIG_SYS_CPU 2271 - CONFIG_SYS_BOARD 2272 - CONFIG_SYS_VENDOR 2273 - CONFIG_SYS_SOC 2274 2275 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2276 2277 Define this in order to add variables describing certain 2278 run-time determined information about the hardware to the 2279 environment. These will be named board_name, board_rev. 2280 2281 CONFIG_DELAY_ENVIRONMENT 2282 2283 Normally the environment is loaded when the board is 2284 initialised so that it is available to U-Boot. This inhibits 2285 that so that the environment is not available until 2286 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2287 this is instead controlled by the value of 2288 /config/load-environment. 2289 2290- Serial Flash support 2291 Usage requires an initial 'sf probe' to define the serial 2292 flash parameters, followed by read/write/erase/update 2293 commands. 2294 2295 The following defaults may be provided by the platform 2296 to handle the common case when only a single serial 2297 flash is present on the system. 2298 2299 CONFIG_SF_DEFAULT_BUS Bus identifier 2300 CONFIG_SF_DEFAULT_CS Chip-select 2301 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2302 CONFIG_SF_DEFAULT_SPEED in Hz 2303 2304 2305- TFTP Fixed UDP Port: 2306 CONFIG_TFTP_PORT 2307 2308 If this is defined, the environment variable tftpsrcp 2309 is used to supply the TFTP UDP source port value. 2310 If tftpsrcp isn't defined, the normal pseudo-random port 2311 number generator is used. 2312 2313 Also, the environment variable tftpdstp is used to supply 2314 the TFTP UDP destination port value. If tftpdstp isn't 2315 defined, the normal port 69 is used. 2316 2317 The purpose for tftpsrcp is to allow a TFTP server to 2318 blindly start the TFTP transfer using the pre-configured 2319 target IP address and UDP port. This has the effect of 2320 "punching through" the (Windows XP) firewall, allowing 2321 the remainder of the TFTP transfer to proceed normally. 2322 A better solution is to properly configure the firewall, 2323 but sometimes that is not allowed. 2324 2325- bootcount support: 2326 CONFIG_BOOTCOUNT_LIMIT 2327 2328 This enables the bootcounter support, see: 2329 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2330 2331 CONFIG_AT91SAM9XE 2332 enable special bootcounter support on at91sam9xe based boards. 2333 CONFIG_SOC_DA8XX 2334 enable special bootcounter support on da850 based boards. 2335 CONFIG_BOOTCOUNT_RAM 2336 enable support for the bootcounter in RAM 2337 CONFIG_BOOTCOUNT_I2C 2338 enable support for the bootcounter on an i2c (like RTC) device. 2339 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2340 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2341 the bootcounter. 2342 CONFIG_BOOTCOUNT_ALEN = address len 2343 CONFIG_BOOTCOUNT_EXT 2344 enable support for the bootcounter in EXT filesystem 2345 CONFIG_SYS_BOOTCOUNT_ADDR = RAM address used for read 2346 and write. 2347 CONFIG_SYS_BOOTCOUNT_EXT_INTERFACE = interface 2348 CONFIG_SYS_BOOTCOUNT_EXT_DEVPART = device and part 2349 CONFIG_SYS_BOOTCOUNT_EXT_NAME = filename 2350 2351- Show boot progress: 2352 CONFIG_SHOW_BOOT_PROGRESS 2353 2354 Defining this option allows to add some board- 2355 specific code (calling a user-provided function 2356 "show_boot_progress(int)") that enables you to show 2357 the system's boot progress on some display (for 2358 example, some LED's) on your board. At the moment, 2359 the following checkpoints are implemented: 2360 2361 2362Legacy uImage format: 2363 2364 Arg Where When 2365 1 common/cmd_bootm.c before attempting to boot an image 2366 -1 common/cmd_bootm.c Image header has bad magic number 2367 2 common/cmd_bootm.c Image header has correct magic number 2368 -2 common/cmd_bootm.c Image header has bad checksum 2369 3 common/cmd_bootm.c Image header has correct checksum 2370 -3 common/cmd_bootm.c Image data has bad checksum 2371 4 common/cmd_bootm.c Image data has correct checksum 2372 -4 common/cmd_bootm.c Image is for unsupported architecture 2373 5 common/cmd_bootm.c Architecture check OK 2374 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2375 6 common/cmd_bootm.c Image Type check OK 2376 -6 common/cmd_bootm.c gunzip uncompression error 2377 -7 common/cmd_bootm.c Unimplemented compression type 2378 7 common/cmd_bootm.c Uncompression OK 2379 8 common/cmd_bootm.c No uncompress/copy overwrite error 2380 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2381 2382 9 common/image.c Start initial ramdisk verification 2383 -10 common/image.c Ramdisk header has bad magic number 2384 -11 common/image.c Ramdisk header has bad checksum 2385 10 common/image.c Ramdisk header is OK 2386 -12 common/image.c Ramdisk data has bad checksum 2387 11 common/image.c Ramdisk data has correct checksum 2388 12 common/image.c Ramdisk verification complete, start loading 2389 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2390 13 common/image.c Start multifile image verification 2391 14 common/image.c No initial ramdisk, no multifile, continue. 2392 2393 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2394 2395 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2396 -31 post/post.c POST test failed, detected by post_output_backlog() 2397 -32 post/post.c POST test failed, detected by post_run_single() 2398 2399 34 common/cmd_doc.c before loading a Image from a DOC device 2400 -35 common/cmd_doc.c Bad usage of "doc" command 2401 35 common/cmd_doc.c correct usage of "doc" command 2402 -36 common/cmd_doc.c No boot device 2403 36 common/cmd_doc.c correct boot device 2404 -37 common/cmd_doc.c Unknown Chip ID on boot device 2405 37 common/cmd_doc.c correct chip ID found, device available 2406 -38 common/cmd_doc.c Read Error on boot device 2407 38 common/cmd_doc.c reading Image header from DOC device OK 2408 -39 common/cmd_doc.c Image header has bad magic number 2409 39 common/cmd_doc.c Image header has correct magic number 2410 -40 common/cmd_doc.c Error reading Image from DOC device 2411 40 common/cmd_doc.c Image header has correct magic number 2412 41 common/cmd_ide.c before loading a Image from a IDE device 2413 -42 common/cmd_ide.c Bad usage of "ide" command 2414 42 common/cmd_ide.c correct usage of "ide" command 2415 -43 common/cmd_ide.c No boot device 2416 43 common/cmd_ide.c boot device found 2417 -44 common/cmd_ide.c Device not available 2418 44 common/cmd_ide.c Device available 2419 -45 common/cmd_ide.c wrong partition selected 2420 45 common/cmd_ide.c partition selected 2421 -46 common/cmd_ide.c Unknown partition table 2422 46 common/cmd_ide.c valid partition table found 2423 -47 common/cmd_ide.c Invalid partition type 2424 47 common/cmd_ide.c correct partition type 2425 -48 common/cmd_ide.c Error reading Image Header on boot device 2426 48 common/cmd_ide.c reading Image Header from IDE device OK 2427 -49 common/cmd_ide.c Image header has bad magic number 2428 49 common/cmd_ide.c Image header has correct magic number 2429 -50 common/cmd_ide.c Image header has bad checksum 2430 50 common/cmd_ide.c Image header has correct checksum 2431 -51 common/cmd_ide.c Error reading Image from IDE device 2432 51 common/cmd_ide.c reading Image from IDE device OK 2433 52 common/cmd_nand.c before loading a Image from a NAND device 2434 -53 common/cmd_nand.c Bad usage of "nand" command 2435 53 common/cmd_nand.c correct usage of "nand" command 2436 -54 common/cmd_nand.c No boot device 2437 54 common/cmd_nand.c boot device found 2438 -55 common/cmd_nand.c Unknown Chip ID on boot device 2439 55 common/cmd_nand.c correct chip ID found, device available 2440 -56 common/cmd_nand.c Error reading Image Header on boot device 2441 56 common/cmd_nand.c reading Image Header from NAND device OK 2442 -57 common/cmd_nand.c Image header has bad magic number 2443 57 common/cmd_nand.c Image header has correct magic number 2444 -58 common/cmd_nand.c Error reading Image from NAND device 2445 58 common/cmd_nand.c reading Image from NAND device OK 2446 2447 -60 common/env_common.c Environment has a bad CRC, using default 2448 2449 64 net/eth.c starting with Ethernet configuration. 2450 -64 net/eth.c no Ethernet found. 2451 65 net/eth.c Ethernet found. 2452 2453 -80 common/cmd_net.c usage wrong 2454 80 common/cmd_net.c before calling net_loop() 2455 -81 common/cmd_net.c some error in net_loop() occurred 2456 81 common/cmd_net.c net_loop() back without error 2457 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2458 82 common/cmd_net.c trying automatic boot 2459 83 common/cmd_net.c running "source" command 2460 -83 common/cmd_net.c some error in automatic boot or "source" command 2461 84 common/cmd_net.c end without errors 2462 2463FIT uImage format: 2464 2465 Arg Where When 2466 100 common/cmd_bootm.c Kernel FIT Image has correct format 2467 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2468 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2469 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2470 102 common/cmd_bootm.c Kernel unit name specified 2471 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2472 103 common/cmd_bootm.c Found configuration node 2473 104 common/cmd_bootm.c Got kernel subimage node offset 2474 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2475 105 common/cmd_bootm.c Kernel subimage hash verification OK 2476 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2477 106 common/cmd_bootm.c Architecture check OK 2478 -106 common/cmd_bootm.c Kernel subimage has wrong type 2479 107 common/cmd_bootm.c Kernel subimage type OK 2480 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2481 108 common/cmd_bootm.c Got kernel subimage data/size 2482 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2483 -109 common/cmd_bootm.c Can't get kernel subimage type 2484 -110 common/cmd_bootm.c Can't get kernel subimage comp 2485 -111 common/cmd_bootm.c Can't get kernel subimage os 2486 -112 common/cmd_bootm.c Can't get kernel subimage load address 2487 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2488 2489 120 common/image.c Start initial ramdisk verification 2490 -120 common/image.c Ramdisk FIT image has incorrect format 2491 121 common/image.c Ramdisk FIT image has correct format 2492 122 common/image.c No ramdisk subimage unit name, using configuration 2493 -122 common/image.c Can't get configuration for ramdisk subimage 2494 123 common/image.c Ramdisk unit name specified 2495 -124 common/image.c Can't get ramdisk subimage node offset 2496 125 common/image.c Got ramdisk subimage node offset 2497 -125 common/image.c Ramdisk subimage hash verification failed 2498 126 common/image.c Ramdisk subimage hash verification OK 2499 -126 common/image.c Ramdisk subimage for unsupported architecture 2500 127 common/image.c Architecture check OK 2501 -127 common/image.c Can't get ramdisk subimage data/size 2502 128 common/image.c Got ramdisk subimage data/size 2503 129 common/image.c Can't get ramdisk load address 2504 -129 common/image.c Got ramdisk load address 2505 2506 -130 common/cmd_doc.c Incorrect FIT image format 2507 131 common/cmd_doc.c FIT image format OK 2508 2509 -140 common/cmd_ide.c Incorrect FIT image format 2510 141 common/cmd_ide.c FIT image format OK 2511 2512 -150 common/cmd_nand.c Incorrect FIT image format 2513 151 common/cmd_nand.c FIT image format OK 2514 2515- legacy image format: 2516 CONFIG_IMAGE_FORMAT_LEGACY 2517 enables the legacy image format support in U-Boot. 2518 2519 Default: 2520 enabled if CONFIG_FIT_SIGNATURE is not defined. 2521 2522 CONFIG_DISABLE_IMAGE_LEGACY 2523 disable the legacy image format 2524 2525 This define is introduced, as the legacy image format is 2526 enabled per default for backward compatibility. 2527 2528- Standalone program support: 2529 CONFIG_STANDALONE_LOAD_ADDR 2530 2531 This option defines a board specific value for the 2532 address where standalone program gets loaded, thus 2533 overwriting the architecture dependent default 2534 settings. 2535 2536- Frame Buffer Address: 2537 CONFIG_FB_ADDR 2538 2539 Define CONFIG_FB_ADDR if you want to use specific 2540 address for frame buffer. This is typically the case 2541 when using a graphics controller has separate video 2542 memory. U-Boot will then place the frame buffer at 2543 the given address instead of dynamically reserving it 2544 in system RAM by calling lcd_setmem(), which grabs 2545 the memory for the frame buffer depending on the 2546 configured panel size. 2547 2548 Please see board_init_f function. 2549 2550- Automatic software updates via TFTP server 2551 CONFIG_UPDATE_TFTP 2552 CONFIG_UPDATE_TFTP_CNT_MAX 2553 CONFIG_UPDATE_TFTP_MSEC_MAX 2554 2555 These options enable and control the auto-update feature; 2556 for a more detailed description refer to doc/README.update. 2557 2558- MTD Support (mtdparts command, UBI support) 2559 CONFIG_MTD_DEVICE 2560 2561 Adds the MTD device infrastructure from the Linux kernel. 2562 Needed for mtdparts command support. 2563 2564 CONFIG_MTD_PARTITIONS 2565 2566 Adds the MTD partitioning infrastructure from the Linux 2567 kernel. Needed for UBI support. 2568 2569- UBI support 2570 CONFIG_UBI_SILENCE_MSG 2571 2572 Make the verbose messages from UBI stop printing. This leaves 2573 warnings and errors enabled. 2574 2575 2576 CONFIG_MTD_UBI_WL_THRESHOLD 2577 This parameter defines the maximum difference between the highest 2578 erase counter value and the lowest erase counter value of eraseblocks 2579 of UBI devices. When this threshold is exceeded, UBI starts performing 2580 wear leveling by means of moving data from eraseblock with low erase 2581 counter to eraseblocks with high erase counter. 2582 2583 The default value should be OK for SLC NAND flashes, NOR flashes and 2584 other flashes which have eraseblock life-cycle 100000 or more. 2585 However, in case of MLC NAND flashes which typically have eraseblock 2586 life-cycle less than 10000, the threshold should be lessened (e.g., 2587 to 128 or 256, although it does not have to be power of 2). 2588 2589 default: 4096 2590 2591 CONFIG_MTD_UBI_BEB_LIMIT 2592 This option specifies the maximum bad physical eraseblocks UBI 2593 expects on the MTD device (per 1024 eraseblocks). If the 2594 underlying flash does not admit of bad eraseblocks (e.g. NOR 2595 flash), this value is ignored. 2596 2597 NAND datasheets often specify the minimum and maximum NVM 2598 (Number of Valid Blocks) for the flashes' endurance lifetime. 2599 The maximum expected bad eraseblocks per 1024 eraseblocks 2600 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 2601 which gives 20 for most NANDs (MaxNVB is basically the total 2602 count of eraseblocks on the chip). 2603 2604 To put it differently, if this value is 20, UBI will try to 2605 reserve about 1.9% of physical eraseblocks for bad blocks 2606 handling. And that will be 1.9% of eraseblocks on the entire 2607 NAND chip, not just the MTD partition UBI attaches. This means 2608 that if you have, say, a NAND flash chip admits maximum 40 bad 2609 eraseblocks, and it is split on two MTD partitions of the same 2610 size, UBI will reserve 40 eraseblocks when attaching a 2611 partition. 2612 2613 default: 20 2614 2615 CONFIG_MTD_UBI_FASTMAP 2616 Fastmap is a mechanism which allows attaching an UBI device 2617 in nearly constant time. Instead of scanning the whole MTD device it 2618 only has to locate a checkpoint (called fastmap) on the device. 2619 The on-flash fastmap contains all information needed to attach 2620 the device. Using fastmap makes only sense on large devices where 2621 attaching by scanning takes long. UBI will not automatically install 2622 a fastmap on old images, but you can set the UBI parameter 2623 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 2624 that fastmap-enabled images are still usable with UBI implementations 2625 without fastmap support. On typical flash devices the whole fastmap 2626 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 2627 2628 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 2629 Set this parameter to enable fastmap automatically on images 2630 without a fastmap. 2631 default: 0 2632 2633 CONFIG_MTD_UBI_FM_DEBUG 2634 Enable UBI fastmap debug 2635 default: 0 2636 2637- UBIFS support 2638 CONFIG_UBIFS_SILENCE_MSG 2639 2640 Make the verbose messages from UBIFS stop printing. This leaves 2641 warnings and errors enabled. 2642 2643- SPL framework 2644 CONFIG_SPL 2645 Enable building of SPL globally. 2646 2647 CONFIG_SPL_LDSCRIPT 2648 LDSCRIPT for linking the SPL binary. 2649 2650 CONFIG_SPL_MAX_FOOTPRINT 2651 Maximum size in memory allocated to the SPL, BSS included. 2652 When defined, the linker checks that the actual memory 2653 used by SPL from _start to __bss_end does not exceed it. 2654 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 2655 must not be both defined at the same time. 2656 2657 CONFIG_SPL_MAX_SIZE 2658 Maximum size of the SPL image (text, data, rodata, and 2659 linker lists sections), BSS excluded. 2660 When defined, the linker checks that the actual size does 2661 not exceed it. 2662 2663 CONFIG_SPL_TEXT_BASE 2664 TEXT_BASE for linking the SPL binary. 2665 2666 CONFIG_SPL_RELOC_TEXT_BASE 2667 Address to relocate to. If unspecified, this is equal to 2668 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 2669 2670 CONFIG_SPL_BSS_START_ADDR 2671 Link address for the BSS within the SPL binary. 2672 2673 CONFIG_SPL_BSS_MAX_SIZE 2674 Maximum size in memory allocated to the SPL BSS. 2675 When defined, the linker checks that the actual memory used 2676 by SPL from __bss_start to __bss_end does not exceed it. 2677 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 2678 must not be both defined at the same time. 2679 2680 CONFIG_SPL_STACK 2681 Adress of the start of the stack SPL will use 2682 2683 CONFIG_SPL_PANIC_ON_RAW_IMAGE 2684 When defined, SPL will panic() if the image it has 2685 loaded does not have a signature. 2686 Defining this is useful when code which loads images 2687 in SPL cannot guarantee that absolutely all read errors 2688 will be caught. 2689 An example is the LPC32XX MLC NAND driver, which will 2690 consider that a completely unreadable NAND block is bad, 2691 and thus should be skipped silently. 2692 2693 CONFIG_SPL_RELOC_STACK 2694 Adress of the start of the stack SPL will use after 2695 relocation. If unspecified, this is equal to 2696 CONFIG_SPL_STACK. 2697 2698 CONFIG_SYS_SPL_MALLOC_START 2699 Starting address of the malloc pool used in SPL. 2700 When this option is set the full malloc is used in SPL and 2701 it is set up by spl_init() and before that, the simple malloc() 2702 can be used if CONFIG_SYS_MALLOC_F is defined. 2703 2704 CONFIG_SYS_SPL_MALLOC_SIZE 2705 The size of the malloc pool used in SPL. 2706 2707 CONFIG_SPL_OS_BOOT 2708 Enable booting directly to an OS from SPL. 2709 See also: doc/README.falcon 2710 2711 CONFIG_SPL_DISPLAY_PRINT 2712 For ARM, enable an optional function to print more information 2713 about the running system. 2714 2715 CONFIG_SPL_INIT_MINIMAL 2716 Arch init code should be built for a very small image 2717 2718 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 2719 Partition on the MMC to load U-Boot from when the MMC is being 2720 used in raw mode 2721 2722 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 2723 Sector to load kernel uImage from when MMC is being 2724 used in raw mode (for Falcon mode) 2725 2726 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 2727 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 2728 Sector and number of sectors to load kernel argument 2729 parameters from when MMC is being used in raw mode 2730 (for falcon mode) 2731 2732 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 2733 Partition on the MMC to load U-Boot from when the MMC is being 2734 used in fs mode 2735 2736 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 2737 Filename to read to load U-Boot when reading from filesystem 2738 2739 CONFIG_SPL_FS_LOAD_KERNEL_NAME 2740 Filename to read to load kernel uImage when reading 2741 from filesystem (for Falcon mode) 2742 2743 CONFIG_SPL_FS_LOAD_ARGS_NAME 2744 Filename to read to load kernel argument parameters 2745 when reading from filesystem (for Falcon mode) 2746 2747 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 2748 Set this for NAND SPL on PPC mpc83xx targets, so that 2749 start.S waits for the rest of the SPL to load before 2750 continuing (the hardware starts execution after just 2751 loading the first page rather than the full 4K). 2752 2753 CONFIG_SPL_SKIP_RELOCATE 2754 Avoid SPL relocation 2755 2756 CONFIG_SPL_NAND_BASE 2757 Include nand_base.c in the SPL. Requires 2758 CONFIG_SPL_NAND_DRIVERS. 2759 2760 CONFIG_SPL_NAND_DRIVERS 2761 SPL uses normal NAND drivers, not minimal drivers. 2762 2763 CONFIG_SPL_NAND_ECC 2764 Include standard software ECC in the SPL 2765 2766 CONFIG_SPL_NAND_SIMPLE 2767 Support for NAND boot using simple NAND drivers that 2768 expose the cmd_ctrl() interface. 2769 2770 CONFIG_SPL_UBI 2771 Support for a lightweight UBI (fastmap) scanner and 2772 loader 2773 2774 CONFIG_SPL_NAND_RAW_ONLY 2775 Support to boot only raw u-boot.bin images. Use this only 2776 if you need to save space. 2777 2778 CONFIG_SPL_COMMON_INIT_DDR 2779 Set for common ddr init with serial presence detect in 2780 SPL binary. 2781 2782 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 2783 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 2784 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 2785 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 2786 CONFIG_SYS_NAND_ECCBYTES 2787 Defines the size and behavior of the NAND that SPL uses 2788 to read U-Boot 2789 2790 CONFIG_SPL_NAND_BOOT 2791 Add support NAND boot 2792 2793 CONFIG_SYS_NAND_U_BOOT_OFFS 2794 Location in NAND to read U-Boot from 2795 2796 CONFIG_SYS_NAND_U_BOOT_DST 2797 Location in memory to load U-Boot to 2798 2799 CONFIG_SYS_NAND_U_BOOT_SIZE 2800 Size of image to load 2801 2802 CONFIG_SYS_NAND_U_BOOT_START 2803 Entry point in loaded image to jump to 2804 2805 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 2806 Define this if you need to first read the OOB and then the 2807 data. This is used, for example, on davinci platforms. 2808 2809 CONFIG_SPL_RAM_DEVICE 2810 Support for running image already present in ram, in SPL binary 2811 2812 CONFIG_SPL_PAD_TO 2813 Image offset to which the SPL should be padded before appending 2814 the SPL payload. By default, this is defined as 2815 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 2816 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 2817 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 2818 2819 CONFIG_SPL_TARGET 2820 Final target image containing SPL and payload. Some SPLs 2821 use an arch-specific makefile fragment instead, for 2822 example if more than one image needs to be produced. 2823 2824 CONFIG_FIT_SPL_PRINT 2825 Printing information about a FIT image adds quite a bit of 2826 code to SPL. So this is normally disabled in SPL. Use this 2827 option to re-enable it. This will affect the output of the 2828 bootm command when booting a FIT image. 2829 2830- TPL framework 2831 CONFIG_TPL 2832 Enable building of TPL globally. 2833 2834 CONFIG_TPL_PAD_TO 2835 Image offset to which the TPL should be padded before appending 2836 the TPL payload. By default, this is defined as 2837 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 2838 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 2839 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 2840 2841- Interrupt support (PPC): 2842 2843 There are common interrupt_init() and timer_interrupt() 2844 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2845 for CPU specific initialization. interrupt_init_cpu() 2846 should set decrementer_count to appropriate value. If 2847 CPU resets decrementer automatically after interrupt 2848 (ppc4xx) it should set decrementer_count to zero. 2849 timer_interrupt() calls timer_interrupt_cpu() for CPU 2850 specific handling. If board has watchdog / status_led 2851 / other_activity_monitor it works automatically from 2852 general timer_interrupt(). 2853 2854 2855Board initialization settings: 2856------------------------------ 2857 2858During Initialization u-boot calls a number of board specific functions 2859to allow the preparation of board specific prerequisites, e.g. pin setup 2860before drivers are initialized. To enable these callbacks the 2861following configuration macros have to be defined. Currently this is 2862architecture specific, so please check arch/your_architecture/lib/board.c 2863typically in board_init_f() and board_init_r(). 2864 2865- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 2866- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 2867- CONFIG_BOARD_LATE_INIT: Call board_late_init() 2868- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 2869 2870Configuration Settings: 2871----------------------- 2872 2873- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 2874 Optionally it can be defined to support 64-bit memory commands. 2875 2876- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2877 undefine this when you're short of memory. 2878 2879- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2880 width of the commands listed in the 'help' command output. 2881 2882- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2883 prompt for user input. 2884 2885- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2886 2887- CONFIG_SYS_PBSIZE: Buffer size for Console output 2888 2889- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2890 2891- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2892 the application (usually a Linux kernel) when it is 2893 booted 2894 2895- CONFIG_SYS_BAUDRATE_TABLE: 2896 List of legal baudrate settings for this board. 2897 2898- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2899 Begin and End addresses of the area used by the 2900 simple memory test. 2901 2902- CONFIG_SYS_ALT_MEMTEST: 2903 Enable an alternate, more extensive memory test. 2904 2905- CONFIG_SYS_MEMTEST_SCRATCH: 2906 Scratch address used by the alternate memory test 2907 You only need to set this if address zero isn't writeable 2908 2909- CONFIG_SYS_MEM_RESERVE_SECURE 2910 Only implemented for ARMv8 for now. 2911 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 2912 is substracted from total RAM and won't be reported to OS. 2913 This memory can be used as secure memory. A variable 2914 gd->arch.secure_ram is used to track the location. In systems 2915 the RAM base is not zero, or RAM is divided into banks, 2916 this variable needs to be recalcuated to get the address. 2917 2918- CONFIG_SYS_MEM_TOP_HIDE: 2919 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 2920 this specified memory area will get subtracted from the top 2921 (end) of RAM and won't get "touched" at all by U-Boot. By 2922 fixing up gd->ram_size the Linux kernel should gets passed 2923 the now "corrected" memory size and won't touch it either. 2924 This should work for arch/ppc and arch/powerpc. Only Linux 2925 board ports in arch/powerpc with bootwrapper support that 2926 recalculate the memory size from the SDRAM controller setup 2927 will have to get fixed in Linux additionally. 2928 2929 This option can be used as a workaround for the 440EPx/GRx 2930 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 2931 be touched. 2932 2933 WARNING: Please make sure that this value is a multiple of 2934 the Linux page size (normally 4k). If this is not the case, 2935 then the end address of the Linux memory will be located at a 2936 non page size aligned address and this could cause major 2937 problems. 2938 2939- CONFIG_SYS_LOADS_BAUD_CHANGE: 2940 Enable temporary baudrate change while serial download 2941 2942- CONFIG_SYS_SDRAM_BASE: 2943 Physical start address of SDRAM. _Must_ be 0 here. 2944 2945- CONFIG_SYS_FLASH_BASE: 2946 Physical start address of Flash memory. 2947 2948- CONFIG_SYS_MONITOR_BASE: 2949 Physical start address of boot monitor code (set by 2950 make config files to be same as the text base address 2951 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 2952 CONFIG_SYS_FLASH_BASE when booting from flash. 2953 2954- CONFIG_SYS_MONITOR_LEN: 2955 Size of memory reserved for monitor code, used to 2956 determine _at_compile_time_ (!) if the environment is 2957 embedded within the U-Boot image, or in a separate 2958 flash sector. 2959 2960- CONFIG_SYS_MALLOC_LEN: 2961 Size of DRAM reserved for malloc() use. 2962 2963- CONFIG_SYS_MALLOC_F_LEN 2964 Size of the malloc() pool for use before relocation. If 2965 this is defined, then a very simple malloc() implementation 2966 will become available before relocation. The address is just 2967 below the global data, and the stack is moved down to make 2968 space. 2969 2970 This feature allocates regions with increasing addresses 2971 within the region. calloc() is supported, but realloc() 2972 is not available. free() is supported but does nothing. 2973 The memory will be freed (or in fact just forgotten) when 2974 U-Boot relocates itself. 2975 2976- CONFIG_SYS_MALLOC_SIMPLE 2977 Provides a simple and small malloc() and calloc() for those 2978 boards which do not use the full malloc in SPL (which is 2979 enabled with CONFIG_SYS_SPL_MALLOC_START). 2980 2981- CONFIG_SYS_NONCACHED_MEMORY: 2982 Size of non-cached memory area. This area of memory will be 2983 typically located right below the malloc() area and mapped 2984 uncached in the MMU. This is useful for drivers that would 2985 otherwise require a lot of explicit cache maintenance. For 2986 some drivers it's also impossible to properly maintain the 2987 cache. For example if the regions that need to be flushed 2988 are not a multiple of the cache-line size, *and* padding 2989 cannot be allocated between the regions to align them (i.e. 2990 if the HW requires a contiguous array of regions, and the 2991 size of each region is not cache-aligned), then a flush of 2992 one region may result in overwriting data that hardware has 2993 written to another region in the same cache-line. This can 2994 happen for example in network drivers where descriptors for 2995 buffers are typically smaller than the CPU cache-line (e.g. 2996 16 bytes vs. 32 or 64 bytes). 2997 2998 Non-cached memory is only supported on 32-bit ARM at present. 2999 3000- CONFIG_SYS_BOOTM_LEN: 3001 Normally compressed uImages are limited to an 3002 uncompressed size of 8 MBytes. If this is not enough, 3003 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3004 to adjust this setting to your needs. 3005 3006- CONFIG_SYS_BOOTMAPSZ: 3007 Maximum size of memory mapped by the startup code of 3008 the Linux kernel; all data that must be processed by 3009 the Linux kernel (bd_info, boot arguments, FDT blob if 3010 used) must be put below this limit, unless "bootm_low" 3011 environment variable is defined and non-zero. In such case 3012 all data for the Linux kernel must be between "bootm_low" 3013 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3014 variable "bootm_mapsize" will override the value of 3015 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3016 then the value in "bootm_size" will be used instead. 3017 3018- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3019 Enable initrd_high functionality. If defined then the 3020 initrd_high feature is enabled and the bootm ramdisk subcommand 3021 is enabled. 3022 3023- CONFIG_SYS_BOOT_GET_CMDLINE: 3024 Enables allocating and saving kernel cmdline in space between 3025 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3026 3027- CONFIG_SYS_BOOT_GET_KBD: 3028 Enables allocating and saving a kernel copy of the bd_info in 3029 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3030 3031- CONFIG_SYS_MAX_FLASH_BANKS: 3032 Max number of Flash memory banks 3033 3034- CONFIG_SYS_MAX_FLASH_SECT: 3035 Max number of sectors on a Flash chip 3036 3037- CONFIG_SYS_FLASH_ERASE_TOUT: 3038 Timeout for Flash erase operations (in ms) 3039 3040- CONFIG_SYS_FLASH_WRITE_TOUT: 3041 Timeout for Flash write operations (in ms) 3042 3043- CONFIG_SYS_FLASH_LOCK_TOUT 3044 Timeout for Flash set sector lock bit operation (in ms) 3045 3046- CONFIG_SYS_FLASH_UNLOCK_TOUT 3047 Timeout for Flash clear lock bits operation (in ms) 3048 3049- CONFIG_SYS_FLASH_PROTECTION 3050 If defined, hardware flash sectors protection is used 3051 instead of U-Boot software protection. 3052 3053- CONFIG_SYS_DIRECT_FLASH_TFTP: 3054 3055 Enable TFTP transfers directly to flash memory; 3056 without this option such a download has to be 3057 performed in two steps: (1) download to RAM, and (2) 3058 copy from RAM to flash. 3059 3060 The two-step approach is usually more reliable, since 3061 you can check if the download worked before you erase 3062 the flash, but in some situations (when system RAM is 3063 too limited to allow for a temporary copy of the 3064 downloaded image) this option may be very useful. 3065 3066- CONFIG_SYS_FLASH_CFI: 3067 Define if the flash driver uses extra elements in the 3068 common flash structure for storing flash geometry. 3069 3070- CONFIG_FLASH_CFI_DRIVER 3071 This option also enables the building of the cfi_flash driver 3072 in the drivers directory 3073 3074- CONFIG_FLASH_CFI_MTD 3075 This option enables the building of the cfi_mtd driver 3076 in the drivers directory. The driver exports CFI flash 3077 to the MTD layer. 3078 3079- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3080 Use buffered writes to flash. 3081 3082- CONFIG_FLASH_SPANSION_S29WS_N 3083 s29ws-n MirrorBit flash has non-standard addresses for buffered 3084 write commands. 3085 3086- CONFIG_SYS_FLASH_QUIET_TEST 3087 If this option is defined, the common CFI flash doesn't 3088 print it's warning upon not recognized FLASH banks. This 3089 is useful, if some of the configured banks are only 3090 optionally available. 3091 3092- CONFIG_FLASH_SHOW_PROGRESS 3093 If defined (must be an integer), print out countdown 3094 digits and dots. Recommended value: 45 (9..1) for 80 3095 column displays, 15 (3..1) for 40 column displays. 3096 3097- CONFIG_FLASH_VERIFY 3098 If defined, the content of the flash (destination) is compared 3099 against the source after the write operation. An error message 3100 will be printed when the contents are not identical. 3101 Please note that this option is useless in nearly all cases, 3102 since such flash programming errors usually are detected earlier 3103 while unprotecting/erasing/programming. Please only enable 3104 this option if you really know what you are doing. 3105 3106- CONFIG_SYS_RX_ETH_BUFFER: 3107 Defines the number of Ethernet receive buffers. On some 3108 Ethernet controllers it is recommended to set this value 3109 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3110 buffers can be full shortly after enabling the interface 3111 on high Ethernet traffic. 3112 Defaults to 4 if not defined. 3113 3114- CONFIG_ENV_MAX_ENTRIES 3115 3116 Maximum number of entries in the hash table that is used 3117 internally to store the environment settings. The default 3118 setting is supposed to be generous and should work in most 3119 cases. This setting can be used to tune behaviour; see 3120 lib/hashtable.c for details. 3121 3122- CONFIG_ENV_FLAGS_LIST_DEFAULT 3123- CONFIG_ENV_FLAGS_LIST_STATIC 3124 Enable validation of the values given to environment variables when 3125 calling env set. Variables can be restricted to only decimal, 3126 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3127 the variables can also be restricted to IP address or MAC address. 3128 3129 The format of the list is: 3130 type_attribute = [s|d|x|b|i|m] 3131 access_attribute = [a|r|o|c] 3132 attributes = type_attribute[access_attribute] 3133 entry = variable_name[:attributes] 3134 list = entry[,list] 3135 3136 The type attributes are: 3137 s - String (default) 3138 d - Decimal 3139 x - Hexadecimal 3140 b - Boolean ([1yYtT|0nNfF]) 3141 i - IP address 3142 m - MAC address 3143 3144 The access attributes are: 3145 a - Any (default) 3146 r - Read-only 3147 o - Write-once 3148 c - Change-default 3149 3150 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3151 Define this to a list (string) to define the ".flags" 3152 environment variable in the default or embedded environment. 3153 3154 - CONFIG_ENV_FLAGS_LIST_STATIC 3155 Define this to a list (string) to define validation that 3156 should be done if an entry is not found in the ".flags" 3157 environment variable. To override a setting in the static 3158 list, simply add an entry for the same variable name to the 3159 ".flags" variable. 3160 3161 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3162 regular expression. This allows multiple variables to define the same 3163 flags without explicitly listing them for each variable. 3164 3165- CONFIG_ENV_ACCESS_IGNORE_FORCE 3166 If defined, don't allow the -f switch to env set override variable 3167 access flags. 3168 3169- CONFIG_USE_STDINT 3170 If stdint.h is available with your toolchain you can define this 3171 option to enable it. You can provide option 'USE_STDINT=1' when 3172 building U-Boot to enable this. 3173 3174The following definitions that deal with the placement and management 3175of environment data (variable area); in general, we support the 3176following configurations: 3177 3178- CONFIG_BUILD_ENVCRC: 3179 3180 Builds up envcrc with the target environment so that external utils 3181 may easily extract it and embed it in final U-Boot images. 3182 3183BE CAREFUL! The first access to the environment happens quite early 3184in U-Boot initialization (when we try to get the setting of for the 3185console baudrate). You *MUST* have mapped your NVRAM area then, or 3186U-Boot will hang. 3187 3188Please note that even with NVRAM we still use a copy of the 3189environment in RAM: we could work on NVRAM directly, but we want to 3190keep settings there always unmodified except somebody uses "saveenv" 3191to save the current settings. 3192 3193BE CAREFUL! For some special cases, the local device can not use 3194"saveenv" command. For example, the local device will get the 3195environment stored in a remote NOR flash by SRIO or PCIE link, 3196but it can not erase, write this NOR flash by SRIO or PCIE interface. 3197 3198- CONFIG_NAND_ENV_DST 3199 3200 Defines address in RAM to which the nand_spl code should copy the 3201 environment. If redundant environment is used, it will be copied to 3202 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3203 3204Please note that the environment is read-only until the monitor 3205has been relocated to RAM and a RAM copy of the environment has been 3206created; also, when using EEPROM you will have to use env_get_f() 3207until then to read environment variables. 3208 3209The environment is protected by a CRC32 checksum. Before the monitor 3210is relocated into RAM, as a result of a bad CRC you will be working 3211with the compiled-in default environment - *silently*!!! [This is 3212necessary, because the first environment variable we need is the 3213"baudrate" setting for the console - if we have a bad CRC, we don't 3214have any device yet where we could complain.] 3215 3216Note: once the monitor has been relocated, then it will complain if 3217the default environment is used; a new CRC is computed as soon as you 3218use the "saveenv" command to store a valid environment. 3219 3220- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 3221 Echo the inverted Ethernet link state to the fault LED. 3222 3223 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 3224 also needs to be defined. 3225 3226- CONFIG_SYS_FAULT_MII_ADDR: 3227 MII address of the PHY to check for the Ethernet link state. 3228 3229- CONFIG_NS16550_MIN_FUNCTIONS: 3230 Define this if you desire to only have use of the NS16550_init 3231 and NS16550_putc functions for the serial driver located at 3232 drivers/serial/ns16550.c. This option is useful for saving 3233 space for already greatly restricted images, including but not 3234 limited to NAND_SPL configurations. 3235 3236- CONFIG_DISPLAY_BOARDINFO 3237 Display information about the board that U-Boot is running on 3238 when U-Boot starts up. The board function checkboard() is called 3239 to do this. 3240 3241- CONFIG_DISPLAY_BOARDINFO_LATE 3242 Similar to the previous option, but display this information 3243 later, once stdio is running and output goes to the LCD, if 3244 present. 3245 3246- CONFIG_BOARD_SIZE_LIMIT: 3247 Maximum size of the U-Boot image. When defined, the 3248 build system checks that the actual size does not 3249 exceed it. 3250 3251Low Level (hardware related) configuration options: 3252--------------------------------------------------- 3253 3254- CONFIG_SYS_CACHELINE_SIZE: 3255 Cache Line Size of the CPU. 3256 3257- CONFIG_SYS_CCSRBAR_DEFAULT: 3258 Default (power-on reset) physical address of CCSR on Freescale 3259 PowerPC SOCs. 3260 3261- CONFIG_SYS_CCSRBAR: 3262 Virtual address of CCSR. On a 32-bit build, this is typically 3263 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3264 3265- CONFIG_SYS_CCSRBAR_PHYS: 3266 Physical address of CCSR. CCSR can be relocated to a new 3267 physical address, if desired. In this case, this macro should 3268 be set to that address. Otherwise, it should be set to the 3269 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3270 is typically relocated on 36-bit builds. It is recommended 3271 that this macro be defined via the _HIGH and _LOW macros: 3272 3273 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3274 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3275 3276- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3277 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3278 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3279 used in assembly code, so it must not contain typecasts or 3280 integer size suffixes (e.g. "ULL"). 3281 3282- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3283 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3284 used in assembly code, so it must not contain typecasts or 3285 integer size suffixes (e.g. "ULL"). 3286 3287- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3288 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3289 forced to a value that ensures that CCSR is not relocated. 3290 3291- Floppy Disk Support: 3292 CONFIG_SYS_FDC_DRIVE_NUMBER 3293 3294 the default drive number (default value 0) 3295 3296 CONFIG_SYS_ISA_IO_STRIDE 3297 3298 defines the spacing between FDC chipset registers 3299 (default value 1) 3300 3301 CONFIG_SYS_ISA_IO_OFFSET 3302 3303 defines the offset of register from address. It 3304 depends on which part of the data bus is connected to 3305 the FDC chipset. (default value 0) 3306 3307 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3308 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3309 default value. 3310 3311 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3312 fdc_hw_init() is called at the beginning of the FDC 3313 setup. fdc_hw_init() must be provided by the board 3314 source code. It is used to make hardware-dependent 3315 initializations. 3316 3317- CONFIG_IDE_AHB: 3318 Most IDE controllers were designed to be connected with PCI 3319 interface. Only few of them were designed for AHB interface. 3320 When software is doing ATA command and data transfer to 3321 IDE devices through IDE-AHB controller, some additional 3322 registers accessing to these kind of IDE-AHB controller 3323 is required. 3324 3325- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3326 DO NOT CHANGE unless you know exactly what you're 3327 doing! (11-4) [MPC8xx systems only] 3328 3329- CONFIG_SYS_INIT_RAM_ADDR: 3330 3331 Start address of memory area that can be used for 3332 initial data and stack; please note that this must be 3333 writable memory that is working WITHOUT special 3334 initialization, i. e. you CANNOT use normal RAM which 3335 will become available only after programming the 3336 memory controller and running certain initialization 3337 sequences. 3338 3339 U-Boot uses the following memory types: 3340 - MPC8xx: IMMR (internal memory of the CPU) 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 GENERATED_GBL_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_SCCR: System Clock and reset Control Register (15-27) 3361 3362- CONFIG_SYS_OR_TIMING_SDRAM: 3363 SDRAM timing 3364 3365- CONFIG_SYS_MAMR_PTA: 3366 periodic timer for refresh 3367 3368- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3369 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3370 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3371 CONFIG_SYS_BR1_PRELIM: 3372 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3373 3374- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3375 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3376 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3377 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3378 3379- CONFIG_PCI_ENUM_ONLY 3380 Only scan through and get the devices on the buses. 3381 Don't do any setup work, presumably because someone or 3382 something has already done it, and we don't need to do it 3383 a second time. Useful for platforms that are pre-booted 3384 by coreboot or similar. 3385 3386- CONFIG_PCI_INDIRECT_BRIDGE: 3387 Enable support for indirect PCI bridges. 3388 3389- CONFIG_SYS_SRIO: 3390 Chip has SRIO or not 3391 3392- CONFIG_SRIO1: 3393 Board has SRIO 1 port available 3394 3395- CONFIG_SRIO2: 3396 Board has SRIO 2 port available 3397 3398- CONFIG_SRIO_PCIE_BOOT_MASTER 3399 Board can support master function for Boot from SRIO and PCIE 3400 3401- CONFIG_SYS_SRIOn_MEM_VIRT: 3402 Virtual Address of SRIO port 'n' memory region 3403 3404- CONFIG_SYS_SRIOn_MEM_PHYS: 3405 Physical Address of SRIO port 'n' memory region 3406 3407- CONFIG_SYS_SRIOn_MEM_SIZE: 3408 Size of SRIO port 'n' memory region 3409 3410- CONFIG_SYS_NAND_BUSWIDTH_16BIT 3411 Defined to tell the NAND controller that the NAND chip is using 3412 a 16 bit bus. 3413 Not all NAND drivers use this symbol. 3414 Example of drivers that use it: 3415 - drivers/mtd/nand/ndfc.c 3416 - drivers/mtd/nand/mxc_nand.c 3417 3418- CONFIG_SYS_NDFC_EBC0_CFG 3419 Sets the EBC0_CFG register for the NDFC. If not defined 3420 a default value will be used. 3421 3422- CONFIG_SPD_EEPROM 3423 Get DDR timing information from an I2C EEPROM. Common 3424 with pluggable memory modules such as SODIMMs 3425 3426 SPD_EEPROM_ADDRESS 3427 I2C address of the SPD EEPROM 3428 3429- CONFIG_SYS_SPD_BUS_NUM 3430 If SPD EEPROM is on an I2C bus other than the first 3431 one, specify here. Note that the value must resolve 3432 to something your driver can deal with. 3433 3434- CONFIG_SYS_DDR_RAW_TIMING 3435 Get DDR timing information from other than SPD. Common with 3436 soldered DDR chips onboard without SPD. DDR raw timing 3437 parameters are extracted from datasheet and hard-coded into 3438 header files or board specific files. 3439 3440- CONFIG_FSL_DDR_INTERACTIVE 3441 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3442 3443- CONFIG_FSL_DDR_SYNC_REFRESH 3444 Enable sync of refresh for multiple controllers. 3445 3446- CONFIG_FSL_DDR_BIST 3447 Enable built-in memory test for Freescale DDR controllers. 3448 3449- CONFIG_SYS_83XX_DDR_USES_CS0 3450 Only for 83xx systems. If specified, then DDR should 3451 be configured using CS0 and CS1 instead of CS2 and CS3. 3452 3453- CONFIG_RMII 3454 Enable RMII mode for all FECs. 3455 Note that this is a global option, we can't 3456 have one FEC in standard MII mode and another in RMII mode. 3457 3458- CONFIG_CRC32_VERIFY 3459 Add a verify option to the crc32 command. 3460 The syntax is: 3461 3462 => crc32 -v <address> <count> <crc32> 3463 3464 Where address/count indicate a memory area 3465 and crc32 is the correct crc32 which the 3466 area should have. 3467 3468- CONFIG_LOOPW 3469 Add the "loopw" memory command. This only takes effect if 3470 the memory commands are activated globally (CONFIG_CMD_MEMORY). 3471 3472- CONFIG_MX_CYCLIC 3473 Add the "mdc" and "mwc" memory commands. These are cyclic 3474 "md/mw" commands. 3475 Examples: 3476 3477 => mdc.b 10 4 500 3478 This command will print 4 bytes (10,11,12,13) each 500 ms. 3479 3480 => mwc.l 100 12345678 10 3481 This command will write 12345678 to address 100 all 10 ms. 3482 3483 This only takes effect if the memory commands are activated 3484 globally (CONFIG_CMD_MEMORY). 3485 3486- CONFIG_SKIP_LOWLEVEL_INIT 3487 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain 3488 low level initializations (like setting up the memory 3489 controller) are omitted and/or U-Boot does not 3490 relocate itself into RAM. 3491 3492 Normally this variable MUST NOT be defined. The only 3493 exception is when U-Boot is loaded (to RAM) by some 3494 other boot loader or by a debugger which performs 3495 these initializations itself. 3496 3497- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 3498 [ARM926EJ-S only] This allows just the call to lowlevel_init() 3499 to be skipped. The normal CP15 init (such as enabling the 3500 instruction cache) is still performed. 3501 3502- CONFIG_SPL_BUILD 3503 Modifies the behaviour of start.S when compiling a loader 3504 that is executed before the actual U-Boot. E.g. when 3505 compiling a NAND SPL. 3506 3507- CONFIG_TPL_BUILD 3508 Modifies the behaviour of start.S when compiling a loader 3509 that is executed after the SPL and before the actual U-Boot. 3510 It is loaded by the SPL. 3511 3512- CONFIG_SYS_MPC85XX_NO_RESETVEC 3513 Only for 85xx systems. If this variable is specified, the section 3514 .resetvec is not kept and the section .bootpg is placed in the 3515 previous 4k of the .text section. 3516 3517- CONFIG_ARCH_MAP_SYSMEM 3518 Generally U-Boot (and in particular the md command) uses 3519 effective address. It is therefore not necessary to regard 3520 U-Boot address as virtual addresses that need to be translated 3521 to physical addresses. However, sandbox requires this, since 3522 it maintains its own little RAM buffer which contains all 3523 addressable memory. This option causes some memory accesses 3524 to be mapped through map_sysmem() / unmap_sysmem(). 3525 3526- CONFIG_X86_RESET_VECTOR 3527 If defined, the x86 reset vector code is included. This is not 3528 needed when U-Boot is running from Coreboot. 3529 3530- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 3531 Enables the RTC32K OSC on AM33xx based plattforms 3532 3533- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 3534 Option to disable subpage write in NAND driver 3535 driver that uses this: 3536 drivers/mtd/nand/davinci_nand.c 3537 3538Freescale QE/FMAN Firmware Support: 3539----------------------------------- 3540 3541The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 3542loading of "firmware", which is encoded in the QE firmware binary format. 3543This firmware often needs to be loaded during U-Boot booting, so macros 3544are used to identify the storage device (NOR flash, SPI, etc) and the address 3545within that device. 3546 3547- CONFIG_SYS_FMAN_FW_ADDR 3548 The address in the storage device where the FMAN microcode is located. The 3549 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3550 is also specified. 3551 3552- CONFIG_SYS_QE_FW_ADDR 3553 The address in the storage device where the QE microcode is located. The 3554 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3555 is also specified. 3556 3557- CONFIG_SYS_QE_FMAN_FW_LENGTH 3558 The maximum possible size of the firmware. The firmware binary format 3559 has a field that specifies the actual size of the firmware, but it 3560 might not be possible to read any part of the firmware unless some 3561 local storage is allocated to hold the entire firmware first. 3562 3563- CONFIG_SYS_QE_FMAN_FW_IN_NOR 3564 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 3565 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 3566 virtual address in NOR flash. 3567 3568- CONFIG_SYS_QE_FMAN_FW_IN_NAND 3569 Specifies that QE/FMAN firmware is located in NAND flash. 3570 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 3571 3572- CONFIG_SYS_QE_FMAN_FW_IN_MMC 3573 Specifies that QE/FMAN firmware is located on the primary SD/MMC 3574 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3575 3576- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 3577 Specifies that QE/FMAN firmware is located in the remote (master) 3578 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 3579 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 3580 window->master inbound window->master LAW->the ucode address in 3581 master's memory space. 3582 3583Freescale Layerscape Management Complex Firmware Support: 3584--------------------------------------------------------- 3585The Freescale Layerscape Management Complex (MC) supports the loading of 3586"firmware". 3587This firmware often needs to be loaded during U-Boot booting, so macros 3588are used to identify the storage device (NOR flash, SPI, etc) and the address 3589within that device. 3590 3591- CONFIG_FSL_MC_ENET 3592 Enable the MC driver for Layerscape SoCs. 3593 3594Freescale Layerscape Debug Server Support: 3595------------------------------------------- 3596The Freescale Layerscape Debug Server Support supports the loading of 3597"Debug Server firmware" and triggering SP boot-rom. 3598This firmware often needs to be loaded during U-Boot booting. 3599 3600- CONFIG_SYS_MC_RSV_MEM_ALIGN 3601 Define alignment of reserved memory MC requires 3602 3603Reproducible builds 3604------------------- 3605 3606In order to achieve reproducible builds, timestamps used in the U-Boot build 3607process have to be set to a fixed value. 3608 3609This is done using the SOURCE_DATE_EPOCH environment variable. 3610SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 3611option for U-Boot or an environment variable in U-Boot. 3612 3613SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 3614 3615Building the Software: 3616====================== 3617 3618Building U-Boot has been tested in several native build environments 3619and in many different cross environments. Of course we cannot support 3620all possibly existing versions of cross development tools in all 3621(potentially obsolete) versions. In case of tool chain problems we 3622recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3623which is extensively used to build and test U-Boot. 3624 3625If you are not using a native environment, it is assumed that you 3626have GNU cross compiling tools available in your path. In this case, 3627you must set the environment variable CROSS_COMPILE in your shell. 3628Note that no changes to the Makefile or any other source files are 3629necessary. For example using the ELDK on a 4xx CPU, please enter: 3630 3631 $ CROSS_COMPILE=ppc_4xx- 3632 $ export CROSS_COMPILE 3633 3634Note: If you wish to generate Windows versions of the utilities in 3635 the tools directory you can use the MinGW toolchain 3636 (http://www.mingw.org). Set your HOST tools to the MinGW 3637 toolchain and execute 'make tools'. For example: 3638 3639 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3640 3641 Binaries such as tools/mkimage.exe will be created which can 3642 be executed on computers running Windows. 3643 3644U-Boot is intended to be simple to build. After installing the 3645sources you must configure U-Boot for one specific board type. This 3646is done by typing: 3647 3648 make NAME_defconfig 3649 3650where "NAME_defconfig" is the name of one of the existing configu- 3651rations; see boards.cfg for supported names. 3652 3653Note: for some board special configuration names may exist; check if 3654 additional information is available from the board vendor; for 3655 instance, the TQM823L systems are available without (standard) 3656 or with LCD support. You can select such additional "features" 3657 when choosing the configuration, i. e. 3658 3659 make TQM823L_defconfig 3660 - will configure for a plain TQM823L, i. e. no LCD support 3661 3662 make TQM823L_LCD_defconfig 3663 - will configure for a TQM823L with U-Boot console on LCD 3664 3665 etc. 3666 3667 3668Finally, type "make all", and you should get some working U-Boot 3669images ready for download to / installation on your system: 3670 3671- "u-boot.bin" is a raw binary image 3672- "u-boot" is an image in ELF binary format 3673- "u-boot.srec" is in Motorola S-Record format 3674 3675By default the build is performed locally and the objects are saved 3676in the source directory. One of the two methods can be used to change 3677this behavior and build U-Boot to some external directory: 3678 36791. Add O= to the make command line invocations: 3680 3681 make O=/tmp/build distclean 3682 make O=/tmp/build NAME_defconfig 3683 make O=/tmp/build all 3684 36852. Set environment variable KBUILD_OUTPUT to point to the desired location: 3686 3687 export KBUILD_OUTPUT=/tmp/build 3688 make distclean 3689 make NAME_defconfig 3690 make all 3691 3692Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 3693variable. 3694 3695User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by 3696setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS. 3697For example to treat all compiler warnings as errors: 3698 3699 make KCFLAGS=-Werror 3700 3701Please be aware that the Makefiles assume you are using GNU make, so 3702for instance on NetBSD you might need to use "gmake" instead of 3703native "make". 3704 3705 3706If the system board that you have is not listed, then you will need 3707to port U-Boot to your hardware platform. To do this, follow these 3708steps: 3709 37101. Create a new directory to hold your board specific code. Add any 3711 files you need. In your board directory, you will need at least 3712 the "Makefile" and a "<board>.c". 37132. Create a new configuration file "include/configs/<board>.h" for 3714 your board. 37153. If you're porting U-Boot to a new CPU, then also create a new 3716 directory to hold your CPU specific code. Add any files you need. 37174. Run "make <board>_defconfig" with your new name. 37185. Type "make", and you should get a working "u-boot.srec" file 3719 to be installed on your target system. 37206. Debug and solve any problems that might arise. 3721 [Of course, this last step is much harder than it sounds.] 3722 3723 3724Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3725============================================================== 3726 3727If you have modified U-Boot sources (for instance added a new board 3728or support for new devices, a new CPU, etc.) you are expected to 3729provide feedback to the other developers. The feedback normally takes 3730the form of a "patch", i. e. a context diff against a certain (latest 3731official or latest in the git repository) version of U-Boot sources. 3732 3733But before you submit such a patch, please verify that your modifi- 3734cation did not break existing code. At least make sure that *ALL* of 3735the supported boards compile WITHOUT ANY compiler warnings. To do so, 3736just run the buildman script (tools/buildman/buildman), which will 3737configure and build U-Boot for ALL supported system. Be warned, this 3738will take a while. Please see the buildman README, or run 'buildman -H' 3739for documentation. 3740 3741 3742See also "U-Boot Porting Guide" below. 3743 3744 3745Monitor Commands - Overview: 3746============================ 3747 3748go - start application at address 'addr' 3749run - run commands in an environment variable 3750bootm - boot application image from memory 3751bootp - boot image via network using BootP/TFTP protocol 3752bootz - boot zImage from memory 3753tftpboot- boot image via network using TFTP protocol 3754 and env variables "ipaddr" and "serverip" 3755 (and eventually "gatewayip") 3756tftpput - upload a file via network using TFTP protocol 3757rarpboot- boot image via network using RARP/TFTP protocol 3758diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 3759loads - load S-Record file over serial line 3760loadb - load binary file over serial line (kermit mode) 3761md - memory display 3762mm - memory modify (auto-incrementing) 3763nm - memory modify (constant address) 3764mw - memory write (fill) 3765cp - memory copy 3766cmp - memory compare 3767crc32 - checksum calculation 3768i2c - I2C sub-system 3769sspi - SPI utility commands 3770base - print or set address offset 3771printenv- print environment variables 3772setenv - set environment variables 3773saveenv - save environment variables to persistent storage 3774protect - enable or disable FLASH write protection 3775erase - erase FLASH memory 3776flinfo - print FLASH memory information 3777nand - NAND memory operations (see doc/README.nand) 3778bdinfo - print Board Info structure 3779iminfo - print header information for application image 3780coninfo - print console devices and informations 3781ide - IDE sub-system 3782loop - infinite loop on address range 3783loopw - infinite write loop on address range 3784mtest - simple RAM test 3785icache - enable or disable instruction cache 3786dcache - enable or disable data cache 3787reset - Perform RESET of the CPU 3788echo - echo args to console 3789version - print monitor version 3790help - print online help 3791? - alias for 'help' 3792 3793 3794Monitor Commands - Detailed Description: 3795======================================== 3796 3797TODO. 3798 3799For now: just type "help <command>". 3800 3801 3802Environment Variables: 3803====================== 3804 3805U-Boot supports user configuration using Environment Variables which 3806can be made persistent by saving to Flash memory. 3807 3808Environment Variables are set using "setenv", printed using 3809"printenv", and saved to Flash using "saveenv". Using "setenv" 3810without a value can be used to delete a variable from the 3811environment. As long as you don't save the environment you are 3812working with an in-memory copy. In case the Flash area containing the 3813environment is erased by accident, a default environment is provided. 3814 3815Some configuration options can be set using Environment Variables. 3816 3817List of environment variables (most likely not complete): 3818 3819 baudrate - see CONFIG_BAUDRATE 3820 3821 bootdelay - see CONFIG_BOOTDELAY 3822 3823 bootcmd - see CONFIG_BOOTCOMMAND 3824 3825 bootargs - Boot arguments when booting an RTOS image 3826 3827 bootfile - Name of the image to load with TFTP 3828 3829 bootm_low - Memory range available for image processing in the bootm 3830 command can be restricted. This variable is given as 3831 a hexadecimal number and defines lowest address allowed 3832 for use by the bootm command. See also "bootm_size" 3833 environment variable. Address defined by "bootm_low" is 3834 also the base of the initial memory mapping for the Linux 3835 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 3836 bootm_mapsize. 3837 3838 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 3839 This variable is given as a hexadecimal number and it 3840 defines the size of the memory region starting at base 3841 address bootm_low that is accessible by the Linux kernel 3842 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 3843 as the default value if it is defined, and bootm_size is 3844 used otherwise. 3845 3846 bootm_size - Memory range available for image processing in the bootm 3847 command can be restricted. This variable is given as 3848 a hexadecimal number and defines the size of the region 3849 allowed for use by the bootm command. See also "bootm_low" 3850 environment variable. 3851 3852 updatefile - Location of the software update file on a TFTP server, used 3853 by the automatic software update feature. Please refer to 3854 documentation in doc/README.update for more details. 3855 3856 autoload - if set to "no" (any string beginning with 'n'), 3857 "bootp" will just load perform a lookup of the 3858 configuration from the BOOTP server, but not try to 3859 load any image using TFTP 3860 3861 autostart - if set to "yes", an image loaded using the "bootp", 3862 "rarpboot", "tftpboot" or "diskboot" commands will 3863 be automatically started (by internally calling 3864 "bootm") 3865 3866 If set to "no", a standalone image passed to the 3867 "bootm" command will be copied to the load address 3868 (and eventually uncompressed), but NOT be started. 3869 This can be used to load and uncompress arbitrary 3870 data. 3871 3872 fdt_high - if set this restricts the maximum address that the 3873 flattened device tree will be copied into upon boot. 3874 For example, if you have a system with 1 GB memory 3875 at physical address 0x10000000, while Linux kernel 3876 only recognizes the first 704 MB as low memory, you 3877 may need to set fdt_high as 0x3C000000 to have the 3878 device tree blob be copied to the maximum address 3879 of the 704 MB low memory, so that Linux kernel can 3880 access it during the boot procedure. 3881 3882 If this is set to the special value 0xFFFFFFFF then 3883 the fdt will not be copied at all on boot. For this 3884 to work it must reside in writable memory, have 3885 sufficient padding on the end of it for u-boot to 3886 add the information it needs into it, and the memory 3887 must be accessible by the kernel. 3888 3889 fdtcontroladdr- if set this is the address of the control flattened 3890 device tree used by U-Boot when CONFIG_OF_CONTROL is 3891 defined. 3892 3893 i2cfast - (PPC405GP|PPC405EP only) 3894 if set to 'y' configures Linux I2C driver for fast 3895 mode (400kHZ). This environment variable is used in 3896 initialization code. So, for changes to be effective 3897 it must be saved and board must be reset. 3898 3899 initrd_high - restrict positioning of initrd images: 3900 If this variable is not set, initrd images will be 3901 copied to the highest possible address in RAM; this 3902 is usually what you want since it allows for 3903 maximum initrd size. If for some reason you want to 3904 make sure that the initrd image is loaded below the 3905 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 3906 variable to a value of "no" or "off" or "0". 3907 Alternatively, you can set it to a maximum upper 3908 address to use (U-Boot will still check that it 3909 does not overwrite the U-Boot stack and data). 3910 3911 For instance, when you have a system with 16 MB 3912 RAM, and want to reserve 4 MB from use by Linux, 3913 you can do this by adding "mem=12M" to the value of 3914 the "bootargs" variable. However, now you must make 3915 sure that the initrd image is placed in the first 3916 12 MB as well - this can be done with 3917 3918 setenv initrd_high 00c00000 3919 3920 If you set initrd_high to 0xFFFFFFFF, this is an 3921 indication to U-Boot that all addresses are legal 3922 for the Linux kernel, including addresses in flash 3923 memory. In this case U-Boot will NOT COPY the 3924 ramdisk at all. This may be useful to reduce the 3925 boot time on your system, but requires that this 3926 feature is supported by your Linux kernel. 3927 3928 ipaddr - IP address; needed for tftpboot command 3929 3930 loadaddr - Default load address for commands like "bootp", 3931 "rarpboot", "tftpboot", "loadb" or "diskboot" 3932 3933 loads_echo - see CONFIG_LOADS_ECHO 3934 3935 serverip - TFTP server IP address; needed for tftpboot command 3936 3937 bootretry - see CONFIG_BOOT_RETRY_TIME 3938 3939 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 3940 3941 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 3942 3943 ethprime - controls which interface is used first. 3944 3945 ethact - controls which interface is currently active. 3946 For example you can do the following 3947 3948 => setenv ethact FEC 3949 => ping 192.168.0.1 # traffic sent on FEC 3950 => setenv ethact SCC 3951 => ping 10.0.0.1 # traffic sent on SCC 3952 3953 ethrotate - When set to "no" U-Boot does not go through all 3954 available network interfaces. 3955 It just stays at the currently selected interface. 3956 3957 netretry - When set to "no" each network operation will 3958 either succeed or fail without retrying. 3959 When set to "once" the network operation will 3960 fail when all the available network interfaces 3961 are tried once without success. 3962 Useful on scripts which control the retry operation 3963 themselves. 3964 3965 npe_ucode - set load address for the NPE microcode 3966 3967 silent_linux - If set then Linux will be told to boot silently, by 3968 changing the console to be empty. If "yes" it will be 3969 made silent. If "no" it will not be made silent. If 3970 unset, then it will be made silent if the U-Boot console 3971 is silent. 3972 3973 tftpsrcp - If this is set, the value is used for TFTP's 3974 UDP source port. 3975 3976 tftpdstp - If this is set, the value is used for TFTP's UDP 3977 destination port instead of the Well Know Port 69. 3978 3979 tftpblocksize - Block size to use for TFTP transfers; if not set, 3980 we use the TFTP server's default block size 3981 3982 tftptimeout - Retransmission timeout for TFTP packets (in milli- 3983 seconds, minimum value is 1000 = 1 second). Defines 3984 when a packet is considered to be lost so it has to 3985 be retransmitted. The default is 5000 = 5 seconds. 3986 Lowering this value may make downloads succeed 3987 faster in networks with high packet loss rates or 3988 with unreliable TFTP servers. 3989 3990 tftptimeoutcountmax - maximum count of TFTP timeouts (no 3991 unit, minimum value = 0). Defines how many timeouts 3992 can happen during a single file transfer before that 3993 transfer is aborted. The default is 10, and 0 means 3994 'no timeouts allowed'. Increasing this value may help 3995 downloads succeed with high packet loss rates, or with 3996 unreliable TFTP servers or client hardware. 3997 3998 vlan - When set to a value < 4095 the traffic over 3999 Ethernet is encapsulated/received over 802.1q 4000 VLAN tagged frames. 4001 4002 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 4003 Unsigned value, in milliseconds. If not set, the period will 4004 be either the default (28000), or a value based on 4005 CONFIG_NET_RETRY_COUNT, if defined. This value has 4006 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 4007 4008The following image location variables contain the location of images 4009used in booting. The "Image" column gives the role of the image and is 4010not an environment variable name. The other columns are environment 4011variable names. "File Name" gives the name of the file on a TFTP 4012server, "RAM Address" gives the location in RAM the image will be 4013loaded to, and "Flash Location" gives the image's address in NOR 4014flash or offset in NAND flash. 4015 4016*Note* - these variables don't have to be defined for all boards, some 4017boards currently use other variables for these purposes, and some 4018boards use these variables for other purposes. 4019 4020Image File Name RAM Address Flash Location 4021----- --------- ----------- -------------- 4022u-boot u-boot u-boot_addr_r u-boot_addr 4023Linux kernel bootfile kernel_addr_r kernel_addr 4024device tree blob fdtfile fdt_addr_r fdt_addr 4025ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4026 4027The following environment variables may be used and automatically 4028updated by the network boot commands ("bootp" and "rarpboot"), 4029depending the information provided by your boot server: 4030 4031 bootfile - see above 4032 dnsip - IP address of your Domain Name Server 4033 dnsip2 - IP address of your secondary Domain Name Server 4034 gatewayip - IP address of the Gateway (Router) to use 4035 hostname - Target hostname 4036 ipaddr - see above 4037 netmask - Subnet Mask 4038 rootpath - Pathname of the root filesystem on the NFS server 4039 serverip - see above 4040 4041 4042There are two special Environment Variables: 4043 4044 serial# - contains hardware identification information such 4045 as type string and/or serial number 4046 ethaddr - Ethernet address 4047 4048These variables can be set only once (usually during manufacturing of 4049the board). U-Boot refuses to delete or overwrite these variables 4050once they have been set once. 4051 4052 4053Further special Environment Variables: 4054 4055 ver - Contains the U-Boot version string as printed 4056 with the "version" command. This variable is 4057 readonly (see CONFIG_VERSION_VARIABLE). 4058 4059 4060Please note that changes to some configuration parameters may take 4061only effect after the next boot (yes, that's just like Windoze :-). 4062 4063 4064Callback functions for environment variables: 4065--------------------------------------------- 4066 4067For some environment variables, the behavior of u-boot needs to change 4068when their values are changed. This functionality allows functions to 4069be associated with arbitrary variables. On creation, overwrite, or 4070deletion, the callback will provide the opportunity for some side 4071effect to happen or for the change to be rejected. 4072 4073The callbacks are named and associated with a function using the 4074U_BOOT_ENV_CALLBACK macro in your board or driver code. 4075 4076These callbacks are associated with variables in one of two ways. The 4077static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4078in the board configuration to a string that defines a list of 4079associations. The list must be in the following format: 4080 4081 entry = variable_name[:callback_name] 4082 list = entry[,list] 4083 4084If the callback name is not specified, then the callback is deleted. 4085Spaces are also allowed anywhere in the list. 4086 4087Callbacks can also be associated by defining the ".callbacks" variable 4088with the same list format above. Any association in ".callbacks" will 4089override any association in the static list. You can define 4090CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4091".callbacks" environment variable in the default or embedded environment. 4092 4093If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4094regular expression. This allows multiple variables to be connected to 4095the same callback without explicitly listing them all out. 4096 4097 4098Command Line Parsing: 4099===================== 4100 4101There are two different command line parsers available with U-Boot: 4102the old "simple" one, and the much more powerful "hush" shell: 4103 4104Old, simple command line parser: 4105-------------------------------- 4106 4107- supports environment variables (through setenv / saveenv commands) 4108- several commands on one line, separated by ';' 4109- variable substitution using "... ${name} ..." syntax 4110- special characters ('$', ';') can be escaped by prefixing with '\', 4111 for example: 4112 setenv bootcmd bootm \${address} 4113- You can also escape text by enclosing in single apostrophes, for example: 4114 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4115 4116Hush shell: 4117----------- 4118 4119- similar to Bourne shell, with control structures like 4120 if...then...else...fi, for...do...done; while...do...done, 4121 until...do...done, ... 4122- supports environment ("global") variables (through setenv / saveenv 4123 commands) and local shell variables (through standard shell syntax 4124 "name=value"); only environment variables can be used with "run" 4125 command 4126 4127General rules: 4128-------------- 4129 4130(1) If a command line (or an environment variable executed by a "run" 4131 command) contains several commands separated by semicolon, and 4132 one of these commands fails, then the remaining commands will be 4133 executed anyway. 4134 4135(2) If you execute several variables with one call to run (i. e. 4136 calling run with a list of variables as arguments), any failing 4137 command will cause "run" to terminate, i. e. the remaining 4138 variables are not executed. 4139 4140Note for Redundant Ethernet Interfaces: 4141======================================= 4142 4143Some boards come with redundant Ethernet interfaces; U-Boot supports 4144such configurations and is capable of automatic selection of a 4145"working" interface when needed. MAC assignment works as follows: 4146 4147Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 4148MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 4149"eth1addr" (=>eth1), "eth2addr", ... 4150 4151If the network interface stores some valid MAC address (for instance 4152in SROM), this is used as default address if there is NO correspon- 4153ding setting in the environment; if the corresponding environment 4154variable is set, this overrides the settings in the card; that means: 4155 4156o If the SROM has a valid MAC address, and there is no address in the 4157 environment, the SROM's address is used. 4158 4159o If there is no valid address in the SROM, and a definition in the 4160 environment exists, then the value from the environment variable is 4161 used. 4162 4163o If both the SROM and the environment contain a MAC address, and 4164 both addresses are the same, this MAC address is used. 4165 4166o If both the SROM and the environment contain a MAC address, and the 4167 addresses differ, the value from the environment is used and a 4168 warning is printed. 4169 4170o If neither SROM nor the environment contain a MAC address, an error 4171 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 4172 a random, locally-assigned MAC is used. 4173 4174If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 4175will be programmed into hardware as part of the initialization process. This 4176may be skipped by setting the appropriate 'ethmacskip' environment variable. 4177The naming convention is as follows: 4178"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 4179 4180Image Formats: 4181============== 4182 4183U-Boot is capable of booting (and performing other auxiliary operations on) 4184images in two formats: 4185 4186New uImage format (FIT) 4187----------------------- 4188 4189Flexible and powerful format based on Flattened Image Tree -- FIT (similar 4190to Flattened Device Tree). It allows the use of images with multiple 4191components (several kernels, ramdisks, etc.), with contents protected by 4192SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 4193 4194 4195Old uImage format 4196----------------- 4197 4198Old image format is based on binary files which can be basically anything, 4199preceded by a special header; see the definitions in include/image.h for 4200details; basically, the header defines the following image properties: 4201 4202* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 4203 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 4204 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 4205 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 4206 INTEGRITY). 4207* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86, 4208 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 4209 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC). 4210* Compression Type (uncompressed, gzip, bzip2) 4211* Load Address 4212* Entry Point 4213* Image Name 4214* Image Timestamp 4215 4216The header is marked by a special Magic Number, and both the header 4217and the data portions of the image are secured against corruption by 4218CRC32 checksums. 4219 4220 4221Linux Support: 4222============== 4223 4224Although U-Boot should support any OS or standalone application 4225easily, the main focus has always been on Linux during the design of 4226U-Boot. 4227 4228U-Boot includes many features that so far have been part of some 4229special "boot loader" code within the Linux kernel. Also, any 4230"initrd" images to be used are no longer part of one big Linux image; 4231instead, kernel and "initrd" are separate images. This implementation 4232serves several purposes: 4233 4234- the same features can be used for other OS or standalone 4235 applications (for instance: using compressed images to reduce the 4236 Flash memory footprint) 4237 4238- it becomes much easier to port new Linux kernel versions because 4239 lots of low-level, hardware dependent stuff are done by U-Boot 4240 4241- the same Linux kernel image can now be used with different "initrd" 4242 images; of course this also means that different kernel images can 4243 be run with the same "initrd". This makes testing easier (you don't 4244 have to build a new "zImage.initrd" Linux image when you just 4245 change a file in your "initrd"). Also, a field-upgrade of the 4246 software is easier now. 4247 4248 4249Linux HOWTO: 4250============ 4251 4252Porting Linux to U-Boot based systems: 4253--------------------------------------- 4254 4255U-Boot cannot save you from doing all the necessary modifications to 4256configure the Linux device drivers for use with your target hardware 4257(no, we don't intend to provide a full virtual machine interface to 4258Linux :-). 4259 4260But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 4261 4262Just make sure your machine specific header file (for instance 4263include/asm-ppc/tqm8xx.h) includes the same definition of the Board 4264Information structure as we define in include/asm-<arch>/u-boot.h, 4265and make sure that your definition of IMAP_ADDR uses the same value 4266as your U-Boot configuration in CONFIG_SYS_IMMR. 4267 4268Note that U-Boot now has a driver model, a unified model for drivers. 4269If you are adding a new driver, plumb it into driver model. If there 4270is no uclass available, you are encouraged to create one. See 4271doc/driver-model. 4272 4273 4274Configuring the Linux kernel: 4275----------------------------- 4276 4277No specific requirements for U-Boot. Make sure you have some root 4278device (initial ramdisk, NFS) for your target system. 4279 4280 4281Building a Linux Image: 4282----------------------- 4283 4284With U-Boot, "normal" build targets like "zImage" or "bzImage" are 4285not used. If you use recent kernel source, a new build target 4286"uImage" will exist which automatically builds an image usable by 4287U-Boot. Most older kernels also have support for a "pImage" target, 4288which was introduced for our predecessor project PPCBoot and uses a 4289100% compatible format. 4290 4291Example: 4292 4293 make TQM850L_defconfig 4294 make oldconfig 4295 make dep 4296 make uImage 4297 4298The "uImage" build target uses a special tool (in 'tools/mkimage') to 4299encapsulate a compressed Linux kernel image with header information, 4300CRC32 checksum etc. for use with U-Boot. This is what we are doing: 4301 4302* build a standard "vmlinux" kernel image (in ELF binary format): 4303 4304* convert the kernel into a raw binary image: 4305 4306 ${CROSS_COMPILE}-objcopy -O binary \ 4307 -R .note -R .comment \ 4308 -S vmlinux linux.bin 4309 4310* compress the binary image: 4311 4312 gzip -9 linux.bin 4313 4314* package compressed binary image for U-Boot: 4315 4316 mkimage -A ppc -O linux -T kernel -C gzip \ 4317 -a 0 -e 0 -n "Linux Kernel Image" \ 4318 -d linux.bin.gz uImage 4319 4320 4321The "mkimage" tool can also be used to create ramdisk images for use 4322with U-Boot, either separated from the Linux kernel image, or 4323combined into one file. "mkimage" encapsulates the images with a 64 4324byte header containing information about target architecture, 4325operating system, image type, compression method, entry points, time 4326stamp, CRC32 checksums, etc. 4327 4328"mkimage" can be called in two ways: to verify existing images and 4329print the header information, or to build new images. 4330 4331In the first form (with "-l" option) mkimage lists the information 4332contained in the header of an existing U-Boot image; this includes 4333checksum verification: 4334 4335 tools/mkimage -l image 4336 -l ==> list image header information 4337 4338The second form (with "-d" option) is used to build a U-Boot image 4339from a "data file" which is used as image payload: 4340 4341 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 4342 -n name -d data_file image 4343 -A ==> set architecture to 'arch' 4344 -O ==> set operating system to 'os' 4345 -T ==> set image type to 'type' 4346 -C ==> set compression type 'comp' 4347 -a ==> set load address to 'addr' (hex) 4348 -e ==> set entry point to 'ep' (hex) 4349 -n ==> set image name to 'name' 4350 -d ==> use image data from 'datafile' 4351 4352Right now, all Linux kernels for PowerPC systems use the same load 4353address (0x00000000), but the entry point address depends on the 4354kernel version: 4355 4356- 2.2.x kernels have the entry point at 0x0000000C, 4357- 2.3.x and later kernels have the entry point at 0x00000000. 4358 4359So a typical call to build a U-Boot image would read: 4360 4361 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4362 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 4363 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 4364 > examples/uImage.TQM850L 4365 Image Name: 2.4.4 kernel for TQM850L 4366 Created: Wed Jul 19 02:34:59 2000 4367 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4368 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4369 Load Address: 0x00000000 4370 Entry Point: 0x00000000 4371 4372To verify the contents of the image (or check for corruption): 4373 4374 -> tools/mkimage -l examples/uImage.TQM850L 4375 Image Name: 2.4.4 kernel for TQM850L 4376 Created: Wed Jul 19 02:34:59 2000 4377 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4378 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4379 Load Address: 0x00000000 4380 Entry Point: 0x00000000 4381 4382NOTE: for embedded systems where boot time is critical you can trade 4383speed for memory and install an UNCOMPRESSED image instead: this 4384needs more space in Flash, but boots much faster since it does not 4385need to be uncompressed: 4386 4387 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 4388 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4389 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 4390 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 4391 > examples/uImage.TQM850L-uncompressed 4392 Image Name: 2.4.4 kernel for TQM850L 4393 Created: Wed Jul 19 02:34:59 2000 4394 Image Type: PowerPC Linux Kernel Image (uncompressed) 4395 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 4396 Load Address: 0x00000000 4397 Entry Point: 0x00000000 4398 4399 4400Similar you can build U-Boot images from a 'ramdisk.image.gz' file 4401when your kernel is intended to use an initial ramdisk: 4402 4403 -> tools/mkimage -n 'Simple Ramdisk Image' \ 4404 > -A ppc -O linux -T ramdisk -C gzip \ 4405 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 4406 Image Name: Simple Ramdisk Image 4407 Created: Wed Jan 12 14:01:50 2000 4408 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4409 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 4410 Load Address: 0x00000000 4411 Entry Point: 0x00000000 4412 4413The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 4414option performs the converse operation of the mkimage's second form (the "-d" 4415option). Given an image built by mkimage, the dumpimage extracts a "data file" 4416from the image: 4417 4418 tools/dumpimage -i image -T type -p position data_file 4419 -i ==> extract from the 'image' a specific 'data_file' 4420 -T ==> set image type to 'type' 4421 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 4422 4423 4424Installing a Linux Image: 4425------------------------- 4426 4427To downloading a U-Boot image over the serial (console) interface, 4428you must convert the image to S-Record format: 4429 4430 objcopy -I binary -O srec examples/image examples/image.srec 4431 4432The 'objcopy' does not understand the information in the U-Boot 4433image header, so the resulting S-Record file will be relative to 4434address 0x00000000. To load it to a given address, you need to 4435specify the target address as 'offset' parameter with the 'loads' 4436command. 4437 4438Example: install the image to address 0x40100000 (which on the 4439TQM8xxL is in the first Flash bank): 4440 4441 => erase 40100000 401FFFFF 4442 4443 .......... done 4444 Erased 8 sectors 4445 4446 => loads 40100000 4447 ## Ready for S-Record download ... 4448 ~>examples/image.srec 4449 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 4450 ... 4451 15989 15990 15991 15992 4452 [file transfer complete] 4453 [connected] 4454 ## Start Addr = 0x00000000 4455 4456 4457You can check the success of the download using the 'iminfo' command; 4458this includes a checksum verification so you can be sure no data 4459corruption happened: 4460 4461 => imi 40100000 4462 4463 ## Checking Image at 40100000 ... 4464 Image Name: 2.2.13 for initrd on TQM850L 4465 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4466 Data Size: 335725 Bytes = 327 kB = 0 MB 4467 Load Address: 00000000 4468 Entry Point: 0000000c 4469 Verifying Checksum ... OK 4470 4471 4472Boot Linux: 4473----------- 4474 4475The "bootm" command is used to boot an application that is stored in 4476memory (RAM or Flash). In case of a Linux kernel image, the contents 4477of the "bootargs" environment variable is passed to the kernel as 4478parameters. You can check and modify this variable using the 4479"printenv" and "setenv" commands: 4480 4481 4482 => printenv bootargs 4483 bootargs=root=/dev/ram 4484 4485 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4486 4487 => printenv bootargs 4488 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4489 4490 => bootm 40020000 4491 ## Booting Linux kernel at 40020000 ... 4492 Image Name: 2.2.13 for NFS on TQM850L 4493 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4494 Data Size: 381681 Bytes = 372 kB = 0 MB 4495 Load Address: 00000000 4496 Entry Point: 0000000c 4497 Verifying Checksum ... OK 4498 Uncompressing Kernel Image ... OK 4499 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 4500 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4501 time_init: decrementer frequency = 187500000/60 4502 Calibrating delay loop... 49.77 BogoMIPS 4503 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4504 ... 4505 4506If you want to boot a Linux kernel with initial RAM disk, you pass 4507the memory addresses of both the kernel and the initrd image (PPBCOOT 4508format!) to the "bootm" command: 4509 4510 => imi 40100000 40200000 4511 4512 ## Checking Image at 40100000 ... 4513 Image Name: 2.2.13 for initrd on TQM850L 4514 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4515 Data Size: 335725 Bytes = 327 kB = 0 MB 4516 Load Address: 00000000 4517 Entry Point: 0000000c 4518 Verifying Checksum ... OK 4519 4520 ## Checking Image at 40200000 ... 4521 Image Name: Simple Ramdisk Image 4522 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4523 Data Size: 566530 Bytes = 553 kB = 0 MB 4524 Load Address: 00000000 4525 Entry Point: 00000000 4526 Verifying Checksum ... OK 4527 4528 => bootm 40100000 40200000 4529 ## Booting Linux kernel at 40100000 ... 4530 Image Name: 2.2.13 for initrd on TQM850L 4531 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4532 Data Size: 335725 Bytes = 327 kB = 0 MB 4533 Load Address: 00000000 4534 Entry Point: 0000000c 4535 Verifying Checksum ... OK 4536 Uncompressing Kernel Image ... OK 4537 ## Loading RAMDisk Image at 40200000 ... 4538 Image Name: Simple Ramdisk Image 4539 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4540 Data Size: 566530 Bytes = 553 kB = 0 MB 4541 Load Address: 00000000 4542 Entry Point: 00000000 4543 Verifying Checksum ... OK 4544 Loading Ramdisk ... OK 4545 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 4546 Boot arguments: root=/dev/ram 4547 time_init: decrementer frequency = 187500000/60 4548 Calibrating delay loop... 49.77 BogoMIPS 4549 ... 4550 RAMDISK: Compressed image found at block 0 4551 VFS: Mounted root (ext2 filesystem). 4552 4553 bash# 4554 4555Boot Linux and pass a flat device tree: 4556----------- 4557 4558First, U-Boot must be compiled with the appropriate defines. See the section 4559titled "Linux Kernel Interface" above for a more in depth explanation. The 4560following is an example of how to start a kernel and pass an updated 4561flat device tree: 4562 4563=> print oftaddr 4564oftaddr=0x300000 4565=> print oft 4566oft=oftrees/mpc8540ads.dtb 4567=> tftp $oftaddr $oft 4568Speed: 1000, full duplex 4569Using TSEC0 device 4570TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4571Filename 'oftrees/mpc8540ads.dtb'. 4572Load address: 0x300000 4573Loading: # 4574done 4575Bytes transferred = 4106 (100a hex) 4576=> tftp $loadaddr $bootfile 4577Speed: 1000, full duplex 4578Using TSEC0 device 4579TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4580Filename 'uImage'. 4581Load address: 0x200000 4582Loading:############ 4583done 4584Bytes transferred = 1029407 (fb51f hex) 4585=> print loadaddr 4586loadaddr=200000 4587=> print oftaddr 4588oftaddr=0x300000 4589=> bootm $loadaddr - $oftaddr 4590## Booting image at 00200000 ... 4591 Image Name: Linux-2.6.17-dirty 4592 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4593 Data Size: 1029343 Bytes = 1005.2 kB 4594 Load Address: 00000000 4595 Entry Point: 00000000 4596 Verifying Checksum ... OK 4597 Uncompressing Kernel Image ... OK 4598Booting using flat device tree at 0x300000 4599Using MPC85xx ADS machine description 4600Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4601[snip] 4602 4603 4604More About U-Boot Image Types: 4605------------------------------ 4606 4607U-Boot supports the following image types: 4608 4609 "Standalone Programs" are directly runnable in the environment 4610 provided by U-Boot; it is expected that (if they behave 4611 well) you can continue to work in U-Boot after return from 4612 the Standalone Program. 4613 "OS Kernel Images" are usually images of some Embedded OS which 4614 will take over control completely. Usually these programs 4615 will install their own set of exception handlers, device 4616 drivers, set up the MMU, etc. - this means, that you cannot 4617 expect to re-enter U-Boot except by resetting the CPU. 4618 "RAMDisk Images" are more or less just data blocks, and their 4619 parameters (address, size) are passed to an OS kernel that is 4620 being started. 4621 "Multi-File Images" contain several images, typically an OS 4622 (Linux) kernel image and one or more data images like 4623 RAMDisks. This construct is useful for instance when you want 4624 to boot over the network using BOOTP etc., where the boot 4625 server provides just a single image file, but you want to get 4626 for instance an OS kernel and a RAMDisk image. 4627 4628 "Multi-File Images" start with a list of image sizes, each 4629 image size (in bytes) specified by an "uint32_t" in network 4630 byte order. This list is terminated by an "(uint32_t)0". 4631 Immediately after the terminating 0 follow the images, one by 4632 one, all aligned on "uint32_t" boundaries (size rounded up to 4633 a multiple of 4 bytes). 4634 4635 "Firmware Images" are binary images containing firmware (like 4636 U-Boot or FPGA images) which usually will be programmed to 4637 flash memory. 4638 4639 "Script files" are command sequences that will be executed by 4640 U-Boot's command interpreter; this feature is especially 4641 useful when you configure U-Boot to use a real shell (hush) 4642 as command interpreter. 4643 4644Booting the Linux zImage: 4645------------------------- 4646 4647On some platforms, it's possible to boot Linux zImage. This is done 4648using the "bootz" command. The syntax of "bootz" command is the same 4649as the syntax of "bootm" command. 4650 4651Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 4652kernel with raw initrd images. The syntax is slightly different, the 4653address of the initrd must be augmented by it's size, in the following 4654format: "<initrd addres>:<initrd size>". 4655 4656 4657Standalone HOWTO: 4658================= 4659 4660One of the features of U-Boot is that you can dynamically load and 4661run "standalone" applications, which can use some resources of 4662U-Boot like console I/O functions or interrupt services. 4663 4664Two simple examples are included with the sources: 4665 4666"Hello World" Demo: 4667------------------- 4668 4669'examples/hello_world.c' contains a small "Hello World" Demo 4670application; it is automatically compiled when you build U-Boot. 4671It's configured to run at address 0x00040004, so you can play with it 4672like that: 4673 4674 => loads 4675 ## Ready for S-Record download ... 4676 ~>examples/hello_world.srec 4677 1 2 3 4 5 6 7 8 9 10 11 ... 4678 [file transfer complete] 4679 [connected] 4680 ## Start Addr = 0x00040004 4681 4682 => go 40004 Hello World! This is a test. 4683 ## Starting application at 0x00040004 ... 4684 Hello World 4685 argc = 7 4686 argv[0] = "40004" 4687 argv[1] = "Hello" 4688 argv[2] = "World!" 4689 argv[3] = "This" 4690 argv[4] = "is" 4691 argv[5] = "a" 4692 argv[6] = "test." 4693 argv[7] = "<NULL>" 4694 Hit any key to exit ... 4695 4696 ## Application terminated, rc = 0x0 4697 4698Another example, which demonstrates how to register a CPM interrupt 4699handler with the U-Boot code, can be found in 'examples/timer.c'. 4700Here, a CPM timer is set up to generate an interrupt every second. 4701The interrupt service routine is trivial, just printing a '.' 4702character, but this is just a demo program. The application can be 4703controlled by the following keys: 4704 4705 ? - print current values og the CPM Timer registers 4706 b - enable interrupts and start timer 4707 e - stop timer and disable interrupts 4708 q - quit application 4709 4710 => loads 4711 ## Ready for S-Record download ... 4712 ~>examples/timer.srec 4713 1 2 3 4 5 6 7 8 9 10 11 ... 4714 [file transfer complete] 4715 [connected] 4716 ## Start Addr = 0x00040004 4717 4718 => go 40004 4719 ## Starting application at 0x00040004 ... 4720 TIMERS=0xfff00980 4721 Using timer 1 4722 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4723 4724Hit 'b': 4725 [q, b, e, ?] Set interval 1000000 us 4726 Enabling timer 4727Hit '?': 4728 [q, b, e, ?] ........ 4729 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4730Hit '?': 4731 [q, b, e, ?] . 4732 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4733Hit '?': 4734 [q, b, e, ?] . 4735 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4736Hit '?': 4737 [q, b, e, ?] . 4738 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4739Hit 'e': 4740 [q, b, e, ?] ...Stopping timer 4741Hit 'q': 4742 [q, b, e, ?] ## Application terminated, rc = 0x0 4743 4744 4745Minicom warning: 4746================ 4747 4748Over time, many people have reported problems when trying to use the 4749"minicom" terminal emulation program for serial download. I (wd) 4750consider minicom to be broken, and recommend not to use it. Under 4751Unix, I recommend to use C-Kermit for general purpose use (and 4752especially for kermit binary protocol download ("loadb" command), and 4753use "cu" for S-Record download ("loads" command). See 4754http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 4755for help with kermit. 4756 4757 4758Nevertheless, if you absolutely want to use it try adding this 4759configuration to your "File transfer protocols" section: 4760 4761 Name Program Name U/D FullScr IO-Red. Multi 4762 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 4763 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 4764 4765 4766NetBSD Notes: 4767============= 4768 4769Starting at version 0.9.2, U-Boot supports NetBSD both as host 4770(build U-Boot) and target system (boots NetBSD/mpc8xx). 4771 4772Building requires a cross environment; it is known to work on 4773NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 4774need gmake since the Makefiles are not compatible with BSD make). 4775Note that the cross-powerpc package does not install include files; 4776attempting to build U-Boot will fail because <machine/ansi.h> is 4777missing. This file has to be installed and patched manually: 4778 4779 # cd /usr/pkg/cross/powerpc-netbsd/include 4780 # mkdir powerpc 4781 # ln -s powerpc machine 4782 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 4783 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 4784 4785Native builds *don't* work due to incompatibilities between native 4786and U-Boot include files. 4787 4788Booting assumes that (the first part of) the image booted is a 4789stage-2 loader which in turn loads and then invokes the kernel 4790proper. Loader sources will eventually appear in the NetBSD source 4791tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 4792meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 4793 4794 4795Implementation Internals: 4796========================= 4797 4798The following is not intended to be a complete description of every 4799implementation detail. However, it should help to understand the 4800inner workings of U-Boot and make it easier to port it to custom 4801hardware. 4802 4803 4804Initial Stack, Global Data: 4805--------------------------- 4806 4807The implementation of U-Boot is complicated by the fact that U-Boot 4808starts running out of ROM (flash memory), usually without access to 4809system RAM (because the memory controller is not initialized yet). 4810This means that we don't have writable Data or BSS segments, and BSS 4811is not initialized as zero. To be able to get a C environment working 4812at all, we have to allocate at least a minimal stack. Implementation 4813options for this are defined and restricted by the CPU used: Some CPU 4814models provide on-chip memory (like the IMMR area on MPC8xx and 4815MPC826x processors), on others (parts of) the data cache can be 4816locked as (mis-) used as memory, etc. 4817 4818 Chris Hallinan posted a good summary of these issues to the 4819 U-Boot mailing list: 4820 4821 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 4822 From: "Chris Hallinan" <clh@net1plus.com> 4823 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 4824 ... 4825 4826 Correct me if I'm wrong, folks, but the way I understand it 4827 is this: Using DCACHE as initial RAM for Stack, etc, does not 4828 require any physical RAM backing up the cache. The cleverness 4829 is that the cache is being used as a temporary supply of 4830 necessary storage before the SDRAM controller is setup. It's 4831 beyond the scope of this list to explain the details, but you 4832 can see how this works by studying the cache architecture and 4833 operation in the architecture and processor-specific manuals. 4834 4835 OCM is On Chip Memory, which I believe the 405GP has 4K. It 4836 is another option for the system designer to use as an 4837 initial stack/RAM area prior to SDRAM being available. Either 4838 option should work for you. Using CS 4 should be fine if your 4839 board designers haven't used it for something that would 4840 cause you grief during the initial boot! It is frequently not 4841 used. 4842 4843 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 4844 with your processor/board/system design. The default value 4845 you will find in any recent u-boot distribution in 4846 walnut.h should work for you. I'd set it to a value larger 4847 than your SDRAM module. If you have a 64MB SDRAM module, set 4848 it above 400_0000. Just make sure your board has no resources 4849 that are supposed to respond to that address! That code in 4850 start.S has been around a while and should work as is when 4851 you get the config right. 4852 4853 -Chris Hallinan 4854 DS4.COM, Inc. 4855 4856It is essential to remember this, since it has some impact on the C 4857code for the initialization procedures: 4858 4859* Initialized global data (data segment) is read-only. Do not attempt 4860 to write it. 4861 4862* Do not use any uninitialized global data (or implicitly initialized 4863 as zero data - BSS segment) at all - this is undefined, initiali- 4864 zation is performed later (when relocating to RAM). 4865 4866* Stack space is very limited. Avoid big data buffers or things like 4867 that. 4868 4869Having only the stack as writable memory limits means we cannot use 4870normal global data to share information between the code. But it 4871turned out that the implementation of U-Boot can be greatly 4872simplified by making a global data structure (gd_t) available to all 4873functions. We could pass a pointer to this data as argument to _all_ 4874functions, but this would bloat the code. Instead we use a feature of 4875the GCC compiler (Global Register Variables) to share the data: we 4876place a pointer (gd) to the global data into a register which we 4877reserve for this purpose. 4878 4879When choosing a register for such a purpose we are restricted by the 4880relevant (E)ABI specifications for the current architecture, and by 4881GCC's implementation. 4882 4883For PowerPC, the following registers have specific use: 4884 R1: stack pointer 4885 R2: reserved for system use 4886 R3-R4: parameter passing and return values 4887 R5-R10: parameter passing 4888 R13: small data area pointer 4889 R30: GOT pointer 4890 R31: frame pointer 4891 4892 (U-Boot also uses R12 as internal GOT pointer. r12 4893 is a volatile register so r12 needs to be reset when 4894 going back and forth between asm and C) 4895 4896 ==> U-Boot will use R2 to hold a pointer to the global data 4897 4898 Note: on PPC, we could use a static initializer (since the 4899 address of the global data structure is known at compile time), 4900 but it turned out that reserving a register results in somewhat 4901 smaller code - although the code savings are not that big (on 4902 average for all boards 752 bytes for the whole U-Boot image, 4903 624 text + 127 data). 4904 4905On ARM, the following registers are used: 4906 4907 R0: function argument word/integer result 4908 R1-R3: function argument word 4909 R9: platform specific 4910 R10: stack limit (used only if stack checking is enabled) 4911 R11: argument (frame) pointer 4912 R12: temporary workspace 4913 R13: stack pointer 4914 R14: link register 4915 R15: program counter 4916 4917 ==> U-Boot will use R9 to hold a pointer to the global data 4918 4919 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 4920 4921On Nios II, the ABI is documented here: 4922 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 4923 4924 ==> U-Boot will use gp to hold a pointer to the global data 4925 4926 Note: on Nios II, we give "-G0" option to gcc and don't use gp 4927 to access small data sections, so gp is free. 4928 4929On NDS32, the following registers are used: 4930 4931 R0-R1: argument/return 4932 R2-R5: argument 4933 R15: temporary register for assembler 4934 R16: trampoline register 4935 R28: frame pointer (FP) 4936 R29: global pointer (GP) 4937 R30: link register (LP) 4938 R31: stack pointer (SP) 4939 PC: program counter (PC) 4940 4941 ==> U-Boot will use R10 to hold a pointer to the global data 4942 4943NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 4944or current versions of GCC may "optimize" the code too much. 4945 4946On RISC-V, the following registers are used: 4947 4948 x0: hard-wired zero (zero) 4949 x1: return address (ra) 4950 x2: stack pointer (sp) 4951 x3: global pointer (gp) 4952 x4: thread pointer (tp) 4953 x5: link register (t0) 4954 x8: frame pointer (fp) 4955 x10-x11: arguments/return values (a0-1) 4956 x12-x17: arguments (a2-7) 4957 x28-31: temporaries (t3-6) 4958 pc: program counter (pc) 4959 4960 ==> U-Boot will use gp to hold a pointer to the global data 4961 4962Memory Management: 4963------------------ 4964 4965U-Boot runs in system state and uses physical addresses, i.e. the 4966MMU is not used either for address mapping nor for memory protection. 4967 4968The available memory is mapped to fixed addresses using the memory 4969controller. In this process, a contiguous block is formed for each 4970memory type (Flash, SDRAM, SRAM), even when it consists of several 4971physical memory banks. 4972 4973U-Boot is installed in the first 128 kB of the first Flash bank (on 4974TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 4975booting and sizing and initializing DRAM, the code relocates itself 4976to the upper end of DRAM. Immediately below the U-Boot code some 4977memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 4978configuration setting]. Below that, a structure with global Board 4979Info data is placed, followed by the stack (growing downward). 4980 4981Additionally, some exception handler code is copied to the low 8 kB 4982of DRAM (0x00000000 ... 0x00001FFF). 4983 4984So a typical memory configuration with 16 MB of DRAM could look like 4985this: 4986 4987 0x0000 0000 Exception Vector code 4988 : 4989 0x0000 1FFF 4990 0x0000 2000 Free for Application Use 4991 : 4992 : 4993 4994 : 4995 : 4996 0x00FB FF20 Monitor Stack (Growing downward) 4997 0x00FB FFAC Board Info Data and permanent copy of global data 4998 0x00FC 0000 Malloc Arena 4999 : 5000 0x00FD FFFF 5001 0x00FE 0000 RAM Copy of Monitor Code 5002 ... eventually: LCD or video framebuffer 5003 ... eventually: pRAM (Protected RAM - unchanged by reset) 5004 0x00FF FFFF [End of RAM] 5005 5006 5007System Initialization: 5008---------------------- 5009 5010In the reset configuration, U-Boot starts at the reset entry point 5011(on most PowerPC systems at address 0x00000100). Because of the reset 5012configuration for CS0# this is a mirror of the on board Flash memory. 5013To be able to re-map memory U-Boot then jumps to its link address. 5014To be able to implement the initialization code in C, a (small!) 5015initial stack is set up in the internal Dual Ported RAM (in case CPUs 5016which provide such a feature like), or in a locked part of the data 5017cache. After that, U-Boot initializes the CPU core, the caches and 5018the SIU. 5019 5020Next, all (potentially) available memory banks are mapped using a 5021preliminary mapping. For example, we put them on 512 MB boundaries 5022(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5023on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5024programmed for SDRAM access. Using the temporary configuration, a 5025simple memory test is run that determines the size of the SDRAM 5026banks. 5027 5028When there is more than one SDRAM bank, and the banks are of 5029different size, the largest is mapped first. For equal size, the first 5030bank (CS2#) is mapped first. The first mapping is always for address 50310x00000000, with any additional banks following immediately to create 5032contiguous memory starting from 0. 5033 5034Then, the monitor installs itself at the upper end of the SDRAM area 5035and allocates memory for use by malloc() and for the global Board 5036Info data; also, the exception vector code is copied to the low RAM 5037pages, and the final stack is set up. 5038 5039Only after this relocation will you have a "normal" C environment; 5040until that you are restricted in several ways, mostly because you are 5041running from ROM, and because the code will have to be relocated to a 5042new address in RAM. 5043 5044 5045U-Boot Porting Guide: 5046---------------------- 5047 5048[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5049list, October 2002] 5050 5051 5052int main(int argc, char *argv[]) 5053{ 5054 sighandler_t no_more_time; 5055 5056 signal(SIGALRM, no_more_time); 5057 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5058 5059 if (available_money > available_manpower) { 5060 Pay consultant to port U-Boot; 5061 return 0; 5062 } 5063 5064 Download latest U-Boot source; 5065 5066 Subscribe to u-boot mailing list; 5067 5068 if (clueless) 5069 email("Hi, I am new to U-Boot, how do I get started?"); 5070 5071 while (learning) { 5072 Read the README file in the top level directory; 5073 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5074 Read applicable doc/*.README; 5075 Read the source, Luke; 5076 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5077 } 5078 5079 if (available_money > toLocalCurrency ($2500)) 5080 Buy a BDI3000; 5081 else 5082 Add a lot of aggravation and time; 5083 5084 if (a similar board exists) { /* hopefully... */ 5085 cp -a board/<similar> board/<myboard> 5086 cp include/configs/<similar>.h include/configs/<myboard>.h 5087 } else { 5088 Create your own board support subdirectory; 5089 Create your own board include/configs/<myboard>.h file; 5090 } 5091 Edit new board/<myboard> files 5092 Edit new include/configs/<myboard>.h 5093 5094 while (!accepted) { 5095 while (!running) { 5096 do { 5097 Add / modify source code; 5098 } until (compiles); 5099 Debug; 5100 if (clueless) 5101 email("Hi, I am having problems..."); 5102 } 5103 Send patch file to the U-Boot email list; 5104 if (reasonable critiques) 5105 Incorporate improvements from email list code review; 5106 else 5107 Defend code as written; 5108 } 5109 5110 return 0; 5111} 5112 5113void no_more_time (int sig) 5114{ 5115 hire_a_guru(); 5116} 5117 5118 5119Coding Standards: 5120----------------- 5121 5122All contributions to U-Boot should conform to the Linux kernel 5123coding style; see the kernel coding style guide at 5124https://www.kernel.org/doc/html/latest/process/coding-style.html, and the 5125script "scripts/Lindent" in your Linux kernel source directory. 5126 5127Source files originating from a different project (for example the 5128MTD subsystem) are generally exempt from these guidelines and are not 5129reformatted to ease subsequent migration to newer versions of those 5130sources. 5131 5132Please note that U-Boot is implemented in C (and to some small parts in 5133Assembler); no C++ is used, so please do not use C++ style comments (//) 5134in your code. 5135 5136Please also stick to the following formatting rules: 5137- remove any trailing white space 5138- use TAB characters for indentation and vertical alignment, not spaces 5139- make sure NOT to use DOS '\r\n' line feeds 5140- do not add more than 2 consecutive empty lines to source files 5141- do not add trailing empty lines to source files 5142 5143Submissions which do not conform to the standards may be returned 5144with a request to reformat the changes. 5145 5146 5147Submitting Patches: 5148------------------- 5149 5150Since the number of patches for U-Boot is growing, we need to 5151establish some rules. Submissions which do not conform to these rules 5152may be rejected, even when they contain important and valuable stuff. 5153 5154Please see http://www.denx.de/wiki/U-Boot/Patches for details. 5155 5156Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 5157see https://lists.denx.de/listinfo/u-boot 5158 5159When you send a patch, please include the following information with 5160it: 5161 5162* For bug fixes: a description of the bug and how your patch fixes 5163 this bug. Please try to include a way of demonstrating that the 5164 patch actually fixes something. 5165 5166* For new features: a description of the feature and your 5167 implementation. 5168 5169* A CHANGELOG entry as plaintext (separate from the patch) 5170 5171* For major contributions, add a MAINTAINERS file with your 5172 information and associated file and directory references. 5173 5174* When you add support for a new board, don't forget to add a 5175 maintainer e-mail address to the boards.cfg file, too. 5176 5177* If your patch adds new configuration options, don't forget to 5178 document these in the README file. 5179 5180* The patch itself. If you are using git (which is *strongly* 5181 recommended) you can easily generate the patch using the 5182 "git format-patch". If you then use "git send-email" to send it to 5183 the U-Boot mailing list, you will avoid most of the common problems 5184 with some other mail clients. 5185 5186 If you cannot use git, use "diff -purN OLD NEW". If your version of 5187 diff does not support these options, then get the latest version of 5188 GNU diff. 5189 5190 The current directory when running this command shall be the parent 5191 directory of the U-Boot source tree (i. e. please make sure that 5192 your patch includes sufficient directory information for the 5193 affected files). 5194 5195 We prefer patches as plain text. MIME attachments are discouraged, 5196 and compressed attachments must not be used. 5197 5198* If one logical set of modifications affects or creates several 5199 files, all these changes shall be submitted in a SINGLE patch file. 5200 5201* Changesets that contain different, unrelated modifications shall be 5202 submitted as SEPARATE patches, one patch per changeset. 5203 5204 5205Notes: 5206 5207* Before sending the patch, run the buildman script on your patched 5208 source tree and make sure that no errors or warnings are reported 5209 for any of the boards. 5210 5211* Keep your modifications to the necessary minimum: A patch 5212 containing several unrelated changes or arbitrary reformats will be 5213 returned with a request to re-formatting / split it. 5214 5215* If you modify existing code, make sure that your new code does not 5216 add to the memory footprint of the code ;-) Small is beautiful! 5217 When adding new features, these should compile conditionally only 5218 (using #ifdef), and the resulting code with the new feature 5219 disabled must not need more memory than the old code without your 5220 modification. 5221 5222* Remember that there is a size limit of 100 kB per message on the 5223 u-boot mailing list. Bigger patches will be moderated. If they are 5224 reasonable and not too big, they will be acknowledged. But patches 5225 bigger than the size limit should be avoided. 5226