- i386 Files specific to i386 CPUs
- ixp Files specific to Intel XScale IXP CPUs
- mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
+ - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
+ - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
+ - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
+ - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
- mips Files specific to MIPS CPUs
- mpc5xx Files specific to Freescale MPC5xx CPUs
- mpc5xxx Files specific to Freescale MPC5xxx CPUs
The following options need to be configured:
-- CPU Type: Define exactly one of
-
- PowerPC based CPUs:
- -------------------
- CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
- or CONFIG_MPC5xx
- or CONFIG_MPC8220
- or CONFIG_MPC824X, CONFIG_MPC8260
- or CONFIG_MPC85xx
- or CONFIG_IOP480
- or CONFIG_405GP
- or CONFIG_405EP
- or CONFIG_440
- or CONFIG_MPC74xx
- or CONFIG_750FX
-
- ARM based CPUs:
- ---------------
- CONFIG_SA1110
- CONFIG_ARM7
- CONFIG_PXA250
- CONFIG_CPU_MONAHANS
-
- MicroBlaze based CPUs:
- ----------------------
- CONFIG_MICROBLAZE
-
- Nios-2 based CPUs:
- ----------------------
- CONFIG_NIOS2
-
- AVR32 based CPUs:
- ----------------------
- CONFIG_AT32AP
-
-- Board Type: Define exactly one of
-
- PowerPC based boards:
- ---------------------
-
- CONFIG_ADCIOP CONFIG_FPS860L CONFIG_OXC
- CONFIG_ADS860 CONFIG_GEN860T CONFIG_PCI405
- CONFIG_AMX860 CONFIG_GENIETV CONFIG_PCIPPC2
- CONFIG_AP1000 CONFIG_GTH CONFIG_PCIPPC6
- CONFIG_AR405 CONFIG_gw8260 CONFIG_pcu_e
- CONFIG_BAB7xx CONFIG_hermes CONFIG_PIP405
- CONFIG_BC3450 CONFIG_hymod CONFIG_PM826
- CONFIG_c2mon CONFIG_IAD210 CONFIG_ppmc8260
- CONFIG_CANBT CONFIG_ICU862 CONFIG_QS823
- CONFIG_CCM CONFIG_IP860 CONFIG_QS850
- CONFIG_CMI CONFIG_IPHASE4539 CONFIG_QS860T
- CONFIG_cogent_mpc8260 CONFIG_IVML24 CONFIG_RBC823
- CONFIG_cogent_mpc8xx CONFIG_IVML24_128 CONFIG_RPXClassic
- CONFIG_CPCI405 CONFIG_IVML24_256 CONFIG_RPXlite
- CONFIG_CPCI4052 CONFIG_IVMS8 CONFIG_RPXsuper
- CONFIG_CPCIISER4 CONFIG_IVMS8_128 CONFIG_rsdproto
- CONFIG_CPU86 CONFIG_IVMS8_256 CONFIG_sacsng
- CONFIG_CRAYL1 CONFIG_JSE CONFIG_Sandpoint8240
- CONFIG_CSB272 CONFIG_LANTEC CONFIG_Sandpoint8245
- CONFIG_CU824 CONFIG_LITE5200B CONFIG_sbc8260
- CONFIG_DASA_SIM CONFIG_lwmon CONFIG_sbc8560
- CONFIG_DB64360 CONFIG_MBX CONFIG_SM850
- CONFIG_DB64460 CONFIG_MBX860T CONFIG_SPD823TS
- CONFIG_DU405 CONFIG_MHPC CONFIG_STXGP3
- CONFIG_DUET_ADS CONFIG_MIP405 CONFIG_SXNI855T
- CONFIG_EBONY CONFIG_MOUSSE CONFIG_TQM823L
- CONFIG_ELPPC CONFIG_MPC8260ADS CONFIG_TQM8260
- CONFIG_ELPT860 CONFIG_MPC8540ADS CONFIG_TQM850L
- CONFIG_ep8260 CONFIG_MPC8540EVAL CONFIG_TQM855L
- CONFIG_ERIC CONFIG_MPC8560ADS CONFIG_TQM860L
- CONFIG_ESTEEM192E CONFIG_MUSENKI CONFIG_TTTech
- CONFIG_ETX094 CONFIG_MVS1 CONFIG_UTX8245
- CONFIG_EVB64260 CONFIG_NETPHONE CONFIG_V37
- CONFIG_FADS823 CONFIG_NETTA CONFIG_W7OLMC
- CONFIG_FADS850SAR CONFIG_NETVIA CONFIG_W7OLMG
- CONFIG_FADS860T CONFIG_NX823 CONFIG_WALNUT
- CONFIG_FLAGADM CONFIG_OCRTC CONFIG_ZPC1900
- CONFIG_FPS850L CONFIG_ORSG CONFIG_ZUMA
-
- ARM based boards:
- -----------------
-
- CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250,
- CONFIG_CSB637, CONFIG_DELTA, CONFIG_DNP1110,
- CONFIG_EP7312, CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE,
- CONFIG_IMPA7, CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610,
- CONFIG_KB9202, CONFIG_LART, CONFIG_LPD7A400,
- CONFIG_LUBBOCK, CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4,
- CONFIG_PLEB2, CONFIG_SHANNON, CONFIG_P2_OMAP730,
- CONFIG_SMDK2400, CONFIG_SMDK2410, CONFIG_TRAB,
- CONFIG_VCMA9
-
- MicroBlaze based boards:
- ------------------------
-
- CONFIG_SUZAKU
-
- Nios-2 based boards:
- ------------------------
-
- CONFIG_PCI5441 CONFIG_PK1C20
- CONFIG_EP1C20 CONFIG_EP1S10 CONFIG_EP1S40
-
- AVR32 based boards:
- -------------------
-
- CONFIG_ATSTK1000
+- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
-- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
- Define exactly one of
- CONFIG_ATSTK1002
+- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
+- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
+ Define exactly one, e.g. CONFIG_ATSTK1002
- CPU Module Type: (if CONFIG_COGENT is defined)
Define exactly one of
CONFIG_OF_LIBFDT
* New libfdt-based support
* Adds the "fdt" command
- * The bootm command does _not_ modify the fdt
+ * The bootm command automatically updates the fdt
CONFIG_OF_FLAT_TREE
* Deprecated, see CONFIG_OF_LIBFDT
* The environment variable "disable_of", when set,
disables this functionality.
- CONFIG_OF_FLAT_TREE_MAX_SIZE
-
- The maximum size of the constructed OF tree.
-
OF_CPU - The proper name of the cpus node.
OF_SOC - The proper name of the soc node.
OF_TBCLK - The timebase frequency.
OF_STDOUT_PATH - The path to the console device
+ boards with QUICC Engines require OF_QE to set UCC mac addresses
+
CONFIG_OF_HAS_BD_T
* CONFIG_OF_LIBFDT - enables the "fdt bd_t" command
CONFIG_OF_HAS_UBOOT_ENV
- * CONFIG_OF_LIBFDT - enables the "fdt bd_t" command
+ * CONFIG_OF_LIBFDT - enables the "fdt env" command
* CONFIG_OF_FLAT_TREE - The resulting flat device tree
will have a copy of u-boot's environment variables
CONFIG_USB_CONFIG
for differential drivers: 0x00001000
for single ended drivers: 0x00005000
+ CFG_USB_EVENT_POLL
+ May be defined to allow interrupt polling
+ instead of using asynchronous interrupts
+
+- USB Device:
+ Define the below if you wish to use the USB console.
+ Once firmware is rebuilt from a serial console issue the
+ command "setenv stdin usbtty; setenv stdout usbtty" and
+ attach your usb cable. The Unix command "dmesg" should print
+ it has found a new device. The environment variable usbtty
+ can be set to gserial or cdc_acm to enable your device to
+ appear to a USB host as a Linux gserial device or a
+ Common Device Class Abstract Control Model serial device.
+ If you select usbtty = gserial you should be able to enumerate
+ a Linux host by
+ # modprobe usbserial vendor=0xVendorID product=0xProductID
+ else if using cdc_acm, simply setting the environment
+ variable usbtty to be cdc_acm should suffice. The following
+ might be defined in YourBoardName.h
+
+ CONFIG_USB_DEVICE
+ Define this to build a UDC device
+
+ CONFIG_USB_TTY
+ Define this to have a tty type of device available to
+ talk to the UDC device
+
+ CFG_CONSOLE_IS_IN_ENV
+ Define this if you want stdin, stdout &/or stderr to
+ be set to usbtty.
+
+ mpc8xx:
+ CFG_USB_EXTC_CLK 0xBLAH
+ Derive USB clock from external clock "blah"
+ - CFG_USB_EXTC_CLK 0x02
+
+ CFG_USB_BRG_CLK 0xBLAH
+ Derive USB clock from brgclk
+ - CFG_USB_BRG_CLK 0x04
+
+ If you have a USB-IF assigned VendorID then you may wish to
+ define your own vendor specific values either in BoardName.h
+ or directly in usbd_vendor_info.h. If you don't define
+ CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
+ CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
+ should pretend to be a Linux device to it's target host.
+
+ CONFIG_USBD_MANUFACTURER
+ Define this string as the name of your company for
+ - CONFIG_USBD_MANUFACTURER "my company"
+
+ CONFIG_USBD_PRODUCT_NAME
+ Define this string as the name of your product
+ - CONFIG_USBD_PRODUCT_NAME "acme usb device"
+
+ CONFIG_USBD_VENDORID
+ Define this as your assigned Vendor ID from the USB
+ Implementors Forum. This *must* be a genuine Vendor ID
+ to avoid polluting the USB namespace.
+ - CONFIG_USBD_VENDORID 0xFFFF
+
+ CONFIG_USBD_PRODUCTID
+ Define this as the unique Product ID
+ for your device
+ - CONFIG_USBD_PRODUCTID 0xFFFF
- MMC Support:
(i.e. setenv videomode 317; saveenv; reset;)
- "videomode=bootargs" all the video parameters are parsed
- from the bootargs. (See drivers/videomodes.c)
+ from the bootargs. (See drivers/video/videomodes.c)
CONFIG_VIDEO_SED13806
Defines a default value for theIP address of a TFTP
server to contact when using the "tftboot" command.
+- Multicast TFTP Mode:
+ CONFIG_MCAST_TFTP
+
+ Defines whether you want to support multicast TFTP as per
+ rfc-2090; for example to work with atftp. Lets lots of targets
+ tftp down the same boot image concurrently. Note: the ethernet
+ driver in use must provide a function: mcast() to join/leave a
+ multicast group.
+
+ CONFIG_BOOTP_RANDOM_DELAY
- BOOTP Recovery Mode:
CONFIG_BOOTP_RANDOM_DELAY
boot, thus flooding the BOOTP server. Defining
CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
inserted before sending out BOOTP requests. The
- following delays are insterted then:
+ following delays are inserted then:
1st BOOTP request: delay 0 ... 1 sec
2nd BOOTP request: delay 0 ... 2 sec
CONFIG_BOOTP_TIMEOFFSET
CONFIG_BOOTP_VENDOREX
+ CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
+ environment variable, not the BOOTP server.
+
CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
serverip from a DHCP server, it is possible that more
than one DNS serverip is offered to the client.
CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
to do a dynamic update of a DNS server. To do this, they
need the hostname of the DHCP requester.
- If CONFIG_BOOP_SEND_HOSTNAME is defined, the content
+ If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
of the "hostname" environment variable is passed as
option 12 to the DHCP server.
CONFIG_FSL_I2C
Define this option if you want to use Freescale's I2C driver in
- drivers/fsl_i2c.c.
+ drivers/i2c/fsl_i2c.c.
- SPI Support: CONFIG_SPI
SPI configuration items (port pins to use, etc). For
an example, see include/configs/sacsng.h.
-- FPGA Support: CONFIG_FPGA_COUNT
+ CONFIG_HARD_SPI
- Specify the number of FPGA devices to support.
+ Enables a hardware SPI driver for general-purpose reads
+ and writes. As with CONFIG_SOFT_SPI, the board configuration
+ must define a list of chip-select function pointers.
+ Currently supported on some MPC8xxx processors. For an
+ example, see include/configs/mpc8349emds.h.
+
+- FPGA Support: CONFIG_FPGA
+
+ Enables FPGA subsystem.
+
+ CONFIG_FPGA_<vendor>
- CONFIG_FPGA
+ Enables support for specific chip vendors.
+ (ALTERA, XILINX)
- Used to specify the types of FPGA devices. For example,
- #define CONFIG_FPGA CFG_XILINX_VIRTEX2
+ CONFIG_FPGA_<family>
+
+ Enables support for FPGA family.
+ (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
+
+ CONFIG_FPGA_COUNT
+
+ Specify the number of FPGA devices to support.
CFG_FPGA_PROG_FEEDBACK
example, some LED's) on your board. At the moment,
the following checkpoints are implemented:
+Legacy uImage format:
+
Arg Where When
1 common/cmd_bootm.c before attempting to boot an image
-1 common/cmd_bootm.c Image header has bad magic number
4 common/cmd_bootm.c Image data has correct checksum
-4 common/cmd_bootm.c Image is for unsupported architecture
5 common/cmd_bootm.c Architecture check OK
- -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
+ -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
6 common/cmd_bootm.c Image Type check OK
-6 common/cmd_bootm.c gunzip uncompression error
-7 common/cmd_bootm.c Unimplemented compression type
7 common/cmd_bootm.c Uncompression OK
- -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
- 8 common/cmd_bootm.c Image Type check OK
+ 8 common/cmd_bootm.c No uncompress/copy overwrite error
-9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
- 9 common/cmd_bootm.c Start initial ramdisk verification
- -10 common/cmd_bootm.c Ramdisk header has bad magic number
- -11 common/cmd_bootm.c Ramdisk header has bad checksum
- 10 common/cmd_bootm.c Ramdisk header is OK
- -12 common/cmd_bootm.c Ramdisk data has bad checksum
- 11 common/cmd_bootm.c Ramdisk data has correct checksum
- 12 common/cmd_bootm.c Ramdisk verification complete, start loading
- -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
- 13 common/cmd_bootm.c Start multifile image verification
- 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
- 15 common/cmd_bootm.c All preparation done, transferring control to OS
+
+ 9 common/image.c Start initial ramdisk verification
+ -10 common/image.c Ramdisk header has bad magic number
+ -11 common/image.c Ramdisk header has bad checksum
+ 10 common/image.c Ramdisk header is OK
+ -12 common/image.c Ramdisk data has bad checksum
+ 11 common/image.c Ramdisk data has correct checksum
+ 12 common/image.c Ramdisk verification complete, start loading
+ -13 common/image.c Wrong Image Type (not PPC Linux Ramdisk)
+ 13 common/image.c Start multifile image verification
+ 14 common/image.c No initial ramdisk, no multifile, continue.
+
+ 15 lib_<arch>/bootm.c All preparation done, transferring control to OS
-30 lib_ppc/board.c Fatal error, hang the system
-31 post/post.c POST test failed, detected by post_output_backlog()
-83 common/cmd_net.c some error in automatic boot or autoscript
84 common/cmd_net.c end without errors
+FIT uImage format:
+
+ Arg Where When
+ 100 common/cmd_bootm.c Kernel FIT Image has correct format
+ -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
+ 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
+ -101 common/cmd_bootm.c Can't get configuration for kernel subimage
+ 102 common/cmd_bootm.c Kernel unit name specified
+ -103 common/cmd_bootm.c Can't get kernel subimage node offset
+ 103 common/cmd_bootm.c Found configuration node
+ 104 common/cmd_bootm.c Got kernel subimage node offset
+ -104 common/cmd_bootm.c Kernel subimage hash verification failed
+ 105 common/cmd_bootm.c Kernel subimage hash verification OK
+ -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
+ 106 common/cmd_bootm.c Architecture check OK
+ -106 common/cmd_bootm.c Kernel subimage has wrong typea
+ 107 common/cmd_bootm.c Kernel subimge type OK
+ -107 common/cmd_bootm.c Can't get kernel subimage data/size
+ 108 common/cmd_bootm.c Got kernel subimage data/size
+ -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
+ -109 common/cmd_bootm.c Can't get kernel subimage type
+ -110 common/cmd_bootm.c Can't get kernel subimage comp
+ -111 common/cmd_bootm.c Can't get kernel subimage os
+ -112 common/cmd_bootm.c Can't get kernel subimage load address
+ -113 common/cmd_bootm.c Image uncompress/copy overwrite error
+
+ 120 common/image.c Start initial ramdisk verification
+ -120 common/image.c Ramdisk FIT image has incorrect format
+ 121 common/image.c Ramdisk FIT image has correct format
+ 122 common/image.c No Ramdisk subimage unit name, using configuration
+ -122 common/image.c Can't get configuration for ramdisk subimage
+ 123 common/image.c Ramdisk unit name specified
+ -124 common/image.c Can't get ramdisk subimage node offset
+ 125 common/image.c Got ramdisk subimage node offset
+ -125 common/image.c Ramdisk subimage hash verification failed
+ 126 common/image.c Ramdisk subimage hash verification OK
+ -126 common/image.c Ramdisk subimage for unsupported architecture
+ 127 common/image.c Architecture check OK
+ -127 common/image.c Can't get ramdisk subimage data/size
+ 128 common/image.c Got ramdisk subimage data/size
+ 129 common/image.c Can't get ramdisk load address
+ -129 common/image.c Got ramdisk load address
+
+ -130 common/cmd_doc.c Icorrect FIT image format
+ 131 common/cmd_doc.c FIT image format OK
+
+ -140 common/cmd_ide.c Icorrect FIT image format
+ 141 common/cmd_ide.c FIT image format OK
+
+ -150 common/cmd_nand.c Icorrect FIT image format
+ 151 common/cmd_nand.c FIT image format OK
+
+
Modem Support:
--------------
to be a good choice since it makes it far enough from the
start of the data area as well as from the stack pointer.
-Please note that the environment is read-only as long as the monitor
+Please note that the environment is read-only until the monitor
has been relocated to RAM and a RAM copy of the environment has been
created; also, when using EEPROM you will have to use getenv_r()
until then to read environment variables.
enable I2C microcode relocation patch (MPC8xx);
define relocation offset in DPRAM [DSP2]
+- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]:
+ enable SMC microcode relocation patch (MPC8xx);
+ define relocation offset in DPRAM [SMC1]
+
- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
enable SPI microcode relocation patch (MPC8xx);
define relocation offset in DPRAM [SCC4]
make NAME_config
where "NAME_config" is the name of one of the existing
-configurations; the following names are supported:
-
- ADCIOP_config FPS860L_config omap730p2_config
- ADS860_config GEN860T_config pcu_e_config
- Alaska8220_config
- AR405_config GENIETV_config PIP405_config
- at91rm9200dk_config GTH_config QS823_config
- CANBT_config hermes_config QS850_config
- cmi_mpc5xx_config hymod_config QS860T_config
- cogent_common_config IP860_config RPXlite_config
- cogent_mpc8260_config IVML24_config RPXlite_DW_config
- cogent_mpc8xx_config IVMS8_config RPXsuper_config
- CPCI405_config JSE_config rsdproto_config
- CPCIISER4_config LANTEC_config Sandpoint8240_config
- csb272_config lwmon_config sbc8260_config
- CU824_config MBX860T_config sbc8560_33_config
- DUET_ADS_config MBX_config sbc8560_66_config
- EBONY_config mpc7448hpc2_config SM850_config
- ELPT860_config MPC8260ADS_config SPD823TS_config
- ESTEEM192E_config MPC8540ADS_config stxgp3_config
- ETX094_config MPC8540EVAL_config SXNI855T_config
- FADS823_config NMPC8560ADS_config TQM823L_config
- FADS850SAR_config NETVIA_config TQM850L_config
- FADS860T_config omap1510inn_config TQM855L_config
- FPS850L_config omap1610h2_config TQM860L_config
- omap1610inn_config walnut_config
- omap5912osk_config Yukon8220_config
- omap2420h4_config ZPC1900_config
+configurations; see the main Makefile for supported names.
Note: for some board special configuration names may exist; check if
additional information is available from the board vendor; for
configuration from the BOOTP server, but not try to
load any image using TFTP
+ autoscript - if set to "yes" commands like "loadb", "loady",
+ "bootp", "tftpb", "rarpboot" and "nfs" will attempt
+ to automatically run script images (by internally
+ calling "autoscript").
+
+ autoscript_uname - if script image is in a format (FIT) this
+ variable is used to get script subimage unit name.
+
autostart - if set to "yes", an image loaded using the "bootp",
"rarpboot", "tftpboot" or "diskboot" commands will
be automatically started (by internally calling
=> setenv ethact SCC ETHERNET
=> ping 10.0.0.1 # traffic sent on SCC ETHERNET
+ ethrotate - When set to "no" U-Boot does not go through all
+ available network interfaces.
+ It just stays at the currently selected interface.
+
netretry - When set to "no" each network operation will
either succeed or fail without retrying.
When set to "once" the network operation will
Useful on scripts which control the retry operation
themselves.
+ npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD
+ if set load address for the npe microcode
+
tftpsrcport - If this is set, the value is used for TFTP's
UDP source port.
Image Formats:
==============
-The "boot" commands of this monitor operate on "image" files which
-can be basicly anything, preceeded by a special header; see the
-definitions in include/image.h for details; basicly, the header
-defines the following image properties:
+U-Boot is capable of booting (and performing other auxiliary operations on)
+images in two formats:
+
+New uImage format (FIT)
+-----------------------
+
+Flexible and powerful format based on Flattened Image Tree -- FIT (similar
+to Flattened Device Tree). It allows the use of images with multiple
+components (several kernels, ramdisks, etc.), with contents protected by
+SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
+
+
+Old uImage format
+-----------------
+
+Old image format is based on binary files which can be basically anything,
+preceded by a special header; see the definitions in include/image.h for
+details; basically, the header defines the following image properties:
* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
For PowerPC, the following registers have specific use:
R1: stack pointer
- R2: TOC pointer
+ R2: reserved for system use
R3-R4: parameter passing and return values
R5-R10: parameter passing
R13: small data area pointer
(U-Boot also uses R14 as internal GOT pointer.)
- ==> U-Boot will use R29 to hold a pointer to the global data
+ ==> U-Boot will use R2 to hold a pointer to the global data
Note: on PPC, we could use a static initializer (since the
address of the global data structure is known at compile time),
average for all boards 752 bytes for the whole U-Boot image,
624 text + 127 data).
+On Blackfin, the normal C ABI (except for P5) is followed as documented here:
+ http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
+
+ ==> U-Boot will use P5 to hold a pointer to the global data
+
On ARM, the following registers are used:
R0: function argument word/integer result
projects / u-boot / blobdiff