#
-# (C) Copyright 2000 - 2011
+# (C) Copyright 2000 - 2012
# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
#
# See file CREDITS for list of people who contributed to this
releases in "stable" maintenance trees.
Examples:
- U-Boot v2009.11 - Release November 2009
+ U-Boot v2009.11 - Release November 2009
U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
Defines the string to utilize when trying to match PCIe device
tree nodes for the given platform.
+- Generic CPU options:
+ CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
+
+ Defines the endianess of the CPU. Implementation of those
+ values is arch specific.
+
- Intel Monahans options:
CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
XWAY SoCs for booting from NOR flash. The U-Boot image needs to
be swapped if a flash programmer is used.
+- ARM options:
+ CONFIG_SYS_EXCEPTION_VECTORS_HIGH
+
+ Select high exception vectors of the ARM core, e.g., do not
+ clear the V bit of the c1 register of CP15.
+
- Linux Kernel Interface:
CONFIG_CLOCKS_IN_MHZ
CONFIG_CFB_CONSOLE
Enables console device for a color framebuffer. Needs following
- defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
+ defines (cf. smiLynxEM, i8042)
VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
(default big endian)
VIDEO_HW_RECTFILL graphic chip supports
'Sane' compilers will generate smaller code if
CONFIG_PRE_CON_BUF_SZ is a power of 2
+- Safe printf() functions
+ Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
+ the printf() functions. These are defined in
+ include/vsprintf.h and include snprintf(), vsnprintf() and
+ so on. Code size increase is approximately 300-500 bytes.
+ If this option is not given then these functions will
+ silently discard their buffer size argument - this means
+ you are not getting any overflow checking in this case.
+
- Boot Delay: CONFIG_BOOTDELAY - in seconds
Delay before automatically booting the default image;
set to -1 to disable autoboot.
CONFIG_CMD_NAND * NAND support
CONFIG_CMD_NET bootp, tftpboot, rarpboot
CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
- CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
+ CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
CONFIG_CMD_PCI * pciinfo
CONFIG_CMD_PCMCIA * PCMCIA support
CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
(requires CONFIG_CMD_I2C)
CONFIG_CMD_SETGETDCR Support for DCR Register access
(4xx only)
+ CONFIG_CMD_SF * Read/write/erase SPI NOR flash
CONFIG_CMD_SHA1SUM print sha1 memory digest
(requires CONFIG_CMD_MEMORY)
CONFIG_CMD_SOURCE "source" command Support
experimental and only available on a few boards. The device
tree is available in the global data as gd->fdt_blob.
- U-Boot needs to get its device tree from somewhere. At present
- the only way is to embed it in the image with CONFIG_OF_EMBED.
+ U-Boot needs to get its device tree from somewhere. This can
+ be done using one of the two options below:
CONFIG_OF_EMBED
If this variable is defined, U-Boot will embed a device tree
is then picked up in board_init_f() and made available through
the global data structure as gd->blob.
+ CONFIG_OF_SEPARATE
+ If this variable is defined, U-Boot will build a device tree
+ binary. It will be called u-boot.dtb. Architecture-specific
+ code will locate it at run-time. Generally this works by:
+
+ cat u-boot.bin u-boot.dtb >image.bin
+
+ and in fact, U-Boot does this for you, creating a file called
+ u-boot-dtb.bin which is useful in the common case. You can
+ still use the individual files if you need something more
+ exotic.
+
- Watchdog:
CONFIG_WATCHDOG
If this variable is defined, it enables watchdog
CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
- CONFIG_RTC_MC13783 - use MC13783 RTC
+ CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
CONFIG_RTC_MC146818 - use MC146818 RTC
CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
- NETWORK Support (PCI):
CONFIG_E1000
- Support for Intel 8254x gigabit chips.
+ Support for Intel 8254x/8257x gigabit chips.
+
+ CONFIG_E1000_SPI
+ Utility code for direct access to the SPI bus on Intel 8257x.
+ This does not do anything useful unless you set at least one
+ of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
+
+ CONFIG_E1000_SPI_GENERIC
+ Allow generic access to the SPI bus on the Intel 8257x, for
+ example with the "sspi" command.
+
+ CONFIG_CMD_E1000
+ Management command for E1000 devices. When used on devices
+ with SPI support you can reprogram the EEPROM from U-Boot.
CONFIG_E1000_FALLBACK_MAC
default MAC for empty EEPROM after production.
If this defined, the driver is quiet.
The driver doen't show link status messages.
+ CONFIG_CALXEDA_XGMAC
+ Support for the Calxeda XGMAC device
+
CONFIG_DRIVER_LAN91C96
Support for SMSC's LAN91C96 chips.
Define this to use i/o functions instead of macros
(some hardware wont work with macros)
+ CONFIG_DRIVER_TI_EMAC
+ Support for davinci emac
+
+ CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
+ Define this if you have more then 3 PHYs.
+
CONFIG_FTGMAC100
Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
CONFIG_SH_ETHER_CACHE_WRITEBACK
If this option is set, the driver enables cache flush.
+- TPM Support:
+ CONFIG_GENERIC_LPC_TPM
+ Support for generic parallel port TPM devices. Only one device
+ per system is supported at this time.
+
+ CONFIG_TPM_TIS_BASE_ADDRESS
+ Base address where the generic TPM device is mapped
+ to. Contemporary x86 systems usually map it at
+ 0xfed40000.
+
- USB Support:
At the moment only the UHCI host controller is
supported (PIP405, MIP405, MPC5200); define
May be defined to allow interrupt polling
instead of using asynchronous interrupts
+ CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
+ txfilltuning field in the EHCI controller on reset.
+
- USB Device:
Define the below if you wish to use the USB console.
Once firmware is rebuilt from a serial console issue the
Define this to have a tty type of device available to
talk to the UDC device
+ CONFIG_USBD_HS
+ Define this to enable the high speed support for usb
+ device and usbtty. If this feature is enabled, a routine
+ int is_usbd_high_speed(void)
+ also needs to be defined by the driver to dynamically poll
+ whether the enumeration has succeded at high speed or full
+ speed.
+
CONFIG_SYS_CONSOLE_IS_IN_ENV
Define this if you want stdin, stdout &/or stderr to
be set to usbtty.
for your device
- CONFIG_USBD_PRODUCTID 0xFFFF
+- ULPI Layer Support:
+ The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
+ the generic ULPI layer. The generic layer accesses the ULPI PHY
+ via the platform viewport, so you need both the genric layer and
+ the viewport enabled. Currently only Chipidea/ARC based
+ viewport is supported.
+ To enable the ULPI layer support, define CONFIG_USB_ULPI and
+ CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
- MMC Support:
The MMC controller on the Intel PXA is supported. To
to disable the command chpart. This is the default when you
have not defined a custom partition
+- FAT(File Allocation Table) filesystem write function support:
+ CONFIG_FAT_WRITE
+
+ Define this to enable support for saving memory data as a
+ file in FAT formatted partition.
+
+ This will also enable the command "fatwrite" enabling the
+ user to write files to FAT.
+
- Keyboard Support:
CONFIG_ISA_KEYBOARD
Define a default value for the IP address to use for
the default Ethernet interface, in case this is not
determined through e.g. bootp.
+ (Environment variable "ipaddr")
- Server IP address:
CONFIG_SERVERIP
Defines a default value for the IP address of a TFTP
server to contact when using the "tftboot" command.
+ (Environment variable "serverip")
CONFIG_KEEP_SERVERADDR
Keeps the server's MAC address, in the env 'serveraddr'
for passing to bootargs (like Linux's netconsole option)
+- Gateway IP address:
+ CONFIG_GATEWAYIP
+
+ Defines a default value for the IP address of the
+ default router where packets to other networks are
+ sent to.
+ (Environment variable "gatewayip")
+
+- Subnet mask:
+ CONFIG_NETMASK
+
+ Defines a default value for the subnet mask (or
+ routing prefix) which is used to determine if an IP
+ address belongs to the local subnet or needs to be
+ forwarded through a router.
+ (Environment variable "netmask")
+
- Multicast TFTP Mode:
CONFIG_MCAST_TFTP
CONFIG_I2C_MULTI_BUS
This option allows the use of multiple I2C buses, each of which
- must have a controller. At any point in time, only one bus is
- active. To switch to a different bus, use the 'i2c dev' command.
+ must have a controller. At any point in time, only one bus is
+ active. To switch to a different bus, use the 'i2c dev' command.
Note that bus numbering is zero-based.
CONFIG_SYS_I2C_NOPROBES
This option specifies a list of I2C devices that will be skipped
- when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
+ when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
is set, specify a list of bus-device pairs. Otherwise, specify
a 1D array of device addresses
e.g.
#undef CONFIG_I2C_MULTI_BUS
- #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
+ #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
will skip addresses 0x50 and 0x68 on a board with one I2C bus
- #define CONFIG_I2C_MULTI_BUS
+ #define CONFIG_I2C_MULTI_BUS
#define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
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
+ Currently supported on some MPC8xxx processors. For an
example, see include/configs/mpc8349emds.h.
CONFIG_MXC_SPI
Enables the driver for the SPI controllers on i.MX and MXC
- SoCs. Currently only i.MX31 is supported.
+ SoCs. Currently i.MX31/35/51 are supported.
- FPGA Support: CONFIG_FPGA
allows to read/write in Dataflash via the standard
commands cp, md...
+- Serial Flash support
+ CONFIG_CMD_SF
+
+ Defining this option enables SPI flash commands
+ 'sf probe/read/write/erase/update'.
+
+ Usage requires an initial 'probe' to define the serial
+ flash parameters, followed by read/write/erase/update
+ commands.
+
+ The following defaults may be provided by the platform
+ to handle the common case when only a single serial
+ flash is present on the system.
+
+ CONFIG_SF_DEFAULT_BUS Bus identifier
+ CONFIG_SF_DEFAULT_CS Chip-select
+ CONFIG_SF_DEFAULT_MODE (see include/spi.h)
+ CONFIG_SF_DEFAULT_SPEED in Hz
+
- SystemACE Support:
CONFIG_SYSTEMACE
example, some LED's) on your board. At the moment,
the following checkpoints are implemented:
+- Detailed boot stage timing
+ CONFIG_BOOTSTAGE
+ Define this option to get detailed timing of each stage
+ of the boot process.
+
+ CONFIG_BOOTSTAGE_USER_COUNT
+ This is the number of available user bootstage records.
+ Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
+ a new ID will be allocated from this stash. If you exceed
+ the limit, recording will stop.
+
+ CONFIG_BOOTSTAGE_REPORT
+ Define this to print a report before boot, similar to this:
+
+ Timer summary in microseconds:
+ Mark Elapsed Stage
+ 0 0 reset
+ 3,575,678 3,575,678 board_init_f start
+ 3,575,695 17 arch_cpu_init A9
+ 3,575,777 82 arch_cpu_init done
+ 3,659,598 83,821 board_init_r start
+ 3,910,375 250,777 main_loop
+ 29,916,167 26,005,792 bootm_start
+ 30,361,327 445,160 start_kernel
+
Legacy uImage format:
Arg Where When
13 common/image.c Start multifile image verification
14 common/image.c No initial ramdisk, no multifile, continue.
- 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
+ 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
-30 arch/powerpc/lib/board.c Fatal error, hang the system
-31 post/post.c POST test failed, detected by post_output_backlog()
CONFIG_SPL
Enable building of SPL globally.
+ CONFIG_SPL_LDSCRIPT
+ LDSCRIPT for linking the SPL binary.
+
+ CONFIG_SPL_MAX_SIZE
+ Maximum binary size (text, data and rodata) of the SPL binary.
+
CONFIG_SPL_TEXT_BASE
TEXT_BASE for linking the SPL binary.
- CONFIG_SPL_LDSCRIPT
- LDSCRIPT for linking the SPL binary.
+ CONFIG_SPL_BSS_START_ADDR
+ Link address for the BSS within the SPL binary.
+
+ CONFIG_SPL_BSS_MAX_SIZE
+ Maximum binary size of the BSS section of the SPL binary.
+
+ CONFIG_SPL_STACK
+ Adress of the start of the stack SPL will use
+
+ CONFIG_SYS_SPL_MALLOC_START
+ Starting address of the malloc pool used in SPL.
+
+ CONFIG_SYS_SPL_MALLOC_SIZE
+ The size of the malloc pool used in SPL.
CONFIG_SPL_LIBCOMMON_SUPPORT
Support for common/libcommon.o in SPL binary
CONFIG_SPL_MMC_SUPPORT
Support for drivers/mmc/libmmc.o in SPL binary
+ CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
+ CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
+ CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
+ Address, size and partition on the MMC to load U-Boot from
+ when the MMC is being used in raw mode.
+
+ CONFIG_SPL_FAT_SUPPORT
+ Support for fs/fat/libfat.o in SPL binary
+
+ CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
+ Filename to read to load U-Boot when reading from FAT
+
+ CONFIG_SPL_NAND_SIMPLE
+ Support for drivers/mtd/nand/libnand.o in SPL binary
+
+ CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
+ CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
+ CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
+ CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
+ CONFIG_SYS_NAND_ECCBYTES
+ Defines the size and behavior of the NAND that SPL uses
+ to read U-Boot with CONFIG_SPL_NAND_SIMPLE
+
+ CONFIG_SYS_NAND_U_BOOT_OFFS
+ Location in NAND for CONFIG_SPL_NAND_SIMPLE to read U-Boot
+ from.
+
+ CONFIG_SYS_NAND_U_BOOT_START
+ Location in memory for CONFIG_SPL_NAND_SIMPLE to load U-Boot
+ to.
+
+ CONFIG_SYS_NAND_HW_ECC_OOBFIRST
+ Define this if you need to first read the OOB and then the
+ data. This is used for example on davinci plattforms.
+
+ CONFIG_SPL_OMAP3_ID_NAND
+ Support for an OMAP3-specific set of functions to return the
+ ID and MFR of the first attached NAND chip, if present.
+
CONFIG_SPL_SERIAL_SUPPORT
Support for drivers/serial/libserial.o in SPL binary
CONFIG_SPL_SPI_SUPPORT
Support for drivers/spi/libspi.o in SPL binary
- CONFIG_SPL_FAT_SUPPORT
- Support for fs/fat/libfat.o in SPL binary
-
CONFIG_SPL_LIBGENERIC_SUPPORT
Support for lib/libgeneric.o in SPL binary
See also: doc/README.Modem
+Board initialization settings:
+------------------------------
+
+During Initialization u-boot calls a number of board specific functions
+to allow the preparation of board specific prerequisites, e.g. pin setup
+before drivers are initialized. To enable these callbacks the
+following configuration macros have to be defined. Currently this is
+architecture specific, so please check arch/your_architecture/lib/board.c
+typically in board_init_f() and board_init_r().
+
+- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
+- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
+- CONFIG_BOARD_LATE_INIT: Call board_late_init()
+- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
Configuration Settings:
-----------------------
used) must be put below this limit, unless "bootm_low"
enviroment variable is defined and non-zero. In such case
all data for the Linux kernel must be between "bootm_low"
- and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
+ and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
variable "bootm_mapsize" will override the value of
CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
then the value in "bootm_size" will be used instead.
This setting describes a second storage area of CONFIG_ENV_SIZE
size used to hold a redundant copy of the environment data, so
that there is a valid backup copy in case there is a power failure
- during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
+ during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
aligned to an erase block boundary.
- CONFIG_ENV_RANGE (optional):
- CONFIG_SYS_CCSRBAR_PHYS:
Physical address of CCSR. CCSR can be relocated to a new
physical address, if desired. In this case, this macro should
- be set to that address. Otherwise, it should be set to the
+ be set to that address. Otherwise, it should be set to the
same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
is typically relocated on 36-bit builds. It is recommended
that this macro be defined via the _HIGH and _LOW macros:
be used if available. These functions may be faster under some
conditions but may increase the binary size.
+Freescale QE/FMAN Firmware Support:
+-----------------------------------
+
+The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
+loading of "firmware", which is encoded in the QE firmware binary format.
+This firmware often needs to be loaded during U-Boot booting, so macros
+are used to identify the storage device (NOR flash, SPI, etc) and the address
+within that device.
+
+- CONFIG_SYS_QE_FMAN_FW_ADDR
+ The address in the storage device where the firmware is located. The
+ meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
+ is also specified.
+
+- CONFIG_SYS_QE_FMAN_FW_LENGTH
+ The maximum possible size of the firmware. The firmware binary format
+ has a field that specifies the actual size of the firmware, but it
+ might not be possible to read any part of the firmware unless some
+ local storage is allocated to hold the entire firmware first.
+
+- CONFIG_SYS_QE_FMAN_FW_IN_NOR
+ Specifies that QE/FMAN firmware is located in NOR flash, mapped as
+ normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
+ virtual address in NOR flash.
+
+- CONFIG_SYS_QE_FMAN_FW_IN_NAND
+ Specifies that QE/FMAN firmware is located in NAND flash.
+ CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
+
+- CONFIG_SYS_QE_FMAN_FW_IN_MMC
+ Specifies that QE/FMAN firmware is located on the primary SD/MMC
+ device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
+
+- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
+ Specifies that QE/FMAN firmware is located on the primary SPI
+ device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
+
+
Building the Software:
======================
make NAME_config
where "NAME_config" is the name of one of the existing configu-
-rations; see the main Makefile for supported names.
+rations; see boards.cfg for supported names.
Note: for some board special configuration names may exist; check if
additional information is available from the board vendor; for
steps:
1. Add a new configuration option for your board to the toplevel
- "Makefile" and to the "MAKEALL" script, using the existing
- entries as examples. Note that here and at many other places
- boards and other names are listed in alphabetical sort order. Please
- keep this order.
+ "boards.cfg" file, using the existing entries as examples.
+ Follow the instructions there to keep the boards in order.
2. Create a new directory to hold your board specific code. Add any
files you need. In your board directory, you will need at least
the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
run - run commands in an environment variable
bootm - boot application image from memory
bootp - boot image via network using BootP/TFTP protocol
+bootz - boot zImage from memory
tftpboot- boot image via network using TFTP protocol
and env variables "ipaddr" and "serverip"
(and eventually "gatewayip")
kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
bootm_mapsize.
- bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
+ bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
This variable is given as a hexadecimal number and it
defines the size of the memory region starting at base
address bootm_low that is accessible by the Linux kernel
fdt_high - if set this restricts the maximum address that the
flattened device tree will be copied into upon boot.
+ For example, if you have a system with 1 GB memory
+ at physical address 0x10000000, while Linux kernel
+ only recognizes the first 704 MB as low memory, you
+ may need to set fdt_high as 0x3C000000 to have the
+ device tree blob be copied to the maximum address
+ of the 704 MB low memory, so that Linux kernel can
+ access it during the boot procedure.
+
If this is set to the special value 0xFFFFFFFF then
the fdt will not be copied at all on boot. For this
to work it must reside in writable memory, have
add the information it needs into it, and the memory
must be accessible by the kernel.
+ fdtcontroladdr- if set this is the address of the control flattened
+ device tree used by U-Boot when CONFIG_OF_CONTROL is
+ defined.
+
i2cfast - (PPC405GP|PPC405EP only)
if set to 'y' configures Linux I2C driver for fast
mode (400kHZ). This environment variable is used in
boards currenlty use other variables for these purposes, and some
boards use these variables for other purposes.
-Image File Name RAM Address Flash Location
------ --------- ----------- --------------
-u-boot u-boot u-boot_addr_r u-boot_addr
-Linux kernel bootfile kernel_addr_r kernel_addr
-device tree blob fdtfile fdt_addr_r fdt_addr
-ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
+Image File Name RAM Address Flash Location
+----- --------- ----------- --------------
+u-boot u-boot u-boot_addr_r u-boot_addr
+Linux kernel bootfile kernel_addr_r kernel_addr
+device tree blob fdtfile fdt_addr_r fdt_addr
+ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
The following environment variables may be used and automatically
updated by the network boot commands ("bootp" and "rarpboot"),
is raised.
If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
-will be programmed into hardware as part of the initialization process. This
+will be programmed into hardware as part of the initialization process. This
may be skipped by setting the appropriate 'ethmacskip' environment variable.
The naming convention is as follows:
"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
useful when you configure U-Boot to use a real shell (hush)
as command interpreter.
+Booting the Linux zImage:
+-------------------------
+
+On some platforms, it's possible to boot Linux zImage. This is done
+using the "bootz" command. The syntax of "bootz" command is the same
+as the syntax of "bootm" command.
+
+Note, defining the CONFIG_SUPPORT_INITRD_RAW allows user to supply
+kernel with raw initrd images. The syntax is slightly different, the
+address of the initrd must be augmented by it's size, in the following
+format: "<initrd addres>:<initrd size>".
+
Standalone HOWTO:
=================