U-Boot - usage and documentation by Ulf Samuelsson. -
- --
-
- About U-Boot -
- Board Support for AT91RM9200DK -
- Board Support for AT91RM9200EK -
- Board Support for AT91SAM9G20EK -
- X-Modem/Raw extensions to minicom -
- New Command: factory -
- New Command: os -
- New Command: fs -
- New Command: setargs -
- New Command: led -
- New Command: mux -
- New Command: ethinit -
- Special environment variables -
About U-boot
- [TOP] - -- U-Boot is an open source bootloader ported to a multitude of processors. - See (U-Boot Home) - for documentation for vanilla U-Boot. This document only describes - changes compared to the vanilla u-boot. -
- -Board support for at91rm9200dk
- [TOP] - -- "at91rm9200dk" is updated to use a linux like API for gpio. - A new target "at91rm9200dk_df" is defined to support boot from dataflash. -
- -Board support for at91rm9200ek
- [TOP] - -- The "at91rm9200ek" BSP supports booting from a parallel flash. - The "at91rm9200df" BSP supports a generic target booting from dataflash. -
- -Board support for at91sam9g20ek
- [TOP] - -- The "at91sam9g20ek" target with dataflash(card) and NAND boot support. -
- -Minicom extensions
- [TOP] - -- "sx-at91" is a reliable X-Modem application allowing download to the at91rm9200 - based board -
-- "raw-at91" is a download application which will download binary data using minicom. - Typically used to download an environment script. -
- -New command: factory
- [TOP] - --
factory
-
-
- - "factory" will set a selected set of environment variables - back to the compile time default. The following will give some - hints on capabilities, but is not yet complete. -
- -- It will generate a set of scripts which will facilitate downloading - the kernel and root file system using tftp and will also - add commands to store into and retrieve from flash -
- -New command: os
- [TOP] - --
os
-
-
- "os" computes a new name for the linux kernel -
- -New command: fs
- [TOP] - --
fs
-
-
- "fs" computes a new name for the file system -
- -New command: setargs
- [TOP] --
setargs
-
-
- "setargs" will create new bootcmd/bootargs combination from - kernel name, filesystem name, and rootfs type. -
- -New command: led
- [TOP] - --
led [green | yellow | red | all ] [ on | off ]
-
-
-
- "led" will turn on or off the specified (coloured) led -
- -New command: mux
- [TOP] - --
mux [spi | mmc ]
-
-
-
- "mux" will select how to use the flash card connector on the - at91rm9200dk or at91rm9200ek -
- -New command: ethinit
- [TOP] - --
ethinit
-
-
-
- "ethinit" can be used to delay the boot of linux, until a valid network - connection has been established. This is useful if the machine is NFS mounting - the root file system and both this machine and the NFS server are powering up - simultaneously. The NFS server could take a lot longer to boot, and waiting - for this to boot may be neccessary for proper operation. -
- -Special environment variables
- [TOP] - --
rd
-
-
- rd contains the name of the current root file system
- It is autmatically generated from
-
ver
-
-
- You can handle a number of different root fs by defining ver
.
- When running fs
rd will be assigned from one of:
-
rd-1, rd2, rd-3 ...
- By defining ver
to a number you will
- select the appropriate disk name
-
-
fs-date
-
-
- "date" part of the root file system name -
- --
linux
-
-
- linux contains the name of the current kernel. -
-
- It is generated from several environment variables when os
is run
-
- A typical name would be "at91sam9263ek-linux-2.6.28-20090105.gz" -
- --
hostname
-
-
- "name" part of the kernel file name -
- --
kernel-version
-
-
- "version" part of the kernel file name -
- --
kernel-date
-
-
- "date" part of the kernel file name -
- --
fstype [ ram | flash ]
-
- You can have several file system types. - bootargs is created depending on fstype.. -
- - [TOP] - -