Building U-Boot
---------------
-Note: There are currently six variants of the TX51 module, that
+Note: There are currently three variants of the TX51 module, that
require slightly different U-Boot configurations. They are
- distinguished through the first and last digit of the module
- name suffix. Replace the '?' in the following description with
- the corresponding numbers from your TX51 module.
- E.g. TX51-8021 => 'make tx51-8xx1_config'
+ distinguished through the last digit of the module name
+ suffix. The configuration names depending on the last digit of
+ the module name are:
+ TX51-8??0 tx51-8xx0_config
+ TX51-8??1 tx51-8xx1_2_config
+ TX51-8??2 tx51-8xx1_2_config
+
Unpacking the source
--------------------
tar -xjf /cdrom/U-Boot/u-boot-src.tar.bz2
Alternatively you can access the current source via the git repository:
-git://git.kernelconcepts.de/karo-tx-uboot.git master
+git://git.karo-electronics.de/karo-tx-uboot.git master
Compiling U-Boot
----------------
export ARCH=arm
export CROSS_COMPILE=arm-cortexa8-linux-gnueabi-
-make tx51-?xx?_config (see above Note!)
+make tx51-8xx?_config (see above Note!)
make
---------------
Environment variables:
+boot_mode selects which boot script will be used by 'bootcmd' to
+ boot the application (Linux)
+ supported values:
+ nand: (default) load kernel from NAND partition 'linux'
+ and mount rootfs (fstype UBIFS)
+ from partition 'rootfs'.
+ mmc: load kernel from file 'uImage' on first
+ partition (FAT) on (first) SD/MMC card
+ and mount rootfs (fstype autodetected)
+ from second partition.
+ net: load kernel image via tftp (file uImage)
+ and mount rootfs via NFS. This requires
+ the additional variables 'nfsroot'
+ (path to rootfs on NFS server) and
+ 'nfs_server' (hostname or IP address of
+ NFS server) to be set.
+ jffs2: (legacy) load kernel from NAND partition 'linux'
+ and mount rootfs (fstype JFFS2)
+ from partition 'rootfs'.
+
+cpu_clk <CPU freq [MHz]> CPU clock frequency set after boot.
+
+touchpanel {tsc2007|edt-ft5x06} type of touchpanel.
+ No touchpanel will be enabled when unset.
+
+otg_mode [host|device|none] operation mode of the USBOTG port
+
+video_mode <one of the display names from the Glyn Family Concept or
+ a video mode as understood by Linux fb_find_mode() function
+ (e.g.: 640x480MR-24@60)>
+ LCD interface will be disabled when unset.
-cpu_clk <CPU freq [MHz]>
-touchpanel {tsc2007|edt-ft5x06}
-otg_mode [host|device|none]
-video_mode <video mode as understood by Linux fb_find_mode() function>
- e.g.: VGA-1:640x480MR-24@60
baseboard {stk5-v3|stk5-v5} selects type of baseboard
- 'stk5-v5' setting disables USB Host mode on USBOTG port.
- strings not starting in 'stk5' prevent the STK5 specific
+ 'stk5-v5' setting disables USB Host mode on USBOTG port
+ and redefines the LCD0 pin as CAN transceiver control pin.
+ Strings not starting in 'stk5' prevent the STK5 specific
pad initialization to be done.
+
splashimage either: memory address (e.g. ${loadaddr}) of a BMP file
to be displayed instead of the built-in logo. Since NAND
flash is not accessible in a memory mapped fashion,
Note: Some variables (like 'cpu_clk' or 'splashimage') may render the
board unbootable if incorrectly set. Therefore these variables
will not be evaluated in case the board has been reset through a
- watchdog reset or a character is available on the serial console
+ watchdog reset or <CTRL-C> is detected on the serial console
during startup to give the user a chance to recover from this
- situation.
+ situation. You should press and hold <CTRL-C> before applying
+ power to the module, for this to work.