Pre-requisites:
- An TFTP server
- U-boot with TFTP capabilities
If you need to run a script (for example, running multiple setenv's commands) in U-boot for many boards, you can instead create a U-boot script (called script image), place it into your tftp folder, then ask U-boot to fetch it and run it. For example, you want to run the following setenv instructions
setenv loadaddr 0x10800000
setenv bootargs_base 'setenv bootargs console=ttymxc0,115200'
setenv bootargs_mmc 'setenv bootargs ${bootargs} root=/dev/mmcblk0p1 rootwait rw video=mxcfb0:dev=ldb,LDB-XGA,if=RGB666'
setenv bootcmd_mmc 'run bootargs_base bootargs_mmc;mmc dev 3;mmc read ${loadaddr} 0x800 0x2000;bootm'
run bootcmd_mmc
save it into a file, I choose the name 'myscript'; under your <U-boot folder>/tools, execute
$ mkimage -T script -C none -n 'My Script' -d myscript myscript.img
and copy myscript.img file into your TFTP folder.
On the target, set the following two variables (serverip and bootcmd)
# Set the Server IP, where the TFTP server is running
setenv serverip <the server IP> # In case the server IP is static, you can place this line into the U-boot script
setenv scriptaddr 0x10700000
setenv scriptname myscript.img
# You can use either TFTP or DHCP
setenv tftpcmd tftp # or 'dhcp' in case you want to use dhcp U-boot command
# Not needed for dhcp
setenv ipaddr <the target IP> # needed in case the command tftp is used
setenv gatewayip <the Gateway IP> # needed in case the command tftp is used
setenv bootcmd '${tftpcmd} ${scriptaddr} ${scriptname}; source ${scriptaddr}'
saveenv
reset
That is all you need to do.
Enjoy U-booting!
