1.Change linux kernel image zImage to zImage.img.

mkimage -n 'nicholas' -A arm -O linux -T kernel -C none -a 0x30008000 -e 0x30008040 -d zImage zImage.img

There is a information head in zImage.img used to recognised by u-boot.

2.Download to RAM of embedded board. I use tftp this time.

Put zImage.img to tftp server dirctory.

Type command in embedded board:

tftpboot 0x30008000 192.168.0.100:zImage.img

3.Boot from RAM.

bootm 30008000

4.About tftp server, look another article of mine:

http://log.anycle.com/skill/251.html