Dear Amandeep,
In message 3d083b80904211200h413b85dfv253e4990b9456741@mail.gmail.com you wrote:
Another question - How can I boot from this USB key. Can I put Debian 5.0 Lenny image on USB key and boot AT91SAM9263-EK from there? If yes, how would I do it? I am new to Linux. Many thanks for your help.
You can do this but you better try to understand what you are doing first. A USB stick is not a harddisk drive, and a standard distribution like Debian Lenny is NOT made for use on devices (like USB sticks) that have only a limited number of write cycles per block.
At least you should study carefully what others are doing and tweak system behaviour to minimize the number of write operations to the root file system (start looking at things like the "noatime" mount options, etc.).
Then you will notice that you have to make the kernel wait for the root device (the USB stick) to become ready - normally the kernel will try to mount the root file system long before the USB mass storage devices have been initialized. There are several ways around to acchive this - look around.
Note that all these things are (1) advanced topics for embedded systems [so you probably want to consult an expert], and they are (2) completely off topic on this U-Boot mailing list.
Best regards,
Wolfgang Denk