It is not possible to boot directly from USB memory stick. You are able to program a blank device via USB though using a PC-based tool (like the Manufacturing Tool for example).
You could organize your boot so that linux kernel is started from small SPI flash which would then mount the root file system from USB stick and continue booting from there...
Vladan
Thanks for the explanation on USB booting. I saw in the documentation about booting from USB and I assumed you could do it as a mass storage device. The documentation is not very clear on what they mean by USB booting, but it looks like it is only supported in Windows as I did not see any mention of Linux in the docs.
As far as mounting the USB stick on the EVK, I do see the USB core is loading in the kernel so I think the stock demo SD card has support for USB but maybe not the mass storage device driver or the FAT file system. I will have to look into it more. Thanks.