How to interact bootloader with Linux host

Hi, friends,

The user manual on how to download kernel to mini2440 is using Windows as
the host. I am using Linux as the host, how to download kernel to the
board? Is there USB driver provided for Linux?
Since Supervivi is not open source, I have no idea how the board and the
host interact when downloading image via USB.

http://www.friendlyarm.net/dl.php?file=usbpush.zip

Thanks a lot!