Lots of useful info on how to compile your own kernel, build your own u-boot, use the usb-otg utils to 'unbrick' your board.
http://www.eewiki.net/display/linuxonarm/i.MX6x+SABRE+Lite
note that if you go this route to get a mainline linux kernel with devicetree enabled then you won't get video for now. This isn't unusual since the video drivers tend to have a tough time getting into the upstream kernels.