There's a
thread on the Rockbox forums and mostly complete build instructions on my
github repo. The only thing that's missing from the build instructions is how to build the bootloader: you need to clone the Rockbox repo and apply
this patch manually (if you've not used Gerrit before, click the "Download" button that's right above the diffstat). If the patch says merged, it's already in the repo, there's no need to manually apply it.Then follow the
development guide to get your build environment set up and compile the Q1 bootloader. You then need to compile "jztool" found in utils/jztool, you can use that to either flash the bootloader or just temporarily load it. Either way is good enough for running Linux.
Unfortunately the documentation is kind of poor and all over the place. If you get stuck just ask on the forums or thru IRC on #rockbox on liberachat. Although I'm not on IRC regularly I do read the logs.
Good luck! And if you do have the time to lend a hand, that would be very welcome.