I have copied documentation about the flight software from both the Golf SVN and from the Golf redmine wiki and placed them in the pacsat reference repo under "Golf". This include Golf Driver Documentation and Golf Flight Software Description. Both are reasonably up to date, although the flight software has a lot of Golf stuff that is not relevant. However it does talk about how various RTOS primitives are used and the general scheme of how it is put together.
This is all on github under AMSAT-NA/pacsat/reference/Golf.
Burns Fisher, WB1FJ *AMSAT(R) Engineering -- Flight Software*