There is a fully functional unichrome DRM on top of TTM, that together with the 3D driver in mesa's openchrome branch worked like a charm (even outperformed Intel's i965 with identical CPU at the time). Problem was that it was not backwards compatible with via's old drm.
It should serve as a good starting point though, if I can remember where I put it....
I have a copy of your work already and yes I had to foward port it since the TTM api changed quite a bit from when you wrote that code.