libdrm is compiling, and I've got libdri and a DRI-converted r128 driver that need to be made to compile now. For now it's almost all just direct copies of XFree86 code (sometimes with bits chopped out). I know there's a lot more compatibility junk we can remove, but the first thing is to get some drivers working.
As a quick explanation of these parts: libdrm is a userland API for talking to the DRM. libdri includes both the DRI* API and the XF86DRI extension. However, this does not mean "DRI in kdrive" yet as people might think -- we need GLX and I'm sure a lot more work on libdri before we can have hardware-accelerated 3d.
DRI:
Nobody's stepping up to do the creation of a lower-level kernel driver for the DRM and framebuffer to share (as far as resource allocation, perhaps DMA/IRQ handling) on Linux. It really needs to happen, and Linus and many others agree. Unfortunately, there are very few people who want to work on this sort of stuff, so I may end up having to do it myself. I think my track record on my last commits to the Linux DRM should warn a real Linux kernel hacker to do it first. :-P