ATI Rage 128
Status
The ATI Rage128 desktop and mobility chips are supported by the DRI. EricAnholt recently added pageflipping support. You can enable pageflipping by adding this to your config:
Option "EnablePageFlip" "true"
It will give you a small boost in performance, but it causes problems for some people.
There is no support for suspend/resume for r128. It shouldn't be too hard to add support. Take a look at the radeon suspend/resume code. I think Xv also needs some fixes for suspend/resume.
Todo: implement hardware-accelerated projective texturing
Specifications
The register documentation is available on Wikipedia
http://en.wikipedia.org/wiki/Rage_128