The radeonhd driver, or xf86-video-radeonhd is an X.org video driver for R500 and newer ATI graphics devices.
It is being developed by Novell for AMD, with the free documentation provided by AMD.
The driver supports full modesetting (read: any mode is usable, not only those provided by the
... [More] BIOS), which is backwards compatible to RandR 1.2. Future work is happening especially on more advanced features like 2D, 3D and video acceleration. [Less]
Some of the radeon HD video cards are not supported by apple's native drivers yet. Here is an effort to make an workable framebuffer driver for these cards by either borrowing apple's codes or porting the codes from Linux open-source drivers.