While AMD has published open-source Radeon GPU driver code for modern graphics processors up through the latest Sea Islands
parts, they have fallen behind on publishing 3D GPU programming specifications and programming guides for the more modern hardware. Fortunately, they have now caught up.
AMD's Alex Deucher announced today via his personal blog
that programming guides and register specifications on the 3D engines for the Evergreen, Northern Islands, Southern Islands, and Sea Islands GPUs is now in the NDA-free public domain. These parts represent the 3D engines on the Radeon HD 5000 through Radeon HD 8000 series graphics processors.
It's great to see AMD's public documentation finally catch up with their latest code. The Radeon HD 5000 "Evergreen" and Radeon HD 6000 "Northern Islands" open-source driver support is in good shape while the Southern Islands and Sea Islands open-source driver support is still very much a work-in-progress via the new RadeonSI
Gallium3D driver, as has been covered by numerous Phoronix articles up to this point.
As was already noted, AMD has also released new HDA GPU audio programming details