Starting off the X.Org talks at FOSDEM 2008 was AMD's John Bridgman, who has been leading the AMD GPG open-source efforts. John had talked briefly about the history of their open-source efforts for the R500+ series and the evolution of AMD GPU hardware. Among the interesting comments made were that TexturedVideo/X-Video support for the R500/600 may be coming quite soon, DRM and Mesa work forthcoming, open-source multi-GPU multi-GPU support is on the road-map, and they will be re-releasing R200 programming documents. The RV620 and RV635 documentation is expected in the near future.
Below are some of the most interesting comments made during John Bridgman's talk:
- Information covering the RV620 and RV635 (Radeon HD 3400 to 3600 series) will be out soon. The Novell developers have received this RV630/635 documentation last month.
- The R200 programming guide covering the early Radeon 9000 components will be re-released. The information earlier than R300 hardware is harder to find internally, so the biggest problem is just finding an editable copy of this information. With that said, for the vintage ATI hardware it's more about answering questions and fixing things where with the R300 series and later they are focused on providing the documentation.
- The forthcoming RS780 (DirectX 10 IGP part) eliminates the 2D engine completely on the IGP front.
- Past the RS780 (Radeon HD 4000+) will eliminate any emulation support for the 2D command processor calls.
- John confirmed to the public that the R600 3D information should be out soon. The R600 3D update had significant changes, the VAP was replaced with VGT, new blocks to manage recirculation of graphics data through shader, backend hardware changes, and more memory management changes.
- Temperature sensor support is coming through LM_Sensors.
- Fan controller started with the RV630 is integrated and hopefully its AIBs will use that for future products. For earlier graphics cards, fan speed monitoring may come with trial and error since they can't release customer information (which company is using what fan controller externally). Power management is becoming a priority.
- Along with the forthcoming RV620/635 support the RS780 support is also coming around the same-time. Like we've previously mentioned, this support will come in two stages with the first stage being analog/digital interface support and later on will be the DisplayPort support.
- John and Alex are working to extract documentation on PowerPlay (ATI GPU power management) to the open-source community. There are no intellectual property concerns, but it's a matter of tracking down all of the needed information.
- While there's been three open-source drivers that support the R500 series (Avivo, Radeon, RadeonHD), it's not the right thing to do for DRM and Mesa. John doesn't want to see multiple DRM and Mesa implementations.
- On the matter of Radeon vs. RadeonHD, in the end (as you would expect) they will settle on one code-base.
- A next-generation Unified Video Decoder (UVD) can be found on the RS780+ GPUs, which on the slide was shown as UVD2.
- Compute Abstraction Layer is their next GPGPU API. Right now it only supports Windows but Linux is a priority.
- There should be enough information for those interested in writing 3D compute drivers for CAL.
- Multi-GPU support! There is some sort of multi-GPU support that will be worked on due to more Linux users picking up the new Radeon HD 3870X2.
- Alex Deucher has TexturedVideo working on the R300 series, so running X-Video on the R500 and R600 looks promising "real soon now", according to this presentation.
- The fglrx driver is 28 million lines of code. Takes a while to clean-up for the bottom-end of the driver to be released.
- AMD is looking at a possibility of a Linux hybrid driver. This would consist of some fglrx components being open-sourced. This has been discussed quite extensively (with comments from John himself) in the Phoronix Forums.
More information is coming soon and share your thoughts or questions in the Phoronix Forums.