Following the release of xf86-video-ati 6.7.197 just moments ago, David Airlie has merged the AtomBIOS support branch back to the xf86-video-ati master branch. What this means is that the Radeon X1000 (R500) and HD 2000 (R600) support (even with the Radeon HD 2900XT) is now in the mainline Radeon driver and when using git you no longer need to switch to this separate branch and will be included in the ATI 6.7.198 driver release and later.
All the OSS developers talk to each other pretty much every day on IRC, so I don't think there are any surprises here and certainly no jumping out of buildings.
Radeonhd is a smaller, newer code base with the SuSE guys working full time supporting end users and polishing the details. The radeon code base has been around for a long time (although substantially re-written for randr1.2) so already has 2d and 3d acceleration code for earlier generations of ASICs -- and the 2d acceleration has been ported to run on 5xx.
We will probably use the radeon code base as the basis for releasing sample 3d code simply because the rest of the 3d framework is already in place, but at the same time we are continuing to partner with the radeonhd developers to continue developing the radeonhd code.
I know it's fun to look at these things as competitions with winners and losers, but I don't think it's going to work out that way. Changes and ideas are already moving back and forth between the code bases and I expect that will continue for a while. There are some different design philosophies between the groups, and I expect it will take a while for everyone to agree on a common ground (and, hence, a common code base). My prediction is that it will take...
... two open source conferences, two more RandR revisions, and 57 liters of beer.
radeonhd is dedicated to >=r5xx chips and thus is more tuned to this hardware. separate driver for >=r500 cards only might turn out to be better, performance-wise in the future. (usually less generic driver is more optimized for targeted hardware). it's developers turned out to be fairly competent folks, who know what they're doing.
on the other hand, radeon driver is more generic, supporting a wider range of cards and it's fairly easy to add support for new cards (as shown by atombios merge). however constantly extending the driver by supporting more and more hardware might make the codebase too complex and discourage people who would like to join the development.
radeonhd developers have pretty good grip on r5xx/r6xx hardware by now, while radeon devs have good knowledge of older chips, backed by their experience and knowledge of various quirks (something that specs might not cover). since there are similarities between these cards, both teams will benefit from each other's experiences.
it's better to have two projects. maybe there'll be a merge between them in the end, maybe not. it's a win-win situation anyway, as nobody is losing here.
I do have a question. I'd like to give this a try so I pulled the latest from git, the files are on the local machine and autogen, make and make install ran with no unexpected errors. Easy as cake.
I have an R580+ on Ubuntu 7.10. What driver should I specify in xorg.conf, "ati" or "radeon"?
I think I remember seeing somewhere that "ati" is the correct string and that the driver will figure out the components required to support the hardware, but I can't find it to verify and I'm at a stage where I don't trust my memory so much.