AMD Releases Open-Source R600/700 3D Code

Since earlier this year we have been waiting for AMD to release documentation and/or code on the ATI R600 series concerning 3D acceleration so that the open-source Linux drivers can begin to support the newer ATI graphics processors. It has taken longer than expected for AMD to complete and release this information, but it's now available. AMD has released the fundamental Linux code needed to begin fostering the development of an open-source R600 3D driver. Furthermore, this code also concerns the latest R700 series of graphics processors! The microcode for the newest GPUs has also been released.

Just hours before the start of

href="http://www.phoronix.com/scan.php?page=search&q=FOSDEM+2008">FOSDEM 2008in late February, AMD had released theirR500 3D programming documentation. This documentation paved the way for open-source developers to begin working on aMesadriver that would extend the earlier R300/400 series support to enable OpenGL acceleration on the Radeon X1000 series. This was also the first public documentation drop concerning 3D support sinceAMD's open-source strategy announcementlast September. Following the 3D documentation release, two revisions were made to add in more technical details. The first revision added in

href="http://www.phoronix.com/scan.php?page=news_item&px=NjM2NA">just four pageswhile the second had

href="http://www.phoronix.com/scan.php?page=news_item&px=NjQxMg">detailed their command processor.

Up to that point all of the work was going into enabling mode-setting support and other basic functionality across the R500 and R600 series in the

href="http://www.phoronix.com/scan.php?page=search&q=xf86-video-radeonhd">xf86-video-radeonhddriver (and then

href="http://www.phoronix.com/scan.php?page=search&q=xf86-video-ati">xf86-video-atithroughAtomBIOS). Right after they announced their open-source initiative they had released

href="http://www.phoronix.com/scan.php?page=news_item&px=NjA1Mw">900 pages of specificationsand then in the months that followed they released alot

href="http://www.phoronix.com/scan.php?page=news_item&px=NjUyMA">more

documentation.

Two weeks after the initial R500 3D documentation release, AMD had released anR300 3D register guide. This programming guide concerning their older graphics hardware was previously only available through Non-Disclosure Agreements to select developers. AMD had alsoreleased microcode for all their GPUsfrom their proprietary Catalyst driver.

Less than a month after the R500 3D documentation drop, the first milestone was reached:hardware-accelerated R500 glxgears. This was quite a milestone and signaled that OpenGL acceleration for the R500 series in Mesa would soon be coming. In late May there was thenopen-source R500 3D successwithCompizbeginning to work on this relatively modern hardware along with some other OpenGL programs. As we shared in an article a day later, it was possible togame with the open-source driverusing some select titles that don't stress Mesa too much. Since the point of reaching parity in the open-source support to that of earlier ATI generations, the rest of the year has not been too exciting.

Novell, AMD, and Red Hat developers have been doing a majority of the work taking advantage of the documentation, while internally at AMD they have been working to prepare the R600 documentation for release.John BridgmanandAlex Deucherhave been working on deciding what code or documentation is needed for programming, sanitize it of any information not relevant to bringing up the 3D engine, remove any details concerning future ATI hardware, and then getting all of this work cleared by AMD's lead software and hardware architects so that it can be publicly released without any NDAs or other string attached. To say the least, this has taken longer than anticipated. There were a few times when it looked like the documentation and code would be coming soon, only to then be pushed back by additional hurdles, but this time around they got code to deliver too. Part of the good news out of this though is that they are continuing to refine their documentation writing process so that with future generations there may be a quicker turn-around time.

The other good news is that with the R600 series they made sure there was sufficient documentation coverage by first writing the software support to find out what was needed, instead of finding out later they hadn't released enough documentation to enable the 3D engine or they ended up releasing too much documentation than what most open-source developers would actually use. The code they are releasing is in a working state, but is currently meant for developer usage.

News Source : AMD Releases Open-Source R600/700 3D Code