RadeonHD Driver Introduces Major Changes, RV620/635 Support

Following a period of relative inactivity in the xf86-video-radeonhd git tree over the past few weeks, this afternoon Novell's Egbert Eich had pushed forward 55 changes to this open-source R500/600 driver. The AMD Radeon HD 3400 and 3600 series are now supported and there are a number of other significant changes. The RV620/635 mode-setting support has required the most significant work since the R500 series, since all output blocks have been altered due to the introduced DisplayPort capabilities. We have already tested out this latest code and were left with a positive impression.

While the immediate result from these 55 commits are RV620 and RV635 (Radeon HD 3400/3600) support, there is much more underlying work that has went on. In fact, the code from these 55 commits is equivalent to a 7,208 line patch. Among the work that has gone on is splitting up encoders and transmitters and completely reworking the digital outputs and significant alterations to analog outputs. The digital outputs have changed entirely in order to be more flexible and will eventually allow for DisplayPort capabilities. DisplayPort is the forthcoming digital display interface standard that's backed by VESA and is meant to be the royalty-free and license-free competition to HDMI. DisplayPort connectors first appeared on some Radeon HD 3400 and 3600 graphics cards and most recently is appearing on some AMD 780G-based motherboards. In addition, support for dual-link DVI displays has been introduced.

AtomBIOS is now used by the RadeonHD driver. Well, partially... AtomBIOS is currently being used for the Uniphy transmitter. The Uniphy transmitter is one of the additions with the Radeon HD 3400/3600 graphics processors. On the new 780G Chipset this transmitter is changed and known as PCIEPHY. Support for the AMD 780G motherboard chipset, which is equivalent to being a Radeon HD 3200 IGP, isn't yet supported by this latest RadeonHD work but it's next up on their agenda.

Does this mean RadeonHD 1.2? RadeonHD 1.1 was released back in December and is now vastly outdated, but this work made public today isn't exactly version 1.2. The next release should come once this code has been in the public spotlight for a while and has received public feedback of any issues. In the future, RadeonHD developers may be pushing out releases more often.

Some of the other work that has went into these RadeonHD improvements impact TV-Out support. However, don't go connect your Radeon R500/600 graphics card to your TV just yet. The TV-related commits to this point include adding TV detection, parsing of TV data tables in AtomBIOS, adding AtomBIOS support for setting up the TV encoder, an option to pass the TV standard, and monitor support for TVs. Egbert Eich had mentioned that the work left to do for RadeonHD TV-Out support is just putting all of these pieces together. This TV-Out support may come within the next couple of weeks.

Contained in this work today is also implementing hardware-level scaling code. However, the framework for enabling scaling isn't yet accomplished. It's expected that this framework will be a pre-requisite when working on the TV-Out support. For now this hardware-level scaling code will fix some mode-setting issues.

In addition to the RS780 support being on Novell's near-term roadmap, they will also be exploring the DDIA for the RS690. DDIA is the now infamous TMDS block found on the RS690 IGP that the xf86-video-radeonhd developers had found that previously wasn't mentioned by AMD as they didn't believe it was in use. Since then, the Novell developers have received register specifications for DDIA.

While the major end-user feature of these 55 commits is the Radeon HD 3400/3600 support, all Radeon R500/600 owners are encouraged to test out the latest xf86-video-radeonhd code. Nor is the information we have covered in this article all-inclusive of the 55 commits and thousands of lines of code that make up this recent activity. We have been testing out this code for a few hours prior to its public introduction, and even when using a Radeon HD 3650 512MB we have been greeted by success. If you are an R500/600 owner, be sure to check out the xf86-video-radeonhd driver in the coming days!