Killing DRM Graphics Cruft With Fire

It seems to be a good time to clean-up the Linux graphics driver stack. After old hardware support was dropped in Mesa in August, more Mesa code was dropped, and most recently the classic ATI R300/R600 drivers are to be killed (this is set to happen this Friday). Now Intel's Daniel Vetter is chopping up some DRM code.

Daniel Vetter, one of Intel's newest OSTC employees working on the Linux graphics stack (he just officially joined in September but has been around for a bit longer than that in the Linux world), has pushed 23 patches to the DRI mailing list that would remove more than 1,000 lines of code from the DRM area of the Linux kernel tree. Those affected by this "kill drm cruft with fire" action will largely be VIA and SiS. It's about removing old code from DRM.

Daniel's patch-set completely kills off "drm_sman", which was a simple memory manager interface for DRM that was created by Thomas Hellström during the Tungsten Graphics days (2006). The VIA and SiS DRM components are now using drm_mm instead of drm_sman, plus have received minor other reworks. Even the DRM Savage driver has received a few tiny tweaks. This is sadly the most work these ancient and largely unsupported drivers have received in a while, even though these patches today aren't really significant and just "cleaning the house."

DMA queue support has also been dropped in Daniel's patches since the support is now unused. Also killed off is the procfs (/proc/dri) support for DRM, since debugfs and sysfs interfaces have already been around for years and are the primary targets.

Daniel's patches begin here.