Debian/X.org notes - Why some X drivers like firmware-linux - Brice Goglin's Blog
May. 11th, 2009
09:07 - Debian/X.org notes - Why some X drivers like firmware-linux
We got many bug reports about X being slow. Many of them are caused by some MTRR/PAT problems in kernel 2.6.29. But some are not.
It appears to be caused by Debian 2.6.29 kernels not containing ugly binary graphics firmware anymore. Indeed, radeon, r128 and mga driver need a firmware for 3D, but also for some 2D and Xv features (basically everything that's hardware accelerated). So if you use one of these X drivers and you have some problems, a quick look in the kernel logs might tell you that a firmware is missing. Installing the firmware-linux package may help then. We are adding the corresponding Suggests line to X drivers.
Moreover, some people are upgrading to 2.6.30 pre-release because it contains DRM support for R600 boards. A ugly binary firmware is needed as well and it has obviously been removed from Debian 2.6.30 experimental packages. But firmware-linux does not seem to contain this firmware yet. So if you want 2.6.30 for R600 DRM, you want to either build your own 2.6.30 kernel, or wait for an updated firmware-linux package to be available with R600 firmware. See bug#523467 for an example.