1 1.1 mrg This is a historical description of what is now the kgsl backend 2 1.1 mrg in libdrm freedreno (before the upstream drm/msm driver). Note 3 1.1 mrg that the kgsl backend requires the "kgsl-drm" shim driver, which 4 1.1 mrg usually is in disrepair (QCOM does not build it for android), and 5 1.1 mrg due to random differences between different downstream android 6 1.1 mrg kernel branches it may or may not work. So YMMV. 7 1.1 mrg 8 1.1 mrg Original README: 9 1.1 mrg ---------------- 10 1.1 mrg 11 1.1 mrg Note that current msm kernel driver is a bit strange. It provides a 12 1.1 mrg DRM interface for GEM, which is basically sufficient to have DRI2 13 1.1 mrg working. But it does not provide KMS. And interface to 2d and 3d 14 1.1 mrg cores is via different other devices (/dev/kgsl-*). This is not 15 1.1 mrg quite how I'd write a DRM driver, but at this stage it is useful for 16 1.1 mrg xf86-video-freedreno and fdre (and eventual gallium driver) to be 17 1.1 mrg able to work on existing kernel driver from QCOM, to allow to 18 1.1 mrg capture cmdstream dumps from the binary blob drivers without having 19 1.1 mrg to reboot. So libdrm_freedreno attempts to hide most of the crazy. 20 1.1 mrg The intention is that when there is a proper kernel driver, it will 21 1.1 mrg be mostly just changes in libdrm_freedreno to adapt the gallium 22 1.1 mrg driver and xf86-video-freedreno (ignoring the fbdev->KMS changes). 23 1.1 mrg 24 1.1 mrg So don't look at freedreno as an example of how to write a libdrm 25 1.1 mrg module or a DRM driver.. it is just an attempt to paper over a non- 26 1.1 mrg standard kernel driver architecture. 27
Indexes created Mon Oct 26 00:26:21 UTC 2026