| This is a historical discription of what is now the kgsl backend |
| in libdrm freedreno (before the upstream drm/msm driver). Note |
| that the kgsl backend requires the "kgsl-drm" shim driver, which |
| usually is in disrepair (QCOM does not build it for android), and |
| due to random differences between different downstream android |
| kernel branches it may or may not work. So YMMV. |
| |
| Original README: |
| ---------------- |
| |
| Note that current msm kernel driver is a bit strange. It provides a |
| DRM interface for GEM, which is basically sufficient to have DRI2 |
| working. But it does not provide KMS. And interface to 2d and 3d |
| cores is via different other devices (/dev/kgsl-*). This is not |
| quite how I'd write a DRM driver, but at this stage it is useful for |
| xf86-video-freedreno and fdre (and eventual gallium driver) to be |
| able to work on existing kernel driver from QCOM, to allow to |
| capture cmdstream dumps from the binary blob drivers without having |
| to reboot. So libdrm_freedreno attempts to hide most of the crazy. |
| The intention is that when there is a proper kernel driver, it will |
| be mostly just changes in libdrm_freedreno to adapt the gallium |
| driver and xf86-video-freedreno (ignoring the fbdev->KMS changes). |
| |
| So don't look at freedreno as an example of how to write a libdrm |
| module or a DRM driver.. it is just an attempt to paper over a non- |
| standard kernel driver architecture. |
