19bd392adSmrgThis is a historical description of what is now the kgsl backend
29bd392adSmrgin libdrm freedreno (before the upstream drm/msm driver).  Note
39bd392adSmrgthat the kgsl backend requires the "kgsl-drm" shim driver, which
49bd392adSmrgusually is in disrepair (QCOM does not build it for android), and
59bd392adSmrgdue to random differences between different downstream android
69bd392adSmrgkernel branches it may or may not work.  So YMMV.
79bd392adSmrg
89bd392adSmrgOriginal README:
99bd392adSmrg----------------
109bd392adSmrg
119bd392adSmrgNote that current msm kernel driver is a bit strange.  It provides a
129bd392adSmrgDRM interface for GEM, which is basically sufficient to have DRI2
139bd392adSmrgworking.  But it does not provide KMS.  And interface to 2d and 3d
149bd392adSmrgcores is via different other devices (/dev/kgsl-*).  This is not
159bd392adSmrgquite how I'd write a DRM driver, but at this stage it is useful for
169bd392adSmrgxf86-video-freedreno and fdre (and eventual gallium driver) to be
179bd392adSmrgable to work on existing kernel driver from QCOM, to allow to
189bd392adSmrgcapture cmdstream dumps from the binary blob drivers without having
199bd392adSmrgto reboot.  So libdrm_freedreno attempts to hide most of the crazy.
209bd392adSmrgThe intention is that when there is a proper kernel driver, it will
219bd392adSmrgbe mostly just changes in libdrm_freedreno to adapt the gallium
229bd392adSmrgdriver and xf86-video-freedreno (ignoring the fbdev->KMS changes).
239bd392adSmrg
249bd392adSmrgSo don't look at freedreno as an example of how to write a libdrm
259bd392adSmrgmodule or a DRM driver.. it is just an attempt to paper over a non-
269bd392adSmrgstandard kernel driver architecture.
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