2018-12-19 07:55:45 -07:00
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This is a historical description of what is now the kgsl backend
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2016-07-20 11:11:58 -06:00
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in libdrm freedreno (before the upstream drm/msm driver). Note
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that the kgsl backend requires the "kgsl-drm" shim driver, which
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usually is in disrepair (QCOM does not build it for android), and
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due to random differences between different downstream android
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kernel branches it may or may not work. So YMMV.
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Original README:
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----------------
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2012-10-07 17:57:31 -06:00
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Note that current msm kernel driver is a bit strange. It provides a
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DRM interface for GEM, which is basically sufficient to have DRI2
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working. But it does not provide KMS. And interface to 2d and 3d
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cores is via different other devices (/dev/kgsl-*). This is not
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quite how I'd write a DRM driver, but at this stage it is useful for
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xf86-video-freedreno and fdre (and eventual gallium driver) to be
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able to work on existing kernel driver from QCOM, to allow to
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capture cmdstream dumps from the binary blob drivers without having
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to reboot. So libdrm_freedreno attempts to hide most of the crazy.
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The intention is that when there is a proper kernel driver, it will
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be mostly just changes in libdrm_freedreno to adapt the gallium
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driver and xf86-video-freedreno (ignoring the fbdev->KMS changes).
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So don't look at freedreno as an example of how to write a libdrm
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module or a DRM driver.. it is just an attempt to paper over a non-
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standard kernel driver architecture.
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