• Eric Anholt's avatar
    drm/vc4: Use runtime autosuspend to avoid thrashing V3D power state. · 3a622346
    Eric Anholt authored
    The pm_runtime_put() we were using immediately released power on the
    device, which meant that we were generally turning the device off and
    on once per frame.  In many profiles I've looked at, that added up to
    about 1% of CPU time, but this could get worse in the case of frequent
    rendering and readback (as may happen in X rendering).  By keeping the
    device on until we've been idle for a couple of frames, we drop the
    overhead of runtime PM down to sub-.1%.
    Signed-off-by: default avatarEric Anholt <eric@anholt.net>
    3a622346
vc4_drv.c 8.92 KB