drm/msm/gpu: Bypass PM QoS constraint for idle clamp

[ Upstream commit fadcc3ab ]

Change idle freq clamping back to the direct method, bypassing PM QoS
requests.  The problem with using PM QoS requests is they call
(indirectly) the governors ->get_target_freq() which goes thru a
get_dev_status() cycle.  The problem comes when the GPU becomes active
again and we remove the idle-clamp request, we go through another
get_dev_status() cycle for the period that the GPU has been idle, which
triggers the governor to lower the target freq excessively.

This partially reverts commit 7c0ffcd4 ("drm/msm/gpu: Respect PM QoS
constraints"), but preserves the use of boost QoS request, so that it
will continue to play nicely with other QoS requests such as a cooling
device.  This also mostly undoes commit 78f815c1 ("drm/msm: return the
average load over the polling period")

Signed-off-by: Rob Clark <robdclark@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/517785/
Link: https://lore.kernel.org/r/20230110231447.1939101-3-robdclark@gmail.com


Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Stable-dep-of: 8f32ddd8 ("drm/msm/gpu: Check the status of registration to PM QoS")
Signed-off-by: Sasha Levin <sashal@kernel.org>