[PATCH] drm/msm/mdp5: Fix wait-for-commit for cmd panels

[Alexey Minnekhanov]

On 1/27/21 6:24 PM, Iskren Chernev wrote:
> Before the offending commit in msm_atomic_commit_tail wait_flush was
> called once per frame, after the commit was submitted. After it
> wait_flush is also called at the beginning to ensure previous
> potentially async commits are done.
> 
> For cmd panels the source of wait_flush is a ping-pong irq notifying
> a completion. The completion needs to be notified with complete_all so
> multiple waiting parties (new async committers) can proceed.
> 
> Signed-off-by: Iskren Chernev <iskren.chernev at gmail.com>
> Suggested-by: Rob Clark <robdclark at gmail.com>
> Fixes: 2d99ced787e3d ("drm/msm: async commit support")
> 

Tested on msm8974pro samsung-klte, finally got 60 fps instead of 13
in kmscube.

Tested-by: Alexey Minnekhanov <alexeymin at postmarketos.org>