drm/amd/display: Wait for flip to complete

[why]
In pipe split issue occurs when we program immediate flip while vsync flip is pending

[how]
Don't program immediate flip until flip is no longer pending

Signed-off-by: Alvin Lee <alvin.lee2@amd.com>
Reviewed-by: Jaehyun Chung <Jaehyun.Chung@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
index 5ecf965..9daab57 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
@@ -1308,6 +1308,17 @@ void dcn20_pipe_control_lock(
        if (pipe->plane_state != NULL)
                flip_immediate = pipe->plane_state->flip_immediate;
 
+       if (flip_immediate && lock) {
+               while (pipe->plane_res.hubp->funcs->hubp_is_flip_pending(pipe->plane_res.hubp)) {
+                       udelay(1);
+               }
+
+               if (pipe->bottom_pipe != NULL)
+                       while (pipe->bottom_pipe->plane_res.hubp->funcs->hubp_is_flip_pending(pipe->bottom_pipe->plane_res.hubp))       {
+                               udelay(1);
+                       }
+       }
+
        /* In flip immediate and pipe splitting case, we need to use GSL
         * for synchronization. Only do setup on locking and on flip type change.
         */