[PATCH 16/66] drm/amd/display: Fix hang when skipping modeset

[Qingqing Zhuo]

From: Aurabindo Pillai <aurabindo.pil...@amd.com>

[Why&How]

When skipping full modeset since the only state change was a front porch
change, the DC commit sequence requires extra checks to handle non
existant plane states being asked to be removed from context.

Reviewed-by: Alvin Lee <alvin.l...@amd.com>
Acked-by: Qingqing Zhuo <qingqing.z...@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pil...@amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 5 ++++-
 drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 3 +++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c 
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index da3045fdcb6d..8b4a470a7e60 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7971,6 +7971,8 @@ static void amdgpu_dm_commit_planes(struct 
drm_atomic_state *state,
                        continue;
 
                dc_plane = dm_new_plane_state->dc_state;
+               if (!dc_plane)
+                       continue;
 
                bundle->surface_updates[planes_count].surface = dc_plane;
                if (new_pcrtc_state->color_mgmt_changed) {
@@ -9619,8 +9621,9 @@ static int dm_update_plane_state(struct dc *dc,
                        return -EINVAL;
                }
 
+               if (dm_old_plane_state->dc_state)
+                       dc_plane_state_release(dm_old_plane_state->dc_state);
 
-               dc_plane_state_release(dm_old_plane_state->dc_state);
                dm_new_plane_state->dc_state = NULL;
 
                *lock_and_validation_needed = true;
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c 
b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
index 85d54bfb595c..117d80cb36fb 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -1707,6 +1707,9 @@ bool dc_remove_plane_from_context(
        struct dc_stream_status *stream_status = NULL;
        struct resource_pool *pool = dc->res_pool;
 
+       if (!plane_state)
+               return true;
+
        for (i = 0; i < context->stream_count; i++)
                if (context->streams[i] == stream) {
                        stream_status = &context->stream_status[i];
-- 
2.34.1