[PATCH v2 12/12] drm/amd/display: Move dc_state copy in commit_tail after dc_commit_state

[Rodrigo Siqueira]

From: Aurabindo Pillai <aurabindo.pillai at amd.com>

The SubVP feature introduces a new mechanism named phantom streams,
which can be summed up as a fake stream used to calculate the required
parameters for handing the cache request and cache reading for a small
portion of the framebuffer used in the sub-viewport. With the new commit
sequence, we do not want the state to be copied before the call to
dc_commit_state() since this leaks the phantom streams into new state.
To address this issue, this commit move the dc state copy right after
the dc_commit_state() call.

Signed-off-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c   | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

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 63f076a46260..17a9108f8186 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7999,15 +7999,8 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
 	drm_atomic_helper_update_legacy_modeset_state(dev, state);
 
 	dm_state = dm_atomic_get_new_state(state);
-	if (dm_state && dm_state->context) {
+	if (dm_state && dm_state->context)
 		dc_state = dm_state->context;
-	} else {
-		/* No state changes, retain current state. */
-		dc_state_temp = dc_create_state(dm->dc);
-		ASSERT(dc_state_temp);
-		dc_state = dc_state_temp;
-		dc_resource_state_copy_construct_current(dm->dc, dc_state);
-	}
 
 	for_each_oldnew_crtc_in_state (state, crtc, old_crtc_state,
 				       new_crtc_state, i) {
@@ -8127,6 +8120,14 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
 		mutex_unlock(&dm->dc_lock);
 	}
 
+	if (dc_state == NULL) {
+		/* No state changes, retain current state. */
+		dc_state_temp = dc_create_state(dm->dc);
+		ASSERT(dc_state_temp);
+		dc_state = dc_state_temp;
+		dc_resource_state_copy_construct_current(dm->dc, dc_state);
+	}
+
 	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
 		struct amdgpu_crtc *acrtc = to_amdgpu_crtc(crtc);
 
-- 
2.38.0