[PATCH 3/3] drm/amd/display: Destroy cached state in complete() callback

[Mario Limonciello]

From: Mario Limonciello <mario.limonciello at amd.com>

[Why]
When the suspend sequence has been aborted after prepare() but
before suspend() the resume() callback never gets called. The PM core
will call complete() when this happens. As the state has been cached
in prepare() it needs to be destroyed in complete() if it's still around.

[How]
Create a helper for destroying cached state and call it both in resume()
and complete() callbacks. If resume has been called the state will be
destroyed and it's a no-op for complete().  If resume hasn't been called
(such as an aborted suspend) then destroy the state in complete().

Fixes: 50e0bae34fa6b ("drm/amd/display: Add and use new dm_prepare_suspend() callback")
Signed-off-by: Mario Limonciello <mario.limonciello at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 100 +++++++++++-------
 1 file changed, 60 insertions(+), 40 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 1f5894d8f2fb1..94e5f07a51462 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -3073,6 +3073,64 @@ static int dm_cache_state(struct amdgpu_device *adev)
 	return adev->dm.cached_state ? 0 : r;
 }
 
+static void dm_destroy_cached_state(struct amdgpu_device *adev)
+{
+	struct amdgpu_display_manager *dm = &adev->dm;
+	struct drm_device *ddev = adev_to_drm(adev);
+	struct dm_plane_state *dm_new_plane_state;
+	struct drm_plane_state *new_plane_state;
+	struct dm_crtc_state *dm_new_crtc_state;
+	struct drm_crtc_state *new_crtc_state;
+	struct drm_plane *plane;
+	struct drm_crtc *crtc;
+	int i;
+
+	if (!dm->cached_state)
+		return;
+
+	/* Force mode set in atomic commit */
+	for_each_new_crtc_in_state(dm->cached_state, crtc, new_crtc_state, i) {
+		new_crtc_state->active_changed = true;
+		dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
+		reset_freesync_config_for_crtc(dm_new_crtc_state);
+	}
+
+	/*
+	 * atomic_check is expected to create the dc states. We need to release
+	 * them here, since they were duplicated as part of the suspend
+	 * procedure.
+	 */
+	for_each_new_crtc_in_state(dm->cached_state, crtc, new_crtc_state, i) {
+		dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
+		if (dm_new_crtc_state->stream) {
+			WARN_ON(kref_read(&dm_new_crtc_state->stream->refcount) > 1);
+			dc_stream_release(dm_new_crtc_state->stream);
+			dm_new_crtc_state->stream = NULL;
+		}
+		dm_new_crtc_state->base.color_mgmt_changed = true;
+	}
+
+	for_each_new_plane_in_state(dm->cached_state, plane, new_plane_state, i) {
+		dm_new_plane_state = to_dm_plane_state(new_plane_state);
+		if (dm_new_plane_state->dc_state) {
+			WARN_ON(kref_read(&dm_new_plane_state->dc_state->refcount) > 1);
+			dc_plane_state_release(dm_new_plane_state->dc_state);
+			dm_new_plane_state->dc_state = NULL;
+		}
+	}
+
+	drm_atomic_helper_resume(ddev, dm->cached_state);
+
+	dm->cached_state = NULL;
+}
+
+static void dm_complete(struct amdgpu_ip_block *ip_block)
+{
+	struct amdgpu_device *adev = ip_block->adev;
+
+	dm_destroy_cached_state(adev);
+}
+
 static int dm_prepare_suspend(struct amdgpu_ip_block *ip_block)
 {
 	struct amdgpu_device *adev = ip_block->adev;
@@ -3306,12 +3364,6 @@ static int dm_resume(struct amdgpu_ip_block *ip_block)
 	struct amdgpu_dm_connector *aconnector;
 	struct drm_connector *connector;
 	struct drm_connector_list_iter iter;
-	struct drm_crtc *crtc;
-	struct drm_crtc_state *new_crtc_state;
-	struct dm_crtc_state *dm_new_crtc_state;
-	struct drm_plane *plane;
-	struct drm_plane_state *new_plane_state;
-	struct dm_plane_state *dm_new_plane_state;
 	struct dm_atomic_state *dm_state = to_dm_atomic_state(dm->atomic_obj.state);
 	enum dc_connection_type new_connection_type = dc_connection_none;
 	struct dc_state *dc_state;
@@ -3468,40 +3520,7 @@ static int dm_resume(struct amdgpu_ip_block *ip_block)
 	}
 	drm_connector_list_iter_end(&iter);
 
-	/* Force mode set in atomic commit */
-	for_each_new_crtc_in_state(dm->cached_state, crtc, new_crtc_state, i) {
-		new_crtc_state->active_changed = true;
-		dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
-		reset_freesync_config_for_crtc(dm_new_crtc_state);
-	}
-
-	/*
-	 * atomic_check is expected to create the dc states. We need to release
-	 * them here, since they were duplicated as part of the suspend
-	 * procedure.
-	 */
-	for_each_new_crtc_in_state(dm->cached_state, crtc, new_crtc_state, i) {
-		dm_new_crtc_state = to_dm_crtc_state(new_crtc_state);
-		if (dm_new_crtc_state->stream) {
-			WARN_ON(kref_read(&dm_new_crtc_state->stream->refcount) > 1);
-			dc_stream_release(dm_new_crtc_state->stream);
-			dm_new_crtc_state->stream = NULL;
-		}
-		dm_new_crtc_state->base.color_mgmt_changed = true;
-	}
-
-	for_each_new_plane_in_state(dm->cached_state, plane, new_plane_state, i) {
-		dm_new_plane_state = to_dm_plane_state(new_plane_state);
-		if (dm_new_plane_state->dc_state) {
-			WARN_ON(kref_read(&dm_new_plane_state->dc_state->refcount) > 1);
-			dc_plane_state_release(dm_new_plane_state->dc_state);
-			dm_new_plane_state->dc_state = NULL;
-		}
-	}
-
-	drm_atomic_helper_resume(ddev, dm->cached_state);
-
-	dm->cached_state = NULL;
+	dm_destroy_cached_state(adev);
 
 	/* Do mst topology probing after resuming cached state*/
 	drm_connector_list_iter_begin(ddev, &iter);
@@ -3550,6 +3569,7 @@ static const struct amd_ip_funcs amdgpu_dm_funcs = {
 	.prepare_suspend = dm_prepare_suspend,
 	.suspend = dm_suspend,
 	.resume = dm_resume,
+	.complete = dm_complete,
 	.is_idle = dm_is_idle,
 	.wait_for_idle = dm_wait_for_idle,
 	.check_soft_reset = dm_check_soft_reset,
-- 
2.43.0