[Intel-gfx] [RFC 13/33] drm: Reset plane color state on pipeline switch request

[Uma Shankar <uma.shankar@intel.com>]

From: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>

When a pipeline switch is requested by user, driver resets
blobs for all the hardware blocks to get to clean state. These
are then populated with the new blob id's as programmed by user.
For the already enabled hardware blocks, if the user does not
add entry in the new switch request, the blob id's will remain
NULL eventually resulting in disabling of that hardware block.

Co-developed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
---
 drivers/gpu/drm/drm_atomic_uapi.c | 52 ++++++++++++++++++++++++++++---
 1 file changed, 48 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index 259cd4f5f520..9e0fb36d1f47 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -362,6 +362,38 @@ static s32 __user *get_out_fence_for_connector(struct drm_atomic_state *state,
 	return fence_ptr;
 }
 
+static
+bool color_pipeline_change_requested(struct drm_device *dev,
+				     struct drm_property_blob *plane_cp_set_blob,
+				     uint64_t blob_id)
+{
+	bool is_change_requested = false;
+	struct drm_property_blob *new_blob = NULL;
+	struct drm_color_pipeline *old_cp, *new_cp;
+
+	/*
+	 * User is setting the pipeline for the first time
+	 */
+	if (!plane_cp_set_blob)
+		goto out;
+
+	old_cp = plane_cp_set_blob->data;
+
+	if (blob_id != 0) {
+		new_blob = drm_property_lookup_blob(dev, blob_id);
+		if (!new_blob)
+			goto out;
+
+		new_cp = new_blob->data;
+
+		if (old_cp->num != new_cp->num)
+			is_change_requested = true;
+	}
+	drm_property_blob_put(new_blob);
+out:
+	return is_change_requested;
+}
+
 static int
 drm_atomic_replace_property_blob_from_id(struct drm_device *dev,
 					 struct drm_property_blob **blob,
@@ -727,6 +759,12 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
 	} else if (property == plane->scaling_filter_property) {
 		state->scaling_filter = val;
 	} else if (property == plane->set_color_pipeline_prop) {
+		bool cp_change_requested;
+
+		cp_change_requested = color_pipeline_change_requested(dev,
+						state->set_color_pipeline_data,
+						val);
+
 		ret = drm_atomic_replace_property_blob_from_id(dev,
 					&state->set_color_pipeline_data,
 					val,
@@ -736,12 +774,18 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
 		if (replaced) {
 			/* Consider actual color parameter change only when
 			 * individual color blobs are replaced. Hence, reset
-			 * the replaced boolean.
+			 * the replaced boolean but first reset all color
+			 * blobs if color pipeline change is requested.
 			 */
+			if (val && cp_change_requested)
+				ret = drm_plane_reset_color_op_blobs(plane,
+								state, &replaced);
 			replaced = false;
-			ret = drm_plane_replace_color_op_blobs(plane, state,
-							       val,
-							       &replaced);
+			if (!ret) {
+				ret = drm_plane_replace_color_op_blobs(plane, state,
+								       val,
+								       &replaced);
+			}
 		}
 
 		state->color_mgmt_changed |= replaced;
-- 
2.38.1