drm/amd/display: Explicitly specify update type per plane info change

[Why]
The bit for flip addr is being set causing the determination for
FAST vs MEDIUM to always return MEDIUM when plane info is provided
as a surface update. This causes extreme stuttering for the typical
atomic update path on Linux.

[How]
Don't use update_flags->raw for determining FAST vs MEDIUM. It's too
fragile to changes like this.

Explicitly specify the update type per update flag instead. It's not
as clever as checking the bits itself but at least it's correct.
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Acked-by: Eryk Brol <Eryk.Brol@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -1333,74 +1333,94 @@ static bool is_surface_in_context(
 static enum surface_update_type get_plane_info_update_type(const struct dc_surface_update *u)
 {
 	union surface_update_flags *update_flags = &u->surface->update_flags;
+	enum surface_update_type update_type = UPDATE_TYPE_FAST;
 
 	if (!u->plane_info)
 		return UPDATE_TYPE_FAST;
 
-	if (u->plane_info->color_space != u->surface->color_space)
+	if (u->plane_info->color_space != u->surface->color_space) {
 		update_flags->bits.color_space_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+	}
 
-	if (u->plane_info->horizontal_mirror != u->surface->horizontal_mirror)
+	if (u->plane_info->horizontal_mirror != u->surface->horizontal_mirror) {
 		update_flags->bits.horizontal_mirror_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+	}
 
-	if (u->plane_info->rotation != u->surface->rotation)
+	if (u->plane_info->rotation != u->surface->rotation) {
 		update_flags->bits.rotation_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_FULL);
+	}
 
-	if (u->plane_info->format != u->surface->format)
+	if (u->plane_info->format != u->surface->format) {
 		update_flags->bits.pixel_format_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_FULL);
+	}
 
-	if (u->plane_info->stereo_format != u->surface->stereo_format)
+	if (u->plane_info->stereo_format != u->surface->stereo_format) {
 		update_flags->bits.stereo_format_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_FULL);
+	}
 
-	if (u->plane_info->per_pixel_alpha != u->surface->per_pixel_alpha)
+	if (u->plane_info->per_pixel_alpha != u->surface->per_pixel_alpha) {
 		update_flags->bits.per_pixel_alpha_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+	}
 
-	if (u->plane_info->global_alpha_value != u->surface->global_alpha_value)
+	if (u->plane_info->global_alpha_value != u->surface->global_alpha_value) {
 		update_flags->bits.global_alpha_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+	}
 
-	if (u->plane_info->sdr_white_level != u->surface->sdr_white_level)
+	if (u->plane_info->sdr_white_level != u->surface->sdr_white_level) {
 		update_flags->bits.sdr_white_level = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+	}
 
 	if (u->plane_info->dcc.enable != u->surface->dcc.enable
 			|| u->plane_info->dcc.grph.independent_64b_blks != u->surface->dcc.grph.independent_64b_blks
-			|| u->plane_info->dcc.grph.meta_pitch != u->surface->dcc.grph.meta_pitch)
+			|| u->plane_info->dcc.grph.meta_pitch != u->surface->dcc.grph.meta_pitch) {
 		update_flags->bits.dcc_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+	}
 
 	if (resource_pixel_format_to_bpp(u->plane_info->format) !=
-			resource_pixel_format_to_bpp(u->surface->format))
+			resource_pixel_format_to_bpp(u->surface->format)) {
 		/* different bytes per element will require full bandwidth
 		 * and DML calculation
 		 */
 		update_flags->bits.bpp_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_FULL);
+	}
 
 	if (u->plane_info->plane_size.grph.surface_pitch != u->surface->plane_size.grph.surface_pitch
 			|| u->plane_info->plane_size.video.luma_pitch != u->surface->plane_size.video.luma_pitch
-			|| u->plane_info->plane_size.video.chroma_pitch != u->surface->plane_size.video.chroma_pitch)
+			|| u->plane_info->plane_size.video.chroma_pitch != u->surface->plane_size.video.chroma_pitch) {
 		update_flags->bits.plane_size_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+	}
 
 
 	if (memcmp(&u->plane_info->tiling_info, &u->surface->tiling_info,
 			sizeof(union dc_tiling_info)) != 0) {
 		update_flags->bits.swizzle_change = 1;
+		elevate_update_type(&update_type, UPDATE_TYPE_MED);
+
 		/* todo: below are HW dependent, we should add a hook to
 		 * DCE/N resource and validated there.
 		 */
-		if (u->plane_info->tiling_info.gfx9.swizzle != DC_SW_LINEAR)
+		if (u->plane_info->tiling_info.gfx9.swizzle != DC_SW_LINEAR) {
 			/* swizzled mode requires RQ to be setup properly,
 			 * thus need to run DML to calculate RQ settings
 			 */
 			update_flags->bits.bandwidth_change = 1;
+			elevate_update_type(&update_type, UPDATE_TYPE_FULL);
+		}
 	}
 
-	if (update_flags->bits.rotation_change
-			|| update_flags->bits.stereo_format_change
-			|| update_flags->bits.pixel_format_change
-			|| update_flags->bits.bpp_change
-			|| update_flags->bits.bandwidth_change
-			|| update_flags->bits.output_tf_change)
-		return UPDATE_TYPE_FULL;
-
-	return update_flags->raw ? UPDATE_TYPE_MED : UPDATE_TYPE_FAST;
+	/* This should be UPDATE_TYPE_FAST if nothing has changed. */
+	return update_type;
 }
 
 static enum surface_update_type get_scaling_info_update_type(
@@ -1464,9 +1484,6 @@ static enum surface_update_type det_surface_update(const struct dc *dc,
 
 	update_flags->raw = 0; // Reset all flags
 
-	if (u->flip_addr)
-		update_flags->bits.addr_update = 1;
-
 	if (!is_surface_in_context(context, u->surface)) {
 		update_flags->bits.new_plane = 1;
 		return UPDATE_TYPE_FULL;
@@ -1483,6 +1500,9 @@ static enum surface_update_type det_surface_update(const struct dc *dc,
 	type = get_scaling_info_update_type(u);
 	elevate_update_type(&overall_type, type);
 
+	if (u->flip_addr)
+		update_flags->bits.addr_update = 1;
+
 	if (u->in_transfer_func)
 		update_flags->bits.in_transfer_func_change = 1;