[PATCH 17/21] drm/amd/display: Clip rect size changes should be full updates

[Aurabindo Pillai]

From: Joshua Aberback <joshua.aberback at amd.com>

[Why]
In cases where an MPO plane is being dragged around partially off-screen,
it is possible to get a flip where the only scaling parameters to change
are the clip rect size and position. Currently, clip rect size changes
are considered medium updates, which can result in the clip rect being used
for HW programming being larger than the clip rect that was used for the
last DML validation. This can lead to mismatches in different parts of the
pipe and can result in a p-state hang.

[How]
 - consider clip rect size changes scaling changes, therefore full updates
 - refactor get_scaling_info_update_type for clarity
 - remove clip_size_change update flag

Clip rect size changes were previously demoted from full updates as an
optimization when the MPO + ODM policy changed to always pre-allocate MPO
pipes, but it created the issue described above. Personally testing this
use case, the performance feels fine with full update spam, and we expect
this is a fairly infrequent use case. If the performance needs to be
optimized in the future, consider reworking the entire update type logic
to run a DML pass and determine the update type based on what DML says
will actually change.

Reviewed-by: Dillon Varone <dillon.varone at amd.com>
Signed-off-by: Joshua Aberback <joshua.aberback at amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc.c      | 45 ++++++++-----------
 drivers/gpu/drm/amd/display/dc/dc.h           |  1 -
 .../amd/display/dc/hwss/dcn20/dcn20_hwseq.c   |  2 -
 3 files changed, 19 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index fbc2e1dfb610..5c9a88e834e6 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -2515,41 +2515,35 @@ static enum surface_update_type get_scaling_info_update_type(
 	if (!u->scaling_info)
 		return UPDATE_TYPE_FAST;
 
-	if (u->scaling_info->dst_rect.width != u->surface->dst_rect.width
+	if (u->scaling_info->src_rect.width != u->surface->src_rect.width
+			|| u->scaling_info->src_rect.height != u->surface->src_rect.height
+			|| u->scaling_info->dst_rect.width != u->surface->dst_rect.width
 			|| u->scaling_info->dst_rect.height != u->surface->dst_rect.height
+			|| u->scaling_info->clip_rect.width != u->surface->clip_rect.width
+			|| u->scaling_info->clip_rect.height != u->surface->clip_rect.height
 			|| u->scaling_info->scaling_quality.integer_scaling !=
-				u->surface->scaling_quality.integer_scaling
-			) {
+					u->surface->scaling_quality.integer_scaling) {
 		update_flags->bits.scaling_change = 1;
 
+		if (u->scaling_info->src_rect.width > u->surface->src_rect.width
+				|| u->scaling_info->src_rect.height > u->surface->src_rect.height)
+			/* Making src rect bigger requires a bandwidth change */
+			update_flags->bits.clock_change = 1;
+
 		if ((u->scaling_info->dst_rect.width < u->surface->dst_rect.width
 			|| u->scaling_info->dst_rect.height < u->surface->dst_rect.height)
 				&& (u->scaling_info->dst_rect.width < u->surface->src_rect.width
 					|| u->scaling_info->dst_rect.height < u->surface->src_rect.height))
 			/* Making dst rect smaller requires a bandwidth change */
 			update_flags->bits.bandwidth_change = 1;
-	}
-
-	if (u->scaling_info->src_rect.width != u->surface->src_rect.width
-		|| u->scaling_info->src_rect.height != u->surface->src_rect.height) {
 
-		update_flags->bits.scaling_change = 1;
-		if (u->scaling_info->src_rect.width > u->surface->src_rect.width
-				|| u->scaling_info->src_rect.height > u->surface->src_rect.height)
-			/* Making src rect bigger requires a bandwidth change */
-			update_flags->bits.clock_change = 1;
+		if (u->scaling_info->src_rect.width > dc->caps.max_optimizable_video_width &&
+			(u->scaling_info->clip_rect.width > u->surface->clip_rect.width ||
+			 u->scaling_info->clip_rect.height > u->surface->clip_rect.height))
+			 /* Changing clip size of a large surface may result in MPC slice count change */
+			update_flags->bits.bandwidth_change = 1;
 	}
 
-	if (u->scaling_info->src_rect.width > dc->caps.max_optimizable_video_width &&
-		(u->scaling_info->clip_rect.width > u->surface->clip_rect.width ||
-		 u->scaling_info->clip_rect.height > u->surface->clip_rect.height))
-		 /* Changing clip size of a large surface may result in MPC slice count change */
-		update_flags->bits.bandwidth_change = 1;
-
-	if (u->scaling_info->clip_rect.width != u->surface->clip_rect.width ||
-			u->scaling_info->clip_rect.height != u->surface->clip_rect.height)
-		update_flags->bits.clip_size_change = 1;
-
 	if (u->scaling_info->src_rect.x != u->surface->src_rect.x
 			|| u->scaling_info->src_rect.y != u->surface->src_rect.y
 			|| u->scaling_info->clip_rect.x != u->surface->clip_rect.x
@@ -2558,13 +2552,13 @@ static enum surface_update_type get_scaling_info_update_type(
 			|| u->scaling_info->dst_rect.y != u->surface->dst_rect.y)
 		update_flags->bits.position_change = 1;
 
+	/* process every update flag before returning */
 	if (update_flags->bits.clock_change
 			|| update_flags->bits.bandwidth_change
 			|| update_flags->bits.scaling_change)
 		return UPDATE_TYPE_FULL;
 
-	if (update_flags->bits.position_change ||
-			update_flags->bits.clip_size_change)
+	if (update_flags->bits.position_change)
 		return UPDATE_TYPE_MED;
 
 	return UPDATE_TYPE_FAST;
@@ -3263,8 +3257,7 @@ static bool update_planes_and_stream_state(struct dc *dc,
 
 		if (update_type != UPDATE_TYPE_MED)
 			continue;
-		if (surface->update_flags.bits.clip_size_change ||
-				surface->update_flags.bits.position_change) {
+		if (surface->update_flags.bits.position_change) {
 			for (j = 0; j < dc->res_pool->pipe_count; j++) {
 				struct pipe_ctx *pipe_ctx = &context->res_ctx.pipe_ctx[j];
 
diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index d3b6a389fece..6d60f7597f88 100644
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -1254,7 +1254,6 @@ union surface_update_flags {
 		uint32_t rotation_change:1;
 		uint32_t swizzle_change:1;
 		uint32_t scaling_change:1;
-		uint32_t clip_size_change: 1;
 		uint32_t position_change:1;
 		uint32_t in_transfer_func_change:1;
 		uint32_t input_csc_change:1;
diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
index b383ed8cb4d4..e89499536c46 100644
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
@@ -1732,7 +1732,6 @@ static void dcn20_update_dchubp_dpp(
 	if (pipe_ctx->update_flags.bits.scaler ||
 			plane_state->update_flags.bits.scaling_change ||
 			plane_state->update_flags.bits.position_change ||
-			plane_state->update_flags.bits.clip_size_change ||
 			plane_state->update_flags.bits.per_pixel_alpha_change ||
 			pipe_ctx->stream->update_flags.bits.scaling) {
 		pipe_ctx->plane_res.scl_data.lb_params.alpha_en = pipe_ctx->plane_state->per_pixel_alpha;
@@ -1745,7 +1744,6 @@ static void dcn20_update_dchubp_dpp(
 	if (pipe_ctx->update_flags.bits.viewport ||
 			(context == dc->current_state && plane_state->update_flags.bits.position_change) ||
 			(context == dc->current_state && plane_state->update_flags.bits.scaling_change) ||
-			(context == dc->current_state && plane_state->update_flags.bits.clip_size_change) ||
 			(context == dc->current_state && pipe_ctx->stream->update_flags.bits.scaling)) {
 
 		hubp->funcs->mem_program_viewport(
-- 
2.46.0