[PATCH 102/103] drm/amd/display: Report stream as different on scaling change

[Harry Wentland]

From: "Leo (Sunpeng) Li" <sunpeng.li at amd.com>

When scaling is enabled, our preference is to scale up to the prefered
(native) mode. This means that hardware timings will be the same across
a modeset.

Therefore, also report mode as changed if source or destination
rectangle is different.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li at amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland at amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 10 +++++-----
 drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 22 ++++++++++++++++++++++
 drivers/gpu/drm/amd/display/dc/dc.h               |  2 ++
 3 files changed, 29 insertions(+), 5 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 351e398cb445..6d97486e074b 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -4593,13 +4593,13 @@ static int dm_update_crtcs_state(
 			}
 		}
 
-		if (dc_is_stream_unchanged(new_stream,
-				old_acrtc_state->stream)) {
+		if (dc_is_stream_unchanged(new_stream, old_acrtc_state->stream) &&
+				dc_is_stream_scaling_unchanged(new_stream, old_acrtc_state->stream)) {
 
-				crtc_state->mode_changed = false;
+			crtc_state->mode_changed = false;
 
-				DRM_DEBUG_DRIVER("Mode change not required, setting mode_changed to %d",
-					      crtc_state->mode_changed);
+			DRM_DEBUG_DRIVER("Mode change not required, setting mode_changed to %d",
+				         crtc_state->mode_changed);
 		}
 
 
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
index 454a521a268d..2a5c91772473 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -1335,6 +1335,28 @@ bool dc_is_stream_unchanged(
 	return true;
 }
 
+bool dc_is_stream_scaling_unchanged(
+	struct dc_stream_state *old_stream, struct dc_stream_state *stream)
+{
+	if (old_stream == stream)
+		return true;
+
+	if (old_stream == NULL || stream == NULL)
+		return false;
+
+	if (memcmp(&old_stream->src,
+			&stream->src,
+			sizeof(struct rect)) != 0)
+		return false;
+
+	if (memcmp(&old_stream->dst,
+			&stream->dst,
+			sizeof(struct rect)) != 0)
+		return false;
+
+	return true;
+}
+
 /* Maximum TMDS single link pixel clock 165MHz */
 #define TMDS_MAX_PIXEL_CLOCK_IN_KHZ 165000
 
diff --git a/drivers/gpu/drm/amd/display/dc/dc.h b/drivers/gpu/drm/amd/display/dc/dc.h
index ace17d13683a..f60191d9c7e5 100644
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -627,6 +627,8 @@ struct dc_stream_update {
 
 bool dc_is_stream_unchanged(
 	struct dc_stream_state *old_stream, struct dc_stream_state *stream);
+bool dc_is_stream_scaling_unchanged(
+	struct dc_stream_state *old_stream, struct dc_stream_state *stream);
 
 /*
  * Set up surface attributes and associate to a stream
-- 
2.14.1