[PATCH 06/16] drm/amd/display: temporary clamp the vratio used to 1.0

[Aurabindo Pillai]

From: Lewis Huang <Lewis.Huang at amd.com>

[Why]
in Is_Support function, driver report different caps between
same timing but different scaling cause OS inconsistent.

[How]
min_row_time is a local that’s only used for verifying immediate
flip support. Clamp the vratio used for its calculation to 1.0.

Signed-off-by: Lewis Huang <Lewis.Huang at amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng at amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai at amd.com>
---
 .../dc/dml/dcn21/display_mode_vba_21.c        | 26 ++++++++++---------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_mode_vba_21.c b/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_mode_vba_21.c
index 5bc80b6084da..a576eed94d9b 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_mode_vba_21.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn21/display_mode_vba_21.c
@@ -3190,6 +3190,7 @@ static void CalculateFlipSchedule(
 	double TimeForFetchingRowInVBlankImmediateFlip;
 	double ImmediateFlipBW;
 	double HostVMInefficiencyFactor;
+	double VRatioClamped;
 
 	if (GPUVMEnable == true && HostVMEnable == true) {
 		HostVMInefficiencyFactor =
@@ -3222,31 +3223,32 @@ static void CalculateFlipSchedule(
 
 	*DestinationLinesToRequestRowInImmediateFlip = dml_ceil(4.0 * (TimeForFetchingRowInVBlankImmediateFlip / LineTime), 1) / 4.0;
 	*final_flip_bw = dml_max(PDEAndMetaPTEBytesPerFrame * HostVMInefficiencyFactor / (*DestinationLinesToRequestVMInImmediateFlip * LineTime), (MetaRowBytes + DPTEBytesPerRow) * HostVMInefficiencyFactor / (*DestinationLinesToRequestRowInImmediateFlip * LineTime));
+	VRatioClamped = (VRatio < 1.0) ? 1.0 : VRatio;
 	if (SourcePixelFormat == dm_420_8 || SourcePixelFormat == dm_420_10) {
 		if (GPUVMEnable == true && DCCEnable != true) {
 			min_row_time = dml_min(
-					dpte_row_height * LineTime / VRatio,
-					dpte_row_height_chroma * LineTime / (VRatio / 2));
+					dpte_row_height * LineTime / VRatioClamped,
+					dpte_row_height_chroma * LineTime / (VRatioClamped / 2));
 		} else if (GPUVMEnable != true && DCCEnable == true) {
 			min_row_time = dml_min(
-					meta_row_height * LineTime / VRatio,
-					meta_row_height_chroma * LineTime / (VRatio / 2));
+					meta_row_height * LineTime / VRatioClamped,
+					meta_row_height_chroma * LineTime / (VRatioClamped / 2));
 		} else {
 			min_row_time = dml_min4(
-					dpte_row_height * LineTime / VRatio,
-					meta_row_height * LineTime / VRatio,
-					dpte_row_height_chroma * LineTime / (VRatio / 2),
-					meta_row_height_chroma * LineTime / (VRatio / 2));
+					dpte_row_height * LineTime / VRatioClamped,
+					meta_row_height * LineTime / VRatioClamped,
+					dpte_row_height_chroma * LineTime / (VRatioClamped / 2),
+					meta_row_height_chroma * LineTime / (VRatioClamped / 2));
 		}
 	} else {
 		if (GPUVMEnable == true && DCCEnable != true) {
-			min_row_time = dpte_row_height * LineTime / VRatio;
+			min_row_time = dpte_row_height * LineTime / VRatioClamped;
 		} else if (GPUVMEnable != true && DCCEnable == true) {
-			min_row_time = meta_row_height * LineTime / VRatio;
+			min_row_time = meta_row_height * LineTime / VRatioClamped;
 		} else {
 			min_row_time = dml_min(
-					dpte_row_height * LineTime / VRatio,
-					meta_row_height * LineTime / VRatio);
+					dpte_row_height * LineTime / VRatioClamped,
+					meta_row_height * LineTime / VRatioClamped);
 		}
 	}
 
-- 
2.25.1