From: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Date: Thu, 25 May 2017 18:39:49 -0400
Subject: drm/amd/display: stop adjusting scl taps when scl ratio is one on dcn
Git-commit: 259873e1ff3198d80f2dd50e3ab4249ad289e4c2
Patch-mainline: v4.15-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/display/dc/dcn10/dcn10_transform.c |   18 +++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_transform.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_transform.c
@@ -851,14 +851,16 @@ static bool transform_get_optimal_number
 	else
 		scl_data->taps.h_taps_c = in_taps->h_taps_c;
 
-	if (IDENTITY_RATIO(scl_data->ratios.horz))
-		scl_data->taps.h_taps = 1;
-	if (IDENTITY_RATIO(scl_data->ratios.vert))
-		scl_data->taps.v_taps = 1;
-	if (IDENTITY_RATIO(scl_data->ratios.horz_c))
-		scl_data->taps.h_taps_c = 1;
-	if (IDENTITY_RATIO(scl_data->ratios.vert_c))
-		scl_data->taps.v_taps_c = 1;
+	if (!xfm->ctx->dc->debug.always_scale) {
+		if (IDENTITY_RATIO(scl_data->ratios.horz))
+			scl_data->taps.h_taps = 1;
+		if (IDENTITY_RATIO(scl_data->ratios.vert))
+			scl_data->taps.v_taps = 1;
+		if (IDENTITY_RATIO(scl_data->ratios.horz_c))
+			scl_data->taps.h_taps_c = 1;
+		if (IDENTITY_RATIO(scl_data->ratios.vert_c))
+			scl_data->taps.v_taps_c = 1;
+	}
 
 	return true;
 }