From: Tony Cheng <tony.cheng@amd.com>
Date: Fri, 23 Dec 2016 07:20:53 -0500
Subject: drm/amd/display: debug option to disable color module fucntionality
Git-commit: e12078c56c24894b07cd3aae43788b90d6ea390e
Patch-mainline: v4.15-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

Signed-off-by: Tony Cheng <tony.cheng@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@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/core/dc.c |   13 +++++++------
 drivers/gpu/drm/amd/display/dc/dc.h      |    1 +
 2 files changed, 8 insertions(+), 6 deletions(-)

--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -1452,8 +1452,11 @@ void dc_update_surfaces_for_target(struc
 				}
 			}
 
-			if (updates[i].gamma && updates[i].gamma !=
-				surface->public.gamma_correction) {
+			if (dc->debug.disable_color_module)
+				continue;  /* skip below color updates */
+
+			if (updates[i].gamma &&
+				updates[i].gamma != surface->public.gamma_correction) {
 				if (surface->public.gamma_correction != NULL)
 					dc_gamma_release(surface->public.
 							gamma_correction);
@@ -1464,8 +1467,7 @@ void dc_update_surfaces_for_target(struc
 			}
 
 			if (updates[i].in_transfer_func &&
-					updates[i].in_transfer_func !=
-					surface->public.in_transfer_func) {
+				updates[i].in_transfer_func != surface->public.in_transfer_func) {
 				if (surface->public.in_transfer_func != NULL)
 					dc_transfer_func_release(
 							surface->public.
@@ -1478,8 +1480,7 @@ void dc_update_surfaces_for_target(struc
 			}
 
 			if (updates[i].out_transfer_func &&
-					updates[i].out_transfer_func !=
-					stream->public.out_transfer_func) {
+				updates[i].out_transfer_func != stream->public.out_transfer_func) {
 				if (stream->public.out_transfer_func != NULL)
 					dc_transfer_func_release(
 							stream->public.
--- a/drivers/gpu/drm/amd/display/dc/dc.h
+++ b/drivers/gpu/drm/amd/display/dc/dc.h
@@ -148,6 +148,7 @@ struct dc_debug {
 	bool disable_clock_gate;
 	bool disable_dmcu;
 	bool disable_hdmi_deep_color;
+	bool disable_color_module;
 };
 
 struct dc {