[PATCH 31/36] drm/amd/display: Update DRAM watermark before checking to update TTU

[Rodrigo Siqueira]

From: Jaehyun Chung <jaehyun.chung at amd.com>

[Why]
In most cases, DRAM watermark is large enough that the result of the
condition to increase TTU doesn't change after DRAM watermark is
increased. However, there is are cases where the condition fails and
becomes true after DRAM watermark is increased. This results in minTTU <
DRAM watermarks which leads to PSR hang since p-state is requested but
not allowed.

[How]
Check whether to update TTU after DRAM watermark is updated.

Signed-off-by: Jaehyun Chung <jaehyun.chung at amd.com>
Reviewed-by: Jun Lei <Jun.Lei at amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira at amd.com>
---
 .../gpu/drm/amd/display/dc/dml/dcn20/display_mode_vba_20v2.c   | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn20/display_mode_vba_20v2.c b/drivers/gpu/drm/amd/display/dc/dml/dcn20/display_mode_vba_20v2.c
index 5bbbafacc720..922ab7169e52 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn20/display_mode_vba_20v2.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn20/display_mode_vba_20v2.c
@@ -2614,6 +2614,7 @@ static void dml20v2_DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndP
 
 	if (mode_lib->vba.DRAMClockChangeSupportsVActive &&
 			mode_lib->vba.MinActiveDRAMClockChangeMargin > 60) {
+		mode_lib->vba.DRAMClockChangeWatermark += 25;
 
 		for (k = 0; k < mode_lib->vba.NumberOfActivePlanes; ++k) {
 			if (mode_lib->vba.PrefetchMode[mode_lib->vba.VoltageLevel][mode_lib->vba.maxMpcComb] == 0) {
@@ -2622,7 +2623,7 @@ static void dml20v2_DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndP
 					mode_lib->vba.MinTTUVBlank[k] += 25;
 			}
 		}
-		mode_lib->vba.DRAMClockChangeWatermark += 25;
+
 		mode_lib->vba.DRAMClockChangeSupport[0][0] = dm_dram_clock_change_vactive;
 	} else if (mode_lib->vba.DummyPStateCheck &&
 			mode_lib->vba.MinActiveDRAMClockChangeMargin > 0) {
-- 
2.26.0