[PATCH 5.10 010/152] Revert "drm/amd/display: Fixed Intermittent blue screen on OLED panel"

From: Greg Kroah-Hartman
Date: Mon Jan 18 2021 - 06:52:57 EST


From: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>

commit 4eec66c014e9a406d8d453de958f6791d05427e4 upstream.

commit a861736dae64 ("drm/amd/display: Fixed Intermittent blue screen on OLED panel")

causes power regression for many users. It seems that this change causes
the MCLK to get forced high; this creates a regression for many users
since their devices were not able to drop to a low state after this
change. For this reason, this reverts commit
a861736dae644a0d7abbca0c638ae6aad28feeb8.

Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1407
Cc: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: Harry Wentland <harry.wentland@xxxxxxx>
Cc: Naveed Ashfaq <Naveed.Ashfaq@xxxxxxx>
Cc: Hersen Wu <hersenxs.wu@xxxxxxx>
Cc: Roman Li <roman.li@xxxxxxx>
Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/amd/display/dc/dml/dcn20/display_mode_vba_20v2.c | 11 +++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

--- 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
@@ -2635,14 +2635,15 @@ static void dml20v2_DISPCLKDPPCLKDCFCLKD
}

if (mode_lib->vba.DRAMClockChangeSupportsVActive &&
- mode_lib->vba.MinActiveDRAMClockChangeMargin > 60 &&
- mode_lib->vba.PrefetchMode[mode_lib->vba.VoltageLevel][mode_lib->vba.maxMpcComb] == 0) {
+ mode_lib->vba.MinActiveDRAMClockChangeMargin > 60) {
mode_lib->vba.DRAMClockChangeWatermark += 25;

for (k = 0; k < mode_lib->vba.NumberOfActivePlanes; ++k) {
- if (mode_lib->vba.DRAMClockChangeWatermark >
- dml_max(mode_lib->vba.StutterEnterPlusExitWatermark, mode_lib->vba.UrgentWatermark))
- mode_lib->vba.MinTTUVBlank[k] += 25;
+ if (mode_lib->vba.PrefetchMode[mode_lib->vba.VoltageLevel][mode_lib->vba.maxMpcComb] == 0) {
+ if (mode_lib->vba.DRAMClockChangeWatermark >
+ dml_max(mode_lib->vba.StutterEnterPlusExitWatermark, mode_lib->vba.UrgentWatermark))
+ mode_lib->vba.MinTTUVBlank[k] += 25;
+ }
}

mode_lib->vba.DRAMClockChangeSupport[0][0] = dm_dram_clock_change_vactive;