From: Leo Ma hanghong.ma@amd.com
[ Upstream commit 735688eb905db529efea0c78466fccc1461c3fde ]
[Why] Screen underflows happen on 175hz timing for 3 plane overlay case.
[How] Based on dst y prefetch value clamp to equ or oto for bandwidth calculation.
Reviewed-by: Dillon Varone dillon.varone@amd.com Acked-by: Alex Hung alex.hung@amd.com Signed-off-by: Leo Ma hanghong.ma@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../amd/display/dc/dml/dcn32/display_mode_vba_util_32.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c index a50e7f4dce421..f74e5fc8218f5 100644 --- a/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c +++ b/drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.c @@ -3459,6 +3459,7 @@ bool dml32_CalculatePrefetchSchedule( double TimeForFetchingMetaPTE = 0; double TimeForFetchingRowInVBlank = 0; double LinesToRequestPrefetchPixelData = 0; + double LinesForPrefetchBandwidth = 0; unsigned int HostVMDynamicLevelsTrips; double trip_to_mem; double Tvm_trips; @@ -3888,11 +3889,15 @@ bool dml32_CalculatePrefetchSchedule( TimeForFetchingMetaPTE = Tvm_oto; TimeForFetchingRowInVBlank = Tr0_oto; *PrefetchBandwidth = prefetch_bw_oto; + /* Clamp to oto for bandwidth calculation */ + LinesForPrefetchBandwidth = dst_y_prefetch_oto; } else { *DestinationLinesForPrefetch = dst_y_prefetch_equ; TimeForFetchingMetaPTE = Tvm_equ; TimeForFetchingRowInVBlank = Tr0_equ; *PrefetchBandwidth = prefetch_bw_equ; + /* Clamp to equ for bandwidth calculation */ + LinesForPrefetchBandwidth = dst_y_prefetch_equ; }
*DestinationLinesToRequestVMInVBlank = dml_ceil(4.0 * TimeForFetchingMetaPTE / LineTime, 1.0) / 4.0; @@ -3900,7 +3905,7 @@ bool dml32_CalculatePrefetchSchedule( *DestinationLinesToRequestRowInVBlank = dml_ceil(4.0 * TimeForFetchingRowInVBlank / LineTime, 1.0) / 4.0;
- LinesToRequestPrefetchPixelData = *DestinationLinesForPrefetch - + LinesToRequestPrefetchPixelData = LinesForPrefetchBandwidth - *DestinationLinesToRequestVMInVBlank - 2 * *DestinationLinesToRequestRowInVBlank;
#ifdef __DML_VBA_DEBUG__