drm/amd/display: Fix DSC slice and delay calculations

[why]
There are other factors that determine the number
of DSC slices. The slices should not be determined
in DML but retrieve the value calculated from driver.

[how]
Update the logic to determine DSC slice.
Make DSCDelay per display pipe.

Reviewed-by: Jun Lei <[e-mail]>
Acked-by: Zaeem Mohamed <[e-mail]>
Signed-off-by: Sung Joon Kim <[e-mail]>
Tested-by: Daniel Wheeler <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/dc/dml2/display_mode_core.c

···
 	dml_float_t DISPCLKDPPCLKDSCCLKDownSpreading,
 	dml_float_t DISPCLKRampingMargin,
 	dml_float_t DISPCLKDPPCLKVCOSpeed,
+	dml_uint_t NumberOfDSCSlices,
 
 	// Output
 	dml_bool_t *TotalAvailablePipesSupport,
···
 		dml_float_t DISPCLKDPPCLKDSCCLKDownSpreading,
 		dml_float_t DISPCLKRampingMargin,
 		dml_float_t DISPCLKDPPCLKVCOSpeed,
+		dml_uint_t NumberOfDSCSlices,
 
 		// Output
 		dml_bool_t *TotalAvailablePipesSupport,
···
 	*NumberOfDPP = 0;
 
 	if (!(Output == dml_hdmi || Output == dml_dp || Output == dml_edp) && (ODMUse == dml_odm_use_policy_combine_4to1 || (ODMUse == dml_odm_use_policy_combine_as_needed &&
-		(SurfaceRequiredDISPCLKWithODMCombineTwoToOne > StateDispclk || (DSCEnable && (HActive > 2 * MaximumPixelsPerLinePerDSCUnit)))))) {
+		(SurfaceRequiredDISPCLKWithODMCombineTwoToOne > StateDispclk || (DSCEnable && (HActive > 2 * MaximumPixelsPerLinePerDSCUnit)) || NumberOfDSCSlices > 8)))) {
 		if (TotalNumberOfActiveDPP + 4 <= MaxNumDPP) {
 			*ODMMode = dml_odm_mode_combine_4to1;
 			*RequiredDISPCLKPerSurface = SurfaceRequiredDISPCLKWithODMCombineFourToOne;
···
 		}
 	} else if (Output != dml_hdmi && (ODMUse == dml_odm_use_policy_combine_2to1 || (ODMUse == dml_odm_use_policy_combine_as_needed &&
 				((SurfaceRequiredDISPCLKWithoutODMCombine > StateDispclk && SurfaceRequiredDISPCLKWithODMCombineTwoToOne <= StateDispclk) ||
-				(DSCEnable && (HActive > MaximumPixelsPerLinePerDSCUnit)))))) {
+				(DSCEnable && (HActive > MaximumPixelsPerLinePerDSCUnit)) || (NumberOfDSCSlices <= 8 && NumberOfDSCSlices > 4))))) {
 		if (TotalNumberOfActiveDPP + 2 <= MaxNumDPP) {
 			*ODMMode = dml_odm_mode_combine_2to1;
 			*RequiredDISPCLKPerSurface = SurfaceRequiredDISPCLKWithODMCombineTwoToOne;
···
 
 	if (DSCEnabled == true && OutputBpp != 0) {
 		if (ODMMode == dml_odm_mode_combine_4to1) {
-			DSCDelayRequirement_val = 4 * (dscceComputeDelay(DSCInputBitPerComponent, OutputBpp, (dml_uint_t)(dml_ceil((dml_float_t) HActive / (dml_float_t) NumberOfDSCSlices, 1.0)),
-												(dml_uint_t) (NumberOfDSCSlices / 4.0), OutputFormat, Output) + dscComputeDelay(OutputFormat, Output));
+			DSCDelayRequirement_val = dscceComputeDelay(DSCInputBitPerComponent, OutputBpp, (dml_uint_t)(dml_ceil((dml_float_t) HActive / (dml_float_t) NumberOfDSCSlices, 1.0)),
+												(dml_uint_t) (NumberOfDSCSlices / 4.0), OutputFormat, Output) + dscComputeDelay(OutputFormat, Output);
 		} else if (ODMMode == dml_odm_mode_combine_2to1) {
-			DSCDelayRequirement_val = 2 * (dscceComputeDelay(DSCInputBitPerComponent, OutputBpp, (dml_uint_t)(dml_ceil((dml_float_t) HActive / (dml_float_t) NumberOfDSCSlices, 1.0)),
-												(dml_uint_t) (NumberOfDSCSlices / 2.0), OutputFormat, Output) + dscComputeDelay(OutputFormat, Output));
+			DSCDelayRequirement_val = dscceComputeDelay(DSCInputBitPerComponent, OutputBpp, (dml_uint_t)(dml_ceil((dml_float_t) HActive / (dml_float_t) NumberOfDSCSlices, 1.0)),
+												(dml_uint_t) (NumberOfDSCSlices / 2.0), OutputFormat, Output) + dscComputeDelay(OutputFormat, Output);
 		} else {
 			DSCDelayRequirement_val = dscceComputeDelay(DSCInputBitPerComponent, OutputBpp, (dml_uint_t)((dml_float_t) dml_ceil(HActive / (dml_float_t) NumberOfDSCSlices, 1.0)),
 										NumberOfDSCSlices, OutputFormat, Output) + dscComputeDelay(OutputFormat, Output);
···
 
 	/*Number Of DSC Slices*/
 	for (k = 0; k < mode_lib->ms.num_active_planes; ++k) {
-		if (mode_lib->ms.cache_display_cfg.plane.BlendingAndTiming[k] == k) {
-			if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 4800) {
-				mode_lib->ms.support.NumberOfDSCSlices[k] = (dml_uint_t)(dml_ceil(mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] / 600, 4));
-			} else if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 2400) {
-				mode_lib->ms.support.NumberOfDSCSlices[k] = 8;
-			} else if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 1200) {
-				mode_lib->ms.support.NumberOfDSCSlices[k] = 4;
-			} else if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 340) {
-				mode_lib->ms.support.NumberOfDSCSlices[k] = 2;
-			} else {
-				mode_lib->ms.support.NumberOfDSCSlices[k] = 1;
+		if (mode_lib->ms.cache_display_cfg.plane.BlendingAndTiming[k] == k &&
+			mode_lib->ms.cache_display_cfg.output.DSCEnable[k] != dml_dsc_disable) {
+			mode_lib->ms.support.NumberOfDSCSlices[k] = mode_lib->ms.cache_display_cfg.output.DSCSlices[k];
+
+			if (mode_lib->ms.support.NumberOfDSCSlices[k] == 0) {
+				if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 4800) {
+					mode_lib->ms.support.NumberOfDSCSlices[k] = (dml_uint_t)(dml_ceil(mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] / 600, 4));
+				} else if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 2400) {
+					mode_lib->ms.support.NumberOfDSCSlices[k] = 8;
+				} else if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 1200) {
+					mode_lib->ms.support.NumberOfDSCSlices[k] = 4;
+				} else if (mode_lib->ms.cache_display_cfg.output.PixelClockBackEnd[k] > 340) {
+					mode_lib->ms.support.NumberOfDSCSlices[k] = 2;
+				} else {
+					mode_lib->ms.support.NumberOfDSCSlices[k] = 1;
+				}
 			}
 		} else {
-			mode_lib->ms.support.NumberOfDSCSlices[k] = 0;
+			mode_lib->ms.support.NumberOfDSCSlices[k] = 1;
 		}
 	}
 
···
 					mode_lib->ms.soc.dcn_downspread_percent,
 					mode_lib->ms.ip.dispclk_ramp_margin_percent,
 					mode_lib->ms.soc.dispclk_dppclk_vco_speed_mhz,
+					mode_lib->ms.support.NumberOfDSCSlices[k],
 
 					/* Output */
 					&s->TotalAvailablePipesSupportNoDSC,
···
 					mode_lib->ms.soc.dcn_downspread_percent,
 					mode_lib->ms.ip.dispclk_ramp_margin_percent,
 					mode_lib->ms.soc.dispclk_dppclk_vco_speed_mhz,
+					mode_lib->ms.support.NumberOfDSCSlices[k],
 
 					/* Output */
 					&s->TotalAvailablePipesSupportDSC,

drivers/gpu/drm/amd/display/dc/dml2/display_mode_core_structs.h

···
 	dml_uint_t AudioSampleRate[__DML_NUM_PLANES__];
 	dml_uint_t AudioSampleLayout[__DML_NUM_PLANES__];
 	dml_bool_t OutputDisabled[__DML_NUM_PLANES__];
+	dml_uint_t DSCSlices[__DML_NUM_PLANES__];
 }; // dml_timing_cfg_st;
 
 /// @brief Writeback Setting

drivers/gpu/drm/amd/display/dc/dml2/dml2_translation_helper.c

···
 	out->DSCEnable[location] = (enum dml_dsc_enable)in->timing.flags.DSC;
 	out->OutputLinkDPLanes[location] = 4; // As per code in dcn20_resource.c
 	out->DSCInputBitPerComponent[location] = 12; // As per code in dcn20_resource.c
+	out->DSCSlices[location] = in->timing.dsc_cfg.num_slices_h;
 
 	switch (in->signal) {
 	case SIGNAL_TYPE_DISPLAY_PORT_MST: