drm/amd/display: reduce stack for dml32_CalculatePrefetchSchedule

Move stack variables to dummy structure.
Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>

drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_32.c

@@ -757,7 +757,9 @@ static void DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerforman
 			v->dummy_vars.DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerformanceCalculation.myPipe.BytePerPixelY = v->BytePerPixelY[k];
 			v->dummy_vars.DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerformanceCalculation.myPipe.BytePerPixelC = v->BytePerPixelC[k];
 			v->dummy_vars.DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerformanceCalculation.myPipe.ProgressiveToInterlaceUnitInOPP = mode_lib->vba.ProgressiveToInterlaceUnitInOPP;
-			v->ErrorResult[k] = dml32_CalculatePrefetchSchedule(v->dummy_vars.DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerformanceCalculation.HostVMInefficiencyFactor,
+			v->ErrorResult[k] = dml32_CalculatePrefetchSchedule(
+					&v->dummy_vars.dml32_CalculatePrefetchSchedule,
+					v->dummy_vars.DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerformanceCalculation.HostVMInefficiencyFactor,
 					&v->dummy_vars.DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerformanceCalculation.myPipe, v->DSCDelay[k],
 					mode_lib->vba.DPPCLKDelaySubtotal + mode_lib->vba.DPPCLKDelayCNVCFormater,
 					mode_lib->vba.DPPCLKDelaySCL,
@@ -3195,6 +3197,7 @@ void dml32_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_l
 
 					mode_lib->vba.NoTimeForPrefetch[i][j][k] =
 						dml32_CalculatePrefetchSchedule(
+							&v->dummy_vars.dml32_CalculatePrefetchSchedule,
 							v->dummy_vars.dml32_ModeSupportAndSystemConfigurationFull.HostVMInefficiencyFactor,
 							&v->dummy_vars.dml32_ModeSupportAndSystemConfigurationFull.myPipe,
 							mode_lib->vba.DSCDelayPerState[i][k],

drivers/gpu/drm/amd/display/dc/dml/dcn32/display_mode_vba_util_32.h

@@ -715,6 +715,7 @@ double dml32_CalculateExtraLatency(
 		unsigned int HostVMMaxNonCachedPageTableLevels);
 
 bool dml32_CalculatePrefetchSchedule(
+		struct dml32_CalculatePrefetchSchedule *st_vars,
 		double HostVMInefficiencyFactor,
 		DmlPipe *myPipe,
 		unsigned int DSCDelay,

drivers/gpu/drm/amd/display/dc/dml/display_mode_vba.h

@@ -247,6 +247,43 @@ struct dml32_CalculateWatermarksMALLUseAndDRAMSpeedChangeSupport {
 	unsigned int LBLatencyHidingSourceLinesC[DC__NUM_DPP__MAX];
 };
 
+struct dml32_CalculatePrefetchSchedule {
+	unsigned int DPPCycles, DISPCLKCycles;
+	double DSTTotalPixelsAfterScaler;
+	double LineTime;
+	double dst_y_prefetch_equ;
+	double prefetch_bw_oto;
+	double Tvm_oto;
+	double Tr0_oto;
+	double Tvm_oto_lines;
+	double Tr0_oto_lines;
+	double dst_y_prefetch_oto;
+	double TimeForFetchingMetaPTE;
+	double TimeForFetchingRowInVBlank;
+	double LinesToRequestPrefetchPixelData;
+	unsigned int HostVMDynamicLevelsTrips;
+	double trip_to_mem;
+	double Tvm_trips;
+	double Tr0_trips;
+	double Tvm_trips_rounded;
+	double Tr0_trips_rounded;
+	double Lsw_oto;
+	double Tpre_rounded;
+	double prefetch_bw_equ;
+	double Tvm_equ;
+	double Tr0_equ;
+	double Tdmbf;
+	double Tdmec;
+	double Tdmsks;
+	double prefetch_sw_bytes;
+	double bytes_pp;
+	double dep_bytes;
+	unsigned int max_vratio_pre;
+	double min_Lsw;
+	double Tsw_est1;
+	double Tsw_est3;
+};
+
 struct DISPCLKDPPCLKDCFCLKDeepSleepPrefetchParametersWatermarksAndPerformanceCalculation {
 	unsigned int dummy_integer_array[2][DC__NUM_DPP__MAX];
 	double dummy_single_array[2][DC__NUM_DPP__MAX];
@@ -321,6 +358,7 @@ struct dummy_vars {
 	struct dml32_CalculateSwathAndDETConfiguration dml32_CalculateSwathAndDETConfiguration;
 	struct dml32_CalculateVMRowAndSwath dml32_CalculateVMRowAndSwath;
 	struct dml32_CalculateWatermarksMALLUseAndDRAMSpeedChangeSupport dml32_CalculateWatermarksMALLUseAndDRAMSpeedChangeSupport;
+	struct dml32_CalculatePrefetchSchedule dml32_CalculatePrefetchSchedule;
 };
 
 struct vba_vars_st {