IPU: Set DMA to only transfer on request (or reset)

pcsx2/IPU/IPU.cpp

@@ -296,7 +296,7 @@ void ipuSoftReset()
 	ipu_cmd.clear();
 	ipuRegs.cmd.BUSY = 0;
 	ipuRegs.cmd.DATA = 0; // required for Enthusia - Professional Racing after fix, or will freeze at start of next video.
-
+	IPU1Status.DataRequested = true;
 	memzero(g_BP);
 	hwIntcIrq(INTC_IPU); // required for FightBox
 }
@@ -363,14 +363,12 @@ __fi bool ipuWrite64(u32 mem, u64 value)
 
 static void ipuBCLR(u32 val)
 {
-	// The Input FIFO shouldn't be cleared when the DMA is running, however if it is the DMA should drain
-	// as it is constantly fighting it....
-	while(ipu1ch.chcr.STR)
-	{
-		ipu_fifo.in.clear();
+	if (ipu1ch.chcr.STR && g_BP.IFC < 8 && IPU1Status.DataRequested)
 		ipu1Interrupt();
-	}
-	
+
+	if(!ipu1ch.chcr.STR)
+		psHu32(DMAC_STAT) &= ~(1 << DMAC_TO_IPU);
+
 	ipu_fifo.in.clear();
 
 	memzero(g_BP);
@@ -878,6 +876,12 @@ __fi void IPUCMD_WRITE(u32 val)
 			ipuBCLR(val);
 			hwIntcIrq(INTC_IPU); //DMAC_TO_IPU
 			ipuRegs.ctrl.BUSY = 0;
+
+			IPU1Status.DataRequested = true;
+			if (ipu1ch.chcr.STR && cpuRegs.eCycle[4] == 0x9999)
+			{
+				CPU_INT(DMAC_TO_IPU, 32);
+			}
 			return;
 
 		case SCE_IPU_SETTH:
@@ -1005,10 +1009,4 @@ __noinline void IPUWorker()
 	ipuRegs.ctrl.BUSY = 0;
 	//ipu_cmd.current = 0xffffffff;
 	hwIntcIrq(INTC_IPU);
-
-	// Fill the FIFO ready for the next command
-	if (ipu1ch.chcr.STR && cpuRegs.eCycle[4] == 0x9999)
-	{
-		CPU_INT(DMAC_TO_IPU, 32);
-	}
 }

pcsx2/IPU/IPU.h

@@ -16,6 +16,7 @@
 #pragma once
 
 #include "IPU_Fifo.h"
+#include "IPUdma.h"
 
 #define ipumsk( src ) ( (src) & 0xff )
 #define ipucase( src ) case ipumsk(src)

pcsx2/IPU/IPU_Fifo.cpp

@@ -85,11 +85,12 @@ int IPU_Fifo_Input::write(u32* pMem, int size)
 int IPU_Fifo_Input::read(void *value)
 {
 	// wait until enough data to ensure proper streaming.
-	if (g_BP.IFC < 3)
+	if (g_BP.IFC <= 1)
 	{
 		// IPU FIFO is empty and DMA is waiting so lets tell the DMA we are ready to put data in the FIFO
 		if(cpuRegs.eCycle[4] == 0x9999)
 		{
+			IPU1Status.DataRequested = true;
 			CPU_INT( DMAC_TO_IPU, 32 );
 		}
 

pcsx2/IPU/IPUdma.cpp

@@ -19,7 +19,7 @@
 #include "IPU/IPUdma.h"
 #include "mpeg2lib/Mpeg.h"
 
-static IPUStatus IPU1Status;
+IPUStatus IPU1Status;
 static tIPU_DMA g_nDMATransfer;
 
 void ipuDmaReset()
@@ -119,6 +119,13 @@ int IPU1dma()
 		return 0;
 	}
 
+	if (IPU1Status.DataRequested == false)
+	{
+		cpuRegs.eCycle[4] = 0x9999;
+		return 0;
+	}
+	
+
 	IPU_LOG("IPU1 DMA Called QWC %x Finished %d In Progress %d tadr %x", ipu1ch.qwc, IPU1Status.DMAFinished, IPU1Status.InProgress, ipu1ch.tadr);
 
 	switch(IPU1Status.DMAMode)
@@ -174,16 +181,27 @@ int IPU1dma()
 	}
 
 	//Do this here to prevent double settings on Chain DMA's
-	if(totalqwc > 0 || ipu1ch.qwc == 0)
+	if(totalqwc == 0 || (IPU1Status.DMAFinished && !IPU1Status.InProgress))
 	{
-		IPU_INT_TO(totalqwc * BIAS);
-		IPUProcessInterrupt();
+		totalqwc = std::min(4, totalqwc);
+		IPU_INT_TO(4);
 	}
 	else 
 	{
-		cpuRegs.eCycle[4] = 0x9999;//IPU_INT_TO(2048);
+		
+		if (g_BP.IFC == 8)
+		{
+			IPU1Status.DataRequested = false;
+			cpuRegs.eCycle[4] = 0x9999;//IPU_INT_TO(2048);
+		}
+		else
+		{
+			IPU_INT_TO(totalqwc*BIAS);
+		}
 	}
 
+	IPUProcessInterrupt();
+
 	IPU_LOG("Completed Call IPU1 DMA QWC Remaining %x Finished %d In Progress %d tadr %x", ipu1ch.qwc, IPU1Status.DMAFinished, IPU1Status.InProgress, ipu1ch.tadr);
 	return totalqwc;
 }
@@ -296,7 +314,10 @@ __fi void dmaIPU1() // toIPU
 		}
 
 		IPU1Status.DMAMode = DMA_MODE_CHAIN;
-		IPU1dma();
+		if(ipuRegs.ctrl.BUSY || IPU1Status.DataRequested)
+			IPU1dma();
+		else
+			cpuRegs.eCycle[4] = 0x9999;
 	}
 	else //Normal Mode
 	{
@@ -304,7 +325,10 @@ __fi void dmaIPU1() // toIPU
 			IPU1Status.InProgress = true;
 			IPU1Status.DMAFinished = true;
 			IPU1Status.DMAMode = DMA_MODE_NORMAL;
-			IPU1dma();
+			if (ipuRegs.ctrl.BUSY || IPU1Status.DataRequested)
+				IPU1dma();
+			else
+				cpuRegs.eCycle[4] = 0x9999;
 	}
 }
 

pcsx2/IPU/IPUdma.h

@@ -29,6 +29,7 @@ struct IPUStatus {
 	bool stalled;
 	u8 ChainMode;
 	u32 NextMem;
+	bool DataRequested;
 };
 
 #define DMA_MODE_NORMAL 0
@@ -91,3 +92,4 @@ extern void IPU0dma();
 extern int IPU1dma();
 
 extern void ipuDmaReset();
+extern IPUStatus IPU1Status;