- FIX RE0 GFX fifo errors :D

- This game read the CPRead pointer when the GP is processing data and after detach the fifo  and attach again an use this pointer for continue, so implement fifo.SafeCPReadPointer pointer.
- fifo.SafeCPReadPointer is updated when (FAKE_GetFifoEndPtr() - g_pVideoData) == 0) to have a pointer without GFX Commands Cut in the beginning of 32 block.
- Reset video buffer when the CPReadWriteDistance is written by the software.
- This commit is experimental please test a lot your games.


git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@7165 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/Common/Src/VideoBackendBase.h

@@ -49,7 +49,7 @@ struct SCPFifoStruct
 	volatile u32 CPWritePointer;
 	volatile u32 CPReadPointer;
 	volatile u32 CPBreakpoint;
-
+	volatile u32 SafeCPReadPointer;
 	// Super Monkey Ball Adventure require this.
 	// Because the read&check-PEToken-loop stays in its JITed block I suppose.
 	// So no possiblity to ack the Token irq by the scheduler until some sort of PPC watchdog do its mess.

Source/Core/VideoCommon/Src/CommandProcessor.cpp

@@ -284,13 +284,19 @@ void Read16(u16& _rReturnValue, const u32 _Address)
 		return;
 
 	case FIFO_READ_POINTER_LO:
+		if (IsOnThread())
+			_rReturnValue = ReadLow (fifo.SafeCPReadPointer);
+		else
 			_rReturnValue = ReadLow (fifo.CPReadPointer);
 		// hack: CPU will always believe fifo is empty and on idle
 		//_rReturnValue = ReadLow (fifo.CPWritePointer);
 		DEBUG_LOG(COMMANDPROCESSOR, "read FIFO_READ_POINTER_LO : %04x", _rReturnValue);
 		return;
 	case FIFO_READ_POINTER_HI:
-		_rReturnValue = ReadHigh(fifo.CPReadPointer);
+		if (IsOnThread())
+			_rReturnValue = ReadHigh (fifo.SafeCPReadPointer);
+		else
+			_rReturnValue = ReadHigh (fifo.CPReadPointer);
 		// hack: CPU will always believe fifo is empty and on idle
 	    //_rReturnValue = ReadHigh(fifo.CPWritePointer);
 		DEBUG_LOG(COMMANDPROCESSOR, "read FIFO_READ_POINTER_HI : %04x", _rReturnValue);
@@ -614,8 +620,11 @@ void Write16(const u16 _Value, const u32 _Address)
 		{
 			GPFifo::ResetGatherPipe();
 			ResetVideoBuffer();
-			IncrementCheckContextId();
+		}else
+		{
+			ResetVideoBuffer();		
 		}
+		IncrementCheckContextId();
 		DEBUG_LOG(COMMANDPROCESSOR,"try to write to FIFO_RW_DISTANCE_LO : %04x", _Value);
 		break;
 

Source/Core/VideoCommon/Src/Fifo.cpp

@@ -169,7 +169,8 @@ void Fifo_EnterLoop()
 
 			Common::AtomicStore(_fifo.CPReadPointer, readPtr);
 			Common::AtomicAdd(_fifo.CPReadWriteDistance, -distToSend);						
-		    			
+			if((FAKE_GetFifoEndPtr() - g_pVideoData) == 0)
+				Common::AtomicStore(_fifo.SafeCPReadPointer, _fifo.CPReadPointer);
 			CommandProcessor::SetStatus();
 		
 			// This call is pretty important in DualCore mode and must be called in the FIFO Loop.