From 64299206d19938f74caaa5a0a0e1df571c376502 Mon Sep 17 00:00:00 2001
From: ayuanx <ayuanx@gmail.com>
Date: Tue, 15 Jun 2010 09:58:43 +0000
Subject: [PATCH] I was wrong on the CPEnd issue, which reveals CPBreakpoint >
 CPEnd is possible and that explains why some BPs could never be achieved
 before.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@5705 8ced0084-cf51-0410-be5f-012b33b47a6e
---
 Source/Core/Core/Src/HW/GPFifo.cpp            |  2 +-
 .../Core/VideoCommon/Src/CommandProcessor.cpp | 19 ++++++++++++++-----
 Source/Core/VideoCommon/Src/Fifo.cpp          | 10 +++++-----
 3 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/Source/Core/Core/Src/HW/GPFifo.cpp b/Source/Core/Core/Src/HW/GPFifo.cpp
index babeaa9320..80f48f8b9f 100644
--- a/Source/Core/Core/Src/HW/GPFifo.cpp
+++ b/Source/Core/Core/Src/HW/GPFifo.cpp
@@ -81,7 +81,7 @@ void STACKALIGN CheckGatherPipe()
 			m_gatherPipeCount -= GATHER_PIPE_SIZE;
 
 			// increase the CPUWritePointer
-			if (ProcessorInterface::Fifo_CPUWritePointer + GATHER_PIPE_SIZE >= ProcessorInterface::Fifo_CPUEnd)
+			if (ProcessorInterface::Fifo_CPUWritePointer >= ProcessorInterface::Fifo_CPUEnd)
 			{
 				curMem -= ProcessorInterface::Fifo_CPUWritePointer - ProcessorInterface::Fifo_CPUBase;
 				ProcessorInterface::Fifo_CPUWritePointer = ProcessorInterface::Fifo_CPUBase;
diff --git a/Source/Core/VideoCommon/Src/CommandProcessor.cpp b/Source/Core/VideoCommon/Src/CommandProcessor.cpp
index 617598eb1d..881ee910cd 100644
--- a/Source/Core/VideoCommon/Src/CommandProcessor.cpp
+++ b/Source/Core/VideoCommon/Src/CommandProcessor.cpp
@@ -158,7 +158,7 @@ void Init()
 
 	memset(&fifo,0,sizeof(fifo));
 	fifo.CPCmdIdle  = 1 ;
-	fifo.CPReadIdle = 1;
+	fifo.CPReadIdle = 1;	// We use it as UnderFlow flag now, otherwise we need a new volatile variable
 	fifo.bFF_Breakpoint = 0;
 
 	s_fifoIdleEvent.Init();
@@ -394,6 +394,12 @@ void Write16(const u16 _Value, const u32 _Address)
 			if (!tmpCtrl.BPEnable)
 				Common::AtomicStore(fifo.bFF_Breakpoint, false);
 
+			if (tmpCtrl.FifoUnderflowIntEnable)
+				Common::AtomicStore(fifo.CPReadIdle, false);
+
+			if (tmpCtrl.FifoOverflowIntEnable)
+				m_CPStatusReg.OverflowHiWatermark = false;
+
 			fifo.bFF_BPInt = tmpCtrl.BPInt;
 			fifo.bFF_BPEnable = tmpCtrl.BPEnable;
 			fifo.bFF_GPReadEnable = tmpCtrl.GPReadEnable;
@@ -560,10 +566,13 @@ void STACKALIGN GatherPipeBursted()
 	if (!m_CPCtrlReg.GPLinkEnable)
 		return;
 
+	_assert_msg_(COMMANDPROCESSOR, fifo.CPReadWriteDistance	< fifo.CPEnd - fifo.CPBase, "FIFO is overflown by GatherPipe !");
+
+
 	if (g_VideoInitialize.bOnThread)
 	{
 		// update the fifo-pointer
-        if (fifo.CPWritePointer + GATHER_PIPE_SIZE >= fifo.CPEnd)
+        if (fifo.CPWritePointer >= fifo.CPEnd)
 			fifo.CPWritePointer = fifo.CPBase;
         else
 		    fifo.CPWritePointer += GATHER_PIPE_SIZE;
@@ -611,7 +620,7 @@ void STACKALIGN GatherPipeBursted()
 	}
 	else
 	{
-		if (fifo.CPWritePointer + GATHER_PIPE_SIZE >= fifo.CPEnd)
+		if (fifo.CPWritePointer >= fifo.CPEnd)
 			fifo.CPWritePointer = fifo.CPBase;
         else
 		    fifo.CPWritePointer += GATHER_PIPE_SIZE;
@@ -636,7 +645,7 @@ void CatchUpGPU()
 	while (fifo.bFF_GPReadEnable && fifo.CPReadWriteDistance && (!fifo.bFF_BPEnable || (fifo.bFF_BPEnable && !fifo.bFF_Breakpoint)))
 	{
 		// check if we are on a breakpoint
-		if (fifo.bFF_BPEnable && fifo.CPReadPointer == fifo.CPBreakpoint)
+		if (fifo.bFF_BPEnable && ((fifo.CPReadPointer <= fifo.CPBreakpoint) && (fifo.CPReadPointer + 32 > fifo.CPBreakpoint)))
 		{
 			//_assert_msg_(POWERPC,0,"BP: %08x",fifo.CPBreakpoint);
 			fifo.bFF_Breakpoint = 1;
@@ -653,7 +662,7 @@ void CatchUpGPU()
 		LoadSSEState();
 
 		// increase the ReadPtr
-		if (fifo.CPReadPointer + 32 >= fifo.CPEnd)
+		if (fifo.CPReadPointer >= fifo.CPEnd)
 		{
 			fifo.CPReadPointer = fifo.CPBase;
 			// adjust, take care
diff --git a/Source/Core/VideoCommon/Src/Fifo.cpp b/Source/Core/VideoCommon/Src/Fifo.cpp
index 894224d6f5..ff31ec8dc3 100644
--- a/Source/Core/VideoCommon/Src/Fifo.cpp
+++ b/Source/Core/VideoCommon/Src/Fifo.cpp
@@ -163,7 +163,7 @@ void Fifo_EnterLoop(const SVideoInitialize &video_initialize)
 			// If we are in BP mode we only send 32B chunks to Video plugin for BP checking
 			if (_fifo.bFF_BPEnable)
 			{
-				if (readPtr == _fifo.CPBreakpoint)
+				if ((readPtr <= _fifo.CPBreakpoint) && (readPtr + 32 > _fifo.CPBreakpoint))
 				{
 					Common::AtomicStore(_fifo.bFF_Breakpoint, 1);
 					if (_fifo.bFF_BPInt)
@@ -173,7 +173,7 @@ void Fifo_EnterLoop(const SVideoInitialize &video_initialize)
 				}
 
 				distToSend = 32;
-				if (readPtr + 32 >= _fifo.CPEnd) 
+				if (readPtr >= _fifo.CPEnd) 
 					readPtr = _fifo.CPBase;
 				else
 					readPtr += 32;
@@ -184,9 +184,9 @@ void Fifo_EnterLoop(const SVideoInitialize &video_initialize)
 				distToSend = _fifo.CPReadWriteDistance;
 				// send 1024B chunk max length to have better control over PeekMessages' period
 				distToSend = distToSend > 1024 ? 1024 : distToSend;
-				if (readPtr + distToSend >= _fifo.CPEnd)
+				if (readPtr + distToSend >= _fifo.CPEnd + 32)
 				{
-					distToSend = _fifo.CPEnd - readPtr;
+					distToSend = _fifo.CPEnd + 32 - readPtr;
 					readPtr = _fifo.CPBase;
 				}
 				else
@@ -208,7 +208,7 @@ void Fifo_EnterLoop(const SVideoInitialize &video_initialize)
 			VideoFifo_CheckSwapRequest();
 		}
 
-		if (!_fifo.CPReadIdle && _fifo.CPReadWriteDistance <= _fifo.CPLoWatermark)
+		if (!_fifo.CPReadIdle && _fifo.CPReadWriteDistance < _fifo.CPLoWatermark)
 		{
 			Common::AtomicStore(_fifo.CPReadIdle, true);
 			CommandProcessor::UpdateInterruptsFromVideoPlugin();