From bab9b5d3ce14c5b9cb55bd34da4851672e287467 Mon Sep 17 00:00:00 2001
From: NeoBrainX <NeoBrainX@gmail.com>
Date: Wed, 22 Aug 2012 01:01:47 +0200
Subject: [PATCH] FifoPlayer: Fix fifo log playback in dual-core mode.

---
 .../Core/Core/Src/FifoPlayer/FifoPlayer.cpp   | 42 ++++++++++++++++++-
 Source/Core/Core/Src/FifoPlayer/FifoPlayer.h  |  1 +
 2 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/Source/Core/Core/Src/FifoPlayer/FifoPlayer.cpp b/Source/Core/Core/Src/FifoPlayer/FifoPlayer.cpp
index ff90736fec..1873a91574 100644
--- a/Source/Core/Core/Src/FifoPlayer/FifoPlayer.cpp
+++ b/Source/Core/Core/Src/FifoPlayer/FifoPlayer.cpp
@@ -20,6 +20,7 @@
 
 #include "Common.h"
 #include "CoreTiming.h"
+#include "Thread.h"
 
 #include "HW/GPFifo.h"
 #include "HW/Memmap.h"
@@ -27,6 +28,7 @@
 #include "PowerPC/PowerPC.h"
 
 #include "BPMemory.h"
+#include "CommandProcessor.h"
 
 FifoPlayer::~FifoPlayer()
 {
@@ -94,7 +96,40 @@ bool FifoPlayer::Play()
 				if (m_EarlyMemoryUpdates && m_CurrentFrame == m_FrameRangeStart)
 					WriteAllMemoryUpdates();
 
-				WriteFrame(m_File->GetFrame(m_CurrentFrame), m_FrameInfo[m_CurrentFrame]);		
+				// Stop Fifo processing until we've written the new frame
+				WriteCP(CommandProcessor::CTRL_REGISTER, 0x10);  // disable read & breakpoints, enable GP link
+
+				// Write frame data
+				WriteFrame(m_File->GetFrame(m_CurrentFrame), m_FrameInfo[m_CurrentFrame]);
+
+				// Enable frame processing and break when done
+				u16 write_ptr_lo = ReadCP(CommandProcessor::FIFO_WRITE_POINTER_LO);
+				u16 write_ptr_hi = ReadCP(CommandProcessor::FIFO_WRITE_POINTER_HI);
+				WriteCP(CommandProcessor::FIFO_BP_LO, write_ptr_lo);
+				WriteCP(CommandProcessor::FIFO_BP_HI, write_ptr_hi);
+				WriteCP(CommandProcessor::CTRL_REGISTER, 0x13);  // enable read, breakpoints & GP link
+
+				// If necessary, wait until GP has reached the breakpoint to prevent fifo overflows
+				// TODO: Can this be done any better? Dual core mode is slower than single core mode even with these conditions..
+				if (m_CurrentFrame < m_FrameRangeEnd)
+				{
+					// Check if FIFO would be overflown when writing the next frame
+					u32 CPRWDistance = (ReadCP(CommandProcessor::FIFO_RW_DISTANCE_HI)<<16) | ReadCP(CommandProcessor::FIFO_RW_DISTANCE_LO);
+					CPRWDistance += m_File->GetFrame(m_CurrentFrame+1).fifoDataSize + CommandProcessor::GATHER_PIPE_SIZE;
+					u32 CPFifoBase = (ReadCP(CommandProcessor::FIFO_BASE_HI)<<16) | ReadCP(CommandProcessor::FIFO_BASE_LO);
+					u32 CPFifoEnd = (ReadCP(CommandProcessor::FIFO_END_HI)<<16) | ReadCP(CommandProcessor::FIFO_END_LO);
+
+					bool bWait = (CPRWDistance > CPFifoEnd - CPFifoBase);
+					while (bWait && (ReadCP(CommandProcessor::FIFO_READ_POINTER_LO) != write_ptr_lo ||
+									ReadCP(CommandProcessor::FIFO_READ_POINTER_HI) != write_ptr_hi))
+					{
+						Common::YieldCPU();
+						CoreTiming::Advance(); // Process scheduled events (esp. PixelEngine::SetFinish!)
+
+						if (PowerPC::GetState() == PowerPC::CPU_POWERDOWN)
+							break;
+					}
+				}
 
 				++m_CurrentFrame;
 			}
@@ -387,6 +422,11 @@ void FifoPlayer::LoadMemory()
 	FlushWGP();
 }
 
+u16 FifoPlayer::ReadCP(u32 address)
+{
+    return Memory::Read_U16(0xCC000000 | address);
+}
+
 void FifoPlayer::WriteCP(u32 address, u16 value)
 {
 	Memory::Write_U16(value, 0xCC000000 | address);
diff --git a/Source/Core/Core/Src/FifoPlayer/FifoPlayer.h b/Source/Core/Core/Src/FifoPlayer/FifoPlayer.h
index 9db6c0d980..838ac13f18 100644
--- a/Source/Core/Core/Src/FifoPlayer/FifoPlayer.h
+++ b/Source/Core/Core/Src/FifoPlayer/FifoPlayer.h
@@ -87,6 +87,7 @@ private:
 
 	void LoadMemory();
 
+	u16 ReadCP(u32 address);
 	void WriteCP(u32 address, u16 value);
 	void WritePI(u32 address, u32 value);