dolphin/Source/Core/VideoCommon/Src/Fifo.cpp

221 lines
5.9 KiB
C++

// Copyright (C) 2003 Dolphin Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
#include "VideoConfig.h"
#include "Setup.h"
#include "MemoryUtil.h"
#include "Thread.h"
#include "Atomic.h"
#include "OpcodeDecoding.h"
#include "CommandProcessor.h"
#include "ChunkFile.h"
#include "Fifo.h"
#include "HW/Memmap.h"
volatile bool g_bSkipCurrentFrame = false;
volatile bool g_EFBAccessRequested = false;
extern u8* g_pVideoData;
namespace
{
static volatile bool fifoStateRun = false;
static volatile bool EmuRunning = false;
static u8 *videoBuffer;
// STATE_TO_SAVE
static int size = 0;
} // namespace
void Fifo_DoState(PointerWrap &p)
{
CommandProcessor::FifoCriticalEnter();
p.DoArray(videoBuffer, FIFO_SIZE);
p.Do(size);
int pos = (int)(g_pVideoData - videoBuffer); // get offset
p.Do(pos); // read or write offset (depends on the mode afaik)
g_pVideoData = &videoBuffer[pos]; // overwrite g_pVideoData -> expected no change when load ss and change when save ss
CommandProcessor::FifoCriticalLeave();
}
void Fifo_Init()
{
videoBuffer = (u8*)AllocateMemoryPages(FIFO_SIZE);
fifoStateRun = false;
}
void Fifo_Shutdown()
{
if (fifoStateRun) PanicAlert("Fifo shutting down while active");
FreeMemoryPages(videoBuffer, FIFO_SIZE);
}
u8* FAKE_GetFifoStartPtr()
{
return videoBuffer;
}
u8* FAKE_GetFifoEndPtr()
{
return &videoBuffer[size];
}
void Fifo_SetRendering(bool enabled)
{
g_bSkipCurrentFrame = !enabled;
}
// Executed from another thread, no the graphics thread!
// Basically, all it does is set a flag so that the loop will eventually exit, then
// waits for the event to be set, which happens when the loop does exit.
// If we look stuck in here, then the video thread is stuck in something and won't exit
// the loop. Switch to the video thread and investigate.
void Fifo_ExitLoop()
{
Fifo_ExitLoopNonBlocking();
EmuRunning = true;
}
// May be executed from any thread, even the graphics thread.
// Created to allow for self shutdown.
void Fifo_ExitLoopNonBlocking()
{
// This should break the wait loop in CPU thread
CommandProcessor::fifo.bFF_GPReadEnable = false;
CommandProcessor::SetFifoIdleFromVideoPlugin();
// Terminate GPU thread loop
fifoStateRun = false;
EmuRunning = true;
}
void Fifo_RunLoop(bool run)
{
EmuRunning = run;
}
// Description: Fifo_EnterLoop() sends data through this function.
void Fifo_SendFifoData(u8* _uData, u32 len)
{
if (size + len >= FIFO_SIZE)
{
int pos = (int)(g_pVideoData - videoBuffer);
size -= pos;
if (size + len > FIFO_SIZE)
{
PanicAlert("FIFO out of bounds (sz = %i, at %08x)", size, pos);
}
memmove(&videoBuffer[0], &videoBuffer[pos], size);
g_pVideoData = videoBuffer;
}
// Copy new video instructions to videoBuffer for future use in rendering the new picture
memcpy(videoBuffer + size, _uData, len);
size += len;
}
void ResetVideoBuffer()
{
g_pVideoData = videoBuffer;
size = 0;
}
// Description: Main FIFO update loop
// Purpose: Keep the Core HW updated about the CPU-GPU distance
void Fifo_EnterLoop()
{
fifoStateRun = true;
SCPFifoStruct &_fifo = CommandProcessor::fifo;
s32 distToSend;
while (fifoStateRun)
{
g_video_backend->PeekMessages();
VideoFifo_CheckAsyncRequest();
// check if we are able to run this buffer
CommandProcessor::SetStatus();
while (!CommandProcessor::interruptWaiting && _fifo.bFF_GPReadEnable &&
_fifo.CPReadWriteDistance && (!AtBreakpoint() || CommandProcessor::OnOverflow))
{
// while the FIFO is processing data we activate this for sync with emulator thread.
CommandProcessor::isFifoBusy = true;
if (!fifoStateRun) break;
CommandProcessor::FifoCriticalEnter();
// Create pointer to video data and send it to the VideoPlugin
u32 readPtr = _fifo.CPReadPointer;
u8 *uData = Memory::GetPointer(readPtr);
distToSend = 32;
if (readPtr == _fifo.CPEnd)
readPtr = _fifo.CPBase;
else
readPtr += 32;
_assert_msg_(COMMANDPROCESSOR, (s32)_fifo.CPReadWriteDistance - distToSend >= 0 ,
"Negative fifo.CPReadWriteDistance = %i in FIFO Loop !\nThat can produce inestabilty in the game. Please report it.", _fifo.CPReadWriteDistance - distToSend);
// Execute new instructions found in uData
Fifo_SendFifoData(uData, distToSend);
OpcodeDecoder_Run(g_bSkipCurrentFrame);
Common::AtomicStore(_fifo.CPReadPointer, readPtr);
Common::AtomicAdd(_fifo.CPReadWriteDistance, -distToSend);
CommandProcessor::SetStatus();
CommandProcessor::FifoCriticalLeave();
// This call is pretty important in DualCore mode and must be called in the FIFO Loop.
// If we don't, s_swapRequested or s_efbAccessRequested won't be set to false
// leading the CPU thread to wait in Video_BeginField or Video_AccessEFB thus slowing things down.
VideoFifo_CheckAsyncRequest();
}
CommandProcessor::isFifoBusy = false;
CommandProcessor::SetFifoIdleFromVideoPlugin();
if (EmuRunning)
Common::YieldCPU();
else
{
// While the emu is paused, we still handle async request such as Savestates then sleep.
while (!EmuRunning)
{
g_video_backend->PeekMessages();
VideoFifo_CheckAsyncRequest();
Common::SleepCurrentThread(10);
}
}
}
}
bool AtBreakpoint()
{
SCPFifoStruct &_fifo = CommandProcessor::fifo;
return _fifo.bFF_BPEnable && (_fifo.CPReadPointer == _fifo.CPBreakpoint);
}