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

205 lines
5.4 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 <string.h>
#include "Setup.h"
#include "MemoryUtil.h"
#include "Thread.h"
#include "Atomic.h"
#include "OpcodeDecoding.h"
#include "Fifo.h"
extern u8* g_pVideoData;
volatile bool g_EFBAccessRequested = false;
namespace {
static volatile bool fifoStateRun = false;
static u8 *videoBuffer;
static Common::Event fifo_exit_event;
static Common::CriticalSection s_criticalFifo;
// STATE_TO_SAVE
static int size = 0;
} // namespace
void Fifo_DoState(PointerWrap &p)
{
s_criticalFifo.Enter();
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
s_criticalFifo.Leave();
}
void Fifo_Init()
{
videoBuffer = (u8*)AllocateMemoryPages(FIFO_SIZE);
fifo_exit_event.Init();
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];
}
// 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()
{
fifoStateRun = false;
fifo_exit_event.MsgWait();
fifo_exit_event.Shutdown();
}
// May be executed from any thread, even the graphics thread.
// Created to allow for self shutdown.
void Fifo_ExitLoopNonBlocking() {
fifoStateRun = false;
}
// 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);
if (size - pos > pos)
{
PanicAlert("FIFO out of bounds (sz = %i, at %08x)", size, pos);
}
memmove(&videoBuffer[0], &videoBuffer[pos], size - pos);
size -= pos;
g_pVideoData = FAKE_GetFifoStartPtr();
}
// Copy new video instructions to videoBuffer for future use in rendering the new picture
memcpy(videoBuffer + size, _uData, len);
size += len;
OpcodeDecoder_Run();
}
// Description: Main FIFO update loop
// Purpose: Keep the Core HW updated about the CPU-GPU distance
void Fifo_EnterLoop(const SVideoInitialize &video_initialize)
{
fifoStateRun = true;
SCPFifoStruct &_fifo = *video_initialize.pCPFifo;
s32 distToSend;
while (fifoStateRun)
{
video_initialize.pPeekMessages();
VideoFifo_CheckEFBAccess();
VideoFifo_CheckSwapRequest();
s_criticalFifo.Enter();
// check if we are able to run this buffer
if ((_fifo.bFF_GPReadEnable) && _fifo.CPReadWriteDistance && !(_fifo.bFF_BPEnable && _fifo.bFF_Breakpoint))
{
Common::AtomicStore(_fifo.CPReadIdle, 0);
while (_fifo.bFF_GPReadEnable && _fifo.CPReadWriteDistance)
{
if(!fifoStateRun)
break;
// Create pointer to video data and send it to the VideoPlugin
u32 readPtr = _fifo.CPReadPointer;
u8 *uData = video_initialize.pGetMemoryPointer(readPtr);
// if we are on BP mode we must send 32B chunks to Video plugin for BP checking
// TODO (mb2): test & check if MP1/MP2 realy need this now.
if (_fifo.bFF_BPEnable)
{
if (readPtr == _fifo.CPBreakpoint)
{
Common::AtomicStore(_fifo.bFF_Breakpoint, 1);
video_initialize.pUpdateInterrupts();
break;
}
distToSend = 32;
readPtr += 32;
if ( readPtr >= _fifo.CPEnd)
readPtr = _fifo.CPBase;
}
else
{
distToSend = _fifo.CPReadWriteDistance;
// send 1024B chunk max length to have better control over PeekMessages' period
distToSend = distToSend > 1024 ? 1024 : distToSend;
if ((distToSend + readPtr) >= _fifo.CPEnd) // TODO: better?
{
distToSend =_fifo.CPEnd - readPtr;
readPtr = _fifo.CPBase;
}
else
readPtr += distToSend;
}
// Execute new instructions found in uData
Fifo_SendFifoData(uData, distToSend);
Common::AtomicStore(_fifo.CPReadPointer, readPtr);
Common::AtomicAdd(_fifo.CPReadWriteDistance, -distToSend);
video_initialize.pPeekMessages();
VideoFifo_CheckEFBAccess();
VideoFifo_CheckSwapRequest();
}
Common::AtomicStore(_fifo.CPReadIdle, 1);
}
else
{
Common::YieldCPU();
}
s_criticalFifo.Leave();
}
fifo_exit_event.Set();
}