dolphin/Source/Core/VideoCommon/Fifo.h

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// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.
#pragma once
#include "Common/CommonTypes.h"
#include "VideoCommon/VideoBackendBase.h"
class PointerWrap;
#define FIFO_SIZE (2*1024*1024)
extern bool g_bSkipCurrentFrame;
Add the 'desynced GPU thread' mode. It's a relatively big commit (less big with -w), but it's hard to test any of this separately... The basic problem is that in netplay or movies, the state of the CPU must be deterministic, including when the game receives notification that the GPU has processed FIFO data. Dual core mode notifies the game whenever the GPU thread actually gets around to doing the work, so it isn't deterministic. Single core mode is because it notifies the game 'instantly' (after processing the data synchronously), but it's too slow for many systems and games. My old dc-netplay branch worked as follows: everything worked as normal except the state of the CP registers was a lie, and the CPU thread only delivered results when idle detection triggered (waiting for the GPU if they weren't ready at that point). Usually, a game is idle iff all the work for the frame has been done, except for a small amount of work depending on the GPU result, so neither the CPU or the GPU waiting on the other affected performance much. However, it's possible that the game could be waiting for some earlier interrupt, and any of several games which, for whatever reason, never went into a detectable idle (even when I tried to improve the detection) would never receive results at all. (The current method should have better compatibility, but it also has slightly higher overhead and breaks some other things, so I want to reimplement this, hopefully with less impact on the code, in the future.) With this commit, the basic idea is that the CPU thread acts as if the work has been done instantly, like single core mode, but actually hands it off asynchronously to the GPU thread (after backing up some data that the game might change in memory before it's actually done). Since the work isn't done, any feedback from the GPU to the CPU, such as real XFB/EFB copies (virtual are OK), EFB pokes, performance queries, etc. is broken; but most games work with these options disabled, and there is no need to try to detect what the CPU thread is doing. Technically: when the flag g_use_deterministic_gpu_thread (currently stuck on) is on, the CPU thread calls RunGpu like in single core mode. This function synchronously copies the data from the FIFO to the internal video buffer and updates the CP registers, interrupts, etc. However, instead of the regular ReadDataFromFifo followed by running the opcode decoder, it runs ReadDataFromFifoOnCPU -> OpcodeDecoder_Preprocess, which relatively quickly scans through the FIFO data, detects SetFinish calls etc., which are immediately fired, and saves certain associated data from memory (e.g. display lists) in AuxBuffers (a parallel stream to the main FIFO, which is a bit slow at the moment), before handing the data off to the GPU thread to actually render. That makes up the bulk of this commit. In various circumstances, including the aforementioned EFB pokes and performance queries as well as swap requests (i.e. the end of a frame - we don't want the CPU potentially pumping out frames too quickly and the GPU falling behind*), SyncGPU is called to wait for actual completion. The overhead mainly comes from OpcodeDecoder_Preprocess (which is, again, synchronous), as well as the actual copying. Currently, display lists and such are escrowed from main memory even though they usually won't change over the course of a frame, and textures are not even though they might, resulting in a small chance of graphical glitches. When the texture locking (i.e. fault on write) code lands, I can make this all correct and maybe a little faster. * This suggests an alternate determinism method of just delaying results until a short time before the end of each frame. For all I know this might mostly work - I haven't tried it - but if any significant work hinges on the competion of render to texture etc., the frame will be missed.
2014-08-27 20:56:19 -06:00
// This could be in SCoreStartupParameter, but it depends on multiple settings
// and can change at runtime.
extern bool g_use_deterministic_gpu_thread;
extern std::atomic<u8*> g_video_buffer_write_ptr_xthread;
extern u8* g_video_buffer_pp_read_ptr;
BIG FIFO Commit PART 1! Sometimes you need to write everything from 0, so 10 days later Ive rewrited some parts of the FIFO in Dual Core mode. Is pending use the same code for SC mode. - Improved the GP Register Status: now this is all the time from the fifo loop. - Improved the Interrupts manage: 1) Removed All UpdateInturrupts from CommandProcessor Writes and Read. 2) now the CP interrupts are schedule from the video thread and the fifo loop waiting until this happens 3) considering Inmediate mode for the CP interrupts 3) Implemented Interrupt CP Cache State 4) Implemented only Overflow interrupt in GatherPipeCheck because this need to be detected quickly. - Implemented Overflow handling like a real HW, when Hiwatermark interrupt happens this write ClearRegister with True en HI and False in LO (FifoIntReset) after that a Control Register is writed and the FIFO is processed to LO Watermark. - Removed all ugly code from LO and HI watermark manage - Removed all ugly code from BP manage - Change >= by == in the BP clauses - Removed speed hack (1024 chunk) for better GP Status Control. - Commented GXSetGPFifo very soon hack - Commented FackWatchDog hack - Commented FIFO_RW_DISTANCE = WritePointer hack This is the beginning and the base for the future., If this broke your favorite game my apologize, only report this and will try solve it. If you have a Overflown don't worry, I've implemented the real solution code using the Overflow Interruption only need continue working for a perfect protection. Why I did it? Because is preferable a accurate and clean fifo instead hack y fifo for improve that. Thanks to DONKO for you awesome Video Plug in and skid for the chatting. PD: I have 7-10 fps more in the star fox video. bye :P git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@6554 8ced0084-cf51-0410-be5f-012b33b47a6e
2010-12-11 05:42:55 -07:00
void Fifo_Init();
void Fifo_Shutdown();
2014-07-08 06:29:26 -06:00
u8* GetVideoBufferStartPtr();
u8* GetVideoBufferEndPtr();
void Fifo_DoState(PointerWrap &f);
void Fifo_PauseAndLock(bool doLock, bool unpauseOnUnlock);
void Fifo_UpdateWantDeterminism(bool want);
Add the 'desynced GPU thread' mode. It's a relatively big commit (less big with -w), but it's hard to test any of this separately... The basic problem is that in netplay or movies, the state of the CPU must be deterministic, including when the game receives notification that the GPU has processed FIFO data. Dual core mode notifies the game whenever the GPU thread actually gets around to doing the work, so it isn't deterministic. Single core mode is because it notifies the game 'instantly' (after processing the data synchronously), but it's too slow for many systems and games. My old dc-netplay branch worked as follows: everything worked as normal except the state of the CP registers was a lie, and the CPU thread only delivered results when idle detection triggered (waiting for the GPU if they weren't ready at that point). Usually, a game is idle iff all the work for the frame has been done, except for a small amount of work depending on the GPU result, so neither the CPU or the GPU waiting on the other affected performance much. However, it's possible that the game could be waiting for some earlier interrupt, and any of several games which, for whatever reason, never went into a detectable idle (even when I tried to improve the detection) would never receive results at all. (The current method should have better compatibility, but it also has slightly higher overhead and breaks some other things, so I want to reimplement this, hopefully with less impact on the code, in the future.) With this commit, the basic idea is that the CPU thread acts as if the work has been done instantly, like single core mode, but actually hands it off asynchronously to the GPU thread (after backing up some data that the game might change in memory before it's actually done). Since the work isn't done, any feedback from the GPU to the CPU, such as real XFB/EFB copies (virtual are OK), EFB pokes, performance queries, etc. is broken; but most games work with these options disabled, and there is no need to try to detect what the CPU thread is doing. Technically: when the flag g_use_deterministic_gpu_thread (currently stuck on) is on, the CPU thread calls RunGpu like in single core mode. This function synchronously copies the data from the FIFO to the internal video buffer and updates the CP registers, interrupts, etc. However, instead of the regular ReadDataFromFifo followed by running the opcode decoder, it runs ReadDataFromFifoOnCPU -> OpcodeDecoder_Preprocess, which relatively quickly scans through the FIFO data, detects SetFinish calls etc., which are immediately fired, and saves certain associated data from memory (e.g. display lists) in AuxBuffers (a parallel stream to the main FIFO, which is a bit slow at the moment), before handing the data off to the GPU thread to actually render. That makes up the bulk of this commit. In various circumstances, including the aforementioned EFB pokes and performance queries as well as swap requests (i.e. the end of a frame - we don't want the CPU potentially pumping out frames too quickly and the GPU falling behind*), SyncGPU is called to wait for actual completion. The overhead mainly comes from OpcodeDecoder_Preprocess (which is, again, synchronous), as well as the actual copying. Currently, display lists and such are escrowed from main memory even though they usually won't change over the course of a frame, and textures are not even though they might, resulting in a small chance of graphical glitches. When the texture locking (i.e. fault on write) code lands, I can make this all correct and maybe a little faster. * This suggests an alternate determinism method of just delaying results until a short time before the end of each frame. For all I know this might mostly work - I haven't tried it - but if any significant work hinges on the competion of render to texture etc., the frame will be missed.
2014-08-27 20:56:19 -06:00
// Used for diagnostics.
enum SyncGPUReason {
SYNC_GPU_NONE,
SYNC_GPU_OTHER,
SYNC_GPU_WRAPAROUND,
SYNC_GPU_EFB_POKE,
SYNC_GPU_PERFQUERY,
SYNC_GPU_SWAP,
SYNC_GPU_AUX_SPACE,
};
// In g_use_deterministic_gpu_thread mode, waits for the GPU to be done with pending work.
void SyncGPU(SyncGPUReason reason, bool may_move_read_ptr = true);
void PushFifoAuxBuffer(void* ptr, size_t size);
void* PopFifoAuxBuffer(size_t size);
void RunGpu();
void RunGpuLoop();
void ExitGpuLoop();
void EmulatorState(bool running);
BIG FIFO Commit PART 1! Sometimes you need to write everything from 0, so 10 days later Ive rewrited some parts of the FIFO in Dual Core mode. Is pending use the same code for SC mode. - Improved the GP Register Status: now this is all the time from the fifo loop. - Improved the Interrupts manage: 1) Removed All UpdateInturrupts from CommandProcessor Writes and Read. 2) now the CP interrupts are schedule from the video thread and the fifo loop waiting until this happens 3) considering Inmediate mode for the CP interrupts 3) Implemented Interrupt CP Cache State 4) Implemented only Overflow interrupt in GatherPipeCheck because this need to be detected quickly. - Implemented Overflow handling like a real HW, when Hiwatermark interrupt happens this write ClearRegister with True en HI and False in LO (FifoIntReset) after that a Control Register is writed and the FIFO is processed to LO Watermark. - Removed all ugly code from LO and HI watermark manage - Removed all ugly code from BP manage - Change >= by == in the BP clauses - Removed speed hack (1024 chunk) for better GP Status Control. - Commented GXSetGPFifo very soon hack - Commented FackWatchDog hack - Commented FIFO_RW_DISTANCE = WritePointer hack This is the beginning and the base for the future., If this broke your favorite game my apologize, only report this and will try solve it. If you have a Overflown don't worry, I've implemented the real solution code using the Overflow Interruption only need continue working for a perfect protection. Why I did it? Because is preferable a accurate and clean fifo instead hack y fifo for improve that. Thanks to DONKO for you awesome Video Plug in and skid for the chatting. PD: I have 7-10 fps more in the star fox video. bye :P git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@6554 8ced0084-cf51-0410-be5f-012b33b47a6e
2010-12-11 05:42:55 -07:00
bool AtBreakpoint();
void ResetVideoBuffer();
void Fifo_SetRendering(bool bEnabled);
// Implemented by the Video Backend
void VideoFifo_CheckAsyncRequest();