Fifo: Fix SyncGPU.

CBoot::BootUp() did call CoreTiming::Advance which itself blocks on the GPU,
but the GPU thread wasn't started already. This commit moves the SyncGPU
initialization into the Fifo.cpp file and call it after BootUp().

Source/Core/Core/Core.cpp

@@ -498,6 +498,9 @@ void EmuThread()
 
 	CBoot::BootUp();
 
+	// This adds the SyncGPU handler to CoreTiming, so now CoreTiming::Advance might block.
+	Fifo::Prepare();
+
 	// Thread is no longer acting as CPU Thread
 	UndeclareAsCPUThread();
 

Source/Core/Core/CoreTiming.cpp

@@ -446,7 +446,7 @@ void Idle()
 		//the VI will be desynchronized. So, We are waiting until the FIFO finish and
 		//while we process only the events required by the FIFO.
 		ProcessFifoWaitEvents();
-		Fifo::Update(0);
+		Fifo::FlushGpu();
 	}
 
 	idledCycles += DowncountToCycles(PowerPC::ppcState.downcount);

Source/Core/Core/HW/SystemTimers.cpp

@@ -66,7 +66,6 @@ namespace SystemTimers
 
 static int et_Dec;
 static int et_VI;
-static int et_CP;
 static int et_AudioDMA;
 static int et_DSP;
 static int et_IPC_HLE;
@@ -74,7 +73,6 @@ static int et_PatchEngine; // PatchEngine updates every 1/60th of a second by de
 static int et_Throttle;
 
 static u32 s_cpu_core_clock = 486000000u;             // 486 mhz (its not 485, stop bugging me!)
-static u64 s_last_sync_gpu_tick;
 
 // These two are badly educated guesses.
 // Feel free to experiment. Set them in Init below.
@@ -123,16 +121,6 @@ static void VICallback(u64 userdata, int cyclesLate)
 	CoreTiming::ScheduleEvent(VideoInterface::GetTicksPerHalfLine() - cyclesLate, et_VI);
 }
 
-static void CPCallback(u64 userdata, int cyclesLate)
-{
-	u64 now = CoreTiming::GetTicks();
-	int next = Fifo::Update((int)(now - s_last_sync_gpu_tick));
-	s_last_sync_gpu_tick = now;
-
-	if (next > 0)
-		CoreTiming::ScheduleEvent(next, et_CP);
-}
-
 static void DecrementerCallback(u64 userdata, int cyclesLate)
 {
 	PowerPC::ppcState.spr[SPR_DEC] = 0xFFFFFFFF;
@@ -238,8 +226,6 @@ void Init()
 
 	et_Dec = CoreTiming::RegisterEvent("DecCallback", DecrementerCallback);
 	et_VI = CoreTiming::RegisterEvent("VICallback", VICallback);
-	if (SConfig::GetInstance().bCPUThread && SConfig::GetInstance().bSyncGPU)
-		et_CP = CoreTiming::RegisterEvent("CPCallback", CPCallback);
 	et_DSP = CoreTiming::RegisterEvent("DSPCallback", DSPCallback);
 	et_AudioDMA = CoreTiming::RegisterEvent("AudioDMACallback", AudioDMACallback);
 	et_IPC_HLE = CoreTiming::RegisterEvent("IPC_HLE_UpdateCallback", IPC_HLE_UpdateCallback);
@@ -250,9 +236,6 @@ void Init()
 	CoreTiming::ScheduleEvent(0, et_DSP);
 	CoreTiming::ScheduleEvent(s_audio_dma_period, et_AudioDMA);
 	CoreTiming::ScheduleEvent(0, et_Throttle, Common::Timer::GetTimeMs());
-	if (SConfig::GetInstance().bCPUThread && SConfig::GetInstance().bSyncGPU)
-		CoreTiming::ScheduleEvent(0, et_CP);
-	s_last_sync_gpu_tick = CoreTiming::GetTicks();
 
 	CoreTiming::ScheduleEvent(VideoInterface::GetTicksPerField(), et_PatchEngine);
 

Source/Core/VideoCommon/Fifo.cpp

@@ -15,6 +15,7 @@
 #include "Common/MsgHandler.h"
 
 #include "Core/ConfigManager.h"
+#include "Core/CoreTiming.h"
 #include "Core/NetPlayProto.h"
 #include "Core/HW/Memmap.h"
 
@@ -45,6 +46,9 @@ static u8* s_fifo_aux_read_ptr;
 
 bool g_use_deterministic_gpu_thread;
 
+static u64 s_last_sync_gpu_tick;
+static int s_et_syncGPU;
+
 // STATE_TO_SAVE
 static u8* s_video_buffer;
 static u8* s_video_buffer_read_ptr;
@@ -79,6 +83,7 @@ void DoState(PointerWrap &p)
 		s_video_buffer_seen_ptr = s_video_buffer_pp_read_ptr = s_video_buffer_read_ptr;
 	}
 	p.Do(g_bSkipCurrentFrame);
+	p.Do(s_last_sync_gpu_tick);
 }
 
 void PauseAndLock(bool doLock, bool unpauseOnUnlock)
@@ -492,16 +497,10 @@ void UpdateWantDeterminism(bool want)
 	}
 }
 
-int Update(int ticks)
+static int Update(int ticks)
 {
 	const SConfig& param = SConfig::GetInstance();
 
-	if (ticks == 0)
-	{
-		FlushGpu();
-		return param.iSyncGpuMaxDistance;
-	}
-
 	// GPU is sleeping, so no need for synchronization
 	if (s_gpu_mainloop.IsDone() || g_use_deterministic_gpu_thread)
 	{
@@ -529,4 +528,24 @@ int Update(int ticks)
 	return param.iSyncGpuMaxDistance - s_sync_ticks.load();
 }
 
+static void SyncGPUCallback(u64 userdata, int cyclesLate)
+{
+	u64 now = CoreTiming::GetTicks();
+	int next = Fifo::Update((int)(now - s_last_sync_gpu_tick));
+	s_last_sync_gpu_tick = now;
+
+	if (next > 0)
+		CoreTiming::ScheduleEvent(next, s_et_syncGPU);
+}
+
+void Prepare()
+{
+	if (SConfig::GetInstance().bCPUThread && SConfig::GetInstance().bSyncGPU)
+	{
+		s_et_syncGPU = CoreTiming::RegisterEvent("SyncGPUCallback", SyncGPUCallback);
+		CoreTiming::ScheduleEvent(0, s_et_syncGPU);
+		s_last_sync_gpu_tick = CoreTiming::GetTicks();
+	}
+}
+
 }

Source/Core/VideoCommon/Fifo.h

@@ -22,6 +22,7 @@ extern std::atomic<u8*> g_video_buffer_write_ptr_xthread;
 
 void Init();
 void Shutdown();
+void Prepare(); // Must be called from the CPU thread.
 void DoState(PointerWrap &f);
 void PauseAndLock(bool doLock, bool unpauseOnUnlock);
 void UpdateWantDeterminism(bool want);
@@ -52,6 +53,5 @@ void EmulatorState(bool running);
 bool AtBreakpoint();
 void ResetVideoBuffer();
 void SetRendering(bool bEnabled);
-int Update(int ticks);
 
 };