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);