Implemented proper timing for the sample counter in the AudioInterface, removing the previous hack.

Cleaned up some of the audio streaming code.

Source/Core/Core/Src/HW/AudioInterface.cpp

@@ -145,6 +145,8 @@ static void GenerateAudioInterrupt();
 static void UpdateInterrupts();
 static void IncreaseSampleCount(const u32 _uAmount);
 void ReadStreamBlock(s16* _pPCM);
+u64 GetAIPeriod();
+int et_AI;
 
 void Init()
 {
@@ -159,6 +161,8 @@ void Init()
 
 	g_AISSampleRate = 48000;
 	g_AIDSampleRate = 32000;
+
+	et_AI = CoreTiming::RegisterEvent("AICallback", Update);
 }
 
 void Shutdown()
@@ -178,11 +182,8 @@ void Read32(u32& _rReturnValue, const u32 _Address)
 		break;
 
 	case AI_SAMPLE_COUNTER:
+		Update(0, 0);
         _rReturnValue = m_SampleCounter;
-		// HACK - AI SRC init will do while (oldval == sample_counter) {}
-		// in order to pass this, we need to increment the counter whenever read
-		if (m_Control.PSTAT)
-			m_SampleCounter++;
 		break;
 
 	case AI_INTERRUPT_TIMING:
@@ -236,6 +237,9 @@ void Write32(const u32 _Value, const u32 _Address)
 
 				// Tell Drive Interface to start/stop streaming
 				DVDInterface::g_bStream = tmpAICtrl.PSTAT;
+
+				CoreTiming::RemoveEvent(et_AI);
+				CoreTiming::ScheduleEvent(((int)GetAIPeriod() / 2), et_AI);
             }
 
             // AI Interrupt
@@ -271,6 +275,8 @@ void Write32(const u32 _Value, const u32 _Address)
 
 	case AI_INTERRUPT_TIMING:		
 		m_InterruptTiming = _Value;
+		CoreTiming::RemoveEvent(et_AI);
+		CoreTiming::ScheduleEvent(((int)GetAIPeriod() / 2), et_AI);
 		DEBUG_LOG(AUDIO_INTERFACE, "Set interrupt: %08x samples", m_InterruptTiming);
 		break;
 
@@ -448,7 +454,7 @@ unsigned int GetAIDSampleRate()
 	return g_AIDSampleRate;
 }
 
-void Update()
+void Update(u64 userdata, int cyclesLate)
 {
     if (m_Control.PSTAT)
     {
@@ -458,8 +464,17 @@ void Update()
             const u32 Samples = static_cast<u32>(Diff / g_CPUCyclesPerSample);
             g_LastCPUTime += Samples * g_CPUCyclesPerSample;
 			IncreaseSampleCount(Samples);
-        } 
+        }
+		CoreTiming::ScheduleEvent(((int)GetAIPeriod() / 2) - cyclesLate, et_AI);
     }
 }
 
+u64 GetAIPeriod()
+{
+	u64 period = g_CPUCyclesPerSample * m_InterruptTiming;
+	if (period == 0)
+		period = 32000 * g_CPUCyclesPerSample;
+	return period;
+}
+
 } // end of namespace AudioInterface

Source/Core/Core/Src/HW/AudioInterface.h

@@ -31,7 +31,7 @@ void Init();
 void Shutdown();	
 void DoState(PointerWrap &p);
 
-void Update();
+void Update(u64 userdata, int cyclesLate);
 
 // Called by DSP emulator
 void Callback_GetSampleRate(unsigned int &_AISampleRate, unsigned int &_DACSampleRate);

Source/Core/Core/Src/HW/DSP.cpp

@@ -47,6 +47,7 @@
 #include "../PowerPC/PowerPC.h"
 #include "../ConfigManager.h"
 #include "../DSPEmulator.h"
+#include "SystemTimers.h"
 
 namespace DSP
 {
@@ -152,7 +153,7 @@ struct AudioDMA
 		SourceAddress = 0;
 		ReadAddress = 0;
 		AudioDMAControl.Hex = 0;
-		BlocksLeft = 0;
+		BlocksLeft = 1;
 	}
 };
 
@@ -355,7 +356,7 @@ void Read16(u16& _uReturnValue, const u32 _iAddress)
 
 		// AI
 	case AUDIO_DMA_BLOCKS_LEFT:
-		_uReturnValue = g_audioDMA.BlocksLeft > 0 ? g_audioDMA.BlocksLeft - 1 : 0; // AUDIO_DMA_BLOCKS_LEFT is zero based
+		_uReturnValue = g_audioDMA.BlocksLeft;
 		break;
 
 	case AUDIO_DMA_START_LO:
@@ -665,7 +666,7 @@ void UpdateDSPSlice(int cycles) {
 // This happens at 4 khz, since 32 bytes at 4khz = 4 bytes at 32 khz (16bit stereo pcm)
 void UpdateAudioDMA()
 {
-	if (g_audioDMA.AudioDMAControl.Enable && g_audioDMA.BlocksLeft)
+	if (g_audioDMA.AudioDMAControl.Enable && g_audioDMA.BlocksLeft > -1)
 	{
 		// Read audio at g_audioDMA.ReadAddress in RAM and push onto an
 		// external audio fifo in the emulator, to be mixed with the disc
@@ -675,7 +676,7 @@ void UpdateAudioDMA()
 		g_audioDMA.BlocksLeft--;
 		g_audioDMA.ReadAddress += 32;
 
-		if (g_audioDMA.BlocksLeft == 0)
+		if (g_audioDMA.BlocksLeft == -1)
 		{
 			dsp_emulator->DSP_SendAIBuffer(g_audioDMA.SourceAddress, 8*g_audioDMA.AudioDMAControl.NumBlocks);
 			GenerateDSPInterrupt(DSP::INT_AID);
@@ -687,7 +688,7 @@ void UpdateAudioDMA()
 	{
 		// Send silence. Yeah, it's a bit of a waste to sample rate convert
 		// silence.  or hm. Maybe we shouldn't do this :)
-		//dsp_emulator->DSP_SendAIBuffer(0, AudioInterface::GetAIDSampleRate());
+		dsp_emulator->DSP_SendAIBuffer(0, AudioInterface::GetAIDSampleRate());
 	}
 }
 

Source/Core/Core/Src/HW/SystemTimers.cpp

@@ -110,7 +110,6 @@ enum
 int et_Dec;
 int et_VI;
 int et_SI;
-int et_AI;
 int et_CP;
 int et_AudioDMA;
 int et_DSP;
@@ -120,9 +119,6 @@ int et_PatchEngine;	// PatchEngine updates every 1/60th of a second by default
 // These are badly educated guesses
 // Feel free to experiment. Set these in Init below.
 int
-	// This one should simply be determined by the increasing counter in AI.
-	AI_PERIOD,
-
 	// These shouldn't be period controlled either, most likely.
 	DSP_PERIOD,
 
@@ -148,12 +144,6 @@ u32 ConvertMillisecondsToTicks(u32 _Milliseconds)
 	return GetTicksPerSecond() / 1000 * _Milliseconds;
 }
 
-void AICallback(u64 userdata, int cyclesLate)
-{
-	AudioInterface::Update();
-	CoreTiming::ScheduleEvent(AI_PERIOD - cyclesLate, et_AI);
-}
-
 // DSP/CPU timeslicing.
 void DSPCallback(u64 userdata, int cyclesLate)
 {
@@ -277,9 +267,6 @@ void Init()
 	if (DSP::GetDSPEmulator()->IsLLE())
 		DSP_PERIOD = 12000; // TO BE TWEAKED
 
-	// This is the biggest question mark.
-	AI_PERIOD = GetTicksPerSecond() / 80;
-
 	// System internal sample rate is fixed at 32KHz * 4 (16bit Stereo) / 32 bytes DMA
 	AUDIO_DMA_PERIOD = CPU_CORE_CLOCK / (AudioInterface::GetAIDSampleRate() * 4 / 32);
 
@@ -295,7 +282,6 @@ void Init()
 	CoreTiming::SetFakeDecStartTicks(CoreTiming::GetTicks());
 
 	et_Dec = CoreTiming::RegisterEvent("DecCallback", DecrementerCallback);
-	et_AI = CoreTiming::RegisterEvent("AICallback", AICallback);
 	et_VI = CoreTiming::RegisterEvent("VICallback", VICallback);
 	et_SI = CoreTiming::RegisterEvent("SICallback", SICallback);
 	if (SConfig::GetInstance().m_LocalCoreStartupParameter.bSyncGPU)
@@ -305,7 +291,6 @@ void Init()
 	et_IPC_HLE = CoreTiming::RegisterEvent("IPC_HLE_UpdateCallback", IPC_HLE_UpdateCallback);
 	et_PatchEngine = CoreTiming::RegisterEvent("PatchEngine", PatchEngineCallback);
 
-	CoreTiming::ScheduleEvent(AI_PERIOD, et_AI);
 	CoreTiming::ScheduleEvent(VideoInterface::GetTicksPerLine(), et_VI);
 	CoreTiming::ScheduleEvent(DSP_PERIOD, et_DSP);
 	CoreTiming::ScheduleEvent(VideoInterface::GetTicksPerFrame(), et_SI);