Periodically signal hsync instead of having it always on.

jpd002 · Oct 13, 2023 · 1eec610 · 1eec610
1 parent ddf2966
commit 1eec610
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Showing 4 changed files with 38 additions and 12 deletions.
diff --git a/Source/PS2VM.cpp b/Source/PS2VM.cpp
@@ -183,19 +183,23 @@ void CPS2VM::SetEeFrequencyScale(uint32 numerator, uint32 denominator)
 
 void CPS2VM::ReloadFrameRateLimit()
 {
-	uint32 frameRate = 60;
+	uint32 hRefreshRate = PS2::GS_NTSC_HSYNC_FREQ;
+	uint32 vRefreshRate = 60;
 	if(m_ee && m_ee->m_gs)
 	{
-		frameRate = m_ee->m_gs->GetCrtFrameRate();
+		hRefreshRate = m_ee->m_gs->GetCrtHSyncFrequency();
+		vRefreshRate = m_ee->m_gs->GetCrtFrameRate();
 	}
 	bool limitFrameRate = CAppConfig::GetInstance().GetPreferenceBoolean(PREF_PS2_LIMIT_FRAMERATE);
-	m_frameLimiter.SetFrameRate(limitFrameRate ? frameRate : 0);
+	m_frameLimiter.SetFrameRate(limitFrameRate ? vRefreshRate : 0);
 
 	//At 1x scale, IOP runs 8 times slower than EE
 	uint32 eeFreqScaled = PS2::EE_CLOCK_FREQ * m_eeFreqScaleNumerator / m_eeFreqScaleDenominator;
 	m_iopTickStep = (m_eeTickStep / 8) * m_eeFreqScaleDenominator / m_eeFreqScaleNumerator;
 
-	uint32 frameTicks = eeFreqScaled / frameRate;
+	m_hblankTicksTotal = eeFreqScaled / hRefreshRate;
+
+	uint32 frameTicks = eeFreqScaled / vRefreshRate;
 	m_onScreenTicksTotal = frameTicks * 9 / 10;
 	m_vblankTicksTotal = frameTicks / 10;
 
@@ -481,6 +485,7 @@ void CPS2VM::ResetVM()
 
 	SetEeFrequencyScale(1, 1);
 
+	m_hblankTicks = m_hblankTicksTotal;
 	m_vblankTicks = m_onScreenTicksTotal;
 	m_spuUpdateTicks = m_spuUpdateTicksTotal;
 	m_inVblank = false;
@@ -715,6 +720,7 @@ void CPS2VM::UpdateEe()
 		m_eeExecutionTicks -= executed;
 		m_spuUpdateTicks -= (static_cast<int64>(executed) << SPU_UPDATE_TICKS_PRECISION);
 		m_ee->CountTicks(executed);
+		m_hblankTicks -= executed;
 		m_vblankTicks -= executed;
 
 #ifdef DEBUGGER_INCLUDED
@@ -897,6 +903,15 @@ void CPS2VM::EmuThread()
 			}
 
 			{
+				if(m_hblankTicks <= 0)
+				{
+					if(m_ee->m_gs)
+					{
+						m_ee->m_gs->SetHBlank();
+						m_hblankTicks += m_hblankTicksTotal;
+					}
+				}
+
 				//Check vblank stuff
 				if(m_vblankTicks <= 0)
 				{

diff --git a/Source/PS2VM.h b/Source/PS2VM.h
@@ -158,8 +158,10 @@ class CPS2VM : public CVirtualMachine
 	uint32 m_eeFreqScaleDenominator = 1;
 	uint32 m_eeRamSize = PS2::EE_BASE_RAM_SIZE;
 	uint32 m_iopRamSize = PS2::IOP_BASE_RAM_SIZE;
+	uint32 m_hblankTicksTotal = 0;
 	uint32 m_onScreenTicksTotal = 0;
 	uint32 m_vblankTicksTotal = 0;
+	int m_hblankTicks = 0;
 	int m_vblankTicks = 0;
 	bool m_inVblank = false;
 	int64 m_spuUpdateTicks = 0;

diff --git a/Source/gs/GSHandler.cpp b/Source/gs/GSHandler.cpp
@@ -375,6 +375,13 @@ void CGSHandler::SetDrawEnabled(bool drawEnabled)
 	m_drawEnabled = drawEnabled;
 }
 
+void CGSHandler::SetHBlank()
+{
+	std::lock_guard registerMutexLock(m_registerMutex);
+	m_nCSR |= CSR_HSYNC_INT;
+	NotifyEvent(CSR_HSYNC_INT);
+}
+
 void CGSHandler::SetVBlank()
 {
 	{
@@ -412,14 +419,11 @@ uint32 CGSHandler::ReadPrivRegister(uint32 nAddress)
 	{
 	case GS_CSR:
 	case GS_CSR_ALT:
-		//Force CSR to have the H-Blank bit set.
-		{
-			std::lock_guard registerMutexLock(m_registerMutex);
-			m_nCSR |= CSR_HSYNC_INT;
-			NotifyEvent(CSR_HSYNC_INT);
-			R_REG(nAddress, nData, m_nCSR);
-		}
-		break;
+	{
+		std::lock_guard registerMutexLock(m_registerMutex);
+		R_REG(nAddress, nData, m_nCSR);
+	}
+	break;
 	case GS_IMR:
 		R_REG(nAddress, nData, m_nIMR);
 		break;
@@ -470,6 +474,10 @@ void CGSHandler::WritePrivRegister(uint32 nAddress, uint32 nData)
 			{
 				m_nCSR &= ~CSR_FINISH_EVENT;
 			}
+			if(nData & CSR_HSYNC_INT)
+			{
+				m_nCSR &= ~CSR_HSYNC_INT;
+			}
 			if(nData & CSR_VSYNC_INT)
 			{
 				m_nCSR &= ~CSR_VSYNC_INT;

diff --git a/Source/gs/GSHandler.h b/Source/gs/GSHandler.h
@@ -845,6 +845,7 @@ class CGSHandler
 	void SetLoggingEnabled(bool);
 	static std::string DisassembleWrite(uint8, uint64);
 
+	void SetHBlank();
 	void SetVBlank();
 	void ResetVBlank();