From 3c57322bd4ee1e81eecf9a6cb0bf1e1a7c9903bf Mon Sep 17 00:00:00 2001
From: Jean-Philip Desjardins <jean-philip.desjardins@polymtl.ca>
Date: Tue, 26 Sep 2023 18:27:55 -0400
Subject: [PATCH] Better throttling.

---
 Source/iop/Iop_SpuBase.cpp | 13 ++++---------
 Source/iop/Iop_SpuBase.h   |  2 +-
 2 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/Source/iop/Iop_SpuBase.cpp b/Source/iop/Iop_SpuBase.cpp
index bac2e7663..c5ec94647 100644
--- a/Source/iop/Iop_SpuBase.cpp
+++ b/Source/iop/Iop_SpuBase.cpp
@@ -325,6 +325,7 @@ uint16 CSpuBase::GetControl() const
 void CSpuBase::SetControl(uint16 value)
 {
 	m_ctrl = value;
+	m_transferTicks = 0;
 	if((m_ctrl & CONTROL_IRQ) == 0)
 	{
 		ClearIrqPending();
@@ -378,6 +379,7 @@ uint16 CSpuBase::GetTransferMode() const
 void CSpuBase::SetTransferMode(uint16 transferMode)
 {
 	m_transferMode = transferMode;
+	m_transferTicks = 0;
 }
 
 uint32 CSpuBase::GetTransferAddress() const
@@ -591,6 +593,7 @@ uint32 CSpuBase::ReceiveDma(uint8* buffer, uint32 blockSize, uint32 blockAmount,
 		uint32 availableBytes = SOUND_INPUT_DATA_SIZE - m_blockWritePtr;
 		uint32 availableBlocks = availableBytes / blockSize;
 		blockAmount = std::min({blockAmount, availableBlocks, blockTicks});
+		m_transferTicks -= (g_transferTicksPerBlock * blockAmount);
 
 		uint32 dstAddr = m_soundInputDataAddr + m_blockWritePtr;
 		memcpy(m_ram + dstAddr, buffer, blockAmount * blockSize);
@@ -811,15 +814,7 @@ void CSpuBase::Render(int16* samples, unsigned int sampleCount)
 		}
 	}
 	
-	switch(m_ctrl & CONTROL_DMA)
-	{
-	case CONTROL_DMA_STOP:
-		m_transferTicks = 0;
-		break;
-	default:
-		m_transferTicks += sampleCount;
-		break;
-	}
+	m_transferTicks += sampleCount;
 }
 
 uint32 CSpuBase::GetAdsrDelta(unsigned int index) const
diff --git a/Source/iop/Iop_SpuBase.h b/Source/iop/Iop_SpuBase.h
index 92fbe6fdc..de6fc6588 100644
--- a/Source/iop/Iop_SpuBase.h
+++ b/Source/iop/Iop_SpuBase.h
@@ -374,7 +374,7 @@ namespace Iop
 		static const uint32 g_linearIncreaseSweepDeltas[0x80];
 		static const uint32 g_linearDecreaseSweepDeltas[0x80];
 
-		static constexpr int32 g_transferTicksPerBlock = 16;
+		static constexpr int32 g_transferTicksPerBlock = 8;
 		
 		uint8* m_ram;
 		uint32 m_ramSize;