DMA: Implement interrupts

src/pse/dma.cpp

@@ -4,15 +4,17 @@
 #include "cdrom.h"
 #include "common/state_wrapper.h"
 #include "gpu.h"
+#include "interrupt_controller.h"
 Log_SetChannel(DMA);
 
 DMA::DMA() = default;
 
 DMA::~DMA() = default;
 
-bool DMA::Initialize(Bus* bus, GPU* gpu, CDROM* cdrom)
+bool DMA::Initialize(Bus* bus, InterruptController* interrupt_controller, GPU* gpu, CDROM* cdrom)
 {
   m_bus = bus;
+  m_interrupt_controller = interrupt_controller;
   m_gpu = gpu;
   m_cdrom = cdrom;
   return true;
@@ -22,7 +24,7 @@ void DMA::Reset()
 {
   m_state = {};
   m_DPCR.bits = 0x07654321;
-  m_DCIR = 0;
+  m_DICR.bits = 0;
 }
 
 bool DMA::DoState(StateWrapper& sw)
@@ -37,7 +39,7 @@ bool DMA::DoState(StateWrapper& sw)
   }
 
   sw.Do(&m_DPCR.bits);
-  sw.Do(&m_DCIR);
+  sw.Do(&m_DICR.bits);
   return !sw.HasError();
 }
 
@@ -63,7 +65,7 @@ u32 DMA::ReadRegister(u32 offset)
     if (offset == 0x70)
       return m_DPCR.bits;
     else if (offset == 0x74)
-      return m_DCIR;
+      return m_DICR.bits;
   }
 
   Log_ErrorPrintf("Unhandled register read: %02X", offset);
@@ -119,8 +121,10 @@ void DMA::WriteRegister(u32 offset, u32 value)
 
       case 0x74:
       {
-        m_DCIR = (m_DCIR & ~DCIR_WRITE_MASK) | (value & DCIR_WRITE_MASK);
+        Log_DebugPrintf("DCIR <- 0x%08X", value);
-        Log_DebugPrintf("DCIR <- 0x%08X", m_DCIR);
+        m_DICR.bits = (m_DICR.bits & ~DICR_WRITE_MASK) | (value & DICR_WRITE_MASK);
+        m_DICR.bits = (m_DICR.bits & ~DICR_RESET_MASK) & (value ^ DICR_RESET_MASK);
+        m_DICR.UpdateMasterFlag();
         return;
       }
 
@@ -293,6 +297,17 @@ void DMA::RunDMA(Channel channel)
 
   // start/busy bit is cleared on end of transfer
   cs.channel_control.enable_busy = false;
+  if (m_DICR.IsIRQEnabled(channel))
+  {
+    Log_DebugPrintf("Set DMA interrupt for channel %u", static_cast<u32>(channel));
+    m_DICR.SetIRQFlag(channel);
+    m_DICR.UpdateMasterFlag();
+    if (m_DICR.master_flag)
+    {
+      Log_DebugPrintf("Firing DMA interrupt");
+      m_interrupt_controller->InterruptRequest(InterruptController::IRQ::DMA);
+    }
+  }
 }
 
 u32 DMA::DMARead(Channel channel, PhysicalMemoryAddress dst_address, u32 remaining_words)

src/pse/dma.h

@@ -6,6 +6,7 @@
 class StateWrapper;
 
 class Bus;
+class InterruptController;
 class GPU;
 class CDROM;
 
@@ -31,7 +32,7 @@ public:
   DMA();
   ~DMA();
 
-  bool Initialize(Bus* bus, GPU* gpu, CDROM* cdrom);
+  bool Initialize(Bus* bus, InterruptController* interrupt_controller, GPU* gpu, CDROM* cdrom);
   void Reset();
   bool DoState(StateWrapper& sw);
 
@@ -63,6 +64,7 @@ private:
   void DMAWrite(Channel channel, u32 value, PhysicalMemoryAddress src_address, u32 remaining_words);
 
   Bus* m_bus = nullptr;
+  InterruptController* m_interrupt_controller = nullptr;
   GPU* m_gpu = nullptr;
   CDROM* m_cdrom = nullptr;
 
@@ -105,14 +107,32 @@ private:
     } channel_control;
 
     bool request = false;
+    bool irq = false;
   };
 
   std::array<ChannelState, NUM_CHANNELS> m_state = {};
 
-  struct DPCR
+  union DPCR
   {
     u32 bits;
 
+    BitField<u32, u8, 0, 3> MDECin_priority;
+    BitField<u32, bool, 3, 1> MDECin_master_enable;
+    BitField<u32, u8, 4, 3> MDECout_priority;
+    BitField<u32, bool, 7, 1> MDECout_master_enable;
+    BitField<u32, u8, 8, 3> GPU_priority;
+    BitField<u32, bool, 10, 1> GPU_master_enable;
+    BitField<u32, u8, 12, 3> CDROM_priority;
+    BitField<u32, bool, 15, 1> CDROM_master_enable;
+    BitField<u32, u8, 16, 3> SPU_priority;
+    BitField<u32, bool, 19, 1> SPU_master_enable;
+    BitField<u32, u8, 20, 3> PIO_priority;
+    BitField<u32, bool, 23, 1> PIO_master_enable;
+    BitField<u32, u8, 24, 3> OTC_priority;
+    BitField<u32, bool, 27, 1> OTC_master_enable;
+    BitField<u32, u8, 28, 3> priority_offset;
+    BitField<u32, bool, 31, 1> unused;
+
     u8 GetPriority(Channel channel) const { return ((bits >> (static_cast<u8>(channel) * 4)) & u32(3)); }
     bool GetMasterEnable(Channel channel) const
     {
@@ -120,6 +140,46 @@ private:
     }
   } m_DPCR;
 
-  static constexpr u32 DCIR_WRITE_MASK = 0b11111111'11111111'10000000'00111111;
+  static constexpr u32 DICR_WRITE_MASK = 0b00000000'11111111'10000000'00111111;
-  u32 m_DCIR = 0;
+  static constexpr u32 DICR_RESET_MASK = 0b01111111'00000000'00000000'00000000;
+  union DICR
+  {
+    u32 bits;
+
+    BitField<u32, bool, 15, 1> force_irq;
+    BitField<u32, bool, 16, 1> MDECin_irq_enable;
+    BitField<u32, bool, 17, 1> MDECout_irq_enable;
+    BitField<u32, bool, 18, 1> GPU_irq_enable;
+    BitField<u32, bool, 19, 1> CDROM_irq_enable;
+    BitField<u32, bool, 20, 1> SPU_irq_enable;
+    BitField<u32, bool, 21, 1> PIO_irq_enable;
+    BitField<u32, bool, 22, 1> OTC_irq_enable;
+    BitField<u32, bool, 23, 1> master_enable;
+    BitField<u32, bool, 24, 1> MDECin_irq_flag;
+    BitField<u32, bool, 25, 1> MDECout_irq_flag;
+    BitField<u32, bool, 26, 1> GPU_irq_flag;
+    BitField<u32, bool, 27, 1> CDROM_irq_flag;
+    BitField<u32, bool, 28, 1> SPU_irq_flag;
+    BitField<u32, bool, 29, 1> PIO_irq_flag;
+    BitField<u32, bool, 30, 1> OTC_irq_flag;
+    BitField<u32, bool, 31, 1> master_flag;
+
+    bool IsIRQEnabled(Channel channel) const
+    {
+      return ConvertToBoolUnchecked((bits >> (static_cast<u8>(channel) + 16)) & u32(1));
+    }
+
+    bool GetIRQFlag(Channel channel) const
+    {
+      return ConvertToBoolUnchecked((bits >> (static_cast<u8>(channel) + 24)) & u32(1));
+    }
+
+    void SetIRQFlag(Channel channel) { bits |= (u32(1) << (static_cast<u8>(channel) + 24)); }
+    void ClearIRQFlag(Channel channel) { bits &= ~(u32(1) << (static_cast<u8>(channel) + 24)); }
+
+    void UpdateMasterFlag()
+    {
+      master_flag = master_enable && ((((bits >> 16) & u32(0b1111111)) & ((bits >> 24) & u32(0b1111111))) != 0);
+    }
+  } m_DICR = {};
 };

src/pse/system.cpp

@@ -39,7 +39,7 @@ bool System::Initialize()
     return false;
   }
 
-  if (!m_dma->Initialize(m_bus.get(), m_gpu.get(), m_cdrom.get()))
+  if (!m_dma->Initialize(m_bus.get(), m_interrupt_controller.get(), m_gpu.get(), m_cdrom.get()))
     return false;
 
   if (!m_interrupt_controller->Initialize(m_cpu.get()))