N64 Audio integration

src/core/Audio.cpp

@@ -0,0 +1,83 @@
+#include <Audio.hpp>
+#include <SDL2/SDL.h>
+#include <util.hpp>
+
+namespace natsukashii::core {
+#define AUDIO_SAMPLE_RATE 48000
+#define SYSTEM_SAMPLE_FORMAT AUDIO_F32SYS
+#define SYSTEM_SAMPLE_SIZE 4
+#define BYTES_PER_HALF_SECOND ((AUDIO_SAMPLE_RATE / 2) * SYSTEM_SAMPLE_SIZE)
+
+static SDL_AudioStream* audioStream = nullptr;
+SDL_mutex* audioStreamMutex;
+SDL_AudioSpec audioSpec;
+SDL_AudioSpec request;
+SDL_AudioDeviceID audioDev;
+
+#define LockAudioMutex() SDL_LockMutex(audioStreamMutex)
+#define UnlockAudioMutex() SDL_UnlockMutex(audioStreamMutex)
+
+void audioCallback(void* userdata, Uint8* stream, int length) {
+  int gotten = 0;
+  LockAudioMutex();
+  int available = SDL_AudioStreamAvailable(audioStream);
+
+  if (available > 0) {
+    gotten = SDL_AudioStreamGet(audioStream, stream, length);
+  }
+  UnlockAudioMutex();
+
+  int gotten_samples = (int)(gotten / sizeof(float));
+  auto* out = (float*)stream;
+  out += gotten_samples;
+
+  for (int i = gotten_samples; i < length / sizeof(float); i++) {
+    float sample = 0;
+    *out++ = sample;
+  }
+}
+
+void InitAudio() {
+  AdjustSampleRate(AUDIO_SAMPLE_RATE);
+  memset(&request, 0, sizeof(request));
+
+  request.freq = AUDIO_SAMPLE_RATE;
+  request.format = SYSTEM_SAMPLE_FORMAT;
+  request.channels = 2;
+  request.samples = 1024;
+  request.callback = audioCallback;
+  request.userdata = nullptr;
+
+  audioDev = SDL_OpenAudioDevice(nullptr, 0, &request, &audioSpec, 0);
+
+  if(!audioDev) {
+    util::panic("Failed to initialize SDL Audio: {}", SDL_GetError());
+  }
+
+  SDL_PauseAudioDevice(audioDev, false);
+
+  audioStreamMutex = SDL_CreateMutex();
+
+  if(!audioStreamMutex) {
+    util::panic("Unable to initialize audio mutex: {}", SDL_GetError());
+  }
+}
+
+void PushSample(s16 left, s16 right) {
+  s16 samples[2]{ left, right };
+
+  int availableBytes = SDL_AudioStreamAvailable(audioStream);
+  if(availableBytes < BYTES_PER_HALF_SECOND) {
+    SDL_AudioStreamPut(audioStream, samples, 2 * sizeof(16));
+  }
+}
+
+void AdjustSampleRate(int sampleRate) {
+  LockAudioMutex();
+  if(audioStream) SDL_FreeAudioStream(audioStream);
+
+  audioStream = SDL_NewAudioStream(AUDIO_S16SYS, 2, sampleRate, SYSTEM_SAMPLE_FORMAT, 2, AUDIO_SAMPLE_RATE);
+  UnlockAudioMutex();
+}
+
+}

src/core/Audio.hpp

@@ -0,0 +1,8 @@
+#pragma once
+#include <common.hpp>
+
+namespace natsukashii::core {
+void PushSample(s16, s16);
+void InitAudio();
+void AdjustSampleRate(int);
+}

src/core/CMakeLists.txt

@@ -10,6 +10,6 @@ add_library(cores
   Scheduler.cpp
   Scheduler.hpp
   common.hpp
-  util.hpp)
+  util.hpp Audio.hpp Audio.cpp)
 target_include_directories(cores PUBLIC . ../../external)
 target_link_libraries(cores PUBLIC gb n64)

src/core/n64/core/MMIO.hpp

@@ -1,6 +1,7 @@
 #pragma once
 #include <n64/core/mmio/VI.hpp>
 #include <n64/core/mmio/MI.hpp>
+#include <n64/core/mmio/AI.hpp>
 #include <n64/core/RSP.hpp>
 #include <n64/core/RDP.hpp>
 
@@ -12,6 +13,7 @@ struct MMIO {
   MMIO() = default;
   VI vi;
   MI mi;
+  AI ai;
   RSP rsp;
   RDP rdp;
 

src/core/n64/core/RDP.cpp

@@ -92,7 +92,7 @@ void RDP::RunCommand(MI& mi, Registers& regs, RSP& rsp) {
 
       if (cmd == 0x29) {
         OnFullSync();
-        InterruptRaise(mi, regs, InterruptType::DP);
+        InterruptRaise(mi, regs, Interrupt::DP);
       }
 
       buf_index += cmd_len;

src/core/n64/core/RSP.cpp

@@ -78,8 +78,8 @@ void RSP::Write(Mem& mem, Registers& regs, u32 addr, u32 value) {
       write.raw = value;
       CLEAR_SET(spStatus.halt, write.clearHalt, write.setHalt);
       CLEAR_SET(spStatus.broke, write.clearBroke, false);
-      if(write.clearIntr) InterruptLower(mi, regs, InterruptType::SP);
-      if(write.setIntr) InterruptRaise(mi, regs, InterruptType::SP);
+      if(write.clearIntr) InterruptLower(mi, regs, Interrupt::SP);
+      if(write.setIntr) InterruptRaise(mi, regs, Interrupt::SP);
       CLEAR_SET(spStatus.singleStep, write.clearSstep, write.setSstep);
       CLEAR_SET(spStatus.interruptOnBreak, write.clearIntrOnBreak, write.setIntrOnBreak);
       CLEAR_SET(spStatus.signal0Set, write.clearSignal0, write.setSignal0);

src/core/n64/core/mmio/AI.cpp

@@ -2,6 +2,7 @@
 #include <util.hpp>
 #include <n64/core/Mem.hpp>
 #include <n64/core/cpu/Registers.hpp>
+#include <Audio.hpp>
 
 namespace natsukashii::n64::core {
 auto AI::Read(u32 addr) const -> u32 {
@@ -23,6 +24,8 @@ auto AI::Read(u32 addr) const -> u32 {
 
 #define max(x, y) ((x) > (y) ? (x) : (y))
 
+using namespace natsukashii::core;
+
 void AI::Write(Mem& mem, Registers& regs, u32 addr, u32 val) {
   switch(addr) {
     case 0x04500000:

src/core/n64/core/mmio/MI.cpp

@@ -18,7 +18,7 @@ auto MI::Read(u32 paddr) const -> u32 {
     case 0x4: return MI_VERSION_REG;
     case 0x8: return miIntr.raw & 0x3F;
     case 0xC: return miIntrMask.raw & 0x3F;
-    default: util::panic("Unhandled MI[%08X] read\n", paddr);
+    default: util::panic("Unhandled MI[{:08X}] read\n", paddr);
   }
   return 0;
 }
@@ -45,7 +45,7 @@ void MI::Write(Registers& regs, u32 paddr, u32 val) {
       }
 
       if (val & (1 << 11)) {
-        InterruptLower(*this, regs, InterruptType::DP);
+        InterruptLower(*this, regs, Interrupt::DP);
       }
 
       if (val & (1 << 12)) {
@@ -74,7 +74,7 @@ void MI::Write(Registers& regs, u32 paddr, u32 val) {
       UpdateInterrupt(*this, regs);
       break;
     default:
-      util::panic("Unhandled MI[%08X] write (%08X)\n", val, paddr);
+      util::panic("Unhandled MI[{:08X}] write ({:08X})\n", val, paddr);
   }
 }
 }

src/core/n64/core/mmio/VI.cpp

@@ -60,7 +60,7 @@ void VI::Write(MI& mi, Registers& regs, u32 paddr, u32 val) {
       intr = val & 0x3FF;
     } break;
     case 0x04400010:
-      InterruptLower(mi, regs, InterruptType::VI);
+      InterruptLower(mi, regs, Interrupt::VI);
       break;
     case 0x04400014: burst.raw = val; break;
     case 0x04400018: {