Core: Implement GBA Core using libmgba

Source/Core/Core/CMakeLists.txt

@@ -440,8 +440,8 @@ add_library(core
   PowerPC/Interpreter/Interpreter_Tables.cpp
   PowerPC/Interpreter/Interpreter.cpp
   PowerPC/Interpreter/Interpreter.h
-	PowerPC/JitCommon/DivUtils.cpp
-	PowerPC/JitCommon/DivUtils.h
+  PowerPC/JitCommon/DivUtils.cpp
+  PowerPC/JitCommon/DivUtils.h
   PowerPC/JitCommon/JitAsmCommon.cpp
   PowerPC/JitCommon/JitAsmCommon.h
   PowerPC/JitCommon/JitBase.cpp
@@ -621,6 +621,10 @@ if(ENABLE_VULKAN)
 endif()
 
 if(USE_MGBA)
+  target_sources(core PRIVATE
+    HW/GBACore.cpp
+    HW/GBACore.h
+  )
   target_link_libraries(core PUBLIC mGBA::mgba)
   target_compile_definitions(core PUBLIC -DHAS_LIBMGBA)
 endif()

Source/Core/Core/HW/GBACore.h

@@ -0,0 +1,129 @@
+// Copyright 2021 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <array>
+#include <condition_variable>
+#include <memory>
+#include <mutex>
+#include <queue>
+#include <string>
+#include <string_view>
+#include <thread>
+#include <vector>
+
+#define PYCPARSE  // Remove static functions from the header
+#include <mgba/core/interface.h>
+#undef PYCPARSE
+#include <mgba/core/core.h>
+#include <mgba/gba/interface.h>
+
+#include "Common/CommonTypes.h"
+
+class GBAHostInterface;
+class PointerWrap;
+
+namespace HW::GBA
+{
+class Core;
+struct SIODriver : GBASIODriver
+{
+  Core* core;
+};
+struct AVStream : mAVStream
+{
+  Core* core;
+};
+
+class Core final
+{
+public:
+  explicit Core(int device_number);
+  ~Core();
+
+  bool Start(u64 gc_ticks);
+  void Stop();
+  void Reset();
+  bool IsStarted() const;
+
+  void SetHost(std::weak_ptr<GBAHostInterface> host);
+  void SetForceDisconnect(bool force_disconnect);
+  void EReaderQueueCard(std::string_view card_path);
+
+  int GetDeviceNumber() const;
+  void GetVideoDimensions(u32* width, u32* height) const;
+  std::string GetGameTitle() const;
+
+  void SendJoybusCommand(u64 gc_ticks, int transfer_time, u8* buffer, u16 keys);
+  std::vector<u8> GetJoybusResponse();
+
+  void ImportState(std::string_view state_path);
+  void ExportState(std::string_view state_path);
+  void DoState(PointerWrap& p);
+
+  static bool GetRomInfo(const char* rom_path, std::array<u8, 20>& hash, std::string& title);
+  static std::string GetSavePath(std::string_view rom_path, int device_number);
+
+private:
+  void ThreadLoop();
+  void RunUntil(u64 gc_ticks);
+  void RunFor(u64 gc_ticks);
+  void Flush();
+
+  struct Command
+  {
+    u64 ticks;
+    int transfer_time;
+    bool sync_only;
+    std::array<u8, 6> buffer;
+    u16 keys;
+  };
+  void RunCommand(Command& command);
+
+  bool LoadBIOS(const char* bios_path);
+  bool LoadSave(const char* save_path);
+
+  void SetSIODriver();
+  void SetVideoBuffer();
+  void SetSampleRates();
+  void AddCallbacks();
+  void SetAVStream();
+  void SetupEvent();
+
+  const int m_device_number;
+
+  bool m_started = false;
+  std::string m_rom_path;
+  std::string m_save_path;
+  std::array<u8, 20> m_rom_hash{};
+  std::string m_game_title;
+
+  mCore* m_core{};
+  mTimingEvent m_event{};
+  bool m_waiting_for_event = false;
+  SIODriver m_sio_driver{};
+  AVStream m_stream{};
+  std::vector<u32> m_video_buffer;
+
+  u64 m_last_gc_ticks = 0;
+  u64 m_gc_ticks_remainder = 0;
+  u16 m_keys = 0;
+  bool m_link_enabled = false;
+  bool m_force_disconnect = false;
+
+  std::weak_ptr<GBAHostInterface> m_host;
+
+  std::unique_ptr<std::thread> m_thread;
+  bool m_exit_loop = false;
+  bool m_idle = false;
+  std::mutex m_queue_mutex;
+  std::condition_variable m_command_cv;
+  std::queue<Command> m_command_queue;
+
+  std::mutex m_response_mutex;
+  std::condition_variable m_response_cv;
+  bool m_response_ready = false;
+  std::vector<u8> m_response;
+};
+}  // namespace HW::GBA

Source/Core/DolphinLib.props

@@ -264,6 +264,7 @@
     <ClInclude Include="Core\HW\EXI\EXI_DeviceMemoryCard.h" />
     <ClInclude Include="Core\HW\EXI\EXI_DeviceMic.h" />
     <ClInclude Include="Core\HW\EXI\EXI.h" />
+    <ClInclude Include="Core\HW\GBACore.h" />
     <ClInclude Include="Core\HW\GBAPad.h" />
     <ClInclude Include="Core\HW\GBAPadEmu.h" />
     <ClInclude Include="Core\HW\GCKeyboard.h" />
@@ -846,6 +847,7 @@
     <ClCompile Include="Core\HW\EXI\EXI_DeviceMemoryCard.cpp" />
     <ClCompile Include="Core\HW\EXI\EXI_DeviceMic.cpp" />
     <ClCompile Include="Core\HW\EXI\EXI.cpp" />
+    <ClCompile Include="Core\HW\GBACore.cpp" />
     <ClCompile Include="Core\HW\GBAPad.cpp" />
     <ClCompile Include="Core\HW\GBAPadEmu.cpp" />
     <ClCompile Include="Core\HW\GCKeyboard.cpp" />