SI: Implement GBAEmu device

9 files changed, 237 insertions, 3 deletions

diff --git a/Source/Core/AudioCommon/AudioCommon.cpp b/Source/Core/AudioCommon/AudioCommon.cpp
index cfa5383c7c..6623b5ad8b 100644
--- a/Source/Core/AudioCommon/AudioCommon.cpp
+++ b/Source/Core/AudioCommon/AudioCommon.cpp
@@ -68,7 +68,8 @@ void InitSoundStream()
 
 void PostInitSoundStream()
 {
-  // This needs to be called after AudioInterface::Init where input sample rates are set
+  // This needs to be called after AudioInterface::Init and SerialInterface::Init (for GBA devices)
+  // where input sample rates are set
   UpdateSoundStream();
   SetSoundStreamRunning(true);
 
diff --git a/Source/Core/Core/CMakeLists.txt b/Source/Core/Core/CMakeLists.txt
index 65eb857982..0ae84e2bdc 100644
--- a/Source/Core/Core/CMakeLists.txt
+++ b/Source/Core/Core/CMakeLists.txt
@@ -624,6 +624,8 @@ if(USE_MGBA)
   target_sources(core PRIVATE
     HW/GBACore.cpp
     HW/GBACore.h
+    HW/SI/SI_DeviceGBAEmu.cpp
+    HW/SI/SI_DeviceGBAEmu.h
   )
   target_link_libraries(core PUBLIC mGBA::mgba)
   target_compile_definitions(core PUBLIC -DHAS_LIBMGBA)
diff --git a/Source/Core/Core/HW/SI/SI.cpp b/Source/Core/Core/HW/SI/SI.cpp
index 14e586fc05..caaa95cbae 100644
--- a/Source/Core/Core/HW/SI/SI.cpp
+++ b/Source/Core/Core/HW/SI/SI.cpp
@@ -707,7 +707,7 @@ void UpdateDevices()
 
 SIDevices GetDeviceType(int channel)
 {
-  if (channel < 0 || channel > 3)
+  if (channel < 0 || channel >= MAX_SI_CHANNELS || !s_channel[channel].device)
     return SIDEVICE_NONE;
 
   return s_channel[channel].device->GetDeviceType();
diff --git a/Source/Core/Core/HW/SI/SI_Device.cpp b/Source/Core/Core/HW/SI/SI_Device.cpp
index 401b1178a7..fa823ff8ad 100644
--- a/Source/Core/Core/HW/SI/SI_Device.cpp
+++ b/Source/Core/Core/HW/SI/SI_Device.cpp
@@ -13,8 +13,12 @@
 
 #include "Common/CommonTypes.h"
 #include "Common/Logging/Log.h"
+#include "Common/MsgHandler.h"
 #include "Core/HW/SI/SI_DeviceDanceMat.h"
 #include "Core/HW/SI/SI_DeviceGBA.h"
+#ifdef HAS_LIBMGBA
+#include "Core/HW/SI/SI_DeviceGBAEmu.h"
+#endif
 #include "Core/HW/SI/SI_DeviceGCAdapter.h"
 #include "Core/HW/SI/SI_DeviceGCController.h"
 #include "Core/HW/SI/SI_DeviceGCSteeringWheel.h"
@@ -187,6 +191,14 @@ std::unique_ptr<ISIDevice> SIDevice_Create(const SIDevices device, const int por
   case SIDEVICE_GC_GBA:
     return std::make_unique<CSIDevice_GBA>(device, port_number);
 
+  case SIDEVICE_GC_GBA_EMULATED:
+#ifdef HAS_LIBMGBA
+    return std::make_unique<CSIDevice_GBAEmu>(device, port_number);
+#else
+    PanicAlertT("Error: This build does not support emulated GBA controllers");
+    return std::make_unique<CSIDevice_Null>(device, port_number);
+#endif
+
   case SIDEVICE_GC_KEYBOARD:
     return std::make_unique<CSIDevice_Keyboard>(device, port_number);
 
diff --git a/Source/Core/Core/HW/SI/SI_Device.h b/Source/Core/Core/HW/SI/SI_Device.h
index c2ae9bef87..d109432b90 100644
--- a/Source/Core/Core/HW/SI/SI_Device.h
+++ b/Source/Core/Core/HW/SI/SI_Device.h
@@ -93,6 +93,7 @@ enum SIDevices : int
   // It's kept here so that values below will stay constant.
   SIDEVICE_AM_BASEBOARD,
   SIDEVICE_WIIU_ADAPTER,
+  SIDEVICE_GC_GBA_EMULATED,
   // Not a valid device. Used for checking whether enum values are valid.
   SIDEVICE_COUNT,
 };
diff --git a/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.cpp b/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.cpp
new file mode 100644
index 0000000000..aaf971b45e
--- /dev/null
+++ b/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.cpp
@@ -0,0 +1,167 @@
+// Copyright 2021 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <vector>
+
+#include "Common/ChunkFile.h"
+#include "Common/CommonTypes.h"
+#include "Common/Logging/Log.h"
+#include "Common/Swap.h"
+#include "Core/Core.h"
+#include "Core/CoreTiming.h"
+#include "Core/HW/GBACore.h"
+#include "Core/HW/GBAPad.h"
+#include "Core/HW/SI/SI.h"
+#include "Core/HW/SI/SI_DeviceGBAEmu.h"
+#include "Core/HW/SI/SI_DeviceGCController.h"
+#include "Core/HW/SystemTimers.h"
+#include "Core/Host.h"
+#include "Core/NetPlayProto.h"
+
+namespace SerialInterface
+{
+static s64 GetSyncInterval()
+{
+  return SystemTimers::GetTicksPerSecond() / 1000;
+}
+
+CSIDevice_GBAEmu::CSIDevice_GBAEmu(SIDevices device, int device_number)
+    : ISIDevice(device, device_number)
+{
+  m_core = std::make_shared<HW::GBA::Core>(m_device_number);
+  m_core->Start(CoreTiming::GetTicks());
+  m_gbahost = Host_CreateGBAHost(m_core);
+  m_core->SetHost(m_gbahost);
+  ScheduleEvent(m_device_number, GetSyncInterval());
+}
+
+CSIDevice_GBAEmu::~CSIDevice_GBAEmu()
+{
+  RemoveEvent(m_device_number);
+  m_core->Stop();
+  m_gbahost.reset();
+  m_core.reset();
+}
+
+int CSIDevice_GBAEmu::RunBuffer(u8* buffer, int request_length)
+{
+  switch (m_next_action)
+  {
+  case NextAction::SendCommand:
+  {
+#ifdef _DEBUG
+    NOTICE_LOG_FMT(SERIALINTERFACE, "{} cmd {:02x} [> {:02x}{:02x}{:02x}{:02x}]", m_device_number,
+                   buffer[0], buffer[1], buffer[2], buffer[3], buffer[4]);
+#endif
+    m_last_cmd = static_cast<EBufferCommands>(buffer[0]);
+    m_timestamp_sent = CoreTiming::GetTicks();
+    m_core->SendJoybusCommand(m_timestamp_sent, TransferInterval(), buffer, m_keys);
+
+    RemoveEvent(m_device_number);
+    ScheduleEvent(m_device_number, TransferInterval() + GetSyncInterval());
+    for (int i = 0; i < MAX_SI_CHANNELS; ++i)
+    {
+      if (i == m_device_number || SerialInterface::GetDeviceType(i) != GetDeviceType())
+        continue;
+      RemoveEvent(i);
+      ScheduleEvent(i, 0, static_cast<u64>(TransferInterval()));
+    }
+
+    m_next_action = NextAction::WaitTransferTime;
+    [[fallthrough]];
+  }
+
+  case NextAction::WaitTransferTime:
+  {
+    int elapsed_time = static_cast<int>(CoreTiming::GetTicks() - m_timestamp_sent);
+    // Tell SI to ask again after TransferInterval() cycles
+    if (TransferInterval() > elapsed_time)
+      return 0;
+    m_next_action = NextAction::ReceiveResponse;
+    [[fallthrough]];
+  }
+
+  case NextAction::ReceiveResponse:
+  {
+    m_next_action = NextAction::SendCommand;
+
+    std::vector<u8> response = m_core->GetJoybusResponse();
+    if (response.empty())
+      return -1;
+    std::copy(response.begin(), response.end(), buffer);
+
+#ifdef _DEBUG
+    const Common::Log::LOG_LEVELS log_level =
+        (m_last_cmd == EBufferCommands::CMD_STATUS || m_last_cmd == EBufferCommands::CMD_RESET) ?
+            Common::Log::LERROR :
+            Common::Log::LWARNING;
+    GENERIC_LOG_FMT(Common::Log::SERIALINTERFACE, log_level,
+                    "{}                              [< {:02x}{:02x}{:02x}{:02x}{:02x}] ({})",
+                    m_device_number, buffer[0], buffer[1], buffer[2], buffer[3], buffer[4],
+                    response.size());
+#endif
+
+    return static_cast<int>(response.size());
+  }
+  }
+
+  // This should never happen, but appease MSVC which thinks it might.
+  ERROR_LOG_FMT(SERIALINTERFACE, "Unknown state {}\n", m_next_action);
+  return -1;
+}
+
+int CSIDevice_GBAEmu::TransferInterval()
+{
+  return SIDevice_GetGBATransferTime(m_last_cmd);
+}
+
+bool CSIDevice_GBAEmu::GetData(u32& hi, u32& low)
+{
+  GCPadStatus pad_status{};
+  if (!NetPlay::IsNetPlayRunning())
+    pad_status = Pad::GetGBAStatus(m_device_number);
+  SerialInterface::CSIDevice_GCController::HandleMoviePadStatus(m_device_number, &pad_status);
+
+  static constexpr std::array<PadButton, 10> buttons_map = {
+      PadButton::PAD_BUTTON_A,      // A
+      PadButton::PAD_BUTTON_B,      // B
+      PadButton::PAD_TRIGGER_Z,     // Select
+      PadButton::PAD_BUTTON_START,  // Start
+      PadButton::PAD_BUTTON_RIGHT,  // Right
+      PadButton::PAD_BUTTON_LEFT,   // Left
+      PadButton::PAD_BUTTON_UP,     // Up
+      PadButton::PAD_BUTTON_DOWN,   // Down
+      PadButton::PAD_TRIGGER_R,     // R
+      PadButton::PAD_TRIGGER_L,     // L
+  };
+
+  m_keys = 0;
+  for (size_t i = 0; i < buttons_map.size(); ++i)
+    m_keys |= static_cast<u16>(static_cast<bool>((pad_status.button & buttons_map[i]))) << i;
+
+  // Use X button as a reset signal for NetPlay/Movies
+  if (pad_status.button & PadButton::PAD_BUTTON_X)
+    m_core->Reset();
+
+  return false;
+}
+
+void CSIDevice_GBAEmu::SendCommand(u32 command, u8 poll)
+{
+}
+
+void CSIDevice_GBAEmu::DoState(PointerWrap& p)
+{
+  p.Do(m_next_action);
+  p.Do(m_last_cmd);
+  p.Do(m_timestamp_sent);
+  p.Do(m_keys);
+  m_core->DoState(p);
+}
+
+void CSIDevice_GBAEmu::OnEvent(u64 userdata, s64 cycles_late)
+{
+  m_core->SendJoybusCommand(CoreTiming::GetTicks() + userdata, 0, nullptr, m_keys);
+  ScheduleEvent(m_device_number, userdata + GetSyncInterval());
+}
+}  // namespace SerialInterface
diff --git a/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.h b/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.h
new file mode 100644
index 0000000000..d19c43e27b
--- /dev/null
+++ b/Source/Core/Core/HW/SI/SI_DeviceGBAEmu.h
@@ -0,0 +1,49 @@
+// Copyright 2021 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <memory>
+
+#include "Common/CommonTypes.h"
+#include "Core/HW/SI/SI_Device.h"
+
+namespace HW::GBA
+{
+class Core;
+}  // namespace HW::GBA
+
+class GBAHostInterface;
+
+namespace SerialInterface
+{
+class CSIDevice_GBAEmu : public ISIDevice
+{
+public:
+  CSIDevice_GBAEmu(SIDevices device, int device_number);
+  ~CSIDevice_GBAEmu();
+
+  int RunBuffer(u8* buffer, int request_length) override;
+  int TransferInterval() override;
+  bool GetData(u32& hi, u32& low) override;
+  void SendCommand(u32 command, u8 poll) override;
+  void DoState(PointerWrap& p) override;
+  void OnEvent(u64 userdata, s64 cycles_late) override;
+
+private:
+  enum class NextAction
+  {
+    SendCommand,
+    WaitTransferTime,
+    ReceiveResponse
+  };
+
+  NextAction m_next_action = NextAction::SendCommand;
+  EBufferCommands m_last_cmd{};
+  u64 m_timestamp_sent = 0;
+  u16 m_keys = 0;
+
+  std::shared_ptr<HW::GBA::Core> m_core;
+  std::shared_ptr<GBAHostInterface> m_gbahost;
+};
+}  // namespace SerialInterface
diff --git a/Source/Core/Core/State.cpp b/Source/Core/Core/State.cpp
index 5d5f6e9d33..77e31e1ac0 100644
--- a/Source/Core/Core/State.cpp
+++ b/Source/Core/Core/State.cpp
@@ -73,7 +73,7 @@ static Common::Event g_compressAndDumpStateSyncEvent;
 static std::thread g_save_thread;
 
 // Don't forget to increase this after doing changes on the savestate system
-constexpr u32 STATE_VERSION = 132;  // Last changed in PR 9532
+constexpr u32 STATE_VERSION = 133;  // Last changed in PR 9600
 
 // Maps savestate versions to Dolphin versions.
 // Versions after 42 don't need to be added to this list,
diff --git a/Source/Core/DolphinLib.props b/Source/Core/DolphinLib.props
index 7835689d55..0f0dfe227b 100644
--- a/Source/Core/DolphinLib.props
+++ b/Source/Core/DolphinLib.props
@@ -287,6 +287,7 @@
     <ClInclude Include="Core\HW\SI\SI_Device.h" />
     <ClInclude Include="Core\HW\SI\SI_DeviceDanceMat.h" />
     <ClInclude Include="Core\HW\SI\SI_DeviceGBA.h" />
+    <ClInclude Include="Core\HW\SI\SI_DeviceGBAEmu.h" />
     <ClInclude Include="Core\HW\SI\SI_DeviceGCAdapter.h" />
     <ClInclude Include="Core\HW\SI\SI_DeviceGCController.h" />
     <ClInclude Include="Core\HW\SI\SI_DeviceGCSteeringWheel.h" />
@@ -868,6 +869,7 @@
     <ClCompile Include="Core\HW\SI\SI_Device.cpp" />
     <ClCompile Include="Core\HW\SI\SI_DeviceDanceMat.cpp" />
     <ClCompile Include="Core\HW\SI\SI_DeviceGBA.cpp" />
+    <ClCompile Include="Core\HW\SI\SI_DeviceGBAEmu.cpp" />
     <ClCompile Include="Core\HW\SI\SI_DeviceGCAdapter.cpp" />
     <ClCompile Include="Core\HW\SI\SI_DeviceGCController.cpp" />
     <ClCompile Include="Core\HW\SI\SI_DeviceGCSteeringWheel.cpp" />