15 files changed, 231 insertions, 107 deletions

diff --git a/src/citra_qt/bootmanager.cpp b/src/citra_qt/bootmanager.cpp
index 421b2af55..a162e6dfe 100644
--- a/src/citra_qt/bootmanager.cpp
+++ b/src/citra_qt/bootmanager.cpp
@@ -42,7 +42,6 @@ void EmuThread::run()
                     emit CPUStepped();
             }
         }
-        HW::Update();
     }
 
     Core::Stop();
diff --git a/src/citra_qt/debugger/graphics.cpp b/src/citra_qt/debugger/graphics.cpp
index 0f911a015..a86a55404 100644
--- a/src/citra_qt/debugger/graphics.cpp
+++ b/src/citra_qt/debugger/graphics.cpp
@@ -25,16 +25,16 @@ QVariant GPUCommandStreamItemModel::data(const QModelIndex& index, int role) con
         return QVariant();
 
     int command_index = index.row();
-    const GSP_GPU::GXCommand& command = GetDebugger()->ReadGXCommandHistory(command_index);
+    const GSP_GPU::Command& command = GetDebugger()->ReadGXCommandHistory(command_index);
     if (role == Qt::DisplayRole)
     {
-        std::map<GSP_GPU::GXCommandId, const char*> command_names = {
-            { GSP_GPU::GXCommandId::REQUEST_DMA, "REQUEST_DMA" },
-            { GSP_GPU::GXCommandId::SET_COMMAND_LIST_FIRST, "SET_COMMAND_LIST_FIRST" },
-            { GSP_GPU::GXCommandId::SET_MEMORY_FILL, "SET_MEMORY_FILL" },
-            { GSP_GPU::GXCommandId::SET_DISPLAY_TRANSFER, "SET_DISPLAY_TRANSFER" },
-            { GSP_GPU::GXCommandId::SET_TEXTURE_COPY, "SET_TEXTURE_COPY" },
-            { GSP_GPU::GXCommandId::SET_COMMAND_LIST_LAST, "SET_COMMAND_LIST_LAST" }
+        std::map<GSP_GPU::CommandId, const char*> command_names = {
+            { GSP_GPU::CommandId::REQUEST_DMA, "REQUEST_DMA" },
+            { GSP_GPU::CommandId::SET_COMMAND_LIST_FIRST, "SET_COMMAND_LIST_FIRST" },
+            { GSP_GPU::CommandId::SET_MEMORY_FILL, "SET_MEMORY_FILL" },
+            { GSP_GPU::CommandId::SET_DISPLAY_TRANSFER, "SET_DISPLAY_TRANSFER" },
+            { GSP_GPU::CommandId::SET_TEXTURE_COPY, "SET_TEXTURE_COPY" },
+            { GSP_GPU::CommandId::SET_COMMAND_LIST_LAST, "SET_COMMAND_LIST_LAST" }
         };
         const u32* command_data = reinterpret_cast<const u32*>(&command);
         QString str = QString("%1 %2 %3 %4 %5 %6 %7 %8 %9").arg(command_names[command.id])
diff --git a/src/core/core.cpp b/src/core/core.cpp
index 7dc0809d0..fc9909377 100644
--- a/src/core/core.cpp
+++ b/src/core/core.cpp
@@ -26,21 +26,25 @@ ARM_Interface*  g_sys_core      = nullptr;  ///< ARM11 system (OS) core
 /// Run the core CPU loop
 void RunLoop() {
     for (;;){
-        g_app_core->Run(GPU::kFrameTicks);
+        // This function loops for 100 instructions in the CPU before trying to update hardware.
+        // This is a little bit faster than SingleStep, and should be pretty much equivalent. The 
+        // number of instructions chosen is fairly arbitrary, however a large number will more 
+        // drastically affect the frequency of GSP interrupts and likely break things. The point of
+        // this is to just loop in the CPU for more than 1 instruction to reduce overhead and make
+        // it a little bit faster...
+        g_app_core->Run(100);
         HW::Update();
-        Kernel::Reschedule();
+        if (HLE::g_reschedule) {
+            Kernel::Reschedule();
+        }
     }
 }
 
 /// Step the CPU one instruction
 void SingleStep() {
     g_app_core->Step();
-
-    // Update and reschedule after approx. 1 frame
-    u64 current_ticks = Core::g_app_core->GetTicks();
-    if ((current_ticks - g_last_ticks) >= GPU::kFrameTicks || HLE::g_reschedule) {
-        g_last_ticks = current_ticks;
-        HW::Update();
+    HW::Update();
+    if (HLE::g_reschedule) {
         Kernel::Reschedule();
     }
 }
diff --git a/src/core/hle/kernel/address_arbiter.cpp b/src/core/hle/kernel/address_arbiter.cpp
index 61717bbe4..bdf76e0c2 100644
--- a/src/core/hle/kernel/address_arbiter.cpp
+++ b/src/core/hle/kernel/address_arbiter.cpp
@@ -53,7 +53,7 @@ Result ArbitrateAddress(Handle handle, ArbitrationType type, u32 address, s32 va
             for(int i = 0; i < value; i++)
                 ArbitrateHighestPriorityThread(handle, address);
         }
-        HLE::Reschedule(__func__);
+        break;
 
     // Wait current thread (acquire the arbiter)...
     case ArbitrationType::WaitIfLessThan:
@@ -61,6 +61,7 @@ Result ArbitrateAddress(Handle handle, ArbitrationType type, u32 address, s32 va
             Kernel::WaitCurrentThread(WAITTYPE_ARB, handle);
             HLE::Reschedule(__func__);
         }
+        break;
 
     default:
         ERROR_LOG(KERNEL, "unknown type=%d", type);
diff --git a/src/core/hle/kernel/event.cpp b/src/core/hle/kernel/event.cpp
index 127c0cfc6..1e417e09c 100644
--- a/src/core/hle/kernel/event.cpp
+++ b/src/core/hle/kernel/event.cpp
@@ -42,7 +42,7 @@ public:
             if (std::find(waiting_threads.begin(), waiting_threads.end(), thread) == waiting_threads.end()) {
                 waiting_threads.push_back(thread);
             }
-            Kernel::WaitCurrentThread(WAITTYPE_EVENT);
+            Kernel::WaitCurrentThread(WAITTYPE_EVENT, GetHandle());
         }
         if (reset_type != RESETTYPE_STICKY && !permanent_locked) {
             locked = true;
diff --git a/src/core/hle/kernel/mutex.cpp b/src/core/hle/kernel/mutex.cpp
index 1ccf1eb73..055f503f9 100644
--- a/src/core/hle/kernel/mutex.cpp
+++ b/src/core/hle/kernel/mutex.cpp
@@ -48,7 +48,7 @@ public:
         *wait = locked;
 
         if (locked) {
-            Kernel::WaitCurrentThread(WAITTYPE_MUTEX);
+            Kernel::WaitCurrentThread(WAITTYPE_MUTEX, GetHandle());
         }
 
         return 0;
diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
index 86bbf29d0..1d7ded6f6 100644
--- a/src/core/hle/kernel/thread.cpp
+++ b/src/core/hle/kernel/thread.cpp
@@ -274,7 +274,11 @@ Thread* NextThread() {
     return Kernel::g_object_pool.GetFast<Thread>(next);
 }
 
-/// Puts the current thread in the wait state for the given type
+/**
+ * Puts the current thread in the wait state for the given type
+ * @param wait_type Type of wait
+ * @param wait_handle Handle of Kernel object that we are waiting on, defaults to current thread
+ */
 void WaitCurrentThread(WaitType wait_type, Handle wait_handle) {
     Thread* thread = GetCurrentThread();
     thread->wait_type = wait_type;
diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h
index f2bfdfa1a..39fa38b75 100644
--- a/src/core/hle/kernel/thread.h
+++ b/src/core/hle/kernel/thread.h
@@ -69,7 +69,11 @@ void ArbitrateAllThreads(u32 arbiter, u32 address);
 /// Gets the current thread handle
 Handle GetCurrentThreadHandle();
 
-/// Puts the current thread in the wait state for the given type
+/**
+ * Puts the current thread in the wait state for the given type
+ * @param wait_type Type of wait
+ * @param wait_handle Handle of Kernel object that we are waiting on, defaults to current thread
+ */
 void WaitCurrentThread(WaitType wait_type, Handle wait_handle=GetCurrentThreadHandle());
 
 /// Put current thread in a wait state - on WaitSynchronization
diff --git a/src/core/hle/service/gsp.cpp b/src/core/hle/service/gsp.cpp
index b20203e27..e241b31c8 100644
--- a/src/core/hle/service/gsp.cpp
+++ b/src/core/hle/service/gsp.cpp
@@ -11,55 +11,35 @@
 #include "core/hle/kernel/event.h"
 #include "core/hle/kernel/shared_memory.h"
 #include "core/hle/service/gsp.h"
-
 #include "core/hw/gpu.h"
 
 #include "video_core/gpu_debugger.h"
 
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
 // Main graphics debugger object - TODO: Here is probably not the best place for this
 GraphicsDebugger g_debugger;
 
-/// GSP shared memory GX command buffer header
-union GX_CmdBufferHeader {
-    u32 hex;
-
-    // Current command index. This index is updated by GSP module after loading the command data,
-    // right before the command is processed. When this index is updated by GSP module, the total
-    // commands field is decreased by one as well.
-    BitField<0,8,u32>   index;
-
-    // Total commands to process, must not be value 0 when GSP module handles commands. This must be
-    // <=15 when writing a command to shared memory. This is incremented by the application when
-    // writing a command to shared memory, after increasing this value TriggerCmdReqQueue is only
-    // used if this field is value 1.
-    BitField<8,8,u32>   number_commands;
-};
-
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Namespace GSP_GPU
 
 namespace GSP_GPU {
 
-Handle g_event = 0;
-Handle g_shared_memory = 0;
+Handle g_interrupt_event = 0;   ///< Handle to event triggered when GSP interrupt has been signalled
+Handle g_shared_memory = 0;     ///< Handle to GSP shared memorys
+u32 g_thread_id = 1;            ///< Thread index into interrupt relay queue, 1 is arbitrary
 
-u32 g_thread_id = 0;
+/// Gets a pointer to a thread command buffer in GSP shared memory
+static inline u8* GetCommandBuffer(u32 thread_id) {
+    if (0 == g_shared_memory)
+        return nullptr;
 
-/// Gets a pointer to the start (header) of a command buffer in GSP shared memory
-static inline u8* GX_GetCmdBufferPointer(u32 thread_id, u32 offset=0) {
-    return Kernel::GetSharedMemoryPointer(g_shared_memory, 0x800 + (thread_id * 0x200) + offset);
+    return Kernel::GetSharedMemoryPointer(g_shared_memory, 
+        0x800 + (thread_id * sizeof(CommandBuffer)));
 }
 
-/// Finishes execution of a GSP command
-void GX_FinishCommand(u32 thread_id) {
-    GX_CmdBufferHeader* header = (GX_CmdBufferHeader*)GX_GetCmdBufferPointer(thread_id);
-
-    g_debugger.GXCommandProcessed(GX_GetCmdBufferPointer(thread_id, 0x20 + (header->index * 0x20)));
-
-    header->number_commands = header->number_commands - 1;
-    // TODO: Increment header->index?
+/// Gets a pointer to the interrupt relay queue for a given thread index
+static inline InterruptRelayQueue* GetInterruptRelayQueue(u32 thread_id) {
+    return (InterruptRelayQueue*)Kernel::GetSharedMemoryPointer(g_shared_memory,
+        sizeof(InterruptRelayQueue) * thread_id);
 }
 
 /// Write a GSP GPU hardware register
@@ -133,39 +113,55 @@ void ReadHWRegs(Service::Interface* self) {
 void RegisterInterruptRelayQueue(Service::Interface* self) {
     u32* cmd_buff = Service::GetCommandBuffer();
     u32 flags = cmd_buff[1];
-    g_event = cmd_buff[3];
-
-    _assert_msg_(GSP, (g_event != 0), "handle is not valid!");
+    g_interrupt_event = cmd_buff[3];
+    g_shared_memory = Kernel::CreateSharedMemory("GSPSharedMem");
 
-    Kernel::SetEventLocked(g_event, false);
+    _assert_msg_(GSP, (g_interrupt_event != 0), "handle is not valid!");
 
-    // Hack - This function will permanently set the state of the GSP event such that GPU command
-    // synchronization barriers always passthrough. Correct solution would be to set this after the
-    // GPU as processed all queued up commands, but due to the emulator being single-threaded they
-    // will always be ready.
-    Kernel::SetPermanentLock(g_event, true);
+    cmd_buff[2] = g_thread_id++; // ThreadID
+    cmd_buff[4] = g_shared_memory; // GSP shared memory
 
-    cmd_buff[0] = 0;                // Result - no error
-    cmd_buff[2] = g_thread_id;      // ThreadID
-    cmd_buff[4] = g_shared_memory;  // GSP shared memory
+    Kernel::SignalEvent(g_interrupt_event); // TODO(bunnei): Is this correct?
 }
 
+/**
+ * Signals that the specified interrupt type has occurred to userland code
+ * @param interrupt_id ID of interrupt that is being signalled
+ */
+void SignalInterrupt(InterruptId interrupt_id) {
+    if (0 == g_interrupt_event) {
+        WARN_LOG(GSP, "cannot synchronize until GSP event has been created!");
+        return;
+    }
+    if (0 == g_shared_memory) {
+        WARN_LOG(GSP, "cannot synchronize until GSP shared memory has been created!");
+        return;
+    }
+    for (int thread_id = 0; thread_id < 0x4; ++thread_id) {
+        InterruptRelayQueue* interrupt_relay_queue = GetInterruptRelayQueue(thread_id);
+        interrupt_relay_queue->number_interrupts = interrupt_relay_queue->number_interrupts + 1;
 
-/// This triggers handling of the GX command written to the command buffer in shared memory.
-void TriggerCmdReqQueue(Service::Interface* self) {
+        u8 next = interrupt_relay_queue->index;
+        next += interrupt_relay_queue->number_interrupts;
+        next = next % 0x34; // 0x34 is the number of interrupt slots
 
+        interrupt_relay_queue->slot[next] = interrupt_id;
+        interrupt_relay_queue->error_code = 0x0; // No error
+    }
+    Kernel::SignalEvent(g_interrupt_event);
+}
+
+/// Executes the next GSP command
+void ExecuteCommand(const Command& command) {
     // Utility function to convert register ID to address
     auto WriteGPURegister = [](u32 id, u32 data) {
         GPU::Write<u32>(0x1EF00000 + 4 * id, data);
     };
 
-    GX_CmdBufferHeader* header = (GX_CmdBufferHeader*)GX_GetCmdBufferPointer(g_thread_id);
-    auto& command = *(const GXCommand*)GX_GetCmdBufferPointer(g_thread_id, 0x20 + (header->index * 0x20));
-
     switch (command.id) {
 
     // GX request DMA - typically used for copying memory from GSP heap to VRAM
-    case GXCommandId::REQUEST_DMA:
+    case CommandId::REQUEST_DMA:
         memcpy(Memory::GetPointer(command.dma_request.dest_address),
                Memory::GetPointer(command.dma_request.source_address),
                command.dma_request.size);
@@ -174,24 +170,27 @@ void TriggerCmdReqQueue(Service::Interface* self) {
     // ctrulib homebrew sends all relevant command list data with this command,
     // hence we do all "interesting" stuff here and do nothing in SET_COMMAND_LIST_FIRST.
     // TODO: This will need some rework in the future.
-    case GXCommandId::SET_COMMAND_LIST_LAST:
+    case CommandId::SET_COMMAND_LIST_LAST:
     {
         auto& params = command.set_command_list_last;
         WriteGPURegister(GPU::Regs::CommandProcessor + 2, params.address >> 3);
         WriteGPURegister(GPU::Regs::CommandProcessor, params.size >> 3);
-        WriteGPURegister(GPU::Regs::CommandProcessor + 4, 1); // TODO: Not sure if we are supposed to always write this .. seems to trigger processing though
+
+        // TODO: Not sure if we are supposed to always write this .. seems to trigger processing though
+        WriteGPURegister(GPU::Regs::CommandProcessor + 4, 1);
 
         // TODO: Move this to GPU
         // TODO: Not sure what units the size is measured in
         g_debugger.CommandListCalled(params.address,
                                      (u32*)Memory::GetPointer(params.address),
                                      params.size);
+        SignalInterrupt(InterruptId::P3D);
         break;
     }
 
     // It's assumed that the two "blocks" behave equivalently.
     // Presumably this is done simply to allow two memory fills to run in parallel.
-    case GXCommandId::SET_MEMORY_FILL:
+    case CommandId::SET_MEMORY_FILL:
     {
         auto& params = command.memory_fill;
         WriteGPURegister(GPU::Regs::MemoryFill, params.start1 >> 3);
@@ -207,8 +206,18 @@ void TriggerCmdReqQueue(Service::Interface* self) {
     }
 
     // TODO: Check if texture copies are implemented correctly..
-    case GXCommandId::SET_DISPLAY_TRANSFER:
-    case GXCommandId::SET_TEXTURE_COPY:
+    case CommandId::SET_DISPLAY_TRANSFER:
+        // TODO(bunnei): Signalling all of these interrupts here is totally wrong, but it seems to
+        // work well enough for running demos. Need to figure out how these all work and trigger
+        // them correctly.
+        SignalInterrupt(InterruptId::PSC0);
+        SignalInterrupt(InterruptId::PSC1);
+        SignalInterrupt(InterruptId::PPF);
+        SignalInterrupt(InterruptId::P3D);
+        SignalInterrupt(InterruptId::DMA);
+        break;
+
+    case CommandId::SET_TEXTURE_COPY:
     {
         auto& params = command.image_copy;
         WriteGPURegister(GPU::Regs::DisplayTransfer, params.in_buffer_address >> 3);
@@ -225,7 +234,7 @@ void TriggerCmdReqQueue(Service::Interface* self) {
 
     // TODO: Figure out what exactly SET_COMMAND_LIST_FIRST and SET_COMMAND_LIST_LAST
     //       are supposed to do.
-    case GXCommandId::SET_COMMAND_LIST_FIRST:
+    case CommandId::SET_COMMAND_LIST_FIRST:
     {
         break;
     }
@@ -233,8 +242,26 @@ void TriggerCmdReqQueue(Service::Interface* self) {
     default:
         ERROR_LOG(GSP, "unknown command 0x%08X", (int)command.id.Value());
     }
+}
 
-    GX_FinishCommand(g_thread_id);
+/// This triggers handling of the GX command written to the command buffer in shared memory.
+void TriggerCmdReqQueue(Service::Interface* self) {
+
+    // Iterate through each thread's command queue...
+    for (unsigned thread_id = 0; thread_id < 0x4; ++thread_id) {
+        CommandBuffer* command_buffer = (CommandBuffer*)GetCommandBuffer(thread_id);
+
+        // Iterate through each command...
+        for (unsigned i = 0; i < command_buffer->number_commands; ++i) {
+            g_debugger.GXCommandProcessed((u8*)&command_buffer->commands[i]);
+
+            // Decode and execute command
+            ExecuteCommand(command_buffer->commands[i]);
+
+            // Indicates that command has completed
+            command_buffer->number_commands = command_buffer->number_commands - 1;
+        }
+    }
 }
 
 const Interface::FunctionInfo FunctionTable[] = {
@@ -275,7 +302,10 @@ const Interface::FunctionInfo FunctionTable[] = {
 
 Interface::Interface() {
     Register(FunctionTable, ARRAY_SIZE(FunctionTable));
-    g_shared_memory = Kernel::CreateSharedMemory("GSPSharedMem");
+
+    g_interrupt_event = 0;
+    g_shared_memory = 0;
+    g_thread_id = 1;
 }
 
 Interface::~Interface() {
diff --git a/src/core/hle/service/gsp.h b/src/core/hle/service/gsp.h
index a83cb4846..fccebef7e 100644
--- a/src/core/hle/service/gsp.h
+++ b/src/core/hle/service/gsp.h
@@ -12,7 +12,19 @@
 
 namespace GSP_GPU {
 
-enum class GXCommandId : u32 {
+/// GSP interrupt ID
+enum class InterruptId : u8 {
+    PSC0    = 0x00,
+    PSC1    = 0x01,
+    PDC0    = 0x02, // Seems called every vertical screen line
+    PDC1    = 0x03, // Seems called every frame
+    PPF     = 0x04,
+    P3D     = 0x05,
+    DMA     = 0x06,
+};
+
+/// GSP command ID
+enum class CommandId : u32 {
     REQUEST_DMA            = 0x00,
     SET_COMMAND_LIST_LAST  = 0x01,
 
@@ -29,8 +41,32 @@ enum class GXCommandId : u32 {
     SET_COMMAND_LIST_FIRST = 0x05,
 };
 
-struct GXCommand {
-    BitField<0, 8, GXCommandId> id;
+/// GSP thread interrupt relay queue
+struct InterruptRelayQueue {
+    union {
+        u32 hex;
+
+        // Index of last interrupt in the queue
+        BitField<0,8,u32>   index;
+
+        // Number of interrupts remaining to be processed by the userland code
+        BitField<8,8,u32>   number_interrupts;
+
+        // Error code - zero on success, otherwise an error has occurred
+        BitField<16,8,u32>  error_code;
+    };
+
+    u32 unk0;
+    u32 unk1;
+
+    InterruptId slot[0x34];   ///< Interrupt ID slots
+};
+static_assert(sizeof(InterruptRelayQueue) == 0x40,
+    "InterruptRelayQueue struct has incorrect size");
+
+/// GSP command
+struct Command {
+    BitField<0, 8, CommandId> id;
 
     union {
         struct {
@@ -64,7 +100,30 @@ struct GXCommand {
         u8 raw_data[0x1C];
     };
 };
-static_assert(sizeof(GXCommand) == 0x20, "GXCommand struct has incorrect size");
+static_assert(sizeof(Command) == 0x20, "Command struct has incorrect size");
+
+/// GSP shared memory GX command buffer header
+struct CommandBuffer {
+    union {
+        u32 hex;
+
+        // Current command index. This index is updated by GSP module after loading the command
+        // data, right before the command is processed. When this index is updated by GSP module,
+        // the total commands field is decreased by one as well.
+        BitField<0,8,u32>   index;
+
+        // Total commands to process, must not be value 0 when GSP module handles commands. This
+        // must be <=15 when writing a command to shared memory. This is incremented by the
+        // application when writing a command to shared memory, after increasing this value
+        // TriggerCmdReqQueue is only used if this field is value 1.
+        BitField<8,8,u32>   number_commands;
+    };
+
+    u32 unk[7];
+
+    Command commands[0xF];
+};
+static_assert(sizeof(CommandBuffer) == 0x200, "CommandBuffer struct has incorrect size");
 
 /// Interface to "srv:" service
 class Interface : public Service::Interface {
@@ -84,4 +143,10 @@ public:
 
 };
 
+/**
+ * Signals that the specified interrupt type has occurred to userland code
+ * @param interrupt_id ID of interrupt that is being signalled
+ */
+void SignalInterrupt(InterruptId interrupt_id);
+
 } // namespace
diff --git a/src/core/hle/service/srv.cpp b/src/core/hle/service/srv.cpp
index f45c0efc2..8f8413d02 100644
--- a/src/core/hle/service/srv.cpp
+++ b/src/core/hle/service/srv.cpp
@@ -5,28 +5,30 @@
 #include "core/hle/hle.h"
 #include "core/hle/service/srv.h"
 #include "core/hle/service/service.h"
-#include "core/hle/kernel/mutex.h"
+#include "core/hle/kernel/event.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Namespace SRV
 
 namespace SRV {
 
-Handle g_mutex = 0;
+Handle g_event_handle = 0;
 
 void Initialize(Service::Interface* self) {
     DEBUG_LOG(OSHLE, "called");
-    if (!g_mutex) {
-        g_mutex = Kernel::CreateMutex(true, "SRV:Lock");
-    }
 }
 
 void GetProcSemaphore(Service::Interface* self) {
     DEBUG_LOG(OSHLE, "called");
-    // Get process semaphore?
+
     u32* cmd_buff = Service::GetCommandBuffer();
-    cmd_buff[1] = 0;        // No error
-    cmd_buff[3] = g_mutex;  // Return something... 0 == nullptr, raises an exception
+
+    // TODO(bunnei): Change to a semaphore once these have been implemented
+    g_event_handle = Kernel::CreateEvent(RESETTYPE_ONESHOT, "SRV:Event");
+    Kernel::SetEventLocked(g_event_handle, false);
+
+    cmd_buff[1] = 0; // No error
+    cmd_buff[3] = g_event_handle;
 }
 
 void GetServiceHandle(Service::Interface* self) {
diff --git a/src/core/hle/svc.cpp b/src/core/hle/svc.cpp
index 17967f260..328d048bd 100644
--- a/src/core/hle/svc.cpp
+++ b/src/core/hle/svc.cpp
@@ -185,8 +185,6 @@ Result CreateAddressArbiter(u32* arbiter) {
 
 /// Arbitrate address
 Result ArbitrateAddress(Handle arbiter, u32 address, u32 type, u32 value, s64 nanoseconds) {
-    DEBUG_LOG(SVC, "called arbiter=0x%08X, address=0x%08X, type=0x%08X, value=0x%08X, "
-        "nanoseconds=%d", arbiter, address, type, value, nanoseconds);
     return Kernel::ArbitrateAddress(arbiter, static_cast<Kernel::ArbitrationType>(type), address, 
         value);
 }
diff --git a/src/core/hw/gpu.cpp b/src/core/hw/gpu.cpp
index c00be2a83..d94c2329b 100644
--- a/src/core/hw/gpu.cpp
+++ b/src/core/hw/gpu.cpp
@@ -7,7 +7,11 @@
 
 #include "core/core.h"
 #include "core/mem_map.h"
+
+#include "core/hle/hle.h"
 #include "core/hle/kernel/thread.h"
+#include "core/hle/service/gsp.h"
+
 #include "core/hw/gpu.h"
 
 #include "video_core/video_core.h"
@@ -17,7 +21,8 @@ namespace GPU {
 
 RegisterSet<u32, Regs> g_regs;
 
-u64 g_last_ticks = 0; ///< Last CPU ticks
+u32 g_cur_line = 0;         ///< Current vertical screen line
+u64 g_last_line_ticks = 0;  ///< CPU tick count from last vertical screen line
 
 /**
  * Sets whether the framebuffers are in the GSP heap (FCRAM) or VRAM
@@ -247,19 +252,31 @@ template void Write<u8>(u32 addr, const u8 data);
 
 /// Update hardware
 void Update() {
+    auto& framebuffer_top = g_regs.Get<Regs::FramebufferTop>();
     u64 current_ticks = Core::g_app_core->GetTicks();
 
-    // Fake a vertical blank
-    if ((current_ticks - g_last_ticks) >= kFrameTicks) {
-        g_last_ticks = current_ticks;
+    // Synchronize line...
+    if ((current_ticks - g_last_line_ticks) >= GPU::kFrameTicks / framebuffer_top.height) {
+        GSP_GPU::SignalInterrupt(GSP_GPU::InterruptId::PDC0);
+        g_cur_line++;
+        g_last_line_ticks = current_ticks;
+    }
+
+    // Synchronize frame...
+    if (g_cur_line >= framebuffer_top.height) {
+        g_cur_line = 0;
+        GSP_GPU::SignalInterrupt(GSP_GPU::InterruptId::PDC1);
         VideoCore::g_renderer->SwapBuffers();
         Kernel::WaitCurrentThread(WAITTYPE_VBLANK);
+        HLE::Reschedule(__func__);
     }
 }
 
 /// Initialize hardware
 void Init() {
-    g_last_ticks = Core::g_app_core->GetTicks();
+    g_cur_line = 0;
+    g_last_line_ticks = Core::g_app_core->GetTicks();
+
 //    SetFramebufferLocation(FRAMEBUFFER_LOCATION_FCRAM);
     SetFramebufferLocation(FRAMEBUFFER_LOCATION_VRAM);
 
diff --git a/src/core/mem_map_funcs.cpp b/src/core/mem_map_funcs.cpp
index 038d3bffa..305be8468 100644
--- a/src/core/mem_map_funcs.cpp
+++ b/src/core/mem_map_funcs.cpp
@@ -168,7 +168,7 @@ u8 *GetPointer(const u32 addr) {
          return g_system_mem + (vaddr & SYSTEM_MEMORY_MASK);
 
     // VRAM
-    } else if ((vaddr > VRAM_VADDR)  && (vaddr < VRAM_VADDR_END)) {
+    } else if ((vaddr >= VRAM_VADDR)  && (vaddr < VRAM_VADDR_END)) {
         return g_vram + (vaddr & VRAM_MASK);
 
     } else {
diff --git a/src/video_core/gpu_debugger.h b/src/video_core/gpu_debugger.h
index d92ceaa72..5d85f90b9 100644
--- a/src/video_core/gpu_debugger.h
+++ b/src/video_core/gpu_debugger.h
@@ -49,7 +49,7 @@ public:
         */
         virtual void GXCommandProcessed(int total_command_count)
         {
-            const GSP_GPU::GXCommand& cmd = observed->ReadGXCommandHistory(total_command_count-1);
+            const GSP_GPU::Command& cmd = observed->ReadGXCommandHistory(total_command_count-1);
             ERROR_LOG(GSP, "Received command: id=%x", (int)cmd.id.Value());
         }
 
@@ -81,10 +81,10 @@ public:
         if (observers.empty())
             return;
 
-        gx_command_history.push_back(GSP_GPU::GXCommand());
-        GSP_GPU::GXCommand& cmd = gx_command_history[gx_command_history.size()-1];
+        gx_command_history.push_back(GSP_GPU::Command());
+        GSP_GPU::Command& cmd = gx_command_history[gx_command_history.size()-1];
 
-        memcpy(&cmd, command_data, sizeof(GSP_GPU::GXCommand));
+        memcpy(&cmd, command_data, sizeof(GSP_GPU::Command));
 
         ForEachObserver([this](DebuggerObserver* observer) {
                           observer->GXCommandProcessed(this->gx_command_history.size());
@@ -123,7 +123,7 @@ public:
                         } );
     }
 
-    const GSP_GPU::GXCommand& ReadGXCommandHistory(int index) const
+    const GSP_GPU::Command& ReadGXCommandHistory(int index) const
     {
         // TODO: Is this thread-safe?
         return gx_command_history[index];
@@ -155,7 +155,7 @@ private:
 
     std::vector<DebuggerObserver*> observers;
 
-    std::vector<GSP_GPU::GXCommand> gx_command_history;
+    std::vector<GSP_GPU::Command> gx_command_history;
 
     // vector of pairs of command lists and their storage address
     std::vector<std::pair<u32,PicaCommandList>> command_lists;