Duckstation/src/core/gpu_backend.cpp

319 lines
8.6 KiB
C++

#include "gpu_backend.h"
#include "common/align.h"
#include "common/log.h"
#include "common/state_wrapper.h"
#include "settings.h"
Log_SetChannel(GPUBackend);
std::unique_ptr<GPUBackend> g_gpu_backend;
GPUBackend::GPUBackend() = default;
GPUBackend::~GPUBackend() = default;
bool GPUBackend::Initialize()
{
if (g_settings.gpu_use_thread)
StartGPUThread();
return true;
}
void GPUBackend::Reset()
{
Sync();
m_drawing_area = {};
}
void GPUBackend::UpdateSettings()
{
Sync();
if (m_use_gpu_thread != g_settings.gpu_use_thread)
{
if (!g_settings.gpu_use_thread)
StopGPUThread();
else
StartGPUThread();
}
}
void GPUBackend::Shutdown()
{
StopGPUThread();
}
GPUBackendFillVRAMCommand* GPUBackend::NewFillVRAMCommand()
{
return static_cast<GPUBackendFillVRAMCommand*>(
AllocateCommand(GPUBackendCommandType::FillVRAM, sizeof(GPUBackendFillVRAMCommand)));
}
GPUBackendUpdateVRAMCommand* GPUBackend::NewUpdateVRAMCommand(u32 num_words)
{
const u32 size = sizeof(GPUBackendUpdateVRAMCommand) + (num_words * sizeof(u16));
GPUBackendUpdateVRAMCommand* cmd =
static_cast<GPUBackendUpdateVRAMCommand*>(AllocateCommand(GPUBackendCommandType::UpdateVRAM, size));
return cmd;
}
GPUBackendCopyVRAMCommand* GPUBackend::NewCopyVRAMCommand()
{
return static_cast<GPUBackendCopyVRAMCommand*>(
AllocateCommand(GPUBackendCommandType::CopyVRAM, sizeof(GPUBackendCopyVRAMCommand)));
}
GPUBackendSetDrawingAreaCommand* GPUBackend::NewSetDrawingAreaCommand()
{
return static_cast<GPUBackendSetDrawingAreaCommand*>(
AllocateCommand(GPUBackendCommandType::SetDrawingArea, sizeof(GPUBackendSetDrawingAreaCommand)));
}
GPUBackendDrawPolygonCommand* GPUBackend::NewDrawPolygonCommand(u32 num_vertices)
{
const u32 size = sizeof(GPUBackendDrawPolygonCommand) + (num_vertices * sizeof(GPUBackendDrawPolygonCommand::Vertex));
GPUBackendDrawPolygonCommand* cmd =
static_cast<GPUBackendDrawPolygonCommand*>(AllocateCommand(GPUBackendCommandType::DrawPolygon, size));
cmd->num_vertices = Truncate16(num_vertices);
return cmd;
}
GPUBackendDrawRectangleCommand* GPUBackend::NewDrawRectangleCommand()
{
return static_cast<GPUBackendDrawRectangleCommand*>(
AllocateCommand(GPUBackendCommandType::DrawRectangle, sizeof(GPUBackendDrawRectangleCommand)));
}
GPUBackendDrawLineCommand* GPUBackend::NewDrawLineCommand(u32 num_vertices)
{
const u32 size = sizeof(GPUBackendDrawLineCommand) + (num_vertices * sizeof(GPUBackendDrawLineCommand::Vertex));
GPUBackendDrawLineCommand* cmd =
static_cast<GPUBackendDrawLineCommand*>(AllocateCommand(GPUBackendCommandType::DrawLine, size));
cmd->num_vertices = Truncate16(num_vertices);
return cmd;
}
void* GPUBackend::AllocateCommand(GPUBackendCommandType command, u32 size)
{
// Ensure size is a multiple of 4 so we don't end up with an unaligned command.
size = Common::AlignUpPow2(size, 4);
for (;;)
{
u32 read_ptr = m_command_fifo_read_ptr.load();
u32 write_ptr = m_command_fifo_write_ptr.load();
if (read_ptr > write_ptr)
{
u32 available_size = read_ptr - write_ptr;
while (available_size < (size + sizeof(GPUBackendCommandType)))
{
WakeGPUThread();
read_ptr = m_command_fifo_read_ptr.load();
available_size = (read_ptr > write_ptr) ? (read_ptr - write_ptr) : (COMMAND_QUEUE_SIZE - write_ptr);
}
}
else
{
const u32 available_size = COMMAND_QUEUE_SIZE - write_ptr;
if ((size + sizeof(GPUBackendCommand)) > available_size)
{
// allocate a dummy command to wrap the buffer around
GPUBackendCommand* dummy_cmd = reinterpret_cast<GPUBackendCommand*>(&m_command_fifo_data[write_ptr]);
dummy_cmd->type = GPUBackendCommandType::Wraparound;
dummy_cmd->size = available_size;
dummy_cmd->params.bits = 0;
m_command_fifo_write_ptr.store(0);
continue;
}
}
GPUBackendCommand* cmd = reinterpret_cast<GPUBackendCommand*>(&m_command_fifo_data[write_ptr]);
cmd->type = command;
cmd->size = size;
return cmd;
}
}
u32 GPUBackend::GetPendingCommandSize() const
{
const u32 read_ptr = m_command_fifo_read_ptr.load();
const u32 write_ptr = m_command_fifo_write_ptr.load();
return (write_ptr >= read_ptr) ? (write_ptr - read_ptr) : (COMMAND_QUEUE_SIZE - read_ptr + write_ptr);
}
void GPUBackend::PushCommand(GPUBackendCommand* cmd)
{
if (!m_use_gpu_thread)
{
// single-thread mode
if (cmd->type != GPUBackendCommandType::Sync)
HandleCommand(cmd);
}
else
{
const u32 new_write_ptr = m_command_fifo_write_ptr.fetch_add(cmd->size) + cmd->size;
DebugAssert(new_write_ptr <= COMMAND_QUEUE_SIZE);
if (GetPendingCommandSize() >= THRESHOLD_TO_WAKE_GPU)
WakeGPUThread();
}
}
void GPUBackend::WakeGPUThread()
{
std::unique_lock<std::mutex> lock(m_sync_mutex);
if (!m_gpu_thread_sleeping.load())
return;
m_wake_gpu_thread_cv.notify_one();
}
void GPUBackend::StartGPUThread()
{
m_gpu_loop_done.store(false);
m_use_gpu_thread = true;
m_gpu_thread = std::thread(&GPUBackend::RunGPULoop, this);
Log_InfoPrint("GPU thread started.");
}
void GPUBackend::StopGPUThread()
{
if (!m_use_gpu_thread)
return;
m_gpu_loop_done.store(true);
WakeGPUThread();
m_gpu_thread.join();
m_use_gpu_thread = false;
Log_InfoPrint("GPU thread stopped.");
}
void GPUBackend::Sync()
{
if (!m_use_gpu_thread)
return;
GPUBackendSyncCommand* cmd =
static_cast<GPUBackendSyncCommand*>(AllocateCommand(GPUBackendCommandType::Sync, sizeof(GPUBackendSyncCommand)));
PushCommand(cmd);
WakeGPUThread();
m_sync_event.Wait();
m_sync_event.Reset();
}
void GPUBackend::RunGPULoop()
{
for (;;)
{
u32 write_ptr = m_command_fifo_write_ptr.load();
u32 read_ptr = m_command_fifo_read_ptr.load();
if (read_ptr == write_ptr)
{
std::unique_lock<std::mutex> lock(m_sync_mutex);
m_gpu_thread_sleeping.store(true);
m_wake_gpu_thread_cv.wait(lock, [this]() { return m_gpu_loop_done.load() || GetPendingCommandSize() > 0; });
m_gpu_thread_sleeping.store(false);
if (m_gpu_loop_done.load())
break;
else
continue;
}
if (write_ptr < read_ptr)
write_ptr = COMMAND_QUEUE_SIZE;
while (read_ptr < write_ptr)
{
const GPUBackendCommand* cmd = reinterpret_cast<const GPUBackendCommand*>(&m_command_fifo_data[read_ptr]);
read_ptr += cmd->size;
switch (cmd->type)
{
case GPUBackendCommandType::Wraparound:
{
DebugAssert(read_ptr == COMMAND_QUEUE_SIZE);
write_ptr = m_command_fifo_write_ptr.load();
read_ptr = 0;
}
break;
case GPUBackendCommandType::Sync:
{
DebugAssert(read_ptr == write_ptr);
m_sync_event.Signal();
}
break;
default:
HandleCommand(cmd);
break;
}
}
m_command_fifo_read_ptr.store(read_ptr);
}
}
void GPUBackend::HandleCommand(const GPUBackendCommand* cmd)
{
switch (cmd->type)
{
case GPUBackendCommandType::FillVRAM:
{
FlushRender();
const GPUBackendFillVRAMCommand* ccmd = static_cast<const GPUBackendFillVRAMCommand*>(cmd);
FillVRAM(ZeroExtend32(ccmd->x), ZeroExtend32(ccmd->y), ZeroExtend32(ccmd->width), ZeroExtend32(ccmd->height),
ccmd->color, ccmd->params);
}
break;
case GPUBackendCommandType::UpdateVRAM:
{
FlushRender();
const GPUBackendUpdateVRAMCommand* ccmd = static_cast<const GPUBackendUpdateVRAMCommand*>(cmd);
UpdateVRAM(ZeroExtend32(ccmd->x), ZeroExtend32(ccmd->y), ZeroExtend32(ccmd->width), ZeroExtend32(ccmd->height),
ccmd->data, ccmd->params);
}
break;
case GPUBackendCommandType::CopyVRAM:
{
FlushRender();
const GPUBackendCopyVRAMCommand* ccmd = static_cast<const GPUBackendCopyVRAMCommand*>(cmd);
CopyVRAM(ZeroExtend32(ccmd->src_x), ZeroExtend32(ccmd->src_y), ZeroExtend32(ccmd->dst_x),
ZeroExtend32(ccmd->dst_y), ZeroExtend32(ccmd->width), ZeroExtend32(ccmd->height), ccmd->params);
}
break;
case GPUBackendCommandType::SetDrawingArea:
{
FlushRender();
m_drawing_area = static_cast<const GPUBackendSetDrawingAreaCommand*>(cmd)->new_area;
DrawingAreaChanged();
}
break;
case GPUBackendCommandType::DrawPolygon:
{
DrawPolygon(static_cast<const GPUBackendDrawPolygonCommand*>(cmd));
}
break;
case GPUBackendCommandType::DrawRectangle:
{
DrawRectangle(static_cast<const GPUBackendDrawRectangleCommand*>(cmd));
}
break;
case GPUBackendCommandType::DrawLine:
{
DrawLine(static_cast<const GPUBackendDrawLineCommand*>(cmd));
}
break;
default:
break;
}
}