Duckstation/src/core/mdec.h
Connor McLaughlin 7c7145d1c5 MDEC: Handle invalid commands
Fixes panic in Formula 1.
2020-12-19 02:44:46 +10:00

151 lines
3.6 KiB
C++

#pragma once
#include "common/bitfield.h"
#include "common/fifo_queue.h"
#include "types.h"
#include <array>
#include <memory>
class StateWrapper;
class TimingEvent;
class MDEC
{
public:
MDEC();
~MDEC();
void Initialize();
void Shutdown();
void Reset();
bool DoState(StateWrapper& sw);
// I/O
u32 ReadRegister(u32 offset);
void WriteRegister(u32 offset, u32 value);
void DMARead(u32* words, u32 word_count);
void DMAWrite(const u32* words, u32 word_count);
void DrawDebugStateWindow();
private:
static constexpr u32 DATA_IN_FIFO_SIZE = 1024;
static constexpr u32 DATA_OUT_FIFO_SIZE = 768;
static constexpr u32 NUM_BLOCKS = 6;
enum DataOutputDepth : u8
{
DataOutputDepth_4Bit = 0,
DataOutputDepth_8Bit = 1,
DataOutputDepth_24Bit = 2,
DataOutputDepth_15Bit = 3
};
enum class Command : u8
{
None = 0,
DecodeMacroblock = 1,
SetIqTab = 2,
SetScale = 3
};
enum class State : u8
{
Idle,
DecodingMacroblock,
WritingMacroblock,
SetIqTable,
SetScaleTable,
NoCommand
};
union StatusRegister
{
u32 bits;
BitField<u32, bool, 31, 1> data_out_fifo_empty;
BitField<u32, bool, 30, 1> data_in_fifo_full;
BitField<u32, bool, 29, 1> command_busy;
BitField<u32, bool, 28, 1> data_in_request;
BitField<u32, bool, 27, 1> data_out_request;
BitField<u32, DataOutputDepth, 25, 2> data_output_depth;
BitField<u32, bool, 24, 1> data_output_signed;
BitField<u32, u8, 23, 1> data_output_bit15;
BitField<u32, u8, 16, 3> current_block;
BitField<u32, u16, 0, 16> parameter_words_remaining;
};
union ControlRegister
{
u32 bits;
BitField<u32, bool, 31, 1> reset;
BitField<u32, bool, 30, 1> enable_dma_in;
BitField<u32, bool, 29, 1> enable_dma_out;
};
union CommandWord
{
u32 bits;
BitField<u32, Command, 29, 3> command;
BitField<u32, DataOutputDepth, 27, 2> data_output_depth;
BitField<u32, bool, 26, 1> data_output_signed;
BitField<u32, u8, 25, 1> data_output_bit15;
BitField<u32, u16, 0, 16> parameter_word_count;
};
bool HasPendingBlockCopyOut() const;
void SoftReset();
void ResetDecoder();
void UpdateStatus();
u32 ReadDataRegister();
void WriteCommandRegister(u32 value);
void Execute();
bool HandleDecodeMacroblockCommand();
void HandleSetQuantTableCommand();
void HandleSetScaleCommand();
bool DecodeMonoMacroblock();
bool DecodeColoredMacroblock();
void ScheduleBlockCopyOut(TickCount ticks);
void CopyOutBlock();
// from nocash spec
bool rl_decode_block(s16* blk, const u8* qt);
void IDCT(s16* blk);
void yuv_to_rgb(u32 xx, u32 yy, const std::array<s16, 64>& Crblk, const std::array<s16, 64>& Cbblk,
const std::array<s16, 64>& Yblk);
void y_to_mono(const std::array<s16, 64>& Yblk);
StatusRegister m_status = {};
bool m_enable_dma_in = false;
bool m_enable_dma_out = false;
// Even though the DMA is in words, we access the FIFO as halfwords.
InlineFIFOQueue<u16, DATA_IN_FIFO_SIZE / sizeof(u16)> m_data_in_fifo;
InlineFIFOQueue<u32, DATA_OUT_FIFO_SIZE / sizeof(u32)> m_data_out_fifo;
State m_state = State::Idle;
u32 m_remaining_halfwords = 0;
std::array<u8, 64> m_iq_uv{};
std::array<u8, 64> m_iq_y{};
std::array<s16, 64> m_scale_table{};
// blocks, for colour: 0 - Crblk, 1 - Cbblk, 2-5 - Y 1-4
std::array<std::array<s16, 64>, NUM_BLOCKS> m_blocks;
u32 m_current_block = 0; // block (0-5)
u32 m_current_coefficient = 64; // k (in block)
u16 m_current_q_scale = 0;
std::array<u32, 256> m_block_rgb{};
std::unique_ptr<TimingEvent> m_block_copy_out_event;
u32 m_total_blocks_decoded = 0;
};
extern MDEC g_mdec;