Duckstation/src/core/dma.h
2021-01-10 01:39:21 +10:00

205 lines
5.8 KiB
C++

#pragma once
#include "common/bitfield.h"
#include "types.h"
#include <array>
#include <memory>
#include <vector>
class StateWrapper;
class TimingEvent;
class DMA
{
public:
enum : u32
{
NUM_CHANNELS = 7
};
enum class Channel : u32
{
MDECin = 0,
MDECout = 1,
GPU = 2,
CDROM = 3,
SPU = 4,
PIO = 5,
OTC = 6
};
DMA();
~DMA();
void Initialize();
void Shutdown();
void Reset();
bool DoState(StateWrapper& sw);
u32 ReadRegister(u32 offset);
void WriteRegister(u32 offset, u32 value);
void SetRequest(Channel channel, bool request);
// changing interfaces
void SetMaxSliceTicks(TickCount ticks) { m_max_slice_ticks = ticks; }
void SetHaltTicks(TickCount ticks) { m_halt_ticks = ticks; }
void DrawDebugStateWindow();
private:
static constexpr PhysicalMemoryAddress BASE_ADDRESS_MASK = UINT32_C(0x00FFFFFF);
static constexpr PhysicalMemoryAddress ADDRESS_MASK = UINT32_C(0x001FFFFC);
enum class SyncMode : u32
{
Manual = 0,
Request = 1,
LinkedList = 2,
Reserved = 3
};
void ClearState();
// is everything enabled for a channel to operate?
bool CanTransferChannel(Channel channel, bool ignore_halt) const;
bool IsTransferHalted() const;
void UpdateIRQ();
// returns false if the DMA should now be halted
TickCount GetTransferSliceTicks() const;
TickCount GetTransferHaltTicks() const;
bool TransferChannel(Channel channel);
void HaltTransfer(TickCount duration);
void UnhaltTransfer(TickCount ticks);
// from device -> memory
TickCount TransferDeviceToMemory(Channel channel, u32 address, u32 increment, u32 word_count);
// from memory -> device
TickCount TransferMemoryToDevice(Channel channel, u32 address, u32 increment, u32 word_count);
// configuration
TickCount m_max_slice_ticks = 1000;
TickCount m_halt_ticks = 100;
std::vector<u32> m_transfer_buffer;
std::unique_ptr<TimingEvent> m_unhalt_event;
TickCount m_halt_ticks_remaining = 0;
struct ChannelState
{
u32 base_address = 0;
union BlockControl
{
u32 bits;
union
{
BitField<u32, u32, 0, 16> word_count;
u32 GetWordCount() const { return (word_count == 0) ? 0x10000 : word_count; }
} manual;
union
{
BitField<u32, u32, 0, 16> block_size;
BitField<u32, u32, 16, 16> block_count;
u32 GetBlockSize() const { return (block_size == 0) ? 0x10000 : block_size; }
u32 GetBlockCount() const { return (block_count == 0) ? 0x10000 : block_count; }
} request;
} block_control = {};
union ChannelControl
{
u32 bits;
BitField<u32, bool, 0, 1> copy_to_device;
BitField<u32, bool, 1, 1> address_step_reverse;
BitField<u32, bool, 8, 1> chopping_enable;
BitField<u32, SyncMode, 9, 2> sync_mode;
BitField<u32, u32, 16, 3> chopping_dma_window_size;
BitField<u32, u32, 20, 3> chopping_cpu_window_size;
BitField<u32, bool, 24, 1> enable_busy;
BitField<u32, bool, 28, 1> start_trigger;
static constexpr u32 WRITE_MASK = 0b01110001'01110111'00000111'00000011;
} channel_control = {};
bool request = false;
};
std::array<ChannelState, NUM_CHANNELS> m_state;
union DPCR
{
u32 bits;
BitField<u32, u8, 0, 3> MDECin_priority;
BitField<u32, bool, 3, 1> MDECin_master_enable;
BitField<u32, u8, 4, 3> MDECout_priority;
BitField<u32, bool, 7, 1> MDECout_master_enable;
BitField<u32, u8, 8, 3> GPU_priority;
BitField<u32, bool, 10, 1> GPU_master_enable;
BitField<u32, u8, 12, 3> CDROM_priority;
BitField<u32, bool, 15, 1> CDROM_master_enable;
BitField<u32, u8, 16, 3> SPU_priority;
BitField<u32, bool, 19, 1> SPU_master_enable;
BitField<u32, u8, 20, 3> PIO_priority;
BitField<u32, bool, 23, 1> PIO_master_enable;
BitField<u32, u8, 24, 3> OTC_priority;
BitField<u32, bool, 27, 1> OTC_master_enable;
BitField<u32, u8, 28, 3> priority_offset;
BitField<u32, bool, 31, 1> unused;
u8 GetPriority(Channel channel) const { return ((bits >> (static_cast<u8>(channel) * 4)) & u32(3)); }
bool GetMasterEnable(Channel channel) const
{
return ConvertToBoolUnchecked((bits >> (static_cast<u8>(channel) * 4 + 3)) & u32(1));
}
} m_DPCR = {};
static constexpr u32 DICR_WRITE_MASK = 0b00000000'11111111'10000000'00111111;
static constexpr u32 DICR_RESET_MASK = 0b01111111'00000000'00000000'00000000;
union DICR
{
u32 bits;
BitField<u32, bool, 15, 1> force_irq;
BitField<u32, bool, 16, 1> MDECin_irq_enable;
BitField<u32, bool, 17, 1> MDECout_irq_enable;
BitField<u32, bool, 18, 1> GPU_irq_enable;
BitField<u32, bool, 19, 1> CDROM_irq_enable;
BitField<u32, bool, 20, 1> SPU_irq_enable;
BitField<u32, bool, 21, 1> PIO_irq_enable;
BitField<u32, bool, 22, 1> OTC_irq_enable;
BitField<u32, bool, 23, 1> master_enable;
BitField<u32, bool, 24, 1> MDECin_irq_flag;
BitField<u32, bool, 25, 1> MDECout_irq_flag;
BitField<u32, bool, 26, 1> GPU_irq_flag;
BitField<u32, bool, 27, 1> CDROM_irq_flag;
BitField<u32, bool, 28, 1> SPU_irq_flag;
BitField<u32, bool, 29, 1> PIO_irq_flag;
BitField<u32, bool, 30, 1> OTC_irq_flag;
BitField<u32, bool, 31, 1> master_flag;
bool IsIRQEnabled(Channel channel) const
{
return ConvertToBoolUnchecked((bits >> (static_cast<u8>(channel) + 16)) & u32(1));
}
bool GetIRQFlag(Channel channel) const
{
return ConvertToBoolUnchecked((bits >> (static_cast<u8>(channel) + 24)) & u32(1));
}
void SetIRQFlag(Channel channel) { bits |= (u32(1) << (static_cast<u8>(channel) + 24)); }
void ClearIRQFlag(Channel channel) { bits &= ~(u32(1) << (static_cast<u8>(channel) + 24)); }
void UpdateMasterFlag()
{
master_flag = master_enable && ((((bits >> 16) & u32(0b1111111)) & ((bits >> 24) & u32(0b1111111))) != 0);
}
} m_DICR = {};
};
extern DMA g_dma;