mgba-ps3/src/gb/mbc.c

731 lines
17 KiB
C

/* Copyright (c) 2013-2016 Jeffrey Pfau
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include <mgba/internal/gb/mbc.h>
#include <mgba/core/interface.h>
#include <mgba/internal/lr35902/lr35902.h>
#include <mgba/internal/gb/gb.h>
#include <mgba/internal/gb/memory.h>
#include <mgba-util/vfs.h>
mLOG_DEFINE_CATEGORY(GB_MBC, "GB MBC", "gb.mbc");
static void _GBMBCNone(struct GB* gb, uint16_t address, uint8_t value) {
UNUSED(gb);
UNUSED(address);
UNUSED(value);
mLOG(GB_MBC, GAME_ERROR, "Wrote to invalid MBC");
}
static void _GBMBC1(struct GB*, uint16_t address, uint8_t value);
static void _GBMBC2(struct GB*, uint16_t address, uint8_t value);
static void _GBMBC3(struct GB*, uint16_t address, uint8_t value);
static void _GBMBC5(struct GB*, uint16_t address, uint8_t value);
static void _GBMBC6(struct GB*, uint16_t address, uint8_t value);
static void _GBMBC7(struct GB*, uint16_t address, uint8_t value);
static void _GBHuC3(struct GB*, uint16_t address, uint8_t value);
void GBMBCSwitchBank(struct GB* gb, int bank) {
size_t bankStart = bank * GB_SIZE_CART_BANK0;
if (bankStart + GB_SIZE_CART_BANK0 > gb->memory.romSize) {
mLOG(GB_MBC, GAME_ERROR, "Attempting to switch to an invalid ROM bank: %0X", bank);
bankStart &= (gb->memory.romSize - 1);
bank = bankStart / GB_SIZE_CART_BANK0;
if (!bank) {
++bank;
}
}
gb->memory.romBank = &gb->memory.rom[bankStart];
gb->memory.currentBank = bank;
if (gb->cpu->pc < GB_BASE_VRAM) {
gb->cpu->memory.setActiveRegion(gb->cpu, gb->cpu->pc);
}
}
static void _switchBank0(struct GB* gb, int bank) {
size_t bankStart = bank * GB_SIZE_CART_BANK0 << gb->memory.mbcState.mbc1.multicartStride;
if (bankStart + GB_SIZE_CART_BANK0 > gb->memory.romSize) {
mLOG(GB_MBC, GAME_ERROR, "Attempting to switch to an invalid ROM bank: %0X", bank);
bankStart &= (gb->memory.romSize - 1);
}
gb->memory.romBase = &gb->memory.rom[bankStart];
if (gb->cpu->pc < GB_SIZE_CART_BANK0) {
gb->cpu->memory.setActiveRegion(gb->cpu, gb->cpu->pc);
}
}
static bool _isMulticart(const uint8_t* mem) {
bool success = true;
struct VFile* vf;
vf = VFileFromConstMemory(&mem[GB_SIZE_CART_BANK0 * 0x10], 1024);
success = success && GBIsROM(vf);
vf->close(vf);
vf = VFileFromConstMemory(&mem[GB_SIZE_CART_BANK0 * 0x20], 1024);
success = success && GBIsROM(vf);
vf->close(vf);
return success;
}
void GBMBCSwitchSramBank(struct GB* gb, int bank) {
size_t bankStart = bank * GB_SIZE_EXTERNAL_RAM;
GBResizeSram(gb, (bank + 1) * GB_SIZE_EXTERNAL_RAM);
gb->memory.sramBank = &gb->memory.sram[bankStart];
gb->memory.sramCurrentBank = bank;
}
void GBMBCInit(struct GB* gb) {
const struct GBCartridge* cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
if (gb->memory.rom) {
switch (cart->ramSize) {
case 0:
gb->sramSize = 0;
break;
case 1:
gb->sramSize = 0x800;
break;
default:
case 2:
gb->sramSize = 0x2000;
break;
case 3:
gb->sramSize = 0x8000;
break;
}
if (gb->memory.mbcType == GB_MBC_AUTODETECT) {
switch (cart->type) {
case 0:
case 8:
case 9:
gb->memory.mbcType = GB_MBC_NONE;
break;
case 1:
case 2:
case 3:
gb->memory.mbcType = GB_MBC1;
if (gb->memory.romSize >= GB_SIZE_CART_BANK0 * 0x31 && _isMulticart(gb->memory.rom)) {
gb->memory.mbcState.mbc1.multicartStride = 4;
} else {
gb->memory.mbcState.mbc1.multicartStride = 5;
}
break;
case 5:
case 6:
gb->memory.mbcType = GB_MBC2;
break;
case 0x0F:
case 0x10:
gb->memory.mbcType = GB_MBC3_RTC;
break;
case 0x11:
case 0x12:
case 0x13:
gb->memory.mbcType = GB_MBC3;
break;
default:
mLOG(GB_MBC, WARN, "Unknown MBC type: %02X", cart->type);
// Fall through
case 0x19:
case 0x1A:
case 0x1B:
gb->memory.mbcType = GB_MBC5;
break;
case 0x1C:
case 0x1D:
case 0x1E:
gb->memory.mbcType = GB_MBC5_RUMBLE;
break;
case 0x20:
gb->memory.mbcType = GB_MBC6;
break;
case 0x22:
gb->memory.mbcType = GB_MBC7;
break;
case 0xFE:
gb->memory.mbcType = GB_HuC3;
break;
}
}
} else {
gb->memory.mbcType = GB_MBC_NONE;
}
switch (gb->memory.mbcType) {
case GB_MBC_NONE:
gb->memory.mbc = _GBMBCNone;
break;
case GB_MBC1:
gb->memory.mbc = _GBMBC1;
break;
case GB_MBC2:
gb->memory.mbc = _GBMBC2;
gb->sramSize = 0x200;
break;
case GB_MBC3:
gb->memory.mbc = _GBMBC3;
break;
default:
mLOG(GB_MBC, WARN, "Unknown MBC type: %02X", cart->type);
// Fall through
case GB_MBC5:
gb->memory.mbc = _GBMBC5;
break;
case GB_MBC6:
mLOG(GB_MBC, WARN, "unimplemented MBC: MBC6");
gb->memory.mbc = _GBMBC6;
break;
case GB_MBC7:
gb->memory.mbc = _GBMBC7;
gb->sramSize = GB_SIZE_EXTERNAL_RAM;
break;
case GB_MMM01:
mLOG(GB_MBC, WARN, "unimplemented MBC: MMM01");
gb->memory.mbc = _GBMBC1;
break;
case GB_HuC1:
mLOG(GB_MBC, WARN, "unimplemented MBC: HuC-1");
gb->memory.mbc = _GBMBC1;
break;
case GB_HuC3:
gb->memory.mbc = _GBHuC3;
break;
case GB_MBC3_RTC:
memset(gb->memory.rtcRegs, 0, sizeof(gb->memory.rtcRegs));
gb->memory.mbc = _GBMBC3;
break;
case GB_MBC5_RUMBLE:
gb->memory.mbc = _GBMBC5;
break;
}
GBResizeSram(gb, gb->sramSize);
if (gb->memory.mbcType == GB_MBC3_RTC) {
GBMBCRTCRead(gb);
}
}
static void _latchRtc(struct mRTCSource* rtc, uint8_t* rtcRegs, time_t* rtcLastLatch) {
time_t t;
if (rtc) {
if (rtc->sample) {
rtc->sample(rtc);
}
t = rtc->unixTime(rtc);
} else {
t = time(0);
}
time_t currentLatch = t;
t -= *rtcLastLatch;
*rtcLastLatch = currentLatch;
int64_t diff;
diff = rtcRegs[0] + t % 60;
if (diff < 0) {
diff += 60;
t -= 60;
}
rtcRegs[0] = diff % 60;
t /= 60;
t += diff / 60;
diff = rtcRegs[1] + t % 60;
if (diff < 0) {
diff += 60;
t -= 60;
}
rtcRegs[1] = diff % 60;
t /= 60;
t += diff / 60;
diff = rtcRegs[2] + t % 24;
if (diff < 0) {
diff += 24;
t -= 24;
}
rtcRegs[2] = diff % 24;
t /= 24;
t += diff / 24;
diff = rtcRegs[3] + ((rtcRegs[4] & 1) << 8) + (t & 0x1FF);
rtcRegs[3] = diff;
rtcRegs[4] &= 0xFE;
rtcRegs[4] |= (diff >> 8) & 1;
if (diff & 0x200) {
rtcRegs[4] |= 0x80;
}
}
void _GBMBC1(struct GB* gb, uint16_t address, uint8_t value) {
struct GBMemory* memory = &gb->memory;
int bank = value & 0x1F;
int stride = 1 << memory->mbcState.mbc1.multicartStride;
switch (address >> 13) {
case 0x0:
switch (value) {
case 0:
memory->sramAccess = false;
break;
case 0xA:
memory->sramAccess = true;
GBMBCSwitchSramBank(gb, memory->sramCurrentBank);
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC1 unknown value %02X", value);
break;
}
break;
case 0x1:
if (!bank) {
++bank;
}
bank &= stride - 1;
GBMBCSwitchBank(gb, bank | (memory->currentBank & (3 * stride)));
break;
case 0x2:
bank &= 3;
if (memory->mbcState.mbc1.mode) {
_switchBank0(gb, bank);
GBMBCSwitchSramBank(gb, bank);
}
GBMBCSwitchBank(gb, (bank << memory->mbcState.mbc1.multicartStride) | (memory->currentBank & (stride - 1)));
break;
case 0x3:
memory->mbcState.mbc1.mode = value & 1;
if (memory->mbcState.mbc1.mode) {
_switchBank0(gb, memory->currentBank >> memory->mbcState.mbc1.multicartStride);
} else {
_switchBank0(gb, 0);
GBMBCSwitchSramBank(gb, 0);
}
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC1 unknown address: %04X:%02X", address, value);
break;
}
}
void _GBMBC2(struct GB* gb, uint16_t address, uint8_t value) {
struct GBMemory* memory = &gb->memory;
int bank = value & 0xF;
switch (address >> 13) {
case 0x0:
switch (value) {
case 0:
memory->sramAccess = false;
break;
case 0xA:
memory->sramAccess = true;
GBMBCSwitchSramBank(gb, memory->sramCurrentBank);
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC1 unknown value %02X", value);
break;
}
break;
case 0x1:
if (!bank) {
++bank;
}
GBMBCSwitchBank(gb, bank);
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC2 unknown address: %04X:%02X", address, value);
break;
}}
void _GBMBC3(struct GB* gb, uint16_t address, uint8_t value) {
struct GBMemory* memory = &gb->memory;
int bank = value & 0x7F;
switch (address >> 13) {
case 0x0:
switch (value) {
case 0:
memory->sramAccess = false;
break;
case 0xA:
memory->sramAccess = true;
GBMBCSwitchSramBank(gb, memory->sramCurrentBank);
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC3 unknown value %02X", value);
break;
}
break;
case 0x1:
if (!bank) {
++bank;
}
GBMBCSwitchBank(gb, bank);
break;
case 0x2:
if (value < 4) {
GBMBCSwitchSramBank(gb, value);
memory->rtcAccess = false;
} else if (value >= 8 && value <= 0xC) {
memory->activeRtcReg = value - 8;
memory->rtcAccess = true;
}
break;
case 0x3:
if (memory->rtcLatched && value == 0) {
memory->rtcLatched = false;
} else if (!memory->rtcLatched && value == 1) {
_latchRtc(gb->memory.rtc, gb->memory.rtcRegs, &gb->memory.rtcLastLatch);
memory->rtcLatched = true;
}
break;
}
}
void _GBMBC5(struct GB* gb, uint16_t address, uint8_t value) {
struct GBMemory* memory = &gb->memory;
int bank;
switch (address >> 12) {
case 0x0:
case 0x1:
switch (value) {
case 0:
memory->sramAccess = false;
break;
case 0xA:
memory->sramAccess = true;
GBMBCSwitchSramBank(gb, memory->sramCurrentBank);
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC5 unknown value %02X", value);
break;
}
break;
case 0x2:
bank = (memory->currentBank & 0x100) | value;
GBMBCSwitchBank(gb, bank);
break;
case 0x3:
bank = (memory->currentBank & 0xFF) | ((value & 1) << 8);
GBMBCSwitchBank(gb, bank);
break;
case 0x4:
case 0x5:
if (memory->mbcType == GB_MBC5_RUMBLE && memory->rumble) {
memory->rumble->setRumble(memory->rumble, (value >> 3) & 1);
value &= ~8;
}
GBMBCSwitchSramBank(gb, value & 0xF);
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC5 unknown address: %04X:%02X", address, value);
break;
}
}
void _GBMBC6(struct GB* gb, uint16_t address, uint8_t value) {
// TODO
mLOG(GB_MBC, STUB, "MBC6 unimplemented");
UNUSED(gb);
UNUSED(address);
UNUSED(value);
}
void _GBMBC7(struct GB* gb, uint16_t address, uint8_t value) {
int bank = value & 0x7F;
switch (address >> 13) {
case 0x1:
GBMBCSwitchBank(gb, bank);
break;
case 0x2:
if (value < 0x10) {
GBMBCSwitchSramBank(gb, value);
}
break;
default:
// TODO
mLOG(GB_MBC, STUB, "MBC7 unknown address: %04X:%02X", address, value);
break;
}
}
uint8_t GBMBC7Read(struct GBMemory* memory, uint16_t address) {
struct GBMBC7State* mbc7 = &memory->mbcState.mbc7;
switch (address & 0xF0) {
case 0x00:
case 0x10:
case 0x60:
case 0x70:
return 0;
case 0x20:
if (memory->rotation && memory->rotation->readTiltX) {
int32_t x = -memory->rotation->readTiltX(memory->rotation);
x >>= 21;
x += 2047;
return x;
}
return 0xFF;
case 0x30:
if (memory->rotation && memory->rotation->readTiltX) {
int32_t x = -memory->rotation->readTiltX(memory->rotation);
x >>= 21;
x += 2047;
return x >> 8;
}
return 7;
case 0x40:
if (memory->rotation && memory->rotation->readTiltY) {
int32_t y = -memory->rotation->readTiltY(memory->rotation);
y >>= 21;
y += 2047;
return y;
}
return 0xFF;
case 0x50:
if (memory->rotation && memory->rotation->readTiltY) {
int32_t y = -memory->rotation->readTiltY(memory->rotation);
y >>= 21;
y += 2047;
return y >> 8;
}
return 7;
case 0x80:
return (mbc7->sr >> 16) & 1;
default:
return 0xFF;
}
}
void GBMBC7Write(struct GBMemory* memory, uint16_t address, uint8_t value) {
if ((address & 0xF0) != 0x80) {
return;
}
struct GBMBC7State* mbc7 = &memory->mbcState.mbc7;
GBMBC7Field old = memory->mbcState.mbc7.field;
mbc7->field = GBMBC7FieldClearIO(value);
if (!GBMBC7FieldIsCS(old) && GBMBC7FieldIsCS(value)) {
if (mbc7->state == GBMBC7_STATE_WRITE) {
if (mbc7->writable) {
memory->sramBank[mbc7->address * 2] = mbc7->sr >> 8;
memory->sramBank[mbc7->address * 2 + 1] = mbc7->sr;
}
mbc7->sr = 0x1FFFF;
mbc7->state = GBMBC7_STATE_NULL;
} else {
mbc7->state = GBMBC7_STATE_IDLE;
}
}
if (!GBMBC7FieldIsSK(old) && GBMBC7FieldIsSK(value)) {
if (mbc7->state > GBMBC7_STATE_IDLE && mbc7->state != GBMBC7_STATE_READ) {
mbc7->sr <<= 1;
mbc7->sr |= GBMBC7FieldGetIO(value);
++mbc7->srBits;
}
switch (mbc7->state) {
case GBMBC7_STATE_IDLE:
if (GBMBC7FieldIsIO(value)) {
mbc7->state = GBMBC7_STATE_READ_COMMAND;
mbc7->srBits = 0;
mbc7->sr = 0;
}
break;
case GBMBC7_STATE_READ_COMMAND:
if (mbc7->srBits == 2) {
mbc7->state = GBMBC7_STATE_READ_ADDRESS;
mbc7->srBits = 0;
mbc7->command = mbc7->sr;
}
break;
case GBMBC7_STATE_READ_ADDRESS:
if (mbc7->srBits == 8) {
mbc7->state = GBMBC7_STATE_COMMAND_0 + mbc7->command;
mbc7->srBits = 0;
mbc7->address = mbc7->sr;
if (mbc7->state == GBMBC7_STATE_COMMAND_0) {
switch (mbc7->address >> 6) {
case 0:
mbc7->writable = false;
mbc7->state = GBMBC7_STATE_NULL;
break;
case 3:
mbc7->writable = true;
mbc7->state = GBMBC7_STATE_NULL;
break;
}
}
}
break;
case GBMBC7_STATE_COMMAND_0:
if (mbc7->srBits == 16) {
switch (mbc7->address >> 6) {
case 0:
mbc7->writable = false;
mbc7->state = GBMBC7_STATE_NULL;
break;
case 1:
mbc7->state = GBMBC7_STATE_WRITE;
if (mbc7->writable) {
int i;
for (i = 0; i < 256; ++i) {
memory->sramBank[i * 2] = mbc7->sr >> 8;
memory->sramBank[i * 2 + 1] = mbc7->sr;
}
}
break;
case 2:
mbc7->state = GBMBC7_STATE_WRITE;
if (mbc7->writable) {
int i;
for (i = 0; i < 256; ++i) {
memory->sramBank[i * 2] = 0xFF;
memory->sramBank[i * 2 + 1] = 0xFF;
}
}
break;
case 3:
mbc7->writable = true;
mbc7->state = GBMBC7_STATE_NULL;
break;
}
}
break;
case GBMBC7_STATE_COMMAND_SR_WRITE:
if (mbc7->srBits == 16) {
mbc7->srBits = 0;
mbc7->state = GBMBC7_STATE_WRITE;
}
break;
case GBMBC7_STATE_COMMAND_SR_READ:
if (mbc7->srBits == 1) {
mbc7->sr = memory->sramBank[mbc7->address * 2] << 8;
mbc7->sr |= memory->sramBank[mbc7->address * 2 + 1];
mbc7->srBits = 0;
mbc7->state = GBMBC7_STATE_READ;
}
break;
case GBMBC7_STATE_COMMAND_SR_FILL:
if (mbc7->srBits == 16) {
mbc7->sr = 0xFFFF;
mbc7->srBits = 0;
mbc7->state = GBMBC7_STATE_WRITE;
}
break;
default:
break;
}
} else if (GBMBC7FieldIsSK(old) && !GBMBC7FieldIsSK(value)) {
if (mbc7->state == GBMBC7_STATE_READ) {
mbc7->sr <<= 1;
++mbc7->srBits;
if (mbc7->srBits == 16) {
mbc7->srBits = 0;
mbc7->state = GBMBC7_STATE_NULL;
}
}
}
}
void _GBHuC3(struct GB* gb, uint16_t address, uint8_t value) {
struct GBMemory* memory = &gb->memory;
int bank = value & 0x3F;
if (address & 0x1FFF) {
mLOG(GB_MBC, STUB, "HuC-3 unknown value %04X:%02X", address, value);
}
switch (address >> 13) {
case 0x0:
switch (value) {
case 0xA:
memory->sramAccess = true;
GBMBCSwitchSramBank(gb, memory->sramCurrentBank);
break;
default:
memory->sramAccess = false;
break;
}
break;
case 0x1:
GBMBCSwitchBank(gb, bank);
break;
case 0x2:
GBMBCSwitchSramBank(gb, bank);
break;
default:
// TODO
mLOG(GB_MBC, STUB, "HuC-3 unknown address: %04X:%02X", address, value);
break;
}
}
void GBMBCRTCRead(struct GB* gb) {
struct GBMBCRTCSaveBuffer rtcBuffer;
struct VFile* vf = gb->sramVf;
if (!vf) {
return;
}
ssize_t end = vf->seek(vf, -sizeof(rtcBuffer), SEEK_END);
switch (end & 0x1FFF) {
case 0:
break;
case 0x1FFC:
vf->seek(vf, -sizeof(rtcBuffer) - 4, SEEK_END);
break;
default:
return;
}
vf->read(vf, &rtcBuffer, sizeof(rtcBuffer));
LOAD_32LE(gb->memory.rtcRegs[0], 0, &rtcBuffer.latchedSec);
LOAD_32LE(gb->memory.rtcRegs[1], 0, &rtcBuffer.latchedMin);
LOAD_32LE(gb->memory.rtcRegs[2], 0, &rtcBuffer.latchedHour);
LOAD_32LE(gb->memory.rtcRegs[3], 0, &rtcBuffer.latchedDays);
LOAD_32LE(gb->memory.rtcRegs[4], 0, &rtcBuffer.latchedDaysHi);
LOAD_64LE(gb->memory.rtcLastLatch, 0, &rtcBuffer.unixTime);
}
void GBMBCRTCWrite(struct GB* gb) {
struct VFile* vf = gb->sramVf;
if (!vf) {
return;
}
uint8_t rtcRegs[5];
memcpy(rtcRegs, gb->memory.rtcRegs, sizeof(rtcRegs));
time_t rtcLastLatch = gb->memory.rtcLastLatch;
_latchRtc(gb->memory.rtc, rtcRegs, &rtcLastLatch);
struct GBMBCRTCSaveBuffer rtcBuffer;
STORE_32LE(rtcRegs[0], 0, &rtcBuffer.sec);
STORE_32LE(rtcRegs[1], 0, &rtcBuffer.min);
STORE_32LE(rtcRegs[2], 0, &rtcBuffer.hour);
STORE_32LE(rtcRegs[3], 0, &rtcBuffer.days);
STORE_32LE(rtcRegs[4], 0, &rtcBuffer.daysHi);
STORE_32LE(gb->memory.rtcRegs[0], 0, &rtcBuffer.latchedSec);
STORE_32LE(gb->memory.rtcRegs[1], 0, &rtcBuffer.latchedMin);
STORE_32LE(gb->memory.rtcRegs[2], 0, &rtcBuffer.latchedHour);
STORE_32LE(gb->memory.rtcRegs[3], 0, &rtcBuffer.latchedDays);
STORE_32LE(gb->memory.rtcRegs[4], 0, &rtcBuffer.latchedDaysHi);
STORE_64LE(rtcLastLatch, 0, &rtcBuffer.unixTime);
if (vf->size(vf) == gb->sramSize) {
// Writing past the end of the file can invalidate the file mapping
vf->unmap(vf, gb->memory.sram, gb->sramSize);
gb->memory.sram = NULL;
}
vf->seek(vf, gb->sramSize, SEEK_SET);
vf->write(vf, &rtcBuffer, sizeof(rtcBuffer));
if (!gb->memory.sram) {
gb->memory.sram = vf->map(vf, gb->sramSize, MAP_WRITE);
GBMBCSwitchSramBank(gb, gb->memory.sramCurrentBank);
}
}