GB MBC: Support for unlicensed Pokemon Jade/Diamond Game Boy mapper

CHANGES

@@ -2,6 +2,7 @@
 Features:
  - e-Reader card scanning
  - Add APNG recording
+ - Support for unlicensed Pokemon Jade/Diamond Game Boy mapper
 Emulation fixes:
  - ARM: Fix ALU reading PC after shifting
  - ARM: Fix STR storing PC after address calculation

README.md

@@ -51,6 +51,7 @@ The following mappers are fully supported:
 - MBC5+Rumble
 - MBC7
 - Wisdom Tree (unlicensed)
+- Pokémon Jade/Diamond (unlicensed)
 
 The following mappers are partially supported:
 

include/mgba/gb/interface.h

@@ -34,9 +34,10 @@ enum GBMemoryBankControllerType {
 	GB_HuC3 = 0x12,
 	GB_POCKETCAM = 0x13,
 	GB_TAMA5 = 0x14,
-	GB_UNL_WISDOM_TREE = 0x20,
 	GB_MBC3_RTC = 0x103,
-	GB_MBC5_RUMBLE = 0x105
+	GB_MBC5_RUMBLE = 0x105,
+	GB_UNL_WISDOM_TREE = 0x200,
+	GB_UNL_PKJD = 0x203,
 };
 
 struct GBSIODriver {

include/mgba/internal/gb/memory.h

@@ -146,6 +146,10 @@ struct GBTAMA5State {
 	uint8_t registers[GBTAMA5_MAX];
 };
 
+struct GBPKJDState {
+	uint8_t reg[2];
+};
+
 union GBMBCState {
 	struct GBMBC1State mbc1;
 	struct GBMBC6State mbc6;
@@ -153,6 +157,7 @@ union GBMBCState {
 	struct GBMMM01State mmm01;
 	struct GBPocketCamState pocketCam;
 	struct GBTAMA5State tama5;
+	struct GBPKJDState pkjd;
 };
 
 struct mRotationSource;
@@ -171,6 +176,7 @@ struct GBMemory {
 	int wramCurrentBank;
 
 	bool sramAccess;
+	bool directSramAccess;
 	uint8_t* sram;
 	uint8_t* sramBank;
 	int sramCurrentBank;

src/core/core.c

@@ -162,6 +162,10 @@ bool mCorePreloadVFCB(struct mCore* core, struct VFile* vf, void (cb)(size_t, si
 		}
 	}
 	vf->close(vf);
+	if (read < 0) {
+		vfm->close(vfm);
+		return false;
+	}
 	bool ret = core->loadROM(core, vfm);
 	if (!ret) {
 		vfm->close(vfm);

src/gb/mbc.c

@@ -36,6 +36,7 @@ static void _GBHuC3(struct GB*, uint16_t address, uint8_t value);
 static void _GBPocketCam(struct GB* gb, uint16_t address, uint8_t value);
 static void _GBTAMA5(struct GB* gb, uint16_t address, uint8_t value);
 static void _GBWisdomTree(struct GB* gb, uint16_t address, uint8_t value);
+static void _GBPKJD(struct GB* gb, uint16_t address, uint8_t value);
 
 static uint8_t _GBMBC2Read(struct GBMemory*, uint16_t address);
 static uint8_t _GBMBC6Read(struct GBMemory*, uint16_t address);
@@ -43,6 +44,7 @@ static uint8_t _GBMBC7Read(struct GBMemory*, uint16_t address);
 static void _GBMBC7Write(struct GBMemory* memory, uint16_t address, uint8_t value);
 
 static uint8_t _GBTAMA5Read(struct GBMemory*, uint16_t address);
+static uint8_t _GBPKJDRead(struct GBMemory*, uint16_t address);
 
 static uint8_t _GBPocketCamRead(struct GBMemory*, uint16_t address);
 static void _GBPocketCamCapture(struct GBMemory*);
@@ -273,6 +275,7 @@ void GBMBCInit(struct GB* gb) {
 		gb->memory.mbcType = GB_MBC_NONE;
 	}
 	gb->memory.mbcRead = NULL;
+	gb->memory.directSramAccess = true;
 	switch (gb->memory.mbcType) {
 	case GB_MBC_NONE:
 		gb->memory.mbcWrite = _GBMBCNone;
@@ -288,6 +291,7 @@ void GBMBCInit(struct GB* gb) {
 	case GB_MBC2:
 		gb->memory.mbcWrite = _GBMBC2;
 		gb->memory.mbcRead = _GBMBC2Read;
+		gb->memory.directSramAccess = false;
 		gb->sramSize = 0x100;
 		break;
 	case GB_MBC3:
@@ -300,9 +304,9 @@ void GBMBCInit(struct GB* gb) {
 		gb->memory.mbcWrite = _GBMBC5;
 		break;
 	case GB_MBC6:
-		mLOG(GB_MBC, WARN, "unimplemented MBC: MBC6");
 		gb->memory.mbcWrite = _GBMBC6;
 		gb->memory.mbcRead = _GBMBC6Read;
+		gb->memory.directSramAccess = false;
 		break;
 	case GB_MBC7:
 		gb->memory.mbcWrite = _GBMBC7;
@@ -342,6 +346,10 @@ void GBMBCInit(struct GB* gb) {
 	case GB_UNL_WISDOM_TREE:
 		gb->memory.mbcWrite = _GBWisdomTree;
 		break;
+	case GB_UNL_PKJD:
+		gb->memory.mbcWrite = _GBPKJD;
+		gb->memory.mbcRead = _GBPKJDRead;
+		break;
 	}
 
 	gb->memory.currentBank = 1;
@@ -626,10 +634,10 @@ void _GBMBC6(struct GB* gb, uint16_t address, uint8_t value) {
 	case 0:
 		switch (value) {
 		case 0:
-			memory->mbcState.mbc6.sramAccess = false;
+			memory->sramAccess = false;
 			break;
 		case 0xA:
-			memory->mbcState.mbc6.sramAccess = true;
+			memory->sramAccess = true;
 			break;
 		default:
 			// TODO
@@ -655,7 +663,7 @@ void _GBMBC6(struct GB* gb, uint16_t address, uint8_t value) {
 	case 0x29:
 	case 0x2A:
 	case 0x2B:
-		if (memory->mbcState.mbc6.sramAccess) {
+		if (memory->sramAccess) {
 			memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM_HALFBANK - 1)] = value;
 		}
 		break;
@@ -663,7 +671,7 @@ void _GBMBC6(struct GB* gb, uint16_t address, uint8_t value) {
 	case 0x2D:
 	case 0x2E:
 	case 0x2F:
-		if (memory->mbcState.mbc6.sramAccess) {
+		if (memory->sramAccess) {
 			memory->mbcState.mbc6.sramBank1[address & (GB_SIZE_EXTERNAL_RAM_HALFBANK - 1)] = value;
 		}
 		break;
@@ -674,7 +682,7 @@ void _GBMBC6(struct GB* gb, uint16_t address, uint8_t value) {
 }
 
 uint8_t _GBMBC6Read(struct GBMemory* memory, uint16_t address) {
-	if (!memory->mbcState.mbc6.sramAccess) {
+	if (!memory->sramAccess) {
 		return 0xFF;
 	}
 	switch (address >> 12) {
@@ -1229,6 +1237,74 @@ void _GBWisdomTree(struct GB* gb, uint16_t address, uint8_t value) {
 	}
 }
 
+void _GBPKJD(struct GB* gb, uint16_t address, uint8_t value) {
+	struct GBMemory* memory = &gb->memory;
+	switch (address >> 13) {
+	case 0x2:
+		if (value < 8) {
+			memory->directSramAccess = true;
+			memory->activeRtcReg = 0;
+		} else if (value >= 0xD && value <= 0xF) {
+			memory->directSramAccess = false;
+			memory->rtcAccess = false;
+			memory->activeRtcReg = value - 8;
+		}
+		break;
+	case 0x5:
+		if (!memory->sramAccess) {
+			return;
+		}
+		switch (memory->activeRtcReg) {
+		case 0:
+			memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)] = value;
+			break;
+		case 5:
+		case 6:
+			memory->mbcState.pkjd.reg[memory->activeRtcReg - 5] = value;
+			break;
+		case 7:
+			switch (value) {
+			case 0x11:
+				memory->mbcState.pkjd.reg[0]--;
+				break;
+			case 0x12:
+				memory->mbcState.pkjd.reg[1]--;
+				break;
+			case 0x41:
+				memory->mbcState.pkjd.reg[0] += memory->mbcState.pkjd.reg[1];
+				break;
+			case 0x42:
+				memory->mbcState.pkjd.reg[1] += memory->mbcState.pkjd.reg[0];
+				break;
+			case 0x51:
+				memory->mbcState.pkjd.reg[0]++;
+				break;
+			case 0x52:
+				memory->mbcState.pkjd.reg[1]--;
+				break;
+			}
+			break;
+		}
+		return;
+	}
+	_GBMBC3(gb, address, value);
+}
+
+static uint8_t _GBPKJDRead(struct GBMemory* memory, uint16_t address) {
+	if (!memory->sramAccess) {
+		return 0xFF;
+	}
+	switch (memory->activeRtcReg) {
+	case 0:
+		return memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)];
+	case 5:
+	case 6:
+		return memory->mbcState.pkjd.reg[memory->activeRtcReg - 5];
+	default:
+		return 0;
+	}
+}
+
 void GBMBCRTCRead(struct GB* gb) {
 	struct GBMBCRTCSaveBuffer rtcBuffer;
 	struct VFile* vf = gb->sramVf;

src/gb/memory.c

@@ -361,7 +361,7 @@ void GBStore8(struct SM83Core* cpu, uint16_t address, int8_t value) {
 	case GB_REGION_EXTERNAL_RAM + 1:
 		if (memory->rtcAccess) {
 			memory->rtcRegs[memory->activeRtcReg] = value;
-		} else if (memory->sramAccess && memory->sram && memory->mbcType != GB_MBC2) {
+		} else if (memory->sramAccess && memory->sram && memory->directSramAccess) {
 			memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)] = value;
 		} else {
 			memory->mbcWrite(gb, address, value);

src/gb/overrides.c

@@ -495,6 +495,7 @@ static const struct GBCartridgeOverride _overrides[] = {
 	{ 0x630ed957, GB_MODEL_AUTODETECT, GB_MBC3_RTC, { 0 } }, // Gold (non-debug)
 	{ 0x5aff0038, GB_MODEL_AUTODETECT, GB_MBC3_RTC, { 0 } }, // Silver (debug)
 	{ 0xa61856bd, GB_MODEL_AUTODETECT, GB_MBC3_RTC, { 0 } }, // Silver (non-debug)
+	{ 0x30f8f86c, GB_MODEL_AUTODETECT, GB_UNL_PKJD, { 0 } }, // Pokemon Jade Version (Telefang Speed bootleg)
 
 	{ 0, 0, 0, { 0 } }
 };

src/platform/qt/OverrideView.cpp

@@ -50,6 +50,7 @@ OverrideView::OverrideView(ConfigController* config, QWidget* parent)
 		s_mbcList.append(GB_HuC1);
 		s_mbcList.append(GB_HuC3);
 		s_mbcList.append(GB_UNL_WISDOM_TREE);
+		s_mbcList.append(GB_UNL_PKJD);
 	}
 	if (s_gbModelList.isEmpty()) {
 		// NB: Keep in sync with OverrideView.ui

src/platform/qt/OverrideView.ui

@@ -359,6 +359,11 @@
            <string>Wisdom Tree (Unlicensed)</string>
           </property>
          </item>
+         <item>
+          <property name="text">
+           <string>Pokémon Jade/Diamond (Unlicensed)</string>
+          </property>
+         </item>
         </widget>
        </item>
        <item row="2" column="0">