GB MBC: Add GGB-81 support

CHANGES

@@ -1,6 +1,6 @@
 0.11.0: (Future)
 Features:
- - New unlicensed GB mappers: NT (older types 1 and 2), Li Cheng
+ - New unlicensed GB mappers: NT (older types 1 and 2), Li Cheng, GGB-81
  - Debugger: Add range watchpoints
 Other fixes:
  - Qt: Manually split filename to avoid overzealous splitting (fixes mgba.io/i/2681)

README.md

@@ -71,6 +71,7 @@ The following mappers are partially supported:
 - Sachen MMC2 (missing alternate wiring support)
 - BBD (missing logo switching)
 - Hitek (missing logo switching)
+- GGB-81 (missing logo switching)
 - Li Cheng (missing logo switching)
 
 ### Planned features

include/mgba/gb/interface.h

@@ -47,6 +47,7 @@ enum GBMemoryBankControllerType {
 	GB_UNL_BBD = 0x220,
 	GB_UNL_HITEK = 0x221,
 	GB_UNL_LI_CHENG = 0x222,
+	GB_UNL_GGB81 = 0x223,
 	GB_UNL_SACHEN_MMC1 = 0x230,
 	GB_UNL_SACHEN_MMC2 = 0x231,
 };

src/gb/mbc.c

@@ -126,7 +126,7 @@ static struct {
 	{"SAM2", GB_UNL_SACHEN_MMC2},
 	{"ROCK", GB_MBC_AUTODETECT}, // TODO
 	{"NGHK", GB_MBC_AUTODETECT}, // TODO
-	{"GB81", GB_MBC_AUTODETECT}, // TODO
+	{"GB81", GB_UNL_GGB81},
 	{"TPP1", GB_MBC_AUTODETECT}, // TODO
 
 	{NULL, GB_MBC_AUTODETECT},
@@ -211,6 +211,9 @@ static enum GBMemoryBankControllerType _detectUnlMBC(const uint8_t* mem, size_t
 			return GB_UNL_BBD;
 		}
 		break;
+	case 0x79f34594: // DATA.
+	case 0x7e8c539b: // TD-SOFT
+		return GB_UNL_GGB81;
 	case 0x20d092e2:
 	case 0xd2b57657:
 		if (cart->type == 0x01) { // Make sure we're not using a "fixed" version
@@ -479,6 +482,11 @@ void GBMBCInit(struct GB* gb) {
 	case GB_UNL_LI_CHENG:
 		gb->memory.mbcWrite = _GBLiCheng;
 		break;
+	case GB_UNL_GGB81:
+		gb->memory.mbcWrite = _GBGGB81;
+		gb->memory.mbcRead = _GBGGB81Read;
+		gb->memory.mbcReadBank1 = true;
+		break;
 	case GB_UNL_SACHEN_MMC1:
 		gb->memory.mbcWrite = _GBSachen;
 		gb->memory.mbcRead = _GBSachenMMC1Read;

src/gb/mbc/mbc-private.h

@@ -36,6 +36,7 @@ void _GBNTNew(struct GB* gb, uint16_t address, uint8_t value);
 void _GBBBD(struct GB* gb, uint16_t address, uint8_t value);
 void _GBHitek(struct GB* gb, uint16_t address, uint8_t value);
 void _GBLiCheng(struct GB* gb, uint16_t address, uint8_t value);
+void _GBGGB81(struct GB* gb, uint16_t address, uint8_t value);
 void _GBSachen(struct GB* gb, uint16_t address, uint8_t value);
 
 uint8_t _GBMBC2Read(struct GBMemory*, uint16_t address);
@@ -50,6 +51,7 @@ uint8_t _GBHuC3Read(struct GBMemory*, uint16_t address);
 uint8_t _GBPKJDRead(struct GBMemory*, uint16_t address);
 uint8_t _GBBBDRead(struct GBMemory*, uint16_t address);
 uint8_t _GBHitekRead(struct GBMemory*, uint16_t address);
+uint8_t _GBGGB81Read(struct GBMemory*, uint16_t address);
 uint8_t _GBSachenMMC1Read(struct GBMemory*, uint16_t address);
 uint8_t _GBSachenMMC2Read(struct GBMemory*, uint16_t address);
 

src/gb/mbc/unlicensed.c

@@ -362,6 +362,37 @@ uint8_t _GBHitekRead(struct GBMemory* memory, uint16_t address) {
 	}
 }
 
+static const uint8_t _ggb81DataReordering[8][8] = {
+	{ 0, 1, 2, 3, 4, 5, 6, 7 },
+	{ 0, 2, 1, 3, 4, 6, 5, 7 },
+	{ 0, 6, 5, 3, 4, 2, 1, 7 },
+	{ 0, 5, 1, 3, 4, 2, 6, 7 },
+	{ 0, 5, 2, 3, 4, 1, 6, 7 },
+	{ 0, 2, 6, 3, 4, 5, 1, 7 },
+	{ 0, 1, 6, 3, 4, 2, 5, 7 },
+	{ 0, 2, 5, 3, 4, 6, 1, 7 },
+};
+
+void  _GBGGB81(struct GB* gb, uint16_t address, uint8_t value) {
+	struct GBMemory* memory = &gb->memory;
+	switch (address & 0xF0FF) {
+	case 0x2001:
+		memory->mbcState.bbd.dataSwapMode = value & 0x07;
+		break;
+	}
+	_GBMBC5(gb, address, value);
+}
+
+uint8_t _GBGGB81Read(struct GBMemory* memory, uint16_t address) {
+	switch (address >> 14) {
+	case 0:
+	default:
+		return memory->romBank[address & (GB_SIZE_CART_BANK0 - 1)];
+	case 1:
+		return _reorderBits(memory->romBank[address & (GB_SIZE_CART_BANK0 - 1)], _ggb81DataReordering[memory->mbcState.bbd.dataSwapMode]);
+	}
+}
+
 void  _GBLiCheng(struct GB* gb, uint16_t address, uint8_t value) {
     if (address > 0x2100 && address < 0x3000) {
         return;

src/gb/memory.c

@@ -816,6 +816,7 @@ void GBMemorySerialize(const struct GB* gb, struct GBSerializedState* state) {
 		break;
 	case GB_UNL_BBD:
 	case GB_UNL_HITEK:
+	case GB_UNL_GGB81:
 		state->memory.bbd.dataSwapMode = memory->mbcState.bbd.dataSwapMode;
 		state->memory.bbd.bankSwapMode = memory->mbcState.bbd.bankSwapMode;
 		break;
@@ -978,6 +979,7 @@ void GBMemoryDeserialize(struct GB* gb, const struct GBSerializedState* state) {
 		break;
 	case GB_UNL_BBD:
 	case GB_UNL_HITEK:
+	case GB_UNL_GGB81:
 		memory->mbcState.bbd.dataSwapMode = state->memory.bbd.dataSwapMode & 0x7;
 		memory->mbcState.bbd.bankSwapMode = state->memory.bbd.bankSwapMode & 0x7;
 		break;

src/gb/overrides.c

@@ -695,6 +695,7 @@ static const struct GBCartridgeOverride _overrides[] = {
 	{ 0xBC75D7B8, GB_MODEL_AUTODETECT, GB_UNL_NT_NEW, { 0 } }, // Pokemon - Mewtwo Strikes Back
 	{ 0xFF0B60CC, GB_MODEL_AUTODETECT, GB_UNL_NT_NEW, { 0 } }, // Shuma Baolong 02 4
 	{ 0x14A992A6, GB_MODEL_AUTODETECT, GB_UNL_NT_NEW, { 0 } }, // /Street Fighter Zero 4
+	{ 0x3EF5AFB2, GB_MODEL_AUTODETECT, GB_UNL_LI_CHENG, { 0 } }, // Pokemon Jade Version (Telefang Speed bootleg)
 
 	{ 0, 0, 0, { 0 } }
 };

src/platform/qt/GameBoy.cpp

@@ -40,6 +40,7 @@ static const QList<GBMemoryBankControllerType> s_mbcList{
 	GB_UNL_NT_NEW,
 	GB_UNL_BBD,
 	GB_UNL_HITEK,
+	GB_UNL_GGB81,
 	GB_UNL_LI_CHENG,
 	GB_UNL_SACHEN_MMC1,
 	GB_UNL_SACHEN_MMC2,
@@ -97,6 +98,7 @@ QString GameBoy::mbcName(GBMemoryBankControllerType mbc) {
 		s_mbcNames[GB_UNL_PKJD] = tr("Pokémon Jade/Diamond");
 		s_mbcNames[GB_UNL_BBD] = tr("BBD");
 		s_mbcNames[GB_UNL_HITEK] = tr("Hitek");
+		s_mbcNames[GB_UNL_GGB81] = tr("GGB-81");
 		s_mbcNames[GB_UNL_LI_CHENG] = tr("Li Cheng");
 		s_mbcNames[GB_UNL_SACHEN_MMC1] = tr("Sachen (MMC1)");
 		s_mbcNames[GB_UNL_SACHEN_MMC2] = tr("Sachen (MMC2)");