maple: raise interrupt on vblank when maple bus is occupied

Raise a maple interrupt at the next vblank when the host occupies the
maple bus to read the lightgun position. Fixes RevolveR single shot
issue since the game is waiting for the interrupt.
Issue #1369

core/hw/maple/maple_cfg.cpp

@@ -10,6 +10,7 @@
 MapleInputState mapleInputState[4];
 extern bool maple_ddt_pending_reset;
 extern std::vector<std::pair<u32, std::vector<u32>>> mapleDmaOut;
+extern bool SDCKBOccupied;
 
 void (*MapleConfigMap::UpdateVibration)(u32 port, float power, float inclination, u32 duration_ms);
 
@@ -414,6 +415,7 @@ void mcfg_DestroyDevices(bool full)
 void mcfg_SerializeDevices(Serializer& ser)
 {
 	ser << maple_ddt_pending_reset;
+	ser << SDCKBOccupied;
 	ser << (u32)mapleDmaOut.size();
 	for (const auto& pair : mapleDmaOut)
 	{
@@ -446,6 +448,8 @@ void mcfg_DeserializeDevices(Deserializer& deser)
 		deser.skip<bool>(); // EEPROM_loaded
 	}
 	deser >> maple_ddt_pending_reset;
+	if (deser.version() >= Deserializer::V47)
+		deser >> SDCKBOccupied;
 	mapleDmaOut.clear();
 	if (deser.version() >= Deserializer::V23)
 	{

core/hw/maple/maple_if.cpp

@@ -32,6 +32,7 @@ int maple_schid;
 
 static void maple_DoDma();
 static void maple_handle_reconnect();
+static int maple_schd(int tag, int cycles, int jitter, void *arg);
 
 //really hackish
 //misses delay , and stop/start implementation
@@ -40,30 +41,39 @@ static void maple_handle_reconnect();
 bool maple_ddt_pending_reset;
 // pending DMA xfers
 std::vector<std::pair<u32, std::vector<u32>>> mapleDmaOut;
+bool SDCKBOccupied;
 
 void maple_vblank()
 {
 	if (SB_MDEN & 1)
 	{
-		if (SB_MDTSEL == 1)
+		if (SDCKBOccupied)
 		{
-			if (maple_ddt_pending_reset)
-			{
-				DEBUG_LOG(MAPLE, "DDT vblank ; reset pending");
-			}
-			else
-			{
-				DEBUG_LOG(MAPLE, "DDT vblank");
-				SB_MDST = 1;
-				maple_DoDma();
-				// if trigger reset is manual, mark it as pending
-				if ((SB_MSYS >> 12) & 1)
-					maple_ddt_pending_reset = true;
-			}
+			maple_schd(0, 0, 0, nullptr);
+			SDCKBOccupied = false;
 		}
 		else
 		{
-			maple_ddt_pending_reset = false;
+			if (SB_MDTSEL == 1)
+			{
+				if (maple_ddt_pending_reset)
+				{
+					DEBUG_LOG(MAPLE, "DDT vblank ; reset pending");
+				}
+				else
+				{
+					DEBUG_LOG(MAPLE, "DDT vblank");
+					SB_MDST = 1;
+					maple_DoDma();
+					// if trigger reset is manual, mark it as pending
+					if ((SB_MSYS >> 12) & 1)
+						maple_ddt_pending_reset = true;
+				}
+			}
+			else
+			{
+				maple_ddt_pending_reset = false;
+			}
 		}
 	}
 	if (settings.platform.isConsole())
@@ -152,7 +162,6 @@ static void maple_DoDma()
 	const bool swap_msb = (SB_MMSEL == 0);
 	u32 xfer_count = 0;
 	bool last = false;
-	bool occupy = false;
 	while (!last)
 	{
 		u32 header_1 = ReadMem32_nommu(addr);
@@ -245,7 +254,7 @@ static void maple_DoDma()
 		{
 			u32 bus = (header_1 >> 16) & 3;
 			if (MapleDevices[bus][5]) {
-				occupy = MapleDevices[bus][5]->get_lightgun_pos();
+				SDCKBOccupied = SDCKBOccupied || MapleDevices[bus][5]->get_lightgun_pos();
 				xfer_count++;
 			}
 			addr += 1 * 4;
@@ -253,6 +262,7 @@ static void maple_DoDma()
 		break;
 
 		case MP_SDCKBOccupyCancel:
+			SDCKBOccupied = false;
 			addr += 1 * 4;
 			break;
 
@@ -273,7 +283,7 @@ static void maple_DoDma()
 
 	// Maple bus max speed: 2 Mb/s, actual speed: 1 Mb/s
 	//printf("Maple XFER size %d bytes - %.2f ms\n", xfer_count, xfer_count * 1000.0f / (128 * 1024));
-	if (!occupy)
+	if (!SDCKBOccupied)
 		sh4_sched_request(maple_schid, std::min((u64)xfer_count * (SH4_MAIN_CLOCK / (256 * 1024)), (u64)SH4_MAIN_CLOCK));
 }
 

core/serialize.h

@@ -72,7 +72,8 @@ public:
 		V44,
 		V45,
 		V46,
-		Current = V46,
+		V47,
+		Current = V47,
 
 		Next = Current + 1,
 	};

tests/src/serialize_test.cpp

@@ -32,7 +32,7 @@ TEST_F(SerializeTest, SizeTest)
 	std::vector<char> data(30000000);
 	Serializer ser(data.data(), data.size());
 	dc_serialize(ser);
-	ASSERT_EQ(28191437u, ser.size());
+	ASSERT_EQ(28191438u, ser.size());
 }