fix " #1454 NAND games won't save " by continuing my sloppy fixes from r5052 and r5053 while also removing some of r4880 "optimize read/writes to NAND" since that kind of logic should be handled in the file IO layer even if it isn't now, otherwise the logic is too redundant and complicated spread around the codebase. In the future we need to evaluate using EnablePositionCache() on all the mc.cpp operations

desmume/src/addons/slot1_retail_nand.cpp

@@ -45,8 +45,9 @@ private:
 
 	u32 mode;
 	u32 handle_save;
+
+	//current NAND read/write cursor
 	u32 save_adr;
-	u32 save_start_adr;
 
 public:
 	virtual Slot1Info const* info()
@@ -61,7 +62,7 @@ public:
 		protocol.chipId = gameInfo.chipID;
 		protocol.gameCode = T1ReadLong((u8*)gameInfo.header.gameCode,0);
 
-		save_start_adr = 0;
+		save_adr = 0;
 		handle_save = 0;
 		mode = 0;
 		subAdr = T1ReadWord(gameInfo.header.reserved2, 0x6) << 17;
@@ -81,6 +82,11 @@ public:
 		return protocol.read_GCDATAIN(PROCNUM);
 	}
 
+	void setProtocolAddress()
+	{
+		protocol.address = (protocol.command.bytes[1] << 24) | (protocol.command.bytes[2] << 16) | (protocol.command.bytes[3] << 8) | protocol.command.bytes[4];
+	}
+
 	virtual void slot1client_startOperation(eSlot1Operation operation)
 	{
 		//INFO("Start command: %02X%02X%02X%02X%02X%02X%02X%02X\t",
@@ -92,18 +98,19 @@ public:
 		switch(operation)
 		{
 			case eSlot1Operation_00_ReadHeader_Unencrypted:
-				protocol.address = (protocol.command.bytes[1] << 24) | (protocol.command.bytes[2] << 16) | (protocol.command.bytes[3] << 8) | protocol.command.bytes[4];
+				setProtocolAddress();
 				rom.start(operation,protocol.address);
 				break;
 
-			//case eSlot1Operation_B7_Read:  //zero 15-sep-2014 - this was removed during epoch of addon re-engineering to fix a bug
-
 			case eSlot1Operation_2x_SecureAreaLoad:
 				//don't re-generate address here. it was already done, according to different rules, for this operation
 				rom.start(operation,protocol.address);
 				return;
 		}
 
+		//subsequent commands should have access to the address set this way
+		setProtocolAddress();
+
 		//handle special commands ourselves
 		int cmd = protocol.command.bytes[0];
 		switch(cmd)
@@ -120,11 +127,7 @@ public:
 			//Nand Write Page
 			case 0x81:
 				mode = cmd;
-				if (save_start_adr != (protocol.address & gameInfo.mask) - subAdr)
+				save_adr = (protocol.address & gameInfo.mask) - subAdr;
-				{
-					save_start_adr = save_adr = (protocol.address & gameInfo.mask) - subAdr;
-					MMU_new.backupDevice.seek(save_start_adr);
-				}
 				handle_save = 1;
 				break;
 
@@ -142,11 +145,7 @@ public:
 				if (handle_save)
 				{
 					mode = cmd;
-					if (save_start_adr != (protocol.address & gameInfo.mask) - subAdr)
+					save_adr = (protocol.address & gameInfo.mask) - subAdr;
-					{
-						save_start_adr = save_adr = (protocol.address & gameInfo.mask) - subAdr;
-						MMU_new.backupDevice.seek(save_start_adr);
-					}
 				}
 				else
 				{
@@ -156,8 +155,7 @@ public:
 
 			case 0xB2: //Set save position
 				mode = cmd;
-				save_start_adr = save_adr = (protocol.address & gameInfo.mask) - subAdr;
+				save_adr = (protocol.address & gameInfo.mask) - subAdr;
-				MMU_new.backupDevice.seek(save_start_adr);
 				handle_save = 1;
 				break;
 		}
@@ -278,7 +276,7 @@ public:
 		os->write32le(mode);
 		os->write32le(handle_save);
 		os->write32le(save_adr);
-		os->write32le(save_start_adr);
+		os->write32le((u32)0);
 		os->write32le(subAdr);
 	}
 
@@ -297,7 +295,8 @@ public:
 			is->read32le(&mode);
 			is->read32le(&handle_save);
 			is->read32le(&save_adr);
-			is->read32le(&save_start_adr);
+			u32 junk;
+			is->read32le(&junk);
 			is->read32le(&subAdr);
 		}
 	}