RTC: Automatically detect timezone

Author: TheTechnician27

pcsx2-qt/Settings/EmulationSettingsWidget.cpp

@@ -159,9 +159,8 @@ EmulationSettingsWidget::EmulationSettingsWidget(SettingsWindow* settings_dialog
 	dialog()->registerWidgetHelp(m_ui.manuallySetRealTimeClock, tr("Manually Set Real-Time Clock"), tr("Unchecked"),
 		tr("Manually set a real-time clock to use for the virtual PlayStation 2 instead of using your OS' system clock."));
 	dialog()->registerWidgetHelp(m_ui.rtcDateTime, tr("Real-Time Clock"), tr("Current date and time"),
-		tr("Real-time clock (RTC) used by the virtual PlayStation 2. Date format is the same as the one used by your OS. "
-		   "This time is only applied upon booting the PS2; changing it while in-game will have no effect. "
-		   "NOTE: This assumes you have your PS2 set to the default timezone of GMT+0 and default DST of Summer Time. "
+		tr("Real-time clock (RTC) used by the virtual PlayStation 2. Date format is the same as the one used by your OS.<br>"
+		   "This time is only applied upon booting the PS2; changing it while in-game will have no effect.<br>"
 		   "Some games require an RTC date/time set after their release date."));
 
 	updateOptimalFramePacing();

pcsx2/CDVD/CDVD.cpp

@@ -36,6 +36,7 @@
 cdvdStruct cdvd;
 
 s64 PSXCLK = 36864000;
+const s32 GMT9_OFFSET_SECONDS = 32400; // 9 * 60 * 60
 
 static constexpr u8 monthmap[13] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
 
@@ -920,69 +921,88 @@ void cdvdReset()
 	cdvd.ReadTime = cdvdBlockReadTime(MODE_DVDROM);
 	cdvd.RotSpeed = cdvdRotationTime(MODE_DVDROM);
 
+	ReadOSDConfigParames();
+
+	// Print time zone offset, DST, date format, time format, and system time basis.
+	DevCon.WriteLn(Color_StrongGreen, configParams1.timezoneOffset < 0 ? "Time Zone Offset: GMT%03d:%02d" : "Time Zone Offset: GMT+%02d:%02d",
+				   configParams1.timezoneOffset / 60, std::abs(configParams1.timezoneOffset % 60));
+	DevCon.WriteLn(Color_StrongGreen, "DST: %s Time", configParams2.daylightSavings ? "Summer" : "Winter");
+	DevCon.WriteLn(Color_StrongGreen, "Time Format: %s-Hour", configParams2.timeFormat ? "12" : "24");
+ 	DevCon.WriteLn(Color_StrongGreen, "Date Format: %s", configParams2.dateFormat ? (configParams2.dateFormat == 2 ? "DD/MM/YYYY" : "MM/DD/YYYY") : "YYYY/MM/DD");
+	DevCon.WriteLn(Color_StrongGreen, "System Time Basis: %s",
+				   EmuConfig.ManuallySetRealTimeClock ? "Manual RTC" : g_InputRecording.isActive() ? "Default Input Recording Time" : "Operating System Time");
+
+	std::tm input_tm{};
+	std::tm resulting_tm{};
+
+	const int bios_settings_offset_seconds = 60 * (configParams1.timezoneOffset + configParams2.daylightSavings * 60);
+
+	// CDVD internally uses GMT+9, 1-indexed months, and year offset of 2000 instead of 1900.
 	if (EmuConfig.ManuallySetRealTimeClock)
 	{
-		// Convert to GMT+9 (assumes GMT+0)
-		std::tm tm{};
-		tm.tm_sec = EmuConfig.RtcSecond;
-		tm.tm_min = EmuConfig.RtcMinute;
-		tm.tm_hour = EmuConfig.RtcHour;
-		tm.tm_mday = EmuConfig.RtcDay;
-		tm.tm_mon = EmuConfig.RtcMonth - 1;
-		tm.tm_year = EmuConfig.RtcYear + 100; // 2000 - 1900
-		tm.tm_isdst = 1;
-
-		// Need this instead of mktime for timezone independence
-		std::time_t t = 0;
-		#if defined(_WIN32)
-			t = _mkgmtime(&tm) + 32400; //60 * 60 * 9 for GMT+9
-			gmtime_s(&tm, &t);
-		#else
-			t = timegm(&tm) + 32400;
-			gmtime_r(&t, &tm);
-		#endif
-
-		cdvd.RTC.second = tm.tm_sec;
-		cdvd.RTC.minute = tm.tm_min;
-		cdvd.RTC.hour = tm.tm_hour;
-		cdvd.RTC.day = tm.tm_mday;
-		cdvd.RTC.month = tm.tm_mon + 1;
-		cdvd.RTC.year = tm.tm_year - 100;
-	}
-	// If we are recording, always use the same RTC setting
-	// for games that use the RTC to seed their RNG -- this is very important to be the same everytime!
+		resulting_tm.tm_sec = EmuConfig.RtcSecond;
+		resulting_tm.tm_min = EmuConfig.RtcMinute;
+		resulting_tm.tm_hour = EmuConfig.RtcHour;
+		resulting_tm.tm_mday = EmuConfig.RtcDay;
+		resulting_tm.tm_mon = EmuConfig.RtcMonth - 1;
+		resulting_tm.tm_year = EmuConfig.RtcYear + 100;
+		resulting_tm.tm_isdst = 0;
+
+		// Work backwards to input time by accounting for BIOS settings and GMT+9 defaultism.
+#if defined(_WIN32)
+		const std::time_t input_time = _mkgmtime(&resulting_tm) + GMT9_OFFSET_SECONDS - bios_settings_offset_seconds;
+		gmtime_s(&input_tm, &input_time);
+#else
+		const std::time_t input_time = timegm(&resulting_tm) + GMT9_OFFSET_SECONDS - bios_settings_offset_seconds;
+		gmtime_r(&input_time, &input_tm);
+#endif
+	}
 	else if (g_InputRecording.isActive())
 	{
-		Console.WriteLn("Input Recording Active - Using Constant RTC of 04-03-2020 (DD-MM-YYYY)");
-		// Why not just 0 everything? Some games apparently require the date to be valid in terms of when
-		// the PS2 / Game actually came out. (MGS3).  So set it to a value well beyond any PS2 game's release date.
-		cdvd.RTC.second = 0;
-		cdvd.RTC.minute = 0;
-		cdvd.RTC.hour = 0;
-		cdvd.RTC.day = 4;
-		cdvd.RTC.month = 3;
-		cdvd.RTC.year = 20;
+		// Legacy default value if manual RTC is off to preserve compat with old input recordings (RNG seeding).
+		// Well beyond any PS2 game's release date because some games require a valid date in terms of when the PS2 / Game actually came out (MGS3).
+		input_tm.tm_sec = 0;
+		input_tm.tm_min = 0;
+		input_tm.tm_hour = 0;
+		input_tm.tm_mday = 4;
+		input_tm.tm_mon = 2;
+		input_tm.tm_year = 120;
+		input_tm.tm_isdst = 0;
+
+#if defined(_WIN32)
+		const std::time_t resulting_time = _mkgmtime(&input_tm) - GMT9_OFFSET_SECONDS + bios_settings_offset_seconds;
+		gmtime_s(&resulting_tm, &resulting_time);
+#else
+		const std::time_t resulting_time = timegm(&input_tm) - GMT9_OFFSET_SECONDS + bios_settings_offset_seconds;
+		gmtime_r(&resulting_time, &resulting_tm);
+#endif
 	}
 	else
 	{
-		// CDVD internally uses GMT+9.  If you think the time's wrong, you're wrong.
-		// Set up your time zone and winter/summer in the BIOS.  No PS2 BIOS I know of features automatic DST.
-		const std::time_t utc_time = std::time(nullptr);
-		const std::time_t gmt9_time = (utc_time + 32400); //60 * 60 * 9
-		struct tm curtime = {};
+		// User must set time zone and winter/summer DST in the BIOS for correct time.
+		const std::time_t input_time = std::time(nullptr) + GMT9_OFFSET_SECONDS;
+		const std::time_t resulting_time = input_time - GMT9_OFFSET_SECONDS + bios_settings_offset_seconds;
+
 #ifdef _MSC_VER
-		gmtime_s(&curtime, &gmt9_time);
+		gmtime_s(&input_tm, &input_time);
+		gmtime_s(&resulting_tm, &resulting_time);
 #else
-		gmtime_r(&gmt9_time, &curtime);
+		gmtime_r(&input_time, &input_tm);
+		gmtime_r(&resulting_time, &resulting_tm);
 #endif
-		cdvd.RTC.second = static_cast<u8>(curtime.tm_sec);
-		cdvd.RTC.minute = static_cast<u8>(curtime.tm_min);
-		cdvd.RTC.hour = static_cast<u8>(curtime.tm_hour);
-		cdvd.RTC.day = static_cast<u8>(curtime.tm_mday);
-		cdvd.RTC.month = static_cast<u8>(curtime.tm_mon + 1); // WX returns Jan as "0"
-		cdvd.RTC.year = static_cast<u8>(curtime.tm_year - 100); // offset from 2000
 	}
 
+	cdvd.RTC.second = static_cast<u8>(input_tm.tm_sec);
+	cdvd.RTC.minute = static_cast<u8>(input_tm.tm_min);
+	cdvd.RTC.hour = static_cast<u8>(input_tm.tm_hour);
+	cdvd.RTC.day = static_cast<u8>(input_tm.tm_mday);
+	cdvd.RTC.month = static_cast<u8>(input_tm.tm_mon + 1);
+	cdvd.RTC.year = static_cast<u8>(input_tm.tm_year - 100); // offset from 2000
+
+	DevCon.WriteLn(Color_StrongGreen, "Resulting System Time: 20%02u-%02u-%02u %02u:%02u:%02u",
+				   resulting_tm.tm_year - 100, resulting_tm.tm_mon + 1, resulting_tm.tm_mday,
+				   resulting_tm.tm_hour, resulting_tm.tm_min, resulting_tm.tm_sec);
+
 	cdvdCtrlTrayClose();
 }
 

pcsx2/Config.h

@@ -1314,7 +1314,7 @@ struct Pcsx2Config
 		InhibitScreensaver : 1,
 		BackupSavestate : 1,
 		McdFolderAutoManage : 1,
-		ManuallySetRealTimeClock : 1,
+		ManuallySetRealTimeClock : 1, // passes user-set real-time clock information to cdvd at startup
 
 		HostFs : 1,
 

pcsx2/ps2/BiosTools.cpp

@@ -65,9 +65,11 @@ void ReadOSDConfigParames()
 	configParams1.version = (params[2] & 0xE0) >> 5; // OSD Ver (Not sure but best guess).
 	configParams1.language = params[2] & 0x1F; // Language.
 	configParams1.timezoneOffset = params[4] | ((u32)(params[3] & 0x7) << 8);  // Timezone offset in minutes.
-
 	// Region settings for time/date and extended language
 	configParams2.UC[1] = ((u32)params[3] & 0x78) << 1; // Daylight Savings, 24hr clock, Date format
+	configParams2.daylightSavings = configParams2.UC[1] & 0x10 ? 1 : 0;
+	configParams2.timeFormat = configParams2.UC[1] & 0x20 ? 1 : 0;
+	configParams2.dateFormat = configParams2.UC[1] & 0x80 ? 2 : (configParams2.UC[1] & 0x40 ? 1 : 0);
 	// FIXME: format, version and language are set manually by the bios. Not sure if any game needs them, but it seems to set version to 2 and duplicate the language value.
 	configParams2.version = 2;
 	configParams2.language = configParams1.language;

pcsx2/ps2/BiosTools.h

@@ -43,7 +43,7 @@ typedef struct
 			/** LANGUAGE_??? value */
 			/*16*/ u32 language : 5;
 			/** timezone minutes offset from gmt */
-			/*21*/ u32 timezoneOffset : 11;
+			/*21*/ s32 timezoneOffset : 11;
 		};
 
 		u8  UC[4];
@@ -63,7 +63,7 @@ typedef struct
 
 			/*00*/ u8 reserved : 4;
 			/** 0=standard(winter), 1=daylight savings(summer) */
-			/*04*/ u8 daylightSaving : 1;
+			/*04*/ u8 daylightSavings : 1;
 			/** 0=24 hour, 1=12 hour */
 			/*05*/ u8 timeFormat : 1;
 			/** 0=YYYYMMDD, 1=MMDDYYYY, 2=DDMMYYYY */