PSP: found bug in fast getMillis() implementation. Fixed it by adding a fixed amount to the time counter.

svn-id: r49485

4 files changed, 55 insertions, 7 deletions

diff --git a/backends/platform/psp/osys_psp.cpp b/backends/platform/psp/osys_psp.cpp
index a36ae1847f..2043a4bef2 100644
--- a/backends/platform/psp/osys_psp.cpp
+++ b/backends/platform/psp/osys_psp.cpp
@@ -37,7 +37,6 @@
 #include "backends/platform/psp/psppixelformat.h"
 #include "backends/platform/psp/osys_psp.h"
 #include "backends/platform/psp/powerman.h"
-#include "backends/platform/psp/thread.h"
 
 #include "backends/saves/psp/psp-saves.h"
 #include "backends/timer/default/default-timer.h"
@@ -300,7 +299,7 @@ bool OSystem_PSP::pollEvent(Common::Event &event) {
 }
 
 uint32 OSystem_PSP::getMillis() {
-	return PspThread::getMillis();
+	return _pspRtc.getMillis();
 }
 
 void OSystem_PSP::delayMillis(uint msecs) {
diff --git a/backends/platform/psp/osys_psp.h b/backends/platform/psp/osys_psp.h
index 3f075d0139..a6c84ba39a 100644
--- a/backends/platform/psp/osys_psp.h
+++ b/backends/platform/psp/osys_psp.h
@@ -40,6 +40,7 @@
 #include "backends/platform/psp/input.h"
 #include "backends/platform/psp/audio.h"
 #include "backends/timer/psp/timer.h"
+#include "backends/platform/psp/thread.h"
 
 #include <SDL.h>
 
@@ -59,6 +60,7 @@ private:
 	InputHandler _inputHandler;
 	PspAudio _audio;
 	PspTimer _pspTimer;
+	PspRtc _pspRtc;
 
 	void initSDL();
 
diff --git a/backends/platform/psp/thread.cpp b/backends/platform/psp/thread.cpp
index 88e7b6fe38..4e7d5eada9 100644
--- a/backends/platform/psp/thread.cpp
+++ b/backends/platform/psp/thread.cpp
@@ -29,6 +29,7 @@
 #include <pspthreadman.h> 
 
 #include "backends/platform/psp/thread.h"
+#include "backends/platform/psp/trace.h"
  
 void PspThread::delayMillis(uint32 ms) {
 	sceKernelDelayThread(ms * 1000);
@@ -38,15 +39,49 @@ void PspThread::delayMicros(uint32 us) {
 	sceKernelDelayThread(us);
 }
 
-uint32 PspThread::getMillis() {
+void PspRtc::init() {						// init our starting ticks
 	uint32 ticks[2];
 	sceRtcGetCurrentTick((u64 *)ticks);
-	return (ticks[0]/1000);	
+
+	_startMillis = ticks[0]/1000;
+	_startMicros = ticks[0];
+	//_lastMillis = ticks[0]/1000;	//debug - only when we don't subtract startMillis
+}
+
+#define MS_LOOP_AROUND 4294967				/* We loop every 2^32 / 1000 = 71 minutes */
+#define MS_LOOP_CHECK  60000				/* Threading can cause weird mixups without this */
+
+// Note that after we fill up 32 bits ie 50 days we'll loop back to 0, which may cause 
+// unpredictable results
+uint32 PspRtc::getMillis() {
+	uint32 ticks[2];
+	
+	sceRtcGetCurrentTick((u64 *)ticks);		// can introduce weird thread delays
+	
+	uint32 millis = ticks[0]/1000;
+	millis -= _startMillis;					// get ms since start of program
+
+	if ((int)_lastMillis - (int)millis > MS_LOOP_CHECK) {		// we must have looped around
+		if (_looped == false) {					// check to make sure threads do this once
+			_looped = true;
+			_milliOffset += MS_LOOP_AROUND;		// add the needed offset
+			PSP_DEBUG_PRINT("looping around. last ms[%d], curr ms[%d]\n", _lastMillis, millis);
+		}	
+	} else {
+		_looped = false;
+	}
+	
+	_lastMillis = millis;	
+	
+	return millis + _milliOffset;
 }
 
-uint32 PspThread::getMicros() {
+uint32 PspRtc::getMicros() {
 	uint32 ticks[2];
+	
 	sceRtcGetCurrentTick((u64 *)ticks);
+	ticks[0] -= _startMicros;
+	
 	return ticks[0]; 
 }
 
diff --git a/backends/platform/psp/thread.h b/backends/platform/psp/thread.h
index e83eead68e..380159fa2d 100644
--- a/backends/platform/psp/thread.h
+++ b/backends/platform/psp/thread.h
@@ -32,8 +32,20 @@ class PspThread {
 public:
 	static void delayMillis(uint32 ms);
 	static void delayMicros(uint32 us);
-	static uint32 getMillis();
-	static uint32 getMicros();
+};
+
+class PspRtc {
+private:
+	uint32 _startMillis;
+	uint32 _startMicros;
+	uint32 _lastMillis;
+	uint32 _milliOffset;		// to prevent looping around of millis
+	bool _looped;				// make sure we only loop once
+public:
+	PspRtc() : _startMillis(0), _startMicros(0), _lastMillis(0), _milliOffset(0), _looped(false) { init(); }
+	void init();
+	uint32 getMillis();
+	uint32 getMicros();
 };
 
 enum ThreadPriority {