void gfxMutexEnter(gfxMutex *pmutex) {
	INTERRUPTS_OFF();
	while (pmutex[0]) {
		INTERRUPTS_ON();
		gfxYield();
		INTERRUPTS_OFF();
	}
	pmutex[0] = 1;
	INTERRUPTS_ON();
}
void gfxSleepMicroseconds(delaytime_t ms) {
	systemticks_t	starttm, delay;

	// Safety first
	switch (ms) {
	case TIME_IMMEDIATE:
		return;
	case TIME_INFINITE:
		while(1)
			gfxYield();
		return;
	}

	// Convert our delay to ticks
	delay = gfxMillisecondsToTicks(ms/1000);
	starttm = gfxSystemTicks();

	do {
		gfxYield();
	} while (gfxSystemTicks() - starttm < delay);
}
bool_t gfxSemWait(gfxSem *psem, delaytime_t ms) {
	systemticks_t	starttm, delay;

	// Convert our delay to ticks
	starttm = 0;
	switch (ms) {
	case TIME_IMMEDIATE:
		delay = TIME_IMMEDIATE;
		break;
	case TIME_INFINITE:
		delay = TIME_INFINITE;
		break;
	default:
		delay = gfxMillisecondsToTicks(ms);
		if (!delay) delay = 1;
		starttm = gfxSystemTicks();
	}

	INTERRUPTS_OFF();
	while (psem->cnt <= 0) {
		INTERRUPTS_ON();
		// Check if we have exceeded the defined delay
		switch (delay) {
		case TIME_IMMEDIATE:
			return FALSE;
		case TIME_INFINITE:
			break;
		default:
			if (gfxSystemTicks() - starttm >= delay)
				return FALSE;
			break;
		}
		gfxYield();
		INTERRUPTS_OFF();
	}
	psem->cnt--;
	INTERRUPTS_ON();
	return TRUE;
}
示例#4
0
static void _ltdc_reload(void) {
	LTDC->SRCR |= LTDC_SRCR_IMR;
	while (LTDC->SRCR & (LTDC_SRCR_IMR | LTDC_SRCR_VBR))
		gfxYield();
}
示例#5
0
static DECLARE_THREAD_FUNCTION(GTimerThreadHandler, arg) {
	GTimer			*pt;
	systemticks_t	tm;
	systemticks_t	nxtTimeout;
	systemticks_t	lastTime;
	GTimerFunction	fn;
	void			*param;
	(void)			arg;

	nxtTimeout = TIME_INFINITE;
	lastTime = 0;
	while(1) {
		/* Wait for work to do. */
		gfxYield();					// Give someone else a go no matter how busy we are
		gfxSemWait(&waitsem, nxtTimeout);
		
	restartTimerChecks:
	
		// Our reference time
		tm = gfxSystemTicks();
		nxtTimeout = TIME_INFINITE;
		
		/* We need to obtain the mutex */
		gfxMutexEnter(&mutex);

		if (pTimerHead) {
			pt = pTimerHead;
			do {
				// Do we have something to do for this timer?
				if ((pt->flags & GTIMER_FLG_JABBED) || (!(pt->flags & GTIMER_FLG_INFINITE) && TimeIsWithin(pt->when, lastTime, tm))) {
				
					// Is this timer periodic?
					if ((pt->flags & GTIMER_FLG_PERIODIC) && pt->period != TIME_IMMEDIATE) {
						// Yes - Update ready for the next period
						if (!(pt->flags & GTIMER_FLG_INFINITE)) {
							// We may have skipped a period.
							// We use this complicated formulae rather than a loop
							//	because the gcc compiler stuffs up the loop so that it
							//	either loops forever or doesn't get executed at all.
							pt->when += ((tm + pt->period - pt->when) / pt->period) * pt->period;
						}

						// We are definitely no longer jabbed
						pt->flags &= ~GTIMER_FLG_JABBED;
						
					} else {
						// No - get us off the timers list
						if (pt->next == pt)
							pTimerHead = 0;
						else {
							pt->next->prev = pt->prev;
							pt->prev->next = pt->next;
							if (pTimerHead == pt)
								pTimerHead = pt->next;
						}
						pt->flags = 0;
					}
					
					// Call the callback function
					fn = pt->fn;
					param = pt->param;
					gfxMutexExit(&mutex);
					fn(param);
					
					// We no longer hold the mutex, the callback function may have taken a while
					// and our list may have been altered so start again!
					goto restartTimerChecks;
				}
				
				// Find when we next need to wake up
				if (!(pt->flags & GTIMER_FLG_INFINITE) && pt->when - tm < nxtTimeout)
					nxtTimeout = (pt->when - tm)/ticks2ms;
				pt = pt->next;
			} while(pt != pTimerHead);
		}

		// Ready for the next loop
		lastTime = tm;
		gfxMutexExit(&mutex);
	}
	THREAD_RETURN(0);
}