return usec;
}
+#ifdef CONFIG_NO_IDLE_HZ
+static unsigned long initial_match;
+static int match_posponed;
+#endif
+
static irqreturn_t
pxa_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
int next_match;
+ write_seqlock(&xtime_lock);
+
+#ifdef CONFIG_NO_IDLE_HZ
+ if (match_posponed) {
+ match_posponed = 0;
+ OSMR0 = initial_match;
+ }
+#endif
+
/* Loop until we get ahead of the free running timer.
* This ensures an exact clock tick count and time accuracy.
- * IRQs are disabled inside the loop to ensure coherence between
- * lost_ticks (updated in do_timer()) and the match reg value, so we
- * can use do_gettimeofday() from interrupt handlers.
+ * Since IRQs are disabled at this point, coherence between
+ * lost_ticks(updated in do_timer()) and the match reg value is
+ * ensured, hence we can use do_gettimeofday() from interrupt
+ * handlers.
*
* HACK ALERT: it seems that the PXA timer regs aren't updated right
* away in all cases when a write occurs. We therefore compare with
next_match = (OSMR0 += LATCH);
} while( (signed long)(next_match - OSCR) <= 8 );
+ write_sequnlock(&xtime_lock);
+
return IRQ_HANDLED;
}
static struct irqaction pxa_timer_irq = {
.name = "PXA Timer Tick",
- .flags = SA_INTERRUPT,
- .handler = pxa_timer_interrupt
+ .flags = SA_INTERRUPT | SA_TIMER,
+ .handler = pxa_timer_interrupt,
};
-void __init pxa_init_time(void)
+static void __init pxa_timer_init(void)
{
struct timespec tv;
- gettimeoffset = pxa_gettimeoffset;
set_rtc = pxa_set_rtc;
tv.tv_nsec = 0;
tv.tv_sec = pxa_get_rtc_time();
do_settimeofday(&tv);
- OSMR0 = 0; /* set initial match at 0 */
+ OIER = 0; /* disable any timer interrupts */
+ OSCR = LATCH*2; /* push OSCR out of the way */
+ OSMR0 = LATCH; /* set initial match */
OSSR = 0xf; /* clear status on all timers */
setup_irq(IRQ_OST0, &pxa_timer_irq);
- OIER |= OIER_E0; /* enable match on timer 0 to cause interrupts */
- OSCR = 0; /* initialize free-running timer, force first match */
+ OIER = OIER_E0; /* enable match on timer 0 to cause interrupts */
+ OSCR = 0; /* initialize free-running timer */
+}
+
+#ifdef CONFIG_NO_IDLE_HZ
+static int pxa_dyn_tick_enable_disable(void)
+{
+ /* nothing to do */
+ return 0;
+}
+
+static void pxa_dyn_tick_reprogram(unsigned long ticks)
+{
+ if (ticks > 1) {
+ initial_match = OSMR0;
+ OSMR0 = initial_match + ticks * LATCH;
+ match_posponed = 1;
+ }
+}
+
+static irqreturn_t
+pxa_dyn_tick_handler(int irq, void *dev_id, struct pt_regs *regs)
+{
+ if (match_posponed) {
+ match_posponed = 0;
+ OSMR0 = initial_match;
+ if ( (signed long)(initial_match - OSCR) <= 8 )
+ return pxa_timer_interrupt(irq, dev_id, regs);
+ }
+ return IRQ_NONE;
+}
+
+static struct dyn_tick_timer pxa_dyn_tick = {
+ .enable = pxa_dyn_tick_enable_disable,
+ .disable = pxa_dyn_tick_enable_disable,
+ .reprogram = pxa_dyn_tick_reprogram,
+ .handler = pxa_dyn_tick_handler,
+};
+#endif
+
+#ifdef CONFIG_PM
+static unsigned long osmr[4], oier;
+
+static void pxa_timer_suspend(void)
+{
+ osmr[0] = OSMR0;
+ osmr[1] = OSMR1;
+ osmr[2] = OSMR2;
+ osmr[3] = OSMR3;
+ oier = OIER;
}
+static void pxa_timer_resume(void)
+{
+ OSMR0 = osmr[0];
+ OSMR1 = osmr[1];
+ OSMR2 = osmr[2];
+ OSMR3 = osmr[3];
+ OIER = oier;
+
+ /*
+ * OSMR0 is the system timer: make sure OSCR is sufficiently behind
+ */
+ OSCR = OSMR0 - LATCH;
+}
+#else
+#define pxa_timer_suspend NULL
+#define pxa_timer_resume NULL
+#endif
+
+struct sys_timer pxa_timer = {
+ .init = pxa_timer_init,
+ .suspend = pxa_timer_suspend,
+ .resume = pxa_timer_resume,
+ .offset = pxa_gettimeoffset,
+#ifdef CONFIG_NO_IDLE_HZ
+ .dyn_tick = &pxa_dyn_tick,
+#endif
+};