X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=arch%2Farm%2Fmach-sa1100%2Ftime.c;h=a9799cb35b74aebe0d005adb6c547b83e92e5b21;hb=6b5cdf0f6d4dc3d98de20d6b0abe8500046f1cb1;hp=fdf7b016e7adeadfa5652ae9779803209eba3d91;hpb=e8b495fe09bc793ae26774e7b2667f7f658d56e2;p=linux-2.6-omap-h63xx.git diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c index fdf7b016e7a..a9799cb35b7 100644 --- a/arch/arm/mach-sa1100/time.c +++ b/arch/arm/mach-sa1100/time.c @@ -13,139 +13,112 @@ #include #include #include -#include +#include #include #include -#define RTC_DEF_DIVIDER (32768 - 1) -#define RTC_DEF_TRIM 0 +#define MIN_OSCR_DELTA 2 -static int sa1100_set_rtc(void) +static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id) { - unsigned long current_time = xtime.tv_sec; + struct clock_event_device *c = dev_id; - if (RTSR & RTSR_ALE) { - /* make sure not to forward the clock over an alarm */ - unsigned long alarm = RTAR; - if (current_time >= alarm && alarm >= RCNR) - return -ERESTARTSYS; - } - RCNR = current_time; - return 0; + /* Disarm the compare/match, signal the event. */ + OIER &= ~OIER_E0; + OSSR = OSSR_M0; + c->event_handler(c); + + return IRQ_HANDLED; } -/* IRQs are disabled before entering here from do_gettimeofday() */ -static unsigned long sa1100_gettimeoffset (void) +static int +sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c) { - unsigned long ticks_to_match, elapsed, usec; - - /* Get ticks before next timer match */ - ticks_to_match = OSMR0 - OSCR; - - /* We need elapsed ticks since last match */ - elapsed = LATCH - ticks_to_match; + unsigned long flags, next, oscr; - /* Now convert them to usec */ - usec = (unsigned long)(elapsed * (tick_nsec / 1000))/LATCH; + raw_local_irq_save(flags); + OIER |= OIER_E0; + next = OSCR + delta; + OSMR0 = next; + oscr = OSCR; + raw_local_irq_restore(flags); - return usec; + return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0; } -#ifdef CONFIG_NO_IDLE_HZ -static unsigned long initial_match; -static int match_posponed; -#endif - -static irqreturn_t -sa1100_timer_interrupt(int irq, void *dev_id) +static void +sa1100_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *c) { - unsigned int next_match; - - write_seqlock(&xtime_lock); + unsigned long flags; -#ifdef CONFIG_NO_IDLE_HZ - if (match_posponed) { - match_posponed = 0; - OSMR0 = initial_match; + switch (mode) { + case CLOCK_EVT_MODE_ONESHOT: + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + raw_local_irq_save(flags); + OIER &= ~OIER_E0; + OSSR = OSSR_M0; + raw_local_irq_restore(flags); + break; + + case CLOCK_EVT_MODE_RESUME: + case CLOCK_EVT_MODE_PERIODIC: + break; } -#endif - - /* - * Loop until we get ahead of the free running timer. - * This ensures an exact clock tick count and time accuracy. - * 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. - */ - do { - timer_tick(); - OSSR = OSSR_M0; /* Clear match on timer 0 */ - next_match = (OSMR0 += LATCH); - } while ((signed long)(next_match - OSCR) <= 0); +} - write_sequnlock(&xtime_lock); +static struct clock_event_device ckevt_sa1100_osmr0 = { + .name = "osmr0", + .features = CLOCK_EVT_FEAT_ONESHOT, + .shift = 32, + .rating = 200, + .cpumask = CPU_MASK_CPU0, + .set_next_event = sa1100_osmr0_set_next_event, + .set_mode = sa1100_osmr0_set_mode, +}; - return IRQ_HANDLED; +static cycle_t sa1100_read_oscr(void) +{ + return OSCR; } +static struct clocksource cksrc_sa1100_oscr = { + .name = "oscr", + .rating = 200, + .read = sa1100_read_oscr, + .mask = CLOCKSOURCE_MASK(32), + .shift = 20, + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + static struct irqaction sa1100_timer_irq = { - .name = "SA11xx Timer Tick", + .name = "ost0", .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, - .handler = sa1100_timer_interrupt, + .handler = sa1100_ost0_interrupt, + .dev_id = &ckevt_sa1100_osmr0, }; static void __init sa1100_timer_init(void) { - unsigned long flags; - - set_rtc = sa1100_set_rtc; - OIER = 0; /* disable any timer interrupts */ OSSR = 0xf; /* clear status on all timers */ - setup_irq(IRQ_OST0, &sa1100_timer_irq); - local_irq_save(flags); - OIER = OIER_E0; /* enable match on timer 0 to cause interrupts */ - OSMR0 = OSCR + LATCH; /* set initial match */ - local_irq_restore(flags); -} -#ifdef CONFIG_NO_IDLE_HZ -static int sa1100_dyn_tick_enable_disable(void) -{ - /* nothing to do */ - return 0; -} + ckevt_sa1100_osmr0.mult = + div_sc(3686400, NSEC_PER_SEC, ckevt_sa1100_osmr0.shift); + ckevt_sa1100_osmr0.max_delta_ns = + clockevent_delta2ns(0x7fffffff, &ckevt_sa1100_osmr0); + ckevt_sa1100_osmr0.min_delta_ns = + clockevent_delta2ns(MIN_OSCR_DELTA * 2, &ckevt_sa1100_osmr0) + 1; -static void sa1100_dyn_tick_reprogram(unsigned long ticks) -{ - if (ticks > 1) { - initial_match = OSMR0; - OSMR0 = initial_match + ticks * LATCH; - match_posponed = 1; - } -} + cksrc_sa1100_oscr.mult = + clocksource_hz2mult(CLOCK_TICK_RATE, cksrc_sa1100_oscr.shift); -static irqreturn_t -sa1100_dyn_tick_handler(int irq, void *dev_id) -{ - if (match_posponed) { - match_posponed = 0; - OSMR0 = initial_match; - if ((signed long)(initial_match - OSCR) <= 0) - return sa1100_timer_interrupt(irq, dev_id); - } - return IRQ_NONE; -} + setup_irq(IRQ_OST0, &sa1100_timer_irq); -static struct dyn_tick_timer sa1100_dyn_tick = { - .enable = sa1100_dyn_tick_enable_disable, - .disable = sa1100_dyn_tick_enable_disable, - .reprogram = sa1100_dyn_tick_reprogram, - .handler = sa1100_dyn_tick_handler, -}; -#endif + clocksource_register(&cksrc_sa1100_oscr); + clockevents_register_device(&ckevt_sa1100_osmr0); +} #ifdef CONFIG_PM unsigned long osmr[4], oier; @@ -182,8 +155,4 @@ struct sys_timer sa1100_timer = { .init = sa1100_timer_init, .suspend = sa1100_timer_suspend, .resume = sa1100_timer_resume, - .offset = sa1100_gettimeoffset, -#ifdef CONFIG_NO_IDLE_HZ - .dyn_tick = &sa1100_dyn_tick, -#endif };