diff options
Diffstat (limited to 'arch/arm/mach-sa1100/time.c')
| -rw-r--r-- | arch/arm/mach-sa1100/time.c | 153 |
1 files changed, 67 insertions, 86 deletions
diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c index a9799cb35b7..1dea6cfafb3 100644 --- a/arch/arm/mach-sa1100/time.c +++ b/arch/arm/mach-sa1100/time.c @@ -2,21 +2,32 @@ * linux/arch/arm/mach-sa1100/time.c * * Copyright (C) 1998 Deborah Wallach. - * Twiddles (C) 1999 Hugo Fiennes <hugo@empeg.com> - * - * 2000/03/29 (C) Nicolas Pitre <nico@cam.org> + * Twiddles (C) 1999 Hugo Fiennes <hugo@empeg.com> + * + * 2000/03/29 (C) Nicolas Pitre <nico@fluxnic.net> * Rewritten: big cleanup, much simpler, better HZ accuracy. * */ #include <linux/init.h> +#include <linux/kernel.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/timex.h> #include <linux/clockchips.h> +#include <linux/sched_clock.h> #include <asm/mach/time.h> -#include <asm/hardware.h> +#include <mach/hardware.h> +#include <mach/irqs.h> + +#define SA1100_CLOCK_FREQ 3686400 +#define SA1100_LATCH DIV_ROUND_CLOSEST(SA1100_CLOCK_FREQ, HZ) + +static u64 notrace sa1100_read_sched_clock(void) +{ + return readl_relaxed(OSCR); +} #define MIN_OSCR_DELTA 2 @@ -25,8 +36,8 @@ static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id) struct clock_event_device *c = dev_id; /* Disarm the compare/match, signal the event. */ - OIER &= ~OIER_E0; - OSSR = OSSR_M0; + writel_relaxed(readl_relaxed(OIER) & ~OIER_E0, OIER); + writel_relaxed(OSSR_M0, OSSR); c->event_handler(c); return IRQ_HANDLED; @@ -35,14 +46,12 @@ static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id) static int sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c) { - unsigned long flags, next, oscr; + unsigned long next, oscr; - raw_local_irq_save(flags); - OIER |= OIER_E0; - next = OSCR + delta; - OSMR0 = next; - oscr = OSCR; - raw_local_irq_restore(flags); + writel_relaxed(readl_relaxed(OIER) | OIER_E0, OIER); + next = readl_relaxed(OSCR) + delta; + writel_relaxed(next, OSMR0); + oscr = readl_relaxed(OSCR); return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0; } @@ -50,16 +59,12 @@ sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c) static void sa1100_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *c) { - unsigned long flags; - 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); + writel_relaxed(readl_relaxed(OIER) & ~OIER_E0, OIER); + writel_relaxed(OSSR_M0, OSSR); break; case CLOCK_EVT_MODE_RESUME: @@ -68,91 +73,67 @@ sa1100_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *c) } } +#ifdef CONFIG_PM +unsigned long osmr[4], oier; + +static void sa1100_timer_suspend(struct clock_event_device *cedev) +{ + osmr[0] = readl_relaxed(OSMR0); + osmr[1] = readl_relaxed(OSMR1); + osmr[2] = readl_relaxed(OSMR2); + osmr[3] = readl_relaxed(OSMR3); + oier = readl_relaxed(OIER); +} + +static void sa1100_timer_resume(struct clock_event_device *cedev) +{ + writel_relaxed(0x0f, OSSR); + writel_relaxed(osmr[0], OSMR0); + writel_relaxed(osmr[1], OSMR1); + writel_relaxed(osmr[2], OSMR2); + writel_relaxed(osmr[3], OSMR3); + writel_relaxed(oier, OIER); + + /* + * OSMR0 is the system timer: make sure OSCR is sufficiently behind + */ + writel_relaxed(OSMR0 - SA1100_LATCH, OSCR); +} +#else +#define sa1100_timer_suspend NULL +#define sa1100_timer_resume NULL +#endif + 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, -}; - -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, + .suspend = sa1100_timer_suspend, + .resume = sa1100_timer_resume, }; static struct irqaction sa1100_timer_irq = { .name = "ost0", - .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, + .flags = IRQF_TIMER | IRQF_IRQPOLL, .handler = sa1100_ost0_interrupt, .dev_id = &ckevt_sa1100_osmr0, }; -static void __init sa1100_timer_init(void) +void __init sa1100_timer_init(void) { - OIER = 0; /* disable any timer interrupts */ - OSSR = 0xf; /* clear status on all timers */ + writel_relaxed(0, OIER); + writel_relaxed(OSSR_M0 | OSSR_M1 | OSSR_M2 | OSSR_M3, OSSR); - 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; + sched_clock_register(sa1100_read_sched_clock, 32, 3686400); - cksrc_sa1100_oscr.mult = - clocksource_hz2mult(CLOCK_TICK_RATE, cksrc_sa1100_oscr.shift); + ckevt_sa1100_osmr0.cpumask = cpumask_of(0); setup_irq(IRQ_OST0, &sa1100_timer_irq); - clocksource_register(&cksrc_sa1100_oscr); - clockevents_register_device(&ckevt_sa1100_osmr0); -} - -#ifdef CONFIG_PM -unsigned long osmr[4], oier; - -static void sa1100_timer_suspend(void) -{ - osmr[0] = OSMR0; - osmr[1] = OSMR1; - osmr[2] = OSMR2; - osmr[3] = OSMR3; - oier = OIER; -} - -static void sa1100_timer_resume(void) -{ - OSSR = 0x0f; - 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; + clocksource_mmio_init(OSCR, "oscr", SA1100_CLOCK_FREQ, 200, 32, + clocksource_mmio_readl_up); + clockevents_config_and_register(&ckevt_sa1100_osmr0, 3686400, + MIN_OSCR_DELTA * 2, 0x7fffffff); } -#else -#define sa1100_timer_suspend NULL -#define sa1100_timer_resume NULL -#endif - -struct sys_timer sa1100_timer = { - .init = sa1100_timer_init, - .suspend = sa1100_timer_suspend, - .resume = sa1100_timer_resume, -}; |