127 lines
2.7 KiB
C
127 lines
2.7 KiB
C
/*
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* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
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* Licensed under the GPL
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*/
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#include "linux/clockchips.h"
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#include "linux/interrupt.h"
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#include "linux/jiffies.h"
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#include "linux/threads.h"
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#include "asm/irq.h"
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#include "asm/param.h"
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#include "kern_util.h"
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#include "os.h"
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/*
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* Scheduler clock - returns current time in nanosec units.
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*/
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unsigned long long sched_clock(void)
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{
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return (unsigned long long)jiffies_64 * (NSEC_PER_SEC / HZ);
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}
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void timer_handler(int sig, struct uml_pt_regs *regs)
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{
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unsigned long flags;
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local_irq_save(flags);
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do_IRQ(TIMER_IRQ, regs);
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local_irq_restore(flags);
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}
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static void itimer_set_mode(enum clock_event_mode mode,
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struct clock_event_device *evt)
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{
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switch(mode) {
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case CLOCK_EVT_MODE_PERIODIC:
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set_interval();
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break;
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case CLOCK_EVT_MODE_SHUTDOWN:
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case CLOCK_EVT_MODE_UNUSED:
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case CLOCK_EVT_MODE_ONESHOT:
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disable_timer();
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break;
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case CLOCK_EVT_MODE_RESUME:
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break;
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}
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}
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static int itimer_next_event(unsigned long delta,
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struct clock_event_device *evt)
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{
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return timer_one_shot(delta + 1);
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}
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static struct clock_event_device itimer_clockevent = {
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.name = "itimer",
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.rating = 250,
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.cpumask = CPU_MASK_ALL,
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.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
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.set_mode = itimer_set_mode,
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.set_next_event = itimer_next_event,
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.shift = 32,
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.irq = 0,
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};
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static irqreturn_t um_timer(int irq, void *dev)
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{
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(*itimer_clockevent.event_handler)(&itimer_clockevent);
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return IRQ_HANDLED;
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}
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static cycle_t itimer_read(void)
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{
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return os_nsecs();
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}
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static struct clocksource itimer_clocksource = {
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.name = "itimer",
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.rating = 300,
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.read = itimer_read,
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.mask = CLOCKSOURCE_MASK(64),
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.mult = 1,
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.shift = 0,
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.flags = CLOCK_SOURCE_IS_CONTINUOUS,
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};
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static void __init setup_itimer(void)
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{
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int err;
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err = request_irq(TIMER_IRQ, um_timer, IRQF_DISABLED, "timer", NULL);
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if (err != 0)
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printk(KERN_ERR "register_timer : request_irq failed - "
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"errno = %d\n", -err);
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itimer_clockevent.mult = div_sc(HZ, NSEC_PER_SEC, 32);
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itimer_clockevent.max_delta_ns =
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clockevent_delta2ns(60 * HZ, &itimer_clockevent);
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itimer_clockevent.min_delta_ns =
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clockevent_delta2ns(1, &itimer_clockevent);
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err = clocksource_register(&itimer_clocksource);
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if (err) {
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printk(KERN_ERR "clocksource_register returned %d\n", err);
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return;
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}
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clockevents_register_device(&itimer_clockevent);
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}
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extern void (*late_time_init)(void);
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void __init time_init(void)
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{
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long long nsecs;
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timer_init();
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nsecs = os_nsecs();
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set_normalized_timespec(&wall_to_monotonic, -nsecs / NSEC_PER_SEC,
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-nsecs % NSEC_PER_SEC);
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set_normalized_timespec(&xtime, nsecs / NSEC_PER_SEC,
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nsecs % NSEC_PER_SEC);
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late_time_init = setup_itimer;
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}
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