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/*
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <linux/clockchips.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/threads.h>
#include <asm/irq.h>
#include <asm/param.h>
#include "kern_util.h"
#include "os.h"
/*
* Scheduler clock - returns current time in nanosec units.
*/
unsigned long long sched_clock(void)
{
return (unsigned long long)jiffies_64 * (NSEC_PER_SEC / HZ);
}
void timer_handler(int sig, struct uml_pt_regs *regs)
{
unsigned long flags;
local_irq_save(flags);
do_IRQ(TIMER_IRQ, regs);
local_irq_restore(flags);
}
static void itimer_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
set_interval();
break;
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_ONESHOT:
disable_timer();
break;
case CLOCK_EVT_MODE_RESUME:
break;
}
}
static int itimer_next_event(unsigned long delta,
struct clock_event_device *evt)
{
return timer_one_shot(delta + 1);
}
static struct clock_event_device itimer_clockevent = {
.name = "itimer",
.rating = 250,
.cpumask = CPU_MASK_ALL,
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
.set_mode = itimer_set_mode,
.set_next_event = itimer_next_event,
.shift = 32,
.irq = 0,
};
static irqreturn_t um_timer(int irq, void *dev)
{
(*itimer_clockevent.event_handler)(&itimer_clockevent);
return IRQ_HANDLED;
}
static cycle_t itimer_read(void)
{
return os_nsecs() / 1000;
}
static struct clocksource itimer_clocksource = {
.name = "itimer",
.rating = 300,
.read = itimer_read,
.mask = CLOCKSOURCE_MASK(64),
.mult = 1000,
.shift = 0,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static void __init setup_itimer(void)
{
int err;
err = request_irq(TIMER_IRQ, um_timer, IRQF_DISABLED, "timer", NULL);
if (err != 0)
printk(KERN_ERR "register_timer : request_irq failed - "
"errno = %d\n", -err);
itimer_clockevent.mult = div_sc(HZ, NSEC_PER_SEC, 32);
itimer_clockevent.max_delta_ns =
clockevent_delta2ns(60 * HZ, &itimer_clockevent);
itimer_clockevent.min_delta_ns =
clockevent_delta2ns(1, &itimer_clockevent);
err = clocksource_register(&itimer_clocksource);
if (err) {
printk(KERN_ERR "clocksource_register returned %d\n", err);
return;
}
clockevents_register_device(&itimer_clockevent);
}
void __init time_init(void)
{
long long nsecs;
timer_init();
nsecs = os_nsecs();
set_normalized_timespec(&wall_to_monotonic, -nsecs / NSEC_PER_SEC,
-nsecs % NSEC_PER_SEC);
set_normalized_timespec(&xtime, nsecs / NSEC_PER_SEC,
nsecs % NSEC_PER_SEC);
late_time_init = setup_itimer;
}
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