126 lines
2.7 KiB
C
126 lines
2.7 KiB
C
/*
|
|
* 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;
|
|
}
|