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/*
* Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include "linux/kernel.h"
#include "linux/module.h"
#include "linux/unistd.h"
#include "linux/stddef.h"
#include "linux/spinlock.h"
#include "linux/time.h"
#include "linux/sched.h"
#include "linux/interrupt.h"
#include "linux/init.h"
#include "linux/delay.h"
#include "asm/irq.h"
#include "asm/param.h"
#include "asm/current.h"
#include "kern_util.h"
#include "user_util.h"
#include "time_user.h"
#include "mode.h"
#include "os.h"
int hz(void)
{
return(HZ);
}
/*
* Scheduler clock - returns current time in nanosec units.
*/
unsigned long long sched_clock(void)
{
return (unsigned long long)jiffies_64 * (1000000000 / HZ);
}
/* Changed at early boot */
int timer_irq_inited = 0;
static int first_tick;
static unsigned long long prev_usecs;
#ifdef CONFIG_UML_REAL_TIME_CLOCK
static long long delta; /* Deviation per interval */
#endif
void timer_irq(union uml_pt_regs *regs)
{
unsigned long long ticks = 0;
if(!timer_irq_inited){
/* This is to ensure that ticks don't pile up when
* the timer handler is suspended */
first_tick = 0;
return;
}
if(first_tick){
#ifdef CONFIG_UML_REAL_TIME_CLOCK
/* We've had 1 tick */
unsigned long long usecs = os_usecs();
delta += usecs - prev_usecs;
prev_usecs = usecs;
/* Protect against the host clock being set backwards */
if(delta < 0)
delta = 0;
ticks += (delta * HZ) / MILLION;
delta -= (ticks * MILLION) / HZ;
#else
ticks = 1;
#endif
}
else {
prev_usecs = os_usecs();
first_tick = 1;
}
while(ticks > 0){
do_IRQ(TIMER_IRQ, regs);
ticks--;
}
}
void boot_timer_handler(int sig)
{
struct pt_regs regs;
CHOOSE_MODE((void)
(UPT_SC(®s.regs) = (struct sigcontext *) (&sig + 1)),
(void) (regs.regs.skas.is_user = 0));
do_timer(®s);
}
irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs)
{
unsigned long flags;
do_timer(regs);
write_seqlock_irqsave(&xtime_lock, flags);
timer();
write_sequnlock_irqrestore(&xtime_lock, flags);
return(IRQ_HANDLED);
}
long um_time(int __user *tloc)
{
struct timeval now;
do_gettimeofday(&now);
if (tloc) {
if (put_user(now.tv_sec, tloc))
now.tv_sec = -EFAULT;
}
return now.tv_sec;
}
long um_stime(int __user *tptr)
{
int value;
struct timespec new;
if (get_user(value, tptr))
return -EFAULT;
new.tv_sec = value;
new.tv_nsec = 0;
do_settimeofday(&new);
return 0;
}
void timer_handler(int sig, union uml_pt_regs *regs)
{
local_irq_disable();
irq_enter();
update_process_times(CHOOSE_MODE(user_context(UPT_SP(regs)),
(regs)->skas.is_user));
irq_exit();
local_irq_enable();
if(current_thread->cpu == 0)
timer_irq(regs);
}
static DEFINE_SPINLOCK(timer_spinlock);
unsigned long time_lock(void)
{
unsigned long flags;
spin_lock_irqsave(&timer_spinlock, flags);
return(flags);
}
void time_unlock(unsigned long flags)
{
spin_unlock_irqrestore(&timer_spinlock, flags);
}
int __init timer_init(void)
{
int err;
user_time_init();
err = request_irq(TIMER_IRQ, um_timer, SA_INTERRUPT, "timer", NULL);
if(err != 0)
printk(KERN_ERR "timer_init : request_irq failed - "
"errno = %d\n", -err);
timer_irq_inited = 1;
return(0);
}
__initcall(timer_init);
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/
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