2 * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
6 #include "linux/kernel.h"
7 #include "linux/module.h"
8 #include "linux/unistd.h"
9 #include "linux/stddef.h"
10 #include "linux/spinlock.h"
11 #include "linux/time.h"
12 #include "linux/sched.h"
13 #include "linux/interrupt.h"
14 #include "linux/init.h"
15 #include "linux/delay.h"
17 #include "asm/param.h"
18 #include "asm/current.h"
19 #include "kern_util.h"
20 #include "user_util.h"
21 #include "time_user.h"
25 u64 jiffies_64 = INITIAL_JIFFIES;
27 EXPORT_SYMBOL(jiffies_64);
35 * Scheduler clock - returns current time in nanosec units.
37 unsigned long long sched_clock(void)
39 return (unsigned long long)jiffies_64 * (1000000000 / HZ);
42 /* Changed at early boot */
43 int timer_irq_inited = 0;
45 static int first_tick;
46 static unsigned long long prev_usecs;
47 #ifdef CONFIG_UML_REAL_TIME_CLOCK
48 static long long delta; /* Deviation per interval */
51 #define MILLION 1000000
53 void timer_irq(union uml_pt_regs *regs)
55 unsigned long long ticks = 0;
57 if(!timer_irq_inited){
58 /* This is to ensure that ticks don't pile up when
59 * the timer handler is suspended */
65 #ifdef CONFIG_UML_REAL_TIME_CLOCK
66 /* We've had 1 tick */
67 unsigned long long usecs = os_usecs();
69 delta += usecs - prev_usecs;
72 /* Protect against the host clock being set backwards */
76 ticks += (delta * HZ) / MILLION;
77 delta -= (ticks * MILLION) / HZ;
83 prev_usecs = os_usecs();
88 do_IRQ(TIMER_IRQ, regs);
93 void boot_timer_handler(int sig)
98 (UPT_SC(®s.regs) = (struct sigcontext *) (&sig + 1)),
99 (void) (regs.regs.skas.is_user = 0));
103 irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs)
108 write_seqlock_irqsave(&xtime_lock, flags);
110 write_sequnlock_irqrestore(&xtime_lock, flags);
114 long um_time(int __user *tloc)
118 do_gettimeofday(&now);
120 if (put_user(now.tv_sec, tloc))
121 now.tv_sec = -EFAULT;
126 long um_stime(int __user *tptr)
131 if (get_user(value, tptr))
135 do_settimeofday(&new);
139 void __udelay(unsigned long usecs)
143 n = (loops_per_jiffy * HZ * usecs) / MILLION;
147 void __const_udelay(unsigned long usecs)
151 n = (loops_per_jiffy * HZ * usecs) / MILLION;
155 void timer_handler(int sig, union uml_pt_regs *regs)
158 update_process_times(CHOOSE_MODE(user_context(UPT_SP(regs)), (regs)->skas.is_user));
160 if(current_thread->cpu == 0)
164 static DEFINE_SPINLOCK(timer_spinlock);
166 unsigned long time_lock(void)
170 spin_lock_irqsave(&timer_spinlock, flags);
174 void time_unlock(unsigned long flags)
176 spin_unlock_irqrestore(&timer_spinlock, flags);
179 int __init timer_init(void)
183 CHOOSE_MODE(user_time_init_tt(), user_time_init_skas());
184 err = request_irq(TIMER_IRQ, um_timer, SA_INTERRUPT, "timer", NULL);
186 printk(KERN_ERR "timer_init : request_irq failed - "
187 "errno = %d\n", -err);
188 timer_irq_inited = 1;
192 __initcall(timer_init);
195 * Overrides for Emacs so that we follow Linus's tabbing style.
196 * Emacs will notice this stuff at the end of the file and automatically
197 * adjust the settings for this buffer only. This must remain at the end
199 * ---------------------------------------------------------------------------
201 * c-file-style: "linux"