2 * linux/arch/h8300/kernel/time.c
4 * Yoshinori Sato <ysato@users.sourceforge.jp>
8 * linux/arch/m68k/kernel/time.c
10 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
12 * This file contains the m68k-specific time handling details.
13 * Most of the stuff is located in the machine specific files.
15 * 1997-09-10 Updated NTP code according to technical memorandum Jan '96
16 * "A Kernel Model for Precision Timekeeping" by Dave Mills
19 #include <linux/config.h> /* CONFIG_HEARTBEAT */
20 #include <linux/errno.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/kernel.h>
24 #include <linux/param.h>
25 #include <linux/string.h>
27 #include <linux/timex.h>
28 #include <linux/profile.h>
31 #include <asm/target_time.h>
33 #define TICK_SIZE (tick_nsec / 1000)
37 EXPORT_SYMBOL(jiffies_64);
39 static inline void do_profile (unsigned long pc)
41 if (prof_buffer && current->pid) {
43 pc -= (unsigned long) &_stext;
49 * Don't ignore out-of-bounds PC values silently,
50 * put them into the last histogram slot, so if
51 * present, they will show up as a sharp peak.
53 ++prof_buffer[prof_len-1];
58 * timer_interrupt() needs to keep up the real-time clock,
59 * as well as call the "do_timer()" routine every clocktick
61 static void timer_interrupt(int irq, void *dummy, struct pt_regs * regs)
63 /* may need to kick the hardware timer */
75 unsigned int year, mon, day, hour, min, sec;
77 /* FIX by dqg : Set to zero for platforms that don't have tod */
78 /* without this time is undefined and can overflow time_t, causing */
79 /* very stange errors */
83 platform_gettod (&year, &mon, &day, &hour, &min, &sec);
85 if ((year += 1900) < 1970)
87 xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
90 platform_timer_setup(timer_interrupt);
94 * This version of gettimeofday has near microsecond resolution.
96 void do_gettimeofday(struct timeval *tv)
99 unsigned long usec, sec;
101 read_lock_irqsave(&xtime_lock, flags);
104 usec += (xtime.tv_nsec / 1000);
105 read_unlock_irqrestore(&xtime_lock, flags);
107 while (usec >= 1000000) {
116 EXPORT_SYMBOL(do_gettimeofday);
118 int do_settimeofday(struct timespec *tv)
120 if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
123 write_lock_irq(&xtime_lock);
124 /* This is revolting. We need to set the xtime.tv_usec
125 * correctly. However, the value in this location is
126 * is value at the last tick.
127 * Discover what correction gettimeofday
128 * would have done, and then undo it!
130 while (tv->tv_nsec < 0) {
131 tv->tv_nsec += NSEC_PER_SEC;
135 xtime.tv_sec = tv->tv_sec;
136 xtime.tv_nsec = tv->tv_nsec;
137 time_adjust = 0; /* stop active adjtime() */
138 time_status |= STA_UNSYNC;
139 time_maxerror = NTP_PHASE_LIMIT;
140 time_esterror = NTP_PHASE_LIMIT;
141 write_sequnlock_irq(&xtime_lock);
146 EXPORT_SYMBOL(do_settimeofday);
148 unsigned long long sched_clock(void)
150 return (unsigned long long)jiffies * (1000000000 / HZ);