1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
/*
* linux/arch/h8300/kernel/time.c
*
* Yoshinori Sato <ysato@users.sourceforge.jp>
*
* Copied/hacked from:
*
* linux/arch/m68k/kernel/time.c
*
* Copyright (C) 1991, 1992, 1995 Linus Torvalds
*
* This file contains the m68k-specific time handling details.
* Most of the stuff is located in the machine specific files.
*
* 1997-09-10 Updated NTP code according to technical memorandum Jan '96
* "A Kernel Model for Precision Timekeeping" by Dave Mills
*/
#include <linux/config.h> /* CONFIG_HEARTBEAT */
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/timex.h>
#include <linux/profile.h>
#include <asm/io.h>
#include <asm/target_time.h>
#define TICK_SIZE (tick_nsec / 1000)
u64 jiffies_64;
EXPORT_SYMBOL(jiffies_64);
/*
* timer_interrupt() needs to keep up the real-time clock,
* as well as call the "do_timer()" routine every clocktick
*/
static void timer_interrupt(int irq, void *dummy, struct pt_regs * regs)
{
/* may need to kick the hardware timer */
platform_timer_eoi();
do_timer(regs);
#ifndef CONFIG_SMP
update_process_times(user_mode(regs));
#endif
profile_tick(CPU_PROFILING, regs);
}
void time_init(void)
{
unsigned int year, mon, day, hour, min, sec;
/* FIX by dqg : Set to zero for platforms that don't have tod */
/* without this time is undefined and can overflow time_t, causing */
/* very stange errors */
year = 1980;
mon = day = 1;
hour = min = sec = 0;
platform_gettod (&year, &mon, &day, &hour, &min, &sec);
if ((year += 1900) < 1970)
year += 100;
xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
xtime.tv_nsec = 0;
platform_timer_setup(timer_interrupt);
}
/*
* This version of gettimeofday has near microsecond resolution.
*/
void do_gettimeofday(struct timeval *tv)
{
unsigned long flags;
unsigned long usec, sec;
read_lock_irqsave(&xtime_lock, flags);
usec = 0;
sec = xtime.tv_sec;
usec += (xtime.tv_nsec / 1000);
read_unlock_irqrestore(&xtime_lock, flags);
while (usec >= 1000000) {
usec -= 1000000;
sec++;
}
tv->tv_sec = sec;
tv->tv_usec = usec;
}
EXPORT_SYMBOL(do_gettimeofday);
int do_settimeofday(struct timespec *tv)
{
if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
write_lock_irq(&xtime_lock);
/* This is revolting. We need to set the xtime.tv_usec
* correctly. However, the value in this location is
* is value at the last tick.
* Discover what correction gettimeofday
* would have done, and then undo it!
*/
while (tv->tv_nsec < 0) {
tv->tv_nsec += NSEC_PER_SEC;
tv->tv_sec--;
}
xtime.tv_sec = tv->tv_sec;
xtime.tv_nsec = tv->tv_nsec;
ntp_clear();
write_sequnlock_irq(&xtime_lock);
clock_was_set();
return 0;
}
EXPORT_SYMBOL(do_settimeofday);
unsigned long long sched_clock(void)
{
return (unsigned long long)jiffies * (1000000000 / HZ);
}
|
