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
|
/*
* linux/arch/arm/kernel/time.c
*
* Copyright (C) 1991, 1992, 1995 Linus Torvalds
* Modifications for ARM (C) 1994, 1995, 1996,1997 Russell King
* Copyright (C) 1999 SuSE GmbH, (Philipp Rumpf, prumpf@tux.org)
*
* 1994-07-02 Alan Modra
* fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime
* 1998-12-20 Updated NTP code according to technical memorandum Jan '96
* "A Kernel Model for Precision Timekeeping" by Dave Mills
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/param.h>
#include <asm/pdc.h>
#include <asm/led.h>
#include <linux/timex.h>
extern rwlock_t xtime_lock;
static int timer_value;
static int timer_delta;
static struct pdc_tod tod_data __attribute__((aligned(8)));
void timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
int old;
int lost = 0;
int cr16;
old = timer_value;
cr16 = mfctl(16);
while((timer_value - cr16) < (timer_delta / 2)) {
timer_value += timer_delta;
lost++;
}
mtctl(timer_value ,16);
do_timer(regs);
led_interrupt_func();
}
void do_gettimeofday(struct timeval *tv)
{
unsigned long flags;
read_lock_irqsave(&xtime_lock, flags);
tv->tv_sec = xtime.tv_sec;
tv->tv_usec = xtime.tv_usec;
read_unlock_irqrestore(&xtime_lock, flags);
}
void do_settimeofday(struct timeval *tv)
{
write_lock_irq(&xtime_lock);
xtime.tv_sec = tv->tv_sec;
xtime.tv_usec = tv->tv_usec;
write_unlock_irq(&xtime_lock);
}
void __init time_init(void)
{
timer_delta = (100 * PAGE0->mem_10msec) / HZ;
/* make the first timer interrupt go off in one second */
timer_value = mfctl(16) + (HZ * timer_delta);
mtctl(timer_value, 16);
if(pdc_tod_read(&tod_data) == 0) {
xtime.tv_sec = tod_data.tod_sec;
xtime.tv_usec = tod_data.tod_usec;
} else {
printk(KERN_ERR "Error reading tod clock\n");
xtime.tv_sec = 0;
xtime.tv_usec = 0;
}
}
|
