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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/arch/cris/kernel/
1/*
2 *  linux/arch/cris/kernel/time.c
3 *
4 *  Copyright (C) 1991, 1992, 1995  Linus Torvalds
5 *  Copyright (C) 1999, 2000, 2001 Axis Communications AB
6 *
7 * 1994-07-02    Alan Modra
8 *	fixed set_rtc_mmss, fixed time.year for >= 2000, new mktime
9 * 1995-03-26    Markus Kuhn
10 *      fixed 500 ms bug at call to set_rtc_mmss, fixed DS12887
11 *      precision CMOS clock update
12 * 1996-05-03    Ingo Molnar
13 *      fixed time warps in do_[slow|fast]_gettimeoffset()
14 * 1997-09-10	Updated NTP code according to technical memorandum Jan '96
15 *		"A Kernel Model for Precision Timekeeping" by Dave Mills
16 *
17 * Linux/CRIS specific code:
18 *
19 * Authors:    Bjorn Wesen
20 *             Johan Adolfsson
21 *
22 */
23
24#include <asm/rtc.h>
25#include <linux/errno.h>
26#include <linux/module.h>
27#include <linux/param.h>
28#include <linux/jiffies.h>
29#include <linux/bcd.h>
30#include <linux/timex.h>
31#include <linux/init.h>
32#include <linux/profile.h>
33#include <linux/sched.h>	/* just for sched_clock() - funny that */
34
35int have_rtc;  /* used to remember if we have an RTC or not */;
36
37#define TICK_SIZE tick
38
39extern unsigned long loops_per_jiffy; /* init/main.c */
40unsigned long loops_per_usec;
41
42
43#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
44extern unsigned long do_slow_gettimeoffset(void);
45static unsigned long (*do_gettimeoffset)(void) = do_slow_gettimeoffset;
46
47u32 arch_gettimeoffset(void)
48{
49       return do_gettimeoffset() * 1000;
50}
51#endif
52
53/*
54 * BUG: This routine does not handle hour overflow properly; it just
55 *      sets the minutes. Usually you'll only notice that after reboot!
56 */
57
58int set_rtc_mmss(unsigned long nowtime)
59{
60	int retval = 0;
61	int real_seconds, real_minutes, cmos_minutes;
62
63	printk(KERN_DEBUG "set_rtc_mmss(%lu)\n", nowtime);
64
65	if(!have_rtc)
66		return 0;
67
68	cmos_minutes = CMOS_READ(RTC_MINUTES);
69	cmos_minutes = bcd2bin(cmos_minutes);
70
71	/*
72	 * since we're only adjusting minutes and seconds,
73	 * don't interfere with hour overflow. This avoids
74	 * messing with unknown time zones but requires your
75	 * RTC not to be off by more than 15 minutes
76	 */
77	real_seconds = nowtime % 60;
78	real_minutes = nowtime / 60;
79	if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
80		real_minutes += 30;		/* correct for half hour time zone */
81	real_minutes %= 60;
82
83	if (abs(real_minutes - cmos_minutes) < 30) {
84		real_seconds = bin2bcd(real_seconds);
85		real_minutes = bin2bcd(real_minutes);
86		CMOS_WRITE(real_seconds,RTC_SECONDS);
87		CMOS_WRITE(real_minutes,RTC_MINUTES);
88	} else {
89		printk(KERN_WARNING
90		       "set_rtc_mmss: can't update from %d to %d\n",
91		       cmos_minutes, real_minutes);
92		retval = -1;
93	}
94
95	return retval;
96}
97
98/* grab the time from the RTC chip */
99
100unsigned long
101get_cmos_time(void)
102{
103	unsigned int year, mon, day, hour, min, sec;
104	if(!have_rtc)
105		return 0;
106
107	sec = CMOS_READ(RTC_SECONDS);
108	min = CMOS_READ(RTC_MINUTES);
109	hour = CMOS_READ(RTC_HOURS);
110	day = CMOS_READ(RTC_DAY_OF_MONTH);
111	mon = CMOS_READ(RTC_MONTH);
112	year = CMOS_READ(RTC_YEAR);
113
114	sec = bcd2bin(sec);
115	min = bcd2bin(min);
116	hour = bcd2bin(hour);
117	day = bcd2bin(day);
118	mon = bcd2bin(mon);
119	year = bcd2bin(year);
120
121	if ((year += 1900) < 1970)
122		year += 100;
123
124	return mktime(year, mon, day, hour, min, sec);
125}
126
127
128int update_persistent_clock(struct timespec now)
129{
130	return set_rtc_mmss(now.tv_sec);
131}
132
133void read_persistent_clock(struct timespec *ts)
134{
135	ts->tv_sec = get_cmos_time();
136	ts->tv_nsec = 0;
137}
138
139
140extern void cris_profile_sample(struct pt_regs* regs);
141
142void
143cris_do_profile(struct pt_regs* regs)
144{
145
146#ifdef CONFIG_SYSTEM_PROFILER
147        cris_profile_sample(regs);
148#endif
149
150#ifdef CONFIG_PROFILING
151	profile_tick(CPU_PROFILING);
152#endif
153}
154
155unsigned long long sched_clock(void)
156{
157	return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ) +
158		get_ns_in_jiffie();
159}
160
161static int
162__init init_udelay(void)
163{
164	loops_per_usec = (loops_per_jiffy * HZ) / 1000000;
165	return 0;
166}
167
168__initcall(init_udelay);
169