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 
35 int have_rtc;  /* used to remember if we have an RTC or not */;
36 
37 #define TICK_SIZE tick
38 
39 extern unsigned long loops_per_jiffy; /* init/main.c */
40 unsigned long loops_per_usec;
41 
42 
43 #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
44 extern unsigned long do_slow_gettimeoffset(void);
45 static unsigned long (*do_gettimeoffset)(void) = do_slow_gettimeoffset;
46 
arch_gettimeoffset(void)47 u32 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 
set_rtc_mmss(unsigned long nowtime)58 int 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_once(KERN_NOTICE
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 
100 unsigned long
get_cmos_time(void)101 get_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 
update_persistent_clock(struct timespec now)128 int update_persistent_clock(struct timespec now)
129 {
130 	return set_rtc_mmss(now.tv_sec);
131 }
132 
read_persistent_clock(struct timespec * ts)133 void read_persistent_clock(struct timespec *ts)
134 {
135 	ts->tv_sec = get_cmos_time();
136 	ts->tv_nsec = 0;
137 }
138 
139 
140 extern void cris_profile_sample(struct pt_regs* regs);
141 
142 void
cris_do_profile(struct pt_regs * regs)143 cris_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 
sched_clock(void)155 unsigned long long sched_clock(void)
156 {
157 	return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ) +
158 		get_ns_in_jiffie();
159 }
160 
161 static int
init_udelay(void)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