aboutsummaryrefslogtreecommitdiff
path: root/arch/sh/boards/sh03/rtc.c
blob: 0a9266bb51c58bcd7309dcf15b5870b563a08f11 (plain)
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
132
/*
 * linux/arch/sh/boards/sh03/rtc.c -- CTP/PCI-SH03 on-chip RTC support
 *
 *  Copyright (C) 2004  Saito.K & Jeanne(ksaito@interface.co.jp)
 *
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/bcd.h>
#include <linux/rtc.h>
#include <linux/spinlock.h>
#include <asm/io.h>
#include <asm/rtc.h>

#define RTC_BASE	0xb0000000
#define RTC_SEC1	(RTC_BASE + 0)
#define RTC_SEC10	(RTC_BASE + 1)
#define RTC_MIN1	(RTC_BASE + 2)
#define RTC_MIN10	(RTC_BASE + 3)
#define RTC_HOU1	(RTC_BASE + 4)
#define RTC_HOU10	(RTC_BASE + 5)
#define RTC_WEE1	(RTC_BASE + 6)
#define RTC_DAY1	(RTC_BASE + 7)
#define RTC_DAY10	(RTC_BASE + 8)
#define RTC_MON1	(RTC_BASE + 9)
#define RTC_MON10	(RTC_BASE + 10)
#define RTC_YEA1	(RTC_BASE + 11)
#define RTC_YEA10	(RTC_BASE + 12)
#define RTC_YEA100	(RTC_BASE + 13)
#define RTC_YEA1000	(RTC_BASE + 14)
#define RTC_CTL		(RTC_BASE + 15)
#define RTC_BUSY	1
#define RTC_STOP	2

extern spinlock_t rtc_lock;

unsigned long get_cmos_time(void)
{
	unsigned int year, mon, day, hour, min, sec;

	spin_lock(&rtc_lock);
 again:
	do {
		sec  = (ctrl_inb(RTC_SEC1) & 0xf) + (ctrl_inb(RTC_SEC10) & 0x7) * 10;
		min  = (ctrl_inb(RTC_MIN1) & 0xf) + (ctrl_inb(RTC_MIN10) & 0xf) * 10;
		hour = (ctrl_inb(RTC_HOU1) & 0xf) + (ctrl_inb(RTC_HOU10) & 0xf) * 10;
		day  = (ctrl_inb(RTC_DAY1) & 0xf) + (ctrl_inb(RTC_DAY10) & 0xf) * 10;
		mon  = (ctrl_inb(RTC_MON1) & 0xf) + (ctrl_inb(RTC_MON10) & 0xf) * 10;
		year = (ctrl_inb(RTC_YEA1) & 0xf) + (ctrl_inb(RTC_YEA10) & 0xf) * 10
		     + (ctrl_inb(RTC_YEA100 ) & 0xf) * 100
		     + (ctrl_inb(RTC_YEA1000) & 0xf) * 1000;
	} while (sec != (ctrl_inb(RTC_SEC1) & 0xf) + (ctrl_inb(RTC_SEC10) & 0x7) * 10);
	if (year == 0 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
	    hour > 23 || min > 59 || sec > 59) {
		printk(KERN_ERR
		       "SH-03 RTC: invalid value, resetting to 1 Jan 2000\n");
		printk("year=%d, mon=%d, day=%d, hour=%d, min=%d, sec=%d\n",
		       year, mon, day, hour, min, sec);

		ctrl_outb(0, RTC_SEC1); ctrl_outb(0, RTC_SEC10);
		ctrl_outb(0, RTC_MIN1); ctrl_outb(0, RTC_MIN10);
		ctrl_outb(0, RTC_HOU1); ctrl_outb(0, RTC_HOU10);
		ctrl_outb(6, RTC_WEE1);
		ctrl_outb(1, RTC_DAY1); ctrl_outb(0, RTC_DAY10);
		ctrl_outb(1, RTC_MON1); ctrl_outb(0, RTC_MON10);
		ctrl_outb(0, RTC_YEA1); ctrl_outb(0, RTC_YEA10);
		ctrl_outb(0, RTC_YEA100);
		ctrl_outb(2, RTC_YEA1000);
		ctrl_outb(0, RTC_CTL);
		goto again;
	}

	spin_unlock(&rtc_lock);
	return mktime(year, mon, day, hour, min, sec);
}

void sh03_rtc_gettimeofday(struct timespec *tv)
{

	tv->tv_sec = get_cmos_time();
	tv->tv_nsec = 0;
}

static int set_rtc_mmss(unsigned long nowtime)
{
	int retval = 0;
	int real_seconds, real_minutes, cmos_minutes;
	int i;

	/* gets recalled with irq locally disabled */
	spin_lock(&rtc_lock);
	for (i = 0 ; i < 1000000 ; i++)	/* may take up to 1 second... */
		if (!(ctrl_inb(RTC_CTL) & RTC_BUSY))
			break;
	cmos_minutes = (ctrl_inb(RTC_MIN1) & 0xf) + (ctrl_inb(RTC_MIN10) & 0xf) * 10;
	real_seconds = nowtime % 60;
	real_minutes = nowtime / 60;
	if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
		real_minutes += 30;		/* correct for half hour time zone */
	real_minutes %= 60;

	if (abs(real_minutes - cmos_minutes) < 30) {
		ctrl_outb(real_seconds % 10, RTC_SEC1);
		ctrl_outb(real_seconds / 10, RTC_SEC10);
		ctrl_outb(real_minutes % 10, RTC_MIN1);
		ctrl_outb(real_minutes / 10, RTC_MIN10);
	} else {
		printk(KERN_WARNING
		       "set_rtc_mmss: can't update from %d to %d\n",
		       cmos_minutes, real_minutes);
		retval = -1;
	}
	spin_unlock(&rtc_lock);

	return retval;
}

int sh03_rtc_settimeofday(const time_t secs)
{
	unsigned long nowtime = secs;

	return set_rtc_mmss(nowtime);
}

void sh03_time_init(void)
{
	rtc_sh_get_time = sh03_rtc_gettimeofday;
	rtc_sh_set_time = sh03_rtc_settimeofday;
}