1 /*
2 * linux/arch/sh/boards/sh03/rtc.c -- CTP/PCI-SH03 on-chip RTC support
3 *
4 * Copyright (C) 2004 Saito.K & Jeanne(ksaito@interface.co.jp)
5 *
6 */
7
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/sched.h>
11 #include <linux/time.h>
12 #include <linux/bcd.h>
13 #include <linux/rtc.h>
14 #include <linux/spinlock.h>
15 #include <asm/io.h>
16 #include <asm/rtc.h>
17
18 #define RTC_BASE 0xb0000000
19 #define RTC_SEC1 (RTC_BASE + 0)
20 #define RTC_SEC10 (RTC_BASE + 1)
21 #define RTC_MIN1 (RTC_BASE + 2)
22 #define RTC_MIN10 (RTC_BASE + 3)
23 #define RTC_HOU1 (RTC_BASE + 4)
24 #define RTC_HOU10 (RTC_BASE + 5)
25 #define RTC_WEE1 (RTC_BASE + 6)
26 #define RTC_DAY1 (RTC_BASE + 7)
27 #define RTC_DAY10 (RTC_BASE + 8)
28 #define RTC_MON1 (RTC_BASE + 9)
29 #define RTC_MON10 (RTC_BASE + 10)
30 #define RTC_YEA1 (RTC_BASE + 11)
31 #define RTC_YEA10 (RTC_BASE + 12)
32 #define RTC_YEA100 (RTC_BASE + 13)
33 #define RTC_YEA1000 (RTC_BASE + 14)
34 #define RTC_CTL (RTC_BASE + 15)
35 #define RTC_BUSY 1
36 #define RTC_STOP 2
37
38 static DEFINE_SPINLOCK(sh03_rtc_lock);
39
get_cmos_time(void)40 unsigned long get_cmos_time(void)
41 {
42 unsigned int year, mon, day, hour, min, sec;
43
44 spin_lock(&sh03_rtc_lock);
45 again:
46 do {
47 sec = (__raw_readb(RTC_SEC1) & 0xf) + (__raw_readb(RTC_SEC10) & 0x7) * 10;
48 min = (__raw_readb(RTC_MIN1) & 0xf) + (__raw_readb(RTC_MIN10) & 0xf) * 10;
49 hour = (__raw_readb(RTC_HOU1) & 0xf) + (__raw_readb(RTC_HOU10) & 0xf) * 10;
50 day = (__raw_readb(RTC_DAY1) & 0xf) + (__raw_readb(RTC_DAY10) & 0xf) * 10;
51 mon = (__raw_readb(RTC_MON1) & 0xf) + (__raw_readb(RTC_MON10) & 0xf) * 10;
52 year = (__raw_readb(RTC_YEA1) & 0xf) + (__raw_readb(RTC_YEA10) & 0xf) * 10
53 + (__raw_readb(RTC_YEA100 ) & 0xf) * 100
54 + (__raw_readb(RTC_YEA1000) & 0xf) * 1000;
55 } while (sec != (__raw_readb(RTC_SEC1) & 0xf) + (__raw_readb(RTC_SEC10) & 0x7) * 10);
56 if (year == 0 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
57 hour > 23 || min > 59 || sec > 59) {
58 printk(KERN_ERR
59 "SH-03 RTC: invalid value, resetting to 1 Jan 2000\n");
60 printk("year=%d, mon=%d, day=%d, hour=%d, min=%d, sec=%d\n",
61 year, mon, day, hour, min, sec);
62
63 __raw_writeb(0, RTC_SEC1); __raw_writeb(0, RTC_SEC10);
64 __raw_writeb(0, RTC_MIN1); __raw_writeb(0, RTC_MIN10);
65 __raw_writeb(0, RTC_HOU1); __raw_writeb(0, RTC_HOU10);
66 __raw_writeb(6, RTC_WEE1);
67 __raw_writeb(1, RTC_DAY1); __raw_writeb(0, RTC_DAY10);
68 __raw_writeb(1, RTC_MON1); __raw_writeb(0, RTC_MON10);
69 __raw_writeb(0, RTC_YEA1); __raw_writeb(0, RTC_YEA10);
70 __raw_writeb(0, RTC_YEA100);
71 __raw_writeb(2, RTC_YEA1000);
72 __raw_writeb(0, RTC_CTL);
73 goto again;
74 }
75
76 spin_unlock(&sh03_rtc_lock);
77 return mktime(year, mon, day, hour, min, sec);
78 }
79
sh03_rtc_gettimeofday(struct timespec * tv)80 void sh03_rtc_gettimeofday(struct timespec *tv)
81 {
82
83 tv->tv_sec = get_cmos_time();
84 tv->tv_nsec = 0;
85 }
86
set_rtc_mmss(unsigned long nowtime)87 static int set_rtc_mmss(unsigned long nowtime)
88 {
89 int retval = 0;
90 int real_seconds, real_minutes, cmos_minutes;
91 int i;
92
93 /* gets recalled with irq locally disabled */
94 spin_lock(&sh03_rtc_lock);
95 for (i = 0 ; i < 1000000 ; i++) /* may take up to 1 second... */
96 if (!(__raw_readb(RTC_CTL) & RTC_BUSY))
97 break;
98 cmos_minutes = (__raw_readb(RTC_MIN1) & 0xf) + (__raw_readb(RTC_MIN10) & 0xf) * 10;
99 real_seconds = nowtime % 60;
100 real_minutes = nowtime / 60;
101 if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
102 real_minutes += 30; /* correct for half hour time zone */
103 real_minutes %= 60;
104
105 if (abs(real_minutes - cmos_minutes) < 30) {
106 __raw_writeb(real_seconds % 10, RTC_SEC1);
107 __raw_writeb(real_seconds / 10, RTC_SEC10);
108 __raw_writeb(real_minutes % 10, RTC_MIN1);
109 __raw_writeb(real_minutes / 10, RTC_MIN10);
110 } else {
111 printk_once(KERN_NOTICE
112 "set_rtc_mmss: can't update from %d to %d\n",
113 cmos_minutes, real_minutes);
114 retval = -1;
115 }
116 spin_unlock(&sh03_rtc_lock);
117
118 return retval;
119 }
120
sh03_rtc_settimeofday(const time_t secs)121 int sh03_rtc_settimeofday(const time_t secs)
122 {
123 unsigned long nowtime = secs;
124
125 return set_rtc_mmss(nowtime);
126 }
127
sh03_time_init(void)128 void sh03_time_init(void)
129 {
130 rtc_sh_get_time = sh03_rtc_gettimeofday;
131 rtc_sh_set_time = sh03_rtc_settimeofday;
132 }
133