arch/sh/boards/sh03/rtc.c

   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 <asm/io.h>
  13 #include <linux/rtc.h>
  14 #include <linux/spinlock.h>
  15
  16 #define RTC_BASE        0xb0000000
  17 #define RTC_SEC1        (RTC_BASE + 0)
  18 #define RTC_SEC10       (RTC_BASE + 1)
  19 #define RTC_MIN1        (RTC_BASE + 2)
  20 #define RTC_MIN10       (RTC_BASE + 3)
  21 #define RTC_HOU1        (RTC_BASE + 4)
  22 #define RTC_HOU10       (RTC_BASE + 5)
  23 #define RTC_WEE1        (RTC_BASE + 6)
  24 #define RTC_DAY1        (RTC_BASE + 7)
  25 #define RTC_DAY10       (RTC_BASE + 8)
  26 #define RTC_MON1        (RTC_BASE + 9)
  27 #define RTC_MON10       (RTC_BASE + 10)
  28 #define RTC_YEA1        (RTC_BASE + 11)
  29 #define RTC_YEA10       (RTC_BASE + 12)
  30 #define RTC_YEA100      (RTC_BASE + 13)
  31 #define RTC_YEA1000     (RTC_BASE + 14)
  32 #define RTC_CTL         (RTC_BASE + 15)
  33 #define RTC_BUSY        1
  34 #define RTC_STOP        2
  35
  36 #ifndef BCD_TO_BIN
  37 #define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10)
  38 #endif
  39
  40 #ifndef BIN_TO_BCD
  41 #define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10)
  42 #endif
  43
  44 extern void (*rtc_get_time)(struct timespec *);
  45 extern int (*rtc_set_time)(const time_t);
  46 extern spinlock_t rtc_lock;
  47
  48 unsigned long get_cmos_time(void)
  49 {
  50         unsigned int year, mon, day, hour, min, sec;
  51         int i;
  52
  53         spin_lock(&rtc_lock);
  54  again:
  55         for (i = 0 ; i < 1000000 ; i++) /* may take up to 1 second... */
  56                 if (!(ctrl_inb(RTC_CTL) & RTC_BUSY))
  57                         break;
  58         do {
  59                 sec  = (ctrl_inb(RTC_SEC1) & 0xf) + (ctrl_inb(RTC_SEC10) & 0x7) * 10;
  60                 min  = (ctrl_inb(RTC_MIN1) & 0xf) + (ctrl_inb(RTC_MIN10) & 0xf) * 10;
  61                 hour = (ctrl_inb(RTC_HOU1) & 0xf) + (ctrl_inb(RTC_HOU10) & 0xf) * 10;
  62                 day  = (ctrl_inb(RTC_DAY1) & 0xf) + (ctrl_inb(RTC_DAY10) & 0xf) * 10;
  63                 mon  = (ctrl_inb(RTC_MON1) & 0xf) + (ctrl_inb(RTC_MON10) & 0xf) * 10;
  64                 year = (ctrl_inb(RTC_YEA1) & 0xf) + (ctrl_inb(RTC_YEA10) & 0xf) * 10
  65                      + (ctrl_inb(RTC_YEA100 ) & 0xf) * 100
  66                      + (ctrl_inb(RTC_YEA1000) & 0xf) * 1000;
  67         } while (sec != (ctrl_inb(RTC_SEC1) & 0xf) + (ctrl_inb(RTC_SEC10) & 0x7) * 10);
  68         if (year == 0 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
  69             hour > 23 || min > 59 || sec > 59) {
  70                 printk(KERN_ERR
  71                        "SH-03 RTC: invalid value, resetting to 1 Jan 2000\n");
  72                 printk("year=%d, mon=%d, day=%d, hour=%d, min=%d, sec=%d\n",
  73                        year, mon, day, hour, min, sec);
  74
  75                 ctrl_outb(0, RTC_SEC1); ctrl_outb(0, RTC_SEC10);
  76                 ctrl_outb(0, RTC_MIN1); ctrl_outb(0, RTC_MIN10);
  77                 ctrl_outb(0, RTC_HOU1); ctrl_outb(0, RTC_HOU10);
  78                 ctrl_outb(6, RTC_WEE1);
  79                 ctrl_outb(1, RTC_DAY1); ctrl_outb(0, RTC_DAY10);
  80                 ctrl_outb(1, RTC_MON1); ctrl_outb(0, RTC_MON10);
  81                 ctrl_outb(0, RTC_YEA1); ctrl_outb(0, RTC_YEA10);
  82                 ctrl_outb(0, RTC_YEA100);
  83                 ctrl_outb(2, RTC_YEA1000);
  84                 ctrl_outb(0, RTC_CTL);
  85                 goto again;
  86         }
  87
  88         spin_unlock(&rtc_lock);
  89         return mktime(year, mon, day, hour, min, sec);
  90 }
  91
  92 void sh03_rtc_gettimeofday(struct timespec *tv)
  93 {
  94
  95         tv->tv_sec = get_cmos_time();
  96         tv->tv_nsec = 0;
  97 }
  98
  99 static int set_rtc_mmss(unsigned long nowtime)
 100 {
 101         int retval = 0;
 102         int real_seconds, real_minutes, cmos_minutes;
 103         int i;
 104
 105         /* gets recalled with irq locally disabled */
 106         spin_lock(&rtc_lock);
 107         for (i = 0 ; i < 1000000 ; i++) /* may take up to 1 second... */
 108                 if (!(ctrl_inb(RTC_CTL) & RTC_BUSY))
 109                         break;
 110         cmos_minutes = (ctrl_inb(RTC_MIN1) & 0xf) + (ctrl_inb(RTC_MIN10) & 0xf) * 10;
 111         real_seconds = nowtime % 60;
 112         real_minutes = nowtime / 60;
 113         if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
 114                 real_minutes += 30;             /* correct for half hour time zone */
 115         real_minutes %= 60;
 116
 117         if (abs(real_minutes - cmos_minutes) < 30) {
 118                 ctrl_outb(real_seconds % 10, RTC_SEC1);
 119                 ctrl_outb(real_seconds / 10, RTC_SEC10);
 120                 ctrl_outb(real_minutes % 10, RTC_MIN1);
 121                 ctrl_outb(real_minutes / 10, RTC_MIN10);
 122         } else {
 123                 printk(KERN_WARNING
 124                        "set_rtc_mmss: can't update from %d to %d\n",
 125                        cmos_minutes, real_minutes);
 126                 retval = -1;
 127         }
 128         spin_unlock(&rtc_lock);
 129
 130         return retval;
 131 }
 132
 133 int sh03_rtc_settimeofday(const time_t secs)
 134 {
 135         unsigned long nowtime = secs;
 136
 137         return set_rtc_mmss(nowtime);
 138 }
 139
 140 void sh03_time_init(void)
 141 {
 142         rtc_get_time = sh03_rtc_gettimeofday;
 143         rtc_set_time = sh03_rtc_settimeofday;
 144 }