firmware/drivers/rtc/rtc_jz4740.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2008 by Maurus Cuelenaere
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 /*
  23  * Jz OnChip Real Time Clock interface for Linux
  24  *
  25  */
  26
  27 #include "config.h"
  28 #include "jz4740.h"
  29 #include "rtc.h"
  30 #include "timefuncs.h"
  31 #include "logf.h"
  32
  33 static const unsigned int yearday[5] = {0, 366, 366+365, 366+365*2, 366+365*3};
  34 static const unsigned int sweekday = 6;
  35 static const unsigned int sum_monthday[13] = {
  36     0,
  37     31,
  38     31+28,
  39     31+28+31,
  40     31+28+31+30,
  41     31+28+31+30+31,
  42     31+28+31+30+31+30,
  43     31+28+31+30+31+30+31,
  44     31+28+31+30+31+30+31+31,
  45     31+28+31+30+31+30+31+31+30,
  46     31+28+31+30+31+30+31+31+30+31,
  47     31+28+31+30+31+30+31+31+30+31+30,
  48     365
  49 };
  50
  51 static unsigned int jz_mktime(int year, int mon, int day, int hour, int min,
  52                               int sec)
  53 {
  54     unsigned int seccounter;
  55
  56     if (year < 2000)
  57         year = 2000;
  58     year -= 2000;
  59     seccounter = (year/4)*(365*3+366);
  60     seccounter += yearday[year%4];
  61     if (year%4)
  62         seccounter += sum_monthday[mon-1];
  63     else
  64         if (mon >= 3)
  65             seccounter += sum_monthday[mon-1]+1;
  66         else
  67             seccounter += sum_monthday[mon-1];
  68     seccounter += day-1;
  69     seccounter *= 24;
  70     seccounter += hour;
  71     seccounter *= 60;
  72     seccounter += min;
  73     seccounter *= 60;
  74     seccounter += sec;
  75
  76     return seccounter;
  77 }
  78
  79 static void jz_gettime(unsigned int rtc, int *year, int *mon, int *day,
  80                        int *hour, int *min, int *sec, int *weekday)
  81 {
  82     unsigned int tday, tsec, i, tmp;
  83
  84     tday = rtc/(24*3600);
  85     *weekday = ((tday % 7) + sweekday) % 7;
  86     *year = (tday/(366+365*3)) * 4;
  87     tday = tday%(366+365*3);
  88     for (i=0;i<5;i++)
  89     {
  90         if (tday<yearday[i])
  91         {
  92             *year += i-1;
  93             tday -= yearday[i-1];
  94             break;
  95         }
  96     }
  97     for (i=0;i<13;i++)
  98     {
  99         tmp = sum_monthday[i];
 100         if (((*year%4) == 0) && (i>=2))
 101             tmp += 1;
 102         if (tday<tmp)
 103         {
 104             *mon = i;
 105             tmp = sum_monthday[i-1];
 106             if (((*year%4) == 0) && ((i-1)>=2))
 107                 tmp += 1;
 108             *day = tday - tmp + 1;
 109             break;
 110         }
 111     }
 112     tsec = rtc % (24 * 3600);
 113     *hour = tsec / 3600;
 114     *min = (tsec / 60) % 60;
 115     *sec = tsec - *hour*3600 - *min*60;
 116     *year += 2000;
 117 }
 118
 119 int rtc_read_datetime(struct tm *tm)
 120 {
 121     unsigned int sec,mon,mday,wday,year,hour,min;
 122
 123     /*
 124      * Only the values that we read from the RTC are set. We leave
 125      * tm_wday, tm_yday and tm_isdst untouched. Even though the
 126      * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
 127      * by the RTC when initially set to a non-zero value.
 128      */
 129     jz_gettime(REG_RTC_RSR, &year, &mon, &mday, &hour, &min, &sec, &wday);
 130
 131     year -= 2000;
 132
 133     tm->tm_sec = sec;
 134     tm->tm_min = min;
 135     tm->tm_hour = hour;
 136     tm->tm_mday = mday;
 137     tm->tm_wday = wday;
 138     /* Don't use centry, but start from year 1970 */
 139     tm->tm_mon = mon;
 140     if (year <= 69)
 141         year += 100;
 142     tm->tm_year = year;
 143
 144     return 1;
 145 }
 146
 147 int rtc_write_datetime(const struct tm *tm)
 148 {
 149     unsigned int year, lval;
 150
 151     year = tm->tm_year;
 152     /* Don't use centry, but start from year 1970 */
 153     if (year > 69)
 154         year -= 100;
 155     year += 2000;
 156
 157     lval = jz_mktime(year, tm->tm_mon, tm->tm_mday, tm->tm_hour,
 158                      tm->tm_min, tm->tm_sec);
 159
 160     __cpm_start_rtc();
 161     udelay(100);
 162     REG_RTC_RSR = lval;
 163     __cpm_stop_rtc();
 164
 165     return 0;
 166 }
 167
 168 #if 0
 169 void get_rtc_alm_time(struct rtc_time *alm_tm)
 170 {
 171     unsigned int sec,mon,mday,wday,year,hour,min;
 172     unsigned int lval;
 173     unsigned long flags;
 174     /*
 175      * Only the values that we read from the RTC are set. That
 176      * means only tm_hour, tm_min, and tm_sec.
 177      */
 178     lval = REG_RTC_RSAR;
 179     jz_gettime(lval, &year, &mon, &mday, &hour, &min, &sec, &wday);
 180
 181     alm_tm->tm_sec = sec;
 182     alm_tm->tm_min = min;
 183     alm_tm->tm_hour = hour;
 184 }
 185
 186
 187 int rtc_ioctl(unsigned int cmd,struct rtc_time *val,unsigned int epo)
 188 {
 189     struct rtc_time wtime;
 190     switch (cmd) {
 191     case RTC_ALM_READ:    /* Read the present alarm time */
 192         /*
 193          * This returns a struct rtc_time. Reading >= 0xc0
 194          * means "don't care" or "match all". Only the tm_hour,
 195          * tm_min, and tm_sec values are filled in.
 196          */
 197         get_rtc_alm_time(val);
 198         break;
 199     case RTC_ALM_SET:    /* Store a time into the alarm */
 200     {
 201         unsigned char ahrs, amin, asec;
 202         unsigned int sec,mon,mday,wday,year,hour,min;
 203         unsigned int lval;
 204         unsigned long flags;
 205         struct rtc_time alm_tm;
 206
 207         alm_tm = *val;
 208         ahrs = alm_tm.tm_hour;
 209         amin = alm_tm.tm_min;
 210         asec = alm_tm.tm_sec;
 211
 212
 213
 214         if (ahrs >= 24)
 215             return -1;
 216
 217         if (amin >= 60)
 218             return -1;
 219
 220         if (asec >= 60)
 221             return -1;
 222
 223         flags = spin_lock_irqsave();
 224         lval = REG_RTC_RSR;
 225         jz_gettime(lval, &year, &mon, &mday, &hour, &min, &sec, &wday);
 226         hour = ahrs;
 227         min = amin;
 228         sec = asec;
 229         lval = jz_mktime(year, mon, mday, hour, min, sec);
 230         REG_RTC_RSAR = lval;
 231         spin_unlock_irqrestore(flags);
 232         break;
 233     }
 234     case RTC_RD_TIME:    /* Read the time/date from RTC    */
 235         get_rtc_time(val);
 236         break;
 237     case RTC_SET_TIME:    /* Set the RTC */
 238     {
 239         struct rtc_time rtc_tm;
 240         unsigned int mon, day, hrs, min, sec, leap_yr, date;
 241         unsigned int yrs;
 242         unsigned int lval;
 243         unsigned long flags;
 244
 245         rtc_tm = *val;
 246         yrs = rtc_tm.tm_year;// + 1900;
 247         mon = rtc_tm.tm_mon + 1;   /* tm_mon starts at zero */
 248         day = rtc_tm.tm_wday;
 249         date = rtc_tm.tm_mday;
 250         hrs = rtc_tm.tm_hour;
 251         min = rtc_tm.tm_min;
 252         sec = rtc_tm.tm_sec;
 253
 254
 255         if (yrs < 1970)
 256             return -EINVAL;
 257         leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
 258
 259         if ((mon > 12) || (date == 0))
 260             return -EINVAL;
 261
 262         if (date > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
 263             return -EINVAL;
 264
 265         if ((hrs >= 24) || (min >= 60) || (sec >= 60))
 266             return -EINVAL;
 267
 268         if ((yrs -= epoch) > 255)    /* They are unsigned */
 269             return -EINVAL;
 270
 271         flags = spin_lock_irqsave();
 272         /* These limits and adjustments are independant of
 273          * whether the chip is in binary mode or not.
 274          */
 275
 276         if (yrs > 169) {
 277             spin_unlock_irqrestore(flags);
 278             return -EINVAL;
 279         }
 280
 281         yrs += epoch;
 282         lval = jz_mktime(yrs, mon, date, hrs, min, sec);
 283         REG_RTC_RSR = lval;
 284         /* FIXME: maybe we need to write alarm register here. */
 285         spin_unlock_irqrestore(flags);
 286
 287         return 0;
 288     }
 289     break;
 290     case RTC_EPOCH_READ:    /* Read the epoch.    */
 291         epo = epoch;
 292         return 0;
 293     case RTC_EPOCH_SET:    /* Set the epoch.    */
 294         /*
 295          * There were no RTC clocks before 1900.
 296          */
 297         if (epo < 1900)
 298             return -EINVAL;
 299
 300         epoch = epo;
 301         return 0;
 302     default:
 303         return -EINVAL;
 304     }
 305     return -EINVAL;
 306 }
 307 #endif
 308
 309 void rtc_init(void)
 310 {
 311     __cpm_start_rtc();
 312     REG_RTC_RCR = RTC_RCR_RTCE;
 313     udelay(70);
 314     while( !(REG_RTC_RCR & RTC_RCR_WRDY) );
 315     REG_RTC_RGR = (0x7fff | RTC_RGR_LOCK);
 316     udelay(70);
 317     __cpm_stop_rtc();
 318 }