sys/powerpc/mpc85xx/ds1553_core.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (C) 2006-2008 Semihalf, Grzegorz Bernacki
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  */
  29
  30 #include <sys/cdefs.h>
  31 __FBSDID("$FreeBSD$");
  32
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/bus.h>
  36 #include <sys/clock.h>
  37 #include <sys/lock.h>
  38 #include <sys/mutex.h>
  39
  40 #include <machine/bus.h>
  41
  42 #include <powerpc/mpc85xx/ds1553_reg.h>
  43
  44 static uint8_t ds1553_direct_read(device_t, bus_size_t);
  45 static void ds1553_direct_write(device_t, bus_size_t, uint8_t);
  46
  47 int
  48 ds1553_attach(device_t dev)
  49 {
  50         struct ds1553_softc *sc;
  51         uint8_t sec, flags;
  52
  53         sc = device_get_softc(dev);
  54
  55         if (mtx_initialized(&sc->sc_mtx) == 0) {
  56                 device_printf(dev, "%s: mutex not initialized\n", __func__);
  57                 return (ENXIO);
  58         }
  59
  60         if (sc->sc_read == NULL)
  61                 sc->sc_read = ds1553_direct_read;
  62         if (sc->sc_write == NULL)
  63                 sc->sc_write = ds1553_direct_write;
  64
  65         sc->year_offset = POSIX_BASE_YEAR;
  66
  67         mtx_lock_spin(&sc->sc_mtx);
  68
  69         /* Turn RTC on if it was not on */
  70         sec = (*sc->sc_read)(dev, DS1553_OFF_SECONDS);
  71         if (sec & DS1553_BIT_OSC) {
  72                 sec &= ~(DS1553_BIT_OSC);
  73                 (*sc->sc_write)(dev, DS1553_OFF_SECONDS, sec);
  74         }
  75
  76         /* Low-battery check */
  77         flags = (*sc->sc_read)(dev, DS1553_OFF_FLAGS);
  78         if (flags & DS1553_BIT_BLF)
  79                 device_printf(dev, "voltage-low detected.\n");
  80
  81         mtx_unlock_spin(&sc->sc_mtx);
  82
  83         return (0);
  84 }
  85
  86 /*
  87  * Get time of day and convert it to a struct timespec.
  88  * Return 0 on success, an error number otherwise.
  89  */
  90 int
  91 ds1553_gettime(device_t dev, struct timespec *ts)
  92 {
  93         struct clocktime ct;
  94         struct ds1553_softc *sc;
  95         uint8_t control;
  96
  97         sc = device_get_softc(dev);
  98
  99         mtx_lock_spin(&sc->sc_mtx);
 100
 101         control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_READ;
 102         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 103
 104         ct.nsec = 0;
 105         ct.sec = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_SECONDS) &
 106             DS1553_MASK_SECONDS);
 107         ct.min = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MINUTES) &
 108             DS1553_MASK_MINUTES);
 109         ct.hour = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_HOURS) &
 110             DS1553_MASK_HOUR);
 111         ct.dow = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DAYOFWEEK) &
 112             DS1553_MASK_DAYOFWEEK) - 1;
 113         ct.day = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_DATE) &
 114             DS1553_MASK_DATE);
 115         ct.mon = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_MONTH) &
 116             DS1553_MASK_MONTH);
 117         ct.year = FROMBCD((*sc->sc_read)(dev, DS1553_OFF_YEAR));
 118
 119         control &= ~DS1553_BIT_READ;
 120         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 121
 122         ct.year += sc->year_offset;
 123
 124         mtx_unlock_spin(&sc->sc_mtx);
 125
 126         return (clock_ct_to_ts(&ct, ts));
 127 }
 128
 129 /*
 130  * Set the time of day clock based on the value of the struct timespec arg.
 131  * Return 0 on success, an error number otherwise.
 132  */
 133 int
 134 ds1553_settime(device_t dev, struct timespec *ts)
 135 {
 136         struct clocktime ct;
 137         struct ds1553_softc *sc;
 138         uint8_t control;
 139
 140         sc = device_get_softc(dev);
 141         bzero(&ct, sizeof(struct clocktime));
 142
 143         /* Accuracy is only one second. */
 144         if (ts->tv_nsec >= 500000000)
 145                 ts->tv_sec++;
 146         ts->tv_nsec = 0;
 147         clock_ts_to_ct(ts, &ct);
 148
 149         ct.year -= sc->year_offset;
 150
 151         mtx_lock_spin(&sc->sc_mtx);
 152
 153         /* Halt updates to external registers */
 154         control = (*sc->sc_read)(dev, DS1553_OFF_CONTROL) | DS1553_BIT_WRITE;
 155         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 156
 157         (*sc->sc_write)(dev, DS1553_OFF_SECONDS, TOBCD(ct.sec) &
 158             DS1553_MASK_SECONDS);
 159         (*sc->sc_write)(dev, DS1553_OFF_MINUTES, TOBCD(ct.min) &
 160             DS1553_MASK_MINUTES);
 161         (*sc->sc_write)(dev, DS1553_OFF_HOURS, TOBCD(ct.hour) &
 162             DS1553_MASK_HOUR);
 163         (*sc->sc_write)(dev, DS1553_OFF_DAYOFWEEK, TOBCD(ct.dow + 1) &
 164             DS1553_MASK_DAYOFWEEK);
 165         (*sc->sc_write)(dev, DS1553_OFF_DATE, TOBCD(ct.day) &
 166             DS1553_MASK_DATE);
 167         (*sc->sc_write)(dev, DS1553_OFF_MONTH, TOBCD(ct.mon) &
 168             DS1553_MASK_MONTH);
 169         (*sc->sc_write)(dev, DS1553_OFF_YEAR, TOBCD(ct.year));
 170
 171         /* Resume updates to external registers */
 172         control &= ~DS1553_BIT_WRITE;
 173         (*sc->sc_write)(dev, DS1553_OFF_CONTROL, control);
 174
 175         mtx_unlock_spin(&sc->sc_mtx);
 176
 177         return (0);
 178 }
 179
 180 static uint8_t
 181 ds1553_direct_read(device_t dev, bus_size_t off)
 182 {
 183         struct ds1553_softc *sc;
 184
 185         sc = device_get_softc(dev);
 186         return (bus_space_read_1(sc->sc_bst, sc->sc_bsh, off));
 187 }
 188
 189 static void
 190 ds1553_direct_write(device_t dev, bus_size_t off, uint8_t val)
 191 {
 192         struct ds1553_softc *sc;
 193
 194         sc = device_get_softc(dev);
 195         bus_space_write_1(sc->sc_bst, sc->sc_bsh, off, val);
 196 }