1 /* $NetBSD: mc146818.c,v 1.18 2008/12/13 17:32:53 tsutsui Exp $ */ 2 3 /*- 4 * Copyright (c) 2003 Izumi Tsutsui. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 /* 28 * mc146818 and compatible time of day chip subroutines 29 */ 30 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: mc146818.c,v 1.18 2008/12/13 17:32:53 tsutsui Exp $"); 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/device.h> 37 #include <sys/errno.h> 38 39 #include <sys/bus.h> 40 41 #include <dev/clock_subr.h> 42 43 #include <dev/ic/mc146818reg.h> 44 #include <dev/ic/mc146818var.h> 45 46 int mc146818_gettime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *); 47 int mc146818_settime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *); 48 49 void 50 mc146818_attach(struct mc146818_softc *sc) 51 { 52 todr_chip_handle_t handle; 53 54 #ifdef DIAGNOSTIC 55 if (sc->sc_mcread == NULL || 56 sc->sc_mcwrite == NULL) 57 panic("%s: invalid read/write functions", __func__); 58 #endif 59 60 aprint_normal(": mc146818 compatible time-of-day clock"); 61 62 handle = &sc->sc_handle; 63 handle->cookie = sc; 64 handle->todr_gettime = NULL; 65 handle->todr_settime = NULL; 66 handle->todr_gettime_ymdhms = mc146818_gettime_ymdhms; 67 handle->todr_settime_ymdhms = mc146818_settime_ymdhms; 68 handle->todr_setwen = NULL; 69 70 todr_attach(handle); 71 } 72 73 /* 74 * todr_gettime function: 75 * Get time of day and convert it to a struct timeval. 76 * Return 0 on success, an error number othersize. 77 */ 78 int 79 mc146818_gettime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt) 80 { 81 struct mc146818_softc *sc; 82 int s, timeout, cent, year; 83 84 sc = handle->cookie; 85 86 s = splclock(); /* XXX really needed? */ 87 88 todr_wenable(handle, 1); 89 90 timeout = 1000000; /* XXX how long should we wait? */ 91 for (;;) { 92 if (((*sc->sc_mcread)(sc, MC_REGA) & MC_REGA_UIP) == 0) 93 break; 94 if (--timeout < 0) { 95 printf("%s: timeout\n", __func__); 96 return EBUSY; 97 } 98 } 99 100 #define FROMREG(x) ((sc->sc_flag & MC146818_BCD) ? FROMBCD(x) : (x)) 101 102 dt->dt_sec = FROMREG((*sc->sc_mcread)(sc, MC_SEC)); 103 dt->dt_min = FROMREG((*sc->sc_mcread)(sc, MC_MIN)); 104 dt->dt_hour = FROMREG((*sc->sc_mcread)(sc, MC_HOUR)); 105 dt->dt_wday = FROMREG((*sc->sc_mcread)(sc, MC_DOW)); 106 dt->dt_day = FROMREG((*sc->sc_mcread)(sc, MC_DOM)); 107 dt->dt_mon = FROMREG((*sc->sc_mcread)(sc, MC_MONTH)); 108 year = FROMREG((*sc->sc_mcread)(sc, MC_YEAR)); 109 if (sc->sc_getcent) { 110 cent = (*sc->sc_getcent)(sc); 111 year += cent * 100; 112 } 113 114 #undef FROMREG 115 116 year += sc->sc_year0; 117 if (year < POSIX_BASE_YEAR && 118 (sc->sc_flag & MC146818_NO_CENT_ADJUST) == 0) 119 year += 100; 120 dt->dt_year = year; 121 122 todr_wenable(handle, 0); 123 124 splx(s); 125 126 return 0; 127 } 128 129 /* 130 * todr_settime function: 131 * Set the time of day clock based on the value of the struct timeval arg. 132 * Return 0 on success, an error number othersize. 133 */ 134 int 135 mc146818_settime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt) 136 { 137 struct mc146818_softc *sc; 138 int s, cent, year; 139 140 sc = handle->cookie; 141 142 s = splclock(); /* XXX really needed? */ 143 144 todr_wenable(handle, 1); 145 146 /* 147 * Disable RTC updates during clock updates 148 */ 149 150 (*sc->sc_mcwrite)(sc, MC_REGB, 151 (*sc->sc_mcread)(sc, MC_REGB) | MC_REGB_SET); 152 153 #define TOREG(x) ((sc->sc_flag & MC146818_BCD) ? TOBCD(x) : (x)) 154 155 (*sc->sc_mcwrite)(sc, MC_SEC, TOREG(dt->dt_sec)); 156 (*sc->sc_mcwrite)(sc, MC_MIN, TOREG(dt->dt_min)); 157 (*sc->sc_mcwrite)(sc, MC_HOUR, TOREG(dt->dt_hour)); 158 (*sc->sc_mcwrite)(sc, MC_DOW, TOREG(dt->dt_wday)); 159 (*sc->sc_mcwrite)(sc, MC_DOM, TOREG(dt->dt_day)); 160 (*sc->sc_mcwrite)(sc, MC_MONTH, TOREG(dt->dt_mon)); 161 162 year = dt->dt_year - sc->sc_year0; 163 if (sc->sc_setcent) { 164 cent = year / 100; 165 (*sc->sc_setcent)(sc, cent); 166 year -= cent * 100; 167 } 168 if (year > 99 && 169 (sc->sc_flag & MC146818_NO_CENT_ADJUST) == 0) 170 year -= 100; 171 (*sc->sc_mcwrite)(sc, MC_YEAR, TOREG(year)); 172 173 #undef TOREG 174 175 /* 176 * Re-enable RTC updates 177 */ 178 179 (*sc->sc_mcwrite)(sc, MC_REGB, 180 (*sc->sc_mcread)(sc, MC_REGB) & ~MC_REGB_SET); 181 182 todr_wenable(handle, 0); 183 184 splx(s); 185 186 return 0; 187 } 188