rtc.c revision 1.22
1 /* $NetBSD: rtc.c,v 1.22 2025/09/07 04:47:00 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 2001 Valeriy E. Ushakov 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 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 /* 31 * `rtc' is a DS1287A (== MC146818A) time-of-day clock at EBus. 32 * In Krups it's not used to store idprom so this driver doesn't 33 * support it. Don't know about other ms-IIep systems. 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: rtc.c,v 1.22 2025/09/07 04:47:00 thorpej Exp $"); 38 39 #include <sys/param.h> 40 #include <sys/kernel.h> 41 #include <sys/device.h> 42 #include <sys/systm.h> 43 #ifdef GPROF 44 #include <sys/gmon.h> 45 #endif 46 47 #include <sys/bus.h> 48 #include <machine/autoconf.h> 49 50 #include <dev/clock_subr.h> 51 #include <dev/ic/mc146818reg.h> 52 53 #include <dev/ebus/ebusreg.h> 54 #include <dev/ebus/ebusvar.h> 55 56 struct rtc_ebus_softc { 57 bus_space_tag_t sc_bt; /* parent bus tag */ 58 bus_space_handle_t sc_bh; /* handle for registers */ 59 struct todr_chip_handle sc_todr;/* TODR handle */ 60 }; 61 62 static int rtcmatch_ebus(device_t, cfdata_t, void *); 63 static void rtcattach_ebus(device_t, device_t, void *); 64 65 CFATTACH_DECL_NEW(rtc_ebus, sizeof(struct rtc_ebus_softc), 66 rtcmatch_ebus, rtcattach_ebus, NULL, NULL); 67 68 /* todr(9) methods */ 69 static int rtc_gettime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *); 70 static int rtc_settime_ymdhms(todr_chip_handle_t, struct clock_ymdhms *); 71 72 int rtc_auto_century_adjust = 1; /* XXX: do we ever want not to? */ 73 74 /* 75 * MD read/write functions declared in mc146818reg.h 76 */ 77 #define RTC_ADDR 0 78 #define RTC_DATA 1 79 80 u_int 81 mc146818_read(void *cookie, u_int reg) 82 { 83 struct rtc_ebus_softc *sc = cookie; 84 85 bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg); 86 return (bus_space_read_1(sc->sc_bt, sc->sc_bh, RTC_DATA)); 87 } 88 89 void 90 mc146818_write(void *cookie, u_int reg, u_int datum) 91 { 92 struct rtc_ebus_softc *sc = cookie; 93 94 bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_ADDR, reg); 95 bus_space_write_1(sc->sc_bt, sc->sc_bh, RTC_DATA, datum); 96 } 97 98 99 static int 100 rtcmatch_ebus(device_t parent, cfdata_t cf, void *aux) 101 { 102 struct ebus_attach_args *ea = aux; 103 104 return (strcmp(cf->cf_name, ea->ea_name) == 0); 105 } 106 107 static void 108 rtcattach_ebus(device_t parent, device_t self, void *aux) 109 { 110 struct rtc_ebus_softc *sc = device_private(self); 111 struct ebus_attach_args *ea = aux; 112 todr_chip_handle_t handle; 113 114 sc->sc_bt = ea->ea_bustag; 115 if (bus_space_map(sc->sc_bt, EBUS_ADDR_FROM_REG(&ea->ea_reg[0]), 116 ea->ea_reg[0].size, 0, &sc->sc_bh) != 0) 117 { 118 printf(": unable to map registers\n"); 119 return; 120 } 121 122 /* XXX: no "model" property in Krups */ 123 printf(": time-of-day clock\n"); 124 125 /* 126 * Turn interrupts off (clear MC_REGB_?IE bits), just in case 127 * (although they shouldn't be wired to an interrupt 128 * controller on sparcs). 129 */ 130 mc146818_write(sc, MC_REGB, MC_REGB_BINARY | MC_REGB_24HR); 131 132 /* setup our todr_handle */ 133 handle = &sc->sc_todr; 134 handle->cookie = sc; 135 handle->todr_gettime_ymdhms = rtc_gettime_ymdhms; 136 handle->todr_settime_ymdhms = rtc_settime_ymdhms; 137 138 todr_attach(handle); 139 } 140 141 142 static int 143 rtc_gettime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt) 144 { 145 struct rtc_ebus_softc *sc = handle->cookie; 146 u_int year; 147 148 /* update in progress; spin loop */ 149 while (mc146818_read(sc, MC_REGA) & MC_REGA_UIP) 150 continue; 151 152 /* stop updates (XXX: do we need that???) */ 153 mc146818_write(sc, MC_REGB, 154 (mc146818_read(sc, MC_REGB) | MC_REGB_SET)); 155 156 /* read time */ 157 dt->dt_sec = mc146818_read(sc, MC_SEC); 158 dt->dt_min = mc146818_read(sc, MC_MIN); 159 dt->dt_hour = mc146818_read(sc, MC_HOUR); 160 dt->dt_day = mc146818_read(sc, MC_DOM); 161 dt->dt_mon = mc146818_read(sc, MC_MONTH); 162 year = mc146818_read(sc, MC_YEAR); 163 164 /* reenable updates */ 165 mc146818_write(sc, MC_REGB, 166 (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET)); 167 168 /* year in the century 0..99: adjust to AD */ 169 year += 1900; 170 if (year < POSIX_BASE_YEAR && rtc_auto_century_adjust != 0) 171 year += 100; 172 dt->dt_year = year; 173 174 return (0); 175 } 176 177 static int 178 rtc_settime_ymdhms(todr_chip_handle_t handle, struct clock_ymdhms *dt) 179 { 180 struct rtc_ebus_softc *sc = handle->cookie; 181 u_int year; 182 183 year = dt->dt_year - 1900; 184 if (year >= 100 && rtc_auto_century_adjust != 0) 185 year -= 100; 186 187 /* stop updates */ 188 mc146818_write(sc, MC_REGB, 189 (mc146818_read(sc, MC_REGB) | MC_REGB_SET)); 190 191 mc146818_write(sc, MC_SEC, dt->dt_sec); 192 mc146818_write(sc, MC_MIN, dt->dt_min); 193 mc146818_write(sc, MC_HOUR, dt->dt_hour); 194 mc146818_write(sc, MC_DOW, dt->dt_wday + 1); 195 mc146818_write(sc, MC_DOM, dt->dt_day); 196 mc146818_write(sc, MC_MONTH, dt->dt_mon); 197 mc146818_write(sc, MC_YEAR, year); 198 199 /* reenable updates */ 200 mc146818_write(sc, MC_REGB, 201 (mc146818_read(sc, MC_REGB) & ~MC_REGB_SET)); 202 return (0); 203 } 204
Indexes created Tue Sep 30 20:09:53 GMT 2025