1 /* 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1982, 1990, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: Utah $Hdr: clock.c 1.18 91/01/21$ 39 * from: @(#)clock.c 8.2 (Berkeley) 1/12/94 40 * from: NetBSD: clock_subr.c,v 1.6 2001/07/07 17:04:02 thorpej Exp 41 * and 42 * from: src/sys/i386/isa/clock.c,v 1.176 2001/09/04 43 * 44 * $FreeBSD$ 45 */ 46 47 /* 48 * Helpers for time-of-day clocks. This is useful for architectures that need 49 * support multiple models of such clocks, and generally serves to make the 50 * code more machine-independent. 51 * If the clock in question can also be used as a time counter, the driver 52 * needs to initiate this. 53 * This code is not yet used by all architectures. 54 */ 55 56 /* 57 * Generic routines to convert between a POSIX date 58 * (seconds since 1/1/1970) and yr/mo/day/hr/min/sec 59 * Derived from NetBSD arch/hp300/hp300/clock.c 60 */ 61 #include <sys/param.h> 62 #include <sys/systm.h> 63 #include <sys/kernel.h> 64 #include <sys/bus.h> 65 #include <sys/clock.h> 66 #include <sys/sysctl.h> 67 #include <sys/timetc.h> 68 69 #include "clock_if.h" 70 71 static __inline int leapyear(int year); 72 static int sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS); 73 74 #define FEBRUARY 2 75 #define days_in_year(y) (leapyear(y) ? 366 : 365) 76 #define days_in_month(y, m) \ 77 (month_days[(m) - 1] + (m == FEBRUARY ? leapyear(y) : 0)) 78 /* Day of week. Days are counted from 1/1/1970, which was a Thursday */ 79 #define day_of_week(days) (((days) + 4) % 7) 80 81 static const int month_days[12] = { 82 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 83 }; 84 85 static device_t clock_dev = NULL; 86 static long clock_res; 87 88 int adjkerntz; /* local offset from GMT in seconds */ 89 int disable_rtc_set; /* disable resettodr() if != 0 */ 90 int wall_cmos_clock; /* wall CMOS clock assumed if != 0 */ 91 92 /* 93 * These have traditionally been in machdep, but should probably be moved to 94 * kern. 95 */ 96 SYSCTL_PROC(_machdep, OID_AUTO, adjkerntz, CTLTYPE_INT|CTLFLAG_RW, 97 &adjkerntz, 0, sysctl_machdep_adjkerntz, "I", ""); 98 99 SYSCTL_INT(_machdep, OID_AUTO, disable_rtc_set, 100 CTLFLAG_RW, &disable_rtc_set, 0, ""); 101 102 SYSCTL_INT(_machdep, OID_AUTO, wall_cmos_clock, 103 CTLFLAG_RW, &wall_cmos_clock, 0, ""); 104 105 static int 106 sysctl_machdep_adjkerntz(SYSCTL_HANDLER_ARGS) 107 { 108 int error; 109 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, 110 req); 111 if (!error && req->newptr) 112 resettodr(); 113 return (error); 114 } 115 116 /* 117 * This inline avoids some unnecessary modulo operations 118 * as compared with the usual macro: 119 * ( ((year % 4) == 0 && 120 * (year % 100) != 0) || 121 * ((year % 400) == 0) ) 122 * It is otherwise equivalent. 123 */ 124 static __inline int 125 leapyear(int year) 126 { 127 int rv = 0; 128 129 if ((year & 3) == 0) { 130 rv = 1; 131 if ((year % 100) == 0) { 132 rv = 0; 133 if ((year % 400) == 0) 134 rv = 1; 135 } 136 } 137 return (rv); 138 } 139 140 int 141 clock_ct_to_ts(struct clocktime *ct, struct timespec *ts) 142 { 143 time_t secs; 144 int i, year, days; 145 146 year = ct->year; 147 148 /* Sanity checks. */ 149 if (ct->mon < 1 || ct->mon > 12 || ct->day < 1 || 150 ct->day > days_in_month(year, ct->mon) || 151 ct->hour > 23 || ct->min > 59 || ct->sec > 59 || 152 ct->year > 2037) /* time_t overflow */ 153 return (EINVAL); 154 155 /* 156 * Compute days since start of time 157 * First from years, then from months. 158 */ 159 days = 0; 160 for (i = POSIX_BASE_YEAR; i < year; i++) 161 days += days_in_year(i); 162 163 /* Months */ 164 for (i = 1; i < ct->mon; i++) 165 days += days_in_month(year, i); 166 days += (ct->day - 1); 167 168 /* Another sanity check. */ 169 if (ct->dow != -1 && ct->dow != day_of_week(days)) 170 return (EINVAL); 171 172 /* Add hours, minutes, seconds. */ 173 secs = ((days * 24 + ct->hour) * 60 + ct->min) * 60 + ct->sec; 174 175 ts->tv_sec = secs; 176 ts->tv_nsec = ct->nsec; 177 return (0); 178 } 179 180 void 181 clock_ts_to_ct(struct timespec *ts, struct clocktime *ct) 182 { 183 int i, year, days; 184 time_t rsec; /* remainder seconds */ 185 time_t secs; 186 187 secs = ts->tv_sec; 188 days = secs / SECDAY; 189 rsec = secs % SECDAY; 190 191 ct->dow = day_of_week(days); 192 193 /* Subtract out whole years, counting them in i. */ 194 for (year = POSIX_BASE_YEAR; days >= days_in_year(year); year++) 195 days -= days_in_year(year); 196 ct->year = year; 197 198 /* Subtract out whole months, counting them in i. */ 199 for (i = 1; days >= days_in_month(year, i); i++) 200 days -= days_in_month(year, i); 201 ct->mon = i; 202 203 /* Days are what is left over (+1) from all that. */ 204 ct->day = days + 1; 205 206 /* Hours, minutes, seconds are easy */ 207 ct->hour = rsec / 3600; 208 rsec = rsec % 3600; 209 ct->min = rsec / 60; 210 rsec = rsec % 60; 211 ct->sec = rsec; 212 ct->nsec = ts->tv_nsec; 213 } 214 215 void 216 clock_register(device_t dev, long res) 217 { 218 219 if (clock_dev != NULL) { 220 if (clock_res > res) { 221 if (bootverbose) { 222 device_printf(dev, "not installed as " 223 "time-of-day clock: clock %s has higher " 224 "resolution\n", device_get_name(clock_dev)); 225 } 226 return; 227 } else { 228 if (bootverbose) { 229 device_printf(clock_dev, "removed as " 230 "time-of-day clock: clock %s has higher " 231 "resolution\n", device_get_name(dev)); 232 } 233 } 234 } 235 clock_dev = dev; 236 clock_res = res; 237 if (bootverbose) { 238 device_printf(dev, "registered as a time-of-day clock " 239 "(resolution %ldus)\n", res); 240 } 241 } 242 243 /* 244 * inittodr and settodr derived from the i386 versions written 245 * by Christoph Robitschko <chmr@edvz.tu-graz.ac.at>, reintroduced and 246 * updated by Chris Stenton <chris@gnome.co.uk> 8/10/94 247 */ 248 249 /* 250 * Initialize the time of day register, based on the time base which is, e.g. 251 * from a filesystem. 252 */ 253 void 254 inittodr(time_t base) 255 { 256 struct timespec diff, ref, ts; 257 int error; 258 259 if (base) { 260 ref.tv_sec = base; 261 ref.tv_nsec = 0; 262 tc_setclock(&ref); 263 } 264 265 if (clock_dev == NULL) { 266 printf("warning: no time-of-day clock registered, system time " 267 "will not be set accurately\n"); 268 return; 269 } 270 error = CLOCK_GETTIME(clock_dev, &ts); 271 if (error != 0 && error != EINVAL) { 272 printf("warning: clock_gettime failed (%d), the system time " 273 "will not be set accurately\n", error); 274 return; 275 } 276 if (error == EINVAL || ts.tv_sec < 0) { 277 printf("Invalid time in real time clock.\n"); 278 printf("Check and reset the date immediately!\n"); 279 } 280 281 ts.tv_sec += tz.tz_minuteswest * 60 + 282 (wall_cmos_clock ? adjkerntz : 0); 283 284 if (timespeccmp(&ref, &ts, >)) { 285 diff = ref; 286 timespecsub(&ref, &ts); 287 } else { 288 diff = ts; 289 timespecsub(&diff, &ref); 290 } 291 if (ts.tv_sec >= 2) { 292 /* badly off, adjust it */ 293 tc_setclock(&ts); 294 } 295 } 296 297 /* 298 * Write system time back to RTC 299 */ 300 void 301 resettodr() 302 { 303 struct timespec ts; 304 int error; 305 306 if (disable_rtc_set || clock_dev == NULL) 307 return; 308 309 getnanotime(&ts); 310 ts.tv_sec -= tz.tz_minuteswest * 60 + (wall_cmos_clock ? adjkerntz : 0); 311 if ((error = CLOCK_SETTIME(clock_dev, &ts)) != 0) { 312 printf("warning: clock_settime failed (%d), time-of-day clock " 313 "not adjusted to system time\n", error); 314 return; 315 } 316 } 317