kern_todr.c revision 1.6
1 /* $NetBSD: kern_todr.c,v 1.6 2006/09/07 00:10:49 gdamore Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department and Ralph Campbell. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * from: Utah Hdr: clock.c 1.18 91/01/21 36 * 37 * @(#)clock.c 8.1 (Berkeley) 6/10/93 38 */ 39 /* 40 * Copyright (c) 1988 University of Utah. 41 * 42 * This code is derived from software contributed to Berkeley by 43 * the Systems Programming Group of the University of Utah Computer 44 * Science Department and Ralph Campbell. 45 * 46 * Redistribution and use in source and binary forms, with or without 47 * modification, are permitted provided that the following conditions 48 * are met: 49 * 1. Redistributions of source code must retain the above copyright 50 * notice, this list of conditions and the following disclaimer. 51 * 2. Redistributions in binary form must reproduce the above copyright 52 * notice, this list of conditions and the following disclaimer in the 53 * documentation and/or other materials provided with the distribution. 54 * 3. All advertising materials mentioning features or use of this software 55 * must display the following acknowledgement: 56 * This product includes software developed by the University of 57 * California, Berkeley and its contributors. 58 * 4. Neither the name of the University nor the names of its contributors 59 * may be used to endorse or promote products derived from this software 60 * without specific prior written permission. 61 * 62 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 63 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 64 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 65 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 66 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 67 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 68 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 69 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 70 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 71 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 72 * SUCH DAMAGE. 73 * 74 * from: Utah Hdr: clock.c 1.18 91/01/21 75 * 76 * @(#)clock.c 8.1 (Berkeley) 6/10/93 77 */ 78 #include <sys/cdefs.h> 79 __KERNEL_RCSID(0, "$NetBSD: kern_todr.c,v 1.6 2006/09/07 00:10:49 gdamore Exp $"); 80 81 #include <sys/param.h> 82 83 #ifdef __HAVE_GENERIC_TODR 84 85 #include <sys/kernel.h> 86 #include <sys/systm.h> 87 #include <sys/device.h> 88 #include <sys/timetc.h> 89 #include <dev/clock_subr.h> /* hmm.. this should probably move to sys */ 90 91 static todr_chip_handle_t todr_handle = NULL; 92 93 /* 94 * Attach the clock device to todr_handle. 95 */ 96 void 97 todr_attach(todr_chip_handle_t todr) 98 { 99 100 if (todr_handle) { 101 printf("todr_attach: TOD already configured\n"); 102 return; 103 } 104 todr_handle = todr; 105 } 106 107 static int timeset = 0; 108 109 /* 110 * Set up the system's time, given a `reasonable' time value. 111 */ 112 void 113 inittodr(time_t base) 114 { 115 int badbase = 0, waszero = (base == 0), goodtime = 0, badrtc = 0; 116 #ifdef __HAVE_TIMECOUNTER 117 struct timespec ts; 118 #endif 119 struct timeval tv; 120 121 if (base < 5 * SECYR) { 122 struct clock_ymdhms basedate; 123 124 /* 125 * If base is 0, assume filesystem time is just unknown 126 * instead of preposterous. Don't bark. 127 */ 128 if (base != 0) 129 printf("WARNING: preposterous time in file system\n"); 130 /* not going to use it anyway, if the chip is readable */ 131 basedate.dt_year = 2006; 132 basedate.dt_mon = 1; 133 basedate.dt_day = 1; 134 basedate.dt_hour = 12; 135 basedate.dt_min = 0; 136 basedate.dt_sec = 0; 137 base = clock_ymdhms_to_secs(&basedate); 138 badbase = 1; 139 } 140 141 /* 142 * Some ports need to be supplied base in order to fabricate a time_t. 143 */ 144 tv.tv_sec = base; 145 tv.tv_usec = 0; 146 147 if ((todr_handle == NULL) || 148 (todr_gettime(todr_handle, &tv) != 0) || 149 (tv.tv_sec < (5 * SECYR))) { 150 151 if (todr_handle != NULL) 152 printf("WARNING: preposterous TOD clock time\n"); 153 else 154 printf("WARNING: no TOD clock present\n"); 155 badrtc = 1; 156 } else { 157 int deltat = tv.tv_sec - base; 158 159 if (deltat < 0) 160 deltat = -deltat; 161 162 if ((badbase == 0) && deltat >= 2 * SECDAY) { 163 164 if (tv.tv_sec < base) { 165 /* 166 * The clock should never go backwards 167 * relative to filesystem time. If it 168 * does by more than the threshold, 169 * believe the filesystem. 170 */ 171 printf("WARNING: clock lost %d days\n", 172 deltat / SECDAY); 173 badrtc = 1; 174 } 175 else { 176 printf("WARNING: clock gained %d days\n", 177 deltat / SECDAY); 178 } 179 } else { 180 goodtime = 1; 181 } 182 } 183 184 /* if the rtc time is bad, use the filesystem time */ 185 if (badrtc) { 186 if (badbase) { 187 printf("WARNING: using default initial time\n"); 188 } else { 189 printf("WARNING: using filesystem time\n"); 190 } 191 tv.tv_sec = base; 192 tv.tv_usec = 0; 193 } 194 195 timeset = 1; 196 197 #ifdef __HAVE_TIMECOUNTER 198 ts.tv_sec = tv.tv_sec; 199 ts.tv_nsec = tv.tv_usec * 1000; 200 tc_setclock(&ts); 201 #else 202 time = tv; 203 #endif 204 205 if (waszero || goodtime) 206 return; 207 208 printf("WARNING: CHECK AND RESET THE DATE!\n"); 209 } 210 211 /* 212 * Reset the TODR based on the time value; used when the TODR 213 * has a preposterous value and also when the time is reset 214 * by the stime system call. Also called when the TODR goes past 215 * TODRZERO + 100*(SECYEAR+2*SECDAY) (e.g. on Jan 2 just after midnight) 216 * to wrap the TODR around. 217 */ 218 void 219 resettodr(void) 220 { 221 #ifdef __HAVE_TIMECOUNTER 222 struct timeval time; 223 #endif 224 225 /* 226 * We might have been called by boot() due to a crash early 227 * on. Don't reset the clock chip if we don't know what time 228 * it is. 229 */ 230 if (!timeset) 231 return; 232 233 #ifdef __HAVE_TIMECOUNTER 234 getmicrotime(&time); 235 #endif 236 237 if (time.tv_sec == 0) 238 return; 239 240 if (todr_handle) 241 if (todr_settime(todr_handle, &time) != 0) 242 printf("Cannot set TOD clock time\n"); 243 } 244 245 #endif /* __HAVE_GENERIC_TODR */ 246 247 248 int 249 todr_gettime(todr_chip_handle_t tch, struct timeval *tvp) 250 { 251 struct clock_ymdhms dt; 252 int rv; 253 254 if (tch->todr_gettime) 255 return tch->todr_gettime(tch, tvp); 256 257 if (tch->todr_gettime_ymdhms) { 258 if ((rv = tch->todr_gettime_ymdhms(tch, &dt)) != 0) 259 return rv; 260 /* 261 * If tv_sec is 32 bits, then the "End of Time" is Mon 262 * Jan 18 22:14:07 2038 (US/Eastern) This code copes 263 * with RTC's past the end of time if tv_sec is an 264 * int32 or less. Needed because sometimes RTCs screw 265 * up or are badly set, and that would cause the time 266 * to go negative in the calculation below, which 267 * causes Very Bad Mojo. This at least lets the user 268 * boot and fix the problem. Note the code is self 269 * eliminating once tv_sec goes to 64 bits. 270 */ 271 if ((sizeof (tvp->tv_sec) <= sizeof (int32_t)) && 272 (dt.dt_year >= 2038)) { 273 return -1; 274 } 275 276 tvp->tv_sec = clock_ymdhms_to_secs(&dt) + rtc_offset * 60; 277 tvp->tv_usec = 0; 278 return 0; 279 } 280 281 return -1; 282 } 283 284 int 285 todr_settime(todr_chip_handle_t tch, struct timeval *tvp) 286 { 287 struct clock_ymdhms dt; 288 289 if (tch->todr_settime) 290 return tch->todr_settime(tch, tvp); 291 292 if (tch->todr_settime_ymdhms) { 293 clock_secs_to_ymdhms(tvp->tv_sec - rtc_offset * 60, &dt); 294 return tch->todr_settime_ymdhms(tch, &dt); 295 } 296 297 return -1; 298 } 299
Indexes created Sun Sep 21 16:09:51 GMT 2025