kern_todr.c revision 1.24.26.2
1 /* kern_todr.c,v 1.24.26.1 2008/01/09 01:56:12 matt 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, "kern_todr.c,v 1.24.26.1 2008/01/09 01:56:12 matt Exp"); 80 81 #include <sys/param.h> 82 #include <sys/kernel.h> 83 #include <sys/systm.h> 84 #include <sys/device.h> 85 #include <sys/timetc.h> 86 #include <sys/intr.h> 87 88 #include <dev/clock_subr.h> /* hmm.. this should probably move to sys */ 89 90 static todr_chip_handle_t todr_handle = NULL; 91 92 /* 93 * Attach the clock device to todr_handle. 94 */ 95 void 96 todr_attach(todr_chip_handle_t todr) 97 { 98 99 if (todr_handle) { 100 printf("todr_attach: TOD already configured\n"); 101 return; 102 } 103 todr_handle = todr; 104 } 105 106 static int timeset = 0; 107 108 /* 109 * Set up the system's time, given a `reasonable' time value. 110 */ 111 void 112 inittodr(time_t base) 113 { 114 int badbase = 0, waszero = (base == 0), goodtime = 0, badrtc = 0; 115 int s; 116 struct timespec ts; 117 struct timeval tv; 118 119 if (base < 5 * SECYR) { 120 struct clock_ymdhms basedate; 121 122 /* 123 * If base is 0, assume filesystem time is just unknown 124 * instead of preposterous. Don't bark. 125 */ 126 if (base != 0) 127 printf("WARNING: preposterous time in file system\n"); 128 /* not going to use it anyway, if the chip is readable */ 129 basedate.dt_year = 2006; 130 basedate.dt_mon = 1; 131 basedate.dt_day = 1; 132 basedate.dt_hour = 12; 133 basedate.dt_min = 0; 134 basedate.dt_sec = 0; 135 base = clock_ymdhms_to_secs(&basedate); 136 badbase = 1; 137 } 138 139 /* 140 * Some ports need to be supplied base in order to fabricate a time_t. 141 */ 142 if (todr_handle) 143 todr_handle->base_time = base; 144 145 if ((todr_handle == NULL) || 146 (todr_gettime(todr_handle, &tv) != 0) || 147 (tv.tv_sec < (25 * SECYR))) { 148 149 if (todr_handle != NULL) 150 printf("WARNING: preposterous TOD clock time\n"); 151 else 152 printf("WARNING: no TOD clock present\n"); 153 badrtc = 1; 154 } else { 155 int deltat = tv.tv_sec - base; 156 157 if (deltat < 0) 158 deltat = -deltat; 159 160 if ((badbase == 0) && deltat >= 2 * SECDAY) { 161 162 if (tv.tv_sec < base) { 163 /* 164 * The clock should never go backwards 165 * relative to filesystem time. If it 166 * does by more than the threshold, 167 * believe the filesystem. 168 */ 169 printf("WARNING: clock lost %d days\n", 170 deltat / SECDAY); 171 badrtc = 1; 172 } else { 173 printf("WARNING: clock gained %d days\n", 174 deltat / SECDAY); 175 } 176 } else { 177 goodtime = 1; 178 } 179 } 180 181 /* if the rtc time is bad, use the filesystem time */ 182 if (badrtc) { 183 if (badbase) { 184 printf("WARNING: using default initial time\n"); 185 } else { 186 printf("WARNING: using filesystem time\n"); 187 } 188 tv.tv_sec = base; 189 tv.tv_usec = 0; 190 } 191 192 timeset = 1; 193 194 ts.tv_sec = tv.tv_sec; 195 ts.tv_nsec = tv.tv_usec * 1000; 196 s = splclock(); 197 tc_setclock(&ts); 198 splx(s); 199 200 if (waszero || goodtime) 201 return; 202 203 printf("WARNING: CHECK AND RESET THE DATE!\n"); 204 } 205 206 /* 207 * Reset the TODR based on the time value; used when the TODR 208 * has a preposterous value and also when the time is reset 209 * by the stime system call. Also called when the TODR goes past 210 * TODRZERO + 100*(SECYEAR+2*SECDAY) (e.g. on Jan 2 just after midnight) 211 * to wrap the TODR around. 212 */ 213 void 214 resettodr(void) 215 { 216 struct timeval tv; 217 218 /* 219 * We might have been called by boot() due to a crash early 220 * on. Don't reset the clock chip if we don't know what time 221 * it is. 222 */ 223 if (!timeset) 224 return; 225 226 getmicrotime(&tv); 227 228 if (tv.tv_sec == 0) 229 return; 230 231 if (todr_handle) 232 if (todr_settime(todr_handle, &tv) != 0) 233 printf("Cannot set TOD clock time\n"); 234 } 235 236 #ifdef TODR_DEBUG 237 static void 238 todr_debug(const char *prefix, int rv, struct clock_ymdhms *dt, 239 volatile struct timeval *tvp) 240 { 241 struct timeval tv_val; 242 struct clock_ymdhms dt_val; 243 244 if (dt == NULL) { 245 clock_secs_to_ymdhms(tvp->tv_sec, &dt_val); 246 dt = &dt_val; 247 } 248 if (tvp == NULL) { 249 tvp = &tv_val; 250 tvp->tv_sec = clock_ymdhms_to_secs(dt); 251 tvp->tv_usec = 0; 252 } 253 printf("%s: rv = %d\n", prefix, rv); 254 printf("%s: rtc_offset = %d\n", prefix, rtc_offset); 255 printf("%s: %4u/%02u/%02u %02u:%02u:%02u, (wday %d) (epoch %u.%06u)\n", 256 prefix, 257 dt->dt_year, dt->dt_mon, dt->dt_day, 258 dt->dt_hour, dt->dt_min, dt->dt_sec, 259 dt->dt_wday, (unsigned)tvp->tv_sec, (unsigned)tvp->tv_usec); 260 } 261 #else /* !TODR_DEBUG */ 262 #define todr_debug(prefix, rv, dt, tvp) 263 #endif /* TODR_DEBUG */ 264 265 266 int 267 todr_gettime(todr_chip_handle_t tch, volatile struct timeval *tvp) 268 { 269 struct clock_ymdhms dt; 270 int rv; 271 272 if (tch->todr_gettime) { 273 rv = tch->todr_gettime(tch, tvp); 274 /* 275 * Some unconverted ports have their own references to 276 * rtc_offset. A converted port must not do that. 277 */ 278 if (rv == 0) 279 tvp->tv_sec += rtc_offset * 60; 280 todr_debug("TODR-GET-SECS", rv, NULL, tvp); 281 return rv; 282 } else if (tch->todr_gettime_ymdhms) { 283 rv = tch->todr_gettime_ymdhms(tch, &dt); 284 todr_debug("TODR-GET-YMDHMS", rv, &dt, NULL); 285 if (rv) 286 return rv; 287 288 /* 289 * Formerly we had code here that explicitly checked 290 * for 2038 year rollover. 291 * 292 * However, clock_ymdhms_to_secs performs the same 293 * check for us, so we need not worry about it. Note 294 * that this assumes that the tvp->tv_sec member is 295 * a time_t. 296 */ 297 298 /* 299 * Simple sanity checks. Note that this includes a 300 * value for clocks that can return a leap second. 301 * Note that we don't support double leap seconds, 302 * since this was apparently an error/misunderstanding 303 * on the part of the ISO C committee, and can never 304 * actually occur. If your clock issues us a double 305 * leap second, it must be broken. Ultimately, you'd 306 * have to be trying to read time at precisely that 307 * instant to even notice, so even broken clocks will 308 * work the vast majority of the time. In such a case 309 * it is recommended correction be applied in the 310 * clock driver. 311 */ 312 if (dt.dt_mon < 1 || dt.dt_mon > 12 || 313 dt.dt_day < 1 || dt.dt_day > 31 || 314 dt.dt_hour > 23 || dt.dt_min > 59 || dt.dt_sec > 60) { 315 return EINVAL; 316 } 317 tvp->tv_sec = clock_ymdhms_to_secs(&dt) + rtc_offset * 60; 318 tvp->tv_usec = 0; 319 return tvp->tv_sec < 0 ? EINVAL : 0; 320 } 321 322 return ENXIO; 323 } 324 325 int 326 todr_settime(todr_chip_handle_t tch, volatile struct timeval *tvp) 327 { 328 struct clock_ymdhms dt; 329 int rv; 330 331 if (tch->todr_settime) { 332 /* See comments above in gettime why this is ifdef'd */ 333 struct timeval copy = *tvp; 334 copy.tv_sec -= rtc_offset * 60; 335 rv = tch->todr_settime(tch, ©); 336 todr_debug("TODR-SET-SECS", rv, NULL, tvp); 337 return rv; 338 } else if (tch->todr_settime_ymdhms) { 339 time_t sec = tvp->tv_sec - rtc_offset * 60; 340 if (tvp->tv_usec >= 500000) 341 sec++; 342 clock_secs_to_ymdhms(sec, &dt); 343 rv = tch->todr_settime_ymdhms(tch, &dt); 344 todr_debug("TODR-SET-YMDHMS", rv, &dt, NULL); 345 return rv; 346 } else { 347 return ENXIO; 348 } 349 } 350
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