1 /* $NetBSD: kern_todr.c,v 1.34 2011/02/08 20:20:27 rmind Exp $ */ 2 3 /* 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1992, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department and Ralph Campbell. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * from: Utah Hdr: clock.c 1.18 91/01/21 37 * 38 * @(#)clock.c 8.1 (Berkeley) 6/10/93 39 */ 40 41 #include <sys/cdefs.h> 42 __KERNEL_RCSID(0, "$NetBSD: kern_todr.c,v 1.34 2011/02/08 20:20:27 rmind Exp $"); 43 44 #include <sys/param.h> 45 #include <sys/kernel.h> 46 #include <sys/systm.h> 47 #include <sys/device.h> 48 #include <sys/timetc.h> 49 #include <sys/intr.h> 50 51 #include <dev/clock_subr.h> /* hmm.. this should probably move to sys */ 52 53 static todr_chip_handle_t todr_handle = NULL; 54 55 /* 56 * Attach the clock device to todr_handle. 57 */ 58 void 59 todr_attach(todr_chip_handle_t todr) 60 { 61 62 if (todr_handle) { 63 printf("todr_attach: TOD already configured\n"); 64 return; 65 } 66 todr_handle = todr; 67 } 68 69 static bool timeset = false; 70 71 /* 72 * Set up the system's time, given a `reasonable' time value. 73 */ 74 void 75 inittodr(time_t base) 76 { 77 bool badbase = false; 78 bool waszero = (base == 0); 79 bool goodtime = false; 80 bool badrtc = false; 81 int s; 82 struct timespec ts; 83 struct timeval tv; 84 85 if (base < 5 * SECYR) { 86 struct clock_ymdhms basedate; 87 88 /* 89 * If base is 0, assume filesystem time is just unknown 90 * instead of preposterous. Don't bark. 91 */ 92 if (base != 0) 93 printf("WARNING: preposterous time in file system\n"); 94 /* not going to use it anyway, if the chip is readable */ 95 basedate.dt_year = 2010; 96 basedate.dt_mon = 1; 97 basedate.dt_day = 1; 98 basedate.dt_hour = 12; 99 basedate.dt_min = 0; 100 basedate.dt_sec = 0; 101 base = clock_ymdhms_to_secs(&basedate); 102 badbase = true; 103 } 104 105 /* 106 * Some ports need to be supplied base in order to fabricate a time_t. 107 */ 108 if (todr_handle) 109 todr_handle->base_time = base; 110 111 if ((todr_handle == NULL) || 112 (todr_gettime(todr_handle, &tv) != 0) || 113 (tv.tv_sec < (25 * SECYR))) { 114 115 if (todr_handle != NULL) 116 printf("WARNING: preposterous TOD clock time\n"); 117 else 118 printf("WARNING: no TOD clock present\n"); 119 badrtc = true; 120 } else { 121 time_t deltat = tv.tv_sec - base; 122 123 if (deltat < 0) 124 deltat = -deltat; 125 126 if (!badbase && deltat >= 2 * SECDAY) { 127 128 if (tv.tv_sec < base) { 129 /* 130 * The clock should never go backwards 131 * relative to filesystem time. If it 132 * does by more than the threshold, 133 * believe the filesystem. 134 */ 135 printf("WARNING: clock lost %" PRId64 " days\n", 136 deltat / SECDAY); 137 badrtc = true; 138 } else { 139 aprint_verbose("WARNING: clock gained %" PRId64 140 " days\n", deltat / SECDAY); 141 goodtime = true; 142 } 143 } else { 144 goodtime = true; 145 } 146 } 147 148 /* if the rtc time is bad, use the filesystem time */ 149 if (badrtc) { 150 if (badbase) { 151 printf("WARNING: using default initial time\n"); 152 } else { 153 printf("WARNING: using filesystem time\n"); 154 } 155 tv.tv_sec = base; 156 tv.tv_usec = 0; 157 } 158 159 timeset = true; 160 161 ts.tv_sec = tv.tv_sec; 162 ts.tv_nsec = tv.tv_usec * 1000; 163 s = splclock(); 164 tc_setclock(&ts); 165 splx(s); 166 167 if (waszero || goodtime) 168 return; 169 170 printf("WARNING: CHECK AND RESET THE DATE!\n"); 171 } 172 173 /* 174 * Reset the TODR based on the time value; used when the TODR 175 * has a preposterous value and also when the time is reset 176 * by the stime system call. Also called when the TODR goes past 177 * TODRZERO + 100*(SECYEAR+2*SECDAY) (e.g. on Jan 2 just after midnight) 178 * to wrap the TODR around. 179 */ 180 void 181 resettodr(void) 182 { 183 struct timeval tv; 184 185 /* 186 * We might have been called by boot() due to a crash early 187 * on. Don't reset the clock chip if we don't know what time 188 * it is. 189 */ 190 if (!timeset) 191 return; 192 193 getmicrotime(&tv); 194 195 if (tv.tv_sec == 0) 196 return; 197 198 if (todr_handle) 199 if (todr_settime(todr_handle, &tv) != 0) 200 printf("Cannot set TOD clock time\n"); 201 } 202 203 #ifdef TODR_DEBUG 204 static void 205 todr_debug(const char *prefix, int rv, struct clock_ymdhms *dt, 206 struct timeval *tvp) 207 { 208 struct timeval tv_val; 209 struct clock_ymdhms dt_val; 210 211 if (dt == NULL) { 212 clock_secs_to_ymdhms(tvp->tv_sec, &dt_val); 213 dt = &dt_val; 214 } 215 if (tvp == NULL) { 216 tvp = &tv_val; 217 tvp->tv_sec = clock_ymdhms_to_secs(dt); 218 tvp->tv_usec = 0; 219 } 220 printf("%s: rv = %d\n", prefix, rv); 221 printf("%s: rtc_offset = %d\n", prefix, rtc_offset); 222 printf("%s: %4u/%02u/%02u %02u:%02u:%02u, (wday %d) (epoch %u.%06u)\n", 223 prefix, 224 dt->dt_year, dt->dt_mon, dt->dt_day, 225 dt->dt_hour, dt->dt_min, dt->dt_sec, 226 dt->dt_wday, (unsigned)tvp->tv_sec, (unsigned)tvp->tv_usec); 227 } 228 #else /* !TODR_DEBUG */ 229 #define todr_debug(prefix, rv, dt, tvp) 230 #endif /* TODR_DEBUG */ 231 232 233 int 234 todr_gettime(todr_chip_handle_t tch, struct timeval *tvp) 235 { 236 struct clock_ymdhms dt; 237 int rv; 238 239 if (tch->todr_gettime) { 240 rv = tch->todr_gettime(tch, tvp); 241 /* 242 * Some unconverted ports have their own references to 243 * rtc_offset. A converted port must not do that. 244 */ 245 if (rv == 0) 246 tvp->tv_sec += rtc_offset * 60; 247 todr_debug("TODR-GET-SECS", rv, NULL, tvp); 248 return rv; 249 } else if (tch->todr_gettime_ymdhms) { 250 rv = tch->todr_gettime_ymdhms(tch, &dt); 251 todr_debug("TODR-GET-YMDHMS", rv, &dt, NULL); 252 if (rv) 253 return rv; 254 255 /* 256 * Simple sanity checks. Note that this includes a 257 * value for clocks that can return a leap second. 258 * Note that we don't support double leap seconds, 259 * since this was apparently an error/misunderstanding 260 * on the part of the ISO C committee, and can never 261 * actually occur. If your clock issues us a double 262 * leap second, it must be broken. Ultimately, you'd 263 * have to be trying to read time at precisely that 264 * instant to even notice, so even broken clocks will 265 * work the vast majority of the time. In such a case 266 * it is recommended correction be applied in the 267 * clock driver. 268 */ 269 if (dt.dt_mon < 1 || dt.dt_mon > 12 || 270 dt.dt_day < 1 || dt.dt_day > 31 || 271 dt.dt_hour > 23 || dt.dt_min > 59 || dt.dt_sec > 60) { 272 return EINVAL; 273 } 274 tvp->tv_sec = clock_ymdhms_to_secs(&dt) + rtc_offset * 60; 275 tvp->tv_usec = 0; 276 return tvp->tv_sec < 0 ? EINVAL : 0; 277 } 278 279 return ENXIO; 280 } 281 282 int 283 todr_settime(todr_chip_handle_t tch, struct timeval *tvp) 284 { 285 struct clock_ymdhms dt; 286 int rv; 287 288 if (tch->todr_settime) { 289 /* See comments above in gettime why this is ifdef'd */ 290 struct timeval copy = *tvp; 291 copy.tv_sec -= rtc_offset * 60; 292 rv = tch->todr_settime(tch, ©); 293 todr_debug("TODR-SET-SECS", rv, NULL, tvp); 294 return rv; 295 } else if (tch->todr_settime_ymdhms) { 296 time_t sec = tvp->tv_sec - rtc_offset * 60; 297 if (tvp->tv_usec >= 500000) 298 sec++; 299 clock_secs_to_ymdhms(sec, &dt); 300 rv = tch->todr_settime_ymdhms(tch, &dt); 301 todr_debug("TODR-SET-YMDHMS", rv, &dt, NULL); 302 return rv; 303 } else { 304 return ENXIO; 305 } 306 } 307