FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_todr.c
1 /* $NetBSD: kern_todr.c,v 1.27 2008/01/20 18:09:12 joerg 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 1.27 2008/01/20 18:09:12 joerg 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 }
Cache object: cdd84912f12b87e192c506cf16e5b993
|