kern_todr.c revision 1.2 1 /* $NetBSD: kern_todr.c,v 1.2 2006/09/03 05:25:05 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 1.2 2006/09/03 05:25:05 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 /*
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 base = 21*SECYR + 186*SECDAY + SECDAY/2;
130 badbase = 1;
131 }
132
133 if ((todr_handle == NULL) ||
134 (todr_gettime(todr_handle, &tv) != 0) ||
135 (tv.tv_sec < (5 * SECYR))) {
136
137 if (todr_handle != NULL)
138 printf("WARNING: preposterous TOD clock time\n");
139 else
140 printf("WARNING: no TOD clock present\n");
141 badrtc = 1;
142 } else {
143 int deltat = tv.tv_sec - base;
144
145 if (deltat < 0)
146 deltat = -deltat;
147
148 if (deltat >= 2 * SECDAY) {
149
150 if (tv.tv_sec < base) {
151 /*
152 * The clock should never go backwards
153 * relative to filesystem time. If it
154 * does by more than the threshold,
155 * believe the filesystem.
156 */
157 printf("WARNING: clock lost %d days\n",
158 deltat / SECDAY);
159 badrtc = 1;
160 }
161 else {
162 printf("WARNING: clock gained %d days\n",
163 deltat / SECDAY);
164 }
165 } else {
166 goodtime = 1;
167 }
168 }
169
170 /* if the rtc time is bad, use the filesystem time */
171 if (badrtc) {
172 if (badbase) {
173 printf("WARNING: using default initial time\n");
174 } else {
175 printf("WARNING: using filesystem time\n");
176 }
177 tv.tv_sec = base;
178 tv.tv_usec = 0;
179 }
180
181 timeset = 1;
182
183 #ifdef __HAVE_TIMECOUNTER
184 ts.tv_sec = tv.tv_sec;
185 ts.tv_nsec = tv.tv_usec * 1000;
186 tc_setclock(&ts);
187 #else
188 time = tv;
189 #endif
190
191 if (waszero || goodtime)
192 return;
193
194
195 printf("WARNING: CHECK AND RESET THE DATE!\n");
196
197 }
198
199 /*
200 * Reset the TODR based on the time value; used when the TODR
201 * has a preposterous value and also when the time is reset
202 * by the stime system call. Also called when the TODR goes past
203 * TODRZERO + 100*(SECYEAR+2*SECDAY) (e.g. on Jan 2 just after midnight)
204 * to wrap the TODR around.
205 */
206 void
207 resettodr(void)
208 {
209 #ifdef __HAVE_TIMECOUNTER
210 struct timeval time;
211 #endif
212
213 /*
214 * We might have been called by boot() due to a crash early
215 * on. Don't reset the clock chip if we don't know what time
216 * it is.
217 */
218 if (!timeset)
219 return;
220
221 #ifdef __HAVE_TIMECOUNTER
222 getmicrotime(&time);
223 #endif
224
225 if (time.tv_sec == 0)
226 return;
227
228 if (todr_handle)
229 if (todr_settime(todr_handle, &time) != 0)
230 printf("Cannot set TOD clock time\n");
231 }
232
233 #endif /* __HAVE_GENERIC_TODR */
234