clock.c revision 1.12.2.2 1 /* $NetBSD: clock.c,v 1.12.2.2 2007/12/08 18:18:10 mjf Exp $ */
2
3 /*-
4 * Copyright (c) 1990 The Regents of the University of California.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * William Jolitz and Don Ahn.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)clock.c 7.2 (Berkeley) 5/12/91
35 */
36 /*-
37 * Copyright (c) 1993, 1994 Charles M. Hannum.
38 *
39 * This code is derived from software contributed to Berkeley by
40 * William Jolitz and Don Ahn.
41 *
42 * Redistribution and use in source and binary forms, with or without
43 * modification, are permitted provided that the following conditions
44 * are met:
45 * 1. Redistributions of source code must retain the above copyright
46 * notice, this list of conditions and the following disclaimer.
47 * 2. Redistributions in binary form must reproduce the above copyright
48 * notice, this list of conditions and the following disclaimer in the
49 * documentation and/or other materials provided with the distribution.
50 * 3. All advertising materials mentioning features or use of this software
51 * must display the following acknowledgement:
52 * This product includes software developed by the University of
53 * California, Berkeley and its contributors.
54 * 4. Neither the name of the University nor the names of its contributors
55 * may be used to endorse or promote products derived from this software
56 * without specific prior written permission.
57 *
58 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68 * SUCH DAMAGE.
69 *
70 * @(#)clock.c 7.2 (Berkeley) 5/12/91
71 */
72 /*
73 * Mach Operating System
74 * Copyright (c) 1991,1990,1989 Carnegie Mellon University
75 * All Rights Reserved.
76 *
77 * Permission to use, copy, modify and distribute this software and its
78 * documentation is hereby granted, provided that both the copyright
79 * notice and this permission notice appear in all copies of the
80 * software, derivative works or modified versions, and any portions
81 * thereof, and that both notices appear in supporting documentation.
82 *
83 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
84 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
85 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
86 *
87 * Carnegie Mellon requests users of this software to return to
88 *
89 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU
90 * School of Computer Science
91 * Carnegie Mellon University
92 * Pittsburgh PA 15213-3890
93 *
94 * any improvements or extensions that they make and grant Carnegie Mellon
95 * the rights to redistribute these changes.
96 */
97 /*
98 Copyright 1988, 1989 by Intel Corporation, Santa Clara, California.
99
100 All Rights Reserved
101
102 Permission to use, copy, modify, and distribute this software and
103 its documentation for any purpose and without fee is hereby
104 granted, provided that the above copyright notice appears in all
105 copies and that both the copyright notice and this permission notice
106 appear in supporting documentation, and that the name of Intel
107 not be used in advertising or publicity pertaining to distribution
108 of the software without specific, written prior permission.
109
110 INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
111 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
112 IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
113 CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
114 LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
115 NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
116 WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
117 */
118
119 /*
120 * Primitive clock interrupt routines.
121 */
122
123 #include <sys/cdefs.h>
124 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.12.2.2 2007/12/08 18:18:10 mjf Exp $");
125
126 /* #define CLOCKDEBUG */
127 /* #define CLOCK_PARANOIA */
128
129 #include "opt_multiprocessor.h"
130 #include "opt_ntp.h"
131
132 #include <sys/param.h>
133 #include <sys/systm.h>
134 #include <sys/time.h>
135 #include <sys/timetc.h>
136 #include <sys/kernel.h>
137 #include <sys/device.h>
138 #include <sys/mutex.h>
139
140 #include <machine/cpu.h>
141 #include <machine/intr.h>
142 #include <machine/pio.h>
143 #include <machine/cpufunc.h>
144
145 #include <dev/isa/isareg.h>
146 #include <dev/isa/isavar.h>
147 #include <dev/ic/mc146818reg.h>
148 #include <dev/ic/i8253reg.h>
149 #include <i386/isa/nvram.h>
150 #include <x86/x86/tsc.h>
151 #include <dev/clock_subr.h>
152 #include <machine/specialreg.h>
153
154 #include "config_time.h" /* for CONFIG_TIME */
155
156 #ifndef __x86_64__
157 #include "mca.h"
158 #endif
159 #if NMCA > 0
160 #include <machine/mca_machdep.h> /* for MCA_system */
161 #endif
162
163 #include "pcppi.h"
164 #if (NPCPPI > 0)
165 #include <dev/isa/pcppivar.h>
166
167 int sysbeepmatch(struct device *, struct cfdata *, void *);
168 void sysbeepattach(struct device *, struct device *, void *);
169
170 CFATTACH_DECL(sysbeep, sizeof(struct device),
171 sysbeepmatch, sysbeepattach, NULL, NULL);
172
173 static int ppi_attached;
174 static pcppi_tag_t ppicookie;
175 #endif /* PCPPI */
176
177 #ifdef CLOCKDEBUG
178 int clock_debug = 0;
179 #define DPRINTF(arg) if (clock_debug) printf arg
180 #else
181 #define DPRINTF(arg)
182 #endif
183
184 /* Used by lapic.c */
185 unsigned int gettick(void);
186 void sysbeep(int, int);
187 static void tickle_tc(void);
188
189 static int clockintr(void *, struct intrframe *);
190 static void rtcinit(void);
191 static int rtcget(mc_todregs *);
192 static void rtcput(mc_todregs *);
193
194 static int cmoscheck(void);
195
196 static int clock_expandyear(int);
197
198 static unsigned int gettick_broken_latch(void);
199
200 static volatile uint32_t i8254_lastcount;
201 static volatile uint32_t i8254_offset;
202 static volatile int i8254_ticked;
203
204 /* to protect TC timer variables */
205 static __cpu_simple_lock_t tmr_lock = __SIMPLELOCK_UNLOCKED;
206
207 inline u_int mc146818_read(void *, u_int);
208 inline void mc146818_write(void *, u_int, u_int);
209
210 u_int i8254_get_timecount(struct timecounter *);
211 static void rtc_register(void);
212
213 static struct timecounter i8254_timecounter = {
214 i8254_get_timecount, /* get_timecount */
215 0, /* no poll_pps */
216 ~0u, /* counter_mask */
217 TIMER_FREQ, /* frequency */
218 "i8254", /* name */
219 100, /* quality */
220 NULL, /* prev */
221 NULL, /* next */
222 };
223
224 /* XXX use sc? */
225 inline u_int
226 mc146818_read(void *sc, u_int reg)
227 {
228
229 outb(IO_RTC, reg);
230 return (inb(IO_RTC+1));
231 }
232
233 /* XXX use sc? */
234 inline void
235 mc146818_write(void *sc, u_int reg, u_int datum)
236 {
237
238 outb(IO_RTC, reg);
239 outb(IO_RTC+1, datum);
240 }
241
242 u_long rtclock_tval; /* i8254 reload value for countdown */
243 int rtclock_init = 0;
244
245 int clock_broken_latch = 0;
246
247 #ifdef CLOCK_PARANOIA
248 static int ticks[6];
249 #endif
250 /*
251 * i8254 latch check routine:
252 * National Geode (formerly Cyrix MediaGX) has a serious bug in
253 * its built-in i8254-compatible clock module.
254 * machdep sets the variable 'clock_broken_latch' to indicate it.
255 */
256
257 static unsigned int
258 gettick_broken_latch(void)
259 {
260 int v1, v2, v3;
261 int w1, w2, w3;
262 int s;
263
264 /* Don't want someone screwing with the counter while we're here. */
265 s = splhigh();
266 __cpu_simple_lock(&tmr_lock);
267 v1 = inb(IO_TIMER1+TIMER_CNTR0);
268 v1 |= inb(IO_TIMER1+TIMER_CNTR0) << 8;
269 v2 = inb(IO_TIMER1+TIMER_CNTR0);
270 v2 |= inb(IO_TIMER1+TIMER_CNTR0) << 8;
271 v3 = inb(IO_TIMER1+TIMER_CNTR0);
272 v3 |= inb(IO_TIMER1+TIMER_CNTR0) << 8;
273 __cpu_simple_unlock(&tmr_lock);
274 splx(s);
275
276 #ifdef CLOCK_PARANOIA
277 if (clock_debug) {
278 ticks[0] = ticks[3];
279 ticks[1] = ticks[4];
280 ticks[2] = ticks[5];
281 ticks[3] = v1;
282 ticks[4] = v2;
283 ticks[5] = v3;
284 }
285 #endif
286
287 if (v1 >= v2 && v2 >= v3 && v1 - v3 < 0x200)
288 return (v2);
289
290 #define _swap_val(a, b) do { \
291 int c = a; \
292 a = b; \
293 b = c; \
294 } while (0)
295
296 /*
297 * sort v1 v2 v3
298 */
299 if (v1 < v2)
300 _swap_val(v1, v2);
301 if (v2 < v3)
302 _swap_val(v2, v3);
303 if (v1 < v2)
304 _swap_val(v1, v2);
305
306 /*
307 * compute the middle value
308 */
309
310 if (v1 - v3 < 0x200)
311 return (v2);
312
313 w1 = v2 - v3;
314 w2 = v3 - v1 + rtclock_tval;
315 w3 = v1 - v2;
316 if (w1 >= w2) {
317 if (w1 >= w3)
318 return (v1);
319 } else {
320 if (w2 >= w3)
321 return (v2);
322 }
323 return (v3);
324 }
325
326 /* minimal initialization, enough for delay() */
327 void
328 initrtclock(u_long freq)
329 {
330 u_long tval;
331
332 /*
333 * Compute timer_count, the count-down count the timer will be
334 * set to. Also, correctly round
335 * this by carrying an extra bit through the division.
336 */
337 tval = (freq * 2) / (u_long) hz;
338 tval = (tval / 2) + (tval & 0x1);
339
340 /* initialize 8254 clock */
341 outb(IO_TIMER1+TIMER_MODE, TIMER_SEL0|TIMER_RATEGEN|TIMER_16BIT);
342
343 /* Correct rounding will buy us a better precision in timekeeping */
344 outb(IO_TIMER1+TIMER_CNTR0, tval % 256);
345 outb(IO_TIMER1+TIMER_CNTR0, tval / 256);
346
347 rtclock_tval = tval ? tval : 0xFFFF;
348 rtclock_init = 1;
349 }
350
351 void
352 startrtclock(void)
353 {
354 int s;
355
356 if (!rtclock_init)
357 initrtclock(TIMER_FREQ);
358
359 /* Check diagnostic status */
360 if ((s = mc146818_read(NULL, NVRAM_DIAG)) != 0) { /* XXX softc */
361 char bits[128];
362 printf("RTC BIOS diagnostic error %s\n",
363 bitmask_snprintf(s, NVRAM_DIAG_BITS, bits, sizeof(bits)));
364 }
365
366 tc_init(&i8254_timecounter);
367
368 init_TSC();
369 rtc_register();
370 }
371
372 /*
373 * Must be called at splsched().
374 */
375 static void
376 tickle_tc(void)
377 {
378 #if defined(MULTIPROCESSOR)
379 struct cpu_info *ci = curcpu();
380 /*
381 * If we are not the primary CPU, we're not allowed to do
382 * any more work.
383 */
384 if (CPU_IS_PRIMARY(ci) == 0)
385 return;
386 #endif
387 if (rtclock_tval && timecounter->tc_get_timecount == i8254_get_timecount) {
388 __cpu_simple_lock(&tmr_lock);
389 if (i8254_ticked)
390 i8254_ticked = 0;
391 else {
392 i8254_offset += rtclock_tval;
393 i8254_lastcount = 0;
394 }
395 __cpu_simple_unlock(&tmr_lock);
396 }
397
398 }
399
400 static int
401 clockintr(void *arg, struct intrframe *frame)
402 {
403 tickle_tc();
404
405 hardclock((struct clockframe *)frame);
406
407 #if NMCA > 0
408 if (MCA_system) {
409 /* Reset PS/2 clock interrupt by asserting bit 7 of port 0x61 */
410 outb(0x61, inb(0x61) | 0x80);
411 }
412 #endif
413 return -1;
414 }
415
416 u_int
417 i8254_get_timecount(struct timecounter *tc)
418 {
419 u_int count;
420 uint16_t rdval;
421 int s;
422
423 /* Don't want someone screwing with the counter while we're here. */
424 s = splhigh();
425 __cpu_simple_lock(&tmr_lock);
426 /* Select timer0 and latch counter value. */
427 outb(IO_TIMER1 + TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
428 /* insb to make the read atomic */
429 insb(IO_TIMER1+TIMER_CNTR0, &rdval, 2);
430 count = rtclock_tval - rdval;
431 if (rtclock_tval && (count < i8254_lastcount || !i8254_ticked)) {
432 i8254_ticked = 1;
433 i8254_offset += rtclock_tval;
434 }
435 i8254_lastcount = count;
436 count += i8254_offset;
437 __cpu_simple_unlock(&tmr_lock);
438 splx(s);
439
440 return (count);
441 }
442
443 unsigned int
444 gettick(void)
445 {
446 uint16_t rdval;
447 int s;
448
449 if (clock_broken_latch)
450 return (gettick_broken_latch());
451
452 /* Don't want someone screwing with the counter while we're here. */
453 s = splhigh();
454 __cpu_simple_lock(&tmr_lock);
455 /* Select counter 0 and latch it. */
456 outb(IO_TIMER1+TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
457 /* insb to make the read atomic */
458 insb(IO_TIMER1+TIMER_CNTR0, &rdval, 2);
459 __cpu_simple_unlock(&tmr_lock);
460 splx(s);
461
462 return rdval;
463 }
464
465 /*
466 * Wait approximately `n' microseconds.
467 * Relies on timer 1 counting down from (TIMER_FREQ / hz) at TIMER_FREQ Hz.
468 * Note: timer had better have been programmed before this is first used!
469 * (Note that we use `rate generator' mode, which counts at 1:1; `square
470 * wave' mode counts at 2:1).
471 * Don't rely on this being particularly accurate.
472 */
473 void
474 i8254_delay(unsigned int n)
475 {
476 unsigned int cur_tick, initial_tick;
477 int remaining;
478 static const int delaytab[26] = {
479 0, 2, 3, 4, 5, 6, 7, 9, 10, 11,
480 12, 13, 15, 16, 17, 18, 19, 21, 22, 23,
481 24, 25, 27, 28, 29, 30,
482 };
483
484 /* allow DELAY() to be used before startrtclock() */
485 if (!rtclock_init)
486 initrtclock(TIMER_FREQ);
487
488 /*
489 * Read the counter first, so that the rest of the setup overhead is
490 * counted.
491 */
492 initial_tick = gettick();
493
494 if (n <= 25)
495 remaining = delaytab[n];
496 else if (n <= UINT_MAX / TIMER_FREQ) {
497 /*
498 * For unsigned arithmetic, division can be replaced with
499 * multiplication with the inverse and a shift.
500 */
501 remaining = n * TIMER_FREQ / 1000000;
502 } else {
503 /* This is a very long delay.
504 * Being slow here doesn't matter.
505 */
506 remaining = (unsigned long long) n * TIMER_FREQ / 1000000;
507 }
508
509 while (remaining > 0) {
510 #ifdef CLOCK_PARANOIA
511 int delta;
512 cur_tick = gettick();
513 if (cur_tick > initial_tick)
514 delta = rtclock_tval - (cur_tick - initial_tick);
515 else
516 delta = initial_tick - cur_tick;
517 if (delta < 0 || delta >= rtclock_tval / 2) {
518 DPRINTF(("delay: ignore ticks %.4x-%.4x",
519 initial_tick, cur_tick));
520 if (clock_broken_latch) {
521 DPRINTF((" (%.4x %.4x %.4x %.4x %.4x %.4x)\n",
522 ticks[0], ticks[1], ticks[2],
523 ticks[3], ticks[4], ticks[5]));
524 } else {
525 DPRINTF(("\n"));
526 }
527 } else
528 remaining -= delta;
529 #else
530 cur_tick = gettick();
531 if (cur_tick > initial_tick)
532 remaining -= rtclock_tval - (cur_tick - initial_tick);
533 else
534 remaining -= initial_tick - cur_tick;
535 #endif
536 initial_tick = cur_tick;
537 }
538 }
539
540 #if (NPCPPI > 0)
541 int
542 sysbeepmatch(struct device *parent, struct cfdata *match,
543 void *aux)
544 {
545 return (!ppi_attached);
546 }
547
548 void
549 sysbeepattach(struct device *parent, struct device *self,
550 void *aux)
551 {
552 aprint_naive("\n");
553 aprint_normal("\n");
554
555 ppicookie = ((struct pcppi_attach_args *)aux)->pa_cookie;
556 ppi_attached = 1;
557 }
558 #endif
559
560 void
561 sysbeep(int pitch, int period)
562 {
563 #if (NPCPPI > 0)
564 if (ppi_attached)
565 pcppi_bell(ppicookie, pitch, period, 0);
566 #endif
567 }
568
569 void
570 i8254_initclocks(void)
571 {
572
573 /*
574 * XXX If you're doing strange things with multiple clocks, you might
575 * want to keep track of clock handlers.
576 */
577 (void)isa_intr_establish(NULL, 0, IST_PULSE, IPL_CLOCK,
578 (int (*)(void *))clockintr, 0);
579 }
580
581 static void
582 rtcinit(void)
583 {
584 static int first_rtcopen_ever = 1;
585
586 if (!first_rtcopen_ever)
587 return;
588 first_rtcopen_ever = 0;
589
590 mc146818_write(NULL, MC_REGA, /* XXX softc */
591 MC_BASE_32_KHz | MC_RATE_1024_Hz);
592 mc146818_write(NULL, MC_REGB, MC_REGB_24HR); /* XXX softc */
593 }
594
595 static int
596 rtcget(mc_todregs *regs)
597 {
598
599 rtcinit();
600 if ((mc146818_read(NULL, MC_REGD) & MC_REGD_VRT) == 0) /* XXX softc */
601 return (-1);
602 MC146818_GETTOD(NULL, regs); /* XXX softc */
603 return (0);
604 }
605
606 static void
607 rtcput(mc_todregs *regs)
608 {
609
610 rtcinit();
611 MC146818_PUTTOD(NULL, regs); /* XXX softc */
612 }
613
614 /*
615 * check whether the CMOS layout is "standard"-like (ie, not PS/2-like),
616 * to be called at splclock()
617 */
618 static int
619 cmoscheck(void)
620 {
621 int i;
622 unsigned short cksum = 0;
623
624 for (i = 0x10; i <= 0x2d; i++)
625 cksum += mc146818_read(NULL, i); /* XXX softc */
626
627 return (cksum == (mc146818_read(NULL, 0x2e) << 8)
628 + mc146818_read(NULL, 0x2f));
629 }
630
631 #if NMCA > 0
632 /*
633 * Check whether the CMOS layout is PS/2 like, to be called at splclock().
634 */
635 static int cmoscheckps2(void);
636 static int
637 cmoscheckps2(void)
638 {
639 #if 0
640 /* Disabled until I find out the CRC checksum algorithm IBM uses */
641 int i;
642 unsigned short cksum = 0;
643
644 for (i = 0x10; i <= 0x31; i++)
645 cksum += mc146818_read(NULL, i); /* XXX softc */
646
647 return (cksum == (mc146818_read(NULL, 0x32) << 8)
648 + mc146818_read(NULL, 0x33));
649 #else
650 /* Check 'incorrect checksum' bit of IBM PS/2 Diagnostic Status Byte */
651 return ((mc146818_read(NULL, NVRAM_DIAG) & (1<<6)) == 0);
652 #endif
653 }
654 #endif /* NMCA > 0 */
655
656 /*
657 * patchable to control century byte handling:
658 * 1: always update
659 * -1: never touch
660 * 0: try to figure out itself
661 */
662 int rtc_update_century = 0;
663
664 /*
665 * Expand a two-digit year as read from the clock chip
666 * into full width.
667 * Being here, deal with the CMOS century byte.
668 */
669 static int centb = NVRAM_CENTURY;
670 static int
671 clock_expandyear(int clockyear)
672 {
673 int s, clockcentury, cmoscentury;
674
675 clockcentury = (clockyear < 70) ? 20 : 19;
676 clockyear += 100 * clockcentury;
677
678 if (rtc_update_century < 0)
679 return (clockyear);
680
681 s = splclock();
682 if (cmoscheck())
683 cmoscentury = mc146818_read(NULL, NVRAM_CENTURY);
684 #if NMCA > 0
685 else if (MCA_system && cmoscheckps2())
686 cmoscentury = mc146818_read(NULL, (centb = 0x37));
687 #endif
688 else
689 cmoscentury = 0;
690 splx(s);
691 if (!cmoscentury) {
692 #ifdef DIAGNOSTIC
693 printf("clock: unknown CMOS layout\n");
694 #endif
695 return (clockyear);
696 }
697 cmoscentury = bcdtobin(cmoscentury);
698
699 if (cmoscentury != clockcentury) {
700 /* XXX note: saying "century is 20" might confuse the naive. */
701 printf("WARNING: NVRAM century is %d but RTC year is %d\n",
702 cmoscentury, clockyear);
703
704 /* Kludge to roll over century. */
705 if ((rtc_update_century > 0) ||
706 ((cmoscentury == 19) && (clockcentury == 20) &&
707 (clockyear == 2000))) {
708 printf("WARNING: Setting NVRAM century to %d\n",
709 clockcentury);
710 s = splclock();
711 mc146818_write(NULL, centb, bintobcd(clockcentury));
712 splx(s);
713 }
714 } else if (cmoscentury == 19 && rtc_update_century == 0)
715 rtc_update_century = 1; /* will update later in resettodr() */
716
717 return (clockyear);
718 }
719
720 static int
721 rtc_get_ymdhms(todr_chip_handle_t tch, struct clock_ymdhms *dt)
722 {
723 int s;
724 mc_todregs rtclk;
725
726 s = splclock();
727 if (rtcget(&rtclk)) {
728 splx(s);
729 return -1;
730 }
731 splx(s);
732
733 dt->dt_sec = bcdtobin(rtclk[MC_SEC]);
734 dt->dt_min = bcdtobin(rtclk[MC_MIN]);
735 dt->dt_hour = bcdtobin(rtclk[MC_HOUR]);
736 dt->dt_day = bcdtobin(rtclk[MC_DOM]);
737 dt->dt_mon = bcdtobin(rtclk[MC_MONTH]);
738 dt->dt_year = clock_expandyear(bcdtobin(rtclk[MC_YEAR]));
739
740 return 0;
741 }
742
743 static int
744 rtc_set_ymdhms(todr_chip_handle_t tch, struct clock_ymdhms *dt)
745 {
746 mc_todregs rtclk;
747 int century;
748 int s;
749
750 s = splclock();
751 if (rtcget(&rtclk))
752 memset(&rtclk, 0, sizeof(rtclk));
753 splx(s);
754
755 rtclk[MC_SEC] = bintobcd(dt->dt_sec);
756 rtclk[MC_MIN] = bintobcd(dt->dt_min);
757 rtclk[MC_HOUR] = bintobcd(dt->dt_hour);
758 rtclk[MC_DOW] = dt->dt_wday + 1;
759 rtclk[MC_YEAR] = bintobcd(dt->dt_year % 100);
760 rtclk[MC_MONTH] = bintobcd(dt->dt_mon);
761 rtclk[MC_DOM] = bintobcd(dt->dt_day);
762
763 #ifdef DEBUG_CLOCK
764 printf("setclock: %x/%x/%x %x:%x:%x\n", rtclk[MC_YEAR], rtclk[MC_MONTH],
765 rtclk[MC_DOM], rtclk[MC_HOUR], rtclk[MC_MIN], rtclk[MC_SEC]);
766 #endif
767 s = splclock();
768 rtcput(&rtclk);
769 if (rtc_update_century > 0) {
770 century = bintobcd(dt->dt_year / 100);
771 mc146818_write(NULL, centb, century); /* XXX softc */
772 }
773 splx(s);
774 return 0;
775
776 }
777
778 static void
779 rtc_register(void)
780 {
781 static struct todr_chip_handle tch;
782 tch.todr_gettime_ymdhms = rtc_get_ymdhms;
783 tch.todr_settime_ymdhms = rtc_set_ymdhms;
784 tch.todr_setwen = NULL;
785
786 todr_attach(&tch);
787 }
788
789 void
790 setstatclockrate(int arg)
791 {
792 }
793