clock.c revision 1.9.10.2 1 /* $NetBSD: clock.c,v 1.9.10.2 2008/01/09 01:49:50 matt 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 1.9.10.2 2008/01/09 01:49:50 matt 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 #include <sys/cpu.h>
140 #include <sys/intr.h>
141
142 #include <machine/pio.h>
143 #include <machine/cpufunc.h>
144 #include <machine/lock.h>
145
146 #include <dev/isa/isareg.h>
147 #include <dev/isa/isavar.h>
148 #include <dev/ic/mc146818reg.h>
149 #include <dev/ic/i8253reg.h>
150 #include <i386/isa/nvram.h>
151 #include <x86/x86/tsc.h>
152 #include <x86/lock.h>
153 #include <dev/clock_subr.h>
154 #include <machine/specialreg.h>
155
156 #include "config_time.h" /* for CONFIG_TIME */
157
158 #ifndef __x86_64__
159 #include "mca.h"
160 #endif
161 #if NMCA > 0
162 #include <machine/mca_machdep.h> /* for MCA_system */
163 #endif
164
165 #include "pcppi.h"
166 #if (NPCPPI > 0)
167 #include <dev/isa/pcppivar.h>
168
169 int sysbeepmatch(struct device *, struct cfdata *, void *);
170 void sysbeepattach(struct device *, struct device *, void *);
171 int sysbeepdetach(device_t, int);
172
173 CFATTACH_DECL(sysbeep, sizeof(struct device),
174 sysbeepmatch, sysbeepattach, sysbeepdetach, NULL);
175
176 static int ppi_attached;
177 static pcppi_tag_t ppicookie;
178 #endif /* PCPPI */
179
180 #ifdef CLOCKDEBUG
181 int clock_debug = 0;
182 #define DPRINTF(arg) if (clock_debug) printf arg
183 #else
184 #define DPRINTF(arg)
185 #endif
186
187 /* Used by lapic.c */
188 unsigned int gettick(void);
189 void sysbeep(int, int);
190 static void tickle_tc(void);
191
192 static int clockintr(void *, struct intrframe *);
193 static void rtcinit(void);
194 static int rtcget(mc_todregs *);
195 static void rtcput(mc_todregs *);
196
197 static int cmoscheck(void);
198
199 static int clock_expandyear(int);
200 int sysbeepdetach(device_t, int);
201
202 static unsigned int gettick_broken_latch(void);
203
204 static volatile uint32_t i8254_lastcount;
205 static volatile uint32_t i8254_offset;
206 static volatile int i8254_ticked;
207
208 /* to protect TC timer variables */
209 static __cpu_simple_lock_t tmr_lock = __SIMPLELOCK_UNLOCKED;
210
211 inline u_int mc146818_read(void *, u_int);
212 inline void mc146818_write(void *, u_int, u_int);
213
214 u_int i8254_get_timecount(struct timecounter *);
215 static void rtc_register(void);
216
217 static struct timecounter i8254_timecounter = {
218 i8254_get_timecount, /* get_timecount */
219 0, /* no poll_pps */
220 ~0u, /* counter_mask */
221 TIMER_FREQ, /* frequency */
222 "i8254", /* name */
223 100, /* quality */
224 NULL, /* prev */
225 NULL, /* next */
226 };
227
228 /* XXX use sc? */
229 inline u_int
230 mc146818_read(void *sc, u_int reg)
231 {
232
233 outb(IO_RTC, reg);
234 return (inb(IO_RTC+1));
235 }
236
237 /* XXX use sc? */
238 inline void
239 mc146818_write(void *sc, u_int reg, u_int datum)
240 {
241
242 outb(IO_RTC, reg);
243 outb(IO_RTC+1, datum);
244 }
245
246 u_long rtclock_tval; /* i8254 reload value for countdown */
247 int rtclock_init = 0;
248
249 int clock_broken_latch = 0;
250
251 #ifdef CLOCK_PARANOIA
252 static int ticks[6];
253 #endif
254 /*
255 * i8254 latch check routine:
256 * National Geode (formerly Cyrix MediaGX) has a serious bug in
257 * its built-in i8254-compatible clock module.
258 * machdep sets the variable 'clock_broken_latch' to indicate it.
259 */
260
261 static unsigned int
262 gettick_broken_latch(void)
263 {
264 int v1, v2, v3;
265 int w1, w2, w3;
266 int s;
267
268 /* Don't want someone screwing with the counter while we're here. */
269 s = splhigh();
270 __cpu_simple_lock(&tmr_lock);
271 v1 = inb(IO_TIMER1+TIMER_CNTR0);
272 v1 |= inb(IO_TIMER1+TIMER_CNTR0) << 8;
273 v2 = inb(IO_TIMER1+TIMER_CNTR0);
274 v2 |= inb(IO_TIMER1+TIMER_CNTR0) << 8;
275 v3 = inb(IO_TIMER1+TIMER_CNTR0);
276 v3 |= inb(IO_TIMER1+TIMER_CNTR0) << 8;
277 __cpu_simple_unlock(&tmr_lock);
278 splx(s);
279
280 #ifdef CLOCK_PARANOIA
281 if (clock_debug) {
282 ticks[0] = ticks[3];
283 ticks[1] = ticks[4];
284 ticks[2] = ticks[5];
285 ticks[3] = v1;
286 ticks[4] = v2;
287 ticks[5] = v3;
288 }
289 #endif
290
291 if (v1 >= v2 && v2 >= v3 && v1 - v3 < 0x200)
292 return (v2);
293
294 #define _swap_val(a, b) do { \
295 int c = a; \
296 a = b; \
297 b = c; \
298 } while (0)
299
300 /*
301 * sort v1 v2 v3
302 */
303 if (v1 < v2)
304 _swap_val(v1, v2);
305 if (v2 < v3)
306 _swap_val(v2, v3);
307 if (v1 < v2)
308 _swap_val(v1, v2);
309
310 /*
311 * compute the middle value
312 */
313
314 if (v1 - v3 < 0x200)
315 return (v2);
316
317 w1 = v2 - v3;
318 w2 = v3 - v1 + rtclock_tval;
319 w3 = v1 - v2;
320 if (w1 >= w2) {
321 if (w1 >= w3)
322 return (v1);
323 } else {
324 if (w2 >= w3)
325 return (v2);
326 }
327 return (v3);
328 }
329
330 /* minimal initialization, enough for delay() */
331 void
332 initrtclock(u_long freq)
333 {
334 u_long tval;
335
336 /*
337 * Compute timer_count, the count-down count the timer will be
338 * set to. Also, correctly round
339 * this by carrying an extra bit through the division.
340 */
341 tval = (freq * 2) / (u_long) hz;
342 tval = (tval / 2) + (tval & 0x1);
343
344 /* initialize 8254 clock */
345 outb(IO_TIMER1+TIMER_MODE, TIMER_SEL0|TIMER_RATEGEN|TIMER_16BIT);
346
347 /* Correct rounding will buy us a better precision in timekeeping */
348 outb(IO_TIMER1+TIMER_CNTR0, tval % 256);
349 outb(IO_TIMER1+TIMER_CNTR0, tval / 256);
350
351 rtclock_tval = tval ? tval : 0xFFFF;
352 rtclock_init = 1;
353 }
354
355 void
356 startrtclock(void)
357 {
358 int s;
359
360 if (!rtclock_init)
361 initrtclock(TIMER_FREQ);
362
363 /* Check diagnostic status */
364 if ((s = mc146818_read(NULL, NVRAM_DIAG)) != 0) { /* XXX softc */
365 char bits[128];
366 printf("RTC BIOS diagnostic error %s\n",
367 bitmask_snprintf(s, NVRAM_DIAG_BITS, bits, sizeof(bits)));
368 }
369
370 tc_init(&i8254_timecounter);
371
372 init_TSC();
373 rtc_register();
374 }
375
376 /*
377 * Must be called at splsched().
378 */
379 static void
380 tickle_tc(void)
381 {
382 #if defined(MULTIPROCESSOR)
383 struct cpu_info *ci = curcpu();
384 /*
385 * If we are not the primary CPU, we're not allowed to do
386 * any more work.
387 */
388 if (CPU_IS_PRIMARY(ci) == 0)
389 return;
390 #endif
391 if (rtclock_tval && timecounter->tc_get_timecount == i8254_get_timecount) {
392 __cpu_simple_lock(&tmr_lock);
393 if (i8254_ticked)
394 i8254_ticked = 0;
395 else {
396 i8254_offset += rtclock_tval;
397 i8254_lastcount = 0;
398 }
399 __cpu_simple_unlock(&tmr_lock);
400 }
401
402 }
403
404 static int
405 clockintr(void *arg, struct intrframe *frame)
406 {
407 tickle_tc();
408
409 hardclock((struct clockframe *)frame);
410
411 #if NMCA > 0
412 if (MCA_system) {
413 /* Reset PS/2 clock interrupt by asserting bit 7 of port 0x61 */
414 outb(0x61, inb(0x61) | 0x80);
415 }
416 #endif
417 return -1;
418 }
419
420 u_int
421 i8254_get_timecount(struct timecounter *tc)
422 {
423 u_int count;
424 uint16_t rdval;
425 int s;
426
427 /* Don't want someone screwing with the counter while we're here. */
428 s = splhigh();
429 __cpu_simple_lock(&tmr_lock);
430 /* Select timer0 and latch counter value. */
431 outb(IO_TIMER1 + TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
432 /* insb to make the read atomic */
433 insb(IO_TIMER1+TIMER_CNTR0, &rdval, 2);
434 count = rtclock_tval - rdval;
435 if (rtclock_tval && (count < i8254_lastcount || !i8254_ticked)) {
436 i8254_ticked = 1;
437 i8254_offset += rtclock_tval;
438 }
439 i8254_lastcount = count;
440 count += i8254_offset;
441 __cpu_simple_unlock(&tmr_lock);
442 splx(s);
443
444 return (count);
445 }
446
447 unsigned int
448 gettick(void)
449 {
450 uint16_t rdval;
451 int s;
452
453 if (clock_broken_latch)
454 return (gettick_broken_latch());
455
456 /* Don't want someone screwing with the counter while we're here. */
457 s = splhigh();
458 __cpu_simple_lock(&tmr_lock);
459 /* Select counter 0 and latch it. */
460 outb(IO_TIMER1+TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
461 /* insb to make the read atomic */
462 insb(IO_TIMER1+TIMER_CNTR0, &rdval, 2);
463 __cpu_simple_unlock(&tmr_lock);
464 splx(s);
465
466 return rdval;
467 }
468
469 /*
470 * Wait approximately `n' microseconds.
471 * Relies on timer 1 counting down from (TIMER_FREQ / hz) at TIMER_FREQ Hz.
472 * Note: timer had better have been programmed before this is first used!
473 * (Note that we use `rate generator' mode, which counts at 1:1; `square
474 * wave' mode counts at 2:1).
475 * Don't rely on this being particularly accurate.
476 */
477 void
478 i8254_delay(unsigned int n)
479 {
480 unsigned int cur_tick, initial_tick;
481 int remaining;
482
483 /* allow DELAY() to be used before startrtclock() */
484 if (!rtclock_init)
485 initrtclock(TIMER_FREQ);
486
487 /*
488 * Read the counter first, so that the rest of the setup overhead is
489 * counted.
490 */
491 initial_tick = gettick();
492
493 if (n <= UINT_MAX / TIMER_FREQ) {
494 /*
495 * For unsigned arithmetic, division can be replaced with
496 * multiplication with the inverse and a shift.
497 */
498 remaining = n * TIMER_FREQ / 1000000;
499 } else {
500 /* This is a very long delay.
501 * Being slow here doesn't matter.
502 */
503 remaining = (unsigned long long) n * TIMER_FREQ / 1000000;
504 }
505
506 while (remaining > 0) {
507 #ifdef CLOCK_PARANOIA
508 int delta;
509 cur_tick = gettick();
510 if (cur_tick > initial_tick)
511 delta = rtclock_tval - (cur_tick - initial_tick);
512 else
513 delta = initial_tick - cur_tick;
514 if (delta < 0 || delta >= rtclock_tval / 2) {
515 DPRINTF(("delay: ignore ticks %.4x-%.4x",
516 initial_tick, cur_tick));
517 if (clock_broken_latch) {
518 DPRINTF((" (%.4x %.4x %.4x %.4x %.4x %.4x)\n",
519 ticks[0], ticks[1], ticks[2],
520 ticks[3], ticks[4], ticks[5]));
521 } else {
522 DPRINTF(("\n"));
523 }
524 } else
525 remaining -= delta;
526 #else
527 cur_tick = gettick();
528 if (cur_tick > initial_tick)
529 remaining -= rtclock_tval - (cur_tick - initial_tick);
530 else
531 remaining -= initial_tick - cur_tick;
532 #endif
533 initial_tick = cur_tick;
534 }
535 }
536
537 #if (NPCPPI > 0)
538 int
539 sysbeepmatch(struct device *parent, struct cfdata *match,
540 void *aux)
541 {
542 return (!ppi_attached);
543 }
544
545 void
546 sysbeepattach(struct device *parent, struct device *self,
547 void *aux)
548 {
549 aprint_naive("\n");
550 aprint_normal("\n");
551
552 ppicookie = ((struct pcppi_attach_args *)aux)->pa_cookie;
553 ppi_attached = 1;
554
555 if (!pmf_device_register(self, NULL, NULL))
556 aprint_error_dev(self, "couldn't establish power handler\n");
557 }
558
559 int
560 sysbeepdetach(device_t self, int flags)
561 {
562 pmf_device_deregister(self);
563 ppi_attached = 0;
564 return 0;
565 }
566 #endif
567
568 void
569 sysbeep(int pitch, int period)
570 {
571 #if (NPCPPI > 0)
572 if (ppi_attached)
573 pcppi_bell(ppicookie, pitch, period, 0);
574 #endif
575 }
576
577 void
578 i8254_initclocks(void)
579 {
580
581 /*
582 * XXX If you're doing strange things with multiple clocks, you might
583 * want to keep track of clock handlers.
584 */
585 (void)isa_intr_establish(NULL, 0, IST_PULSE, IPL_CLOCK,
586 (int (*)(void *))clockintr, 0);
587 }
588
589 static void
590 rtcinit(void)
591 {
592 static int first_rtcopen_ever = 1;
593
594 if (!first_rtcopen_ever)
595 return;
596 first_rtcopen_ever = 0;
597
598 mc146818_write(NULL, MC_REGA, /* XXX softc */
599 MC_BASE_32_KHz | MC_RATE_1024_Hz);
600 mc146818_write(NULL, MC_REGB, MC_REGB_24HR); /* XXX softc */
601 }
602
603 static int
604 rtcget(mc_todregs *regs)
605 {
606
607 rtcinit();
608 if ((mc146818_read(NULL, MC_REGD) & MC_REGD_VRT) == 0) /* XXX softc */
609 return (-1);
610 MC146818_GETTOD(NULL, regs); /* XXX softc */
611 return (0);
612 }
613
614 static void
615 rtcput(mc_todregs *regs)
616 {
617
618 rtcinit();
619 MC146818_PUTTOD(NULL, regs); /* XXX softc */
620 }
621
622 /*
623 * check whether the CMOS layout is "standard"-like (ie, not PS/2-like),
624 * to be called at splclock()
625 */
626 static int
627 cmoscheck(void)
628 {
629 int i;
630 unsigned short cksum = 0;
631
632 for (i = 0x10; i <= 0x2d; i++)
633 cksum += mc146818_read(NULL, i); /* XXX softc */
634
635 return (cksum == (mc146818_read(NULL, 0x2e) << 8)
636 + mc146818_read(NULL, 0x2f));
637 }
638
639 #if NMCA > 0
640 /*
641 * Check whether the CMOS layout is PS/2 like, to be called at splclock().
642 */
643 static int cmoscheckps2(void);
644 static int
645 cmoscheckps2(void)
646 {
647 #if 0
648 /* Disabled until I find out the CRC checksum algorithm IBM uses */
649 int i;
650 unsigned short cksum = 0;
651
652 for (i = 0x10; i <= 0x31; i++)
653 cksum += mc146818_read(NULL, i); /* XXX softc */
654
655 return (cksum == (mc146818_read(NULL, 0x32) << 8)
656 + mc146818_read(NULL, 0x33));
657 #else
658 /* Check 'incorrect checksum' bit of IBM PS/2 Diagnostic Status Byte */
659 return ((mc146818_read(NULL, NVRAM_DIAG) & (1<<6)) == 0);
660 #endif
661 }
662 #endif /* NMCA > 0 */
663
664 /*
665 * patchable to control century byte handling:
666 * 1: always update
667 * -1: never touch
668 * 0: try to figure out itself
669 */
670 int rtc_update_century = 0;
671
672 /*
673 * Expand a two-digit year as read from the clock chip
674 * into full width.
675 * Being here, deal with the CMOS century byte.
676 */
677 static int centb = NVRAM_CENTURY;
678 static int
679 clock_expandyear(int clockyear)
680 {
681 int s, clockcentury, cmoscentury;
682
683 clockcentury = (clockyear < 70) ? 20 : 19;
684 clockyear += 100 * clockcentury;
685
686 if (rtc_update_century < 0)
687 return (clockyear);
688
689 s = splclock();
690 if (cmoscheck())
691 cmoscentury = mc146818_read(NULL, NVRAM_CENTURY);
692 #if NMCA > 0
693 else if (MCA_system && cmoscheckps2())
694 cmoscentury = mc146818_read(NULL, (centb = 0x37));
695 #endif
696 else
697 cmoscentury = 0;
698 splx(s);
699 if (!cmoscentury) {
700 #ifdef DIAGNOSTIC
701 printf("clock: unknown CMOS layout\n");
702 #endif
703 return (clockyear);
704 }
705 cmoscentury = bcdtobin(cmoscentury);
706
707 if (cmoscentury != clockcentury) {
708 /* XXX note: saying "century is 20" might confuse the naive. */
709 printf("WARNING: NVRAM century is %d but RTC year is %d\n",
710 cmoscentury, clockyear);
711
712 /* Kludge to roll over century. */
713 if ((rtc_update_century > 0) ||
714 ((cmoscentury == 19) && (clockcentury == 20) &&
715 (clockyear == 2000))) {
716 printf("WARNING: Setting NVRAM century to %d\n",
717 clockcentury);
718 s = splclock();
719 mc146818_write(NULL, centb, bintobcd(clockcentury));
720 splx(s);
721 }
722 } else if (cmoscentury == 19 && rtc_update_century == 0)
723 rtc_update_century = 1; /* will update later in resettodr() */
724
725 return (clockyear);
726 }
727
728 static int
729 rtc_get_ymdhms(todr_chip_handle_t tch, struct clock_ymdhms *dt)
730 {
731 int s;
732 mc_todregs rtclk;
733
734 s = splclock();
735 if (rtcget(&rtclk)) {
736 splx(s);
737 return -1;
738 }
739 splx(s);
740
741 dt->dt_sec = bcdtobin(rtclk[MC_SEC]);
742 dt->dt_min = bcdtobin(rtclk[MC_MIN]);
743 dt->dt_hour = bcdtobin(rtclk[MC_HOUR]);
744 dt->dt_day = bcdtobin(rtclk[MC_DOM]);
745 dt->dt_mon = bcdtobin(rtclk[MC_MONTH]);
746 dt->dt_year = clock_expandyear(bcdtobin(rtclk[MC_YEAR]));
747
748 return 0;
749 }
750
751 static int
752 rtc_set_ymdhms(todr_chip_handle_t tch, struct clock_ymdhms *dt)
753 {
754 mc_todregs rtclk;
755 int century;
756 int s;
757
758 s = splclock();
759 if (rtcget(&rtclk))
760 memset(&rtclk, 0, sizeof(rtclk));
761 splx(s);
762
763 rtclk[MC_SEC] = bintobcd(dt->dt_sec);
764 rtclk[MC_MIN] = bintobcd(dt->dt_min);
765 rtclk[MC_HOUR] = bintobcd(dt->dt_hour);
766 rtclk[MC_DOW] = dt->dt_wday + 1;
767 rtclk[MC_YEAR] = bintobcd(dt->dt_year % 100);
768 rtclk[MC_MONTH] = bintobcd(dt->dt_mon);
769 rtclk[MC_DOM] = bintobcd(dt->dt_day);
770
771 #ifdef DEBUG_CLOCK
772 printf("setclock: %x/%x/%x %x:%x:%x\n", rtclk[MC_YEAR], rtclk[MC_MONTH],
773 rtclk[MC_DOM], rtclk[MC_HOUR], rtclk[MC_MIN], rtclk[MC_SEC]);
774 #endif
775 s = splclock();
776 rtcput(&rtclk);
777 if (rtc_update_century > 0) {
778 century = bintobcd(dt->dt_year / 100);
779 mc146818_write(NULL, centb, century); /* XXX softc */
780 }
781 splx(s);
782 return 0;
783
784 }
785
786 static void
787 rtc_register(void)
788 {
789 static struct todr_chip_handle tch;
790 tch.todr_gettime_ymdhms = rtc_get_ymdhms;
791 tch.todr_settime_ymdhms = rtc_set_ymdhms;
792 tch.todr_setwen = NULL;
793
794 todr_attach(&tch);
795 }
796
797 void
798 setstatclockrate(int arg)
799 {
800 }
801