1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz and Don Ahn.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * from: @(#)clock.c 7.2 (Berkeley) 5/12/91
33 */
34
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD: head/sys/pc98/cbus/pcrtc.c 170289 2007-06-04 18:25:08Z dwmalone $");
37
38/*
39 * Routines to handle clock hardware.
40 */
41
42/*
43 * inittodr, settodr and support routines written
44 * by Christoph Robitschko <chmr@edvz.tu-graz.ac.at>
45 *
46 * reintroduced and updated by Chris Stenton <chris@gnome.co.uk> 8/10/94
47 */
48
49/*
50 * modified for PC98 by Kakefuda
51 */
52
53#include "opt_apic.h"
54#include "opt_clock.h"
55#include "opt_isa.h"
56#include "opt_mca.h"
57
58#include <sys/param.h>
59#include <sys/systm.h>
60#include <sys/bus.h>
61#include <sys/clock.h>
62#include <sys/lock.h>
63#include <sys/kdb.h>
64#include <sys/mutex.h>
65#include <sys/proc.h>
66#include <sys/time.h>
67#include <sys/timetc.h>
68#include <sys/kernel.h>
69#include <sys/limits.h>
70#include <sys/module.h>
71#include <sys/sysctl.h>
72#include <sys/cons.h>
73#include <sys/power.h>
74
75#include <machine/clock.h>
76#include <machine/cpu.h>
77#include <machine/cputypes.h>
78#include <machine/frame.h>
79#include <machine/intr_machdep.h>
80#include <machine/md_var.h>
81#include <machine/psl.h>
82#ifdef DEV_APIC
83#include <machine/apicvar.h>
84#endif
85#include <machine/specialreg.h>
86#include <machine/ppireg.h>
87#include <machine/timerreg.h>
88
89#include <i386/isa/icu.h>
90#include <pc98/cbus/cbus.h>
91#include <pc98/pc98/pc98_machdep.h>
92#ifdef DEV_ISA
93#include <isa/isavar.h>
94#endif
95
96#define TIMER_DIV(x) ((timer_freq + (x) / 2) / (x))
97
98int clkintr_pending;
99int pscnt = 1;
100int psdiv = 1;
101int statclock_disable;
102#ifndef TIMER_FREQ
103#define TIMER_FREQ 2457600
104#endif
105u_int timer_freq = TIMER_FREQ;
106int timer0_max_count;
107int timer0_real_max_count;
108
109static int beeping = 0;
110static struct mtx clock_lock;
111static struct intsrc *i8254_intsrc;
112static u_int32_t i8254_lastcount;
113static u_int32_t i8254_offset;
114static int (*i8254_pending)(struct intsrc *);
115static int i8254_ticked;
116static int using_lapic_timer;
117
118/* Values for timerX_state: */
119#define RELEASED 0
120#define RELEASE_PENDING 1
121#define ACQUIRED 2
122#define ACQUIRE_PENDING 3
123
124static u_char timer1_state;
125static u_char timer2_state;
126static void rtc_serialcombit(int);
127static void rtc_serialcom(int);
128static int rtc_inb(void);
129static void rtc_outb(int);
130
131static unsigned i8254_get_timecount(struct timecounter *tc);
132static unsigned i8254_simple_get_timecount(struct timecounter *tc);
133static void set_timer_freq(u_int freq, int intr_freq);
134
135static struct timecounter i8254_timecounter = {
136 i8254_get_timecount, /* get_timecount */
137 0, /* no poll_pps */
138 ~0u, /* counter_mask */
139 0, /* frequency */
140 "i8254", /* name */
141 0 /* quality */
142};
143
144static int
145clkintr(struct trapframe *frame)
146{
147
148 if (timecounter->tc_get_timecount == i8254_get_timecount) {
149 mtx_lock_spin(&clock_lock);
150 if (i8254_ticked)
151 i8254_ticked = 0;
152 else {
153 i8254_offset += timer0_max_count;
154 i8254_lastcount = 0;
155 }
156 clkintr_pending = 0;
157 mtx_unlock_spin(&clock_lock);
158 }
159 KASSERT(!using_lapic_timer, ("clk interrupt enabled with lapic timer"));
160 hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
161 return (FILTER_HANDLED);
162}
163
164int
165acquire_timer1(int mode)
166{
167
168 if (timer1_state != RELEASED)
169 return (-1);
170 timer1_state = ACQUIRED;
171
172 /*
173 * This access to the timer registers is as atomic as possible
174 * because it is a single instruction. We could do better if we
175 * knew the rate. Use of splclock() limits glitches to 10-100us,
176 * and this is probably good enough for timer2, so we aren't as
177 * careful with it as with timer0.
178 */
179 outb(TIMER_MODE, TIMER_SEL1 | (mode & 0x3f));
180
181 return (0);
182}
183
184int
185acquire_timer2(int mode)
186{
187
188 if (timer2_state != RELEASED)
189 return (-1);
190 timer2_state = ACQUIRED;
191
192 /*
193 * This access to the timer registers is as atomic as possible
194 * because it is a single instruction. We could do better if we
195 * knew the rate. Use of splclock() limits glitches to 10-100us,
196 * and this is probably good enough for timer2, so we aren't as
197 * careful with it as with timer0.
198 */
199 outb(TIMER_MODE, TIMER_SEL2 | (mode & 0x3f));
200
201 return (0);
202}
203
204int
205release_timer1()
206{
207
208 if (timer1_state != ACQUIRED)
209 return (-1);
210 timer1_state = RELEASED;
211 outb(TIMER_MODE, TIMER_SEL1 | TIMER_SQWAVE | TIMER_16BIT);
212 return (0);
213}
214
215int
216release_timer2()
217{
218
219 if (timer2_state != ACQUIRED)
220 return (-1);
221 timer2_state = RELEASED;
222 outb(TIMER_MODE, TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT);
223 return (0);
224}
225
226
227static int
228getit(void)
229{
230 int high, low;
231
232 mtx_lock_spin(&clock_lock);
233
234 /* Select timer0 and latch counter value. */
235 outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
236
237 low = inb(TIMER_CNTR0);
238 high = inb(TIMER_CNTR0);
239
240 mtx_unlock_spin(&clock_lock);
241 return ((high << 8) | low);
242}
243
244/*
245 * Wait "n" microseconds.
246 * Relies on timer 1 counting down from (timer_freq / hz)
247 * Note: timer had better have been programmed before this is first used!
248 */
249void
250DELAY(int n)
251{
252 int delta, prev_tick, tick, ticks_left;
253
254#ifdef DELAYDEBUG
255 int getit_calls = 1;
256 int n1;
257 static int state = 0;
258
259 if (state == 0) {
260 state = 1;
261 for (n1 = 1; n1 <= 10000000; n1 *= 10)
262 DELAY(n1);
263 state = 2;
264 }
265 if (state == 1)
266 printf("DELAY(%d)...", n);
267#endif
268 /*
269 * Read the counter first, so that the rest of the setup overhead is
270 * counted. Guess the initial overhead is 20 usec (on most systems it
271 * takes about 1.5 usec for each of the i/o's in getit(). The loop
272 * takes about 6 usec on a 486/33 and 13 usec on a 386/20. The
273 * multiplications and divisions to scale the count take a while).
274 *
275 * However, if ddb is active then use a fake counter since reading
276 * the i8254 counter involves acquiring a lock. ddb must not do
277 * locking for many reasons, but it calls here for at least atkbd
278 * input.
279 */
280#ifdef KDB
281 if (kdb_active)
282 prev_tick = 1;
283 else
284#endif
285 prev_tick = getit();
286 n -= 0; /* XXX actually guess no initial overhead */
287 /*
288 * Calculate (n * (timer_freq / 1e6)) without using floating point
289 * and without any avoidable overflows.
290 */
291 if (n <= 0)
292 ticks_left = 0;
293 else if (n < 256)
294 /*
295 * Use fixed point to avoid a slow division by 1000000.
296 * 39099 = 1193182 * 2^15 / 10^6 rounded to nearest.
297 * 2^15 is the first power of 2 that gives exact results
298 * for n between 0 and 256.
299 */
300 ticks_left = ((u_int)n * 39099 + (1 << 15) - 1) >> 15;
301 else
302 /*
303 * Don't bother using fixed point, although gcc-2.7.2
304 * generates particularly poor code for the long long
305 * division, since even the slow way will complete long
306 * before the delay is up (unless we're interrupted).
307 */
308 ticks_left = ((u_int)n * (long long)timer_freq + 999999)
309 / 1000000;
310
311 while (ticks_left > 0) {
312#ifdef KDB
313 if (kdb_active) {
314 outb(0x5f, 0);
315 tick = prev_tick - 1;
316 if (tick <= 0)
317 tick = timer0_max_count;
318 } else
319#endif
320 tick = getit();
321#ifdef DELAYDEBUG
322 ++getit_calls;
323#endif
324 delta = prev_tick - tick;
325 prev_tick = tick;
326 if (delta < 0) {
327 delta += timer0_max_count;
328 /*
329 * Guard against timer0_max_count being wrong.
330 * This shouldn't happen in normal operation,
331 * but it may happen if set_timer_freq() is
332 * traced.
333 */
334 if (delta < 0)
335 delta = 0;
336 }
337 ticks_left -= delta;
338 }
339#ifdef DELAYDEBUG
340 if (state == 1)
341 printf(" %d calls to getit() at %d usec each\n",
342 getit_calls, (n + 5) / getit_calls);
343#endif
344}
345
346static void
347sysbeepstop(void *chan)
348{
349 ppi_spkr_off(); /* disable counter1 output to speaker */
350 timer_spkr_release();
351 beeping = 0;
352}
353
354int
355sysbeep(int pitch, int period)
356{
357 int x = splclock();
358
359 if (timer_spkr_acquire())
360 if (!beeping) {
361 /* Something else owns it. */
362 splx(x);
363 return (-1); /* XXX Should be EBUSY, but nobody cares anyway. */
364 }
365 mtx_lock_spin(&clock_lock);
366 spkr_set_pitch(pitch);
367 mtx_unlock_spin(&clock_lock);
368 if (!beeping) {
369 /* enable counter1 output to speaker */
370 ppi_spkr_on();
371 beeping = period;
372 timeout(sysbeepstop, (void *)NULL, period);
373 }
374 splx(x);
375 return (0);
376}
377
378static u_int
379calibrate_clocks(void)
380{
381 int timeout;
382 u_int count, prev_count, tot_count;
383 u_short sec, start_sec;
384
385 if (bootverbose)
386 printf("Calibrating clock(s) ... ");
387 /* Check ARTIC. */
388 if (!(PC98_SYSTEM_PARAMETER(0x458) & 0x80) &&
389 !(PC98_SYSTEM_PARAMETER(0x45b) & 0x04))
390 goto fail;
391 timeout = 100000000;
392
393 /* Read the ARTIC. */
394 sec = inw(0x5e);
395
396 /* Wait for the ARTIC to changes. */
397 start_sec = sec;
398 for (;;) {
399 sec = inw(0x5e);
400 if (sec != start_sec)
401 break;
402 if (--timeout == 0)
403 goto fail;
404 }
405
406 /* Start keeping track of the i8254 counter. */
407 prev_count = getit();
408 if (prev_count == 0 || prev_count > timer0_max_count)
409 goto fail;
410 tot_count = 0;
411
412 start_sec = sec;
413 for (;;) {
414 sec = inw(0x5e);
415 count = getit();
416 if (count == 0 || count > timer0_max_count)
417 goto fail;
418 if (count > prev_count)
419 tot_count += prev_count - (count - timer0_max_count);
420 else
421 tot_count += prev_count - count;
422 prev_count = count;
423 if ((sec == start_sec + 1200) || /* 1200 = 307.2KHz >> 8 */
424 (sec < start_sec &&
425 (u_int)sec + 0x10000 == (u_int)start_sec + 1200))
426 break;
427 if (--timeout == 0)
428 goto fail;
429 }
430
431 if (bootverbose) {
432 printf("i8254 clock: %u Hz\n", tot_count);
433 }
434 return (tot_count);
435
436fail:
437 if (bootverbose)
438 printf("failed, using default i8254 clock of %u Hz\n",
439 timer_freq);
440 return (timer_freq);
441}
442
443static void
444set_timer_freq(u_int freq, int intr_freq)
445{
446 int new_timer0_real_max_count;
447
448 i8254_timecounter.tc_frequency = freq;
449 mtx_lock_spin(&clock_lock);
450 timer_freq = freq;
451 if (using_lapic_timer)
452 new_timer0_real_max_count = 0x10000;
453 else
454 new_timer0_real_max_count = TIMER_DIV(intr_freq);
455 if (new_timer0_real_max_count != timer0_real_max_count) {
456 timer0_real_max_count = new_timer0_real_max_count;
457 if (timer0_real_max_count == 0x10000)
458 timer0_max_count = 0xffff;
459 else
460 timer0_max_count = timer0_real_max_count;
461 outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
462 outb(TIMER_CNTR0, timer0_real_max_count & 0xff);
463 outb(TIMER_CNTR0, timer0_real_max_count >> 8);
464 }
465 mtx_unlock_spin(&clock_lock);
466}
467
468static void
469i8254_restore(void)
470{
471
472 mtx_lock_spin(&clock_lock);
473 outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
474 outb(TIMER_CNTR0, timer0_real_max_count & 0xff);
475 outb(TIMER_CNTR0, timer0_real_max_count >> 8);
476 mtx_unlock_spin(&clock_lock);
477}
478
479
480/*
481 * Restore all the timers non-atomically (XXX: should be atomically).
482 *
483 * This function is called from pmtimer_resume() to restore all the timers.
484 * This should not be necessary, but there are broken laptops that do not
485 * restore all the timers on resume.
486 */
487void
488timer_restore(void)
489{
490
491 i8254_restore(); /* restore timer_freq and hz */
492}
493
494/* This is separate from startrtclock() so that it can be called early. */
495void
496i8254_init(void)
497{
498
499 mtx_init(&clock_lock, "clk", NULL, MTX_SPIN | MTX_NOPROFILE);
500
501 if (pc98_machine_type & M_8M)
502 timer_freq = 1996800L; /* 1.9968 MHz */
503 else
504 timer_freq = 2457600L; /* 2.4576 MHz */
505
506 set_timer_freq(timer_freq, hz);
507}
508
509void
510startrtclock()
511{
512 u_int delta, freq;
513
514 freq = calibrate_clocks();
515#ifdef CLK_CALIBRATION_LOOP
516 if (bootverbose) {
517 printf(
518 "Press a key on the console to abort clock calibration\n");
519 while (cncheckc() == -1)
520 calibrate_clocks();
521 }
522#endif
523
524 /*
525 * Use the calibrated i8254 frequency if it seems reasonable.
526 * Otherwise use the default, and don't use the calibrated i586
527 * frequency.
528 */
529 delta = freq > timer_freq ? freq - timer_freq : timer_freq - freq;
530 if (delta < timer_freq / 100) {
531#ifndef CLK_USE_I8254_CALIBRATION
532 if (bootverbose)
533 printf(
534"CLK_USE_I8254_CALIBRATION not specified - using default frequency\n");
535 freq = timer_freq;
536#endif
537 timer_freq = freq;
538 } else {
539 if (bootverbose)
540 printf(
541 "%d Hz differs from default of %d Hz by more than 1%%\n",
542 freq, timer_freq);
543 }
544
545 set_timer_freq(timer_freq, hz);
546 tc_init(&i8254_timecounter);
547
548 init_TSC();
549}
550
551static void
552rtc_serialcombit(int i)
553{
554 outb(IO_RTC, ((i&0x01)<<5)|0x07);
555 DELAY(1);
556 outb(IO_RTC, ((i&0x01)<<5)|0x17);
557 DELAY(1);
558 outb(IO_RTC, ((i&0x01)<<5)|0x07);
559 DELAY(1);
560}
561
562static void
563rtc_serialcom(int i)
564{
565 rtc_serialcombit(i&0x01);
566 rtc_serialcombit((i&0x02)>>1);
567 rtc_serialcombit((i&0x04)>>2);
568 rtc_serialcombit((i&0x08)>>3);
569 outb(IO_RTC, 0x07);
570 DELAY(1);
571 outb(IO_RTC, 0x0f);
572 DELAY(1);
573 outb(IO_RTC, 0x07);
574 DELAY(1);
575}
576
577static void
578rtc_outb(int val)
579{
580 int s;
581 int sa = 0;
582
583 for (s=0;s<8;s++) {
584 sa = ((val >> s) & 0x01) ? 0x27 : 0x07;
585 outb(IO_RTC, sa); /* set DI & CLK 0 */
586 DELAY(1);
587 outb(IO_RTC, sa | 0x10); /* CLK 1 */
588 DELAY(1);
589 }
590 outb(IO_RTC, sa & 0xef); /* CLK 0 */
591}
592
593static int
594rtc_inb(void)
595{
596 int s;
597 int sa = 0;
598
599 for (s=0;s<8;s++) {
600 sa |= ((inb(0x33) & 0x01) << s);
601 outb(IO_RTC, 0x17); /* CLK 1 */
602 DELAY(1);
603 outb(IO_RTC, 0x07); /* CLK 0 */
604 DELAY(2);
605 }
606 return sa;
607}
608
609/*
610 * Initialize the time of day register, based on the time base which is, e.g.
611 * from a filesystem.
612 */
613void
614inittodr(time_t base)
615{
616 struct timespec ts;
617 struct clocktime ct;
618 int i;
619
620 if (base) {
621 ts.tv_sec = base;
622 ts.tv_nsec = 0;
623 tc_setclock(&ts);
624 }
625
626 rtc_serialcom(0x03); /* Time Read */
627 rtc_serialcom(0x01); /* Register shift command. */
628 DELAY(20);
629
630 ct.nsec = 0;
631 ct.sec = bcd2bin(rtc_inb() & 0xff); /* sec */
632 ct.min = bcd2bin(rtc_inb() & 0xff); /* min */
633 ct.hour = bcd2bin(rtc_inb() & 0xff); /* hour */
634 ct.day = bcd2bin(rtc_inb() & 0xff); /* date */
635 i = rtc_inb();
636 ct.dow = i & 0x0f; /* dow */
637 ct.mon = (i >> 4) & 0x0f; /* month */
638 ct.year = bcd2bin(rtc_inb() & 0xff) + 1900; /* year */
639 if (ct.year < 1995)
640 ct.year += 100;
641 clock_ct_to_ts(&ct, &ts);
642 ts.tv_sec += utc_offset();
643 tc_setclock(&ts);
644}
645
646/*
647 * Write system time back to RTC
648 */
649void
650resettodr()
651{
652 struct timespec ts;
653 struct clocktime ct;
654
655 if (disable_rtc_set)
656 return;
657
658 getnanotime(&ts);
659 ts.tv_sec -= utc_offset();
660 clock_ts_to_ct(&ts, &ct);
661
662 rtc_serialcom(0x01); /* Register shift command. */
663
664 rtc_outb(bin2bcd(ct.sec)); /* Write back Seconds */
665 rtc_outb(bin2bcd(ct.min)); /* Write back Minutes */
666 rtc_outb(bin2bcd(ct.hour)); /* Write back Hours */
667
668 rtc_outb(bin2bcd(ct.day)); /* Write back Day */
669 rtc_outb((ct.mon << 4) | ct.dow); /* Write back Month and DOW */
670 rtc_outb(bin2bcd(ct.year % 100)); /* Write back Year */
671
672 rtc_serialcom(0x02); /* Time set & Counter hold command. */
673 rtc_serialcom(0x00); /* Register hold command. */
674}
675
676
677/*
678 * Start both clocks running.
679 */
680void
681cpu_initclocks()
682{
683
684#ifdef DEV_APIC
685 using_lapic_timer = lapic_setup_clock();
686#endif
687 /*
688 * If we aren't using the local APIC timer to drive the kernel
689 * clocks, setup the interrupt handler for the 8254 timer 0 so
690 * that it can drive hardclock(). Otherwise, change the 8254
691 * timecounter to user a simpler algorithm.
692 */
693 if (!using_lapic_timer) {
694 intr_add_handler("clk", 0, (driver_filter_t *)clkintr, NULL,
695 NULL, INTR_TYPE_CLK, NULL);
696 i8254_intsrc = intr_lookup_source(0);
697 if (i8254_intsrc != NULL)
698 i8254_pending =
699 i8254_intsrc->is_pic->pic_source_pending;
700 } else {
701 i8254_timecounter.tc_get_timecount =
702 i8254_simple_get_timecount;
703 i8254_timecounter.tc_counter_mask = 0xffff;
704 set_timer_freq(timer_freq, hz);
705 }
706
707 init_TSC_tc();
708}
709
710void
711cpu_startprofclock(void)
712{
713}
714
715void
716cpu_stopprofclock(void)
717{
718}
719
720static int
721sysctl_machdep_i8254_freq(SYSCTL_HANDLER_ARGS)
722{
723 int error;
724 u_int freq;
725
726 /*
727 * Use `i8254' instead of `timer' in external names because `timer'
728 * is is too generic. Should use it everywhere.
729 */
730 freq = timer_freq;
731 error = sysctl_handle_int(oidp, &freq, 0, req);
732 if (error == 0 && req->newptr != NULL)
733 set_timer_freq(freq, hz);
734 return (error);
735}
736
737SYSCTL_PROC(_machdep, OID_AUTO, i8254_freq, CTLTYPE_INT | CTLFLAG_RW,
738 0, sizeof(u_int), sysctl_machdep_i8254_freq, "IU", "");
739
740static unsigned
741i8254_simple_get_timecount(struct timecounter *tc)
742{
743
744 return (timer0_max_count - getit());
745}
746
747static unsigned
748i8254_get_timecount(struct timecounter *tc)
749{
750 u_int count;
751 u_int high, low;
752 u_int eflags;
753
754 eflags = read_eflags();
755 mtx_lock_spin(&clock_lock);
756
757 /* Select timer0 and latch counter value. */
758 outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
759
760 low = inb(TIMER_CNTR0);
761 high = inb(TIMER_CNTR0);
762 count = timer0_max_count - ((high << 8) | low);
763 if (count < i8254_lastcount ||
764 (!i8254_ticked && (clkintr_pending ||
765 ((count < 20 || (!(eflags & PSL_I) && count < timer0_max_count / 2u)) &&
766 i8254_pending != NULL && i8254_pending(i8254_intsrc))))) {
767 i8254_ticked = 1;
768 i8254_offset += timer0_max_count;
769 }
770 i8254_lastcount = count;
771 count += i8254_offset;
772 mtx_unlock_spin(&clock_lock);
773 return (count);
774}
775
776#ifdef DEV_ISA
777/*
778 * Attach to the ISA PnP descriptors for the timer and realtime clock.
779 */
780static struct isa_pnp_id attimer_ids[] = {
781 { 0x0001d041 /* PNP0100 */, "AT timer" },
782 { 0x000bd041 /* PNP0B00 */, "AT realtime clock" },
783 { 0 }
784};
785
786static int
787attimer_probe(device_t dev)
788{
789 int result;
790
791 if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, attimer_ids)) <= 0)
792 device_quiet(dev);
793 return(result);
794}
795
796static int
797attimer_attach(device_t dev)
798{
799 return(0);
800}
801
802static device_method_t attimer_methods[] = {
803 /* Device interface */
804 DEVMETHOD(device_probe, attimer_probe),
805 DEVMETHOD(device_attach, attimer_attach),
806 DEVMETHOD(device_detach, bus_generic_detach),
807 DEVMETHOD(device_shutdown, bus_generic_shutdown),
808 DEVMETHOD(device_suspend, bus_generic_suspend), /* XXX stop statclock? */
809 DEVMETHOD(device_resume, bus_generic_resume), /* XXX restart statclock? */
810 { 0, 0 }
811};
812
813static driver_t attimer_driver = {
814 "attimer",
815 attimer_methods,
816 1, /* no softc */
817};
818
819static devclass_t attimer_devclass;
820
821DRIVER_MODULE(attimer, isa, attimer_driver, attimer_devclass, 0, 0);
822#endif /* DEV_ISA */
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz and Don Ahn.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * from: @(#)clock.c 7.2 (Berkeley) 5/12/91
33 */
34
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD: head/sys/pc98/cbus/pcrtc.c 170289 2007-06-04 18:25:08Z dwmalone $");
37
38/*
39 * Routines to handle clock hardware.
40 */
41
42/*
43 * inittodr, settodr and support routines written
44 * by Christoph Robitschko <chmr@edvz.tu-graz.ac.at>
45 *
46 * reintroduced and updated by Chris Stenton <chris@gnome.co.uk> 8/10/94
47 */
48
49/*
50 * modified for PC98 by Kakefuda
51 */
52
53#include "opt_apic.h"
54#include "opt_clock.h"
55#include "opt_isa.h"
56#include "opt_mca.h"
57
58#include <sys/param.h>
59#include <sys/systm.h>
60#include <sys/bus.h>
61#include <sys/clock.h>
62#include <sys/lock.h>
63#include <sys/kdb.h>
64#include <sys/mutex.h>
65#include <sys/proc.h>
66#include <sys/time.h>
67#include <sys/timetc.h>
68#include <sys/kernel.h>
69#include <sys/limits.h>
70#include <sys/module.h>
71#include <sys/sysctl.h>
72#include <sys/cons.h>
73#include <sys/power.h>
74
75#include <machine/clock.h>
76#include <machine/cpu.h>
77#include <machine/cputypes.h>
78#include <machine/frame.h>
79#include <machine/intr_machdep.h>
80#include <machine/md_var.h>
81#include <machine/psl.h>
82#ifdef DEV_APIC
83#include <machine/apicvar.h>
84#endif
85#include <machine/specialreg.h>
86#include <machine/ppireg.h>
87#include <machine/timerreg.h>
88
89#include <i386/isa/icu.h>
90#include <pc98/cbus/cbus.h>
91#include <pc98/pc98/pc98_machdep.h>
92#ifdef DEV_ISA
93#include <isa/isavar.h>
94#endif
95
96#define TIMER_DIV(x) ((timer_freq + (x) / 2) / (x))
97
98int clkintr_pending;
99int pscnt = 1;
100int psdiv = 1;
101int statclock_disable;
102#ifndef TIMER_FREQ
103#define TIMER_FREQ 2457600
104#endif
105u_int timer_freq = TIMER_FREQ;
106int timer0_max_count;
107int timer0_real_max_count;
108
109static int beeping = 0;
110static struct mtx clock_lock;
111static struct intsrc *i8254_intsrc;
112static u_int32_t i8254_lastcount;
113static u_int32_t i8254_offset;
114static int (*i8254_pending)(struct intsrc *);
115static int i8254_ticked;
116static int using_lapic_timer;
117
118/* Values for timerX_state: */
119#define RELEASED 0
120#define RELEASE_PENDING 1
121#define ACQUIRED 2
122#define ACQUIRE_PENDING 3
123
124static u_char timer1_state;
125static u_char timer2_state;
126static void rtc_serialcombit(int);
127static void rtc_serialcom(int);
128static int rtc_inb(void);
129static void rtc_outb(int);
130
131static unsigned i8254_get_timecount(struct timecounter *tc);
132static unsigned i8254_simple_get_timecount(struct timecounter *tc);
133static void set_timer_freq(u_int freq, int intr_freq);
134
135static struct timecounter i8254_timecounter = {
136 i8254_get_timecount, /* get_timecount */
137 0, /* no poll_pps */
138 ~0u, /* counter_mask */
139 0, /* frequency */
140 "i8254", /* name */
141 0 /* quality */
142};
143
144static int
145clkintr(struct trapframe *frame)
146{
147
148 if (timecounter->tc_get_timecount == i8254_get_timecount) {
149 mtx_lock_spin(&clock_lock);
150 if (i8254_ticked)
151 i8254_ticked = 0;
152 else {
153 i8254_offset += timer0_max_count;
154 i8254_lastcount = 0;
155 }
156 clkintr_pending = 0;
157 mtx_unlock_spin(&clock_lock);
158 }
159 KASSERT(!using_lapic_timer, ("clk interrupt enabled with lapic timer"));
160 hardclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
161 return (FILTER_HANDLED);
162}
163
164int
165acquire_timer1(int mode)
166{
167
168 if (timer1_state != RELEASED)
169 return (-1);
170 timer1_state = ACQUIRED;
171
172 /*
173 * This access to the timer registers is as atomic as possible
174 * because it is a single instruction. We could do better if we
175 * knew the rate. Use of splclock() limits glitches to 10-100us,
176 * and this is probably good enough for timer2, so we aren't as
177 * careful with it as with timer0.
178 */
179 outb(TIMER_MODE, TIMER_SEL1 | (mode & 0x3f));
180
181 return (0);
182}
183
184int
185acquire_timer2(int mode)
186{
187
188 if (timer2_state != RELEASED)
189 return (-1);
190 timer2_state = ACQUIRED;
191
192 /*
193 * This access to the timer registers is as atomic as possible
194 * because it is a single instruction. We could do better if we
195 * knew the rate. Use of splclock() limits glitches to 10-100us,
196 * and this is probably good enough for timer2, so we aren't as
197 * careful with it as with timer0.
198 */
199 outb(TIMER_MODE, TIMER_SEL2 | (mode & 0x3f));
200
201 return (0);
202}
203
204int
205release_timer1()
206{
207
208 if (timer1_state != ACQUIRED)
209 return (-1);
210 timer1_state = RELEASED;
211 outb(TIMER_MODE, TIMER_SEL1 | TIMER_SQWAVE | TIMER_16BIT);
212 return (0);
213}
214
215int
216release_timer2()
217{
218
219 if (timer2_state != ACQUIRED)
220 return (-1);
221 timer2_state = RELEASED;
222 outb(TIMER_MODE, TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT);
223 return (0);
224}
225
226
227static int
228getit(void)
229{
230 int high, low;
231
232 mtx_lock_spin(&clock_lock);
233
234 /* Select timer0 and latch counter value. */
235 outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
236
237 low = inb(TIMER_CNTR0);
238 high = inb(TIMER_CNTR0);
239
240 mtx_unlock_spin(&clock_lock);
241 return ((high << 8) | low);
242}
243
244/*
245 * Wait "n" microseconds.
246 * Relies on timer 1 counting down from (timer_freq / hz)
247 * Note: timer had better have been programmed before this is first used!
248 */
249void
250DELAY(int n)
251{
252 int delta, prev_tick, tick, ticks_left;
253
254#ifdef DELAYDEBUG
255 int getit_calls = 1;
256 int n1;
257 static int state = 0;
258
259 if (state == 0) {
260 state = 1;
261 for (n1 = 1; n1 <= 10000000; n1 *= 10)
262 DELAY(n1);
263 state = 2;
264 }
265 if (state == 1)
266 printf("DELAY(%d)...", n);
267#endif
268 /*
269 * Read the counter first, so that the rest of the setup overhead is
270 * counted. Guess the initial overhead is 20 usec (on most systems it
271 * takes about 1.5 usec for each of the i/o's in getit(). The loop
272 * takes about 6 usec on a 486/33 and 13 usec on a 386/20. The
273 * multiplications and divisions to scale the count take a while).
274 *
275 * However, if ddb is active then use a fake counter since reading
276 * the i8254 counter involves acquiring a lock. ddb must not do
277 * locking for many reasons, but it calls here for at least atkbd
278 * input.
279 */
280#ifdef KDB
281 if (kdb_active)
282 prev_tick = 1;
283 else
284#endif
285 prev_tick = getit();
286 n -= 0; /* XXX actually guess no initial overhead */
287 /*
288 * Calculate (n * (timer_freq / 1e6)) without using floating point
289 * and without any avoidable overflows.
290 */
291 if (n <= 0)
292 ticks_left = 0;
293 else if (n < 256)
294 /*
295 * Use fixed point to avoid a slow division by 1000000.
296 * 39099 = 1193182 * 2^15 / 10^6 rounded to nearest.
297 * 2^15 is the first power of 2 that gives exact results
298 * for n between 0 and 256.
299 */
300 ticks_left = ((u_int)n * 39099 + (1 << 15) - 1) >> 15;
301 else
302 /*
303 * Don't bother using fixed point, although gcc-2.7.2
304 * generates particularly poor code for the long long
305 * division, since even the slow way will complete long
306 * before the delay is up (unless we're interrupted).
307 */
308 ticks_left = ((u_int)n * (long long)timer_freq + 999999)
309 / 1000000;
310
311 while (ticks_left > 0) {
312#ifdef KDB
313 if (kdb_active) {
314 outb(0x5f, 0);
315 tick = prev_tick - 1;
316 if (tick <= 0)
317 tick = timer0_max_count;
318 } else
319#endif
320 tick = getit();
321#ifdef DELAYDEBUG
322 ++getit_calls;
323#endif
324 delta = prev_tick - tick;
325 prev_tick = tick;
326 if (delta < 0) {
327 delta += timer0_max_count;
328 /*
329 * Guard against timer0_max_count being wrong.
330 * This shouldn't happen in normal operation,
331 * but it may happen if set_timer_freq() is
332 * traced.
333 */
334 if (delta < 0)
335 delta = 0;
336 }
337 ticks_left -= delta;
338 }
339#ifdef DELAYDEBUG
340 if (state == 1)
341 printf(" %d calls to getit() at %d usec each\n",
342 getit_calls, (n + 5) / getit_calls);
343#endif
344}
345
346static void
347sysbeepstop(void *chan)
348{
349 ppi_spkr_off(); /* disable counter1 output to speaker */
350 timer_spkr_release();
351 beeping = 0;
352}
353
354int
355sysbeep(int pitch, int period)
356{
357 int x = splclock();
358
359 if (timer_spkr_acquire())
360 if (!beeping) {
361 /* Something else owns it. */
362 splx(x);
363 return (-1); /* XXX Should be EBUSY, but nobody cares anyway. */
364 }
365 mtx_lock_spin(&clock_lock);
366 spkr_set_pitch(pitch);
367 mtx_unlock_spin(&clock_lock);
368 if (!beeping) {
369 /* enable counter1 output to speaker */
370 ppi_spkr_on();
371 beeping = period;
372 timeout(sysbeepstop, (void *)NULL, period);
373 }
374 splx(x);
375 return (0);
376}
377
378static u_int
379calibrate_clocks(void)
380{
381 int timeout;
382 u_int count, prev_count, tot_count;
383 u_short sec, start_sec;
384
385 if (bootverbose)
386 printf("Calibrating clock(s) ... ");
387 /* Check ARTIC. */
388 if (!(PC98_SYSTEM_PARAMETER(0x458) & 0x80) &&
389 !(PC98_SYSTEM_PARAMETER(0x45b) & 0x04))
390 goto fail;
391 timeout = 100000000;
392
393 /* Read the ARTIC. */
394 sec = inw(0x5e);
395
396 /* Wait for the ARTIC to changes. */
397 start_sec = sec;
398 for (;;) {
399 sec = inw(0x5e);
400 if (sec != start_sec)
401 break;
402 if (--timeout == 0)
403 goto fail;
404 }
405
406 /* Start keeping track of the i8254 counter. */
407 prev_count = getit();
408 if (prev_count == 0 || prev_count > timer0_max_count)
409 goto fail;
410 tot_count = 0;
411
412 start_sec = sec;
413 for (;;) {
414 sec = inw(0x5e);
415 count = getit();
416 if (count == 0 || count > timer0_max_count)
417 goto fail;
418 if (count > prev_count)
419 tot_count += prev_count - (count - timer0_max_count);
420 else
421 tot_count += prev_count - count;
422 prev_count = count;
423 if ((sec == start_sec + 1200) || /* 1200 = 307.2KHz >> 8 */
424 (sec < start_sec &&
425 (u_int)sec + 0x10000 == (u_int)start_sec + 1200))
426 break;
427 if (--timeout == 0)
428 goto fail;
429 }
430
431 if (bootverbose) {
432 printf("i8254 clock: %u Hz\n", tot_count);
433 }
434 return (tot_count);
435
436fail:
437 if (bootverbose)
438 printf("failed, using default i8254 clock of %u Hz\n",
439 timer_freq);
440 return (timer_freq);
441}
442
443static void
444set_timer_freq(u_int freq, int intr_freq)
445{
446 int new_timer0_real_max_count;
447
448 i8254_timecounter.tc_frequency = freq;
449 mtx_lock_spin(&clock_lock);
450 timer_freq = freq;
451 if (using_lapic_timer)
452 new_timer0_real_max_count = 0x10000;
453 else
454 new_timer0_real_max_count = TIMER_DIV(intr_freq);
455 if (new_timer0_real_max_count != timer0_real_max_count) {
456 timer0_real_max_count = new_timer0_real_max_count;
457 if (timer0_real_max_count == 0x10000)
458 timer0_max_count = 0xffff;
459 else
460 timer0_max_count = timer0_real_max_count;
461 outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
462 outb(TIMER_CNTR0, timer0_real_max_count & 0xff);
463 outb(TIMER_CNTR0, timer0_real_max_count >> 8);
464 }
465 mtx_unlock_spin(&clock_lock);
466}
467
468static void
469i8254_restore(void)
470{
471
472 mtx_lock_spin(&clock_lock);
473 outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
474 outb(TIMER_CNTR0, timer0_real_max_count & 0xff);
475 outb(TIMER_CNTR0, timer0_real_max_count >> 8);
476 mtx_unlock_spin(&clock_lock);
477}
478
479
480/*
481 * Restore all the timers non-atomically (XXX: should be atomically).
482 *
483 * This function is called from pmtimer_resume() to restore all the timers.
484 * This should not be necessary, but there are broken laptops that do not
485 * restore all the timers on resume.
486 */
487void
488timer_restore(void)
489{
490
491 i8254_restore(); /* restore timer_freq and hz */
492}
493
494/* This is separate from startrtclock() so that it can be called early. */
495void
496i8254_init(void)
497{
498
499 mtx_init(&clock_lock, "clk", NULL, MTX_SPIN | MTX_NOPROFILE);
500
501 if (pc98_machine_type & M_8M)
502 timer_freq = 1996800L; /* 1.9968 MHz */
503 else
504 timer_freq = 2457600L; /* 2.4576 MHz */
505
506 set_timer_freq(timer_freq, hz);
507}
508
509void
510startrtclock()
511{
512 u_int delta, freq;
513
514 freq = calibrate_clocks();
515#ifdef CLK_CALIBRATION_LOOP
516 if (bootverbose) {
517 printf(
518 "Press a key on the console to abort clock calibration\n");
519 while (cncheckc() == -1)
520 calibrate_clocks();
521 }
522#endif
523
524 /*
525 * Use the calibrated i8254 frequency if it seems reasonable.
526 * Otherwise use the default, and don't use the calibrated i586
527 * frequency.
528 */
529 delta = freq > timer_freq ? freq - timer_freq : timer_freq - freq;
530 if (delta < timer_freq / 100) {
531#ifndef CLK_USE_I8254_CALIBRATION
532 if (bootverbose)
533 printf(
534"CLK_USE_I8254_CALIBRATION not specified - using default frequency\n");
535 freq = timer_freq;
536#endif
537 timer_freq = freq;
538 } else {
539 if (bootverbose)
540 printf(
541 "%d Hz differs from default of %d Hz by more than 1%%\n",
542 freq, timer_freq);
543 }
544
545 set_timer_freq(timer_freq, hz);
546 tc_init(&i8254_timecounter);
547
548 init_TSC();
549}
550
551static void
552rtc_serialcombit(int i)
553{
554 outb(IO_RTC, ((i&0x01)<<5)|0x07);
555 DELAY(1);
556 outb(IO_RTC, ((i&0x01)<<5)|0x17);
557 DELAY(1);
558 outb(IO_RTC, ((i&0x01)<<5)|0x07);
559 DELAY(1);
560}
561
562static void
563rtc_serialcom(int i)
564{
565 rtc_serialcombit(i&0x01);
566 rtc_serialcombit((i&0x02)>>1);
567 rtc_serialcombit((i&0x04)>>2);
568 rtc_serialcombit((i&0x08)>>3);
569 outb(IO_RTC, 0x07);
570 DELAY(1);
571 outb(IO_RTC, 0x0f);
572 DELAY(1);
573 outb(IO_RTC, 0x07);
574 DELAY(1);
575}
576
577static void
578rtc_outb(int val)
579{
580 int s;
581 int sa = 0;
582
583 for (s=0;s<8;s++) {
584 sa = ((val >> s) & 0x01) ? 0x27 : 0x07;
585 outb(IO_RTC, sa); /* set DI & CLK 0 */
586 DELAY(1);
587 outb(IO_RTC, sa | 0x10); /* CLK 1 */
588 DELAY(1);
589 }
590 outb(IO_RTC, sa & 0xef); /* CLK 0 */
591}
592
593static int
594rtc_inb(void)
595{
596 int s;
597 int sa = 0;
598
599 for (s=0;s<8;s++) {
600 sa |= ((inb(0x33) & 0x01) << s);
601 outb(IO_RTC, 0x17); /* CLK 1 */
602 DELAY(1);
603 outb(IO_RTC, 0x07); /* CLK 0 */
604 DELAY(2);
605 }
606 return sa;
607}
608
609/*
610 * Initialize the time of day register, based on the time base which is, e.g.
611 * from a filesystem.
612 */
613void
614inittodr(time_t base)
615{
616 struct timespec ts;
617 struct clocktime ct;
618 int i;
619
620 if (base) {
621 ts.tv_sec = base;
622 ts.tv_nsec = 0;
623 tc_setclock(&ts);
624 }
625
626 rtc_serialcom(0x03); /* Time Read */
627 rtc_serialcom(0x01); /* Register shift command. */
628 DELAY(20);
629
630 ct.nsec = 0;
631 ct.sec = bcd2bin(rtc_inb() & 0xff); /* sec */
632 ct.min = bcd2bin(rtc_inb() & 0xff); /* min */
633 ct.hour = bcd2bin(rtc_inb() & 0xff); /* hour */
634 ct.day = bcd2bin(rtc_inb() & 0xff); /* date */
635 i = rtc_inb();
636 ct.dow = i & 0x0f; /* dow */
637 ct.mon = (i >> 4) & 0x0f; /* month */
638 ct.year = bcd2bin(rtc_inb() & 0xff) + 1900; /* year */
639 if (ct.year < 1995)
640 ct.year += 100;
641 clock_ct_to_ts(&ct, &ts);
642 ts.tv_sec += utc_offset();
643 tc_setclock(&ts);
644}
645
646/*
647 * Write system time back to RTC
648 */
649void
650resettodr()
651{
652 struct timespec ts;
653 struct clocktime ct;
654
655 if (disable_rtc_set)
656 return;
657
658 getnanotime(&ts);
659 ts.tv_sec -= utc_offset();
660 clock_ts_to_ct(&ts, &ct);
661
662 rtc_serialcom(0x01); /* Register shift command. */
663
664 rtc_outb(bin2bcd(ct.sec)); /* Write back Seconds */
665 rtc_outb(bin2bcd(ct.min)); /* Write back Minutes */
666 rtc_outb(bin2bcd(ct.hour)); /* Write back Hours */
667
668 rtc_outb(bin2bcd(ct.day)); /* Write back Day */
669 rtc_outb((ct.mon << 4) | ct.dow); /* Write back Month and DOW */
670 rtc_outb(bin2bcd(ct.year % 100)); /* Write back Year */
671
672 rtc_serialcom(0x02); /* Time set & Counter hold command. */
673 rtc_serialcom(0x00); /* Register hold command. */
674}
675
676
677/*
678 * Start both clocks running.
679 */
680void
681cpu_initclocks()
682{
683
684#ifdef DEV_APIC
685 using_lapic_timer = lapic_setup_clock();
686#endif
687 /*
688 * If we aren't using the local APIC timer to drive the kernel
689 * clocks, setup the interrupt handler for the 8254 timer 0 so
690 * that it can drive hardclock(). Otherwise, change the 8254
691 * timecounter to user a simpler algorithm.
692 */
693 if (!using_lapic_timer) {
694 intr_add_handler("clk", 0, (driver_filter_t *)clkintr, NULL,
695 NULL, INTR_TYPE_CLK, NULL);
696 i8254_intsrc = intr_lookup_source(0);
697 if (i8254_intsrc != NULL)
698 i8254_pending =
699 i8254_intsrc->is_pic->pic_source_pending;
700 } else {
701 i8254_timecounter.tc_get_timecount =
702 i8254_simple_get_timecount;
703 i8254_timecounter.tc_counter_mask = 0xffff;
704 set_timer_freq(timer_freq, hz);
705 }
706
707 init_TSC_tc();
708}
709
710void
711cpu_startprofclock(void)
712{
713}
714
715void
716cpu_stopprofclock(void)
717{
718}
719
720static int
721sysctl_machdep_i8254_freq(SYSCTL_HANDLER_ARGS)
722{
723 int error;
724 u_int freq;
725
726 /*
727 * Use `i8254' instead of `timer' in external names because `timer'
728 * is is too generic. Should use it everywhere.
729 */
730 freq = timer_freq;
731 error = sysctl_handle_int(oidp, &freq, 0, req);
732 if (error == 0 && req->newptr != NULL)
733 set_timer_freq(freq, hz);
734 return (error);
735}
736
737SYSCTL_PROC(_machdep, OID_AUTO, i8254_freq, CTLTYPE_INT | CTLFLAG_RW,
738 0, sizeof(u_int), sysctl_machdep_i8254_freq, "IU", "");
739
740static unsigned
741i8254_simple_get_timecount(struct timecounter *tc)
742{
743
744 return (timer0_max_count - getit());
745}
746
747static unsigned
748i8254_get_timecount(struct timecounter *tc)
749{
750 u_int count;
751 u_int high, low;
752 u_int eflags;
753
754 eflags = read_eflags();
755 mtx_lock_spin(&clock_lock);
756
757 /* Select timer0 and latch counter value. */
758 outb(TIMER_MODE, TIMER_SEL0 | TIMER_LATCH);
759
760 low = inb(TIMER_CNTR0);
761 high = inb(TIMER_CNTR0);
762 count = timer0_max_count - ((high << 8) | low);
763 if (count < i8254_lastcount ||
764 (!i8254_ticked && (clkintr_pending ||
765 ((count < 20 || (!(eflags & PSL_I) && count < timer0_max_count / 2u)) &&
766 i8254_pending != NULL && i8254_pending(i8254_intsrc))))) {
767 i8254_ticked = 1;
768 i8254_offset += timer0_max_count;
769 }
770 i8254_lastcount = count;
771 count += i8254_offset;
772 mtx_unlock_spin(&clock_lock);
773 return (count);
774}
775
776#ifdef DEV_ISA
777/*
778 * Attach to the ISA PnP descriptors for the timer and realtime clock.
779 */
780static struct isa_pnp_id attimer_ids[] = {
781 { 0x0001d041 /* PNP0100 */, "AT timer" },
782 { 0x000bd041 /* PNP0B00 */, "AT realtime clock" },
783 { 0 }
784};
785
786static int
787attimer_probe(device_t dev)
788{
789 int result;
790
791 if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, attimer_ids)) <= 0)
792 device_quiet(dev);
793 return(result);
794}
795
796static int
797attimer_attach(device_t dev)
798{
799 return(0);
800}
801
802static device_method_t attimer_methods[] = {
803 /* Device interface */
804 DEVMETHOD(device_probe, attimer_probe),
805 DEVMETHOD(device_attach, attimer_attach),
806 DEVMETHOD(device_detach, bus_generic_detach),
807 DEVMETHOD(device_shutdown, bus_generic_shutdown),
808 DEVMETHOD(device_suspend, bus_generic_suspend), /* XXX stop statclock? */
809 DEVMETHOD(device_resume, bus_generic_resume), /* XXX restart statclock? */
810 { 0, 0 }
811};
812
813static driver_t attimer_driver = {
814 "attimer",
815 attimer_methods,
816 1, /* no softc */
817};
818
819static devclass_t attimer_devclass;
820
821DRIVER_MODULE(attimer, isa, attimer_driver, attimer_devclass, 0, 0);
822#endif /* DEV_ISA */