xref: /netbsd-src/sys/arch/amiga/dev/clock.c (revision 001c68bd94f75ce9270b69227c4199fbf34ee396)
1 /*	$NetBSD: clock.c,v 1.41 2002/10/02 04:55:49 thorpej Exp $ */
2 
3 /*
4  * Copyright (c) 1988 University of Utah.
5  * Copyright (c) 1982, 1990 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * the Systems Programming Group of the University of Utah Computer
10  * Science Department.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  * from: Utah $Hdr: clock.c 1.18 91/01/21$
41  *
42  *	@(#)clock.c	7.6 (Berkeley) 5/7/91
43  */
44 
45 #include <sys/cdefs.h>
46 __KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.41 2002/10/02 04:55:49 thorpej Exp $");
47 
48 #include <sys/param.h>
49 #include <sys/kernel.h>
50 #include <sys/device.h>
51 #include <sys/systm.h>
52 #include <machine/psl.h>
53 #include <machine/cpu.h>
54 #include <amiga/amiga/device.h>
55 #include <amiga/amiga/custom.h>
56 #include <amiga/amiga/cia.h>
57 #ifdef DRACO
58 #include <amiga/amiga/drcustom.h>
59 #include <m68k/include/asm_single.h>
60 #endif
61 #include <amiga/dev/rtc.h>
62 #include <amiga/dev/zbusvar.h>
63 
64 #if defined(PROF) && defined(PROFTIMER)
65 #include <sys/PROF.h>
66 #endif
67 
68 /* the clocks run at NTSC: 715.909kHz or PAL: 709.379kHz.
69    We're using a 100 Hz clock. */
70 
71 #define CLK_INTERVAL amiga_clk_interval
72 int amiga_clk_interval;
73 int eclockfreq;
74 struct CIA *clockcia;
75 int (*usettod)(struct timeval *);
76 int (*ugettod)(struct timeval *);
77 
78 /*
79  * Machine-dependent clock routines.
80  *
81  * Startrtclock restarts the real-time clock, which provides
82  * hardclock interrupts to kern_clock.c.
83  *
84  * Inittodr initializes the time of day hardware which provides
85  * date functions.
86  *
87  * Resettodr restores the time of day hardware after a time change.
88  *
89  * A note on the real-time clock:
90  * We actually load the clock with CLK_INTERVAL-1 instead of CLK_INTERVAL.
91  * This is because the counter decrements to zero after N+1 enabled clock
92  * periods where N is the value loaded into the counter.
93  */
94 
95 int clockmatch(struct device *, struct cfdata *, void *);
96 void clockattach(struct device *, struct device *, void *);
97 void cpu_initclocks(void);
98 void calibrate_delay(struct device *);
99 
100 CFATTACH_DECL(clock, sizeof(struct device),
101     clockmatch, clockattach, NULL, NULL);
102 
103 int
104 clockmatch(struct device *pdp, struct cfdata *cfp, void *auxp)
105 {
106 	if (matchname("clock", auxp))
107 		return(1);
108 	return(0);
109 }
110 
111 /*
112  * Start the real-time clock.
113  */
114 void
115 clockattach(struct device *pdp, struct device *dp, void *auxp)
116 {
117 	char *clockchip;
118 	unsigned short interval;
119 #ifdef DRACO
120 	u_char dracorev;
121 #endif
122 
123 	if (eclockfreq == 0)
124 		eclockfreq = 715909;	/* guess NTSC */
125 
126 	CLK_INTERVAL = (eclockfreq / 100);
127 
128 #ifdef DRACO
129 	dracorev = is_draco();
130 	if (dracorev >= 4) {
131 		CLK_INTERVAL = (eclockfreq / 700);
132 		clockchip = "QuickLogic";
133 	} else if (dracorev) {
134 		clockcia = (struct CIA *)CIAAbase;
135 		clockchip = "CIA A";
136 	} else
137 #endif
138 	{
139 		clockcia = (struct CIA *)CIABbase;
140 		clockchip = "CIA B";
141 	}
142 
143 	if (dp)
144 		printf(": %s system hz %d hardware hz %d\n", clockchip, hz,
145 #ifdef DRACO
146 		dracorev >= 4 ? eclockfreq / 7 : eclockfreq);
147 #else
148 		eclockfreq);
149 #endif
150 
151 #ifdef DRACO
152 	if (dracorev >= 4) {
153 		/*
154 		 * can't preload anything beforehand, timer is free_running;
155 		 * but need this for delay calibration.
156 		 */
157 
158 		draco_ioct->io_timerlo = CLK_INTERVAL & 0xff;
159 		draco_ioct->io_timerhi = CLK_INTERVAL >> 8;
160 
161 		calibrate_delay(dp);
162 
163 		return;
164 	}
165 #endif
166 	/*
167 	 * stop timer A
168 	 */
169 	clockcia->cra = clockcia->cra & 0xc0;
170 	clockcia->icr = 1 << 0;		/* disable timer A interrupt */
171 	interval = clockcia->icr;		/* and make sure it's clear */
172 
173 	/*
174 	 * load interval into registers.
175          * the clocks run at NTSC: 715.909kHz or PAL: 709.379kHz
176 	 * supprort for PAL WHEN?!?! XXX
177 	 */
178 	interval = CLK_INTERVAL - 1;
179 
180 	/*
181 	 * order of setting is important !
182 	 */
183 	clockcia->talo = interval & 0xff;
184 	clockcia->tahi = interval >> 8;
185 	/*
186 	 * start timer A in continuous mode
187 	 */
188 	clockcia->cra = (clockcia->cra & 0xc0) | 1;
189 
190 	calibrate_delay(dp);
191 }
192 
193 /*
194  * Calibrate delay loop.
195  * We use two iterations because we don't have enough bits to do a factor of
196  * 8 with better than 1%.
197  *
198  * XXX Note that we MUST stay below 1 tick if using clkread(), even for
199  * underestimated values of delaydivisor.
200  *
201  * XXX the "ns" below is only correct for a shift of 10 bits, and even then
202  * off by 2.4%
203  */
204 
205 void
206 calibrate_delay(struct device *dp)
207 {
208 	unsigned long t1, t2;
209 	extern u_int32_t delaydivisor;
210 		/* XXX this should be defined elsewhere */
211 
212 	if (dp)
213 		printf("Calibrating delay loop... ");
214 
215 	do {
216 		t1 = clkread();
217 		delay(1024);
218 		t2 = clkread();
219 	} while (t2 <= t1);
220 	t2 -= t1;
221 	delaydivisor = (delaydivisor * t2 + 1023) >> 10;
222 #ifdef DEBUG
223 	if (dp)
224 		printf("\ndiff %ld us, new divisor %u/1024 us\n", t2,
225 		    delaydivisor);
226 	do {
227 		t1 = clkread();
228 		delay(1024);
229 		t2 = clkread();
230 	} while (t2 <= t1);
231 	t2 -= t1;
232 	delaydivisor = (delaydivisor * t2 + 1023) >> 10;
233 	if (dp)
234 		printf("diff %ld us, new divisor %u/1024 us\n", t2,
235 		    delaydivisor);
236 #endif
237 	do {
238 		t1 = clkread();
239 		delay(1024);
240 		t2 = clkread();
241 	} while (t2 <= t1);
242 	t2 -= t1;
243 	delaydivisor = (delaydivisor * t2 + 1023) >> 10;
244 #ifdef DEBUG
245 	if (dp)
246 		printf("diff %ld us, new divisor ", t2);
247 #endif
248 	if (dp)
249 		printf("%u/1024 us\n", delaydivisor);
250 }
251 
252 void
253 cpu_initclocks(void)
254 {
255 #ifdef DRACO
256 	unsigned char dracorev;
257 	dracorev = is_draco();
258 	if (dracorev >= 4) {
259 		draco_ioct->io_timerlo = CLK_INTERVAL & 0xFF;
260 		draco_ioct->io_timerhi = CLK_INTERVAL >> 8;
261 		draco_ioct->io_timerrst = 0;	/* any value resets */
262 		single_inst_bset_b(draco_ioct->io_status2, DRSTAT2_TMRINTENA);
263 
264 		return;
265 	}
266 #endif
267 	/*
268 	 * enable interrupts for timer A
269 	 */
270 	clockcia->icr = (1<<7) | (1<<0);
271 
272 	/*
273 	 * start timer A in continuous shot mode
274 	 */
275 	clockcia->cra = (clockcia->cra & 0xc0) | 1;
276 
277 	/*
278 	 * and globally enable interrupts for ciab
279 	 */
280 #ifdef DRACO
281 	if (dracorev)		/* we use cia a on DraCo */
282 		single_inst_bset_b(*draco_intena, DRIRQ_INT2);
283 	else
284 #endif
285 		custom.intena = INTF_SETCLR | INTF_EXTER;
286 
287 }
288 
289 void
290 setstatclockrate(int hz)
291 {
292 }
293 
294 /*
295  * Returns number of usec since last recorded clock "tick"
296  * (i.e. clock interrupt).
297  */
298 u_long
299 clkread(void)
300 {
301 	u_int interval;
302 	u_char hi, hi2, lo;
303 
304 #ifdef DRACO
305 	if (is_draco() >= 4) {
306 		hi2 = draco_ioct->io_chiprev;	/* latch timer */
307 		hi = draco_ioct->io_timerhi;
308 		lo = draco_ioct->io_timerlo;
309 		interval = ((hi<<8) | lo);
310 		if (interval > CLK_INTERVAL)	/* timer underflow */
311 			interval = 65536 + CLK_INTERVAL - interval;
312 		else
313 			interval = CLK_INTERVAL - interval;
314 
315 	} else
316 #endif
317 	{
318 		hi  = clockcia->tahi;
319 		lo  = clockcia->talo;
320 		hi2 = clockcia->tahi;
321 		if (hi != hi2) {
322 			lo = clockcia->talo;
323 			hi = hi2;
324 		}
325 
326 		interval = (CLK_INTERVAL - 1) - ((hi<<8) | lo);
327 
328 		/*
329 		 * should read ICR and if there's an int pending, adjust
330 		 * interval. However, since reading ICR clears the interrupt,
331 		 * we'd lose a hardclock int, and this is not tolerable.
332 		 */
333 	}
334 
335 	return((interval * tick) / CLK_INTERVAL);
336 }
337 
338 #if notyet
339 
340 /* implement this later. I'd suggest using both timers in CIA-A, they're
341    not yet used. */
342 
343 #include "clock.h"
344 #if NCLOCK > 0
345 /*
346  * /dev/clock: mappable high resolution timer.
347  *
348  * This code implements a 32-bit recycling counter (with a 4 usec period)
349  * using timers 2 & 3 on the 6840 clock chip.  The counter can be mapped
350  * RO into a user's address space to achieve low overhead (no system calls),
351  * high-precision timing.
352  *
353  * Note that timer 3 is also used for the high precision profiling timer
354  * (PROFTIMER code above).  Care should be taken when both uses are
355  * configured as only a token effort is made to avoid conflicting use.
356  */
357 #include <sys/proc.h>
358 #include <sys/resourcevar.h>
359 #include <sys/ioctl.h>
360 #include <sys/malloc.h>
361 #include <uvm/uvm_extern.h>
362 #include <amiga/amiga/clockioctl.h>
363 #include <sys/specdev.h>
364 #include <sys/vnode.h>
365 #include <sys/mman.h>
366 
367 int clockon = 0;		/* non-zero if high-res timer enabled */
368 #ifdef PROFTIMER
369 int  profprocs = 0;		/* # of procs using profiling timer */
370 #endif
371 #ifdef DEBUG
372 int clockdebug = 0;
373 #endif
374 
375 /*ARGSUSED*/
376 int
377 clockopen(dev_t dev, int flags)
378 {
379 #ifdef PROFTIMER
380 #ifdef PROF
381 	/*
382 	 * Kernel profiling enabled, give up.
383 	 */
384 	if (profiling)
385 		return(EBUSY);
386 #endif
387 	/*
388 	 * If any user processes are profiling, give up.
389 	 */
390 	if (profprocs)
391 		return(EBUSY);
392 #endif
393 	if (!clockon) {
394 		startclock();
395 		clockon++;
396 	}
397 	return(0);
398 }
399 
400 /*ARGSUSED*/
401 int
402 clockclose(dev_t dev, int flags)
403 {
404 	(void) clockunmmap(dev, (caddr_t)0, curproc);	/* XXX */
405 	stopclock();
406 	clockon = 0;
407 	return(0);
408 }
409 
410 /*ARGSUSED*/
411 int
412 clockioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
413 {
414 	int error = 0;
415 
416 	switch (cmd) {
417 
418 	case CLOCKMAP:
419 		error = clockmmap(dev, (caddr_t *)data, p);
420 		break;
421 
422 	case CLOCKUNMAP:
423 		error = clockunmmap(dev, *(caddr_t *)data, p);
424 		break;
425 
426 	case CLOCKGETRES:
427 		*(int *)data = CLK_RESOLUTION;
428 		break;
429 
430 	default:
431 		error = EINVAL;
432 		break;
433 	}
434 	return(error);
435 }
436 
437 /*ARGSUSED*/
438 void
439 clockmap(dev_t dev, int off, int prot)
440 {
441 	return((off + (INTIOBASE+CLKBASE+CLKSR-1)) >> PGSHIFT);
442 }
443 
444 int
445 clockmmap(dev_t dev, caddr_t *addrp, struct proc *p)
446 {
447 	int error;
448 	struct vnode vn;
449 	struct specinfo si;
450 	int flags;
451 
452 	flags = MAP_FILE|MAP_SHARED;
453 	if (*addrp)
454 		flags |= MAP_FIXED;
455 	else
456 		*addrp = (caddr_t)0x1000000;	/* XXX */
457 	vn.v_type = VCHR;			/* XXX */
458 	vn.v_specinfo = &si;			/* XXX */
459 	vn.v_rdev = dev;			/* XXX */
460 	error = vm_mmap(&p->p_vmspace->vm_map, (vm_offset_t *)addrp,
461 			PAGE_SIZE, VM_PROT_ALL, flags, (caddr_t)&vn, 0);
462 	return(error);
463 }
464 
465 int
466 clockunmmap(dev_t dev, caddr_t addr, struct proc *p)
467 {
468 	int rv;
469 
470 	if (addr == 0)
471 		return(EINVAL);		/* XXX: how do we deal with this? */
472 	uvm_deallocate(p->p_vmspace->vm_map, (vm_offset_t)addr, PAGE_SIZE);
473 	return 0;
474 }
475 
476 void
477 startclock(void)
478 {
479 	register struct clkreg *clk = (struct clkreg *)clkstd[0];
480 
481 	clk->clk_msb2 = -1; clk->clk_lsb2 = -1;
482 	clk->clk_msb3 = -1; clk->clk_lsb3 = -1;
483 
484 	clk->clk_cr2 = CLK_CR3;
485 	clk->clk_cr3 = CLK_OENAB|CLK_8BIT;
486 	clk->clk_cr2 = CLK_CR1;
487 	clk->clk_cr1 = CLK_IENAB;
488 }
489 
490 void
491 stopclock(void)
492 {
493 	register struct clkreg *clk = (struct clkreg *)clkstd[0];
494 
495 	clk->clk_cr2 = CLK_CR3;
496 	clk->clk_cr3 = 0;
497 	clk->clk_cr2 = CLK_CR1;
498 	clk->clk_cr1 = CLK_IENAB;
499 }
500 #endif
501 
502 #endif
503 
504 
505 #ifdef PROFTIMER
506 /*
507  * This code allows the amiga kernel to use one of the extra timers on
508  * the clock chip for profiling, instead of the regular system timer.
509  * The advantage of this is that the profiling timer can be turned up to
510  * a higher interrupt rate, giving finer resolution timing. The profclock
511  * routine is called from the lev6intr in locore, and is a specialized
512  * routine that calls addupc. The overhead then is far less than if
513  * hardclock/softclock was called. Further, the context switch code in
514  * locore has been changed to turn the profile clock on/off when switching
515  * into/out of a process that is profiling (startprofclock/stopprofclock).
516  * This reduces the impact of the profiling clock on other users, and might
517  * possibly increase the accuracy of the profiling.
518  */
519 int  profint   = PRF_INTERVAL;	/* Clock ticks between interrupts */
520 int  profscale = 0;		/* Scale factor from sys clock to prof clock */
521 char profon    = 0;		/* Is profiling clock on? */
522 
523 /* profon values - do not change, locore.s assumes these values */
524 #define PRF_NONE	0x00
525 #define	PRF_USER	0x01
526 #define	PRF_KERNEL	0x80
527 
528 void
529 initprofclock(void)
530 {
531 #if NCLOCK > 0
532 	struct proc *p = curproc;		/* XXX */
533 
534 	/*
535 	 * If the high-res timer is running, force profiling off.
536 	 * Unfortunately, this gets reflected back to the user not as
537 	 * an error but as a lack of results.
538 	 */
539 	if (clockon) {
540 		p->p_stats->p_prof.pr_scale = 0;
541 		return;
542 	}
543 	/*
544 	 * Keep track of the number of user processes that are profiling
545 	 * by checking the scale value.
546 	 *
547 	 * XXX: this all assumes that the profiling code is well behaved;
548 	 * i.e. profil() is called once per process with pcscale non-zero
549 	 * to turn it on, and once with pcscale zero to turn it off.
550 	 * Also assumes you don't do any forks or execs.  Oh well, there
551 	 * is always adb...
552 	 */
553 	if (p->p_stats->p_prof.pr_scale)
554 		profprocs++;
555 	else
556 		profprocs--;
557 #endif
558 	/*
559 	 * The profile interrupt interval must be an even divisor
560 	 * of the CLK_INTERVAL so that scaling from a system clock
561 	 * tick to a profile clock tick is possible using integer math.
562 	 */
563 	if (profint > CLK_INTERVAL || (CLK_INTERVAL % profint) != 0)
564 		profint = CLK_INTERVAL;
565 	profscale = CLK_INTERVAL / profint;
566 }
567 
568 void
569 startprofclock(void)
570 {
571   unsigned short interval;
572 
573   /* stop timer B */
574   clockcia->crb = clockcia->crb & 0xc0;
575 
576   /* load interval into registers.
577      the clocks run at NTSC: 715.909kHz or PAL: 709.379kHz */
578 
579   interval = profint - 1;
580 
581   /* order of setting is important ! */
582   clockcia->tblo = interval & 0xff;
583   clockcia->tbhi = interval >> 8;
584 
585   /* enable interrupts for timer B */
586   clockcia->icr = (1<<7) | (1<<1);
587 
588   /* start timer B in continuous shot mode */
589   clockcia->crb = (clockcia->crb & 0xc0) | 1;
590 }
591 
592 void
593 stopprofclock(void)
594 {
595   /* stop timer B */
596   clockcia->crb = clockcia->crb & 0xc0;
597 }
598 
599 #ifdef PROF
600 /*
601  * profclock() is expanded in line in lev6intr() unless profiling kernel.
602  * Assumes it is called with clock interrupts blocked.
603  */
604 void
605 profclock(caddr_t pc, int ps)
606 {
607 	/*
608 	 * Came from user mode.
609 	 * If this process is being profiled record the tick.
610 	 */
611 	if (USERMODE(ps)) {
612 		if (p->p_stats.p_prof.pr_scale)
613 			addupc(pc, &curproc->p_stats.p_prof, 1);
614 	}
615 	/*
616 	 * Came from kernel (supervisor) mode.
617 	 * If we are profiling the kernel, record the tick.
618 	 */
619 	else if (profiling < 2) {
620 		register int s = pc - s_lowpc;
621 
622 		if (s < s_textsize)
623 			kcount[s / (HISTFRACTION * sizeof (*kcount))]++;
624 	}
625 	/*
626 	 * Kernel profiling was on but has been disabled.
627 	 * Mark as no longer profiling kernel and if all profiling done,
628 	 * disable the clock.
629 	 */
630 	if (profiling && (profon & PRF_KERNEL)) {
631 		profon &= ~PRF_KERNEL;
632 		if (profon == PRF_NONE)
633 			stopprofclock();
634 	}
635 }
636 #endif
637 #endif
638 
639 /*
640  * Initialize the time of day register, based on the time base which is, e.g.
641  * from a filesystem.
642  */
643 void
644 inittodr(time_t base)
645 {
646 	struct timeval tvbuf;
647 
648 	tvbuf.tv_usec = 0;
649 	tvbuf.tv_sec = base;	/* assume no battery clock exists */
650 
651 	if (ugettod == NULL)
652 		printf("WARNING: no battery clock\n");
653 	else {
654 		ugettod(&tvbuf);
655 		tvbuf.tv_sec +=  rtc_offset * 60;
656 	}
657 
658 	if (tvbuf.tv_sec < base) {
659 		printf("WARNING: bad date in battery clock\n");
660 		tvbuf.tv_sec = base;
661 	}
662 
663 	time = tvbuf;
664 }
665 
666 void
667 resettodr(void)
668 {
669 	struct timeval tvbuf;
670 
671 	if (!usettod)
672 		return;
673 
674 	tvbuf = time;
675 
676 	tvbuf.tv_sec -= rtc_offset * 60;
677 
678 	if (!usettod(&tvbuf))
679 		printf("Cannot set battery backed clock\n");
680 }
681