xref: /netbsd-src/sys/arch/amiga/dev/clock.c (revision 0dd5877adce57db949b16ae963e5a6831cccdfb6)
1 /*	$NetBSD: clock.c,v 1.38 2002/01/28 09:56:53 aymeric 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 1.38 2002/01/28 09:56:53 aymeric 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 
76 /*
77  * Machine-dependent clock routines.
78  *
79  * Startrtclock restarts the real-time clock, which provides
80  * hardclock interrupts to kern_clock.c.
81  *
82  * Inittodr initializes the time of day hardware which provides
83  * date functions.
84  *
85  * Resettodr restores the time of day hardware after a time change.
86  *
87  * A note on the real-time clock:
88  * We actually load the clock with CLK_INTERVAL-1 instead of CLK_INTERVAL.
89  * This is because the counter decrements to zero after N+1 enabled clock
90  * periods where N is the value loaded into the counter.
91  */
92 
93 int clockmatch(struct device *, struct cfdata *, void *);
94 void clockattach(struct device *, struct device *, void *);
95 void cpu_initclocks(void);
96 void calibrate_delay(struct device *);
97 
98 struct cfattach clock_ca = {
99 	sizeof(struct device), clockmatch, clockattach
100 };
101 
102 int
103 clockmatch(struct device *pdp, struct cfdata *cfp, void *auxp)
104 {
105 	if (matchname("clock", auxp))
106 		return(1);
107 	return(0);
108 }
109 
110 /*
111  * Start the real-time clock.
112  */
113 void
114 clockattach(struct device *pdp, struct device *dp, void *auxp)
115 {
116 	char *clockchip;
117 	unsigned short interval;
118 #ifdef DRACO
119 	u_char dracorev;
120 #endif
121 
122 	if (eclockfreq == 0)
123 		eclockfreq = 715909;	/* guess NTSC */
124 
125 	CLK_INTERVAL = (eclockfreq / 100);
126 
127 #ifdef DRACO
128 	dracorev = is_draco();
129 	if (dracorev >= 4) {
130 		CLK_INTERVAL = (eclockfreq / 700);
131 		clockchip = "QuickLogic";
132 	} else if (dracorev) {
133 		clockcia = (struct CIA *)CIAAbase;
134 		clockchip = "CIA A";
135 	} else
136 #endif
137 	{
138 		clockcia = (struct CIA *)CIABbase;
139 		clockchip = "CIA B";
140 	}
141 
142 	if (dp)
143 		printf(": %s system hz %d hardware hz %d\n", clockchip, hz,
144 #ifdef DRACO
145 		dracorev >= 4 ? eclockfreq / 7 : eclockfreq);
146 #else
147 		eclockfreq);
148 #endif
149 
150 #ifdef DRACO
151 	if (dracorev >= 4) {
152 		/*
153 		 * can't preload anything beforehand, timer is free_running;
154 		 * but need this for delay calibration.
155 		 */
156 
157 		draco_ioct->io_timerlo = CLK_INTERVAL & 0xff;
158 		draco_ioct->io_timerhi = CLK_INTERVAL >> 8;
159 
160 		calibrate_delay(dp);
161 
162 		return;
163 	}
164 #endif
165 	/*
166 	 * stop timer A
167 	 */
168 	clockcia->cra = clockcia->cra & 0xc0;
169 	clockcia->icr = 1 << 0;		/* disable timer A interrupt */
170 	interval = clockcia->icr;		/* and make sure it's clear */
171 
172 	/*
173 	 * load interval into registers.
174          * the clocks run at NTSC: 715.909kHz or PAL: 709.379kHz
175 	 * supprort for PAL WHEN?!?! XXX
176 	 */
177 	interval = CLK_INTERVAL - 1;
178 
179 	/*
180 	 * order of setting is important !
181 	 */
182 	clockcia->talo = interval & 0xff;
183 	clockcia->tahi = interval >> 8;
184 	/*
185 	 * start timer A in continuous mode
186 	 */
187 	clockcia->cra = (clockcia->cra & 0xc0) | 1;
188 
189 	calibrate_delay(dp);
190 }
191 
192 /*
193  * Calibrate delay loop.
194  * We use two iterations because we don't have enough bits to do a factor of
195  * 8 with better than 1%.
196  *
197  * XXX Note that we MUST stay below 1 tick if using clkread(), even for
198  * underestimated values of delaydivisor.
199  *
200  * XXX the "ns" below is only correct for a shift of 10 bits, and even then
201  * off by 2.4%
202  */
203 
204 void
205 calibrate_delay(struct device *dp)
206 {
207 	unsigned long t1, t2;
208 	extern u_int32_t delaydivisor;
209 		/* XXX this should be defined elsewhere */
210 
211 	if (dp)
212 		printf("Calibrating delay loop... ");
213 
214 	do {
215 		t1 = clkread();
216 		delay(1024);
217 		t2 = clkread();
218 	} while (t2 <= t1);
219 	t2 -= t1;
220 	delaydivisor = (delaydivisor * t2 + 1023) >> 10;
221 #ifdef DEBUG
222 	if (dp)
223 		printf("\ndiff %ld us, new divisor %u/1024 us\n", t2,
224 		    delaydivisor);
225 	do {
226 		t1 = clkread();
227 		delay(1024);
228 		t2 = clkread();
229 	} while (t2 <= t1);
230 	t2 -= t1;
231 	delaydivisor = (delaydivisor * t2 + 1023) >> 10;
232 	if (dp)
233 		printf("diff %ld us, new divisor %u/1024 us\n", t2,
234 		    delaydivisor);
235 #endif
236 	do {
237 		t1 = clkread();
238 		delay(1024);
239 		t2 = clkread();
240 	} while (t2 <= t1);
241 	t2 -= t1;
242 	delaydivisor = (delaydivisor * t2 + 1023) >> 10;
243 #ifdef DEBUG
244 	if (dp)
245 		printf("diff %ld us, new divisor ", t2);
246 #endif
247 	if (dp)
248 		printf("%u/1024 us\n", delaydivisor);
249 }
250 
251 void
252 cpu_initclocks(void)
253 {
254 #ifdef DRACO
255 	unsigned char dracorev;
256 	dracorev = is_draco();
257 	if (dracorev >= 4) {
258 		draco_ioct->io_timerlo = CLK_INTERVAL & 0xFF;
259 		draco_ioct->io_timerhi = CLK_INTERVAL >> 8;
260 		draco_ioct->io_timerrst = 0;	/* any value resets */
261 		single_inst_bset_b(draco_ioct->io_status2, DRSTAT2_TMRINTENA);
262 
263 		return;
264 	}
265 #endif
266 	/*
267 	 * enable interrupts for timer A
268 	 */
269 	clockcia->icr = (1<<7) | (1<<0);
270 
271 	/*
272 	 * start timer A in continuous shot mode
273 	 */
274 	clockcia->cra = (clockcia->cra & 0xc0) | 1;
275 
276 	/*
277 	 * and globally enable interrupts for ciab
278 	 */
279 #ifdef DRACO
280 	if (dracorev)		/* we use cia a on DraCo */
281 		single_inst_bset_b(*draco_intena, DRIRQ_INT2);
282 	else
283 #endif
284 		custom.intena = INTF_SETCLR | INTF_EXTER;
285 
286 }
287 
288 void
289 setstatclockrate(int hz)
290 {
291 }
292 
293 /*
294  * Returns number of usec since last recorded clock "tick"
295  * (i.e. clock interrupt).
296  */
297 u_long
298 clkread(void)
299 {
300 	u_int interval;
301 	u_char hi, hi2, lo;
302 
303 #ifdef DRACO
304 	if (is_draco() >= 4) {
305 		hi2 = draco_ioct->io_chiprev;	/* latch timer */
306 		hi = draco_ioct->io_timerhi;
307 		lo = draco_ioct->io_timerlo;
308 		interval = ((hi<<8) | lo);
309 		if (interval > CLK_INTERVAL)	/* timer underflow */
310 			interval = 65536 + CLK_INTERVAL - interval;
311 		else
312 			interval = CLK_INTERVAL - interval;
313 
314 	} else
315 #endif
316 	{
317 		hi  = clockcia->tahi;
318 		lo  = clockcia->talo;
319 		hi2 = clockcia->tahi;
320 		if (hi != hi2) {
321 			lo = clockcia->talo;
322 			hi = hi2;
323 		}
324 
325 		interval = (CLK_INTERVAL - 1) - ((hi<<8) | lo);
326 
327 		/*
328 		 * should read ICR and if there's an int pending, adjust
329 		 * interval. However, since reading ICR clears the interrupt,
330 		 * we'd lose a hardclock int, and this is not tolerable.
331 		 */
332 	}
333 
334 	return((interval * tick) / CLK_INTERVAL);
335 }
336 
337 #if notyet
338 
339 /* implement this later. I'd suggest using both timers in CIA-A, they're
340    not yet used. */
341 
342 #include "clock.h"
343 #if NCLOCK > 0
344 /*
345  * /dev/clock: mappable high resolution timer.
346  *
347  * This code implements a 32-bit recycling counter (with a 4 usec period)
348  * using timers 2 & 3 on the 6840 clock chip.  The counter can be mapped
349  * RO into a user's address space to achieve low overhead (no system calls),
350  * high-precision timing.
351  *
352  * Note that timer 3 is also used for the high precision profiling timer
353  * (PROFTIMER code above).  Care should be taken when both uses are
354  * configured as only a token effort is made to avoid conflicting use.
355  */
356 #include <sys/proc.h>
357 #include <sys/resourcevar.h>
358 #include <sys/ioctl.h>
359 #include <sys/malloc.h>
360 #include <uvm/uvm_extern.h>
361 #include <amiga/amiga/clockioctl.h>
362 #include <sys/specdev.h>
363 #include <sys/vnode.h>
364 #include <sys/mman.h>
365 
366 int clockon = 0;		/* non-zero if high-res timer enabled */
367 #ifdef PROFTIMER
368 int  profprocs = 0;		/* # of procs using profiling timer */
369 #endif
370 #ifdef DEBUG
371 int clockdebug = 0;
372 #endif
373 
374 /*ARGSUSED*/
375 int
376 clockopen(dev_t dev, int flags)
377 {
378 #ifdef PROFTIMER
379 #ifdef PROF
380 	/*
381 	 * Kernel profiling enabled, give up.
382 	 */
383 	if (profiling)
384 		return(EBUSY);
385 #endif
386 	/*
387 	 * If any user processes are profiling, give up.
388 	 */
389 	if (profprocs)
390 		return(EBUSY);
391 #endif
392 	if (!clockon) {
393 		startclock();
394 		clockon++;
395 	}
396 	return(0);
397 }
398 
399 /*ARGSUSED*/
400 int
401 clockclose(dev_t dev, int flags)
402 {
403 	(void) clockunmmap(dev, (caddr_t)0, curproc);	/* XXX */
404 	stopclock();
405 	clockon = 0;
406 	return(0);
407 }
408 
409 /*ARGSUSED*/
410 int
411 clockioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
412 {
413 	int error = 0;
414 
415 	switch (cmd) {
416 
417 	case CLOCKMAP:
418 		error = clockmmap(dev, (caddr_t *)data, p);
419 		break;
420 
421 	case CLOCKUNMAP:
422 		error = clockunmmap(dev, *(caddr_t *)data, p);
423 		break;
424 
425 	case CLOCKGETRES:
426 		*(int *)data = CLK_RESOLUTION;
427 		break;
428 
429 	default:
430 		error = EINVAL;
431 		break;
432 	}
433 	return(error);
434 }
435 
436 /*ARGSUSED*/
437 void
438 clockmap(dev_t dev, int off, int prot)
439 {
440 	return((off + (INTIOBASE+CLKBASE+CLKSR-1)) >> PGSHIFT);
441 }
442 
443 int
444 clockmmap(dev_t dev, caddr_t *addrp, struct proc *p)
445 {
446 	int error;
447 	struct vnode vn;
448 	struct specinfo si;
449 	int flags;
450 
451 	flags = MAP_FILE|MAP_SHARED;
452 	if (*addrp)
453 		flags |= MAP_FIXED;
454 	else
455 		*addrp = (caddr_t)0x1000000;	/* XXX */
456 	vn.v_type = VCHR;			/* XXX */
457 	vn.v_specinfo = &si;			/* XXX */
458 	vn.v_rdev = dev;			/* XXX */
459 	error = vm_mmap(&p->p_vmspace->vm_map, (vm_offset_t *)addrp,
460 			PAGE_SIZE, VM_PROT_ALL, flags, (caddr_t)&vn, 0);
461 	return(error);
462 }
463 
464 int
465 clockunmmap(dev_t dev, caddr_t addr, struct proc *p)
466 {
467 	int rv;
468 
469 	if (addr == 0)
470 		return(EINVAL);		/* XXX: how do we deal with this? */
471 	uvm_deallocate(p->p_vmspace->vm_map, (vm_offset_t)addr, PAGE_SIZE);
472 	return 0;
473 }
474 
475 void
476 startclock(void)
477 {
478 	register struct clkreg *clk = (struct clkreg *)clkstd[0];
479 
480 	clk->clk_msb2 = -1; clk->clk_lsb2 = -1;
481 	clk->clk_msb3 = -1; clk->clk_lsb3 = -1;
482 
483 	clk->clk_cr2 = CLK_CR3;
484 	clk->clk_cr3 = CLK_OENAB|CLK_8BIT;
485 	clk->clk_cr2 = CLK_CR1;
486 	clk->clk_cr1 = CLK_IENAB;
487 }
488 
489 void
490 stopclock(void)
491 {
492 	register struct clkreg *clk = (struct clkreg *)clkstd[0];
493 
494 	clk->clk_cr2 = CLK_CR3;
495 	clk->clk_cr3 = 0;
496 	clk->clk_cr2 = CLK_CR1;
497 	clk->clk_cr1 = CLK_IENAB;
498 }
499 #endif
500 
501 #endif
502 
503 
504 #ifdef PROFTIMER
505 /*
506  * This code allows the amiga kernel to use one of the extra timers on
507  * the clock chip for profiling, instead of the regular system timer.
508  * The advantage of this is that the profiling timer can be turned up to
509  * a higher interrupt rate, giving finer resolution timing. The profclock
510  * routine is called from the lev6intr in locore, and is a specialized
511  * routine that calls addupc. The overhead then is far less than if
512  * hardclock/softclock was called. Further, the context switch code in
513  * locore has been changed to turn the profile clock on/off when switching
514  * into/out of a process that is profiling (startprofclock/stopprofclock).
515  * This reduces the impact of the profiling clock on other users, and might
516  * possibly increase the accuracy of the profiling.
517  */
518 int  profint   = PRF_INTERVAL;	/* Clock ticks between interrupts */
519 int  profscale = 0;		/* Scale factor from sys clock to prof clock */
520 char profon    = 0;		/* Is profiling clock on? */
521 
522 /* profon values - do not change, locore.s assumes these values */
523 #define PRF_NONE	0x00
524 #define	PRF_USER	0x01
525 #define	PRF_KERNEL	0x80
526 
527 void
528 initprofclock(void)
529 {
530 #if NCLOCK > 0
531 	struct proc *p = curproc;		/* XXX */
532 
533 	/*
534 	 * If the high-res timer is running, force profiling off.
535 	 * Unfortunately, this gets reflected back to the user not as
536 	 * an error but as a lack of results.
537 	 */
538 	if (clockon) {
539 		p->p_stats->p_prof.pr_scale = 0;
540 		return;
541 	}
542 	/*
543 	 * Keep track of the number of user processes that are profiling
544 	 * by checking the scale value.
545 	 *
546 	 * XXX: this all assumes that the profiling code is well behaved;
547 	 * i.e. profil() is called once per process with pcscale non-zero
548 	 * to turn it on, and once with pcscale zero to turn it off.
549 	 * Also assumes you don't do any forks or execs.  Oh well, there
550 	 * is always adb...
551 	 */
552 	if (p->p_stats->p_prof.pr_scale)
553 		profprocs++;
554 	else
555 		profprocs--;
556 #endif
557 	/*
558 	 * The profile interrupt interval must be an even divisor
559 	 * of the CLK_INTERVAL so that scaling from a system clock
560 	 * tick to a profile clock tick is possible using integer math.
561 	 */
562 	if (profint > CLK_INTERVAL || (CLK_INTERVAL % profint) != 0)
563 		profint = CLK_INTERVAL;
564 	profscale = CLK_INTERVAL / profint;
565 }
566 
567 void
568 startprofclock(void)
569 {
570   unsigned short interval;
571 
572   /* stop timer B */
573   clockcia->crb = clockcia->crb & 0xc0;
574 
575   /* load interval into registers.
576      the clocks run at NTSC: 715.909kHz or PAL: 709.379kHz */
577 
578   interval = profint - 1;
579 
580   /* order of setting is important ! */
581   clockcia->tblo = interval & 0xff;
582   clockcia->tbhi = interval >> 8;
583 
584   /* enable interrupts for timer B */
585   clockcia->icr = (1<<7) | (1<<1);
586 
587   /* start timer B in continuous shot mode */
588   clockcia->crb = (clockcia->crb & 0xc0) | 1;
589 }
590 
591 void
592 stopprofclock(void)
593 {
594   /* stop timer B */
595   clockcia->crb = clockcia->crb & 0xc0;
596 }
597 
598 #ifdef PROF
599 /*
600  * profclock() is expanded in line in lev6intr() unless profiling kernel.
601  * Assumes it is called with clock interrupts blocked.
602  */
603 void
604 profclock(caddr_t pc, int ps)
605 {
606 	/*
607 	 * Came from user mode.
608 	 * If this process is being profiled record the tick.
609 	 */
610 	if (USERMODE(ps)) {
611 		if (p->p_stats.p_prof.pr_scale)
612 			addupc(pc, &curproc->p_stats.p_prof, 1);
613 	}
614 	/*
615 	 * Came from kernel (supervisor) mode.
616 	 * If we are profiling the kernel, record the tick.
617 	 */
618 	else if (profiling < 2) {
619 		register int s = pc - s_lowpc;
620 
621 		if (s < s_textsize)
622 			kcount[s / (HISTFRACTION * sizeof (*kcount))]++;
623 	}
624 	/*
625 	 * Kernel profiling was on but has been disabled.
626 	 * Mark as no longer profiling kernel and if all profiling done,
627 	 * disable the clock.
628 	 */
629 	if (profiling && (profon & PRF_KERNEL)) {
630 		profon &= ~PRF_KERNEL;
631 		if (profon == PRF_NONE)
632 			stopprofclock();
633 	}
634 }
635 #endif
636 #endif
637 
638 /*
639  * Initialize the time of day register, based on the time base which is, e.g.
640  * from a filesystem.
641  */
642 void
643 inittodr(time_t base)
644 {
645 	struct timeval tvbuf;
646 
647 	tvbuf.tv_usec = 0;
648 	tvbuf.tv_sec = base;	/* assume no battery clock exists */
649 
650 	if (ugettod == NULL)
651 		printf("WARNING: no battery clock\n");
652 	else {
653 		ugettod(&tvbuf);
654 		tvbuf.tv_sec +=  rtc_offset * 60;
655 	}
656 
657 	if (tvbuf.tv_sec < base) {
658 		printf("WARNING: bad date in battery clock\n");
659 		tvbuf.tv_sec = base;
660 	}
661 
662 	time = tvbuf;
663 }
664 
665 void
666 resettodr(void)
667 {
668 	struct timeval tvbuf;
669 
670 	if (!usettod)
671 		return;
672 
673 	tvbuf = time;
674 
675 	tvbuf.tv_sec -= rtc_offset * 60;
676 
677 	if (!usettod(&tvbuf))
678 		printf("Cannot set battery backed clock\n");
679 }
680