xref: /netbsd/sys/arch/sparc/sparc/timer.c (revision 1ee1eb05)
1 /*	$NetBSD: timer.c,v 1.25 2010/01/03 23:03:21 mrg Exp $ */
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 1994 Gordon W. Ross
7  * Copyright (c) 1993 Adam Glass
8  * Copyright (c) 1996 Paul Kranenburg
9  * Copyright (c) 1996
10  * 	The President and Fellows of Harvard College. All rights reserved.
11  *
12  * This software was developed by the Computer Systems Engineering group
13  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
14  * contributed to Berkeley.
15  *
16  * All advertising materials mentioning features or use of this software
17  * must display the following acknowledgement:
18  *	This product includes software developed by Harvard University.
19  *	This product includes software developed by the University of
20  *	California, Lawrence Berkeley Laboratory.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  *
26  * 1. Redistributions of source code must retain the above copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *	This product includes software developed by the University of
34  *	California, Berkeley and its contributors.
35  *	This product includes software developed by Paul Kranenburg.
36  *	This product includes software developed by Harvard University.
37  * 4. Neither the name of the University nor the names of its contributors
38  *    may be used to endorse or promote products derived from this software
39  *    without specific prior written permission.
40  *
41  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  *	@(#)clock.c	8.1 (Berkeley) 6/11/93
54  */
55 
56 /*
57  * Kernel clocks provided by "timer" device.  The hardclock is provided by
58  * the timer register (aka system counter).  The statclock is provided by
59  * per CPU counter register(s) (aka processor counter(s)).
60  */
61 
62 #include <sys/cdefs.h>
63 __KERNEL_RCSID(0, "$NetBSD: timer.c,v 1.25 2010/01/03 23:03:21 mrg Exp $");
64 
65 #include <sys/param.h>
66 #include <sys/kernel.h>
67 #include <sys/device.h>
68 #include <sys/systm.h>
69 #include <sys/timetc.h>
70 
71 #include <machine/autoconf.h>
72 #include <machine/bus.h>
73 
74 #include <sparc/sparc/timerreg.h>
75 #include <sparc/sparc/timervar.h>
76 
77 static struct intrhand level10;
78 static struct intrhand level14;
79 
80 static u_int timer_get_timecount(struct timecounter *);
81 
82 /*
83  * timecounter local state
84  */
85 static struct counter {
86 	volatile u_int *cntreg;	/* counter register */
87 	u_int limit;		/* limit we count up to */
88 	u_int offset;		/* accumulated offet due to wraps */
89 	u_int shift;		/* scaling for valid bits */
90 	u_int mask;		/* valid bit mask */
91 } cntr;
92 
93 /*
94  * define timecounter
95  */
96 
97 static struct timecounter counter_timecounter = {
98 	timer_get_timecount,	/* get_timecount */
99 	0,			/* no poll_pps */
100 	~0u,			/* counter_mask */
101 	0,                      /* frequency - set at initialisation */
102 	"timer-counter",	/* name */
103 	100,			/* quality */
104 	&cntr			/* private reference */
105 };
106 
107 /*
108  * timer_get_timecount provide current counter value
109  */
110 static u_int
111 timer_get_timecount(struct timecounter *tc)
112 {
113 	struct counter *ctr = (struct counter *)tc->tc_priv;
114 
115 	u_int c, res, r;
116 	int s;
117 
118 
119 	s = splhigh();
120 
121 	res = c = *ctr->cntreg;
122 
123 	res  &= ~TMR_LIMIT;
124 
125 	if (c != res) {
126 		r = ctr->limit;
127 	} else {
128 		r = 0;
129 	}
130 
131 	res >>= ctr->shift;
132 	res  &= ctr->mask;
133 
134 	res += r + ctr->offset;
135 
136 	splx(s);
137 
138 	return res;
139 }
140 
141 void
142 tickle_tc(void)
143 {
144 	if (timecounter->tc_get_timecount == timer_get_timecount) {
145 		cntr.offset += cntr.limit;
146 	}
147 }
148 
149 /*
150  * sun4/sun4c/sun4m common timer attach code
151  */
152 void
153 timerattach(volatile int *cntreg, volatile int *limreg)
154 {
155 	u_int prec = 0, t0;
156 
157 	/*
158 	 * Calibrate delay() by tweaking the magic constant
159 	 * until a delay(100) actually reads (at least) 100 us on the clock.
160 	 * Note: sun4m clocks tick with 500ns periods.
161 	 */
162 	for (timerblurb = 1; ; timerblurb++) {
163 		volatile int discard;
164 		u_int t1;
165 
166 		/* Reset counter register by writing some large limit value */
167 		discard = *limreg;
168 		*limreg = tmr_ustolim(TMR_MASK-1);
169 
170 		t0 = *cntreg;
171 		delay(100);
172 		t1 = *cntreg;
173 
174 		prec |= (t0 ^ t1) | (*cntreg ^ *cntreg);
175 
176 		if (t1 & TMR_LIMIT)
177 			panic("delay calibration");
178 
179 		t0 = (t0 >> TMR_SHIFT) & TMR_MASK;
180 		t1 = (t1 >> TMR_SHIFT) & TMR_MASK;
181 
182 		if (t1 >= t0 + 100)
183 			break;
184 	}
185 
186 	/* find lowest active bit */
187 	for (t0 = 0; t0 < TMR_SHIFT; t0++)
188 		if ((1 << t0) & prec)
189 			break;
190 
191 	cntr.shift = t0;
192 	cntr.mask = (1 << (31-t0))-1;
193 	counter_timecounter.tc_frequency = 1000000 * (TMR_SHIFT - t0 + 1);
194 
195 	printf(": delay constant %d, frequency = %" PRIu64 " Hz\n", timerblurb, counter_timecounter.tc_frequency);
196 
197 #if defined(SUN4) || defined(SUN4C)
198 	if (CPU_ISSUN4 || CPU_ISSUN4C) {
199 		timer_init = timer_init_4;
200 		level10.ih_fun = clockintr_4;
201 		level14.ih_fun = statintr_4;
202 		cntr.limit = tmr_ustolim(tick);
203 	}
204 #endif
205 #if defined(SUN4M)
206 	if (CPU_ISSUN4M) {
207 		timer_init = timer_init_4m;
208 		level10.ih_fun = clockintr_4m;
209 		level14.ih_fun = statintr_4m;
210 		cntr.limit = tmr_ustolim4m(tick);
211 	}
212 #endif
213 	/* link interrupt handlers */
214 	intr_establish(10, 0, &level10, NULL, true);
215 	intr_establish(14, 0, &level14, NULL, true);
216 
217 	/* Establish a soft interrupt at a lower level for schedclock */
218 	sched_cookie = sparc_softintr_establish(IPL_SCHED, schedintr, NULL);
219 	if (sched_cookie == NULL)
220 		panic("timerattach: cannot establish schedintr");
221 
222 	cntr.cntreg = cntreg;
223 	cntr.limit >>= cntr.shift;
224 
225 	tc_init(&counter_timecounter);
226 }
227 
228 /*
229  * Both sun4 and sun4m can attach a timer on obio.
230  * The sun4m OPENPROM calls the timer the "counter".
231  * The sun4 timer must be probed.
232  */
233 static int
234 timermatch_obio(struct device *parent, struct cfdata *cf, void *aux)
235 {
236 #if defined(SUN4) || defined(SUN4M)
237 	union obio_attach_args *uoba = aux;
238 #endif
239 #if defined(SUN4)
240 	struct obio4_attach_args *oba;
241 #endif
242 
243 #if defined(SUN4M)
244 	if (uoba->uoba_isobio4 == 0)
245 		return (strcmp("counter", uoba->uoba_sbus.sa_name) == 0);
246 #endif /* SUN4M */
247 
248 	if (CPU_ISSUN4 == 0) {
249 		printf("timermatch_obio: attach args mixed up\n");
250 		return (0);
251 	}
252 
253 #if defined(SUN4)
254 	/* Only these sun4s have "timer" (others have "oclock") */
255 	if (cpuinfo.cpu_type != CPUTYP_4_300 &&
256 	    cpuinfo.cpu_type != CPUTYP_4_400)
257 		return (0);
258 
259 	/* Make sure there is something there */
260 	oba = &uoba->uoba_oba4;
261 	return (bus_space_probe(oba->oba_bustag, oba->oba_paddr,
262 				4,	/* probe size */
263 				0,	/* offset */
264 				0,	/* flags */
265 				NULL, NULL));
266 #endif /* SUN4 */
267 	panic("timermatch_obio: impossible");
268 }
269 
270 static void
271 timerattach_obio(struct device *parent, struct device *self, void *aux)
272 {
273 	union obio_attach_args *uoba = aux;
274 
275 	if (uoba->uoba_isobio4 == 0) {
276 #if defined(SUN4M)
277 		/* sun4m timer at obio */
278 		timerattach_obio_4m(parent, self, aux);
279 #endif /* SUN4M */
280 		return;
281 	}
282 
283 	if (uoba->uoba_isobio4 != 0) {
284 #if defined(SUN4)
285 		/* sun4 timer at obio */
286 		timerattach_obio_4(parent, self, aux);
287 #endif /* SUN4 */
288 	}
289 }
290 
291 CFATTACH_DECL(timer_obio, sizeof(struct device),
292     timermatch_obio, timerattach_obio, NULL, NULL);
293 
294 /*
295  * Only sun4c attaches a timer at mainbus
296  */
297 static int
298 timermatch_mainbus(struct device *parent, struct cfdata *cf, void *aux)
299 {
300 #if defined(SUN4C)
301 	struct mainbus_attach_args *ma = aux;
302 
303 	return (strcmp("counter-timer", ma->ma_name) == 0);
304 #else
305 	return (0);
306 #endif
307 }
308 
309 static void
310 timerattach_mainbus(struct device *parent, struct device *self, void *aux)
311 {
312 
313 #if defined(SUN4C)
314 	timerattach_mainbus_4c(parent, self, aux);
315 #endif /* SUN4C */
316 }
317 
318 CFATTACH_DECL(timer_mainbus, sizeof(struct device),
319     timermatch_mainbus, timerattach_mainbus, NULL, NULL);
320