2 * Copyright (c) 2005 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@backplane.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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
15 * the documentation and/or other materials provided with the
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * $DragonFly: src/sys/kern/kern_cputimer.c,v 1.5 2008/06/05 18:06:32 swildner Exp $
37 * Generic cputimer - access to a reliable, free-running counter.
40 #include <sys/param.h>
41 #include <sys/kernel.h>
42 #include <sys/systm.h>
43 #include <sys/thread.h>
44 #include <sys/globaldata.h>
45 #include <sys/systimer.h>
46 #include <sys/sysctl.h>
47 #include <sys/thread2.h>
49 static sysclock_t dummy_cputimer_count(void);
51 static struct cputimer dummy_cputimer = {
52 SLIST_ENTRY_INITIALIZER,
57 cputimer_default_fromhz,
58 cputimer_default_fromus,
59 cputimer_default_construct,
60 cputimer_default_destruct,
62 (1000000LL << 32) / 1000000,
63 (1000000000LL << 32) / 1000000,
67 struct cputimer *sys_cputimer = &dummy_cputimer;
68 SLIST_HEAD(, cputimer) cputimerhead = SLIST_HEAD_INITIALIZER(&cputimerhead);
71 * Generic cputimer API
74 cputimer_select(struct cputimer *timer, int pri)
79 * Calculate helper fields
81 cputimer_set_frequency(timer, timer->freq);
84 * Install a new cputimer if its priority allows it. If timer is
85 * passed as NULL we deinstall the current timer and revert to our
90 if (timer == NULL || pri >= sys_cputimer->pri) {
91 oldclock = sys_cputimer->count();
92 sys_cputimer->destruct(sys_cputimer);
93 sys_cputimer = &dummy_cputimer;
96 timer->construct(timer, oldclock);
97 cputimer_intr_config(timer);
103 * Register a timer. If the timer has already been registered, do nothing.
106 cputimer_register(struct cputimer *timer)
108 struct cputimer *scan;
111 * Initialize dummy_cputimer if the slist is empty, it does not get
112 * registered the normal way.
114 if (SLIST_EMPTY(&cputimerhead))
115 SLIST_FIRST(&cputimerhead) = &dummy_cputimer;
116 SLIST_FOREACH(scan, &cputimerhead, next) {
120 SLIST_INSERT_HEAD(&cputimerhead, timer, next);
124 * Deregister a timer. If the timer has already been deregistered, do nothing.
127 cputimer_deregister(struct cputimer *timer)
129 struct cputimer *scan;
130 struct cputimer *best;
133 * Locate and remove the timer. If the timer is our currently active
134 * timer, revert to the dummy timer.
136 SLIST_FOREACH(scan, &cputimerhead, next) {
138 if (timer == sys_cputimer)
139 cputimer_select(&dummy_cputimer, 0x7FFFFFFF);
140 SLIST_REMOVE(&cputimerhead, timer, cputimer, next);
146 * If sys_cputimer reverted to the dummy, select the best one
148 if (sys_cputimer == &dummy_cputimer) {
150 SLIST_FOREACH(scan, &cputimerhead, next) {
151 if (best == NULL || scan->pri > best->pri)
155 cputimer_select(best, 0x7FFFFFFF);
160 * Calculate usec / tick and nsec / tick, scaled by (1 << 32).
162 * so e.g. a 3 mhz timer would be 3 usec / tick x (1 << 32),
163 * or 3000 nsec / tick x (1 << 32)
166 cputimer_set_frequency(struct cputimer *timer, int freq)
169 timer->freq64_usec = (1000000LL << 32) / freq;
170 timer->freq64_nsec = (1000000000LL << 32) / freq;
171 if (timer == sys_cputimer)
172 cputimer_intr_config(timer);
176 cputimer_default_fromhz(int freq)
178 return(sys_cputimer->freq / freq + 1);
182 cputimer_default_fromus(int us)
184 return((int64_t)sys_cputimer->freq * us / 1000000);
188 * Dummy counter implementation
192 dummy_cputimer_count(void)
194 return(++dummy_cputimer.base);
198 cputimer_default_construct(struct cputimer *cputimer, sysclock_t oldclock)
200 cputimer->base = oldclock;
204 cputimer_default_destruct(struct cputimer *cputimer)
208 /************************************************************************
210 ************************************************************************
212 * Note: the ability to change the systimer is not currently enabled
213 * because it will mess up systimer calculations. You have to live
214 * with what is configured at boot.
217 sysctl_cputimer_reglist(SYSCTL_HANDLER_ARGS)
219 struct cputimer *scan;
224 * Build a list of available timers
226 SLIST_FOREACH(scan, &cputimerhead, next) {
227 if (error == 0 && loop)
228 error = SYSCTL_OUT(req, " ", 1);
230 error = SYSCTL_OUT(req, scan->name, strlen(scan->name));
237 sysctl_cputimer_name(SYSCTL_HANDLER_ARGS)
241 error = SYSCTL_OUT(req, sys_cputimer->name, strlen(sys_cputimer->name));
246 sysctl_cputimer_clock(SYSCTL_HANDLER_ARGS)
251 clock = sys_cputimer->count();
252 error = SYSCTL_OUT(req, &clock, sizeof(clock));
257 sysctl_cputimer_freq(SYSCTL_HANDLER_ARGS)
261 error = SYSCTL_OUT(req, &sys_cputimer->freq, sizeof(sys_cputimer->freq));
265 SYSCTL_DECL(_kern_cputimer);
266 SYSCTL_NODE(_kern, OID_AUTO, cputimer, CTLFLAG_RW, NULL, "cputimer");
268 SYSCTL_PROC(_kern_cputimer, OID_AUTO, select, CTLTYPE_STRING|CTLFLAG_RD,
269 NULL, 0, sysctl_cputimer_reglist, "A", "");
270 SYSCTL_PROC(_kern_cputimer, OID_AUTO, name, CTLTYPE_STRING|CTLFLAG_RD,
271 NULL, 0, sysctl_cputimer_name, "A", "");
272 SYSCTL_PROC(_kern_cputimer, OID_AUTO, clock, CTLTYPE_UINT|CTLFLAG_RD,
273 NULL, 0, sysctl_cputimer_clock, "IU", "");
274 SYSCTL_PROC(_kern_cputimer, OID_AUTO, freq, CTLTYPE_INT|CTLFLAG_RD,
275 NULL, 0, sysctl_cputimer_freq, "I", "");
277 static struct cputimer_intr *sys_cputimer_intr;
278 static uint32_t cputimer_intr_caps;
279 SLIST_HEAD(, cputimer_intr) cputimer_intr_head =
280 SLIST_HEAD_INITIALIZER(&cputimer_intr_head);
283 cputimer_intr_register(struct cputimer_intr *cti)
285 struct cputimer_intr *scan;
287 SLIST_FOREACH(scan, &cputimer_intr_head, next) {
291 cti->config(cti, sys_cputimer);
292 SLIST_INSERT_HEAD(&cputimer_intr_head, cti, next);
296 cputimer_intr_deregister(struct cputimer_intr *cti)
298 KKASSERT(cti != sys_cputimer_intr);
299 SLIST_REMOVE(&cputimer_intr_head, cti, cputimer_intr, next);
303 cputimer_intr_select(struct cputimer_intr *cti, int prio)
305 KKASSERT(cti != NULL);
310 if (sys_cputimer_intr == NULL) {
311 KKASSERT(cputimer_intr_caps == 0);
312 sys_cputimer_intr = cti;
316 if ((cti->caps & cputimer_intr_caps) == cputimer_intr_caps) {
317 if (prio > sys_cputimer_intr->prio) {
318 sys_cputimer_intr = cti;
329 cputimer_intr_default_enable(struct cputimer_intr *cti __unused)
334 cputimer_intr_default_restart(struct cputimer_intr *cti)
340 cputimer_intr_default_config(struct cputimer_intr *cti __unused,
341 const struct cputimer *timer __unused)
346 cputimer_intr_default_pmfixup(struct cputimer_intr *cti __unused)
351 cputimer_intr_default_initclock(struct cputimer_intr *cti __unused,
352 boolean_t selected __unused)
357 cputimer_intr_enable(void)
359 struct cputimer_intr *cti;
361 SLIST_FOREACH(cti, &cputimer_intr_head, next)
366 cputimer_intr_config(const struct cputimer *timer)
368 struct cputimer_intr *cti;
370 SLIST_FOREACH(cti, &cputimer_intr_head, next)
371 cti->config(cti, timer);
375 cputimer_intr_pmfixup(void)
377 struct cputimer_intr *cti;
379 SLIST_FOREACH(cti, &cputimer_intr_head, next)
384 cputimer_intr_reload(sysclock_t reload)
386 struct cputimer_intr *cti = sys_cputimer_intr;
388 cti->reload(cti, reload);
392 cputimer_intr_restart(void)
394 struct cputimer_intr *cti = sys_cputimer_intr;
400 cputimer_intr_select_caps(uint32_t caps)
402 struct cputimer_intr *cti, *maybe;
406 SLIST_FOREACH(cti, &cputimer_intr_head, next) {
407 if ((cti->caps & caps) == caps) {
410 else if (cti->prio > maybe->prio)
417 cputimer_intr_caps = caps;
418 error = cputimer_intr_select(maybe, CPUTIMER_INTR_PRIO_MAX);
425 cputimer_intr_initclocks(void)
427 struct cputimer_intr *cti, *ncti;
430 * An interrupt cputimer may deregister itself,
431 * so use SLIST_FOREACH_MUTABLE here.
433 SLIST_FOREACH_MUTABLE(cti, &cputimer_intr_head, next, ncti) {
434 boolean_t selected = FALSE;
436 if (cti == sys_cputimer_intr)
438 cti->initclock(cti, selected);
441 /* NOTE: Must be SECOND to allow platform initialization to go first */
442 SYSINIT(cputimer_intr, SI_BOOT2_CLOCKREG, SI_ORDER_SECOND,
443 cputimer_intr_initclocks, NULL)
446 sysctl_cputimer_intr_reglist(SYSCTL_HANDLER_ARGS)
448 struct cputimer_intr *scan;
453 * Build a list of available interrupt cputimers
455 SLIST_FOREACH(scan, &cputimer_intr_head, next) {
456 if (error == 0 && loop)
457 error = SYSCTL_OUT(req, " ", 1);
459 error = SYSCTL_OUT(req, scan->name, strlen(scan->name));
466 sysctl_cputimer_intr_freq(SYSCTL_HANDLER_ARGS)
470 error = SYSCTL_OUT(req, &sys_cputimer_intr->freq,
471 sizeof(sys_cputimer_intr->freq));
476 sysctl_cputimer_intr_select(SYSCTL_HANDLER_ARGS)
478 struct cputimer_intr *cti;
482 ksnprintf(name, sizeof(name), "%s", sys_cputimer_intr->name);
483 error = sysctl_handle_string(oidp, name, sizeof(name), req);
484 if (error != 0 || req->newptr == NULL)
487 SLIST_FOREACH(cti, &cputimer_intr_head, next) {
488 if (strcmp(cti->name, name) == 0)
493 if (cti == sys_cputimer_intr)
496 error = cputimer_intr_select(cti, CPUTIMER_INTR_PRIO_MAX);
498 cputimer_intr_restart();
502 SYSCTL_NODE(_kern_cputimer, OID_AUTO, intr, CTLFLAG_RW, NULL,
503 "interrupt cputimer");
505 SYSCTL_PROC(_kern_cputimer_intr, OID_AUTO, reglist, CTLTYPE_STRING|CTLFLAG_RD,
506 NULL, 0, sysctl_cputimer_intr_reglist, "A", "");
507 SYSCTL_PROC(_kern_cputimer_intr, OID_AUTO, freq, CTLTYPE_INT|CTLFLAG_RD,
508 NULL, 0, sysctl_cputimer_intr_freq, "I", "");
509 SYSCTL_PROC(_kern_cputimer_intr, OID_AUTO, select, CTLTYPE_STRING|CTLFLAG_RW,
510 NULL, 0, sysctl_cputimer_intr_select, "A", "");