1/*-
2 * Copyright (c) 2004-2007 Nate Lawson (SDG)
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/kern/kern_cpu.c 232793 2012-03-10 18:56:16Z mav $");
29
30#include <sys/param.h>
31#include <sys/bus.h>
32#include <sys/cpu.h>
33#include <sys/eventhandler.h>
34#include <sys/kernel.h>
35#include <sys/lock.h>
36#include <sys/malloc.h>
37#include <sys/module.h>
38#include <sys/proc.h>
39#include <sys/queue.h>
40#include <sys/sbuf.h>
41#include <sys/sched.h>
42#include <sys/smp.h>
43#include <sys/sysctl.h>
44#include <sys/systm.h>
45#include <sys/sx.h>
46#include <sys/timetc.h>
47#include <sys/taskqueue.h>
48
49#include "cpufreq_if.h"
50
51/*
52 * Common CPU frequency glue code. Drivers for specific hardware can
53 * attach this interface to allow users to get/set the CPU frequency.
54 */
55
56/*
57 * Number of levels we can handle. Levels are synthesized from settings
58 * so for M settings and N drivers, there may be M*N levels.
59 */
60#define CF_MAX_LEVELS 64
61
62struct cf_saved_freq {
63 struct cf_level level;
64 int priority;
65 SLIST_ENTRY(cf_saved_freq) link;
66};
67
68struct cpufreq_softc {
69 struct sx lock;
70 struct cf_level curr_level;
71 int curr_priority;
72 SLIST_HEAD(, cf_saved_freq) saved_freq;
73 struct cf_level_lst all_levels;
74 int all_count;
75 int max_mhz;
76 device_t dev;
77 struct sysctl_ctx_list sysctl_ctx;
78 struct task startup_task;
79 struct cf_level *levels_buf;
80};
81
82struct cf_setting_array {
83 struct cf_setting sets[MAX_SETTINGS];
84 int count;
85 TAILQ_ENTRY(cf_setting_array) link;
86};
87
88TAILQ_HEAD(cf_setting_lst, cf_setting_array);
89
90#define CF_MTX_INIT(x) sx_init((x), "cpufreq lock")
91#define CF_MTX_LOCK(x) sx_xlock((x))
92#define CF_MTX_UNLOCK(x) sx_xunlock((x))
93#define CF_MTX_ASSERT(x) sx_assert((x), SX_XLOCKED)
94
95#define CF_DEBUG(msg...) do { \
96 if (cf_verbose) \
97 printf("cpufreq: " msg); \
98 } while (0)
99
100static int cpufreq_attach(device_t dev);
101static void cpufreq_startup_task(void *ctx, int pending);
102static int cpufreq_detach(device_t dev);
103static int cf_set_method(device_t dev, const struct cf_level *level,
104 int priority);
105static int cf_get_method(device_t dev, struct cf_level *level);
106static int cf_levels_method(device_t dev, struct cf_level *levels,
107 int *count);
108static int cpufreq_insert_abs(struct cpufreq_softc *sc,
109 struct cf_setting *sets, int count);
110static int cpufreq_expand_set(struct cpufreq_softc *sc,
111 struct cf_setting_array *set_arr);
112static struct cf_level *cpufreq_dup_set(struct cpufreq_softc *sc,
113 struct cf_level *dup, struct cf_setting *set);
114static int cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS);
115static int cpufreq_levels_sysctl(SYSCTL_HANDLER_ARGS);
116static int cpufreq_settings_sysctl(SYSCTL_HANDLER_ARGS);
117
118static device_method_t cpufreq_methods[] = {
119 DEVMETHOD(device_probe, bus_generic_probe),
120 DEVMETHOD(device_attach, cpufreq_attach),
121 DEVMETHOD(device_detach, cpufreq_detach),
122
123 DEVMETHOD(cpufreq_set, cf_set_method),
124 DEVMETHOD(cpufreq_get, cf_get_method),
125 DEVMETHOD(cpufreq_levels, cf_levels_method),
126 {0, 0}
127};
128static driver_t cpufreq_driver = {
129 "cpufreq", cpufreq_methods, sizeof(struct cpufreq_softc)
130};
131static devclass_t cpufreq_dc;
132DRIVER_MODULE(cpufreq, cpu, cpufreq_driver, cpufreq_dc, 0, 0);
133
134static int cf_lowest_freq;
135static int cf_verbose;
136TUNABLE_INT("debug.cpufreq.lowest", &cf_lowest_freq);
137TUNABLE_INT("debug.cpufreq.verbose", &cf_verbose);
138static SYSCTL_NODE(_debug, OID_AUTO, cpufreq, CTLFLAG_RD, NULL,
139 "cpufreq debugging");
140SYSCTL_INT(_debug_cpufreq, OID_AUTO, lowest, CTLFLAG_RW, &cf_lowest_freq, 1,
141 "Don't provide levels below this frequency.");
142SYSCTL_INT(_debug_cpufreq, OID_AUTO, verbose, CTLFLAG_RW, &cf_verbose, 1,
143 "Print verbose debugging messages");
144
145static int
146cpufreq_attach(device_t dev)
147{
148 struct cpufreq_softc *sc;
149 struct pcpu *pc;
150 device_t parent;
151 uint64_t rate;
152 int numdevs;
153
154 CF_DEBUG("initializing %s\n", device_get_nameunit(dev));
155 sc = device_get_softc(dev);
156 parent = device_get_parent(dev);
157 sc->dev = dev;
158 sysctl_ctx_init(&sc->sysctl_ctx);
159 TAILQ_INIT(&sc->all_levels);
160 CF_MTX_INIT(&sc->lock);
161 sc->curr_level.total_set.freq = CPUFREQ_VAL_UNKNOWN;
162 SLIST_INIT(&sc->saved_freq);
163 /* Try to get nominal CPU freq to use it as maximum later if needed */
164 sc->max_mhz = cpu_get_nominal_mhz(dev);
165 /* If that fails, try to measure the current rate */
166 if (sc->max_mhz <= 0) {
167 pc = cpu_get_pcpu(dev);
168 if (cpu_est_clockrate(pc->pc_cpuid, &rate) == 0)
169 sc->max_mhz = rate / 1000000;
170 else
171 sc->max_mhz = CPUFREQ_VAL_UNKNOWN;
172 }
173
174 /*
175 * Only initialize one set of sysctls for all CPUs. In the future,
176 * if multiple CPUs can have different settings, we can move these
177 * sysctls to be under every CPU instead of just the first one.
178 */
179 numdevs = devclass_get_count(cpufreq_dc);
180 if (numdevs > 1)
181 return (0);
182
183 CF_DEBUG("initializing one-time data for %s\n",
184 device_get_nameunit(dev));
185 sc->levels_buf = malloc(CF_MAX_LEVELS * sizeof(*sc->levels_buf),
186 M_DEVBUF, M_WAITOK);
187 SYSCTL_ADD_PROC(&sc->sysctl_ctx,
188 SYSCTL_CHILDREN(device_get_sysctl_tree(parent)),
189 OID_AUTO, "freq", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
190 cpufreq_curr_sysctl, "I", "Current CPU frequency");
191 SYSCTL_ADD_PROC(&sc->sysctl_ctx,
192 SYSCTL_CHILDREN(device_get_sysctl_tree(parent)),
193 OID_AUTO, "freq_levels", CTLTYPE_STRING | CTLFLAG_RD, sc, 0,
194 cpufreq_levels_sysctl, "A", "CPU frequency levels");
195
196 /*
197 * Queue a one-shot broadcast that levels have changed.
198 * It will run once the system has completed booting.
199 */
200 TASK_INIT(&sc->startup_task, 0, cpufreq_startup_task, dev);
201 taskqueue_enqueue(taskqueue_thread, &sc->startup_task);
202
203 return (0);
204}
205
206/* Handle any work to be done for all drivers that attached during boot. */
207static void
208cpufreq_startup_task(void *ctx, int pending)
209{
210
211 cpufreq_settings_changed((device_t)ctx);
212}
213
214static int
215cpufreq_detach(device_t dev)
216{
217 struct cpufreq_softc *sc;
218 struct cf_saved_freq *saved_freq;
219 int numdevs;
220
221 CF_DEBUG("shutdown %s\n", device_get_nameunit(dev));
222 sc = device_get_softc(dev);
223 sysctl_ctx_free(&sc->sysctl_ctx);
224
225 while ((saved_freq = SLIST_FIRST(&sc->saved_freq)) != NULL) {
226 SLIST_REMOVE_HEAD(&sc->saved_freq, link);
227 free(saved_freq, M_TEMP);
228 }
229
230 /* Only clean up these resources when the last device is detaching. */
231 numdevs = devclass_get_count(cpufreq_dc);
232 if (numdevs == 1) {
233 CF_DEBUG("final shutdown for %s\n", device_get_nameunit(dev));
234 free(sc->levels_buf, M_DEVBUF);
235 }
236
237 return (0);
238}
239
240static int
241cf_set_method(device_t dev, const struct cf_level *level, int priority)
242{
243 struct cpufreq_softc *sc;
244 const struct cf_setting *set;
245 struct cf_saved_freq *saved_freq, *curr_freq;
246 struct pcpu *pc;
247 int error, i;
248
249 sc = device_get_softc(dev);
250 error = 0;
251 set = NULL;
252 saved_freq = NULL;
253
254 /* We are going to change levels so notify the pre-change handler. */
255 EVENTHANDLER_INVOKE(cpufreq_pre_change, level, &error);
256 if (error != 0) {
257 EVENTHANDLER_INVOKE(cpufreq_post_change, level, error);
258 return (error);
259 }
260
261 CF_MTX_LOCK(&sc->lock);
262
263#ifdef SMP
264 /*
265 * If still booting and secondary CPUs not started yet, don't allow
266 * changing the frequency until they're online. This is because we
267 * can't switch to them using sched_bind() and thus we'd only be
268 * switching the main CPU. XXXTODO: Need to think more about how to
269 * handle having different CPUs at different frequencies.
270 */
271 if (mp_ncpus > 1 && !smp_active) {
272 device_printf(dev, "rejecting change, SMP not started yet\n");
273 error = ENXIO;
274 goto out;
275 }
276#endif /* SMP */
277
278 /*
279 * If the requested level has a lower priority, don't allow
280 * the new level right now.
281 */
282 if (priority < sc->curr_priority) {
283 CF_DEBUG("ignoring, curr prio %d less than %d\n", priority,
284 sc->curr_priority);
285 error = EPERM;
286 goto out;
287 }
288
289 /*
290 * If the caller didn't specify a level and one is saved, prepare to
291 * restore the saved level. If none has been saved, return an error.
292 */
293 if (level == NULL) {
294 saved_freq = SLIST_FIRST(&sc->saved_freq);
295 if (saved_freq == NULL) {
296 CF_DEBUG("NULL level, no saved level\n");
297 error = ENXIO;
298 goto out;
299 }
300 level = &saved_freq->level;
301 priority = saved_freq->priority;
302 CF_DEBUG("restoring saved level, freq %d prio %d\n",
303 level->total_set.freq, priority);
304 }
305
306 /* Reject levels that are below our specified threshold. */
307 if (level->total_set.freq < cf_lowest_freq) {
308 CF_DEBUG("rejecting freq %d, less than %d limit\n",
309 level->total_set.freq, cf_lowest_freq);
310 error = EINVAL;
311 goto out;
312 }
313
314 /* If already at this level, just return. */
315 if (sc->curr_level.total_set.freq == level->total_set.freq) {
316 CF_DEBUG("skipping freq %d, same as current level %d\n",
317 level->total_set.freq, sc->curr_level.total_set.freq);
318 goto skip;
319 }
320
321 /* First, set the absolute frequency via its driver. */
322 set = &level->abs_set;
323 if (set->dev) {
324 if (!device_is_attached(set->dev)) {
325 error = ENXIO;
326 goto out;
327 }
328
329 /* Bind to the target CPU before switching. */
330 pc = cpu_get_pcpu(set->dev);
331 thread_lock(curthread);
332 sched_bind(curthread, pc->pc_cpuid);
333 thread_unlock(curthread);
334 CF_DEBUG("setting abs freq %d on %s (cpu %d)\n", set->freq,
335 device_get_nameunit(set->dev), PCPU_GET(cpuid));
336 error = CPUFREQ_DRV_SET(set->dev, set);
337 thread_lock(curthread);
338 sched_unbind(curthread);
339 thread_unlock(curthread);
340 if (error) {
341 goto out;
342 }
343 }
344
345 /* Next, set any/all relative frequencies via their drivers. */
346 for (i = 0; i < level->rel_count; i++) {
347 set = &level->rel_set[i];
348 if (!device_is_attached(set->dev)) {
349 error = ENXIO;
350 goto out;
351 }
352
353 /* Bind to the target CPU before switching. */
354 pc = cpu_get_pcpu(set->dev);
355 thread_lock(curthread);
356 sched_bind(curthread, pc->pc_cpuid);
357 thread_unlock(curthread);
358 CF_DEBUG("setting rel freq %d on %s (cpu %d)\n", set->freq,
359 device_get_nameunit(set->dev), PCPU_GET(cpuid));
360 error = CPUFREQ_DRV_SET(set->dev, set);
361 thread_lock(curthread);
362 sched_unbind(curthread);
363 thread_unlock(curthread);
364 if (error) {
365 /* XXX Back out any successful setting? */
366 goto out;
367 }
368 }
369
370skip:
371 /*
372 * Before recording the current level, check if we're going to a
373 * higher priority. If so, save the previous level and priority.
374 */
375 if (sc->curr_level.total_set.freq != CPUFREQ_VAL_UNKNOWN &&
376 priority > sc->curr_priority) {
377 CF_DEBUG("saving level, freq %d prio %d\n",
378 sc->curr_level.total_set.freq, sc->curr_priority);
379 curr_freq = malloc(sizeof(*curr_freq), M_TEMP, M_NOWAIT);
380 if (curr_freq == NULL) {
381 error = ENOMEM;
382 goto out;
383 }
384 curr_freq->level = sc->curr_level;
385 curr_freq->priority = sc->curr_priority;
386 SLIST_INSERT_HEAD(&sc->saved_freq, curr_freq, link);
387 }
388 sc->curr_level = *level;
389 sc->curr_priority = priority;
390
391 /* If we were restoring a saved state, reset it to "unused". */
392 if (saved_freq != NULL) {
393 CF_DEBUG("resetting saved level\n");
394 sc->curr_level.total_set.freq = CPUFREQ_VAL_UNKNOWN;
395 SLIST_REMOVE_HEAD(&sc->saved_freq, link);
396 free(saved_freq, M_TEMP);
397 }
398
399out:
400 CF_MTX_UNLOCK(&sc->lock);
401
402 /*
403 * We changed levels (or attempted to) so notify the post-change
404 * handler of new frequency or error.
405 */
406 EVENTHANDLER_INVOKE(cpufreq_post_change, level, error);
407 if (error && set)
408 device_printf(set->dev, "set freq failed, err %d\n", error);
409
410 return (error);
411}
412
413static int
414cf_get_method(device_t dev, struct cf_level *level)
415{
416 struct cpufreq_softc *sc;
417 struct cf_level *levels;
418 struct cf_setting *curr_set, set;
419 struct pcpu *pc;
420 device_t *devs;
421 int count, error, i, n, numdevs;
422 uint64_t rate;
423
424 sc = device_get_softc(dev);
425 error = 0;
426 levels = NULL;
427
428 /* If we already know the current frequency, we're done. */
429 CF_MTX_LOCK(&sc->lock);
430 curr_set = &sc->curr_level.total_set;
431 if (curr_set->freq != CPUFREQ_VAL_UNKNOWN) {
432 CF_DEBUG("get returning known freq %d\n", curr_set->freq);
433 goto out;
434 }
435 CF_MTX_UNLOCK(&sc->lock);
436
437 /*
438 * We need to figure out the current level. Loop through every
439 * driver, getting the current setting. Then, attempt to get a best
440 * match of settings against each level.
441 */
442 count = CF_MAX_LEVELS;
443 levels = malloc(count * sizeof(*levels), M_TEMP, M_NOWAIT);
444 if (levels == NULL)
445 return (ENOMEM);
446 error = CPUFREQ_LEVELS(sc->dev, levels, &count);
447 if (error) {
448 if (error == E2BIG)
449 printf("cpufreq: need to increase CF_MAX_LEVELS\n");
450 free(levels, M_TEMP);
451 return (error);
452 }
453 error = device_get_children(device_get_parent(dev), &devs, &numdevs);
454 if (error) {
455 free(levels, M_TEMP);
456 return (error);
457 }
458
459 /*
460 * Reacquire the lock and search for the given level.
461 *
462 * XXX Note: this is not quite right since we really need to go
463 * through each level and compare both absolute and relative
464 * settings for each driver in the system before making a match.
465 * The estimation code below catches this case though.
466 */
467 CF_MTX_LOCK(&sc->lock);
468 for (n = 0; n < numdevs && curr_set->freq == CPUFREQ_VAL_UNKNOWN; n++) {
469 if (!device_is_attached(devs[n]))
470 continue;
471 if (CPUFREQ_DRV_GET(devs[n], &set) != 0)
472 continue;
473 for (i = 0; i < count; i++) {
474 if (set.freq == levels[i].total_set.freq) {
475 sc->curr_level = levels[i];
476 break;
477 }
478 }
479 }
480 free(devs, M_TEMP);
481 if (curr_set->freq != CPUFREQ_VAL_UNKNOWN) {
482 CF_DEBUG("get matched freq %d from drivers\n", curr_set->freq);
483 goto out;
484 }
485
486 /*
487 * We couldn't find an exact match, so attempt to estimate and then
488 * match against a level.
489 */
490 pc = cpu_get_pcpu(dev);
491 if (pc == NULL) {
492 error = ENXIO;
493 goto out;
494 }
495 cpu_est_clockrate(pc->pc_cpuid, &rate);
496 rate /= 1000000;
497 for (i = 0; i < count; i++) {
498 if (CPUFREQ_CMP(rate, levels[i].total_set.freq)) {
499 sc->curr_level = levels[i];
500 CF_DEBUG("get estimated freq %d\n", curr_set->freq);
501 goto out;
502 }
503 }
504 error = ENXIO;
505
506out:
507 if (error == 0)
508 *level = sc->curr_level;
509
510 CF_MTX_UNLOCK(&sc->lock);
511 if (levels)
512 free(levels, M_TEMP);
513 return (error);
514}
515
516static int
517cf_levels_method(device_t dev, struct cf_level *levels, int *count)
518{
519 struct cf_setting_array *set_arr;
520 struct cf_setting_lst rel_sets;
521 struct cpufreq_softc *sc;
522 struct cf_level *lev;
523 struct cf_setting *sets;
524 struct pcpu *pc;
525 device_t *devs;
526 int error, i, numdevs, set_count, type;
527 uint64_t rate;
528
529 if (levels == NULL || count == NULL)
530 return (EINVAL);
531
532 TAILQ_INIT(&rel_sets);
533 sc = device_get_softc(dev);
534 error = device_get_children(device_get_parent(dev), &devs, &numdevs);
535 if (error)
536 return (error);
537 sets = malloc(MAX_SETTINGS * sizeof(*sets), M_TEMP, M_NOWAIT);
538 if (sets == NULL) {
539 free(devs, M_TEMP);
540 return (ENOMEM);
541 }
542
543 /* Get settings from all cpufreq drivers. */
544 CF_MTX_LOCK(&sc->lock);
545 for (i = 0; i < numdevs; i++) {
546 /* Skip devices that aren't ready. */
547 if (!device_is_attached(devs[i]))
548 continue;
549
550 /*
551 * Get settings, skipping drivers that offer no settings or
552 * provide settings for informational purposes only.
553 */
554 error = CPUFREQ_DRV_TYPE(devs[i], &type);
555 if (error || (type & CPUFREQ_FLAG_INFO_ONLY)) {
556 if (error == 0) {
557 CF_DEBUG("skipping info-only driver %s\n",
558 device_get_nameunit(devs[i]));
559 }
560 continue;
561 }
562 set_count = MAX_SETTINGS;
563 error = CPUFREQ_DRV_SETTINGS(devs[i], sets, &set_count);
564 if (error || set_count == 0)
565 continue;
566
567 /* Add the settings to our absolute/relative lists. */
568 switch (type & CPUFREQ_TYPE_MASK) {
569 case CPUFREQ_TYPE_ABSOLUTE:
570 error = cpufreq_insert_abs(sc, sets, set_count);
571 break;
572 case CPUFREQ_TYPE_RELATIVE:
573 CF_DEBUG("adding %d relative settings\n", set_count);
574 set_arr = malloc(sizeof(*set_arr), M_TEMP, M_NOWAIT);
575 if (set_arr == NULL) {
576 error = ENOMEM;
577 goto out;
578 }
579 bcopy(sets, set_arr->sets, set_count * sizeof(*sets));
580 set_arr->count = set_count;
581 TAILQ_INSERT_TAIL(&rel_sets, set_arr, link);
582 break;
583 default:
584 error = EINVAL;
585 }
586 if (error)
587 goto out;
588 }
589
590 /*
591 * If there are no absolute levels, create a fake one at 100%. We
592 * then cache the clockrate for later use as our base frequency.
593 */
594 if (TAILQ_EMPTY(&sc->all_levels)) {
595 if (sc->max_mhz == CPUFREQ_VAL_UNKNOWN) {
596 sc->max_mhz = cpu_get_nominal_mhz(dev);
597 /*
598 * If the CPU can't report a rate for 100%, hope
599 * the CPU is running at its nominal rate right now,
600 * and use that instead.
601 */
602 if (sc->max_mhz <= 0) {
603 pc = cpu_get_pcpu(dev);
604 cpu_est_clockrate(pc->pc_cpuid, &rate);
605 sc->max_mhz = rate / 1000000;
606 }
607 }
608 memset(&sets[0], CPUFREQ_VAL_UNKNOWN, sizeof(*sets));
609 sets[0].freq = sc->max_mhz;
610 sets[0].dev = NULL;
611 error = cpufreq_insert_abs(sc, sets, 1);
612 if (error)
613 goto out;
614 }
615
616 /* Create a combined list of absolute + relative levels. */
617 TAILQ_FOREACH(set_arr, &rel_sets, link)
618 cpufreq_expand_set(sc, set_arr);
619
620 /* If the caller doesn't have enough space, return the actual count. */
621 if (sc->all_count > *count) {
622 *count = sc->all_count;
623 error = E2BIG;
624 goto out;
625 }
626
627 /* Finally, output the list of levels. */
628 i = 0;
629 TAILQ_FOREACH(lev, &sc->all_levels, link) {
630
631 /* Skip levels that have a frequency that is too low. */
632 if (lev->total_set.freq < cf_lowest_freq) {
633 sc->all_count--;
634 continue;
635 }
636
637 levels[i] = *lev;
638 i++;
639 }
640 *count = sc->all_count;
641 error = 0;
642
643out:
644 /* Clear all levels since we regenerate them each time. */
645 while ((lev = TAILQ_FIRST(&sc->all_levels)) != NULL) {
646 TAILQ_REMOVE(&sc->all_levels, lev, link);
647 free(lev, M_TEMP);
648 }
649 sc->all_count = 0;
650
651 CF_MTX_UNLOCK(&sc->lock);
652 while ((set_arr = TAILQ_FIRST(&rel_sets)) != NULL) {
653 TAILQ_REMOVE(&rel_sets, set_arr, link);
654 free(set_arr, M_TEMP);
655 }
656 free(devs, M_TEMP);
657 free(sets, M_TEMP);
658 return (error);
659}
660
661/*
662 * Create levels for an array of absolute settings and insert them in
663 * sorted order in the specified list.
664 */
665static int
666cpufreq_insert_abs(struct cpufreq_softc *sc, struct cf_setting *sets,
667 int count)
668{
669 struct cf_level_lst *list;
670 struct cf_level *level, *search;
671 int i;
672
673 CF_MTX_ASSERT(&sc->lock);
674
675 list = &sc->all_levels;
676 for (i = 0; i < count; i++) {
677 level = malloc(sizeof(*level), M_TEMP, M_NOWAIT | M_ZERO);
678 if (level == NULL)
679 return (ENOMEM);
680 level->abs_set = sets[i];
681 level->total_set = sets[i];
682 level->total_set.dev = NULL;
683 sc->all_count++;
684
685 if (TAILQ_EMPTY(list)) {
686 CF_DEBUG("adding abs setting %d at head\n",
687 sets[i].freq);
688 TAILQ_INSERT_HEAD(list, level, link);
689 continue;
690 }
691
692 TAILQ_FOREACH_REVERSE(search, list, cf_level_lst, link) {
693 if (sets[i].freq <= search->total_set.freq) {
694 CF_DEBUG("adding abs setting %d after %d\n",
695 sets[i].freq, search->total_set.freq);
696 TAILQ_INSERT_AFTER(list, search, level, link);
697 break;
698 }
699 }
700 }
701 return (0);
702}
703
704/*
705 * Expand a group of relative settings, creating derived levels from them.
706 */
707static int
708cpufreq_expand_set(struct cpufreq_softc *sc, struct cf_setting_array *set_arr)
709{
710 struct cf_level *fill, *search;
711 struct cf_setting *set;
712 int i;
713
714 CF_MTX_ASSERT(&sc->lock);
715
716 /*
717 * Walk the set of all existing levels in reverse. This is so we
718 * create derived states from the lowest absolute settings first
719 * and discard duplicates created from higher absolute settings.
720 * For instance, a level of 50 Mhz derived from 100 Mhz + 50% is
721 * preferable to 200 Mhz + 25% because absolute settings are more
722 * efficient since they often change the voltage as well.
723 */
724 TAILQ_FOREACH_REVERSE(search, &sc->all_levels, cf_level_lst, link) {
725 /* Add each setting to the level, duplicating if necessary. */
726 for (i = 0; i < set_arr->count; i++) {
727 set = &set_arr->sets[i];
728
729 /*
730 * If this setting is less than 100%, split the level
731 * into two and add this setting to the new level.
732 */
733 fill = search;
734 if (set->freq < 10000) {
735 fill = cpufreq_dup_set(sc, search, set);
736
737 /*
738 * The new level was a duplicate of an existing
739 * level or its absolute setting is too high
740 * so we freed it. For example, we discard a
741 * derived level of 1000 MHz/25% if a level
742 * of 500 MHz/100% already exists.
743 */
744 if (fill == NULL)
745 break;
746 }
747
748 /* Add this setting to the existing or new level. */
749 KASSERT(fill->rel_count < MAX_SETTINGS,
750 ("cpufreq: too many relative drivers (%d)",
751 MAX_SETTINGS));
752 fill->rel_set[fill->rel_count] = *set;
753 fill->rel_count++;
754 CF_DEBUG(
755 "expand set added rel setting %d%% to %d level\n",
756 set->freq / 100, fill->total_set.freq);
757 }
758 }
759
760 return (0);
761}
762
763static struct cf_level *
764cpufreq_dup_set(struct cpufreq_softc *sc, struct cf_level *dup,
765 struct cf_setting *set)
766{
767 struct cf_level_lst *list;
768 struct cf_level *fill, *itr;
769 struct cf_setting *fill_set, *itr_set;
770 int i;
771
772 CF_MTX_ASSERT(&sc->lock);
773
774 /*
775 * Create a new level, copy it from the old one, and update the
776 * total frequency and power by the percentage specified in the
777 * relative setting.
778 */
779 fill = malloc(sizeof(*fill), M_TEMP, M_NOWAIT);
780 if (fill == NULL)
781 return (NULL);
782 *fill = *dup;
783 fill_set = &fill->total_set;
784 fill_set->freq =
785 ((uint64_t)fill_set->freq * set->freq) / 10000;
786 if (fill_set->power != CPUFREQ_VAL_UNKNOWN) {
787 fill_set->power = ((uint64_t)fill_set->power * set->freq)
788 / 10000;
789 }
790 if (set->lat != CPUFREQ_VAL_UNKNOWN) {
791 if (fill_set->lat != CPUFREQ_VAL_UNKNOWN)
792 fill_set->lat += set->lat;
793 else
794 fill_set->lat = set->lat;
795 }
796 CF_DEBUG("dup set considering derived setting %d\n", fill_set->freq);
797
798 /*
799 * If we copied an old level that we already modified (say, at 100%),
800 * we need to remove that setting before adding this one. Since we
801 * process each setting array in order, we know any settings for this
802 * driver will be found at the end.
803 */
804 for (i = fill->rel_count; i != 0; i--) {
805 if (fill->rel_set[i - 1].dev != set->dev)
806 break;
807 CF_DEBUG("removed last relative driver: %s\n",
808 device_get_nameunit(set->dev));
809 fill->rel_count--;
810 }
811
812 /*
813 * Insert the new level in sorted order. If it is a duplicate of an
814 * existing level (1) or has an absolute setting higher than the
815 * existing level (2), do not add it. We can do this since any such
816 * level is guaranteed use less power. For example (1), a level with
817 * one absolute setting of 800 Mhz uses less power than one composed
818 * of an absolute setting of 1600 Mhz and a relative setting at 50%.
819 * Also for example (2), a level of 800 Mhz/75% is preferable to
820 * 1600 Mhz/25% even though the latter has a lower total frequency.
821 */
822 list = &sc->all_levels;
823 KASSERT(!TAILQ_EMPTY(list), ("all levels list empty in dup set"));
824 TAILQ_FOREACH_REVERSE(itr, list, cf_level_lst, link) {
825 itr_set = &itr->total_set;
826 if (CPUFREQ_CMP(fill_set->freq, itr_set->freq)) {
827 CF_DEBUG("dup set rejecting %d (dupe)\n",
828 fill_set->freq);
829 itr = NULL;
830 break;
831 } else if (fill_set->freq < itr_set->freq) {
832 if (fill->abs_set.freq <= itr->abs_set.freq) {
833 CF_DEBUG(
834 "dup done, inserting new level %d after %d\n",
835 fill_set->freq, itr_set->freq);
836 TAILQ_INSERT_AFTER(list, itr, fill, link);
837 sc->all_count++;
838 } else {
839 CF_DEBUG("dup set rejecting %d (abs too big)\n",
840 fill_set->freq);
841 itr = NULL;
842 }
843 break;
844 }
845 }
846
847 /* We didn't find a good place for this new level so free it. */
848 if (itr == NULL) {
849 CF_DEBUG("dup set freeing new level %d (not optimal)\n",
850 fill_set->freq);
851 free(fill, M_TEMP);
852 fill = NULL;
853 }
854
855 return (fill);
856}
857
858static int
859cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS)
860{
861 struct cpufreq_softc *sc;
862 struct cf_level *levels;
863 int best, count, diff, bdiff, devcount, error, freq, i, n;
864 device_t *devs;
865
866 devs = NULL;
867 sc = oidp->oid_arg1;
868 levels = sc->levels_buf;
869
870 error = CPUFREQ_GET(sc->dev, &levels[0]);
871 if (error)
872 goto out;
873 freq = levels[0].total_set.freq;
874 error = sysctl_handle_int(oidp, &freq, 0, req);
875 if (error != 0 || req->newptr == NULL)
876 goto out;
877
878 /*
879 * While we only call cpufreq_get() on one device (assuming all
880 * CPUs have equal levels), we call cpufreq_set() on all CPUs.
881 * This is needed for some MP systems.
882 */
883 error = devclass_get_devices(cpufreq_dc, &devs, &devcount);
884 if (error)
885 goto out;
886 for (n = 0; n < devcount; n++) {
887 count = CF_MAX_LEVELS;
888 error = CPUFREQ_LEVELS(devs[n], levels, &count);
889 if (error) {
890 if (error == E2BIG)
891 printf(
892 "cpufreq: need to increase CF_MAX_LEVELS\n");
893 break;
894 }
895 best = 0;
896 bdiff = 1 << 30;
897 for (i = 0; i < count; i++) {
898 diff = abs(levels[i].total_set.freq - freq);
899 if (diff < bdiff) {
900 bdiff = diff;
901 best = i;
902 }
903 }
904 error = CPUFREQ_SET(devs[n], &levels[best], CPUFREQ_PRIO_USER);
905 }
906
907out:
908 if (devs)
909 free(devs, M_TEMP);
910 return (error);
911}
912
913static int
914cpufreq_levels_sysctl(SYSCTL_HANDLER_ARGS)
915{
916 struct cpufreq_softc *sc;
917 struct cf_level *levels;
918 struct cf_setting *set;
919 struct sbuf sb;
920 int count, error, i;
921
922 sc = oidp->oid_arg1;
923 sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND);
924
925 /* Get settings from the device and generate the output string. */
926 count = CF_MAX_LEVELS;
927 levels = sc->levels_buf;
928 if (levels == NULL) {
929 sbuf_delete(&sb);
930 return (ENOMEM);
931 }
932 error = CPUFREQ_LEVELS(sc->dev, levels, &count);
933 if (error) {
934 if (error == E2BIG)
935 printf("cpufreq: need to increase CF_MAX_LEVELS\n");
936 goto out;
937 }
938 if (count) {
939 for (i = 0; i < count; i++) {
940 set = &levels[i].total_set;
941 sbuf_printf(&sb, "%d/%d ", set->freq, set->power);
942 }
943 } else
944 sbuf_cpy(&sb, "0");
945 sbuf_trim(&sb);
946 sbuf_finish(&sb);
947 error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
948
949out:
950 sbuf_delete(&sb);
951 return (error);
952}
953
954static int
955cpufreq_settings_sysctl(SYSCTL_HANDLER_ARGS)
956{
957 device_t dev;
958 struct cf_setting *sets;
959 struct sbuf sb;
960 int error, i, set_count;
961
962 dev = oidp->oid_arg1;
963 sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND);
964
965 /* Get settings from the device and generate the output string. */
966 set_count = MAX_SETTINGS;
967 sets = malloc(set_count * sizeof(*sets), M_TEMP, M_NOWAIT);
968 if (sets == NULL) {
969 sbuf_delete(&sb);
970 return (ENOMEM);
971 }
972 error = CPUFREQ_DRV_SETTINGS(dev, sets, &set_count);
973 if (error)
974 goto out;
975 if (set_count) {
976 for (i = 0; i < set_count; i++)
977 sbuf_printf(&sb, "%d/%d ", sets[i].freq, sets[i].power);
978 } else
979 sbuf_cpy(&sb, "0");
980 sbuf_trim(&sb);
981 sbuf_finish(&sb);
982 error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
983
984out:
985 free(sets, M_TEMP);
986 sbuf_delete(&sb);
987 return (error);
988}
989
990int
991cpufreq_register(device_t dev)
992{
993 struct cpufreq_softc *sc;
994 device_t cf_dev, cpu_dev;
995
996 /* Add a sysctl to get each driver's settings separately. */
997 SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
998 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
999 OID_AUTO, "freq_settings", CTLTYPE_STRING | CTLFLAG_RD, dev, 0,
1000 cpufreq_settings_sysctl, "A", "CPU frequency driver settings");
1001
1002 /*
1003 * Add only one cpufreq device to each CPU. Currently, all CPUs
1004 * must offer the same levels and be switched at the same time.
1005 */
1006 cpu_dev = device_get_parent(dev);
1007 if ((cf_dev = device_find_child(cpu_dev, "cpufreq", -1))) {
1008 sc = device_get_softc(cf_dev);
1009 sc->max_mhz = CPUFREQ_VAL_UNKNOWN;
1010 return (0);
1011 }
1012
1013 /* Add the child device and possibly sysctls. */
1014 cf_dev = BUS_ADD_CHILD(cpu_dev, 0, "cpufreq", -1);
1015 if (cf_dev == NULL)
1016 return (ENOMEM);
1017 device_quiet(cf_dev);
1018
1019 return (device_probe_and_attach(cf_dev));
1020}
1021
1022int
1023cpufreq_unregister(device_t dev)
1024{
1025 device_t cf_dev, *devs;
1026 int cfcount, devcount, error, i, type;
1027
1028 /*
1029 * If this is the last cpufreq child device, remove the control
1030 * device as well. We identify cpufreq children by calling a method
1031 * they support.
1032 */
1033 error = device_get_children(device_get_parent(dev), &devs, &devcount);
1034 if (error)
1035 return (error);
1036 cf_dev = device_find_child(device_get_parent(dev), "cpufreq", -1);
1037 if (cf_dev == NULL) {
1038 device_printf(dev,
1039 "warning: cpufreq_unregister called with no cpufreq device active\n");
1040 return (0);
1041 }
1042 cfcount = 0;
1043 for (i = 0; i < devcount; i++) {
1044 if (!device_is_attached(devs[i]))
1045 continue;
1046 if (CPUFREQ_DRV_TYPE(devs[i], &type) == 0)
1047 cfcount++;
1048 }
1049 if (cfcount <= 1)
1050 device_delete_child(device_get_parent(cf_dev), cf_dev);
1051 free(devs, M_TEMP);
1052
1053 return (0);
1054}
1055
1056int
1057cpufreq_settings_changed(device_t dev)
1058{
1059
1060 EVENTHANDLER_INVOKE(cpufreq_levels_changed,
1061 device_get_unit(device_get_parent(dev)));
1062 return (0);
1063}