1/*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2004-2007 Nate Lawson (SDG) 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29#include <sys/param.h> 30#include <sys/bus.h> 31#include <sys/cpu.h> 32#include <sys/eventhandler.h> 33#include <sys/kernel.h> 34#include <sys/lock.h> 35#include <sys/malloc.h> 36#include <sys/module.h> 37#include <sys/proc.h> 38#include <sys/queue.h> 39#include <sys/sbuf.h> 40#include <sys/sched.h> 41#include <sys/smp.h> 42#include <sys/sysctl.h> 43#include <sys/systm.h> 44#include <sys/sx.h> 45#include <sys/timetc.h> 46#include <sys/taskqueue.h> 47 48#include "cpufreq_if.h" 49 50/* 51 * Common CPU frequency glue code. Drivers for specific hardware can 52 * attach this interface to allow users to get/set the CPU frequency. 53 */ 54 55/* 56 * Number of levels we can handle. Levels are synthesized from settings 57 * so for M settings and N drivers, there may be M*N levels. 58 */ 59#define CF_MAX_LEVELS 256 60 61struct cf_saved_freq { 62 struct cf_level level; 63 int priority; 64 SLIST_ENTRY(cf_saved_freq) link; 65}; 66 67struct cpufreq_softc { 68 struct sx lock; 69 struct cf_level curr_level; 70 int curr_priority; 71 SLIST_HEAD(, cf_saved_freq) saved_freq; 72 struct cf_level_lst all_levels; 73 int all_count; 74 int max_mhz; 75 device_t dev; 76 device_t cf_drv_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}; 128 129static driver_t cpufreq_driver = { 130 "cpufreq", cpufreq_methods, sizeof(struct cpufreq_softc) 131}; 132 133DRIVER_MODULE(cpufreq, cpu, cpufreq_driver, 0, 0); 134 135static int cf_lowest_freq; 136static int cf_verbose; 137static SYSCTL_NODE(_debug, OID_AUTO, cpufreq, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 138 "cpufreq debugging"); 139SYSCTL_INT(_debug_cpufreq, OID_AUTO, lowest, CTLFLAG_RWTUN, &cf_lowest_freq, 1, 140 "Don't provide levels below this frequency."); 141SYSCTL_INT(_debug_cpufreq, OID_AUTO, verbose, CTLFLAG_RWTUN, &cf_verbose, 1, 142 "Print verbose debugging messages"); 143 144/* 145 * This is called as the result of a hardware specific frequency control driver 146 * calling cpufreq_register. It provides a general interface for system wide 147 * frequency controls and operates on a per cpu basis. 148 */ 149static int 150cpufreq_attach(device_t dev) 151{ 152 struct cpufreq_softc *sc; 153 struct pcpu *pc; 154 device_t parent; 155 uint64_t rate; 156 157 CF_DEBUG("initializing %s\n", device_get_nameunit(dev)); 158 sc = device_get_softc(dev); 159 parent = device_get_parent(dev); 160 sc->dev = dev; 161 sysctl_ctx_init(&sc->sysctl_ctx); 162 TAILQ_INIT(&sc->all_levels); 163 CF_MTX_INIT(&sc->lock); 164 sc->curr_level.total_set.freq = CPUFREQ_VAL_UNKNOWN; 165 SLIST_INIT(&sc->saved_freq); 166 /* Try to get nominal CPU freq to use it as maximum later if needed */ 167 sc->max_mhz = cpu_get_nominal_mhz(dev); 168 /* If that fails, try to measure the current rate */ 169 if (sc->max_mhz <= 0) { 170 CF_DEBUG("Unable to obtain nominal frequency.\n"); 171 pc = cpu_get_pcpu(dev); 172 if (cpu_est_clockrate(pc->pc_cpuid, &rate) == 0) 173 sc->max_mhz = rate / 1000000; 174 else 175 sc->max_mhz = CPUFREQ_VAL_UNKNOWN; 176 } 177 178 CF_DEBUG("initializing one-time data for %s\n", 179 device_get_nameunit(dev)); 180 sc->levels_buf = malloc(CF_MAX_LEVELS * sizeof(*sc->levels_buf), 181 M_DEVBUF, M_WAITOK); 182 SYSCTL_ADD_PROC(&sc->sysctl_ctx, 183 SYSCTL_CHILDREN(device_get_sysctl_tree(parent)), 184 OID_AUTO, "freq", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 185 sc, 0, cpufreq_curr_sysctl, "I", "Current CPU frequency"); 186 SYSCTL_ADD_PROC(&sc->sysctl_ctx, 187 SYSCTL_CHILDREN(device_get_sysctl_tree(parent)), 188 OID_AUTO, "freq_levels", 189 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, sc, 0, 190 cpufreq_levels_sysctl, "A", "CPU frequency levels"); 191 192 /* 193 * Queue a one-shot broadcast that levels have changed. 194 * It will run once the system has completed booting. 195 */ 196 TASK_INIT(&sc->startup_task, 0, cpufreq_startup_task, dev); 197 taskqueue_enqueue(taskqueue_thread, &sc->startup_task); 198 199 return (0); 200} 201 202/* Handle any work to be done for all drivers that attached during boot. */ 203static void 204cpufreq_startup_task(void *ctx, int pending) 205{ 206 207 cpufreq_settings_changed((device_t)ctx); 208} 209 210static int 211cpufreq_detach(device_t dev) 212{ 213 struct cpufreq_softc *sc; 214 struct cf_saved_freq *saved_freq; 215 216 CF_DEBUG("shutdown %s\n", device_get_nameunit(dev)); 217 sc = device_get_softc(dev); 218 sysctl_ctx_free(&sc->sysctl_ctx); 219 220 while ((saved_freq = SLIST_FIRST(&sc->saved_freq)) != NULL) { 221 SLIST_REMOVE_HEAD(&sc->saved_freq, link); 222 free(saved_freq, M_TEMP); 223 } 224 225 free(sc->levels_buf, M_DEVBUF); 226 227 return (0); 228} 229 230static int 231cf_set_method(device_t dev, const struct cf_level *level, int priority) 232{ 233 struct cpufreq_softc *sc; 234 const struct cf_setting *set; 235 struct cf_saved_freq *saved_freq, *curr_freq; 236 struct pcpu *pc; 237 int error, i; 238 u_char pri; 239 240 sc = device_get_softc(dev); 241 error = 0; 242 set = NULL; 243 saved_freq = NULL; 244 245 /* We are going to change levels so notify the pre-change handler. */ 246 EVENTHANDLER_INVOKE(cpufreq_pre_change, level, &error); 247 if (error != 0) { 248 EVENTHANDLER_INVOKE(cpufreq_post_change, level, error); 249 return (error); 250 } 251 252 CF_MTX_LOCK(&sc->lock); 253 254#ifdef SMP 255#ifdef EARLY_AP_STARTUP 256 MPASS(mp_ncpus == 1 || smp_started); 257#else 258 /* 259 * If still booting and secondary CPUs not started yet, don't allow 260 * changing the frequency until they're online. This is because we 261 * can't switch to them using sched_bind() and thus we'd only be 262 * switching the main CPU. XXXTODO: Need to think more about how to 263 * handle having different CPUs at different frequencies. 264 */ 265 if (mp_ncpus > 1 && !smp_started) { 266 device_printf(dev, "rejecting change, SMP not started yet\n"); 267 error = ENXIO; 268 goto out; 269 } 270#endif 271#endif /* SMP */ 272 273 /* 274 * If the requested level has a lower priority, don't allow 275 * the new level right now. 276 */ 277 if (priority < sc->curr_priority) { 278 CF_DEBUG("ignoring, curr prio %d less than %d\n", priority, 279 sc->curr_priority); 280 error = EPERM; 281 goto out; 282 } 283 284 /* 285 * If the caller didn't specify a level and one is saved, prepare to 286 * restore the saved level. If none has been saved, return an error. 287 */ 288 if (level == NULL) { 289 saved_freq = SLIST_FIRST(&sc->saved_freq); 290 if (saved_freq == NULL) { 291 CF_DEBUG("NULL level, no saved level\n"); 292 error = ENXIO; 293 goto out; 294 } 295 level = &saved_freq->level; 296 priority = saved_freq->priority; 297 CF_DEBUG("restoring saved level, freq %d prio %d\n", 298 level->total_set.freq, priority); 299 } 300 301 /* Reject levels that are below our specified threshold. */ 302 if (level->total_set.freq < cf_lowest_freq) { 303 CF_DEBUG("rejecting freq %d, less than %d limit\n", 304 level->total_set.freq, cf_lowest_freq); 305 error = EINVAL; 306 goto out; 307 } 308 309 /* If already at this level, just return. */ 310 if (sc->curr_level.total_set.freq == level->total_set.freq) { 311 CF_DEBUG("skipping freq %d, same as current level %d\n", 312 level->total_set.freq, sc->curr_level.total_set.freq); 313 goto skip; 314 } 315 316 /* First, set the absolute frequency via its driver. */ 317 set = &level->abs_set; 318 if (set->dev) { 319 if (!device_is_attached(set->dev)) { 320 error = ENXIO; 321 goto out; 322 } 323 324 /* Bind to the target CPU before switching. */ 325 pc = cpu_get_pcpu(set->dev); 326 327 /* Skip settings if CPU is not started. */ 328 if (pc == NULL) { 329 error = 0; 330 goto out; 331 } 332 thread_lock(curthread); 333 pri = curthread->td_priority; 334 sched_prio(curthread, PRI_MIN); 335 sched_bind(curthread, pc->pc_cpuid); 336 thread_unlock(curthread); 337 CF_DEBUG("setting abs freq %d on %s (cpu %d)\n", set->freq, 338 device_get_nameunit(set->dev), PCPU_GET(cpuid)); 339 error = CPUFREQ_DRV_SET(set->dev, set); 340 thread_lock(curthread); 341 sched_unbind(curthread); 342 sched_prio(curthread, pri); 343 thread_unlock(curthread); 344 if (error) { 345 goto out; 346 } 347 } 348 349 /* Next, set any/all relative frequencies via their drivers. */ 350 for (i = 0; i < level->rel_count; i++) { 351 set = &level->rel_set[i]; 352 if (!device_is_attached(set->dev)) { 353 error = ENXIO; 354 goto out; 355 } 356 357 /* Bind to the target CPU before switching. */ 358 pc = cpu_get_pcpu(set->dev); 359 thread_lock(curthread); 360 pri = curthread->td_priority; 361 sched_prio(curthread, PRI_MIN); 362 sched_bind(curthread, pc->pc_cpuid); 363 thread_unlock(curthread); 364 CF_DEBUG("setting rel freq %d on %s (cpu %d)\n", set->freq, 365 device_get_nameunit(set->dev), PCPU_GET(cpuid)); 366 error = CPUFREQ_DRV_SET(set->dev, set); 367 thread_lock(curthread); 368 sched_unbind(curthread); 369 sched_prio(curthread, pri); 370 thread_unlock(curthread); 371 if (error) { 372 /* XXX Back out any successful setting? */ 373 goto out; 374 } 375 } 376 377skip: 378 /* 379 * Before recording the current level, check if we're going to a 380 * higher priority. If so, save the previous level and priority. 381 */ 382 if (sc->curr_level.total_set.freq != CPUFREQ_VAL_UNKNOWN && 383 priority > sc->curr_priority) { 384 CF_DEBUG("saving level, freq %d prio %d\n", 385 sc->curr_level.total_set.freq, sc->curr_priority); 386 curr_freq = malloc(sizeof(*curr_freq), M_TEMP, M_NOWAIT); 387 if (curr_freq == NULL) { 388 error = ENOMEM; 389 goto out; 390 } 391 curr_freq->level = sc->curr_level; 392 curr_freq->priority = sc->curr_priority; 393 SLIST_INSERT_HEAD(&sc->saved_freq, curr_freq, link); 394 } 395 sc->curr_level = *level; 396 sc->curr_priority = priority; 397 398 /* If we were restoring a saved state, reset it to "unused". */ 399 if (saved_freq != NULL) { 400 CF_DEBUG("resetting saved level\n"); 401 sc->curr_level.total_set.freq = CPUFREQ_VAL_UNKNOWN; 402 SLIST_REMOVE_HEAD(&sc->saved_freq, link); 403 free(saved_freq, M_TEMP); 404 } 405 406out: 407 CF_MTX_UNLOCK(&sc->lock); 408 409 /* 410 * We changed levels (or attempted to) so notify the post-change 411 * handler of new frequency or error. 412 */ 413 EVENTHANDLER_INVOKE(cpufreq_post_change, level, error); 414 if (error && set) 415 device_printf(set->dev, "set freq failed, err %d\n", error); 416 417 return (error); 418} 419 420static int 421cpufreq_get_frequency(device_t dev) 422{ 423 struct cf_setting set; 424 425 if (CPUFREQ_DRV_GET(dev, &set) != 0) 426 return (-1); 427 428 return (set.freq); 429} 430 431/* Returns the index into *levels with the match */ 432static int 433cpufreq_get_level(device_t dev, struct cf_level *levels, int count) 434{ 435 int i, freq; 436 437 if ((freq = cpufreq_get_frequency(dev)) < 0) 438 return (-1); 439 for (i = 0; i < count; i++) 440 if (freq == levels[i].total_set.freq) 441 return (i); 442 443 return (-1); 444} 445 446/* 447 * Used by the cpufreq core, this function will populate *level with the current 448 * frequency as either determined by a cached value sc->curr_level, or in the 449 * case the lower level driver has set the CPUFREQ_FLAG_UNCACHED flag, it will 450 * obtain the frequency from the driver itself. 451 */ 452static int 453cf_get_method(device_t dev, struct cf_level *level) 454{ 455 struct cpufreq_softc *sc; 456 struct cf_level *levels; 457 struct cf_setting *curr_set; 458 struct pcpu *pc; 459 int bdiff, count, diff, error, i, type; 460 uint64_t rate; 461 462 sc = device_get_softc(dev); 463 error = 0; 464 levels = NULL; 465 466 /* 467 * If we already know the current frequency, and the driver didn't ask 468 * for uncached usage, we're done. 469 */ 470 CF_MTX_LOCK(&sc->lock); 471 curr_set = &sc->curr_level.total_set; 472 error = CPUFREQ_DRV_TYPE(sc->cf_drv_dev, &type); 473 if (error == 0 && (type & CPUFREQ_FLAG_UNCACHED)) { 474 struct cf_setting set; 475 476 /* 477 * If the driver wants to always report back the real frequency, 478 * first try the driver and if that fails, fall back to 479 * estimating. 480 */ 481 if (CPUFREQ_DRV_GET(sc->cf_drv_dev, &set) == 0) { 482 sc->curr_level.total_set = set; 483 CF_DEBUG("get returning immediate freq %d\n", 484 curr_set->freq); 485 goto out; 486 } 487 } else if (curr_set->freq != CPUFREQ_VAL_UNKNOWN) { 488 CF_DEBUG("get returning known freq %d\n", curr_set->freq); 489 error = 0; 490 goto out; 491 } 492 CF_MTX_UNLOCK(&sc->lock); 493 494 /* 495 * We need to figure out the current level. Loop through every 496 * driver, getting the current setting. Then, attempt to get a best 497 * match of settings against each level. 498 */ 499 count = CF_MAX_LEVELS; 500 levels = malloc(count * sizeof(*levels), M_TEMP, M_NOWAIT); 501 if (levels == NULL) 502 return (ENOMEM); 503 error = CPUFREQ_LEVELS(sc->dev, levels, &count); 504 if (error) { 505 if (error == E2BIG) 506 printf("cpufreq: need to increase CF_MAX_LEVELS\n"); 507 free(levels, M_TEMP); 508 return (error); 509 } 510 511 /* 512 * Reacquire the lock and search for the given level. 513 * 514 * XXX Note: this is not quite right since we really need to go 515 * through each level and compare both absolute and relative 516 * settings for each driver in the system before making a match. 517 * The estimation code below catches this case though. 518 */ 519 CF_MTX_LOCK(&sc->lock); 520 i = cpufreq_get_level(sc->cf_drv_dev, levels, count); 521 if (i >= 0) 522 sc->curr_level = levels[i]; 523 else 524 CF_DEBUG("Couldn't find supported level for %s\n", 525 device_get_nameunit(sc->cf_drv_dev)); 526 527 if (curr_set->freq != CPUFREQ_VAL_UNKNOWN) { 528 CF_DEBUG("get matched freq %d from drivers\n", curr_set->freq); 529 goto out; 530 } 531 532 /* 533 * We couldn't find an exact match, so attempt to estimate and then 534 * match against a level. 535 */ 536 pc = cpu_get_pcpu(dev); 537 if (pc == NULL) { 538 error = ENXIO; 539 goto out; 540 } 541 cpu_est_clockrate(pc->pc_cpuid, &rate); 542 rate /= 1000000; 543 bdiff = 1 << 30; 544 for (i = 0; i < count; i++) { 545 diff = abs(levels[i].total_set.freq - rate); 546 if (diff < bdiff) { 547 bdiff = diff; 548 sc->curr_level = levels[i]; 549 } 550 } 551 CF_DEBUG("get estimated freq %d\n", curr_set->freq); 552 553out: 554 if (error == 0) 555 *level = sc->curr_level; 556 557 CF_MTX_UNLOCK(&sc->lock); 558 if (levels) 559 free(levels, M_TEMP); 560 return (error); 561} 562 563/* 564 * Either directly obtain settings from the cpufreq driver, or build a list of 565 * relative settings to be integrated later against an absolute max. 566 */ 567static int 568cpufreq_add_levels(device_t cf_dev, struct cf_setting_lst *rel_sets) 569{ 570 struct cf_setting_array *set_arr; 571 struct cf_setting *sets; 572 device_t dev; 573 struct cpufreq_softc *sc; 574 int type, set_count, error; 575 576 sc = device_get_softc(cf_dev); 577 dev = sc->cf_drv_dev; 578 579 /* Skip devices that aren't ready. */ 580 if (!device_is_attached(cf_dev)) 581 return (0); 582 583 /* 584 * Get settings, skipping drivers that offer no settings or 585 * provide settings for informational purposes only. 586 */ 587 error = CPUFREQ_DRV_TYPE(dev, &type); 588 if (error != 0 || (type & CPUFREQ_FLAG_INFO_ONLY)) { 589 if (error == 0) { 590 CF_DEBUG("skipping info-only driver %s\n", 591 device_get_nameunit(cf_dev)); 592 } 593 return (error); 594 } 595 596 sets = malloc(MAX_SETTINGS * sizeof(*sets), M_TEMP, M_NOWAIT); 597 if (sets == NULL) 598 return (ENOMEM); 599 600 set_count = MAX_SETTINGS; 601 error = CPUFREQ_DRV_SETTINGS(dev, sets, &set_count); 602 if (error != 0 || set_count == 0) 603 goto out; 604 605 /* Add the settings to our absolute/relative lists. */ 606 switch (type & CPUFREQ_TYPE_MASK) { 607 case CPUFREQ_TYPE_ABSOLUTE: 608 error = cpufreq_insert_abs(sc, sets, set_count); 609 break; 610 case CPUFREQ_TYPE_RELATIVE: 611 CF_DEBUG("adding %d relative settings\n", set_count); 612 set_arr = malloc(sizeof(*set_arr), M_TEMP, M_NOWAIT); 613 if (set_arr == NULL) { 614 error = ENOMEM; 615 goto out; 616 } 617 bcopy(sets, set_arr->sets, set_count * sizeof(*sets)); 618 set_arr->count = set_count; 619 TAILQ_INSERT_TAIL(rel_sets, set_arr, link); 620 break; 621 default: 622 error = EINVAL; 623 } 624 625out: 626 free(sets, M_TEMP); 627 return (error); 628} 629 630static int 631cf_levels_method(device_t dev, struct cf_level *levels, int *count) 632{ 633 struct cf_setting_array *set_arr; 634 struct cf_setting_lst rel_sets; 635 struct cpufreq_softc *sc; 636 struct cf_level *lev; 637 struct pcpu *pc; 638 int error, i; 639 uint64_t rate; 640 641 if (levels == NULL || count == NULL) 642 return (EINVAL); 643 644 TAILQ_INIT(&rel_sets); 645 sc = device_get_softc(dev); 646 647 CF_MTX_LOCK(&sc->lock); 648 error = cpufreq_add_levels(sc->dev, &rel_sets); 649 if (error) 650 goto out; 651 652 /* 653 * If there are no absolute levels, create a fake one at 100%. We 654 * then cache the clockrate for later use as our base frequency. 655 */ 656 if (TAILQ_EMPTY(&sc->all_levels)) { 657 struct cf_setting set; 658 659 CF_DEBUG("No absolute levels returned by driver\n"); 660 661 if (sc->max_mhz == CPUFREQ_VAL_UNKNOWN) { 662 sc->max_mhz = cpu_get_nominal_mhz(dev); 663 /* 664 * If the CPU can't report a rate for 100%, hope 665 * the CPU is running at its nominal rate right now, 666 * and use that instead. 667 */ 668 if (sc->max_mhz <= 0) { 669 pc = cpu_get_pcpu(dev); 670 cpu_est_clockrate(pc->pc_cpuid, &rate); 671 sc->max_mhz = rate / 1000000; 672 } 673 } 674 memset(&set, CPUFREQ_VAL_UNKNOWN, sizeof(set)); 675 set.freq = sc->max_mhz; 676 set.dev = NULL; 677 error = cpufreq_insert_abs(sc, &set, 1); 678 if (error) 679 goto out; 680 } 681 682 /* Create a combined list of absolute + relative levels. */ 683 TAILQ_FOREACH(set_arr, &rel_sets, link) 684 cpufreq_expand_set(sc, set_arr); 685 686 /* If the caller doesn't have enough space, return the actual count. */ 687 if (sc->all_count > *count) { 688 *count = sc->all_count; 689 error = E2BIG; 690 goto out; 691 } 692 693 /* Finally, output the list of levels. */ 694 i = 0; 695 TAILQ_FOREACH(lev, &sc->all_levels, link) { 696 /* Skip levels that have a frequency that is too low. */ 697 if (lev->total_set.freq < cf_lowest_freq) { 698 sc->all_count--; 699 continue; 700 } 701 702 levels[i] = *lev; 703 i++; 704 } 705 *count = sc->all_count; 706 error = 0; 707 708out: 709 /* Clear all levels since we regenerate them each time. */ 710 while ((lev = TAILQ_FIRST(&sc->all_levels)) != NULL) { 711 TAILQ_REMOVE(&sc->all_levels, lev, link); 712 free(lev, M_TEMP); 713 } 714 sc->all_count = 0; 715 716 CF_MTX_UNLOCK(&sc->lock); 717 while ((set_arr = TAILQ_FIRST(&rel_sets)) != NULL) { 718 TAILQ_REMOVE(&rel_sets, set_arr, link); 719 free(set_arr, M_TEMP); 720 } 721 return (error); 722} 723 724/* 725 * Create levels for an array of absolute settings and insert them in 726 * sorted order in the specified list. 727 */ 728static int 729cpufreq_insert_abs(struct cpufreq_softc *sc, struct cf_setting *sets, 730 int count) 731{ 732 struct cf_level_lst *list; 733 struct cf_level *level, *search; 734 int i, inserted; 735 736 CF_MTX_ASSERT(&sc->lock); 737 738 list = &sc->all_levels; 739 for (i = 0; i < count; i++) { 740 level = malloc(sizeof(*level), M_TEMP, M_NOWAIT | M_ZERO); 741 if (level == NULL) 742 return (ENOMEM); 743 level->abs_set = sets[i]; 744 level->total_set = sets[i]; 745 level->total_set.dev = NULL; 746 sc->all_count++; 747 inserted = 0; 748 749 if (TAILQ_EMPTY(list)) { 750 CF_DEBUG("adding abs setting %d at head\n", 751 sets[i].freq); 752 TAILQ_INSERT_HEAD(list, level, link); 753 continue; 754 } 755 756 TAILQ_FOREACH_REVERSE(search, list, cf_level_lst, link) 757 if (sets[i].freq <= search->total_set.freq) { 758 CF_DEBUG("adding abs setting %d after %d\n", 759 sets[i].freq, search->total_set.freq); 760 TAILQ_INSERT_AFTER(list, search, level, link); 761 inserted = 1; 762 break; 763 } 764 765 if (inserted == 0) { 766 TAILQ_FOREACH(search, list, link) 767 if (sets[i].freq >= search->total_set.freq) { 768 CF_DEBUG("adding abs setting %d before %d\n", 769 sets[i].freq, search->total_set.freq); 770 TAILQ_INSERT_BEFORE(search, level, link); 771 break; 772 } 773 } 774 } 775 776 return (0); 777} 778 779/* 780 * Expand a group of relative settings, creating derived levels from them. 781 */ 782static int 783cpufreq_expand_set(struct cpufreq_softc *sc, struct cf_setting_array *set_arr) 784{ 785 struct cf_level *fill, *search; 786 struct cf_setting *set; 787 int i; 788 789 CF_MTX_ASSERT(&sc->lock); 790 791 /* 792 * Walk the set of all existing levels in reverse. This is so we 793 * create derived states from the lowest absolute settings first 794 * and discard duplicates created from higher absolute settings. 795 * For instance, a level of 50 Mhz derived from 100 Mhz + 50% is 796 * preferable to 200 Mhz + 25% because absolute settings are more 797 * efficient since they often change the voltage as well. 798 */ 799 TAILQ_FOREACH_REVERSE(search, &sc->all_levels, cf_level_lst, link) { 800 /* Add each setting to the level, duplicating if necessary. */ 801 for (i = 0; i < set_arr->count; i++) { 802 set = &set_arr->sets[i]; 803 804 /* 805 * If this setting is less than 100%, split the level 806 * into two and add this setting to the new level. 807 */ 808 fill = search; 809 if (set->freq < 10000) { 810 fill = cpufreq_dup_set(sc, search, set); 811 812 /* 813 * The new level was a duplicate of an existing 814 * level or its absolute setting is too high 815 * so we freed it. For example, we discard a 816 * derived level of 1000 MHz/25% if a level 817 * of 500 MHz/100% already exists. 818 */ 819 if (fill == NULL) 820 break; 821 } 822 823 /* Add this setting to the existing or new level. */ 824 KASSERT(fill->rel_count < MAX_SETTINGS, 825 ("cpufreq: too many relative drivers (%d)", 826 MAX_SETTINGS)); 827 fill->rel_set[fill->rel_count] = *set; 828 fill->rel_count++; 829 CF_DEBUG( 830 "expand set added rel setting %d%% to %d level\n", 831 set->freq / 100, fill->total_set.freq); 832 } 833 } 834 835 return (0); 836} 837 838static struct cf_level * 839cpufreq_dup_set(struct cpufreq_softc *sc, struct cf_level *dup, 840 struct cf_setting *set) 841{ 842 struct cf_level_lst *list; 843 struct cf_level *fill, *itr; 844 struct cf_setting *fill_set, *itr_set; 845 int i; 846 847 CF_MTX_ASSERT(&sc->lock); 848 849 /* 850 * Create a new level, copy it from the old one, and update the 851 * total frequency and power by the percentage specified in the 852 * relative setting. 853 */ 854 fill = malloc(sizeof(*fill), M_TEMP, M_NOWAIT); 855 if (fill == NULL) 856 return (NULL); 857 *fill = *dup; 858 fill_set = &fill->total_set; 859 fill_set->freq = 860 ((uint64_t)fill_set->freq * set->freq) / 10000; 861 if (fill_set->power != CPUFREQ_VAL_UNKNOWN) { 862 fill_set->power = ((uint64_t)fill_set->power * set->freq) 863 / 10000; 864 } 865 if (set->lat != CPUFREQ_VAL_UNKNOWN) { 866 if (fill_set->lat != CPUFREQ_VAL_UNKNOWN) 867 fill_set->lat += set->lat; 868 else 869 fill_set->lat = set->lat; 870 } 871 CF_DEBUG("dup set considering derived setting %d\n", fill_set->freq); 872 873 /* 874 * If we copied an old level that we already modified (say, at 100%), 875 * we need to remove that setting before adding this one. Since we 876 * process each setting array in order, we know any settings for this 877 * driver will be found at the end. 878 */ 879 for (i = fill->rel_count; i != 0; i--) { 880 if (fill->rel_set[i - 1].dev != set->dev) 881 break; 882 CF_DEBUG("removed last relative driver: %s\n", 883 device_get_nameunit(set->dev)); 884 fill->rel_count--; 885 } 886 887 /* 888 * Insert the new level in sorted order. If it is a duplicate of an 889 * existing level (1) or has an absolute setting higher than the 890 * existing level (2), do not add it. We can do this since any such 891 * level is guaranteed use less power. For example (1), a level with 892 * one absolute setting of 800 Mhz uses less power than one composed 893 * of an absolute setting of 1600 Mhz and a relative setting at 50%. 894 * Also for example (2), a level of 800 Mhz/75% is preferable to 895 * 1600 Mhz/25% even though the latter has a lower total frequency. 896 */ 897 list = &sc->all_levels; 898 KASSERT(!TAILQ_EMPTY(list), ("all levels list empty in dup set")); 899 TAILQ_FOREACH_REVERSE(itr, list, cf_level_lst, link) { 900 itr_set = &itr->total_set; 901 if (CPUFREQ_CMP(fill_set->freq, itr_set->freq)) { 902 CF_DEBUG("dup set rejecting %d (dupe)\n", 903 fill_set->freq); 904 itr = NULL; 905 break; 906 } else if (fill_set->freq < itr_set->freq) { 907 if (fill->abs_set.freq <= itr->abs_set.freq) { 908 CF_DEBUG( 909 "dup done, inserting new level %d after %d\n", 910 fill_set->freq, itr_set->freq); 911 TAILQ_INSERT_AFTER(list, itr, fill, link); 912 sc->all_count++; 913 } else { 914 CF_DEBUG("dup set rejecting %d (abs too big)\n", 915 fill_set->freq); 916 itr = NULL; 917 } 918 break; 919 } 920 } 921 922 /* We didn't find a good place for this new level so free it. */ 923 if (itr == NULL) { 924 CF_DEBUG("dup set freeing new level %d (not optimal)\n", 925 fill_set->freq); 926 free(fill, M_TEMP); 927 fill = NULL; 928 } 929 930 return (fill); 931} 932 933static int 934cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS) 935{ 936 struct cpufreq_softc *sc; 937 struct cf_level *levels; 938 int best, count, diff, bdiff, devcount, error, freq, i, n; 939 device_t *devs; 940 941 devs = NULL; 942 sc = oidp->oid_arg1; 943 levels = sc->levels_buf; 944 945 error = CPUFREQ_GET(sc->dev, &levels[0]); 946 if (error) 947 goto out; 948 freq = levels[0].total_set.freq; 949 error = sysctl_handle_int(oidp, &freq, 0, req); 950 if (error != 0 || req->newptr == NULL) 951 goto out; 952 953 /* 954 * While we only call cpufreq_get() on one device (assuming all 955 * CPUs have equal levels), we call cpufreq_set() on all CPUs. 956 * This is needed for some MP systems. 957 */ 958 error = devclass_get_devices(devclass_find("cpufreq"), &devs, &devcount); 959 if (error) 960 goto out; 961 for (n = 0; n < devcount; n++) { 962 count = CF_MAX_LEVELS; 963 error = CPUFREQ_LEVELS(devs[n], levels, &count); 964 if (error) { 965 if (error == E2BIG) 966 printf( 967 "cpufreq: need to increase CF_MAX_LEVELS\n"); 968 break; 969 } 970 best = 0; 971 bdiff = 1 << 30; 972 for (i = 0; i < count; i++) { 973 diff = abs(levels[i].total_set.freq - freq); 974 if (diff < bdiff) { 975 bdiff = diff; 976 best = i; 977 } 978 } 979 error = CPUFREQ_SET(devs[n], &levels[best], CPUFREQ_PRIO_USER); 980 } 981 982out: 983 if (devs) 984 free(devs, M_TEMP); 985 return (error); 986} 987 988static int 989cpufreq_levels_sysctl(SYSCTL_HANDLER_ARGS) 990{ 991 struct cpufreq_softc *sc; 992 struct cf_level *levels; 993 struct cf_setting *set; 994 struct sbuf sb; 995 int count, error, i; 996 997 sc = oidp->oid_arg1; 998 sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND); 999 1000 /* Get settings from the device and generate the output string. */ 1001 count = CF_MAX_LEVELS; 1002 levels = sc->levels_buf; 1003 if (levels == NULL) { 1004 sbuf_delete(&sb); 1005 return (ENOMEM); 1006 } 1007 error = CPUFREQ_LEVELS(sc->dev, levels, &count); 1008 if (error) { 1009 if (error == E2BIG) 1010 printf("cpufreq: need to increase CF_MAX_LEVELS\n"); 1011 goto out; 1012 } 1013 if (count) { 1014 for (i = 0; i < count; i++) { 1015 set = &levels[i].total_set; 1016 sbuf_printf(&sb, "%d/%d ", set->freq, set->power); 1017 } 1018 } else 1019 sbuf_cpy(&sb, "0"); 1020 sbuf_trim(&sb); 1021 sbuf_finish(&sb); 1022 error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req); 1023 1024out: 1025 sbuf_delete(&sb); 1026 return (error); 1027} 1028 1029static int 1030cpufreq_settings_sysctl(SYSCTL_HANDLER_ARGS) 1031{ 1032 device_t dev; 1033 struct cf_setting *sets; 1034 struct sbuf sb; 1035 int error, i, set_count; 1036 1037 dev = oidp->oid_arg1; 1038 sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND); 1039 1040 /* Get settings from the device and generate the output string. */ 1041 set_count = MAX_SETTINGS; 1042 sets = malloc(set_count * sizeof(*sets), M_TEMP, M_NOWAIT); 1043 if (sets == NULL) { 1044 sbuf_delete(&sb); 1045 return (ENOMEM); 1046 } 1047 error = CPUFREQ_DRV_SETTINGS(dev, sets, &set_count); 1048 if (error) 1049 goto out; 1050 if (set_count) { 1051 for (i = 0; i < set_count; i++) 1052 sbuf_printf(&sb, "%d/%d ", sets[i].freq, sets[i].power); 1053 } else 1054 sbuf_cpy(&sb, "0"); 1055 sbuf_trim(&sb); 1056 sbuf_finish(&sb); 1057 error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req); 1058 1059out: 1060 free(sets, M_TEMP); 1061 sbuf_delete(&sb); 1062 return (error); 1063} 1064 1065static void 1066cpufreq_add_freq_driver_sysctl(device_t cf_dev) 1067{ 1068 struct cpufreq_softc *sc; 1069 1070 sc = device_get_softc(cf_dev); 1071 SYSCTL_ADD_CONST_STRING(&sc->sysctl_ctx, 1072 SYSCTL_CHILDREN(device_get_sysctl_tree(cf_dev)), OID_AUTO, 1073 "freq_driver", CTLFLAG_RD, device_get_nameunit(sc->cf_drv_dev), 1074 "cpufreq driver used by this cpu"); 1075} 1076 1077int 1078cpufreq_register(device_t dev) 1079{ 1080 struct cpufreq_softc *sc; 1081 device_t cf_dev, cpu_dev; 1082 int error; 1083 1084 /* Add a sysctl to get each driver's settings separately. */ 1085 SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev), 1086 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 1087 OID_AUTO, "freq_settings", 1088 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT, dev, 0, 1089 cpufreq_settings_sysctl, "A", "CPU frequency driver settings"); 1090 1091 /* 1092 * Add only one cpufreq device to each CPU. Currently, all CPUs 1093 * must offer the same levels and be switched at the same time. 1094 */ 1095 cpu_dev = device_get_parent(dev); 1096 if ((cf_dev = device_find_child(cpu_dev, "cpufreq", -1))) { 1097 sc = device_get_softc(cf_dev); 1098 sc->max_mhz = CPUFREQ_VAL_UNKNOWN; 1099 MPASS(sc->cf_drv_dev != NULL); 1100 return (0); 1101 } 1102 1103 /* Add the child device and possibly sysctls. */ 1104 cf_dev = BUS_ADD_CHILD(cpu_dev, 0, "cpufreq", device_get_unit(cpu_dev)); 1105 if (cf_dev == NULL) 1106 return (ENOMEM); 1107 device_quiet(cf_dev); 1108 1109 error = device_probe_and_attach(cf_dev); 1110 if (error) 1111 return (error); 1112 1113 sc = device_get_softc(cf_dev); 1114 sc->cf_drv_dev = dev; 1115 cpufreq_add_freq_driver_sysctl(cf_dev); 1116 return (error); 1117} 1118 1119int 1120cpufreq_unregister(device_t dev) 1121{ 1122 device_t cf_dev; 1123 struct cpufreq_softc *sc __diagused; 1124 1125 /* 1126 * If this is the last cpufreq child device, remove the control 1127 * device as well. We identify cpufreq children by calling a method 1128 * they support. 1129 */ 1130 cf_dev = device_find_child(device_get_parent(dev), "cpufreq", -1); 1131 if (cf_dev == NULL) { 1132 device_printf(dev, 1133 "warning: cpufreq_unregister called with no cpufreq device active\n"); 1134 return (0); 1135 } 1136 sc = device_get_softc(cf_dev); 1137 MPASS(sc->cf_drv_dev == dev); 1138 device_delete_child(device_get_parent(cf_dev), cf_dev); 1139 1140 return (0); 1141} 1142 1143int 1144cpufreq_settings_changed(device_t dev) 1145{ 1146 1147 EVENTHANDLER_INVOKE(cpufreq_levels_changed, 1148 device_get_unit(device_get_parent(dev))); 1149 return (0); 1150} 1151