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("$FreeBSD$"); 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 62 struct cf_saved_freq { 63 struct cf_level level; 64 int priority; 65 SLIST_ENTRY(cf_saved_freq) link; 66 }; 67 68 struct 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 82 struct cf_setting_array { 83 struct cf_setting sets[MAX_SETTINGS]; 84 int count; 85 TAILQ_ENTRY(cf_setting_array) link; 86 }; 87 88 TAILQ_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) 99 100 static int cpufreq_attach(device_t dev); 101 static void cpufreq_startup_task(void *ctx, int pending); 102 static int cpufreq_detach(device_t dev); 103 static int cf_set_method(device_t dev, const struct cf_level *level, 104 int priority); 105 static int cf_get_method(device_t dev, struct cf_level *level); 106 static int cf_levels_method(device_t dev, struct cf_level *levels, 107 int *count); 108 static int cpufreq_insert_abs(struct cpufreq_softc *sc, 109 struct cf_setting *sets, int count); 110 static int cpufreq_expand_set(struct cpufreq_softc *sc, 111 struct cf_setting_array *set_arr); 112 static struct cf_level *cpufreq_dup_set(struct cpufreq_softc *sc, 113 struct cf_level *dup, struct cf_setting *set); 114 static int cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS); 115 static int cpufreq_levels_sysctl(SYSCTL_HANDLER_ARGS); 116 static int cpufreq_settings_sysctl(SYSCTL_HANDLER_ARGS); 117 118 static 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 static driver_t cpufreq_driver = { 129 "cpufreq", cpufreq_methods, sizeof(struct cpufreq_softc) 130 }; 131 static devclass_t cpufreq_dc; 132 DRIVER_MODULE(cpufreq, cpu, cpufreq_driver, cpufreq_dc, 0, 0); 133 134 static int cf_lowest_freq; 135 static int cf_verbose; 136 TUNABLE_INT("debug.cpufreq.lowest", &cf_lowest_freq); 137 TUNABLE_INT("debug.cpufreq.verbose", &cf_verbose); 138 static SYSCTL_NODE(_debug, OID_AUTO, cpufreq, CTLFLAG_RD, NULL, 139 "cpufreq debugging"); 140 SYSCTL_INT(_debug_cpufreq, OID_AUTO, lowest, CTLFLAG_RW, &cf_lowest_freq, 1, 141 "Don't provide levels below this frequency."); 142 SYSCTL_INT(_debug_cpufreq, OID_AUTO, verbose, CTLFLAG_RW, &cf_verbose, 1, 143 "Print verbose debugging messages"); 144 145 static int 146 cpufreq_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. */ 207 static void 208 cpufreq_startup_task(void *ctx, int pending) 209 { 210 211 cpufreq_settings_changed((device_t)ctx); 212 } 213 214 static int 215 cpufreq_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 } 239 240 static int 241 cf_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_started) { 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 } 369 370 skip: 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 } 398 399 out: 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 } 412 413 static int 414 cf_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 bdiff, count, diff, 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 bdiff = 1 << 30; 498 for (i = 0; i < count; i++) { 499 diff = abs(levels[i].total_set.freq - rate); 500 if (diff < bdiff) { 501 bdiff = diff; 502 sc->curr_level = levels[i]; 503 } 504 } 505 CF_DEBUG("get estimated freq %d\n", curr_set->freq); 506 507 out: 508 if (error == 0) 509 *level = sc->curr_level; 510 511 CF_MTX_UNLOCK(&sc->lock); 512 if (levels) 513 free(levels, M_TEMP); 514 return (error); 515 } 516 517 static int 518 cf_levels_method(device_t dev, struct cf_level *levels, int *count) 519 { 520 struct cf_setting_array *set_arr; 521 struct cf_setting_lst rel_sets; 522 struct cpufreq_softc *sc; 523 struct cf_level *lev; 524 struct cf_setting *sets; 525 struct pcpu *pc; 526 device_t *devs; 527 int error, i, numdevs, set_count, type; 528 uint64_t rate; 529 530 if (levels == NULL || count == NULL) 531 return (EINVAL); 532 533 TAILQ_INIT(&rel_sets); 534 sc = device_get_softc(dev); 535 error = device_get_children(device_get_parent(dev), &devs, &numdevs); 536 if (error) 537 return (error); 538 sets = malloc(MAX_SETTINGS * sizeof(*sets), M_TEMP, M_NOWAIT); 539 if (sets == NULL) { 540 free(devs, M_TEMP); 541 return (ENOMEM); 542 } 543 544 /* Get settings from all cpufreq drivers. */ 545 CF_MTX_LOCK(&sc->lock); 546 for (i = 0; i < numdevs; i++) { 547 /* Skip devices that aren't ready. */ 548 if (!device_is_attached(devs[i])) 549 continue; 550 551 /* 552 * Get settings, skipping drivers that offer no settings or 553 * provide settings for informational purposes only. 554 */ 555 error = CPUFREQ_DRV_TYPE(devs[i], &type); 556 if (error || (type & CPUFREQ_FLAG_INFO_ONLY)) { 557 if (error == 0) { 558 CF_DEBUG("skipping info-only driver %s\n", 559 device_get_nameunit(devs[i])); 560 } 561 continue; 562 } 563 set_count = MAX_SETTINGS; 564 error = CPUFREQ_DRV_SETTINGS(devs[i], sets, &set_count); 565 if (error || set_count == 0) 566 continue; 567 568 /* Add the settings to our absolute/relative lists. */ 569 switch (type & CPUFREQ_TYPE_MASK) { 570 case CPUFREQ_TYPE_ABSOLUTE: 571 error = cpufreq_insert_abs(sc, sets, set_count); 572 break; 573 case CPUFREQ_TYPE_RELATIVE: 574 CF_DEBUG("adding %d relative settings\n", set_count); 575 set_arr = malloc(sizeof(*set_arr), M_TEMP, M_NOWAIT); 576 if (set_arr == NULL) { 577 error = ENOMEM; 578 goto out; 579 } 580 bcopy(sets, set_arr->sets, set_count * sizeof(*sets)); 581 set_arr->count = set_count; 582 TAILQ_INSERT_TAIL(&rel_sets, set_arr, link); 583 break; 584 default: 585 error = EINVAL; 586 } 587 if (error) 588 goto out; 589 } 590 591 /* 592 * If there are no absolute levels, create a fake one at 100%. We 593 * then cache the clockrate for later use as our base frequency. 594 */ 595 if (TAILQ_EMPTY(&sc->all_levels)) { 596 if (sc->max_mhz == CPUFREQ_VAL_UNKNOWN) { 597 sc->max_mhz = cpu_get_nominal_mhz(dev); 598 /* 599 * If the CPU can't report a rate for 100%, hope 600 * the CPU is running at its nominal rate right now, 601 * and use that instead. 602 */ 603 if (sc->max_mhz <= 0) { 604 pc = cpu_get_pcpu(dev); 605 cpu_est_clockrate(pc->pc_cpuid, &rate); 606 sc->max_mhz = rate / 1000000; 607 } 608 } 609 memset(&sets[0], CPUFREQ_VAL_UNKNOWN, sizeof(*sets)); 610 sets[0].freq = sc->max_mhz; 611 sets[0].dev = NULL; 612 error = cpufreq_insert_abs(sc, sets, 1); 613 if (error) 614 goto out; 615 } 616 617 /* Create a combined list of absolute + relative levels. */ 618 TAILQ_FOREACH(set_arr, &rel_sets, link) 619 cpufreq_expand_set(sc, set_arr); 620 621 /* If the caller doesn't have enough space, return the actual count. */ 622 if (sc->all_count > *count) { 623 *count = sc->all_count; 624 error = E2BIG; 625 goto out; 626 } 627 628 /* Finally, output the list of levels. */ 629 i = 0; 630 TAILQ_FOREACH(lev, &sc->all_levels, link) { 631 632 /* Skip levels that have a frequency that is too low. */ 633 if (lev->total_set.freq < cf_lowest_freq) { 634 sc->all_count--; 635 continue; 636 } 637 638 levels[i] = *lev; 639 i++; 640 } 641 *count = sc->all_count; 642 error = 0; 643 644 out: 645 /* Clear all levels since we regenerate them each time. */ 646 while ((lev = TAILQ_FIRST(&sc->all_levels)) != NULL) { 647 TAILQ_REMOVE(&sc->all_levels, lev, link); 648 free(lev, M_TEMP); 649 } 650 sc->all_count = 0; 651 652 CF_MTX_UNLOCK(&sc->lock); 653 while ((set_arr = TAILQ_FIRST(&rel_sets)) != NULL) { 654 TAILQ_REMOVE(&rel_sets, set_arr, link); 655 free(set_arr, M_TEMP); 656 } 657 free(devs, M_TEMP); 658 free(sets, M_TEMP); 659 return (error); 660 } 661 662 /* 663 * Create levels for an array of absolute settings and insert them in 664 * sorted order in the specified list. 665 */ 666 static int 667 cpufreq_insert_abs(struct cpufreq_softc *sc, struct cf_setting *sets, 668 int count) 669 { 670 struct cf_level_lst *list; 671 struct cf_level *level, *search; 672 int i; 673 674 CF_MTX_ASSERT(&sc->lock); 675 676 list = &sc->all_levels; 677 for (i = 0; i < count; i++) { 678 level = malloc(sizeof(*level), M_TEMP, M_NOWAIT | M_ZERO); 679 if (level == NULL) 680 return (ENOMEM); 681 level->abs_set = sets[i]; 682 level->total_set = sets[i]; 683 level->total_set.dev = NULL; 684 sc->all_count++; 685 686 if (TAILQ_EMPTY(list)) { 687 CF_DEBUG("adding abs setting %d at head\n", 688 sets[i].freq); 689 TAILQ_INSERT_HEAD(list, level, link); 690 continue; 691 } 692 693 TAILQ_FOREACH_REVERSE(search, list, cf_level_lst, link) { 694 if (sets[i].freq <= search->total_set.freq) { 695 CF_DEBUG("adding abs setting %d after %d\n", 696 sets[i].freq, search->total_set.freq); 697 TAILQ_INSERT_AFTER(list, search, level, link); 698 break; 699 } 700 } 701 } 702 return (0); 703 } 704 705 /* 706 * Expand a group of relative settings, creating derived levels from them. 707 */ 708 static int 709 cpufreq_expand_set(struct cpufreq_softc *sc, struct cf_setting_array *set_arr) 710 { 711 struct cf_level *fill, *search; 712 struct cf_setting *set; 713 int i; 714 715 CF_MTX_ASSERT(&sc->lock); 716 717 /* 718 * Walk the set of all existing levels in reverse. This is so we 719 * create derived states from the lowest absolute settings first 720 * and discard duplicates created from higher absolute settings. 721 * For instance, a level of 50 Mhz derived from 100 Mhz + 50% is 722 * preferable to 200 Mhz + 25% because absolute settings are more 723 * efficient since they often change the voltage as well. 724 */ 725 TAILQ_FOREACH_REVERSE(search, &sc->all_levels, cf_level_lst, link) { 726 /* Add each setting to the level, duplicating if necessary. */ 727 for (i = 0; i < set_arr->count; i++) { 728 set = &set_arr->sets[i]; 729 730 /* 731 * If this setting is less than 100%, split the level 732 * into two and add this setting to the new level. 733 */ 734 fill = search; 735 if (set->freq < 10000) { 736 fill = cpufreq_dup_set(sc, search, set); 737 738 /* 739 * The new level was a duplicate of an existing 740 * level or its absolute setting is too high 741 * so we freed it. For example, we discard a 742 * derived level of 1000 MHz/25% if a level 743 * of 500 MHz/100% already exists. 744 */ 745 if (fill == NULL) 746 break; 747 } 748 749 /* Add this setting to the existing or new level. */ 750 KASSERT(fill->rel_count < MAX_SETTINGS, 751 ("cpufreq: too many relative drivers (%d)", 752 MAX_SETTINGS)); 753 fill->rel_set[fill->rel_count] = *set; 754 fill->rel_count++; 755 CF_DEBUG( 756 "expand set added rel setting %d%% to %d level\n", 757 set->freq / 100, fill->total_set.freq); 758 } 759 } 760 761 return (0); 762 } 763 764 static struct cf_level * 765 cpufreq_dup_set(struct cpufreq_softc *sc, struct cf_level *dup, 766 struct cf_setting *set) 767 { 768 struct cf_level_lst *list; 769 struct cf_level *fill, *itr; 770 struct cf_setting *fill_set, *itr_set; 771 int i; 772 773 CF_MTX_ASSERT(&sc->lock); 774 775 /* 776 * Create a new level, copy it from the old one, and update the 777 * total frequency and power by the percentage specified in the 778 * relative setting. 779 */ 780 fill = malloc(sizeof(*fill), M_TEMP, M_NOWAIT); 781 if (fill == NULL) 782 return (NULL); 783 *fill = *dup; 784 fill_set = &fill->total_set; 785 fill_set->freq = 786 ((uint64_t)fill_set->freq * set->freq) / 10000; 787 if (fill_set->power != CPUFREQ_VAL_UNKNOWN) { 788 fill_set->power = ((uint64_t)fill_set->power * set->freq) 789 / 10000; 790 } 791 if (set->lat != CPUFREQ_VAL_UNKNOWN) { 792 if (fill_set->lat != CPUFREQ_VAL_UNKNOWN) 793 fill_set->lat += set->lat; 794 else 795 fill_set->lat = set->lat; 796 } 797 CF_DEBUG("dup set considering derived setting %d\n", fill_set->freq); 798 799 /* 800 * If we copied an old level that we already modified (say, at 100%), 801 * we need to remove that setting before adding this one. Since we 802 * process each setting array in order, we know any settings for this 803 * driver will be found at the end. 804 */ 805 for (i = fill->rel_count; i != 0; i--) { 806 if (fill->rel_set[i - 1].dev != set->dev) 807 break; 808 CF_DEBUG("removed last relative driver: %s\n", 809 device_get_nameunit(set->dev)); 810 fill->rel_count--; 811 } 812 813 /* 814 * Insert the new level in sorted order. If it is a duplicate of an 815 * existing level (1) or has an absolute setting higher than the 816 * existing level (2), do not add it. We can do this since any such 817 * level is guaranteed use less power. For example (1), a level with 818 * one absolute setting of 800 Mhz uses less power than one composed 819 * of an absolute setting of 1600 Mhz and a relative setting at 50%. 820 * Also for example (2), a level of 800 Mhz/75% is preferable to 821 * 1600 Mhz/25% even though the latter has a lower total frequency. 822 */ 823 list = &sc->all_levels; 824 KASSERT(!TAILQ_EMPTY(list), ("all levels list empty in dup set")); 825 TAILQ_FOREACH_REVERSE(itr, list, cf_level_lst, link) { 826 itr_set = &itr->total_set; 827 if (CPUFREQ_CMP(fill_set->freq, itr_set->freq)) { 828 CF_DEBUG("dup set rejecting %d (dupe)\n", 829 fill_set->freq); 830 itr = NULL; 831 break; 832 } else if (fill_set->freq < itr_set->freq) { 833 if (fill->abs_set.freq <= itr->abs_set.freq) { 834 CF_DEBUG( 835 "dup done, inserting new level %d after %d\n", 836 fill_set->freq, itr_set->freq); 837 TAILQ_INSERT_AFTER(list, itr, fill, link); 838 sc->all_count++; 839 } else { 840 CF_DEBUG("dup set rejecting %d (abs too big)\n", 841 fill_set->freq); 842 itr = NULL; 843 } 844 break; 845 } 846 } 847 848 /* We didn't find a good place for this new level so free it. */ 849 if (itr == NULL) { 850 CF_DEBUG("dup set freeing new level %d (not optimal)\n", 851 fill_set->freq); 852 free(fill, M_TEMP); 853 fill = NULL; 854 } 855 856 return (fill); 857 } 858 859 static int 860 cpufreq_curr_sysctl(SYSCTL_HANDLER_ARGS) 861 { 862 struct cpufreq_softc *sc; 863 struct cf_level *levels; 864 int best, count, diff, bdiff, devcount, error, freq, i, n; 865 device_t *devs; 866 867 devs = NULL; 868 sc = oidp->oid_arg1; 869 levels = sc->levels_buf; 870 871 error = CPUFREQ_GET(sc->dev, &levels[0]); 872 if (error) 873 goto out; 874 freq = levels[0].total_set.freq; 875 error = sysctl_handle_int(oidp, &freq, 0, req); 876 if (error != 0 || req->newptr == NULL) 877 goto out; 878 879 /* 880 * While we only call cpufreq_get() on one device (assuming all 881 * CPUs have equal levels), we call cpufreq_set() on all CPUs. 882 * This is needed for some MP systems. 883 */ 884 error = devclass_get_devices(cpufreq_dc, &devs, &devcount); 885 if (error) 886 goto out; 887 for (n = 0; n < devcount; n++) { 888 count = CF_MAX_LEVELS; 889 error = CPUFREQ_LEVELS(devs[n], levels, &count); 890 if (error) { 891 if (error == E2BIG) 892 printf( 893 "cpufreq: need to increase CF_MAX_LEVELS\n"); 894 break; 895 } 896 best = 0; 897 bdiff = 1 << 30; 898 for (i = 0; i < count; i++) { 899 diff = abs(levels[i].total_set.freq - freq); 900 if (diff < bdiff) { 901 bdiff = diff; 902 best = i; 903 } 904 } 905 error = CPUFREQ_SET(devs[n], &levels[best], CPUFREQ_PRIO_USER); 906 } 907 908 out: 909 if (devs) 910 free(devs, M_TEMP); 911 return (error); 912 } 913 914 static int 915 cpufreq_levels_sysctl(SYSCTL_HANDLER_ARGS) 916 { 917 struct cpufreq_softc *sc; 918 struct cf_level *levels; 919 struct cf_setting *set; 920 struct sbuf sb; 921 int count, error, i; 922 923 sc = oidp->oid_arg1; 924 sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND); 925 926 /* Get settings from the device and generate the output string. */ 927 count = CF_MAX_LEVELS; 928 levels = sc->levels_buf; 929 if (levels == NULL) { 930 sbuf_delete(&sb); 931 return (ENOMEM); 932 } 933 error = CPUFREQ_LEVELS(sc->dev, levels, &count); 934 if (error) { 935 if (error == E2BIG) 936 printf("cpufreq: need to increase CF_MAX_LEVELS\n"); 937 goto out; 938 } 939 if (count) { 940 for (i = 0; i < count; i++) { 941 set = &levels[i].total_set; 942 sbuf_printf(&sb, "%d/%d ", set->freq, set->power); 943 } 944 } else 945 sbuf_cpy(&sb, "0"); 946 sbuf_trim(&sb); 947 sbuf_finish(&sb); 948 error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req); 949 950 out: 951 sbuf_delete(&sb); 952 return (error); 953 } 954 955 static int 956 cpufreq_settings_sysctl(SYSCTL_HANDLER_ARGS) 957 { 958 device_t dev; 959 struct cf_setting *sets; 960 struct sbuf sb; 961 int error, i, set_count; 962 963 dev = oidp->oid_arg1; 964 sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND); 965 966 /* Get settings from the device and generate the output string. */ 967 set_count = MAX_SETTINGS; 968 sets = malloc(set_count * sizeof(*sets), M_TEMP, M_NOWAIT); 969 if (sets == NULL) { 970 sbuf_delete(&sb); 971 return (ENOMEM); 972 } 973 error = CPUFREQ_DRV_SETTINGS(dev, sets, &set_count); 974 if (error) 975 goto out; 976 if (set_count) { 977 for (i = 0; i < set_count; i++) 978 sbuf_printf(&sb, "%d/%d ", sets[i].freq, sets[i].power); 979 } else 980 sbuf_cpy(&sb, "0"); 981 sbuf_trim(&sb); 982 sbuf_finish(&sb); 983 error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req); 984 985 out: 986 free(sets, M_TEMP); 987 sbuf_delete(&sb); 988 return (error); 989 } 990 991 int 992 cpufreq_register(device_t dev) 993 { 994 struct cpufreq_softc *sc; 995 device_t cf_dev, cpu_dev; 996 997 /* Add a sysctl to get each driver's settings separately. */ 998 SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev), 999 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 1000 OID_AUTO, "freq_settings", CTLTYPE_STRING | CTLFLAG_RD, dev, 0, 1001 cpufreq_settings_sysctl, "A", "CPU frequency driver settings"); 1002 1003 /* 1004 * Add only one cpufreq device to each CPU. Currently, all CPUs 1005 * must offer the same levels and be switched at the same time. 1006 */ 1007 cpu_dev = device_get_parent(dev); 1008 if ((cf_dev = device_find_child(cpu_dev, "cpufreq", -1))) { 1009 sc = device_get_softc(cf_dev); 1010 sc->max_mhz = CPUFREQ_VAL_UNKNOWN; 1011 return (0); 1012 } 1013 1014 /* Add the child device and possibly sysctls. */ 1015 cf_dev = BUS_ADD_CHILD(cpu_dev, 0, "cpufreq", -1); 1016 if (cf_dev == NULL) 1017 return (ENOMEM); 1018 device_quiet(cf_dev); 1019 1020 return (device_probe_and_attach(cf_dev)); 1021 } 1022 1023 int 1024 cpufreq_unregister(device_t dev) 1025 { 1026 device_t cf_dev, *devs; 1027 int cfcount, devcount, error, i, type; 1028 1029 /* 1030 * If this is the last cpufreq child device, remove the control 1031 * device as well. We identify cpufreq children by calling a method 1032 * they support. 1033 */ 1034 error = device_get_children(device_get_parent(dev), &devs, &devcount); 1035 if (error) 1036 return (error); 1037 cf_dev = device_find_child(device_get_parent(dev), "cpufreq", -1); 1038 if (cf_dev == NULL) { 1039 device_printf(dev, 1040 "warning: cpufreq_unregister called with no cpufreq device active\n"); 1041 free(devs, M_TEMP); 1042 return (0); 1043 } 1044 cfcount = 0; 1045 for (i = 0; i < devcount; i++) { 1046 if (!device_is_attached(devs[i])) 1047 continue; 1048 if (CPUFREQ_DRV_TYPE(devs[i], &type) == 0) 1049 cfcount++; 1050 } 1051 if (cfcount <= 1) 1052 device_delete_child(device_get_parent(cf_dev), cf_dev); 1053 free(devs, M_TEMP); 1054 1055 return (0); 1056 } 1057 1058 int 1059 cpufreq_settings_changed(device_t dev) 1060 { 1061 1062 EVENTHANDLER_INVOKE(cpufreq_levels_changed, 1063 device_get_unit(device_get_parent(dev))); 1064 return (0); 1065 } 1066