acpi_cpu_pstate.c revision 1.16
1 /* $NetBSD: acpi_cpu_pstate.c,v 1.16 2010/08/13 18:44:24 jruoho Exp $ */ 2 3 /*- 4 * Copyright (c) 2010 Jukka Ruohonen <jruohonen (at) iki.fi> 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 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: acpi_cpu_pstate.c,v 1.16 2010/08/13 18:44:24 jruoho Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/evcnt.h> 34 #include <sys/kmem.h> 35 #include <sys/once.h> 36 37 #include <dev/acpi/acpireg.h> 38 #include <dev/acpi/acpivar.h> 39 #include <dev/acpi/acpi_cpu.h> 40 41 #define _COMPONENT ACPI_BUS_COMPONENT 42 ACPI_MODULE_NAME ("acpi_cpu_pstate") 43 44 static void acpicpu_pstate_attach_print(struct acpicpu_softc *); 45 static void acpicpu_pstate_attach_evcnt(struct acpicpu_softc *); 46 static void acpicpu_pstate_detach_evcnt(struct acpicpu_softc *); 47 static ACPI_STATUS acpicpu_pstate_pss(struct acpicpu_softc *sc); 48 static ACPI_STATUS acpicpu_pstate_pss_add(struct acpicpu_pstate *, 49 ACPI_OBJECT *); 50 static ACPI_STATUS acpicpu_pstate_pct(struct acpicpu_softc *); 51 static int acpicpu_pstate_max(struct acpicpu_softc *); 52 static void acpicpu_pstate_change(struct acpicpu_softc *); 53 static void acpicpu_pstate_bios(void); 54 55 void 56 acpicpu_pstate_attach(device_t self) 57 { 58 struct acpicpu_softc *sc = device_private(self); 59 const char *str; 60 ACPI_STATUS rv; 61 62 /* 63 * Three control methods are mandatory 64 * for P-states; _PSS, _PCT, and _PPC. 65 */ 66 rv = acpicpu_pstate_pss(sc); 67 68 if (ACPI_FAILURE(rv)) { 69 str = "_PSS"; 70 goto fail; 71 } 72 73 rv = acpicpu_pstate_pct(sc); 74 75 if (ACPI_FAILURE(rv)) { 76 str = "_PCT"; 77 goto fail; 78 } 79 80 rv = acpicpu_pstate_max(sc); 81 82 if (rv != 0) { 83 str = "_PPC"; 84 goto fail; 85 } 86 87 sc->sc_flags |= ACPICPU_FLAG_P; 88 sc->sc_pstate_current = sc->sc_pstate[0].ps_freq; 89 90 acpicpu_pstate_bios(); 91 acpicpu_pstate_attach_evcnt(sc); 92 acpicpu_pstate_attach_print(sc); 93 94 return; 95 96 fail: 97 switch (rv) { 98 99 case AE_NOT_FOUND: 100 return; 101 102 case AE_SUPPORT: 103 aprint_verbose_dev(sc->sc_dev, "P-states not supported\n"); 104 return; 105 106 default: 107 aprint_error_dev(sc->sc_dev, "failed to evaluate " 108 "%s: %s\n", str, AcpiFormatException(rv)); 109 } 110 } 111 112 static void 113 acpicpu_pstate_attach_print(struct acpicpu_softc *sc) 114 { 115 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 116 struct acpicpu_pstate *ps; 117 static bool once = false; 118 const char *str; 119 uint32_t i; 120 121 if (once != false) 122 return; 123 124 str = (method != ACPI_ADR_SPACE_SYSTEM_IO) ? "FFH" : "I/O"; 125 126 for (i = 0; i < sc->sc_pstate_count; i++) { 127 128 ps = &sc->sc_pstate[i]; 129 130 if (ps->ps_freq == 0) 131 continue; 132 133 aprint_debug_dev(sc->sc_dev, "P%d: %3s, " 134 "lat %3u us, pow %5u mW, %4u MHz\n", i, str, 135 ps->ps_latency, ps->ps_power, ps->ps_freq); 136 } 137 138 once = true; 139 } 140 141 static void 142 acpicpu_pstate_attach_evcnt(struct acpicpu_softc *sc) 143 { 144 struct acpicpu_pstate *ps; 145 uint32_t i; 146 147 for (i = 0; i < sc->sc_pstate_count; i++) { 148 149 ps = &sc->sc_pstate[i]; 150 151 if (ps->ps_freq == 0) 152 continue; 153 154 (void)snprintf(ps->ps_name, sizeof(ps->ps_name), 155 "P%u (%u MHz)", i, ps->ps_freq); 156 157 evcnt_attach_dynamic(&ps->ps_evcnt, EVCNT_TYPE_MISC, 158 NULL, device_xname(sc->sc_dev), ps->ps_name); 159 } 160 } 161 162 int 163 acpicpu_pstate_detach(device_t self) 164 { 165 struct acpicpu_softc *sc = device_private(self); 166 static ONCE_DECL(once_detach); 167 size_t size; 168 int rv; 169 170 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) 171 return 0; 172 173 rv = RUN_ONCE(&once_detach, acpicpu_md_pstate_stop); 174 175 if (rv != 0) 176 return rv; 177 178 size = sc->sc_pstate_count * sizeof(*sc->sc_pstate); 179 180 if (sc->sc_pstate != NULL) 181 kmem_free(sc->sc_pstate, size); 182 183 sc->sc_flags &= ~ACPICPU_FLAG_P; 184 acpicpu_pstate_detach_evcnt(sc); 185 186 return 0; 187 } 188 189 static void 190 acpicpu_pstate_detach_evcnt(struct acpicpu_softc *sc) 191 { 192 struct acpicpu_pstate *ps; 193 uint32_t i; 194 195 for (i = 0; i < sc->sc_pstate_count; i++) { 196 197 ps = &sc->sc_pstate[i]; 198 199 if (ps->ps_freq != 0) 200 evcnt_detach(&ps->ps_evcnt); 201 } 202 } 203 204 int 205 acpicpu_pstate_start(device_t self) 206 { 207 struct acpicpu_softc *sc = device_private(self); 208 static ONCE_DECL(once_start); 209 210 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) 211 return 0; 212 213 return RUN_ONCE(&once_start, acpicpu_md_pstate_start); 214 } 215 216 bool 217 acpicpu_pstate_suspend(device_t self) 218 { 219 220 return true; 221 } 222 223 bool 224 acpicpu_pstate_resume(device_t self) 225 { 226 static const ACPI_OSD_EXEC_CALLBACK func = acpicpu_pstate_callback; 227 struct acpicpu_softc *sc = device_private(self); 228 229 (void)AcpiOsExecute(OSL_NOTIFY_HANDLER, func, sc->sc_dev); 230 231 return true; 232 } 233 234 void 235 acpicpu_pstate_callback(void *aux) 236 { 237 struct acpicpu_softc *sc; 238 device_t self = aux; 239 uint32_t old, new; 240 241 sc = device_private(self); 242 243 mutex_enter(&sc->sc_mtx); 244 old = sc->sc_pstate_max; 245 acpicpu_pstate_change(sc); 246 new = sc->sc_pstate_max; 247 mutex_exit(&sc->sc_mtx); 248 249 if (old != new) { 250 251 aprint_debug_dev(sc->sc_dev, "maximum frequency " 252 "changed from P%u (%u MHz) to P%u (%u MHz)\n", 253 old, sc->sc_pstate[old].ps_freq, new, 254 sc->sc_pstate[sc->sc_pstate_max].ps_freq); 255 #if 0 256 /* 257 * If the maximum changed, proactively 258 * raise or lower the target frequency. 259 */ 260 acpicpu_pstate_set(sc, sc->sc_pstate[new].ps_freq); 261 262 #endif 263 } 264 } 265 266 ACPI_STATUS 267 acpicpu_pstate_pss(struct acpicpu_softc *sc) 268 { 269 struct acpicpu_pstate *ps; 270 ACPI_OBJECT *obj; 271 ACPI_BUFFER buf; 272 ACPI_STATUS rv; 273 uint32_t count; 274 uint32_t i, j; 275 276 rv = acpi_eval_struct(sc->sc_node->ad_handle, "_PSS", &buf); 277 278 if (ACPI_FAILURE(rv)) 279 return rv; 280 281 obj = buf.Pointer; 282 283 if (obj->Type != ACPI_TYPE_PACKAGE) { 284 rv = AE_TYPE; 285 goto out; 286 } 287 288 sc->sc_pstate_count = obj->Package.Count; 289 290 if (sc->sc_pstate_count == 0) { 291 rv = AE_NOT_EXIST; 292 goto out; 293 } 294 295 if (sc->sc_pstate_count > ACPICPU_P_STATE_MAX) { 296 rv = AE_LIMIT; 297 goto out; 298 } 299 300 sc->sc_pstate = kmem_zalloc(sc->sc_pstate_count * 301 sizeof(struct acpicpu_pstate), KM_SLEEP); 302 303 if (sc->sc_pstate == NULL) { 304 rv = AE_NO_MEMORY; 305 goto out; 306 } 307 308 for (count = i = 0; i < sc->sc_pstate_count; i++) { 309 310 ps = &sc->sc_pstate[i]; 311 rv = acpicpu_pstate_pss_add(ps, &obj->Package.Elements[i]); 312 313 if (ACPI_FAILURE(rv)) { 314 ps->ps_freq = 0; 315 continue; 316 } 317 318 for (j = 0; j < i; j++) { 319 320 if (ps->ps_freq >= sc->sc_pstate[j].ps_freq) { 321 ps->ps_freq = 0; 322 break; 323 } 324 } 325 326 if (ps->ps_freq != 0) 327 count++; 328 } 329 330 rv = (count != 0) ? AE_OK : AE_NOT_EXIST; 331 332 out: 333 if (buf.Pointer != NULL) 334 ACPI_FREE(buf.Pointer); 335 336 return rv; 337 } 338 339 static ACPI_STATUS 340 acpicpu_pstate_pss_add(struct acpicpu_pstate *ps, ACPI_OBJECT *obj) 341 { 342 ACPI_OBJECT *elm; 343 uint32_t val[6]; 344 uint32_t *p; 345 int i; 346 347 if (obj->Type != ACPI_TYPE_PACKAGE) 348 return AE_TYPE; 349 350 if (obj->Package.Count != 6) 351 return AE_BAD_DATA; 352 353 elm = obj->Package.Elements; 354 355 for (i = 0; i < 6; i++) { 356 357 if (elm[i].Type != ACPI_TYPE_INTEGER) 358 return AE_TYPE; 359 360 if (elm[i].Integer.Value > UINT32_MAX) 361 return AE_AML_NUMERIC_OVERFLOW; 362 363 val[i] = elm[i].Integer.Value; 364 } 365 366 CTASSERT(sizeof(val) == sizeof(struct acpicpu_pstate) - 367 offsetof(struct acpicpu_pstate, ps_freq)); 368 369 p = &ps->ps_freq; 370 371 for (i = 0; i < 6; i++, p++) 372 *p = val[i]; 373 374 if (ps->ps_freq == 0 || ps->ps_freq > 9999) 375 return AE_BAD_DECIMAL_CONSTANT; 376 377 /* 378 * The latency is typically around 10 usec 379 * on Intel CPUs. Use that as the minimum. 380 */ 381 if (ps->ps_latency < 10) 382 ps->ps_latency = 10; 383 384 return AE_OK; 385 } 386 387 ACPI_STATUS 388 acpicpu_pstate_pct(struct acpicpu_softc *sc) 389 { 390 static const size_t size = sizeof(struct acpicpu_reg); 391 struct acpicpu_reg *reg[2]; 392 ACPI_OBJECT *elm, *obj; 393 ACPI_BUFFER buf; 394 ACPI_STATUS rv; 395 uint8_t width; 396 int i; 397 398 rv = acpi_eval_struct(sc->sc_node->ad_handle, "_PCT", &buf); 399 400 if (ACPI_FAILURE(rv)) 401 return rv; 402 403 obj = buf.Pointer; 404 405 if (obj->Type != ACPI_TYPE_PACKAGE) { 406 rv = AE_TYPE; 407 goto out; 408 } 409 410 if (obj->Package.Count != 2) { 411 rv = AE_LIMIT; 412 goto out; 413 } 414 415 for (i = 0; i < 2; i++) { 416 417 elm = &obj->Package.Elements[i]; 418 419 if (elm->Type != ACPI_TYPE_BUFFER) { 420 rv = AE_TYPE; 421 goto out; 422 } 423 424 if (size > elm->Buffer.Length) { 425 rv = AE_AML_BAD_RESOURCE_LENGTH; 426 goto out; 427 } 428 429 reg[i] = (struct acpicpu_reg *)elm->Buffer.Pointer; 430 431 switch (reg[i]->reg_spaceid) { 432 433 case ACPI_ADR_SPACE_SYSTEM_IO: 434 435 if (reg[i]->reg_addr == 0) { 436 rv = AE_AML_ILLEGAL_ADDRESS; 437 goto out; 438 } 439 440 width = reg[i]->reg_bitwidth; 441 442 if (width + reg[i]->reg_bitoffset > 32) { 443 rv = AE_AML_BAD_RESOURCE_VALUE; 444 goto out; 445 } 446 447 if (width != 8 && width != 16 && width != 32) { 448 rv = AE_AML_BAD_RESOURCE_VALUE; 449 goto out; 450 } 451 452 break; 453 454 case ACPI_ADR_SPACE_FIXED_HARDWARE: 455 456 if ((sc->sc_flags & ACPICPU_FLAG_P_FFH) == 0) { 457 rv = AE_SUPPORT; 458 goto out; 459 } 460 461 break; 462 463 default: 464 rv = AE_AML_INVALID_SPACE_ID; 465 goto out; 466 } 467 } 468 469 if (reg[0]->reg_spaceid != reg[1]->reg_spaceid) { 470 rv = AE_AML_INVALID_SPACE_ID; 471 goto out; 472 } 473 474 (void)memcpy(&sc->sc_pstate_control, reg[0], size); 475 (void)memcpy(&sc->sc_pstate_status, reg[1], size); 476 477 out: 478 if (buf.Pointer != NULL) 479 ACPI_FREE(buf.Pointer); 480 481 return rv; 482 } 483 484 static int 485 acpicpu_pstate_max(struct acpicpu_softc *sc) 486 { 487 ACPI_INTEGER val; 488 ACPI_STATUS rv; 489 490 /* 491 * Evaluate the currently highest P-state that can be used. 492 * If available, we can use either this state or any lower 493 * power (i.e. higher numbered) state from the _PSS object. 494 */ 495 rv = acpi_eval_integer(sc->sc_node->ad_handle, "_PPC", &val); 496 497 sc->sc_pstate_max = 0; 498 499 if (ACPI_FAILURE(rv)) 500 return 1; 501 502 if (val > sc->sc_pstate_count - 1) 503 return 1; 504 505 if (sc->sc_pstate[val].ps_freq == 0) 506 return 1; 507 508 sc->sc_pstate_max = val; 509 510 return 0; 511 } 512 513 static void 514 acpicpu_pstate_change(struct acpicpu_softc *sc) 515 { 516 ACPI_OBJECT_LIST arg; 517 ACPI_OBJECT obj[2]; 518 519 arg.Count = 2; 520 arg.Pointer = obj; 521 522 obj[0].Type = ACPI_TYPE_INTEGER; 523 obj[1].Type = ACPI_TYPE_INTEGER; 524 525 obj[0].Integer.Value = ACPICPU_P_NOTIFY; 526 obj[1].Integer.Value = acpicpu_pstate_max(sc); 527 528 (void)AcpiEvaluateObject(sc->sc_node->ad_handle, "_OST", &arg, NULL); 529 } 530 531 static void 532 acpicpu_pstate_bios(void) 533 { 534 const uint8_t val = AcpiGbl_FADT.PstateControl; 535 const uint32_t addr = AcpiGbl_FADT.SmiCommand; 536 537 if (addr == 0) 538 return; 539 540 (void)AcpiOsWritePort(addr, val, 8); 541 } 542 543 int 544 acpicpu_pstate_get(struct acpicpu_softc *sc, uint32_t *freq) 545 { 546 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 547 struct acpicpu_pstate *ps = NULL; 548 uint32_t i, val = 0; 549 uint64_t addr; 550 uint8_t width; 551 int rv; 552 553 if (sc->sc_cold != false) { 554 rv = EBUSY; 555 goto fail; 556 } 557 558 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) { 559 rv = ENODEV; 560 goto fail; 561 } 562 563 mutex_enter(&sc->sc_mtx); 564 565 if (sc->sc_pstate_current != ACPICPU_P_STATE_UNKNOWN) { 566 *freq = sc->sc_pstate_current; 567 mutex_exit(&sc->sc_mtx); 568 return 0; 569 } 570 571 mutex_exit(&sc->sc_mtx); 572 573 switch (method) { 574 575 case ACPI_ADR_SPACE_FIXED_HARDWARE: 576 577 rv = acpicpu_md_pstate_get(sc, freq); 578 579 if (rv != 0) 580 goto fail; 581 582 break; 583 584 case ACPI_ADR_SPACE_SYSTEM_IO: 585 586 addr = sc->sc_pstate_status.reg_addr; 587 width = sc->sc_pstate_status.reg_bitwidth; 588 589 (void)AcpiOsReadPort(addr, &val, width); 590 591 if (val == 0) { 592 rv = EIO; 593 goto fail; 594 } 595 596 for (i = 0; i < sc->sc_pstate_count; i++) { 597 598 if (sc->sc_pstate[i].ps_freq == 0) 599 continue; 600 601 if (val == sc->sc_pstate[i].ps_status) { 602 ps = &sc->sc_pstate[i]; 603 break; 604 } 605 } 606 607 if (__predict_false(ps == NULL)) { 608 rv = EIO; 609 goto fail; 610 } 611 612 *freq = ps->ps_freq; 613 break; 614 615 default: 616 rv = ENOTTY; 617 goto fail; 618 } 619 620 mutex_enter(&sc->sc_mtx); 621 sc->sc_pstate_current = *freq; 622 mutex_exit(&sc->sc_mtx); 623 624 return 0; 625 626 fail: 627 aprint_error_dev(sc->sc_dev, "failed " 628 "to get frequency (err %d)\n", rv); 629 630 mutex_enter(&sc->sc_mtx); 631 *freq = sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN; 632 mutex_exit(&sc->sc_mtx); 633 634 return rv; 635 } 636 637 int 638 acpicpu_pstate_set(struct acpicpu_softc *sc, uint32_t freq) 639 { 640 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 641 struct acpicpu_pstate *ps = NULL; 642 uint32_t i, val; 643 uint64_t addr; 644 uint8_t width; 645 int rv; 646 647 if (sc->sc_cold != false) { 648 rv = EBUSY; 649 goto fail; 650 } 651 652 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) { 653 rv = ENODEV; 654 goto fail; 655 } 656 657 mutex_enter(&sc->sc_mtx); 658 659 for (i = sc->sc_pstate_max; i < sc->sc_pstate_count; i++) { 660 661 if (sc->sc_pstate[i].ps_freq == 0) 662 continue; 663 664 if (sc->sc_pstate[i].ps_freq == freq) { 665 ps = &sc->sc_pstate[i]; 666 break; 667 } 668 } 669 670 mutex_exit(&sc->sc_mtx); 671 672 if (__predict_false(ps == NULL)) { 673 rv = EINVAL; 674 goto fail; 675 } 676 677 switch (method) { 678 679 case ACPI_ADR_SPACE_FIXED_HARDWARE: 680 681 rv = acpicpu_md_pstate_set(ps); 682 683 if (rv != 0) 684 goto fail; 685 686 break; 687 688 case ACPI_ADR_SPACE_SYSTEM_IO: 689 690 addr = sc->sc_pstate_control.reg_addr; 691 width = sc->sc_pstate_control.reg_bitwidth; 692 693 (void)AcpiOsWritePort(addr, ps->ps_control, width); 694 695 addr = sc->sc_pstate_status.reg_addr; 696 width = sc->sc_pstate_status.reg_bitwidth; 697 698 /* 699 * Some systems take longer to respond 700 * than the reported worst-case latency. 701 */ 702 for (i = val = 0; i < ACPICPU_P_STATE_RETRY; i++) { 703 704 (void)AcpiOsReadPort(addr, &val, width); 705 706 if (val == ps->ps_status) 707 break; 708 709 DELAY(ps->ps_latency); 710 } 711 712 if (i == ACPICPU_P_STATE_RETRY) { 713 rv = EAGAIN; 714 goto fail; 715 } 716 717 break; 718 719 default: 720 rv = ENOTTY; 721 goto fail; 722 } 723 724 mutex_enter(&sc->sc_mtx); 725 ps->ps_evcnt.ev_count++; 726 sc->sc_pstate_current = freq; 727 mutex_exit(&sc->sc_mtx); 728 729 return 0; 730 731 fail: 732 aprint_error_dev(sc->sc_dev, "failed to set " 733 "frequency to %u (err %d)\n", freq, rv); 734 735 mutex_enter(&sc->sc_mtx); 736 sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN; 737 mutex_exit(&sc->sc_mtx); 738 739 return rv; 740 } 741
Indexes created Tue Sep 30 20:09:53 GMT 2025