acpi_cpu_pstate.c revision 1.17
1 /* $NetBSD: acpi_cpu_pstate.c,v 1.17 2010/08/13 19:48:25 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 1.17 2010/08/13 19:48:25 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 p = &ps->ps_freq; 367 368 for (i = 0; i < 6; i++, p++) 369 *p = val[i]; 370 371 if (ps->ps_freq == 0 || ps->ps_freq > 9999) 372 return AE_BAD_DECIMAL_CONSTANT; 373 374 /* 375 * The latency is typically around 10 usec 376 * on Intel CPUs. Use that as the minimum. 377 */ 378 if (ps->ps_latency < 10) 379 ps->ps_latency = 10; 380 381 return AE_OK; 382 } 383 384 ACPI_STATUS 385 acpicpu_pstate_pct(struct acpicpu_softc *sc) 386 { 387 static const size_t size = sizeof(struct acpicpu_reg); 388 struct acpicpu_reg *reg[2]; 389 ACPI_OBJECT *elm, *obj; 390 ACPI_BUFFER buf; 391 ACPI_STATUS rv; 392 uint8_t width; 393 int i; 394 395 rv = acpi_eval_struct(sc->sc_node->ad_handle, "_PCT", &buf); 396 397 if (ACPI_FAILURE(rv)) 398 return rv; 399 400 obj = buf.Pointer; 401 402 if (obj->Type != ACPI_TYPE_PACKAGE) { 403 rv = AE_TYPE; 404 goto out; 405 } 406 407 if (obj->Package.Count != 2) { 408 rv = AE_LIMIT; 409 goto out; 410 } 411 412 for (i = 0; i < 2; i++) { 413 414 elm = &obj->Package.Elements[i]; 415 416 if (elm->Type != ACPI_TYPE_BUFFER) { 417 rv = AE_TYPE; 418 goto out; 419 } 420 421 if (size > elm->Buffer.Length) { 422 rv = AE_AML_BAD_RESOURCE_LENGTH; 423 goto out; 424 } 425 426 reg[i] = (struct acpicpu_reg *)elm->Buffer.Pointer; 427 428 switch (reg[i]->reg_spaceid) { 429 430 case ACPI_ADR_SPACE_SYSTEM_IO: 431 432 if (reg[i]->reg_addr == 0) { 433 rv = AE_AML_ILLEGAL_ADDRESS; 434 goto out; 435 } 436 437 width = reg[i]->reg_bitwidth; 438 439 if (width + reg[i]->reg_bitoffset > 32) { 440 rv = AE_AML_BAD_RESOURCE_VALUE; 441 goto out; 442 } 443 444 if (width != 8 && width != 16 && width != 32) { 445 rv = AE_AML_BAD_RESOURCE_VALUE; 446 goto out; 447 } 448 449 break; 450 451 case ACPI_ADR_SPACE_FIXED_HARDWARE: 452 453 if ((sc->sc_flags & ACPICPU_FLAG_P_FFH) == 0) { 454 rv = AE_SUPPORT; 455 goto out; 456 } 457 458 break; 459 460 default: 461 rv = AE_AML_INVALID_SPACE_ID; 462 goto out; 463 } 464 } 465 466 if (reg[0]->reg_spaceid != reg[1]->reg_spaceid) { 467 rv = AE_AML_INVALID_SPACE_ID; 468 goto out; 469 } 470 471 (void)memcpy(&sc->sc_pstate_control, reg[0], size); 472 (void)memcpy(&sc->sc_pstate_status, reg[1], size); 473 474 out: 475 if (buf.Pointer != NULL) 476 ACPI_FREE(buf.Pointer); 477 478 return rv; 479 } 480 481 static int 482 acpicpu_pstate_max(struct acpicpu_softc *sc) 483 { 484 ACPI_INTEGER val; 485 ACPI_STATUS rv; 486 487 /* 488 * Evaluate the currently highest P-state that can be used. 489 * If available, we can use either this state or any lower 490 * power (i.e. higher numbered) state from the _PSS object. 491 */ 492 rv = acpi_eval_integer(sc->sc_node->ad_handle, "_PPC", &val); 493 494 sc->sc_pstate_max = 0; 495 496 if (ACPI_FAILURE(rv)) 497 return 1; 498 499 if (val > sc->sc_pstate_count - 1) 500 return 1; 501 502 if (sc->sc_pstate[val].ps_freq == 0) 503 return 1; 504 505 sc->sc_pstate_max = val; 506 507 return 0; 508 } 509 510 static void 511 acpicpu_pstate_change(struct acpicpu_softc *sc) 512 { 513 ACPI_OBJECT_LIST arg; 514 ACPI_OBJECT obj[2]; 515 516 arg.Count = 2; 517 arg.Pointer = obj; 518 519 obj[0].Type = ACPI_TYPE_INTEGER; 520 obj[1].Type = ACPI_TYPE_INTEGER; 521 522 obj[0].Integer.Value = ACPICPU_P_NOTIFY; 523 obj[1].Integer.Value = acpicpu_pstate_max(sc); 524 525 (void)AcpiEvaluateObject(sc->sc_node->ad_handle, "_OST", &arg, NULL); 526 } 527 528 static void 529 acpicpu_pstate_bios(void) 530 { 531 const uint8_t val = AcpiGbl_FADT.PstateControl; 532 const uint32_t addr = AcpiGbl_FADT.SmiCommand; 533 534 if (addr == 0) 535 return; 536 537 (void)AcpiOsWritePort(addr, val, 8); 538 } 539 540 int 541 acpicpu_pstate_get(struct acpicpu_softc *sc, uint32_t *freq) 542 { 543 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 544 struct acpicpu_pstate *ps = NULL; 545 uint32_t i, val = 0; 546 uint64_t addr; 547 uint8_t width; 548 int rv; 549 550 if (sc->sc_cold != false) { 551 rv = EBUSY; 552 goto fail; 553 } 554 555 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) { 556 rv = ENODEV; 557 goto fail; 558 } 559 560 mutex_enter(&sc->sc_mtx); 561 562 if (sc->sc_pstate_current != ACPICPU_P_STATE_UNKNOWN) { 563 *freq = sc->sc_pstate_current; 564 mutex_exit(&sc->sc_mtx); 565 return 0; 566 } 567 568 mutex_exit(&sc->sc_mtx); 569 570 switch (method) { 571 572 case ACPI_ADR_SPACE_FIXED_HARDWARE: 573 574 rv = acpicpu_md_pstate_get(sc, freq); 575 576 if (rv != 0) 577 goto fail; 578 579 break; 580 581 case ACPI_ADR_SPACE_SYSTEM_IO: 582 583 addr = sc->sc_pstate_status.reg_addr; 584 width = sc->sc_pstate_status.reg_bitwidth; 585 586 (void)AcpiOsReadPort(addr, &val, width); 587 588 if (val == 0) { 589 rv = EIO; 590 goto fail; 591 } 592 593 for (i = 0; i < sc->sc_pstate_count; i++) { 594 595 if (sc->sc_pstate[i].ps_freq == 0) 596 continue; 597 598 if (val == sc->sc_pstate[i].ps_status) { 599 ps = &sc->sc_pstate[i]; 600 break; 601 } 602 } 603 604 if (__predict_false(ps == NULL)) { 605 rv = EIO; 606 goto fail; 607 } 608 609 *freq = ps->ps_freq; 610 break; 611 612 default: 613 rv = ENOTTY; 614 goto fail; 615 } 616 617 mutex_enter(&sc->sc_mtx); 618 sc->sc_pstate_current = *freq; 619 mutex_exit(&sc->sc_mtx); 620 621 return 0; 622 623 fail: 624 aprint_error_dev(sc->sc_dev, "failed " 625 "to get frequency (err %d)\n", rv); 626 627 mutex_enter(&sc->sc_mtx); 628 *freq = sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN; 629 mutex_exit(&sc->sc_mtx); 630 631 return rv; 632 } 633 634 int 635 acpicpu_pstate_set(struct acpicpu_softc *sc, uint32_t freq) 636 { 637 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 638 struct acpicpu_pstate *ps = NULL; 639 uint32_t i, val; 640 uint64_t addr; 641 uint8_t width; 642 int rv; 643 644 if (sc->sc_cold != false) { 645 rv = EBUSY; 646 goto fail; 647 } 648 649 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) { 650 rv = ENODEV; 651 goto fail; 652 } 653 654 mutex_enter(&sc->sc_mtx); 655 656 for (i = sc->sc_pstate_max; i < sc->sc_pstate_count; i++) { 657 658 if (sc->sc_pstate[i].ps_freq == 0) 659 continue; 660 661 if (sc->sc_pstate[i].ps_freq == freq) { 662 ps = &sc->sc_pstate[i]; 663 break; 664 } 665 } 666 667 mutex_exit(&sc->sc_mtx); 668 669 if (__predict_false(ps == NULL)) { 670 rv = EINVAL; 671 goto fail; 672 } 673 674 switch (method) { 675 676 case ACPI_ADR_SPACE_FIXED_HARDWARE: 677 678 rv = acpicpu_md_pstate_set(ps); 679 680 if (rv != 0) 681 goto fail; 682 683 break; 684 685 case ACPI_ADR_SPACE_SYSTEM_IO: 686 687 addr = sc->sc_pstate_control.reg_addr; 688 width = sc->sc_pstate_control.reg_bitwidth; 689 690 (void)AcpiOsWritePort(addr, ps->ps_control, width); 691 692 addr = sc->sc_pstate_status.reg_addr; 693 width = sc->sc_pstate_status.reg_bitwidth; 694 695 /* 696 * Some systems take longer to respond 697 * than the reported worst-case latency. 698 */ 699 for (i = val = 0; i < ACPICPU_P_STATE_RETRY; i++) { 700 701 (void)AcpiOsReadPort(addr, &val, width); 702 703 if (val == ps->ps_status) 704 break; 705 706 DELAY(ps->ps_latency); 707 } 708 709 if (i == ACPICPU_P_STATE_RETRY) { 710 rv = EAGAIN; 711 goto fail; 712 } 713 714 break; 715 716 default: 717 rv = ENOTTY; 718 goto fail; 719 } 720 721 mutex_enter(&sc->sc_mtx); 722 ps->ps_evcnt.ev_count++; 723 sc->sc_pstate_current = freq; 724 mutex_exit(&sc->sc_mtx); 725 726 return 0; 727 728 fail: 729 aprint_error_dev(sc->sc_dev, "failed to set " 730 "frequency to %u (err %d)\n", freq, rv); 731 732 mutex_enter(&sc->sc_mtx); 733 sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN; 734 mutex_exit(&sc->sc_mtx); 735 736 return rv; 737 } 738
Indexes created Tue Sep 30 20:09:53 GMT 2025