1 /* $NetBSD: acpi_cpu_pstate.c,v 1.39 2011/02/25 09:16:00 jruoho Exp $ */ 2 3 /*- 4 * Copyright (c) 2010, 2011 Jukka Ruohonen <jruohonen@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 1.39 2011/02/25 09:16:00 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 *); 48 static ACPI_STATUS acpicpu_pstate_pss_add(struct acpicpu_pstate *, 49 ACPI_OBJECT *); 50 static ACPI_STATUS acpicpu_pstate_xpss(struct acpicpu_softc *); 51 static ACPI_STATUS acpicpu_pstate_xpss_add(struct acpicpu_pstate *, 52 ACPI_OBJECT *); 53 static ACPI_STATUS acpicpu_pstate_pct(struct acpicpu_softc *); 54 static int acpicpu_pstate_max(struct acpicpu_softc *); 55 static int acpicpu_pstate_min(struct acpicpu_softc *); 56 static void acpicpu_pstate_change(struct acpicpu_softc *); 57 static void acpicpu_pstate_reset(struct acpicpu_softc *); 58 static void acpicpu_pstate_bios(void); 59 60 static uint32_t acpicpu_pstate_saved = 0; 61 62 void 63 acpicpu_pstate_attach(device_t self) 64 { 65 struct acpicpu_softc *sc = device_private(self); 66 const char *str; 67 ACPI_HANDLE tmp; 68 ACPI_STATUS rv; 69 70 rv = acpicpu_pstate_pss(sc); 71 72 if (ACPI_FAILURE(rv)) { 73 str = "_PSS"; 74 goto fail; 75 } 76 77 /* 78 * Append additional information from the extended _PSS, 79 * if available. Note that XPSS can not be used on Intel 80 * systems that use either _PDC or _OSC. From the XPSS 81 * method specification: 82 * 83 * "The platform must not require the use of the 84 * optional _PDC or _OSC methods to coordinate 85 * between the operating system and firmware for 86 * the purposes of enabling specific processor 87 * power management features or implementations." 88 */ 89 if (sc->sc_cap == 0) { 90 91 rv = acpicpu_pstate_xpss(sc); 92 93 if (ACPI_SUCCESS(rv)) 94 sc->sc_flags |= ACPICPU_FLAG_P_XPSS; 95 } 96 97 rv = acpicpu_pstate_pct(sc); 98 99 if (ACPI_FAILURE(rv)) { 100 str = "_PCT"; 101 goto fail; 102 } 103 104 /* 105 * The ACPI 3.0 and 4.0 specifications mandate three 106 * objects for P-states: _PSS, _PCT, and _PPC. A less 107 * strict wording is however used in the earlier 2.0 108 * standard, and some systems conforming to ACPI 2.0 109 * do not have _PPC, the method for dynamic maximum. 110 */ 111 rv = AcpiGetHandle(sc->sc_node->ad_handle, "_PPC", &tmp); 112 113 if (ACPI_FAILURE(rv)) 114 aprint_debug_dev(self, "_PPC missing\n"); 115 116 /* 117 * Employ the XPSS structure by filling 118 * it with MD information required for FFH. 119 */ 120 rv = acpicpu_md_pstate_pss(sc); 121 122 if (rv != 0) { 123 rv = AE_SUPPORT; 124 goto fail; 125 } 126 127 sc->sc_flags |= ACPICPU_FLAG_P; 128 129 acpicpu_pstate_bios(); 130 acpicpu_pstate_reset(sc); 131 acpicpu_pstate_attach_evcnt(sc); 132 acpicpu_pstate_attach_print(sc); 133 134 return; 135 136 fail: 137 switch (rv) { 138 139 case AE_NOT_FOUND: 140 return; 141 142 case AE_SUPPORT: 143 aprint_verbose_dev(self, "P-states not supported\n"); 144 return; 145 146 default: 147 aprint_error_dev(self, "failed to evaluate " 148 "%s: %s\n", str, AcpiFormatException(rv)); 149 } 150 } 151 152 static void 153 acpicpu_pstate_attach_print(struct acpicpu_softc *sc) 154 { 155 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 156 struct acpicpu_pstate *ps; 157 static bool once = false; 158 const char *str; 159 uint32_t i; 160 161 if (once != false) 162 return; 163 164 str = (method != ACPI_ADR_SPACE_SYSTEM_IO) ? "FFH" : "I/O"; 165 166 for (i = 0; i < sc->sc_pstate_count; i++) { 167 168 ps = &sc->sc_pstate[i]; 169 170 if (ps->ps_freq == 0) 171 continue; 172 173 aprint_verbose_dev(sc->sc_dev, "P%d: %3s, " 174 "lat %3u us, pow %5u mW, %4u MHz\n", i, str, 175 ps->ps_latency, ps->ps_power, ps->ps_freq); 176 } 177 178 once = true; 179 } 180 181 static void 182 acpicpu_pstate_attach_evcnt(struct acpicpu_softc *sc) 183 { 184 struct acpicpu_pstate *ps; 185 uint32_t i; 186 187 for (i = 0; i < sc->sc_pstate_count; i++) { 188 189 ps = &sc->sc_pstate[i]; 190 191 if (ps->ps_freq == 0) 192 continue; 193 194 (void)snprintf(ps->ps_name, sizeof(ps->ps_name), 195 "P%u (%u MHz)", i, ps->ps_freq); 196 197 evcnt_attach_dynamic(&ps->ps_evcnt, EVCNT_TYPE_MISC, 198 NULL, device_xname(sc->sc_dev), ps->ps_name); 199 } 200 } 201 202 int 203 acpicpu_pstate_detach(device_t self) 204 { 205 struct acpicpu_softc *sc = device_private(self); 206 static ONCE_DECL(once_detach); 207 size_t size; 208 int rv; 209 210 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) 211 return 0; 212 213 rv = RUN_ONCE(&once_detach, acpicpu_md_pstate_stop); 214 215 if (rv != 0) 216 return rv; 217 218 size = sc->sc_pstate_count * sizeof(*sc->sc_pstate); 219 220 if (sc->sc_pstate != NULL) 221 kmem_free(sc->sc_pstate, size); 222 223 sc->sc_flags &= ~ACPICPU_FLAG_P; 224 acpicpu_pstate_detach_evcnt(sc); 225 226 return 0; 227 } 228 229 static void 230 acpicpu_pstate_detach_evcnt(struct acpicpu_softc *sc) 231 { 232 struct acpicpu_pstate *ps; 233 uint32_t i; 234 235 for (i = 0; i < sc->sc_pstate_count; i++) { 236 237 ps = &sc->sc_pstate[i]; 238 239 if (ps->ps_freq != 0) 240 evcnt_detach(&ps->ps_evcnt); 241 } 242 } 243 244 void 245 acpicpu_pstate_start(device_t self) 246 { 247 struct acpicpu_softc *sc = device_private(self); 248 struct acpicpu_pstate *ps; 249 uint32_t i; 250 int rv; 251 252 rv = acpicpu_md_pstate_start(sc); 253 254 if (rv != 0) 255 goto fail; 256 257 /* 258 * Initialize the state to P0. 259 */ 260 for (i = 0, rv = ENXIO; i < sc->sc_pstate_count; i++) { 261 262 ps = &sc->sc_pstate[i]; 263 264 if (ps->ps_freq != 0) { 265 sc->sc_cold = false; 266 rv = acpicpu_pstate_set(sc, ps->ps_freq); 267 break; 268 } 269 } 270 271 if (rv != 0) 272 goto fail; 273 274 return; 275 276 fail: 277 sc->sc_flags &= ~ACPICPU_FLAG_P; 278 279 if (rv == EEXIST) { 280 aprint_error_dev(self, "driver conflicts with existing one\n"); 281 return; 282 } 283 284 aprint_error_dev(self, "failed to start P-states (err %d)\n", rv); 285 } 286 287 bool 288 acpicpu_pstate_suspend(device_t self) 289 { 290 struct acpicpu_softc *sc = device_private(self); 291 struct acpicpu_pstate *ps = NULL; 292 int32_t i; 293 294 mutex_enter(&sc->sc_mtx); 295 acpicpu_pstate_reset(sc); 296 mutex_exit(&sc->sc_mtx); 297 298 if (acpicpu_pstate_saved != 0) 299 return true; 300 301 /* 302 * Following design notes for Windows, we set the highest 303 * P-state when entering any of the system sleep states. 304 * When resuming, the saved P-state will be restored. 305 * 306 * Microsoft Corporation: Windows Native Processor 307 * Performance Control. Version 1.1a, November, 2002. 308 */ 309 for (i = sc->sc_pstate_count - 1; i >= 0; i--) { 310 311 if (sc->sc_pstate[i].ps_freq != 0) { 312 ps = &sc->sc_pstate[i]; 313 break; 314 } 315 } 316 317 if (__predict_false(ps == NULL)) 318 return true; 319 320 mutex_enter(&sc->sc_mtx); 321 acpicpu_pstate_saved = sc->sc_pstate_current; 322 mutex_exit(&sc->sc_mtx); 323 324 if (acpicpu_pstate_saved == ps->ps_freq) 325 return true; 326 327 (void)acpicpu_pstate_set(sc, ps->ps_freq); 328 329 return true; 330 } 331 332 bool 333 acpicpu_pstate_resume(device_t self) 334 { 335 struct acpicpu_softc *sc = device_private(self); 336 337 if (acpicpu_pstate_saved != 0) { 338 (void)acpicpu_pstate_set(sc, acpicpu_pstate_saved); 339 acpicpu_pstate_saved = 0; 340 } 341 342 return true; 343 } 344 345 void 346 acpicpu_pstate_callback(void *aux) 347 { 348 struct acpicpu_softc *sc; 349 device_t self = aux; 350 uint32_t old, new; 351 352 sc = device_private(self); 353 354 mutex_enter(&sc->sc_mtx); 355 356 old = sc->sc_pstate_max; 357 acpicpu_pstate_change(sc); 358 new = sc->sc_pstate_max; 359 360 if (old == new) { 361 mutex_exit(&sc->sc_mtx); 362 return; 363 } 364 365 mutex_exit(&sc->sc_mtx); 366 367 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "maximum frequency " 368 "changed from P%u (%u MHz) to P%u (%u MHz)\n", 369 old, sc->sc_pstate[old].ps_freq, new, 370 sc->sc_pstate[sc->sc_pstate_max].ps_freq)); 371 372 (void)acpicpu_pstate_set(sc, sc->sc_pstate[new].ps_freq); 373 } 374 375 ACPI_STATUS 376 acpicpu_pstate_pss(struct acpicpu_softc *sc) 377 { 378 struct acpicpu_pstate *ps; 379 ACPI_OBJECT *obj; 380 ACPI_BUFFER buf; 381 ACPI_STATUS rv; 382 uint32_t count; 383 uint32_t i, j; 384 385 rv = acpi_eval_struct(sc->sc_node->ad_handle, "_PSS", &buf); 386 387 if (ACPI_FAILURE(rv)) 388 return rv; 389 390 obj = buf.Pointer; 391 392 if (obj->Type != ACPI_TYPE_PACKAGE) { 393 rv = AE_TYPE; 394 goto out; 395 } 396 397 sc->sc_pstate_count = obj->Package.Count; 398 399 if (sc->sc_pstate_count == 0) { 400 rv = AE_NOT_EXIST; 401 goto out; 402 } 403 404 if (sc->sc_pstate_count > ACPICPU_P_STATE_MAX) { 405 rv = AE_LIMIT; 406 goto out; 407 } 408 409 sc->sc_pstate = kmem_zalloc(sc->sc_pstate_count * 410 sizeof(struct acpicpu_pstate), KM_SLEEP); 411 412 if (sc->sc_pstate == NULL) { 413 rv = AE_NO_MEMORY; 414 goto out; 415 } 416 417 for (count = i = 0; i < sc->sc_pstate_count; i++) { 418 419 ps = &sc->sc_pstate[i]; 420 rv = acpicpu_pstate_pss_add(ps, &obj->Package.Elements[i]); 421 422 if (ACPI_FAILURE(rv)) { 423 aprint_error_dev(sc->sc_dev, "failed to add " 424 "P-state: %s\n", AcpiFormatException(rv)); 425 ps->ps_freq = 0; 426 continue; 427 } 428 429 for (j = 0; j < i; j++) { 430 431 if (ps->ps_freq >= sc->sc_pstate[j].ps_freq) { 432 ps->ps_freq = 0; 433 break; 434 } 435 } 436 437 if (ps->ps_freq != 0) 438 count++; 439 } 440 441 rv = (count != 0) ? AE_OK : AE_NOT_EXIST; 442 443 out: 444 if (buf.Pointer != NULL) 445 ACPI_FREE(buf.Pointer); 446 447 return rv; 448 } 449 450 static ACPI_STATUS 451 acpicpu_pstate_pss_add(struct acpicpu_pstate *ps, ACPI_OBJECT *obj) 452 { 453 ACPI_OBJECT *elm; 454 int i; 455 456 if (obj->Type != ACPI_TYPE_PACKAGE) 457 return AE_TYPE; 458 459 if (obj->Package.Count != 6) 460 return AE_BAD_DATA; 461 462 elm = obj->Package.Elements; 463 464 for (i = 0; i < 6; i++) { 465 466 if (elm[i].Type != ACPI_TYPE_INTEGER) 467 return AE_TYPE; 468 469 if (elm[i].Integer.Value > UINT32_MAX) 470 return AE_AML_NUMERIC_OVERFLOW; 471 } 472 473 ps->ps_freq = elm[0].Integer.Value; 474 ps->ps_power = elm[1].Integer.Value; 475 ps->ps_latency = elm[2].Integer.Value; 476 ps->ps_latency_bm = elm[3].Integer.Value; 477 ps->ps_control = elm[4].Integer.Value; 478 ps->ps_status = elm[5].Integer.Value; 479 480 if (ps->ps_freq == 0 || ps->ps_freq > 9999) 481 return AE_BAD_DECIMAL_CONSTANT; 482 483 if (ps->ps_latency == 0 || ps->ps_latency > 1000) 484 ps->ps_latency = 1; 485 486 return AE_OK; 487 } 488 489 static ACPI_STATUS 490 acpicpu_pstate_xpss(struct acpicpu_softc *sc) 491 { 492 struct acpicpu_pstate *ps; 493 ACPI_OBJECT *obj; 494 ACPI_BUFFER buf; 495 ACPI_STATUS rv; 496 uint32_t i = 0; 497 498 rv = acpi_eval_struct(sc->sc_node->ad_handle, "XPSS", &buf); 499 500 if (ACPI_FAILURE(rv)) 501 goto out; 502 503 obj = buf.Pointer; 504 505 if (obj->Type != ACPI_TYPE_PACKAGE) { 506 rv = AE_TYPE; 507 goto out; 508 } 509 510 if (obj->Package.Count != sc->sc_pstate_count) { 511 rv = AE_LIMIT; 512 goto out; 513 } 514 515 while (i < sc->sc_pstate_count) { 516 517 ps = &sc->sc_pstate[i]; 518 acpicpu_pstate_xpss_add(ps, &obj->Package.Elements[i]); 519 520 i++; 521 } 522 523 out: 524 if (ACPI_FAILURE(rv) && rv != AE_NOT_FOUND) 525 aprint_error_dev(sc->sc_dev, "failed to evaluate " 526 "XPSS: %s\n", AcpiFormatException(rv)); 527 528 if (buf.Pointer != NULL) 529 ACPI_FREE(buf.Pointer); 530 531 return rv; 532 } 533 534 static ACPI_STATUS 535 acpicpu_pstate_xpss_add(struct acpicpu_pstate *ps, ACPI_OBJECT *obj) 536 { 537 ACPI_OBJECT *elm; 538 int i; 539 540 if (obj->Type != ACPI_TYPE_PACKAGE) 541 return AE_TYPE; 542 543 if (obj->Package.Count != 8) 544 return AE_BAD_DATA; 545 546 elm = obj->Package.Elements; 547 548 for (i = 0; i < 4; i++) { 549 550 if (elm[i].Type != ACPI_TYPE_INTEGER) 551 return AE_TYPE; 552 553 if (elm[i].Integer.Value > UINT32_MAX) 554 return AE_AML_NUMERIC_OVERFLOW; 555 } 556 557 for (; i < 8; i++) { 558 559 if (elm[i].Type != ACPI_TYPE_BUFFER) 560 return AE_TYPE; 561 562 if (elm[i].Buffer.Length != 8) 563 return AE_LIMIT; 564 } 565 566 /* 567 * Only overwrite the elements that were 568 * not available from the conventional _PSS. 569 */ 570 if (ps->ps_freq == 0) 571 ps->ps_freq = elm[0].Integer.Value; 572 573 if (ps->ps_power == 0) 574 ps->ps_power = elm[1].Integer.Value; 575 576 if (ps->ps_latency == 0) 577 ps->ps_latency = elm[2].Integer.Value; 578 579 if (ps->ps_latency_bm == 0) 580 ps->ps_latency_bm = elm[3].Integer.Value; 581 582 if (ps->ps_control == 0) 583 ps->ps_control = ACPI_GET64(elm[4].Buffer.Pointer); 584 585 if (ps->ps_status == 0) 586 ps->ps_status = ACPI_GET64(elm[5].Buffer.Pointer); 587 588 if (ps->ps_control_mask == 0) 589 ps->ps_control_mask = ACPI_GET64(elm[6].Buffer.Pointer); 590 591 if (ps->ps_status_mask == 0) 592 ps->ps_status_mask = ACPI_GET64(elm[7].Buffer.Pointer); 593 594 ps->ps_flags |= ACPICPU_FLAG_P_XPSS; 595 596 if (ps->ps_freq == 0 || ps->ps_freq > 9999) 597 return AE_BAD_DECIMAL_CONSTANT; 598 599 if (ps->ps_latency == 0 || ps->ps_latency > 1000) 600 ps->ps_latency = 1; 601 602 return AE_OK; 603 } 604 605 ACPI_STATUS 606 acpicpu_pstate_pct(struct acpicpu_softc *sc) 607 { 608 static const size_t size = sizeof(struct acpicpu_reg); 609 struct acpicpu_reg *reg[2]; 610 struct acpicpu_pstate *ps; 611 ACPI_OBJECT *elm, *obj; 612 ACPI_BUFFER buf; 613 ACPI_STATUS rv; 614 uint8_t width; 615 uint32_t i; 616 617 rv = acpi_eval_struct(sc->sc_node->ad_handle, "_PCT", &buf); 618 619 if (ACPI_FAILURE(rv)) 620 return rv; 621 622 obj = buf.Pointer; 623 624 if (obj->Type != ACPI_TYPE_PACKAGE) { 625 rv = AE_TYPE; 626 goto out; 627 } 628 629 if (obj->Package.Count != 2) { 630 rv = AE_LIMIT; 631 goto out; 632 } 633 634 for (i = 0; i < 2; i++) { 635 636 elm = &obj->Package.Elements[i]; 637 638 if (elm->Type != ACPI_TYPE_BUFFER) { 639 rv = AE_TYPE; 640 goto out; 641 } 642 643 if (size > elm->Buffer.Length) { 644 rv = AE_AML_BAD_RESOURCE_LENGTH; 645 goto out; 646 } 647 648 reg[i] = (struct acpicpu_reg *)elm->Buffer.Pointer; 649 650 switch (reg[i]->reg_spaceid) { 651 652 case ACPI_ADR_SPACE_SYSTEM_IO: 653 654 if (reg[i]->reg_addr == 0) { 655 rv = AE_AML_ILLEGAL_ADDRESS; 656 goto out; 657 } 658 659 width = reg[i]->reg_bitwidth; 660 661 if (width + reg[i]->reg_bitoffset > 32) { 662 rv = AE_AML_BAD_RESOURCE_VALUE; 663 goto out; 664 } 665 666 if (width != 8 && width != 16 && width != 32) { 667 rv = AE_AML_BAD_RESOURCE_VALUE; 668 goto out; 669 } 670 671 break; 672 673 case ACPI_ADR_SPACE_FIXED_HARDWARE: 674 675 if ((sc->sc_flags & ACPICPU_FLAG_P_XPSS) != 0) { 676 677 if (reg[i]->reg_bitwidth != 64) { 678 rv = AE_AML_BAD_RESOURCE_VALUE; 679 goto out; 680 } 681 682 if (reg[i]->reg_bitoffset != 0) { 683 rv = AE_AML_BAD_RESOURCE_VALUE; 684 goto out; 685 } 686 687 break; 688 } 689 690 if ((sc->sc_flags & ACPICPU_FLAG_P_FFH) == 0) { 691 rv = AE_SUPPORT; 692 goto out; 693 } 694 695 break; 696 697 default: 698 rv = AE_AML_INVALID_SPACE_ID; 699 goto out; 700 } 701 } 702 703 if (reg[0]->reg_spaceid != reg[1]->reg_spaceid) { 704 rv = AE_AML_INVALID_SPACE_ID; 705 goto out; 706 } 707 708 (void)memcpy(&sc->sc_pstate_control, reg[0], size); 709 (void)memcpy(&sc->sc_pstate_status, reg[1], size); 710 711 if ((sc->sc_flags & ACPICPU_FLAG_P_XPSS) == 0) 712 goto out; 713 714 /* 715 * In XPSS the control address can not be zero, 716 * but the status address may be. In this case, 717 * comparable to T-states, we can ignore the status 718 * check during the P-state (FFH) transition. 719 */ 720 if (sc->sc_pstate_control.reg_addr == 0) { 721 rv = AE_AML_BAD_RESOURCE_LENGTH; 722 goto out; 723 } 724 725 /* 726 * If XPSS is present, copy the MSR addresses 727 * to the P-state structures for convenience. 728 */ 729 for (i = 0; i < sc->sc_pstate_count; i++) { 730 731 ps = &sc->sc_pstate[i]; 732 733 if (ps->ps_freq == 0) 734 continue; 735 736 ps->ps_status_addr = sc->sc_pstate_status.reg_addr; 737 ps->ps_control_addr = sc->sc_pstate_control.reg_addr; 738 } 739 740 out: 741 if (buf.Pointer != NULL) 742 ACPI_FREE(buf.Pointer); 743 744 return rv; 745 } 746 747 static int 748 acpicpu_pstate_max(struct acpicpu_softc *sc) 749 { 750 ACPI_INTEGER val; 751 ACPI_STATUS rv; 752 753 /* 754 * Evaluate the currently highest P-state that can be used. 755 * If available, we can use either this state or any lower 756 * power (i.e. higher numbered) state from the _PSS object. 757 * Note that the return value must match the _OST parameter. 758 */ 759 rv = acpi_eval_integer(sc->sc_node->ad_handle, "_PPC", &val); 760 761 if (ACPI_SUCCESS(rv) && val < sc->sc_pstate_count) { 762 763 if (sc->sc_pstate[val].ps_freq != 0) { 764 sc->sc_pstate_max = val; 765 return 0; 766 } 767 } 768 769 return 1; 770 } 771 772 static int 773 acpicpu_pstate_min(struct acpicpu_softc *sc) 774 { 775 ACPI_INTEGER val; 776 ACPI_STATUS rv; 777 778 /* 779 * The _PDL object defines the minimum when passive cooling 780 * is being performed. If available, we can use the returned 781 * state or any higher power (i.e. lower numbered) state. 782 */ 783 rv = acpi_eval_integer(sc->sc_node->ad_handle, "_PDL", &val); 784 785 if (ACPI_SUCCESS(rv) && val < sc->sc_pstate_count) { 786 787 if (sc->sc_pstate[val].ps_freq == 0) 788 return 1; 789 790 if (val >= sc->sc_pstate_max) { 791 sc->sc_pstate_min = val; 792 return 0; 793 } 794 } 795 796 return 1; 797 } 798 799 static void 800 acpicpu_pstate_change(struct acpicpu_softc *sc) 801 { 802 static ACPI_STATUS rv = AE_OK; 803 ACPI_OBJECT_LIST arg; 804 ACPI_OBJECT obj[2]; 805 static int val = 0; 806 807 acpicpu_pstate_reset(sc); 808 809 /* 810 * Cache the checks as the optional 811 * _PDL and _OST are rarely present. 812 */ 813 if (val == 0) 814 val = acpicpu_pstate_min(sc); 815 816 arg.Count = 2; 817 arg.Pointer = obj; 818 819 obj[0].Type = ACPI_TYPE_INTEGER; 820 obj[1].Type = ACPI_TYPE_INTEGER; 821 822 obj[0].Integer.Value = ACPICPU_P_NOTIFY; 823 obj[1].Integer.Value = acpicpu_pstate_max(sc); 824 825 if (ACPI_FAILURE(rv)) 826 return; 827 828 rv = AcpiEvaluateObject(sc->sc_node->ad_handle, "_OST", &arg, NULL); 829 } 830 831 static void 832 acpicpu_pstate_reset(struct acpicpu_softc *sc) 833 { 834 835 sc->sc_pstate_max = 0; 836 sc->sc_pstate_min = sc->sc_pstate_count - 1; 837 838 } 839 840 static void 841 acpicpu_pstate_bios(void) 842 { 843 const uint8_t val = AcpiGbl_FADT.PstateControl; 844 const uint32_t addr = AcpiGbl_FADT.SmiCommand; 845 846 if (addr == 0 || val == 0) 847 return; 848 849 (void)AcpiOsWritePort(addr, val, 8); 850 } 851 852 int 853 acpicpu_pstate_get(struct acpicpu_softc *sc, uint32_t *freq) 854 { 855 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 856 struct acpicpu_pstate *ps = NULL; 857 uint32_t i, val = 0; 858 uint64_t addr; 859 uint8_t width; 860 int rv; 861 862 if (__predict_false(sc->sc_cold != false)) { 863 rv = EBUSY; 864 goto fail; 865 } 866 867 if (__predict_false((sc->sc_flags & ACPICPU_FLAG_P) == 0)) { 868 rv = ENODEV; 869 goto fail; 870 } 871 872 mutex_enter(&sc->sc_mtx); 873 874 /* 875 * Use the cached value, if available. 876 */ 877 if (sc->sc_pstate_current != ACPICPU_P_STATE_UNKNOWN) { 878 *freq = sc->sc_pstate_current; 879 mutex_exit(&sc->sc_mtx); 880 return 0; 881 } 882 883 mutex_exit(&sc->sc_mtx); 884 885 switch (method) { 886 887 case ACPI_ADR_SPACE_FIXED_HARDWARE: 888 889 rv = acpicpu_md_pstate_get(sc, freq); 890 891 if (__predict_false(rv != 0)) 892 goto fail; 893 894 break; 895 896 case ACPI_ADR_SPACE_SYSTEM_IO: 897 898 addr = sc->sc_pstate_status.reg_addr; 899 width = sc->sc_pstate_status.reg_bitwidth; 900 901 (void)AcpiOsReadPort(addr, &val, width); 902 903 if (val == 0) { 904 rv = EIO; 905 goto fail; 906 } 907 908 for (i = 0; i < sc->sc_pstate_count; i++) { 909 910 if (sc->sc_pstate[i].ps_freq == 0) 911 continue; 912 913 if (val == sc->sc_pstate[i].ps_status) { 914 ps = &sc->sc_pstate[i]; 915 break; 916 } 917 } 918 919 if (ps == NULL) { 920 rv = EIO; 921 goto fail; 922 } 923 924 *freq = ps->ps_freq; 925 break; 926 927 default: 928 rv = ENOTTY; 929 goto fail; 930 } 931 932 mutex_enter(&sc->sc_mtx); 933 sc->sc_pstate_current = *freq; 934 mutex_exit(&sc->sc_mtx); 935 936 return 0; 937 938 fail: 939 aprint_error_dev(sc->sc_dev, "failed " 940 "to get frequency (err %d)\n", rv); 941 942 mutex_enter(&sc->sc_mtx); 943 *freq = sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN; 944 mutex_exit(&sc->sc_mtx); 945 946 return rv; 947 } 948 949 int 950 acpicpu_pstate_set(struct acpicpu_softc *sc, uint32_t freq) 951 { 952 const uint8_t method = sc->sc_pstate_control.reg_spaceid; 953 struct acpicpu_pstate *ps = NULL; 954 uint32_t i, val; 955 uint64_t addr; 956 uint8_t width; 957 int rv; 958 959 if (__predict_false(sc->sc_cold != false)) { 960 rv = EBUSY; 961 goto fail; 962 } 963 964 if (__predict_false((sc->sc_flags & ACPICPU_FLAG_P) == 0)) { 965 rv = ENODEV; 966 goto fail; 967 } 968 969 mutex_enter(&sc->sc_mtx); 970 971 if (sc->sc_pstate_current == freq) { 972 mutex_exit(&sc->sc_mtx); 973 return 0; 974 } 975 976 /* 977 * Verify that the requested frequency is available. 978 * 979 * The access needs to be protected since the currently 980 * available maximum and minimum may change dynamically. 981 */ 982 for (i = sc->sc_pstate_max; i <= sc->sc_pstate_min; i++) { 983 984 if (__predict_false(sc->sc_pstate[i].ps_freq == 0)) 985 continue; 986 987 if (sc->sc_pstate[i].ps_freq == freq) { 988 ps = &sc->sc_pstate[i]; 989 break; 990 } 991 } 992 993 mutex_exit(&sc->sc_mtx); 994 995 if (__predict_false(ps == NULL)) { 996 rv = EINVAL; 997 goto fail; 998 } 999 1000 switch (method) { 1001 1002 case ACPI_ADR_SPACE_FIXED_HARDWARE: 1003 1004 rv = acpicpu_md_pstate_set(ps); 1005 1006 if (__predict_false(rv != 0)) 1007 goto fail; 1008 1009 break; 1010 1011 case ACPI_ADR_SPACE_SYSTEM_IO: 1012 1013 addr = sc->sc_pstate_control.reg_addr; 1014 width = sc->sc_pstate_control.reg_bitwidth; 1015 1016 (void)AcpiOsWritePort(addr, ps->ps_control, width); 1017 1018 addr = sc->sc_pstate_status.reg_addr; 1019 width = sc->sc_pstate_status.reg_bitwidth; 1020 1021 /* 1022 * Some systems take longer to respond 1023 * than the reported worst-case latency. 1024 */ 1025 for (i = val = 0; i < ACPICPU_P_STATE_RETRY; i++) { 1026 1027 (void)AcpiOsReadPort(addr, &val, width); 1028 1029 if (val == ps->ps_status) 1030 break; 1031 1032 DELAY(ps->ps_latency); 1033 } 1034 1035 if (i == ACPICPU_P_STATE_RETRY) { 1036 rv = EAGAIN; 1037 goto fail; 1038 } 1039 1040 break; 1041 1042 default: 1043 rv = ENOTTY; 1044 goto fail; 1045 } 1046 1047 mutex_enter(&sc->sc_mtx); 1048 ps->ps_evcnt.ev_count++; 1049 sc->sc_pstate_current = freq; 1050 mutex_exit(&sc->sc_mtx); 1051 1052 return 0; 1053 1054 fail: 1055 aprint_error_dev(sc->sc_dev, "failed to set " 1056 "frequency to %u (err %d)\n", freq, rv); 1057 1058 mutex_enter(&sc->sc_mtx); 1059 sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN; 1060 mutex_exit(&sc->sc_mtx); 1061 1062 return rv; 1063 } 1064