1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * processor_throttling.c - Throttling submodule of the ACPI processor driver 4 * 5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 7 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> 8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 9 * - Added processor hotplug support 10 */ 11 12 #define pr_fmt(fmt) "ACPI: " fmt 13 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/slab.h> 17 #include <linux/init.h> 18 #include <linux/sched.h> 19 #include <linux/cpufreq.h> 20 #include <linux/acpi.h> 21 #include <acpi/processor.h> 22 #include <asm/io.h> 23 #include <linux/uaccess.h> 24 25 /* ignore_tpc: 26 * 0 -> acpi processor driver doesn't ignore _TPC values 27 * 1 -> acpi processor driver ignores _TPC values 28 */ 29 static int ignore_tpc; 30 module_param(ignore_tpc, int, 0644); 31 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support"); 32 33 struct throttling_tstate { 34 unsigned int cpu; /* cpu nr */ 35 int target_state; /* target T-state */ 36 }; 37 38 struct acpi_processor_throttling_arg { 39 struct acpi_processor *pr; 40 int target_state; 41 bool force; 42 }; 43 44 #define THROTTLING_PRECHANGE (1) 45 #define THROTTLING_POSTCHANGE (2) 46 47 static int acpi_processor_get_throttling(struct acpi_processor *pr); 48 static int __acpi_processor_set_throttling(struct acpi_processor *pr, 49 int state, bool force, bool direct); 50 51 static int acpi_processor_update_tsd_coord(void) 52 { 53 int count, count_target; 54 int retval = 0; 55 unsigned int i, j; 56 cpumask_var_t covered_cpus; 57 struct acpi_processor *pr, *match_pr; 58 struct acpi_tsd_package *pdomain, *match_pdomain; 59 struct acpi_processor_throttling *pthrottling, *match_pthrottling; 60 61 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) 62 return -ENOMEM; 63 64 /* 65 * Now that we have _TSD data from all CPUs, lets setup T-state 66 * coordination between all CPUs. 67 */ 68 for_each_possible_cpu(i) { 69 pr = per_cpu(processors, i); 70 if (!pr) 71 continue; 72 73 /* Basic validity check for domain info */ 74 pthrottling = &(pr->throttling); 75 76 /* 77 * If tsd package for one cpu is invalid, the coordination 78 * among all CPUs is thought as invalid. 79 * Maybe it is ugly. 80 */ 81 if (!pthrottling->tsd_valid_flag) { 82 retval = -EINVAL; 83 break; 84 } 85 } 86 if (retval) 87 goto err_ret; 88 89 for_each_possible_cpu(i) { 90 pr = per_cpu(processors, i); 91 if (!pr) 92 continue; 93 94 if (cpumask_test_cpu(i, covered_cpus)) 95 continue; 96 pthrottling = &pr->throttling; 97 98 pdomain = &(pthrottling->domain_info); 99 cpumask_set_cpu(i, pthrottling->shared_cpu_map); 100 cpumask_set_cpu(i, covered_cpus); 101 /* 102 * If the number of processor in the TSD domain is 1, it is 103 * unnecessary to parse the coordination for this CPU. 104 */ 105 if (pdomain->num_processors <= 1) 106 continue; 107 108 /* Validate the Domain info */ 109 count_target = pdomain->num_processors; 110 count = 1; 111 112 for_each_possible_cpu(j) { 113 if (i == j) 114 continue; 115 116 match_pr = per_cpu(processors, j); 117 if (!match_pr) 118 continue; 119 120 match_pthrottling = &(match_pr->throttling); 121 match_pdomain = &(match_pthrottling->domain_info); 122 if (match_pdomain->domain != pdomain->domain) 123 continue; 124 125 /* Here i and j are in the same domain. 126 * If two TSD packages have the same domain, they 127 * should have the same num_porcessors and 128 * coordination type. Otherwise it will be regarded 129 * as illegal. 130 */ 131 if (match_pdomain->num_processors != count_target) { 132 retval = -EINVAL; 133 goto err_ret; 134 } 135 136 if (pdomain->coord_type != match_pdomain->coord_type) { 137 retval = -EINVAL; 138 goto err_ret; 139 } 140 141 cpumask_set_cpu(j, covered_cpus); 142 cpumask_set_cpu(j, pthrottling->shared_cpu_map); 143 count++; 144 } 145 for_each_possible_cpu(j) { 146 if (i == j) 147 continue; 148 149 match_pr = per_cpu(processors, j); 150 if (!match_pr) 151 continue; 152 153 match_pthrottling = &(match_pr->throttling); 154 match_pdomain = &(match_pthrottling->domain_info); 155 if (match_pdomain->domain != pdomain->domain) 156 continue; 157 158 /* 159 * If some CPUS have the same domain, they 160 * will have the same shared_cpu_map. 161 */ 162 cpumask_copy(match_pthrottling->shared_cpu_map, 163 pthrottling->shared_cpu_map); 164 } 165 } 166 167 err_ret: 168 free_cpumask_var(covered_cpus); 169 170 for_each_possible_cpu(i) { 171 pr = per_cpu(processors, i); 172 if (!pr) 173 continue; 174 175 /* 176 * Assume no coordination on any error parsing domain info. 177 * The coordination type will be forced as SW_ALL. 178 */ 179 if (retval) { 180 pthrottling = &(pr->throttling); 181 cpumask_clear(pthrottling->shared_cpu_map); 182 cpumask_set_cpu(i, pthrottling->shared_cpu_map); 183 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 184 } 185 } 186 187 return retval; 188 } 189 190 /* 191 * Update the T-state coordination after the _TSD 192 * data for all cpus is obtained. 193 */ 194 void acpi_processor_throttling_init(void) 195 { 196 if (acpi_processor_update_tsd_coord()) 197 pr_debug("Assume no T-state coordination\n"); 198 } 199 200 static int acpi_processor_throttling_notifier(unsigned long event, void *data) 201 { 202 struct throttling_tstate *p_tstate = data; 203 struct acpi_processor *pr; 204 unsigned int cpu; 205 int target_state; 206 struct acpi_processor_limit *p_limit; 207 struct acpi_processor_throttling *p_throttling; 208 209 cpu = p_tstate->cpu; 210 pr = per_cpu(processors, cpu); 211 if (!pr) { 212 pr_debug("Invalid pr pointer\n"); 213 return 0; 214 } 215 if (!pr->flags.throttling) { 216 acpi_handle_debug(pr->handle, 217 "Throttling control unsupported on CPU %d\n", 218 cpu); 219 return 0; 220 } 221 target_state = p_tstate->target_state; 222 p_throttling = &(pr->throttling); 223 switch (event) { 224 case THROTTLING_PRECHANGE: 225 /* 226 * Prechange event is used to choose one proper t-state, 227 * which meets the limits of thermal, user and _TPC. 228 */ 229 p_limit = &pr->limit; 230 if (p_limit->thermal.tx > target_state) 231 target_state = p_limit->thermal.tx; 232 if (p_limit->user.tx > target_state) 233 target_state = p_limit->user.tx; 234 if (pr->throttling_platform_limit > target_state) 235 target_state = pr->throttling_platform_limit; 236 if (target_state >= p_throttling->state_count) { 237 pr_warn("Exceed the limit of T-state \n"); 238 target_state = p_throttling->state_count - 1; 239 } 240 p_tstate->target_state = target_state; 241 acpi_handle_debug(pr->handle, 242 "PreChange Event: target T-state of CPU %d is T%d\n", 243 cpu, target_state); 244 break; 245 case THROTTLING_POSTCHANGE: 246 /* 247 * Postchange event is only used to update the 248 * T-state flag of acpi_processor_throttling. 249 */ 250 p_throttling->state = target_state; 251 acpi_handle_debug(pr->handle, 252 "PostChange Event: CPU %d is switched to T%d\n", 253 cpu, target_state); 254 break; 255 default: 256 pr_warn("Unsupported Throttling notifier event\n"); 257 break; 258 } 259 260 return 0; 261 } 262 263 /* 264 * _TPC - Throttling Present Capabilities 265 */ 266 static int acpi_processor_get_platform_limit(struct acpi_processor *pr) 267 { 268 acpi_status status = 0; 269 unsigned long long tpc = 0; 270 271 if (!pr) 272 return -EINVAL; 273 274 if (ignore_tpc) 275 goto end; 276 277 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc); 278 if (ACPI_FAILURE(status)) { 279 if (status != AE_NOT_FOUND) 280 acpi_evaluation_failure_warn(pr->handle, "_TPC", status); 281 282 return -ENODEV; 283 } 284 285 end: 286 pr->throttling_platform_limit = (int)tpc; 287 return 0; 288 } 289 290 int acpi_processor_tstate_has_changed(struct acpi_processor *pr) 291 { 292 int result = 0; 293 int throttling_limit; 294 int current_state; 295 struct acpi_processor_limit *limit; 296 int target_state; 297 298 if (ignore_tpc) 299 return 0; 300 301 result = acpi_processor_get_platform_limit(pr); 302 if (result) { 303 /* Throttling Limit is unsupported */ 304 return result; 305 } 306 307 throttling_limit = pr->throttling_platform_limit; 308 if (throttling_limit >= pr->throttling.state_count) { 309 /* Uncorrect Throttling Limit */ 310 return -EINVAL; 311 } 312 313 current_state = pr->throttling.state; 314 if (current_state > throttling_limit) { 315 /* 316 * The current state can meet the requirement of 317 * _TPC limit. But it is reasonable that OSPM changes 318 * t-states from high to low for better performance. 319 * Of course the limit condition of thermal 320 * and user should be considered. 321 */ 322 limit = &pr->limit; 323 target_state = throttling_limit; 324 if (limit->thermal.tx > target_state) 325 target_state = limit->thermal.tx; 326 if (limit->user.tx > target_state) 327 target_state = limit->user.tx; 328 } else if (current_state == throttling_limit) { 329 /* 330 * Unnecessary to change the throttling state 331 */ 332 return 0; 333 } else { 334 /* 335 * If the current state is lower than the limit of _TPC, it 336 * will be forced to switch to the throttling state defined 337 * by throttling_platfor_limit. 338 * Because the previous state meets with the limit condition 339 * of thermal and user, it is unnecessary to check it again. 340 */ 341 target_state = throttling_limit; 342 } 343 return acpi_processor_set_throttling(pr, target_state, false); 344 } 345 346 /* 347 * This function is used to reevaluate whether the T-state is valid 348 * after one CPU is onlined/offlined. 349 * It is noted that it won't reevaluate the following properties for 350 * the T-state. 351 * 1. Control method. 352 * 2. the number of supported T-state 353 * 3. TSD domain 354 */ 355 void acpi_processor_reevaluate_tstate(struct acpi_processor *pr, 356 bool is_dead) 357 { 358 int result = 0; 359 360 if (is_dead) { 361 /* When one CPU is offline, the T-state throttling 362 * will be invalidated. 363 */ 364 pr->flags.throttling = 0; 365 return; 366 } 367 /* the following is to recheck whether the T-state is valid for 368 * the online CPU 369 */ 370 if (!pr->throttling.state_count) { 371 /* If the number of T-state is invalid, it is 372 * invalidated. 373 */ 374 pr->flags.throttling = 0; 375 return; 376 } 377 pr->flags.throttling = 1; 378 379 /* Disable throttling (if enabled). We'll let subsequent 380 * policy (e.g.thermal) decide to lower performance if it 381 * so chooses, but for now we'll crank up the speed. 382 */ 383 384 result = acpi_processor_get_throttling(pr); 385 if (result) 386 goto end; 387 388 if (pr->throttling.state) { 389 result = acpi_processor_set_throttling(pr, 0, false); 390 if (result) 391 goto end; 392 } 393 394 end: 395 if (result) 396 pr->flags.throttling = 0; 397 } 398 /* 399 * _PTC - Processor Throttling Control (and status) register location 400 */ 401 static int acpi_processor_get_throttling_control(struct acpi_processor *pr) 402 { 403 int result = 0; 404 acpi_status status = 0; 405 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 406 union acpi_object *ptc = NULL; 407 union acpi_object obj; 408 struct acpi_processor_throttling *throttling; 409 410 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer); 411 if (ACPI_FAILURE(status)) { 412 if (status != AE_NOT_FOUND) 413 acpi_evaluation_failure_warn(pr->handle, "_PTC", status); 414 415 return -ENODEV; 416 } 417 418 ptc = (union acpi_object *)buffer.pointer; 419 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE) 420 || (ptc->package.count != 2)) { 421 pr_err("Invalid _PTC data\n"); 422 result = -EFAULT; 423 goto end; 424 } 425 426 /* 427 * control_register 428 */ 429 430 obj = ptc->package.elements[0]; 431 432 if ((obj.type != ACPI_TYPE_BUFFER) 433 || (obj.buffer.length < sizeof(struct acpi_ptc_register)) 434 || (obj.buffer.pointer == NULL)) { 435 pr_err("Invalid _PTC data (control_register)\n"); 436 result = -EFAULT; 437 goto end; 438 } 439 memcpy(&pr->throttling.control_register, obj.buffer.pointer, 440 sizeof(struct acpi_ptc_register)); 441 442 /* 443 * status_register 444 */ 445 446 obj = ptc->package.elements[1]; 447 448 if ((obj.type != ACPI_TYPE_BUFFER) 449 || (obj.buffer.length < sizeof(struct acpi_ptc_register)) 450 || (obj.buffer.pointer == NULL)) { 451 pr_err("Invalid _PTC data (status_register)\n"); 452 result = -EFAULT; 453 goto end; 454 } 455 456 memcpy(&pr->throttling.status_register, obj.buffer.pointer, 457 sizeof(struct acpi_ptc_register)); 458 459 throttling = &pr->throttling; 460 461 if ((throttling->control_register.bit_width + 462 throttling->control_register.bit_offset) > 32) { 463 pr_err("Invalid _PTC control register\n"); 464 result = -EFAULT; 465 goto end; 466 } 467 468 if ((throttling->status_register.bit_width + 469 throttling->status_register.bit_offset) > 32) { 470 pr_err("Invalid _PTC status register\n"); 471 result = -EFAULT; 472 goto end; 473 } 474 475 end: 476 kfree(buffer.pointer); 477 478 return result; 479 } 480 481 /* 482 * _TSS - Throttling Supported States 483 */ 484 static int acpi_processor_get_throttling_states(struct acpi_processor *pr) 485 { 486 int result = 0; 487 acpi_status status = AE_OK; 488 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 489 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" }; 490 struct acpi_buffer state = { 0, NULL }; 491 union acpi_object *tss = NULL; 492 int i; 493 494 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer); 495 if (ACPI_FAILURE(status)) { 496 if (status != AE_NOT_FOUND) 497 acpi_evaluation_failure_warn(pr->handle, "_TSS", status); 498 499 return -ENODEV; 500 } 501 502 tss = buffer.pointer; 503 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) { 504 pr_err("Invalid _TSS data\n"); 505 result = -EFAULT; 506 goto end; 507 } 508 509 acpi_handle_debug(pr->handle, "Found %d throttling states\n", 510 tss->package.count); 511 512 pr->throttling.state_count = tss->package.count; 513 pr->throttling.states_tss = 514 kmalloc_array(tss->package.count, 515 sizeof(struct acpi_processor_tx_tss), 516 GFP_KERNEL); 517 if (!pr->throttling.states_tss) { 518 result = -ENOMEM; 519 goto end; 520 } 521 522 for (i = 0; i < pr->throttling.state_count; i++) { 523 524 struct acpi_processor_tx_tss *tx = 525 (struct acpi_processor_tx_tss *)&(pr->throttling. 526 states_tss[i]); 527 528 state.length = sizeof(struct acpi_processor_tx_tss); 529 state.pointer = tx; 530 531 acpi_handle_debug(pr->handle, "Extracting state %d\n", i); 532 533 status = acpi_extract_package(&(tss->package.elements[i]), 534 &format, &state); 535 if (ACPI_FAILURE(status)) { 536 acpi_handle_warn(pr->handle, "Invalid _TSS data: %s\n", 537 acpi_format_exception(status)); 538 result = -EFAULT; 539 kfree(pr->throttling.states_tss); 540 goto end; 541 } 542 543 if (!tx->freqpercentage) { 544 pr_err("Invalid _TSS data: freq is zero\n"); 545 result = -EFAULT; 546 kfree(pr->throttling.states_tss); 547 goto end; 548 } 549 } 550 551 end: 552 kfree(buffer.pointer); 553 554 return result; 555 } 556 557 /* 558 * _TSD - T-State Dependencies 559 */ 560 static int acpi_processor_get_tsd(struct acpi_processor *pr) 561 { 562 int result = 0; 563 acpi_status status = AE_OK; 564 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 565 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" }; 566 struct acpi_buffer state = { 0, NULL }; 567 union acpi_object *tsd = NULL; 568 struct acpi_tsd_package *pdomain; 569 struct acpi_processor_throttling *pthrottling; 570 571 pthrottling = &pr->throttling; 572 pthrottling->tsd_valid_flag = 0; 573 574 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer); 575 if (ACPI_FAILURE(status)) { 576 if (status != AE_NOT_FOUND) 577 acpi_evaluation_failure_warn(pr->handle, "_TSD", status); 578 579 return -ENODEV; 580 } 581 582 tsd = buffer.pointer; 583 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) { 584 pr_err("Invalid _TSD data\n"); 585 result = -EFAULT; 586 goto end; 587 } 588 589 if (tsd->package.count != 1) { 590 pr_err("Invalid _TSD data\n"); 591 result = -EFAULT; 592 goto end; 593 } 594 595 pdomain = &(pr->throttling.domain_info); 596 597 state.length = sizeof(struct acpi_tsd_package); 598 state.pointer = pdomain; 599 600 status = acpi_extract_package(&(tsd->package.elements[0]), 601 &format, &state); 602 if (ACPI_FAILURE(status)) { 603 pr_err("Invalid _TSD data\n"); 604 result = -EFAULT; 605 goto end; 606 } 607 608 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) { 609 pr_err("Unknown _TSD:num_entries\n"); 610 result = -EFAULT; 611 goto end; 612 } 613 614 if (pdomain->revision != ACPI_TSD_REV0_REVISION) { 615 pr_err("Unknown _TSD:revision\n"); 616 result = -EFAULT; 617 goto end; 618 } 619 620 pthrottling = &pr->throttling; 621 pthrottling->tsd_valid_flag = 1; 622 pthrottling->shared_type = pdomain->coord_type; 623 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); 624 /* 625 * If the coordination type is not defined in ACPI spec, 626 * the tsd_valid_flag will be clear and coordination type 627 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL. 628 */ 629 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && 630 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && 631 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { 632 pthrottling->tsd_valid_flag = 0; 633 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 634 } 635 636 end: 637 kfree(buffer.pointer); 638 return result; 639 } 640 641 /* -------------------------------------------------------------------------- 642 Throttling Control 643 -------------------------------------------------------------------------- */ 644 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr) 645 { 646 int state = 0; 647 u32 value = 0; 648 u32 duty_mask = 0; 649 u32 duty_value = 0; 650 651 if (!pr) 652 return -EINVAL; 653 654 if (!pr->flags.throttling) 655 return -ENODEV; 656 657 /* 658 * We don't care about error returns - we just try to mark 659 * these reserved so that nobody else is confused into thinking 660 * that this region might be unused.. 661 * 662 * (In particular, allocating the IO range for Cardbus) 663 */ 664 request_region(pr->throttling.address, 6, "ACPI CPU throttle"); 665 666 pr->throttling.state = 0; 667 668 duty_mask = pr->throttling.state_count - 1; 669 670 duty_mask <<= pr->throttling.duty_offset; 671 672 local_irq_disable(); 673 674 value = inl(pr->throttling.address); 675 676 /* 677 * Compute the current throttling state when throttling is enabled 678 * (bit 4 is on). 679 */ 680 if (value & 0x10) { 681 duty_value = value & duty_mask; 682 duty_value >>= pr->throttling.duty_offset; 683 684 if (duty_value) 685 state = pr->throttling.state_count - duty_value; 686 } 687 688 pr->throttling.state = state; 689 690 local_irq_enable(); 691 692 acpi_handle_debug(pr->handle, 693 "Throttling state is T%d (%d%% throttling applied)\n", 694 state, pr->throttling.states[state].performance); 695 696 return 0; 697 } 698 699 #ifdef CONFIG_X86 700 static int acpi_throttling_rdmsr(u64 *value) 701 { 702 u64 msr_high, msr_low; 703 u64 msr = 0; 704 int ret = -1; 705 706 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || 707 !this_cpu_has(X86_FEATURE_ACPI)) { 708 pr_err("HARDWARE addr space,NOT supported yet\n"); 709 } else { 710 msr_low = 0; 711 msr_high = 0; 712 rdmsr_safe(MSR_IA32_THERM_CONTROL, 713 (u32 *)&msr_low, (u32 *) &msr_high); 714 msr = (msr_high << 32) | msr_low; 715 *value = (u64) msr; 716 ret = 0; 717 } 718 return ret; 719 } 720 721 static int acpi_throttling_wrmsr(u64 value) 722 { 723 int ret = -1; 724 u64 msr; 725 726 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || 727 !this_cpu_has(X86_FEATURE_ACPI)) { 728 pr_err("HARDWARE addr space,NOT supported yet\n"); 729 } else { 730 msr = value; 731 wrmsr_safe(MSR_IA32_THERM_CONTROL, 732 msr & 0xffffffff, msr >> 32); 733 ret = 0; 734 } 735 return ret; 736 } 737 #else 738 static int acpi_throttling_rdmsr(u64 *value) 739 { 740 pr_err("HARDWARE addr space,NOT supported yet\n"); 741 return -1; 742 } 743 744 static int acpi_throttling_wrmsr(u64 value) 745 { 746 pr_err("HARDWARE addr space,NOT supported yet\n"); 747 return -1; 748 } 749 #endif 750 751 static int acpi_read_throttling_status(struct acpi_processor *pr, 752 u64 *value) 753 { 754 u32 bit_width, bit_offset; 755 u32 ptc_value; 756 u64 ptc_mask; 757 struct acpi_processor_throttling *throttling; 758 int ret = -1; 759 760 throttling = &pr->throttling; 761 switch (throttling->status_register.space_id) { 762 case ACPI_ADR_SPACE_SYSTEM_IO: 763 bit_width = throttling->status_register.bit_width; 764 bit_offset = throttling->status_register.bit_offset; 765 766 acpi_os_read_port((acpi_io_address) throttling->status_register. 767 address, &ptc_value, 768 (u32) (bit_width + bit_offset)); 769 ptc_mask = (1 << bit_width) - 1; 770 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask); 771 ret = 0; 772 break; 773 case ACPI_ADR_SPACE_FIXED_HARDWARE: 774 ret = acpi_throttling_rdmsr(value); 775 break; 776 default: 777 pr_err("Unknown addr space %d\n", 778 (u32) (throttling->status_register.space_id)); 779 } 780 return ret; 781 } 782 783 static int acpi_write_throttling_state(struct acpi_processor *pr, 784 u64 value) 785 { 786 u32 bit_width, bit_offset; 787 u64 ptc_value; 788 u64 ptc_mask; 789 struct acpi_processor_throttling *throttling; 790 int ret = -1; 791 792 throttling = &pr->throttling; 793 switch (throttling->control_register.space_id) { 794 case ACPI_ADR_SPACE_SYSTEM_IO: 795 bit_width = throttling->control_register.bit_width; 796 bit_offset = throttling->control_register.bit_offset; 797 ptc_mask = (1 << bit_width) - 1; 798 ptc_value = value & ptc_mask; 799 800 acpi_os_write_port((acpi_io_address) throttling-> 801 control_register.address, 802 (u32) (ptc_value << bit_offset), 803 (u32) (bit_width + bit_offset)); 804 ret = 0; 805 break; 806 case ACPI_ADR_SPACE_FIXED_HARDWARE: 807 ret = acpi_throttling_wrmsr(value); 808 break; 809 default: 810 pr_err("Unknown addr space %d\n", 811 (u32) (throttling->control_register.space_id)); 812 } 813 return ret; 814 } 815 816 static int acpi_get_throttling_state(struct acpi_processor *pr, 817 u64 value) 818 { 819 int i; 820 821 for (i = 0; i < pr->throttling.state_count; i++) { 822 struct acpi_processor_tx_tss *tx = 823 (struct acpi_processor_tx_tss *)&(pr->throttling. 824 states_tss[i]); 825 if (tx->control == value) 826 return i; 827 } 828 return -1; 829 } 830 831 static int acpi_get_throttling_value(struct acpi_processor *pr, 832 int state, u64 *value) 833 { 834 int ret = -1; 835 836 if (state >= 0 && state <= pr->throttling.state_count) { 837 struct acpi_processor_tx_tss *tx = 838 (struct acpi_processor_tx_tss *)&(pr->throttling. 839 states_tss[state]); 840 *value = tx->control; 841 ret = 0; 842 } 843 return ret; 844 } 845 846 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) 847 { 848 int state = 0; 849 int ret; 850 u64 value; 851 852 if (!pr) 853 return -EINVAL; 854 855 if (!pr->flags.throttling) 856 return -ENODEV; 857 858 pr->throttling.state = 0; 859 860 value = 0; 861 ret = acpi_read_throttling_status(pr, &value); 862 if (ret >= 0) { 863 state = acpi_get_throttling_state(pr, value); 864 if (state == -1) { 865 acpi_handle_debug(pr->handle, 866 "Invalid throttling state, reset\n"); 867 state = 0; 868 ret = __acpi_processor_set_throttling(pr, state, true, 869 true); 870 if (ret) 871 return ret; 872 } 873 pr->throttling.state = state; 874 } 875 876 return 0; 877 } 878 879 static long __acpi_processor_get_throttling(void *data) 880 { 881 struct acpi_processor *pr = data; 882 883 return pr->throttling.acpi_processor_get_throttling(pr); 884 } 885 886 static int acpi_processor_get_throttling(struct acpi_processor *pr) 887 { 888 if (!pr) 889 return -EINVAL; 890 891 if (!pr->flags.throttling) 892 return -ENODEV; 893 894 /* 895 * This is either called from the CPU hotplug callback of 896 * processor_driver or via the ACPI probe function. In the latter 897 * case the CPU is not guaranteed to be online. Both call sites are 898 * protected against CPU hotplug. 899 */ 900 if (!cpu_online(pr->id)) 901 return -ENODEV; 902 903 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false); 904 } 905 906 static int acpi_processor_get_fadt_info(struct acpi_processor *pr) 907 { 908 int i, step; 909 910 if (!pr->throttling.address) { 911 acpi_handle_debug(pr->handle, "No throttling register\n"); 912 return -EINVAL; 913 } else if (!pr->throttling.duty_width) { 914 acpi_handle_debug(pr->handle, "No throttling states\n"); 915 return -EINVAL; 916 } 917 /* TBD: Support duty_cycle values that span bit 4. */ 918 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) { 919 pr_warn("duty_cycle spans bit 4\n"); 920 return -EINVAL; 921 } 922 923 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width; 924 925 /* 926 * Compute state values. Note that throttling displays a linear power 927 * performance relationship (at 50% performance the CPU will consume 928 * 50% power). Values are in 1/10th of a percent to preserve accuracy. 929 */ 930 931 step = (1000 / pr->throttling.state_count); 932 933 for (i = 0; i < pr->throttling.state_count; i++) { 934 pr->throttling.states[i].performance = 1000 - step * i; 935 pr->throttling.states[i].power = 1000 - step * i; 936 } 937 return 0; 938 } 939 940 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr, 941 int state, bool force) 942 { 943 u32 value = 0; 944 u32 duty_mask = 0; 945 u32 duty_value = 0; 946 947 if (!pr) 948 return -EINVAL; 949 950 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 951 return -EINVAL; 952 953 if (!pr->flags.throttling) 954 return -ENODEV; 955 956 if (!force && (state == pr->throttling.state)) 957 return 0; 958 959 if (state < pr->throttling_platform_limit) 960 return -EPERM; 961 /* 962 * Calculate the duty_value and duty_mask. 963 */ 964 if (state) { 965 duty_value = pr->throttling.state_count - state; 966 967 duty_value <<= pr->throttling.duty_offset; 968 969 /* Used to clear all duty_value bits */ 970 duty_mask = pr->throttling.state_count - 1; 971 972 duty_mask <<= acpi_gbl_FADT.duty_offset; 973 duty_mask = ~duty_mask; 974 } 975 976 local_irq_disable(); 977 978 /* 979 * Disable throttling by writing a 0 to bit 4. Note that we must 980 * turn it off before you can change the duty_value. 981 */ 982 value = inl(pr->throttling.address); 983 if (value & 0x10) { 984 value &= 0xFFFFFFEF; 985 outl(value, pr->throttling.address); 986 } 987 988 /* 989 * Write the new duty_value and then enable throttling. Note 990 * that a state value of 0 leaves throttling disabled. 991 */ 992 if (state) { 993 value &= duty_mask; 994 value |= duty_value; 995 outl(value, pr->throttling.address); 996 997 value |= 0x00000010; 998 outl(value, pr->throttling.address); 999 } 1000 1001 pr->throttling.state = state; 1002 1003 local_irq_enable(); 1004 1005 acpi_handle_debug(pr->handle, 1006 "Throttling state set to T%d (%d%%)\n", state, 1007 (pr->throttling.states[state].performance ? pr-> 1008 throttling.states[state].performance / 10 : 0)); 1009 1010 return 0; 1011 } 1012 1013 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, 1014 int state, bool force) 1015 { 1016 int ret; 1017 u64 value; 1018 1019 if (!pr) 1020 return -EINVAL; 1021 1022 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 1023 return -EINVAL; 1024 1025 if (!pr->flags.throttling) 1026 return -ENODEV; 1027 1028 if (!force && (state == pr->throttling.state)) 1029 return 0; 1030 1031 if (state < pr->throttling_platform_limit) 1032 return -EPERM; 1033 1034 value = 0; 1035 ret = acpi_get_throttling_value(pr, state, &value); 1036 if (ret >= 0) { 1037 acpi_write_throttling_state(pr, value); 1038 pr->throttling.state = state; 1039 } 1040 1041 return 0; 1042 } 1043 1044 static long acpi_processor_throttling_fn(void *data) 1045 { 1046 struct acpi_processor_throttling_arg *arg = data; 1047 struct acpi_processor *pr = arg->pr; 1048 1049 return pr->throttling.acpi_processor_set_throttling(pr, 1050 arg->target_state, arg->force); 1051 } 1052 1053 static int __acpi_processor_set_throttling(struct acpi_processor *pr, 1054 int state, bool force, bool direct) 1055 { 1056 int ret = 0; 1057 unsigned int i; 1058 struct acpi_processor *match_pr; 1059 struct acpi_processor_throttling *p_throttling; 1060 struct acpi_processor_throttling_arg arg; 1061 struct throttling_tstate t_state; 1062 1063 if (!pr) 1064 return -EINVAL; 1065 1066 if (!pr->flags.throttling) 1067 return -ENODEV; 1068 1069 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 1070 return -EINVAL; 1071 1072 if (cpu_is_offline(pr->id)) { 1073 /* 1074 * the cpu pointed by pr->id is offline. Unnecessary to change 1075 * the throttling state any more. 1076 */ 1077 return -ENODEV; 1078 } 1079 1080 t_state.target_state = state; 1081 p_throttling = &(pr->throttling); 1082 1083 /* 1084 * The throttling notifier will be called for every 1085 * affected cpu in order to get one proper T-state. 1086 * The notifier event is THROTTLING_PRECHANGE. 1087 */ 1088 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { 1089 t_state.cpu = i; 1090 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE, 1091 &t_state); 1092 } 1093 /* 1094 * The function of acpi_processor_set_throttling will be called 1095 * to switch T-state. If the coordination type is SW_ALL or HW_ALL, 1096 * it is necessary to call it for every affected cpu. Otherwise 1097 * it can be called only for the cpu pointed by pr. 1098 */ 1099 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) { 1100 arg.pr = pr; 1101 arg.target_state = state; 1102 arg.force = force; 1103 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg, 1104 direct); 1105 } else { 1106 /* 1107 * When the T-state coordination is SW_ALL or HW_ALL, 1108 * it is necessary to set T-state for every affected 1109 * cpus. 1110 */ 1111 for_each_cpu_and(i, cpu_online_mask, 1112 p_throttling->shared_cpu_map) { 1113 match_pr = per_cpu(processors, i); 1114 /* 1115 * If the pointer is invalid, we will report the 1116 * error message and continue. 1117 */ 1118 if (!match_pr) { 1119 acpi_handle_debug(pr->handle, 1120 "Invalid Pointer for CPU %d\n", i); 1121 continue; 1122 } 1123 /* 1124 * If the throttling control is unsupported on CPU i, 1125 * we will report the error message and continue. 1126 */ 1127 if (!match_pr->flags.throttling) { 1128 acpi_handle_debug(pr->handle, 1129 "Throttling Control unsupported on CPU %d\n", i); 1130 continue; 1131 } 1132 1133 arg.pr = match_pr; 1134 arg.target_state = state; 1135 arg.force = force; 1136 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, 1137 &arg, direct); 1138 } 1139 } 1140 /* 1141 * After the set_throttling is called, the 1142 * throttling notifier is called for every 1143 * affected cpu to update the T-states. 1144 * The notifier event is THROTTLING_POSTCHANGE 1145 */ 1146 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { 1147 t_state.cpu = i; 1148 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE, 1149 &t_state); 1150 } 1151 1152 return ret; 1153 } 1154 1155 int acpi_processor_set_throttling(struct acpi_processor *pr, int state, 1156 bool force) 1157 { 1158 return __acpi_processor_set_throttling(pr, state, force, false); 1159 } 1160 1161 int acpi_processor_get_throttling_info(struct acpi_processor *pr) 1162 { 1163 int result = 0; 1164 struct acpi_processor_throttling *pthrottling; 1165 1166 acpi_handle_debug(pr->handle, 1167 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n", 1168 pr->throttling.address, 1169 pr->throttling.duty_offset, 1170 pr->throttling.duty_width); 1171 1172 /* 1173 * Evaluate _PTC, _TSS and _TPC 1174 * They must all be present or none of them can be used. 1175 */ 1176 if (acpi_processor_get_throttling_control(pr) || 1177 acpi_processor_get_throttling_states(pr) || 1178 acpi_processor_get_platform_limit(pr)) { 1179 pr->throttling.acpi_processor_get_throttling = 1180 &acpi_processor_get_throttling_fadt; 1181 pr->throttling.acpi_processor_set_throttling = 1182 &acpi_processor_set_throttling_fadt; 1183 if (acpi_processor_get_fadt_info(pr)) 1184 return 0; 1185 } else { 1186 pr->throttling.acpi_processor_get_throttling = 1187 &acpi_processor_get_throttling_ptc; 1188 pr->throttling.acpi_processor_set_throttling = 1189 &acpi_processor_set_throttling_ptc; 1190 } 1191 1192 /* 1193 * If TSD package for one CPU can't be parsed successfully, it means 1194 * that this CPU will have no coordination with other CPUs. 1195 */ 1196 if (acpi_processor_get_tsd(pr)) { 1197 pthrottling = &pr->throttling; 1198 pthrottling->tsd_valid_flag = 0; 1199 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); 1200 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 1201 } 1202 1203 /* 1204 * PIIX4 Errata: We don't support throttling on the original PIIX4. 1205 * This shouldn't be an issue as few (if any) mobile systems ever 1206 * used this part. 1207 */ 1208 if (errata.piix4.throttle) { 1209 acpi_handle_debug(pr->handle, 1210 "Throttling not supported on PIIX4 A- or B-step\n"); 1211 return 0; 1212 } 1213 1214 acpi_handle_debug(pr->handle, "Found %d throttling states\n", 1215 pr->throttling.state_count); 1216 1217 pr->flags.throttling = 1; 1218 1219 /* 1220 * Disable throttling (if enabled). We'll let subsequent policy (e.g. 1221 * thermal) decide to lower performance if it so chooses, but for now 1222 * we'll crank up the speed. 1223 */ 1224 1225 result = acpi_processor_get_throttling(pr); 1226 if (result) 1227 goto end; 1228 1229 if (pr->throttling.state) { 1230 acpi_handle_debug(pr->handle, 1231 "Disabling throttling (was T%d)\n", 1232 pr->throttling.state); 1233 result = acpi_processor_set_throttling(pr, 0, false); 1234 if (result) 1235 goto end; 1236 } 1237 1238 end: 1239 if (result) 1240 pr->flags.throttling = 0; 1241 1242 return result; 1243 } 1244 1245