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