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 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/slab.h> 15 #include <linux/init.h> 16 #include <linux/sched.h> 17 #include <linux/cpufreq.h> 18 #include <linux/acpi.h> 19 #include <acpi/processor.h> 20 #include <asm/io.h> 21 #include <linux/uaccess.h> 22 23 #define PREFIX "ACPI: " 24 25 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 26 ACPI_MODULE_NAME("processor_throttling"); 27 28 /* ignore_tpc: 29 * 0 -> acpi processor driver doesn't ignore _TPC values 30 * 1 -> acpi processor driver ignores _TPC values 31 */ 32 static int ignore_tpc; 33 module_param(ignore_tpc, int, 0644); 34 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support"); 35 36 struct throttling_tstate { 37 unsigned int cpu; /* cpu nr */ 38 int target_state; /* target T-state */ 39 }; 40 41 struct acpi_processor_throttling_arg { 42 struct acpi_processor *pr; 43 int target_state; 44 bool force; 45 }; 46 47 #define THROTTLING_PRECHANGE (1) 48 #define THROTTLING_POSTCHANGE (2) 49 50 static int acpi_processor_get_throttling(struct acpi_processor *pr); 51 static int __acpi_processor_set_throttling(struct acpi_processor *pr, 52 int state, bool force, bool direct); 53 54 static int acpi_processor_update_tsd_coord(void) 55 { 56 int count, count_target; 57 int retval = 0; 58 unsigned int i, j; 59 cpumask_var_t covered_cpus; 60 struct acpi_processor *pr, *match_pr; 61 struct acpi_tsd_package *pdomain, *match_pdomain; 62 struct acpi_processor_throttling *pthrottling, *match_pthrottling; 63 64 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) 65 return -ENOMEM; 66 67 /* 68 * Now that we have _TSD data from all CPUs, lets setup T-state 69 * coordination between all CPUs. 70 */ 71 for_each_possible_cpu(i) { 72 pr = per_cpu(processors, i); 73 if (!pr) 74 continue; 75 76 /* Basic validity check for domain info */ 77 pthrottling = &(pr->throttling); 78 79 /* 80 * If tsd package for one cpu is invalid, the coordination 81 * among all CPUs is thought as invalid. 82 * Maybe it is ugly. 83 */ 84 if (!pthrottling->tsd_valid_flag) { 85 retval = -EINVAL; 86 break; 87 } 88 } 89 if (retval) 90 goto err_ret; 91 92 for_each_possible_cpu(i) { 93 pr = per_cpu(processors, i); 94 if (!pr) 95 continue; 96 97 if (cpumask_test_cpu(i, covered_cpus)) 98 continue; 99 pthrottling = &pr->throttling; 100 101 pdomain = &(pthrottling->domain_info); 102 cpumask_set_cpu(i, pthrottling->shared_cpu_map); 103 cpumask_set_cpu(i, covered_cpus); 104 /* 105 * If the number of processor in the TSD domain is 1, it is 106 * unnecessary to parse the coordination for this CPU. 107 */ 108 if (pdomain->num_processors <= 1) 109 continue; 110 111 /* Validate the Domain info */ 112 count_target = pdomain->num_processors; 113 count = 1; 114 115 for_each_possible_cpu(j) { 116 if (i == j) 117 continue; 118 119 match_pr = per_cpu(processors, j); 120 if (!match_pr) 121 continue; 122 123 match_pthrottling = &(match_pr->throttling); 124 match_pdomain = &(match_pthrottling->domain_info); 125 if (match_pdomain->domain != pdomain->domain) 126 continue; 127 128 /* Here i and j are in the same domain. 129 * If two TSD packages have the same domain, they 130 * should have the same num_porcessors and 131 * coordination type. Otherwise it will be regarded 132 * as illegal. 133 */ 134 if (match_pdomain->num_processors != count_target) { 135 retval = -EINVAL; 136 goto err_ret; 137 } 138 139 if (pdomain->coord_type != match_pdomain->coord_type) { 140 retval = -EINVAL; 141 goto err_ret; 142 } 143 144 cpumask_set_cpu(j, covered_cpus); 145 cpumask_set_cpu(j, pthrottling->shared_cpu_map); 146 count++; 147 } 148 for_each_possible_cpu(j) { 149 if (i == j) 150 continue; 151 152 match_pr = per_cpu(processors, j); 153 if (!match_pr) 154 continue; 155 156 match_pthrottling = &(match_pr->throttling); 157 match_pdomain = &(match_pthrottling->domain_info); 158 if (match_pdomain->domain != pdomain->domain) 159 continue; 160 161 /* 162 * If some CPUS have the same domain, they 163 * will have the same shared_cpu_map. 164 */ 165 cpumask_copy(match_pthrottling->shared_cpu_map, 166 pthrottling->shared_cpu_map); 167 } 168 } 169 170 err_ret: 171 free_cpumask_var(covered_cpus); 172 173 for_each_possible_cpu(i) { 174 pr = per_cpu(processors, i); 175 if (!pr) 176 continue; 177 178 /* 179 * Assume no coordination on any error parsing domain info. 180 * The coordination type will be forced as SW_ALL. 181 */ 182 if (retval) { 183 pthrottling = &(pr->throttling); 184 cpumask_clear(pthrottling->shared_cpu_map); 185 cpumask_set_cpu(i, pthrottling->shared_cpu_map); 186 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 187 } 188 } 189 190 return retval; 191 } 192 193 /* 194 * Update the T-state coordination after the _TSD 195 * data for all cpus is obtained. 196 */ 197 void acpi_processor_throttling_init(void) 198 { 199 if (acpi_processor_update_tsd_coord()) { 200 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 201 "Assume no T-state coordination\n")); 202 } 203 204 return; 205 } 206 207 static int acpi_processor_throttling_notifier(unsigned long event, void *data) 208 { 209 struct throttling_tstate *p_tstate = data; 210 struct acpi_processor *pr; 211 unsigned int cpu ; 212 int target_state; 213 struct acpi_processor_limit *p_limit; 214 struct acpi_processor_throttling *p_throttling; 215 216 cpu = p_tstate->cpu; 217 pr = per_cpu(processors, cpu); 218 if (!pr) { 219 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n")); 220 return 0; 221 } 222 if (!pr->flags.throttling) { 223 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is " 224 "unsupported on CPU %d\n", cpu)); 225 return 0; 226 } 227 target_state = p_tstate->target_state; 228 p_throttling = &(pr->throttling); 229 switch (event) { 230 case THROTTLING_PRECHANGE: 231 /* 232 * Prechange event is used to choose one proper t-state, 233 * which meets the limits of thermal, user and _TPC. 234 */ 235 p_limit = &pr->limit; 236 if (p_limit->thermal.tx > target_state) 237 target_state = p_limit->thermal.tx; 238 if (p_limit->user.tx > target_state) 239 target_state = p_limit->user.tx; 240 if (pr->throttling_platform_limit > target_state) 241 target_state = pr->throttling_platform_limit; 242 if (target_state >= p_throttling->state_count) { 243 printk(KERN_WARNING 244 "Exceed the limit of T-state \n"); 245 target_state = p_throttling->state_count - 1; 246 } 247 p_tstate->target_state = target_state; 248 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:" 249 "target T-state of CPU %d is T%d\n", 250 cpu, target_state)); 251 break; 252 case THROTTLING_POSTCHANGE: 253 /* 254 * Postchange event is only used to update the 255 * T-state flag of acpi_processor_throttling. 256 */ 257 p_throttling->state = target_state; 258 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:" 259 "CPU %d is switched to T%d\n", 260 cpu, target_state)); 261 break; 262 default: 263 printk(KERN_WARNING 264 "Unsupported Throttling notifier event\n"); 265 break; 266 } 267 268 return 0; 269 } 270 271 /* 272 * _TPC - Throttling Present Capabilities 273 */ 274 static int acpi_processor_get_platform_limit(struct acpi_processor *pr) 275 { 276 acpi_status status = 0; 277 unsigned long long tpc = 0; 278 279 if (!pr) 280 return -EINVAL; 281 282 if (ignore_tpc) 283 goto end; 284 285 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc); 286 if (ACPI_FAILURE(status)) { 287 if (status != AE_NOT_FOUND) { 288 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC")); 289 } 290 return -ENODEV; 291 } 292 293 end: 294 pr->throttling_platform_limit = (int)tpc; 295 return 0; 296 } 297 298 int acpi_processor_tstate_has_changed(struct acpi_processor *pr) 299 { 300 int result = 0; 301 int throttling_limit; 302 int current_state; 303 struct acpi_processor_limit *limit; 304 int target_state; 305 306 if (ignore_tpc) 307 return 0; 308 309 result = acpi_processor_get_platform_limit(pr); 310 if (result) { 311 /* Throttling Limit is unsupported */ 312 return result; 313 } 314 315 throttling_limit = pr->throttling_platform_limit; 316 if (throttling_limit >= pr->throttling.state_count) { 317 /* Uncorrect Throttling Limit */ 318 return -EINVAL; 319 } 320 321 current_state = pr->throttling.state; 322 if (current_state > throttling_limit) { 323 /* 324 * The current state can meet the requirement of 325 * _TPC limit. But it is reasonable that OSPM changes 326 * t-states from high to low for better performance. 327 * Of course the limit condition of thermal 328 * and user should be considered. 329 */ 330 limit = &pr->limit; 331 target_state = throttling_limit; 332 if (limit->thermal.tx > target_state) 333 target_state = limit->thermal.tx; 334 if (limit->user.tx > target_state) 335 target_state = limit->user.tx; 336 } else if (current_state == throttling_limit) { 337 /* 338 * Unnecessary to change the throttling state 339 */ 340 return 0; 341 } else { 342 /* 343 * If the current state is lower than the limit of _TPC, it 344 * will be forced to switch to the throttling state defined 345 * by throttling_platfor_limit. 346 * Because the previous state meets with the limit condition 347 * of thermal and user, it is unnecessary to check it again. 348 */ 349 target_state = throttling_limit; 350 } 351 return acpi_processor_set_throttling(pr, target_state, false); 352 } 353 354 /* 355 * This function is used to reevaluate whether the T-state is valid 356 * after one CPU is onlined/offlined. 357 * It is noted that it won't reevaluate the following properties for 358 * the T-state. 359 * 1. Control method. 360 * 2. the number of supported T-state 361 * 3. TSD domain 362 */ 363 void acpi_processor_reevaluate_tstate(struct acpi_processor *pr, 364 bool is_dead) 365 { 366 int result = 0; 367 368 if (is_dead) { 369 /* When one CPU is offline, the T-state throttling 370 * will be invalidated. 371 */ 372 pr->flags.throttling = 0; 373 return; 374 } 375 /* the following is to recheck whether the T-state is valid for 376 * the online CPU 377 */ 378 if (!pr->throttling.state_count) { 379 /* If the number of T-state is invalid, it is 380 * invalidated. 381 */ 382 pr->flags.throttling = 0; 383 return; 384 } 385 pr->flags.throttling = 1; 386 387 /* Disable throttling (if enabled). We'll let subsequent 388 * policy (e.g.thermal) decide to lower performance if it 389 * so chooses, but for now we'll crank up the speed. 390 */ 391 392 result = acpi_processor_get_throttling(pr); 393 if (result) 394 goto end; 395 396 if (pr->throttling.state) { 397 result = acpi_processor_set_throttling(pr, 0, false); 398 if (result) 399 goto end; 400 } 401 402 end: 403 if (result) 404 pr->flags.throttling = 0; 405 } 406 /* 407 * _PTC - Processor Throttling Control (and status) register location 408 */ 409 static int acpi_processor_get_throttling_control(struct acpi_processor *pr) 410 { 411 int result = 0; 412 acpi_status status = 0; 413 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 414 union acpi_object *ptc = NULL; 415 union acpi_object obj = { 0 }; 416 struct acpi_processor_throttling *throttling; 417 418 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer); 419 if (ACPI_FAILURE(status)) { 420 if (status != AE_NOT_FOUND) { 421 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC")); 422 } 423 return -ENODEV; 424 } 425 426 ptc = (union acpi_object *)buffer.pointer; 427 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE) 428 || (ptc->package.count != 2)) { 429 printk(KERN_ERR PREFIX "Invalid _PTC data\n"); 430 result = -EFAULT; 431 goto end; 432 } 433 434 /* 435 * control_register 436 */ 437 438 obj = ptc->package.elements[0]; 439 440 if ((obj.type != ACPI_TYPE_BUFFER) 441 || (obj.buffer.length < sizeof(struct acpi_ptc_register)) 442 || (obj.buffer.pointer == NULL)) { 443 printk(KERN_ERR PREFIX 444 "Invalid _PTC data (control_register)\n"); 445 result = -EFAULT; 446 goto end; 447 } 448 memcpy(&pr->throttling.control_register, obj.buffer.pointer, 449 sizeof(struct acpi_ptc_register)); 450 451 /* 452 * status_register 453 */ 454 455 obj = ptc->package.elements[1]; 456 457 if ((obj.type != ACPI_TYPE_BUFFER) 458 || (obj.buffer.length < sizeof(struct acpi_ptc_register)) 459 || (obj.buffer.pointer == NULL)) { 460 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n"); 461 result = -EFAULT; 462 goto end; 463 } 464 465 memcpy(&pr->throttling.status_register, obj.buffer.pointer, 466 sizeof(struct acpi_ptc_register)); 467 468 throttling = &pr->throttling; 469 470 if ((throttling->control_register.bit_width + 471 throttling->control_register.bit_offset) > 32) { 472 printk(KERN_ERR PREFIX "Invalid _PTC control register\n"); 473 result = -EFAULT; 474 goto end; 475 } 476 477 if ((throttling->status_register.bit_width + 478 throttling->status_register.bit_offset) > 32) { 479 printk(KERN_ERR PREFIX "Invalid _PTC status register\n"); 480 result = -EFAULT; 481 goto end; 482 } 483 484 end: 485 kfree(buffer.pointer); 486 487 return result; 488 } 489 490 /* 491 * _TSS - Throttling Supported States 492 */ 493 static int acpi_processor_get_throttling_states(struct acpi_processor *pr) 494 { 495 int result = 0; 496 acpi_status status = AE_OK; 497 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 498 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" }; 499 struct acpi_buffer state = { 0, NULL }; 500 union acpi_object *tss = NULL; 501 int i; 502 503 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer); 504 if (ACPI_FAILURE(status)) { 505 if (status != AE_NOT_FOUND) { 506 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS")); 507 } 508 return -ENODEV; 509 } 510 511 tss = buffer.pointer; 512 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) { 513 printk(KERN_ERR PREFIX "Invalid _TSS data\n"); 514 result = -EFAULT; 515 goto end; 516 } 517 518 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n", 519 tss->package.count)); 520 521 pr->throttling.state_count = tss->package.count; 522 pr->throttling.states_tss = 523 kmalloc_array(tss->package.count, 524 sizeof(struct acpi_processor_tx_tss), 525 GFP_KERNEL); 526 if (!pr->throttling.states_tss) { 527 result = -ENOMEM; 528 goto end; 529 } 530 531 for (i = 0; i < pr->throttling.state_count; i++) { 532 533 struct acpi_processor_tx_tss *tx = 534 (struct acpi_processor_tx_tss *)&(pr->throttling. 535 states_tss[i]); 536 537 state.length = sizeof(struct acpi_processor_tx_tss); 538 state.pointer = tx; 539 540 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i)); 541 542 status = acpi_extract_package(&(tss->package.elements[i]), 543 &format, &state); 544 if (ACPI_FAILURE(status)) { 545 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data")); 546 result = -EFAULT; 547 kfree(pr->throttling.states_tss); 548 goto end; 549 } 550 551 if (!tx->freqpercentage) { 552 printk(KERN_ERR PREFIX 553 "Invalid _TSS data: freq is zero\n"); 554 result = -EFAULT; 555 kfree(pr->throttling.states_tss); 556 goto end; 557 } 558 } 559 560 end: 561 kfree(buffer.pointer); 562 563 return result; 564 } 565 566 /* 567 * _TSD - T-State Dependencies 568 */ 569 static int acpi_processor_get_tsd(struct acpi_processor *pr) 570 { 571 int result = 0; 572 acpi_status status = AE_OK; 573 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 574 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" }; 575 struct acpi_buffer state = { 0, NULL }; 576 union acpi_object *tsd = NULL; 577 struct acpi_tsd_package *pdomain; 578 struct acpi_processor_throttling *pthrottling; 579 580 pthrottling = &pr->throttling; 581 pthrottling->tsd_valid_flag = 0; 582 583 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer); 584 if (ACPI_FAILURE(status)) { 585 if (status != AE_NOT_FOUND) { 586 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD")); 587 } 588 return -ENODEV; 589 } 590 591 tsd = buffer.pointer; 592 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) { 593 printk(KERN_ERR PREFIX "Invalid _TSD data\n"); 594 result = -EFAULT; 595 goto end; 596 } 597 598 if (tsd->package.count != 1) { 599 printk(KERN_ERR PREFIX "Invalid _TSD data\n"); 600 result = -EFAULT; 601 goto end; 602 } 603 604 pdomain = &(pr->throttling.domain_info); 605 606 state.length = sizeof(struct acpi_tsd_package); 607 state.pointer = pdomain; 608 609 status = acpi_extract_package(&(tsd->package.elements[0]), 610 &format, &state); 611 if (ACPI_FAILURE(status)) { 612 printk(KERN_ERR PREFIX "Invalid _TSD data\n"); 613 result = -EFAULT; 614 goto end; 615 } 616 617 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) { 618 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n"); 619 result = -EFAULT; 620 goto end; 621 } 622 623 if (pdomain->revision != ACPI_TSD_REV0_REVISION) { 624 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n"); 625 result = -EFAULT; 626 goto end; 627 } 628 629 pthrottling = &pr->throttling; 630 pthrottling->tsd_valid_flag = 1; 631 pthrottling->shared_type = pdomain->coord_type; 632 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); 633 /* 634 * If the coordination type is not defined in ACPI spec, 635 * the tsd_valid_flag will be clear and coordination type 636 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL. 637 */ 638 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && 639 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && 640 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { 641 pthrottling->tsd_valid_flag = 0; 642 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 643 } 644 645 end: 646 kfree(buffer.pointer); 647 return result; 648 } 649 650 /* -------------------------------------------------------------------------- 651 Throttling Control 652 -------------------------------------------------------------------------- */ 653 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr) 654 { 655 int state = 0; 656 u32 value = 0; 657 u32 duty_mask = 0; 658 u32 duty_value = 0; 659 660 if (!pr) 661 return -EINVAL; 662 663 if (!pr->flags.throttling) 664 return -ENODEV; 665 666 /* 667 * We don't care about error returns - we just try to mark 668 * these reserved so that nobody else is confused into thinking 669 * that this region might be unused.. 670 * 671 * (In particular, allocating the IO range for Cardbus) 672 */ 673 request_region(pr->throttling.address, 6, "ACPI CPU throttle"); 674 675 pr->throttling.state = 0; 676 677 duty_mask = pr->throttling.state_count - 1; 678 679 duty_mask <<= pr->throttling.duty_offset; 680 681 local_irq_disable(); 682 683 value = inl(pr->throttling.address); 684 685 /* 686 * Compute the current throttling state when throttling is enabled 687 * (bit 4 is on). 688 */ 689 if (value & 0x10) { 690 duty_value = value & duty_mask; 691 duty_value >>= pr->throttling.duty_offset; 692 693 if (duty_value) 694 state = pr->throttling.state_count - duty_value; 695 } 696 697 pr->throttling.state = state; 698 699 local_irq_enable(); 700 701 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 702 "Throttling state is T%d (%d%% throttling applied)\n", 703 state, pr->throttling.states[state].performance)); 704 705 return 0; 706 } 707 708 #ifdef CONFIG_X86 709 static int acpi_throttling_rdmsr(u64 *value) 710 { 711 u64 msr_high, msr_low; 712 u64 msr = 0; 713 int ret = -1; 714 715 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || 716 !this_cpu_has(X86_FEATURE_ACPI)) { 717 printk(KERN_ERR PREFIX 718 "HARDWARE addr space,NOT supported yet\n"); 719 } else { 720 msr_low = 0; 721 msr_high = 0; 722 rdmsr_safe(MSR_IA32_THERM_CONTROL, 723 (u32 *)&msr_low , (u32 *) &msr_high); 724 msr = (msr_high << 32) | msr_low; 725 *value = (u64) msr; 726 ret = 0; 727 } 728 return ret; 729 } 730 731 static int acpi_throttling_wrmsr(u64 value) 732 { 733 int ret = -1; 734 u64 msr; 735 736 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || 737 !this_cpu_has(X86_FEATURE_ACPI)) { 738 printk(KERN_ERR PREFIX 739 "HARDWARE addr space,NOT supported yet\n"); 740 } else { 741 msr = value; 742 wrmsr_safe(MSR_IA32_THERM_CONTROL, 743 msr & 0xffffffff, msr >> 32); 744 ret = 0; 745 } 746 return ret; 747 } 748 #else 749 static int acpi_throttling_rdmsr(u64 *value) 750 { 751 printk(KERN_ERR PREFIX 752 "HARDWARE addr space,NOT supported yet\n"); 753 return -1; 754 } 755 756 static int acpi_throttling_wrmsr(u64 value) 757 { 758 printk(KERN_ERR PREFIX 759 "HARDWARE addr space,NOT supported yet\n"); 760 return -1; 761 } 762 #endif 763 764 static int acpi_read_throttling_status(struct acpi_processor *pr, 765 u64 *value) 766 { 767 u32 bit_width, bit_offset; 768 u32 ptc_value; 769 u64 ptc_mask; 770 struct acpi_processor_throttling *throttling; 771 int ret = -1; 772 773 throttling = &pr->throttling; 774 switch (throttling->status_register.space_id) { 775 case ACPI_ADR_SPACE_SYSTEM_IO: 776 bit_width = throttling->status_register.bit_width; 777 bit_offset = throttling->status_register.bit_offset; 778 779 acpi_os_read_port((acpi_io_address) throttling->status_register. 780 address, &ptc_value, 781 (u32) (bit_width + bit_offset)); 782 ptc_mask = (1 << bit_width) - 1; 783 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask); 784 ret = 0; 785 break; 786 case ACPI_ADR_SPACE_FIXED_HARDWARE: 787 ret = acpi_throttling_rdmsr(value); 788 break; 789 default: 790 printk(KERN_ERR PREFIX "Unknown addr space %d\n", 791 (u32) (throttling->status_register.space_id)); 792 } 793 return ret; 794 } 795 796 static int acpi_write_throttling_state(struct acpi_processor *pr, 797 u64 value) 798 { 799 u32 bit_width, bit_offset; 800 u64 ptc_value; 801 u64 ptc_mask; 802 struct acpi_processor_throttling *throttling; 803 int ret = -1; 804 805 throttling = &pr->throttling; 806 switch (throttling->control_register.space_id) { 807 case ACPI_ADR_SPACE_SYSTEM_IO: 808 bit_width = throttling->control_register.bit_width; 809 bit_offset = throttling->control_register.bit_offset; 810 ptc_mask = (1 << bit_width) - 1; 811 ptc_value = value & ptc_mask; 812 813 acpi_os_write_port((acpi_io_address) throttling-> 814 control_register.address, 815 (u32) (ptc_value << bit_offset), 816 (u32) (bit_width + bit_offset)); 817 ret = 0; 818 break; 819 case ACPI_ADR_SPACE_FIXED_HARDWARE: 820 ret = acpi_throttling_wrmsr(value); 821 break; 822 default: 823 printk(KERN_ERR PREFIX "Unknown addr space %d\n", 824 (u32) (throttling->control_register.space_id)); 825 } 826 return ret; 827 } 828 829 static int acpi_get_throttling_state(struct acpi_processor *pr, 830 u64 value) 831 { 832 int i; 833 834 for (i = 0; i < pr->throttling.state_count; i++) { 835 struct acpi_processor_tx_tss *tx = 836 (struct acpi_processor_tx_tss *)&(pr->throttling. 837 states_tss[i]); 838 if (tx->control == value) 839 return i; 840 } 841 return -1; 842 } 843 844 static int acpi_get_throttling_value(struct acpi_processor *pr, 845 int state, u64 *value) 846 { 847 int ret = -1; 848 849 if (state >= 0 && state <= pr->throttling.state_count) { 850 struct acpi_processor_tx_tss *tx = 851 (struct acpi_processor_tx_tss *)&(pr->throttling. 852 states_tss[state]); 853 *value = tx->control; 854 ret = 0; 855 } 856 return ret; 857 } 858 859 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) 860 { 861 int state = 0; 862 int ret; 863 u64 value; 864 865 if (!pr) 866 return -EINVAL; 867 868 if (!pr->flags.throttling) 869 return -ENODEV; 870 871 pr->throttling.state = 0; 872 873 value = 0; 874 ret = acpi_read_throttling_status(pr, &value); 875 if (ret >= 0) { 876 state = acpi_get_throttling_state(pr, value); 877 if (state == -1) { 878 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 879 "Invalid throttling state, reset\n")); 880 state = 0; 881 ret = __acpi_processor_set_throttling(pr, state, true, 882 true); 883 if (ret) 884 return ret; 885 } 886 pr->throttling.state = state; 887 } 888 889 return 0; 890 } 891 892 static long __acpi_processor_get_throttling(void *data) 893 { 894 struct acpi_processor *pr = data; 895 896 return pr->throttling.acpi_processor_get_throttling(pr); 897 } 898 899 static int acpi_processor_get_throttling(struct acpi_processor *pr) 900 { 901 if (!pr) 902 return -EINVAL; 903 904 if (!pr->flags.throttling) 905 return -ENODEV; 906 907 /* 908 * This is either called from the CPU hotplug callback of 909 * processor_driver or via the ACPI probe function. In the latter 910 * case the CPU is not guaranteed to be online. Both call sites are 911 * protected against CPU hotplug. 912 */ 913 if (!cpu_online(pr->id)) 914 return -ENODEV; 915 916 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false); 917 } 918 919 static int acpi_processor_get_fadt_info(struct acpi_processor *pr) 920 { 921 int i, step; 922 923 if (!pr->throttling.address) { 924 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n")); 925 return -EINVAL; 926 } else if (!pr->throttling.duty_width) { 927 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n")); 928 return -EINVAL; 929 } 930 /* TBD: Support duty_cycle values that span bit 4. */ 931 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) { 932 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n"); 933 return -EINVAL; 934 } 935 936 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width; 937 938 /* 939 * Compute state values. Note that throttling displays a linear power 940 * performance relationship (at 50% performance the CPU will consume 941 * 50% power). Values are in 1/10th of a percent to preserve accuracy. 942 */ 943 944 step = (1000 / pr->throttling.state_count); 945 946 for (i = 0; i < pr->throttling.state_count; i++) { 947 pr->throttling.states[i].performance = 1000 - step * i; 948 pr->throttling.states[i].power = 1000 - step * i; 949 } 950 return 0; 951 } 952 953 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr, 954 int state, bool force) 955 { 956 u32 value = 0; 957 u32 duty_mask = 0; 958 u32 duty_value = 0; 959 960 if (!pr) 961 return -EINVAL; 962 963 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 964 return -EINVAL; 965 966 if (!pr->flags.throttling) 967 return -ENODEV; 968 969 if (!force && (state == pr->throttling.state)) 970 return 0; 971 972 if (state < pr->throttling_platform_limit) 973 return -EPERM; 974 /* 975 * Calculate the duty_value and duty_mask. 976 */ 977 if (state) { 978 duty_value = pr->throttling.state_count - state; 979 980 duty_value <<= pr->throttling.duty_offset; 981 982 /* Used to clear all duty_value bits */ 983 duty_mask = pr->throttling.state_count - 1; 984 985 duty_mask <<= acpi_gbl_FADT.duty_offset; 986 duty_mask = ~duty_mask; 987 } 988 989 local_irq_disable(); 990 991 /* 992 * Disable throttling by writing a 0 to bit 4. Note that we must 993 * turn it off before you can change the duty_value. 994 */ 995 value = inl(pr->throttling.address); 996 if (value & 0x10) { 997 value &= 0xFFFFFFEF; 998 outl(value, pr->throttling.address); 999 } 1000 1001 /* 1002 * Write the new duty_value and then enable throttling. Note 1003 * that a state value of 0 leaves throttling disabled. 1004 */ 1005 if (state) { 1006 value &= duty_mask; 1007 value |= duty_value; 1008 outl(value, pr->throttling.address); 1009 1010 value |= 0x00000010; 1011 outl(value, pr->throttling.address); 1012 } 1013 1014 pr->throttling.state = state; 1015 1016 local_irq_enable(); 1017 1018 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1019 "Throttling state set to T%d (%d%%)\n", state, 1020 (pr->throttling.states[state].performance ? pr-> 1021 throttling.states[state].performance / 10 : 0))); 1022 1023 return 0; 1024 } 1025 1026 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, 1027 int state, bool force) 1028 { 1029 int ret; 1030 u64 value; 1031 1032 if (!pr) 1033 return -EINVAL; 1034 1035 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 1036 return -EINVAL; 1037 1038 if (!pr->flags.throttling) 1039 return -ENODEV; 1040 1041 if (!force && (state == pr->throttling.state)) 1042 return 0; 1043 1044 if (state < pr->throttling_platform_limit) 1045 return -EPERM; 1046 1047 value = 0; 1048 ret = acpi_get_throttling_value(pr, state, &value); 1049 if (ret >= 0) { 1050 acpi_write_throttling_state(pr, value); 1051 pr->throttling.state = state; 1052 } 1053 1054 return 0; 1055 } 1056 1057 static long acpi_processor_throttling_fn(void *data) 1058 { 1059 struct acpi_processor_throttling_arg *arg = data; 1060 struct acpi_processor *pr = arg->pr; 1061 1062 return pr->throttling.acpi_processor_set_throttling(pr, 1063 arg->target_state, arg->force); 1064 } 1065 1066 static int __acpi_processor_set_throttling(struct acpi_processor *pr, 1067 int state, bool force, bool direct) 1068 { 1069 int ret = 0; 1070 unsigned int i; 1071 struct acpi_processor *match_pr; 1072 struct acpi_processor_throttling *p_throttling; 1073 struct acpi_processor_throttling_arg arg; 1074 struct throttling_tstate t_state; 1075 1076 if (!pr) 1077 return -EINVAL; 1078 1079 if (!pr->flags.throttling) 1080 return -ENODEV; 1081 1082 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 1083 return -EINVAL; 1084 1085 if (cpu_is_offline(pr->id)) { 1086 /* 1087 * the cpu pointed by pr->id is offline. Unnecessary to change 1088 * the throttling state any more. 1089 */ 1090 return -ENODEV; 1091 } 1092 1093 t_state.target_state = state; 1094 p_throttling = &(pr->throttling); 1095 1096 /* 1097 * The throttling notifier will be called for every 1098 * affected cpu in order to get one proper T-state. 1099 * The notifier event is THROTTLING_PRECHANGE. 1100 */ 1101 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { 1102 t_state.cpu = i; 1103 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE, 1104 &t_state); 1105 } 1106 /* 1107 * The function of acpi_processor_set_throttling will be called 1108 * to switch T-state. If the coordination type is SW_ALL or HW_ALL, 1109 * it is necessary to call it for every affected cpu. Otherwise 1110 * it can be called only for the cpu pointed by pr. 1111 */ 1112 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) { 1113 arg.pr = pr; 1114 arg.target_state = state; 1115 arg.force = force; 1116 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg, 1117 direct); 1118 } else { 1119 /* 1120 * When the T-state coordination is SW_ALL or HW_ALL, 1121 * it is necessary to set T-state for every affected 1122 * cpus. 1123 */ 1124 for_each_cpu_and(i, cpu_online_mask, 1125 p_throttling->shared_cpu_map) { 1126 match_pr = per_cpu(processors, i); 1127 /* 1128 * If the pointer is invalid, we will report the 1129 * error message and continue. 1130 */ 1131 if (!match_pr) { 1132 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1133 "Invalid Pointer for CPU %d\n", i)); 1134 continue; 1135 } 1136 /* 1137 * If the throttling control is unsupported on CPU i, 1138 * we will report the error message and continue. 1139 */ 1140 if (!match_pr->flags.throttling) { 1141 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1142 "Throttling Control is unsupported " 1143 "on CPU %d\n", i)); 1144 continue; 1145 } 1146 1147 arg.pr = match_pr; 1148 arg.target_state = state; 1149 arg.force = force; 1150 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, 1151 &arg, direct); 1152 } 1153 } 1154 /* 1155 * After the set_throttling is called, the 1156 * throttling notifier is called for every 1157 * affected cpu to update the T-states. 1158 * The notifier event is THROTTLING_POSTCHANGE 1159 */ 1160 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { 1161 t_state.cpu = i; 1162 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE, 1163 &t_state); 1164 } 1165 1166 return ret; 1167 } 1168 1169 int acpi_processor_set_throttling(struct acpi_processor *pr, int state, 1170 bool force) 1171 { 1172 return __acpi_processor_set_throttling(pr, state, force, false); 1173 } 1174 1175 int acpi_processor_get_throttling_info(struct acpi_processor *pr) 1176 { 1177 int result = 0; 1178 struct acpi_processor_throttling *pthrottling; 1179 1180 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1181 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n", 1182 pr->throttling.address, 1183 pr->throttling.duty_offset, 1184 pr->throttling.duty_width)); 1185 1186 /* 1187 * Evaluate _PTC, _TSS and _TPC 1188 * They must all be present or none of them can be used. 1189 */ 1190 if (acpi_processor_get_throttling_control(pr) || 1191 acpi_processor_get_throttling_states(pr) || 1192 acpi_processor_get_platform_limit(pr)) 1193 { 1194 pr->throttling.acpi_processor_get_throttling = 1195 &acpi_processor_get_throttling_fadt; 1196 pr->throttling.acpi_processor_set_throttling = 1197 &acpi_processor_set_throttling_fadt; 1198 if (acpi_processor_get_fadt_info(pr)) 1199 return 0; 1200 } else { 1201 pr->throttling.acpi_processor_get_throttling = 1202 &acpi_processor_get_throttling_ptc; 1203 pr->throttling.acpi_processor_set_throttling = 1204 &acpi_processor_set_throttling_ptc; 1205 } 1206 1207 /* 1208 * If TSD package for one CPU can't be parsed successfully, it means 1209 * that this CPU will have no coordination with other CPUs. 1210 */ 1211 if (acpi_processor_get_tsd(pr)) { 1212 pthrottling = &pr->throttling; 1213 pthrottling->tsd_valid_flag = 0; 1214 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); 1215 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 1216 } 1217 1218 /* 1219 * PIIX4 Errata: We don't support throttling on the original PIIX4. 1220 * This shouldn't be an issue as few (if any) mobile systems ever 1221 * used this part. 1222 */ 1223 if (errata.piix4.throttle) { 1224 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1225 "Throttling not supported on PIIX4 A- or B-step\n")); 1226 return 0; 1227 } 1228 1229 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n", 1230 pr->throttling.state_count)); 1231 1232 pr->flags.throttling = 1; 1233 1234 /* 1235 * Disable throttling (if enabled). We'll let subsequent policy (e.g. 1236 * thermal) decide to lower performance if it so chooses, but for now 1237 * we'll crank up the speed. 1238 */ 1239 1240 result = acpi_processor_get_throttling(pr); 1241 if (result) 1242 goto end; 1243 1244 if (pr->throttling.state) { 1245 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1246 "Disabling throttling (was T%d)\n", 1247 pr->throttling.state)); 1248 result = acpi_processor_set_throttling(pr, 0, false); 1249 if (result) 1250 goto end; 1251 } 1252 1253 end: 1254 if (result) 1255 pr->flags.throttling = 0; 1256 1257 return result; 1258 } 1259 1260