1 /* 2 * processor_throttling.c - Throttling submodule of the ACPI processor driver 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> 7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 8 * - Added processor hotplug support 9 * 10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2 of the License, or (at 15 * your option) any later version. 16 * 17 * This program is distributed in the hope that it will be useful, but 18 * WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 * General Public License for more details. 21 * 22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 23 */ 24 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/slab.h> 28 #include <linux/init.h> 29 #include <linux/sched.h> 30 #include <linux/cpufreq.h> 31 #include <linux/acpi.h> 32 #include <acpi/processor.h> 33 #include <asm/io.h> 34 #include <linux/uaccess.h> 35 36 #define PREFIX "ACPI: " 37 38 #define ACPI_PROCESSOR_CLASS "processor" 39 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 40 ACPI_MODULE_NAME("processor_throttling"); 41 42 /* ignore_tpc: 43 * 0 -> acpi processor driver doesn't ignore _TPC values 44 * 1 -> acpi processor driver ignores _TPC values 45 */ 46 static int ignore_tpc; 47 module_param(ignore_tpc, int, 0644); 48 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support"); 49 50 struct throttling_tstate { 51 unsigned int cpu; /* cpu nr */ 52 int target_state; /* target T-state */ 53 }; 54 55 struct acpi_processor_throttling_arg { 56 struct acpi_processor *pr; 57 int target_state; 58 bool force; 59 }; 60 61 #define THROTTLING_PRECHANGE (1) 62 #define THROTTLING_POSTCHANGE (2) 63 64 static int acpi_processor_get_throttling(struct acpi_processor *pr); 65 static int __acpi_processor_set_throttling(struct acpi_processor *pr, 66 int state, bool force, bool direct); 67 68 static int acpi_processor_update_tsd_coord(void) 69 { 70 int count, count_target; 71 int retval = 0; 72 unsigned int i, j; 73 cpumask_var_t covered_cpus; 74 struct acpi_processor *pr, *match_pr; 75 struct acpi_tsd_package *pdomain, *match_pdomain; 76 struct acpi_processor_throttling *pthrottling, *match_pthrottling; 77 78 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) 79 return -ENOMEM; 80 81 /* 82 * Now that we have _TSD data from all CPUs, lets setup T-state 83 * coordination between all CPUs. 84 */ 85 for_each_possible_cpu(i) { 86 pr = per_cpu(processors, i); 87 if (!pr) 88 continue; 89 90 /* Basic validity check for domain info */ 91 pthrottling = &(pr->throttling); 92 93 /* 94 * If tsd package for one cpu is invalid, the coordination 95 * among all CPUs is thought as invalid. 96 * Maybe it is ugly. 97 */ 98 if (!pthrottling->tsd_valid_flag) { 99 retval = -EINVAL; 100 break; 101 } 102 } 103 if (retval) 104 goto err_ret; 105 106 for_each_possible_cpu(i) { 107 pr = per_cpu(processors, i); 108 if (!pr) 109 continue; 110 111 if (cpumask_test_cpu(i, covered_cpus)) 112 continue; 113 pthrottling = &pr->throttling; 114 115 pdomain = &(pthrottling->domain_info); 116 cpumask_set_cpu(i, pthrottling->shared_cpu_map); 117 cpumask_set_cpu(i, covered_cpus); 118 /* 119 * If the number of processor in the TSD domain is 1, it is 120 * unnecessary to parse the coordination for this CPU. 121 */ 122 if (pdomain->num_processors <= 1) 123 continue; 124 125 /* Validate the Domain info */ 126 count_target = pdomain->num_processors; 127 count = 1; 128 129 for_each_possible_cpu(j) { 130 if (i == j) 131 continue; 132 133 match_pr = per_cpu(processors, j); 134 if (!match_pr) 135 continue; 136 137 match_pthrottling = &(match_pr->throttling); 138 match_pdomain = &(match_pthrottling->domain_info); 139 if (match_pdomain->domain != pdomain->domain) 140 continue; 141 142 /* Here i and j are in the same domain. 143 * If two TSD packages have the same domain, they 144 * should have the same num_porcessors and 145 * coordination type. Otherwise it will be regarded 146 * as illegal. 147 */ 148 if (match_pdomain->num_processors != count_target) { 149 retval = -EINVAL; 150 goto err_ret; 151 } 152 153 if (pdomain->coord_type != match_pdomain->coord_type) { 154 retval = -EINVAL; 155 goto err_ret; 156 } 157 158 cpumask_set_cpu(j, covered_cpus); 159 cpumask_set_cpu(j, pthrottling->shared_cpu_map); 160 count++; 161 } 162 for_each_possible_cpu(j) { 163 if (i == j) 164 continue; 165 166 match_pr = per_cpu(processors, j); 167 if (!match_pr) 168 continue; 169 170 match_pthrottling = &(match_pr->throttling); 171 match_pdomain = &(match_pthrottling->domain_info); 172 if (match_pdomain->domain != pdomain->domain) 173 continue; 174 175 /* 176 * If some CPUS have the same domain, they 177 * will have the same shared_cpu_map. 178 */ 179 cpumask_copy(match_pthrottling->shared_cpu_map, 180 pthrottling->shared_cpu_map); 181 } 182 } 183 184 err_ret: 185 free_cpumask_var(covered_cpus); 186 187 for_each_possible_cpu(i) { 188 pr = per_cpu(processors, i); 189 if (!pr) 190 continue; 191 192 /* 193 * Assume no coordination on any error parsing domain info. 194 * The coordination type will be forced as SW_ALL. 195 */ 196 if (retval) { 197 pthrottling = &(pr->throttling); 198 cpumask_clear(pthrottling->shared_cpu_map); 199 cpumask_set_cpu(i, pthrottling->shared_cpu_map); 200 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 201 } 202 } 203 204 return retval; 205 } 206 207 /* 208 * Update the T-state coordination after the _TSD 209 * data for all cpus is obtained. 210 */ 211 void acpi_processor_throttling_init(void) 212 { 213 if (acpi_processor_update_tsd_coord()) { 214 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 215 "Assume no T-state coordination\n")); 216 } 217 218 return; 219 } 220 221 static int acpi_processor_throttling_notifier(unsigned long event, void *data) 222 { 223 struct throttling_tstate *p_tstate = data; 224 struct acpi_processor *pr; 225 unsigned int cpu ; 226 int target_state; 227 struct acpi_processor_limit *p_limit; 228 struct acpi_processor_throttling *p_throttling; 229 230 cpu = p_tstate->cpu; 231 pr = per_cpu(processors, cpu); 232 if (!pr) { 233 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n")); 234 return 0; 235 } 236 if (!pr->flags.throttling) { 237 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is " 238 "unsupported on CPU %d\n", cpu)); 239 return 0; 240 } 241 target_state = p_tstate->target_state; 242 p_throttling = &(pr->throttling); 243 switch (event) { 244 case THROTTLING_PRECHANGE: 245 /* 246 * Prechange event is used to choose one proper t-state, 247 * which meets the limits of thermal, user and _TPC. 248 */ 249 p_limit = &pr->limit; 250 if (p_limit->thermal.tx > target_state) 251 target_state = p_limit->thermal.tx; 252 if (p_limit->user.tx > target_state) 253 target_state = p_limit->user.tx; 254 if (pr->throttling_platform_limit > target_state) 255 target_state = pr->throttling_platform_limit; 256 if (target_state >= p_throttling->state_count) { 257 printk(KERN_WARNING 258 "Exceed the limit of T-state \n"); 259 target_state = p_throttling->state_count - 1; 260 } 261 p_tstate->target_state = target_state; 262 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:" 263 "target T-state of CPU %d is T%d\n", 264 cpu, target_state)); 265 break; 266 case THROTTLING_POSTCHANGE: 267 /* 268 * Postchange event is only used to update the 269 * T-state flag of acpi_processor_throttling. 270 */ 271 p_throttling->state = target_state; 272 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:" 273 "CPU %d is switched to T%d\n", 274 cpu, target_state)); 275 break; 276 default: 277 printk(KERN_WARNING 278 "Unsupported Throttling notifier event\n"); 279 break; 280 } 281 282 return 0; 283 } 284 285 /* 286 * _TPC - Throttling Present Capabilities 287 */ 288 static int acpi_processor_get_platform_limit(struct acpi_processor *pr) 289 { 290 acpi_status status = 0; 291 unsigned long long tpc = 0; 292 293 if (!pr) 294 return -EINVAL; 295 296 if (ignore_tpc) 297 goto end; 298 299 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc); 300 if (ACPI_FAILURE(status)) { 301 if (status != AE_NOT_FOUND) { 302 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC")); 303 } 304 return -ENODEV; 305 } 306 307 end: 308 pr->throttling_platform_limit = (int)tpc; 309 return 0; 310 } 311 312 int acpi_processor_tstate_has_changed(struct acpi_processor *pr) 313 { 314 int result = 0; 315 int throttling_limit; 316 int current_state; 317 struct acpi_processor_limit *limit; 318 int target_state; 319 320 if (ignore_tpc) 321 return 0; 322 323 result = acpi_processor_get_platform_limit(pr); 324 if (result) { 325 /* Throttling Limit is unsupported */ 326 return result; 327 } 328 329 throttling_limit = pr->throttling_platform_limit; 330 if (throttling_limit >= pr->throttling.state_count) { 331 /* Uncorrect Throttling Limit */ 332 return -EINVAL; 333 } 334 335 current_state = pr->throttling.state; 336 if (current_state > throttling_limit) { 337 /* 338 * The current state can meet the requirement of 339 * _TPC limit. But it is reasonable that OSPM changes 340 * t-states from high to low for better performance. 341 * Of course the limit condition of thermal 342 * and user should be considered. 343 */ 344 limit = &pr->limit; 345 target_state = throttling_limit; 346 if (limit->thermal.tx > target_state) 347 target_state = limit->thermal.tx; 348 if (limit->user.tx > target_state) 349 target_state = limit->user.tx; 350 } else if (current_state == throttling_limit) { 351 /* 352 * Unnecessary to change the throttling state 353 */ 354 return 0; 355 } else { 356 /* 357 * If the current state is lower than the limit of _TPC, it 358 * will be forced to switch to the throttling state defined 359 * by throttling_platfor_limit. 360 * Because the previous state meets with the limit condition 361 * of thermal and user, it is unnecessary to check it again. 362 */ 363 target_state = throttling_limit; 364 } 365 return acpi_processor_set_throttling(pr, target_state, false); 366 } 367 368 /* 369 * This function is used to reevaluate whether the T-state is valid 370 * after one CPU is onlined/offlined. 371 * It is noted that it won't reevaluate the following properties for 372 * the T-state. 373 * 1. Control method. 374 * 2. the number of supported T-state 375 * 3. TSD domain 376 */ 377 void acpi_processor_reevaluate_tstate(struct acpi_processor *pr, 378 bool is_dead) 379 { 380 int result = 0; 381 382 if (is_dead) { 383 /* When one CPU is offline, the T-state throttling 384 * will be invalidated. 385 */ 386 pr->flags.throttling = 0; 387 return; 388 } 389 /* the following is to recheck whether the T-state is valid for 390 * the online CPU 391 */ 392 if (!pr->throttling.state_count) { 393 /* If the number of T-state is invalid, it is 394 * invalidated. 395 */ 396 pr->flags.throttling = 0; 397 return; 398 } 399 pr->flags.throttling = 1; 400 401 /* Disable throttling (if enabled). We'll let subsequent 402 * policy (e.g.thermal) decide to lower performance if it 403 * so chooses, but for now we'll crank up the speed. 404 */ 405 406 result = acpi_processor_get_throttling(pr); 407 if (result) 408 goto end; 409 410 if (pr->throttling.state) { 411 result = acpi_processor_set_throttling(pr, 0, false); 412 if (result) 413 goto end; 414 } 415 416 end: 417 if (result) 418 pr->flags.throttling = 0; 419 } 420 /* 421 * _PTC - Processor Throttling Control (and status) register location 422 */ 423 static int acpi_processor_get_throttling_control(struct acpi_processor *pr) 424 { 425 int result = 0; 426 acpi_status status = 0; 427 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 428 union acpi_object *ptc = NULL; 429 union acpi_object obj = { 0 }; 430 struct acpi_processor_throttling *throttling; 431 432 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer); 433 if (ACPI_FAILURE(status)) { 434 if (status != AE_NOT_FOUND) { 435 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC")); 436 } 437 return -ENODEV; 438 } 439 440 ptc = (union acpi_object *)buffer.pointer; 441 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE) 442 || (ptc->package.count != 2)) { 443 printk(KERN_ERR PREFIX "Invalid _PTC data\n"); 444 result = -EFAULT; 445 goto end; 446 } 447 448 /* 449 * control_register 450 */ 451 452 obj = ptc->package.elements[0]; 453 454 if ((obj.type != ACPI_TYPE_BUFFER) 455 || (obj.buffer.length < sizeof(struct acpi_ptc_register)) 456 || (obj.buffer.pointer == NULL)) { 457 printk(KERN_ERR PREFIX 458 "Invalid _PTC data (control_register)\n"); 459 result = -EFAULT; 460 goto end; 461 } 462 memcpy(&pr->throttling.control_register, obj.buffer.pointer, 463 sizeof(struct acpi_ptc_register)); 464 465 /* 466 * status_register 467 */ 468 469 obj = ptc->package.elements[1]; 470 471 if ((obj.type != ACPI_TYPE_BUFFER) 472 || (obj.buffer.length < sizeof(struct acpi_ptc_register)) 473 || (obj.buffer.pointer == NULL)) { 474 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n"); 475 result = -EFAULT; 476 goto end; 477 } 478 479 memcpy(&pr->throttling.status_register, obj.buffer.pointer, 480 sizeof(struct acpi_ptc_register)); 481 482 throttling = &pr->throttling; 483 484 if ((throttling->control_register.bit_width + 485 throttling->control_register.bit_offset) > 32) { 486 printk(KERN_ERR PREFIX "Invalid _PTC control register\n"); 487 result = -EFAULT; 488 goto end; 489 } 490 491 if ((throttling->status_register.bit_width + 492 throttling->status_register.bit_offset) > 32) { 493 printk(KERN_ERR PREFIX "Invalid _PTC status register\n"); 494 result = -EFAULT; 495 goto end; 496 } 497 498 end: 499 kfree(buffer.pointer); 500 501 return result; 502 } 503 504 /* 505 * _TSS - Throttling Supported States 506 */ 507 static int acpi_processor_get_throttling_states(struct acpi_processor *pr) 508 { 509 int result = 0; 510 acpi_status status = AE_OK; 511 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 512 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" }; 513 struct acpi_buffer state = { 0, NULL }; 514 union acpi_object *tss = NULL; 515 int i; 516 517 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer); 518 if (ACPI_FAILURE(status)) { 519 if (status != AE_NOT_FOUND) { 520 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS")); 521 } 522 return -ENODEV; 523 } 524 525 tss = buffer.pointer; 526 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) { 527 printk(KERN_ERR PREFIX "Invalid _TSS data\n"); 528 result = -EFAULT; 529 goto end; 530 } 531 532 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n", 533 tss->package.count)); 534 535 pr->throttling.state_count = tss->package.count; 536 pr->throttling.states_tss = 537 kmalloc_array(tss->package.count, 538 sizeof(struct acpi_processor_tx_tss), 539 GFP_KERNEL); 540 if (!pr->throttling.states_tss) { 541 result = -ENOMEM; 542 goto end; 543 } 544 545 for (i = 0; i < pr->throttling.state_count; i++) { 546 547 struct acpi_processor_tx_tss *tx = 548 (struct acpi_processor_tx_tss *)&(pr->throttling. 549 states_tss[i]); 550 551 state.length = sizeof(struct acpi_processor_tx_tss); 552 state.pointer = tx; 553 554 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i)); 555 556 status = acpi_extract_package(&(tss->package.elements[i]), 557 &format, &state); 558 if (ACPI_FAILURE(status)) { 559 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data")); 560 result = -EFAULT; 561 kfree(pr->throttling.states_tss); 562 goto end; 563 } 564 565 if (!tx->freqpercentage) { 566 printk(KERN_ERR PREFIX 567 "Invalid _TSS data: freq is zero\n"); 568 result = -EFAULT; 569 kfree(pr->throttling.states_tss); 570 goto end; 571 } 572 } 573 574 end: 575 kfree(buffer.pointer); 576 577 return result; 578 } 579 580 /* 581 * _TSD - T-State Dependencies 582 */ 583 static int acpi_processor_get_tsd(struct acpi_processor *pr) 584 { 585 int result = 0; 586 acpi_status status = AE_OK; 587 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 588 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" }; 589 struct acpi_buffer state = { 0, NULL }; 590 union acpi_object *tsd = NULL; 591 struct acpi_tsd_package *pdomain; 592 struct acpi_processor_throttling *pthrottling; 593 594 pthrottling = &pr->throttling; 595 pthrottling->tsd_valid_flag = 0; 596 597 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer); 598 if (ACPI_FAILURE(status)) { 599 if (status != AE_NOT_FOUND) { 600 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD")); 601 } 602 return -ENODEV; 603 } 604 605 tsd = buffer.pointer; 606 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) { 607 printk(KERN_ERR PREFIX "Invalid _TSD data\n"); 608 result = -EFAULT; 609 goto end; 610 } 611 612 if (tsd->package.count != 1) { 613 printk(KERN_ERR PREFIX "Invalid _TSD data\n"); 614 result = -EFAULT; 615 goto end; 616 } 617 618 pdomain = &(pr->throttling.domain_info); 619 620 state.length = sizeof(struct acpi_tsd_package); 621 state.pointer = pdomain; 622 623 status = acpi_extract_package(&(tsd->package.elements[0]), 624 &format, &state); 625 if (ACPI_FAILURE(status)) { 626 printk(KERN_ERR PREFIX "Invalid _TSD data\n"); 627 result = -EFAULT; 628 goto end; 629 } 630 631 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) { 632 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n"); 633 result = -EFAULT; 634 goto end; 635 } 636 637 if (pdomain->revision != ACPI_TSD_REV0_REVISION) { 638 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n"); 639 result = -EFAULT; 640 goto end; 641 } 642 643 pthrottling = &pr->throttling; 644 pthrottling->tsd_valid_flag = 1; 645 pthrottling->shared_type = pdomain->coord_type; 646 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); 647 /* 648 * If the coordination type is not defined in ACPI spec, 649 * the tsd_valid_flag will be clear and coordination type 650 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL. 651 */ 652 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && 653 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && 654 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { 655 pthrottling->tsd_valid_flag = 0; 656 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 657 } 658 659 end: 660 kfree(buffer.pointer); 661 return result; 662 } 663 664 /* -------------------------------------------------------------------------- 665 Throttling Control 666 -------------------------------------------------------------------------- */ 667 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr) 668 { 669 int state = 0; 670 u32 value = 0; 671 u32 duty_mask = 0; 672 u32 duty_value = 0; 673 674 if (!pr) 675 return -EINVAL; 676 677 if (!pr->flags.throttling) 678 return -ENODEV; 679 680 /* 681 * We don't care about error returns - we just try to mark 682 * these reserved so that nobody else is confused into thinking 683 * that this region might be unused.. 684 * 685 * (In particular, allocating the IO range for Cardbus) 686 */ 687 request_region(pr->throttling.address, 6, "ACPI CPU throttle"); 688 689 pr->throttling.state = 0; 690 691 duty_mask = pr->throttling.state_count - 1; 692 693 duty_mask <<= pr->throttling.duty_offset; 694 695 local_irq_disable(); 696 697 value = inl(pr->throttling.address); 698 699 /* 700 * Compute the current throttling state when throttling is enabled 701 * (bit 4 is on). 702 */ 703 if (value & 0x10) { 704 duty_value = value & duty_mask; 705 duty_value >>= pr->throttling.duty_offset; 706 707 if (duty_value) 708 state = pr->throttling.state_count - duty_value; 709 } 710 711 pr->throttling.state = state; 712 713 local_irq_enable(); 714 715 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 716 "Throttling state is T%d (%d%% throttling applied)\n", 717 state, pr->throttling.states[state].performance)); 718 719 return 0; 720 } 721 722 #ifdef CONFIG_X86 723 static int acpi_throttling_rdmsr(u64 *value) 724 { 725 u64 msr_high, msr_low; 726 u64 msr = 0; 727 int ret = -1; 728 729 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || 730 !this_cpu_has(X86_FEATURE_ACPI)) { 731 printk(KERN_ERR PREFIX 732 "HARDWARE addr space,NOT supported yet\n"); 733 } else { 734 msr_low = 0; 735 msr_high = 0; 736 rdmsr_safe(MSR_IA32_THERM_CONTROL, 737 (u32 *)&msr_low , (u32 *) &msr_high); 738 msr = (msr_high << 32) | msr_low; 739 *value = (u64) msr; 740 ret = 0; 741 } 742 return ret; 743 } 744 745 static int acpi_throttling_wrmsr(u64 value) 746 { 747 int ret = -1; 748 u64 msr; 749 750 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) || 751 !this_cpu_has(X86_FEATURE_ACPI)) { 752 printk(KERN_ERR PREFIX 753 "HARDWARE addr space,NOT supported yet\n"); 754 } else { 755 msr = value; 756 wrmsr_safe(MSR_IA32_THERM_CONTROL, 757 msr & 0xffffffff, msr >> 32); 758 ret = 0; 759 } 760 return ret; 761 } 762 #else 763 static int acpi_throttling_rdmsr(u64 *value) 764 { 765 printk(KERN_ERR PREFIX 766 "HARDWARE addr space,NOT supported yet\n"); 767 return -1; 768 } 769 770 static int acpi_throttling_wrmsr(u64 value) 771 { 772 printk(KERN_ERR PREFIX 773 "HARDWARE addr space,NOT supported yet\n"); 774 return -1; 775 } 776 #endif 777 778 static int acpi_read_throttling_status(struct acpi_processor *pr, 779 u64 *value) 780 { 781 u32 bit_width, bit_offset; 782 u32 ptc_value; 783 u64 ptc_mask; 784 struct acpi_processor_throttling *throttling; 785 int ret = -1; 786 787 throttling = &pr->throttling; 788 switch (throttling->status_register.space_id) { 789 case ACPI_ADR_SPACE_SYSTEM_IO: 790 bit_width = throttling->status_register.bit_width; 791 bit_offset = throttling->status_register.bit_offset; 792 793 acpi_os_read_port((acpi_io_address) throttling->status_register. 794 address, &ptc_value, 795 (u32) (bit_width + bit_offset)); 796 ptc_mask = (1 << bit_width) - 1; 797 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask); 798 ret = 0; 799 break; 800 case ACPI_ADR_SPACE_FIXED_HARDWARE: 801 ret = acpi_throttling_rdmsr(value); 802 break; 803 default: 804 printk(KERN_ERR PREFIX "Unknown addr space %d\n", 805 (u32) (throttling->status_register.space_id)); 806 } 807 return ret; 808 } 809 810 static int acpi_write_throttling_state(struct acpi_processor *pr, 811 u64 value) 812 { 813 u32 bit_width, bit_offset; 814 u64 ptc_value; 815 u64 ptc_mask; 816 struct acpi_processor_throttling *throttling; 817 int ret = -1; 818 819 throttling = &pr->throttling; 820 switch (throttling->control_register.space_id) { 821 case ACPI_ADR_SPACE_SYSTEM_IO: 822 bit_width = throttling->control_register.bit_width; 823 bit_offset = throttling->control_register.bit_offset; 824 ptc_mask = (1 << bit_width) - 1; 825 ptc_value = value & ptc_mask; 826 827 acpi_os_write_port((acpi_io_address) throttling-> 828 control_register.address, 829 (u32) (ptc_value << bit_offset), 830 (u32) (bit_width + bit_offset)); 831 ret = 0; 832 break; 833 case ACPI_ADR_SPACE_FIXED_HARDWARE: 834 ret = acpi_throttling_wrmsr(value); 835 break; 836 default: 837 printk(KERN_ERR PREFIX "Unknown addr space %d\n", 838 (u32) (throttling->control_register.space_id)); 839 } 840 return ret; 841 } 842 843 static int acpi_get_throttling_state(struct acpi_processor *pr, 844 u64 value) 845 { 846 int i; 847 848 for (i = 0; i < pr->throttling.state_count; i++) { 849 struct acpi_processor_tx_tss *tx = 850 (struct acpi_processor_tx_tss *)&(pr->throttling. 851 states_tss[i]); 852 if (tx->control == value) 853 return i; 854 } 855 return -1; 856 } 857 858 static int acpi_get_throttling_value(struct acpi_processor *pr, 859 int state, u64 *value) 860 { 861 int ret = -1; 862 863 if (state >= 0 && state <= pr->throttling.state_count) { 864 struct acpi_processor_tx_tss *tx = 865 (struct acpi_processor_tx_tss *)&(pr->throttling. 866 states_tss[state]); 867 *value = tx->control; 868 ret = 0; 869 } 870 return ret; 871 } 872 873 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr) 874 { 875 int state = 0; 876 int ret; 877 u64 value; 878 879 if (!pr) 880 return -EINVAL; 881 882 if (!pr->flags.throttling) 883 return -ENODEV; 884 885 pr->throttling.state = 0; 886 887 value = 0; 888 ret = acpi_read_throttling_status(pr, &value); 889 if (ret >= 0) { 890 state = acpi_get_throttling_state(pr, value); 891 if (state == -1) { 892 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 893 "Invalid throttling state, reset\n")); 894 state = 0; 895 ret = __acpi_processor_set_throttling(pr, state, true, 896 true); 897 if (ret) 898 return ret; 899 } 900 pr->throttling.state = state; 901 } 902 903 return 0; 904 } 905 906 static long __acpi_processor_get_throttling(void *data) 907 { 908 struct acpi_processor *pr = data; 909 910 return pr->throttling.acpi_processor_get_throttling(pr); 911 } 912 913 static int call_on_cpu(int cpu, long (*fn)(void *), void *arg, bool direct) 914 { 915 if (direct || (is_percpu_thread() && cpu == smp_processor_id())) 916 return fn(arg); 917 return work_on_cpu(cpu, fn, arg); 918 } 919 920 static int acpi_processor_get_throttling(struct acpi_processor *pr) 921 { 922 if (!pr) 923 return -EINVAL; 924 925 if (!pr->flags.throttling) 926 return -ENODEV; 927 928 /* 929 * This is either called from the CPU hotplug callback of 930 * processor_driver or via the ACPI probe function. In the latter 931 * case the CPU is not guaranteed to be online. Both call sites are 932 * protected against CPU hotplug. 933 */ 934 if (!cpu_online(pr->id)) 935 return -ENODEV; 936 937 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false); 938 } 939 940 static int acpi_processor_get_fadt_info(struct acpi_processor *pr) 941 { 942 int i, step; 943 944 if (!pr->throttling.address) { 945 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n")); 946 return -EINVAL; 947 } else if (!pr->throttling.duty_width) { 948 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n")); 949 return -EINVAL; 950 } 951 /* TBD: Support duty_cycle values that span bit 4. */ 952 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) { 953 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n"); 954 return -EINVAL; 955 } 956 957 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width; 958 959 /* 960 * Compute state values. Note that throttling displays a linear power 961 * performance relationship (at 50% performance the CPU will consume 962 * 50% power). Values are in 1/10th of a percent to preserve accuracy. 963 */ 964 965 step = (1000 / pr->throttling.state_count); 966 967 for (i = 0; i < pr->throttling.state_count; i++) { 968 pr->throttling.states[i].performance = 1000 - step * i; 969 pr->throttling.states[i].power = 1000 - step * i; 970 } 971 return 0; 972 } 973 974 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr, 975 int state, bool force) 976 { 977 u32 value = 0; 978 u32 duty_mask = 0; 979 u32 duty_value = 0; 980 981 if (!pr) 982 return -EINVAL; 983 984 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 985 return -EINVAL; 986 987 if (!pr->flags.throttling) 988 return -ENODEV; 989 990 if (!force && (state == pr->throttling.state)) 991 return 0; 992 993 if (state < pr->throttling_platform_limit) 994 return -EPERM; 995 /* 996 * Calculate the duty_value and duty_mask. 997 */ 998 if (state) { 999 duty_value = pr->throttling.state_count - state; 1000 1001 duty_value <<= pr->throttling.duty_offset; 1002 1003 /* Used to clear all duty_value bits */ 1004 duty_mask = pr->throttling.state_count - 1; 1005 1006 duty_mask <<= acpi_gbl_FADT.duty_offset; 1007 duty_mask = ~duty_mask; 1008 } 1009 1010 local_irq_disable(); 1011 1012 /* 1013 * Disable throttling by writing a 0 to bit 4. Note that we must 1014 * turn it off before you can change the duty_value. 1015 */ 1016 value = inl(pr->throttling.address); 1017 if (value & 0x10) { 1018 value &= 0xFFFFFFEF; 1019 outl(value, pr->throttling.address); 1020 } 1021 1022 /* 1023 * Write the new duty_value and then enable throttling. Note 1024 * that a state value of 0 leaves throttling disabled. 1025 */ 1026 if (state) { 1027 value &= duty_mask; 1028 value |= duty_value; 1029 outl(value, pr->throttling.address); 1030 1031 value |= 0x00000010; 1032 outl(value, pr->throttling.address); 1033 } 1034 1035 pr->throttling.state = state; 1036 1037 local_irq_enable(); 1038 1039 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1040 "Throttling state set to T%d (%d%%)\n", state, 1041 (pr->throttling.states[state].performance ? pr-> 1042 throttling.states[state].performance / 10 : 0))); 1043 1044 return 0; 1045 } 1046 1047 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr, 1048 int state, bool force) 1049 { 1050 int ret; 1051 u64 value; 1052 1053 if (!pr) 1054 return -EINVAL; 1055 1056 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 1057 return -EINVAL; 1058 1059 if (!pr->flags.throttling) 1060 return -ENODEV; 1061 1062 if (!force && (state == pr->throttling.state)) 1063 return 0; 1064 1065 if (state < pr->throttling_platform_limit) 1066 return -EPERM; 1067 1068 value = 0; 1069 ret = acpi_get_throttling_value(pr, state, &value); 1070 if (ret >= 0) { 1071 acpi_write_throttling_state(pr, value); 1072 pr->throttling.state = state; 1073 } 1074 1075 return 0; 1076 } 1077 1078 static long acpi_processor_throttling_fn(void *data) 1079 { 1080 struct acpi_processor_throttling_arg *arg = data; 1081 struct acpi_processor *pr = arg->pr; 1082 1083 return pr->throttling.acpi_processor_set_throttling(pr, 1084 arg->target_state, arg->force); 1085 } 1086 1087 static int __acpi_processor_set_throttling(struct acpi_processor *pr, 1088 int state, bool force, bool direct) 1089 { 1090 int ret = 0; 1091 unsigned int i; 1092 struct acpi_processor *match_pr; 1093 struct acpi_processor_throttling *p_throttling; 1094 struct acpi_processor_throttling_arg arg; 1095 struct throttling_tstate t_state; 1096 1097 if (!pr) 1098 return -EINVAL; 1099 1100 if (!pr->flags.throttling) 1101 return -ENODEV; 1102 1103 if ((state < 0) || (state > (pr->throttling.state_count - 1))) 1104 return -EINVAL; 1105 1106 if (cpu_is_offline(pr->id)) { 1107 /* 1108 * the cpu pointed by pr->id is offline. Unnecessary to change 1109 * the throttling state any more. 1110 */ 1111 return -ENODEV; 1112 } 1113 1114 t_state.target_state = state; 1115 p_throttling = &(pr->throttling); 1116 1117 /* 1118 * The throttling notifier will be called for every 1119 * affected cpu in order to get one proper T-state. 1120 * The notifier event is THROTTLING_PRECHANGE. 1121 */ 1122 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { 1123 t_state.cpu = i; 1124 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE, 1125 &t_state); 1126 } 1127 /* 1128 * The function of acpi_processor_set_throttling will be called 1129 * to switch T-state. If the coordination type is SW_ALL or HW_ALL, 1130 * it is necessary to call it for every affected cpu. Otherwise 1131 * it can be called only for the cpu pointed by pr. 1132 */ 1133 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) { 1134 arg.pr = pr; 1135 arg.target_state = state; 1136 arg.force = force; 1137 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg, 1138 direct); 1139 } else { 1140 /* 1141 * When the T-state coordination is SW_ALL or HW_ALL, 1142 * it is necessary to set T-state for every affected 1143 * cpus. 1144 */ 1145 for_each_cpu_and(i, cpu_online_mask, 1146 p_throttling->shared_cpu_map) { 1147 match_pr = per_cpu(processors, i); 1148 /* 1149 * If the pointer is invalid, we will report the 1150 * error message and continue. 1151 */ 1152 if (!match_pr) { 1153 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1154 "Invalid Pointer for CPU %d\n", i)); 1155 continue; 1156 } 1157 /* 1158 * If the throttling control is unsupported on CPU i, 1159 * we will report the error message and continue. 1160 */ 1161 if (!match_pr->flags.throttling) { 1162 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1163 "Throttling Control is unsupported " 1164 "on CPU %d\n", i)); 1165 continue; 1166 } 1167 1168 arg.pr = match_pr; 1169 arg.target_state = state; 1170 arg.force = force; 1171 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, 1172 &arg, direct); 1173 } 1174 } 1175 /* 1176 * After the set_throttling is called, the 1177 * throttling notifier is called for every 1178 * affected cpu to update the T-states. 1179 * The notifier event is THROTTLING_POSTCHANGE 1180 */ 1181 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) { 1182 t_state.cpu = i; 1183 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE, 1184 &t_state); 1185 } 1186 1187 return ret; 1188 } 1189 1190 int acpi_processor_set_throttling(struct acpi_processor *pr, int state, 1191 bool force) 1192 { 1193 return __acpi_processor_set_throttling(pr, state, force, false); 1194 } 1195 1196 int acpi_processor_get_throttling_info(struct acpi_processor *pr) 1197 { 1198 int result = 0; 1199 struct acpi_processor_throttling *pthrottling; 1200 1201 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1202 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n", 1203 pr->throttling.address, 1204 pr->throttling.duty_offset, 1205 pr->throttling.duty_width)); 1206 1207 /* 1208 * Evaluate _PTC, _TSS and _TPC 1209 * They must all be present or none of them can be used. 1210 */ 1211 if (acpi_processor_get_throttling_control(pr) || 1212 acpi_processor_get_throttling_states(pr) || 1213 acpi_processor_get_platform_limit(pr)) 1214 { 1215 pr->throttling.acpi_processor_get_throttling = 1216 &acpi_processor_get_throttling_fadt; 1217 pr->throttling.acpi_processor_set_throttling = 1218 &acpi_processor_set_throttling_fadt; 1219 if (acpi_processor_get_fadt_info(pr)) 1220 return 0; 1221 } else { 1222 pr->throttling.acpi_processor_get_throttling = 1223 &acpi_processor_get_throttling_ptc; 1224 pr->throttling.acpi_processor_set_throttling = 1225 &acpi_processor_set_throttling_ptc; 1226 } 1227 1228 /* 1229 * If TSD package for one CPU can't be parsed successfully, it means 1230 * that this CPU will have no coordination with other CPUs. 1231 */ 1232 if (acpi_processor_get_tsd(pr)) { 1233 pthrottling = &pr->throttling; 1234 pthrottling->tsd_valid_flag = 0; 1235 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map); 1236 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL; 1237 } 1238 1239 /* 1240 * PIIX4 Errata: We don't support throttling on the original PIIX4. 1241 * This shouldn't be an issue as few (if any) mobile systems ever 1242 * used this part. 1243 */ 1244 if (errata.piix4.throttle) { 1245 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1246 "Throttling not supported on PIIX4 A- or B-step\n")); 1247 return 0; 1248 } 1249 1250 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n", 1251 pr->throttling.state_count)); 1252 1253 pr->flags.throttling = 1; 1254 1255 /* 1256 * Disable throttling (if enabled). We'll let subsequent policy (e.g. 1257 * thermal) decide to lower performance if it so chooses, but for now 1258 * we'll crank up the speed. 1259 */ 1260 1261 result = acpi_processor_get_throttling(pr); 1262 if (result) 1263 goto end; 1264 1265 if (pr->throttling.state) { 1266 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 1267 "Disabling throttling (was T%d)\n", 1268 pr->throttling.state)); 1269 result = acpi_processor_set_throttling(pr, 0, false); 1270 if (result) 1271 goto end; 1272 } 1273 1274 end: 1275 if (result) 1276 pr->flags.throttling = 0; 1277 1278 return result; 1279 } 1280 1281