drivers/acpi/processor_throttling.c

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