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