drivers/acpi/processor_throttling.c

   1 /*
   2  * processor_throttling.c - Throttling submodule of the ACPI processor driver
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *  Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
   7  *  Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
   8  *                      - Added processor hotplug support
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/sched.h>
  33 #include <linux/cpufreq.h>
  34 #include <linux/proc_fs.h>
  35 #include <linux/seq_file.h>
  36
  37 #include <asm/io.h>
  38 #include <asm/uaccess.h>
  39
  40 #include <acpi/acpi_bus.h>
  41 #include <acpi/acpi_drivers.h>
  42 #include <acpi/processor.h>
  43
  44 #define ACPI_PROCESSOR_CLASS            "processor"
  45 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
  46 ACPI_MODULE_NAME("processor_throttling");
  47
  48 struct throttling_tstate {
  49         unsigned int cpu;               /* cpu nr */
  50         int target_state;               /* target T-state */
  51 };
  52
  53 #define THROTTLING_PRECHANGE       (1)
  54 #define THROTTLING_POSTCHANGE      (2)
  55
  56 static int acpi_processor_get_throttling(struct acpi_processor *pr);
  57 int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
  58
  59 static int acpi_processor_update_tsd_coord(void)
  60 {
  61         int count, count_target;
  62         int retval = 0;
  63         unsigned int i, j;
  64         cpumask_var_t covered_cpus;
  65         struct acpi_processor *pr, *match_pr;
  66         struct acpi_tsd_package *pdomain, *match_pdomain;
  67         struct acpi_processor_throttling *pthrottling, *match_pthrottling;
  68
  69         if (!alloc_cpumask_var(&covered_cpus, GFP_KERNEL))
  70                 return -ENOMEM;
  71
  72         /*
  73          * Now that we have _TSD data from all CPUs, lets setup T-state
  74          * coordination between all CPUs.
  75          */
  76         for_each_possible_cpu(i) {
  77                 pr = per_cpu(processors, i);
  78                 if (!pr)
  79                         continue;
  80
  81                 /* Basic validity check for domain info */
  82                 pthrottling = &(pr->throttling);
  83
  84                 /*
  85                  * If tsd package for one cpu is invalid, the coordination
  86                  * among all CPUs is thought as invalid.
  87                  * Maybe it is ugly.
  88                  */
  89                 if (!pthrottling->tsd_valid_flag) {
  90                         retval = -EINVAL;
  91                         break;
  92                 }
  93         }
  94         if (retval)
  95                 goto err_ret;
  96
  97         cpumask_clear(covered_cpus);
  98         for_each_possible_cpu(i) {
  99                 pr = per_cpu(processors, i);
 100                 if (!pr)
 101                         continue;
 102
 103                 if (cpumask_test_cpu(i, covered_cpus))
 104                         continue;
 105                 pthrottling = &pr->throttling;
 106
 107                 pdomain = &(pthrottling->domain_info);
 108                 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
 109                 cpumask_set_cpu(i, covered_cpus);
 110                 /*
 111                  * If the number of processor in the TSD domain is 1, it is
 112                  * unnecessary to parse the coordination for this CPU.
 113                  */
 114                 if (pdomain->num_processors <= 1)
 115                         continue;
 116
 117                 /* Validate the Domain info */
 118                 count_target = pdomain->num_processors;
 119                 count = 1;
 120
 121                 for_each_possible_cpu(j) {
 122                         if (i == j)
 123                                 continue;
 124
 125                         match_pr = per_cpu(processors, j);
 126                         if (!match_pr)
 127                                 continue;
 128
 129                         match_pthrottling = &(match_pr->throttling);
 130                         match_pdomain = &(match_pthrottling->domain_info);
 131                         if (match_pdomain->domain != pdomain->domain)
 132                                 continue;
 133
 134                         /* Here i and j are in the same domain.
 135                          * If two TSD packages have the same domain, they
 136                          * should have the same num_porcessors and
 137                          * coordination type. Otherwise it will be regarded
 138                          * as illegal.
 139                          */
 140                         if (match_pdomain->num_processors != count_target) {
 141                                 retval = -EINVAL;
 142                                 goto err_ret;
 143                         }
 144
 145                         if (pdomain->coord_type != match_pdomain->coord_type) {
 146                                 retval = -EINVAL;
 147                                 goto err_ret;
 148                         }
 149
 150                         cpumask_set_cpu(j, covered_cpus);
 151                         cpumask_set_cpu(j, pthrottling->shared_cpu_map);
 152                         count++;
 153                 }
 154                 for_each_possible_cpu(j) {
 155                         if (i == j)
 156                                 continue;
 157
 158                         match_pr = per_cpu(processors, j);
 159                         if (!match_pr)
 160                                 continue;
 161
 162                         match_pthrottling = &(match_pr->throttling);
 163                         match_pdomain = &(match_pthrottling->domain_info);
 164                         if (match_pdomain->domain != pdomain->domain)
 165                                 continue;
 166
 167                         /*
 168                          * If some CPUS have the same domain, they
 169                          * will have the same shared_cpu_map.
 170                          */
 171                         cpumask_copy(match_pthrottling->shared_cpu_map,
 172                                      pthrottling->shared_cpu_map);
 173                 }
 174         }
 175
 176 err_ret:
 177         free_cpumask_var(covered_cpus);
 178
 179         for_each_possible_cpu(i) {
 180                 pr = per_cpu(processors, i);
 181                 if (!pr)
 182                         continue;
 183
 184                 /*
 185                  * Assume no coordination on any error parsing domain info.
 186                  * The coordination type will be forced as SW_ALL.
 187                  */
 188                 if (retval) {
 189                         pthrottling = &(pr->throttling);
 190                         cpumask_clear(pthrottling->shared_cpu_map);
 191                         cpumask_set_cpu(i, pthrottling->shared_cpu_map);
 192                         pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
 193                 }
 194         }
 195
 196         return retval;
 197 }
 198
 199 /*
 200  * Update the T-state coordination after the _TSD
 201  * data for all cpus is obtained.
 202  */
 203 void acpi_processor_throttling_init(void)
 204 {
 205         if (acpi_processor_update_tsd_coord())
 206                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 207                         "Assume no T-state coordination\n"));
 208
 209         return;
 210 }
 211
 212 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
 213 {
 214         struct throttling_tstate *p_tstate = data;
 215         struct acpi_processor *pr;
 216         unsigned int cpu ;
 217         int target_state;
 218         struct acpi_processor_limit *p_limit;
 219         struct acpi_processor_throttling *p_throttling;
 220
 221         cpu = p_tstate->cpu;
 222         pr = per_cpu(processors, cpu);
 223         if (!pr) {
 224                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
 225                 return 0;
 226         }
 227         if (!pr->flags.throttling) {
 228                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
 229                                 "unsupported on CPU %d\n", cpu));
 230                 return 0;
 231         }
 232         target_state = p_tstate->target_state;
 233         p_throttling = &(pr->throttling);
 234         switch (event) {
 235         case THROTTLING_PRECHANGE:
 236                 /*
 237                  * Prechange event is used to choose one proper t-state,
 238                  * which meets the limits of thermal, user and _TPC.
 239                  */
 240                 p_limit = &pr->limit;
 241                 if (p_limit->thermal.tx > target_state)
 242                         target_state = p_limit->thermal.tx;
 243                 if (p_limit->user.tx > target_state)
 244                         target_state = p_limit->user.tx;
 245                 if (pr->throttling_platform_limit > target_state)
 246                         target_state = pr->throttling_platform_limit;
 247                 if (target_state >= p_throttling->state_count) {
 248                         printk(KERN_WARNING
 249                                 "Exceed the limit of T-state \n");
 250                         target_state = p_throttling->state_count - 1;
 251                 }
 252                 p_tstate->target_state = target_state;
 253                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
 254                                 "target T-state of CPU %d is T%d\n",
 255                                 cpu, target_state));
 256                 break;
 257         case THROTTLING_POSTCHANGE:
 258                 /*
 259                  * Postchange event is only used to update the
 260                  * T-state flag of acpi_processor_throttling.
 261                  */
 262                 p_throttling->state = target_state;
 263                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
 264                                 "CPU %d is switched to T%d\n",
 265                                 cpu, target_state));
 266                 break;
 267         default:
 268                 printk(KERN_WARNING
 269                         "Unsupported Throttling notifier event\n");
 270                 break;
 271         }
 272
 273         return 0;
 274 }
 275
 276 /*
 277  * _TPC - Throttling Present Capabilities
 278  */
 279 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
 280 {
 281         acpi_status status = 0;
 282         unsigned long long tpc = 0;
 283
 284         if (!pr)
 285                 return -EINVAL;
 286         status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
 287         if (ACPI_FAILURE(status)) {
 288                 if (status != AE_NOT_FOUND) {
 289                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
 290                 }
 291                 return -ENODEV;
 292         }
 293         pr->throttling_platform_limit = (int)tpc;
 294         return 0;
 295 }
 296
 297 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
 298 {
 299         int result = 0;
 300         int throttling_limit;
 301         int current_state;
 302         struct acpi_processor_limit *limit;
 303         int target_state;
 304
 305         result = acpi_processor_get_platform_limit(pr);
 306         if (result) {
 307                 /* Throttling Limit is unsupported */
 308                 return result;
 309         }
 310
 311         throttling_limit = pr->throttling_platform_limit;
 312         if (throttling_limit >= pr->throttling.state_count) {
 313                 /* Uncorrect Throttling Limit */
 314                 return -EINVAL;
 315         }
 316
 317         current_state = pr->throttling.state;
 318         if (current_state > throttling_limit) {
 319                 /*
 320                  * The current state can meet the requirement of
 321                  * _TPC limit. But it is reasonable that OSPM changes
 322                  * t-states from high to low for better performance.
 323                  * Of course the limit condition of thermal
 324                  * and user should be considered.
 325                  */
 326                 limit = &pr->limit;
 327                 target_state = throttling_limit;
 328                 if (limit->thermal.tx > target_state)
 329                         target_state = limit->thermal.tx;
 330                 if (limit->user.tx > target_state)
 331                         target_state = limit->user.tx;
 332         } else if (current_state == throttling_limit) {
 333                 /*
 334                  * Unnecessary to change the throttling state
 335                  */
 336                 return 0;
 337         } else {
 338                 /*
 339                  * If the current state is lower than the limit of _TPC, it
 340                  * will be forced to switch to the throttling state defined
 341                  * by throttling_platfor_limit.
 342                  * Because the previous state meets with the limit condition
 343                  * of thermal and user, it is unnecessary to check it again.
 344                  */
 345                 target_state = throttling_limit;
 346         }
 347         return acpi_processor_set_throttling(pr, target_state);
 348 }
 349
 350 /*
 351  * _PTC - Processor Throttling Control (and status) register location
 352  */
 353 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
 354 {
 355         int result = 0;
 356         acpi_status status = 0;
 357         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 358         union acpi_object *ptc = NULL;
 359         union acpi_object obj = { 0 };
 360         struct acpi_processor_throttling *throttling;
 361
 362         status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
 363         if (ACPI_FAILURE(status)) {
 364                 if (status != AE_NOT_FOUND) {
 365                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
 366                 }
 367                 return -ENODEV;
 368         }
 369
 370         ptc = (union acpi_object *)buffer.pointer;
 371         if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
 372             || (ptc->package.count != 2)) {
 373                 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
 374                 result = -EFAULT;
 375                 goto end;
 376         }
 377
 378         /*
 379          * control_register
 380          */
 381
 382         obj = ptc->package.elements[0];
 383
 384         if ((obj.type != ACPI_TYPE_BUFFER)
 385             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
 386             || (obj.buffer.pointer == NULL)) {
 387                 printk(KERN_ERR PREFIX
 388                        "Invalid _PTC data (control_register)\n");
 389                 result = -EFAULT;
 390                 goto end;
 391         }
 392         memcpy(&pr->throttling.control_register, obj.buffer.pointer,
 393                sizeof(struct acpi_ptc_register));
 394
 395         /*
 396          * status_register
 397          */
 398
 399         obj = ptc->package.elements[1];
 400
 401         if ((obj.type != ACPI_TYPE_BUFFER)
 402             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
 403             || (obj.buffer.pointer == NULL)) {
 404                 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
 405                 result = -EFAULT;
 406                 goto end;
 407         }
 408
 409         memcpy(&pr->throttling.status_register, obj.buffer.pointer,
 410                sizeof(struct acpi_ptc_register));
 411
 412         throttling = &pr->throttling;
 413
 414         if ((throttling->control_register.bit_width +
 415                 throttling->control_register.bit_offset) > 32) {
 416                 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
 417                 result = -EFAULT;
 418                 goto end;
 419         }
 420
 421         if ((throttling->status_register.bit_width +
 422                 throttling->status_register.bit_offset) > 32) {
 423                 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
 424                 result = -EFAULT;
 425                 goto end;
 426         }
 427
 428       end:
 429         kfree(buffer.pointer);
 430
 431         return result;
 432 }
 433
 434 /*
 435  * _TSS - Throttling Supported States
 436  */
 437 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
 438 {
 439         int result = 0;
 440         acpi_status status = AE_OK;
 441         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 442         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
 443         struct acpi_buffer state = { 0, NULL };
 444         union acpi_object *tss = NULL;
 445         int i;
 446
 447         status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
 448         if (ACPI_FAILURE(status)) {
 449                 if (status != AE_NOT_FOUND) {
 450                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
 451                 }
 452                 return -ENODEV;
 453         }
 454
 455         tss = buffer.pointer;
 456         if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
 457                 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
 458                 result = -EFAULT;
 459                 goto end;
 460         }
 461
 462         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
 463                           tss->package.count));
 464
 465         pr->throttling.state_count = tss->package.count;
 466         pr->throttling.states_tss =
 467             kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
 468                     GFP_KERNEL);
 469         if (!pr->throttling.states_tss) {
 470                 result = -ENOMEM;
 471                 goto end;
 472         }
 473
 474         for (i = 0; i < pr->throttling.state_count; i++) {
 475
 476                 struct acpi_processor_tx_tss *tx =
 477                     (struct acpi_processor_tx_tss *)&(pr->throttling.
 478                                                       states_tss[i]);
 479
 480                 state.length = sizeof(struct acpi_processor_tx_tss);
 481                 state.pointer = tx;
 482
 483                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
 484
 485                 status = acpi_extract_package(&(tss->package.elements[i]),
 486                                               &format, &state);
 487                 if (ACPI_FAILURE(status)) {
 488                         ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
 489                         result = -EFAULT;
 490                         kfree(pr->throttling.states_tss);
 491                         goto end;
 492                 }
 493
 494                 if (!tx->freqpercentage) {
 495                         printk(KERN_ERR PREFIX
 496                                "Invalid _TSS data: freq is zero\n");
 497                         result = -EFAULT;
 498                         kfree(pr->throttling.states_tss);
 499                         goto end;
 500                 }
 501         }
 502
 503       end:
 504         kfree(buffer.pointer);
 505
 506         return result;
 507 }
 508
 509 /*
 510  * _TSD - T-State Dependencies
 511  */
 512 static int acpi_processor_get_tsd(struct acpi_processor *pr)
 513 {
 514         int result = 0;
 515         acpi_status status = AE_OK;
 516         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 517         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
 518         struct acpi_buffer state = { 0, NULL };
 519         union acpi_object *tsd = NULL;
 520         struct acpi_tsd_package *pdomain;
 521         struct acpi_processor_throttling *pthrottling;
 522
 523         pthrottling = &pr->throttling;
 524         pthrottling->tsd_valid_flag = 0;
 525
 526         status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
 527         if (ACPI_FAILURE(status)) {
 528                 if (status != AE_NOT_FOUND) {
 529                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
 530                 }
 531                 return -ENODEV;
 532         }
 533
 534         tsd = buffer.pointer;
 535         if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
 536                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
 537                 result = -EFAULT;
 538                 goto end;
 539         }
 540
 541         if (tsd->package.count != 1) {
 542                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
 543                 result = -EFAULT;
 544                 goto end;
 545         }
 546
 547         pdomain = &(pr->throttling.domain_info);
 548
 549         state.length = sizeof(struct acpi_tsd_package);
 550         state.pointer = pdomain;
 551
 552         status = acpi_extract_package(&(tsd->package.elements[0]),
 553                                       &format, &state);
 554         if (ACPI_FAILURE(status)) {
 555                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
 556                 result = -EFAULT;
 557                 goto end;
 558         }
 559
 560         if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
 561                 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
 562                 result = -EFAULT;
 563                 goto end;
 564         }
 565
 566         if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
 567                 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
 568                 result = -EFAULT;
 569                 goto end;
 570         }
 571
 572         pthrottling = &pr->throttling;
 573         pthrottling->tsd_valid_flag = 1;
 574         pthrottling->shared_type = pdomain->coord_type;
 575         cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
 576         /*
 577          * If the coordination type is not defined in ACPI spec,
 578          * the tsd_valid_flag will be clear and coordination type
 579          * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
 580          */
 581         if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
 582                 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
 583                 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
 584                 pthrottling->tsd_valid_flag = 0;
 585                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
 586         }
 587
 588       end:
 589         kfree(buffer.pointer);
 590         return result;
 591 }
 592
 593 /* --------------------------------------------------------------------------
 594                               Throttling Control
 595    -------------------------------------------------------------------------- */
 596 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
 597 {
 598         int state = 0;
 599         u32 value = 0;
 600         u32 duty_mask = 0;
 601         u32 duty_value = 0;
 602
 603         if (!pr)
 604                 return -EINVAL;
 605
 606         if (!pr->flags.throttling)
 607                 return -ENODEV;
 608
 609         pr->throttling.state = 0;
 610
 611         duty_mask = pr->throttling.state_count - 1;
 612
 613         duty_mask <<= pr->throttling.duty_offset;
 614
 615         local_irq_disable();
 616
 617         value = inl(pr->throttling.address);
 618
 619         /*
 620          * Compute the current throttling state when throttling is enabled
 621          * (bit 4 is on).
 622          */
 623         if (value & 0x10) {
 624                 duty_value = value & duty_mask;
 625                 duty_value >>= pr->throttling.duty_offset;
 626
 627                 if (duty_value)
 628                         state = pr->throttling.state_count - duty_value;
 629         }
 630
 631         pr->throttling.state = state;
 632
 633         local_irq_enable();
 634
 635         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 636                           "Throttling state is T%d (%d%% throttling applied)\n",
 637                           state, pr->throttling.states[state].performance));
 638
 639         return 0;
 640 }
 641
 642 #ifdef CONFIG_X86
 643 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
 644                                         acpi_integer * value)
 645 {
 646         struct cpuinfo_x86 *c;
 647         u64 msr_high, msr_low;
 648         unsigned int cpu;
 649         u64 msr = 0;
 650         int ret = -1;
 651
 652         cpu = pr->id;
 653         c = &cpu_data(cpu);
 654
 655         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
 656                 !cpu_has(c, X86_FEATURE_ACPI)) {
 657                 printk(KERN_ERR PREFIX
 658                         "HARDWARE addr space,NOT supported yet\n");
 659         } else {
 660                 msr_low = 0;
 661                 msr_high = 0;
 662                 rdmsr_safe(MSR_IA32_THERM_CONTROL,
 663                         (u32 *)&msr_low , (u32 *) &msr_high);
 664                 msr = (msr_high << 32) | msr_low;
 665                 *value = (acpi_integer) msr;
 666                 ret = 0;
 667         }
 668         return ret;
 669 }
 670
 671 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
 672 {
 673         struct cpuinfo_x86 *c;
 674         unsigned int cpu;
 675         int ret = -1;
 676         u64 msr;
 677
 678         cpu = pr->id;
 679         c = &cpu_data(cpu);
 680
 681         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
 682                 !cpu_has(c, X86_FEATURE_ACPI)) {
 683                 printk(KERN_ERR PREFIX
 684                         "HARDWARE addr space,NOT supported yet\n");
 685         } else {
 686                 msr = value;
 687                 wrmsr_safe(MSR_IA32_THERM_CONTROL,
 688                         msr & 0xffffffff, msr >> 32);
 689                 ret = 0;
 690         }
 691         return ret;
 692 }
 693 #else
 694 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
 695                                 acpi_integer * value)
 696 {
 697         printk(KERN_ERR PREFIX
 698                 "HARDWARE addr space,NOT supported yet\n");
 699         return -1;
 700 }
 701
 702 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
 703 {
 704         printk(KERN_ERR PREFIX
 705                 "HARDWARE addr space,NOT supported yet\n");
 706         return -1;
 707 }
 708 #endif
 709
 710 static int acpi_read_throttling_status(struct acpi_processor *pr,
 711                                         acpi_integer *value)
 712 {
 713         u32 bit_width, bit_offset;
 714         u64 ptc_value;
 715         u64 ptc_mask;
 716         struct acpi_processor_throttling *throttling;
 717         int ret = -1;
 718
 719         throttling = &pr->throttling;
 720         switch (throttling->status_register.space_id) {
 721         case ACPI_ADR_SPACE_SYSTEM_IO:
 722                 ptc_value = 0;
 723                 bit_width = throttling->status_register.bit_width;
 724                 bit_offset = throttling->status_register.bit_offset;
 725
 726                 acpi_os_read_port((acpi_io_address) throttling->status_register.
 727                                   address, (u32 *) &ptc_value,
 728                                   (u32) (bit_width + bit_offset));
 729                 ptc_mask = (1 << bit_width) - 1;
 730                 *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask);
 731                 ret = 0;
 732                 break;
 733         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 734                 ret = acpi_throttling_rdmsr(pr, value);
 735                 break;
 736         default:
 737                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
 738                        (u32) (throttling->status_register.space_id));
 739         }
 740         return ret;
 741 }
 742
 743 static int acpi_write_throttling_state(struct acpi_processor *pr,
 744                                 acpi_integer value)
 745 {
 746         u32 bit_width, bit_offset;
 747         u64 ptc_value;
 748         u64 ptc_mask;
 749         struct acpi_processor_throttling *throttling;
 750         int ret = -1;
 751
 752         throttling = &pr->throttling;
 753         switch (throttling->control_register.space_id) {
 754         case ACPI_ADR_SPACE_SYSTEM_IO:
 755                 bit_width = throttling->control_register.bit_width;
 756                 bit_offset = throttling->control_register.bit_offset;
 757                 ptc_mask = (1 << bit_width) - 1;
 758                 ptc_value = value & ptc_mask;
 759
 760                 acpi_os_write_port((acpi_io_address) throttling->
 761                                         control_register.address,
 762                                         (u32) (ptc_value << bit_offset),
 763                                         (u32) (bit_width + bit_offset));
 764                 ret = 0;
 765                 break;
 766         case ACPI_ADR_SPACE_FIXED_HARDWARE:
 767                 ret = acpi_throttling_wrmsr(pr, value);
 768                 break;
 769         default:
 770                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
 771                        (u32) (throttling->control_register.space_id));
 772         }
 773         return ret;
 774 }
 775
 776 static int acpi_get_throttling_state(struct acpi_processor *pr,
 777                                 acpi_integer value)
 778 {
 779         int i;
 780
 781         for (i = 0; i < pr->throttling.state_count; i++) {
 782                 struct acpi_processor_tx_tss *tx =
 783                     (struct acpi_processor_tx_tss *)&(pr->throttling.
 784                                                       states_tss[i]);
 785                 if (tx->control == value)
 786                         break;
 787         }
 788         if (i > pr->throttling.state_count)
 789                 i = -1;
 790         return i;
 791 }
 792
 793 static int acpi_get_throttling_value(struct acpi_processor *pr,
 794                         int state, acpi_integer *value)
 795 {
 796         int ret = -1;
 797
 798         if (state >= 0 && state <= pr->throttling.state_count) {
 799                 struct acpi_processor_tx_tss *tx =
 800                     (struct acpi_processor_tx_tss *)&(pr->throttling.
 801                                                       states_tss[state]);
 802                 *value = tx->control;
 803                 ret = 0;
 804         }
 805         return ret;
 806 }
 807
 808 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
 809 {
 810         int state = 0;
 811         int ret;
 812         acpi_integer value;
 813
 814         if (!pr)
 815                 return -EINVAL;
 816
 817         if (!pr->flags.throttling)
 818                 return -ENODEV;
 819
 820         pr->throttling.state = 0;
 821
 822         value = 0;
 823         ret = acpi_read_throttling_status(pr, &value);
 824         if (ret >= 0) {
 825                 state = acpi_get_throttling_state(pr, value);
 826                 pr->throttling.state = state;
 827         }
 828
 829         return 0;
 830 }
 831
 832 static int acpi_processor_get_throttling(struct acpi_processor *pr)
 833 {
 834         cpumask_var_t saved_mask;
 835         int ret;
 836
 837         if (!pr)
 838                 return -EINVAL;
 839
 840         if (!pr->flags.throttling)
 841                 return -ENODEV;
 842
 843         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
 844                 return -ENOMEM;
 845
 846         /*
 847          * Migrate task to the cpu pointed by pr.
 848          */
 849         cpumask_copy(saved_mask, &current->cpus_allowed);
 850         /* FIXME: use work_on_cpu() */
 851         set_cpus_allowed_ptr(current, cpumask_of(pr->id));
 852         ret = pr->throttling.acpi_processor_get_throttling(pr);
 853         /* restore the previous state */
 854         set_cpus_allowed_ptr(current, saved_mask);
 855         free_cpumask_var(saved_mask);
 856
 857         return ret;
 858 }
 859
 860 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
 861 {
 862         int i, step;
 863
 864         if (!pr->throttling.address) {
 865                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
 866                 return -EINVAL;
 867         } else if (!pr->throttling.duty_width) {
 868                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
 869                 return -EINVAL;
 870         }
 871         /* TBD: Support duty_cycle values that span bit 4. */
 872         else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
 873                 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
 874                 return -EINVAL;
 875         }
 876
 877         pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
 878
 879         /*
 880          * Compute state values. Note that throttling displays a linear power
 881          * performance relationship (at 50% performance the CPU will consume
 882          * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
 883          */
 884
 885         step = (1000 / pr->throttling.state_count);
 886
 887         for (i = 0; i < pr->throttling.state_count; i++) {
 888                 pr->throttling.states[i].performance = 1000 - step * i;
 889                 pr->throttling.states[i].power = 1000 - step * i;
 890         }
 891         return 0;
 892 }
 893
 894 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
 895                                               int state)
 896 {
 897         u32 value = 0;
 898         u32 duty_mask = 0;
 899         u32 duty_value = 0;
 900
 901         if (!pr)
 902                 return -EINVAL;
 903
 904         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
 905                 return -EINVAL;
 906
 907         if (!pr->flags.throttling)
 908                 return -ENODEV;
 909
 910         if (state == pr->throttling.state)
 911                 return 0;
 912
 913         if (state < pr->throttling_platform_limit)
 914                 return -EPERM;
 915         /*
 916          * Calculate the duty_value and duty_mask.
 917          */
 918         if (state) {
 919                 duty_value = pr->throttling.state_count - state;
 920
 921                 duty_value <<= pr->throttling.duty_offset;
 922
 923                 /* Used to clear all duty_value bits */
 924                 duty_mask = pr->throttling.state_count - 1;
 925
 926                 duty_mask <<= acpi_gbl_FADT.duty_offset;
 927                 duty_mask = ~duty_mask;
 928         }
 929
 930         local_irq_disable();
 931
 932         /*
 933          * Disable throttling by writing a 0 to bit 4.  Note that we must
 934          * turn it off before you can change the duty_value.
 935          */
 936         value = inl(pr->throttling.address);
 937         if (value & 0x10) {
 938                 value &= 0xFFFFFFEF;
 939                 outl(value, pr->throttling.address);
 940         }
 941
 942         /*
 943          * Write the new duty_value and then enable throttling.  Note
 944          * that a state value of 0 leaves throttling disabled.
 945          */
 946         if (state) {
 947                 value &= duty_mask;
 948                 value |= duty_value;
 949                 outl(value, pr->throttling.address);
 950
 951                 value |= 0x00000010;
 952                 outl(value, pr->throttling.address);
 953         }
 954
 955         pr->throttling.state = state;
 956
 957         local_irq_enable();
 958
 959         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 960                           "Throttling state set to T%d (%d%%)\n", state,
 961                           (pr->throttling.states[state].performance ? pr->
 962                            throttling.states[state].performance / 10 : 0)));
 963
 964         return 0;
 965 }
 966
 967 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
 968                                              int state)
 969 {
 970         int ret;
 971         acpi_integer value;
 972
 973         if (!pr)
 974                 return -EINVAL;
 975
 976         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
 977                 return -EINVAL;
 978
 979         if (!pr->flags.throttling)
 980                 return -ENODEV;
 981
 982         if (state == pr->throttling.state)
 983                 return 0;
 984
 985         if (state < pr->throttling_platform_limit)
 986                 return -EPERM;
 987
 988         value = 0;
 989         ret = acpi_get_throttling_value(pr, state, &value);
 990         if (ret >= 0) {
 991                 acpi_write_throttling_state(pr, value);
 992                 pr->throttling.state = state;
 993         }
 994
 995         return 0;
 996 }
 997
 998 int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
 999 {
1000         cpumask_var_t saved_mask;
1001         int ret = 0;
1002         unsigned int i;
1003         struct acpi_processor *match_pr;
1004         struct acpi_processor_throttling *p_throttling;
1005         struct throttling_tstate t_state;
1006         cpumask_var_t online_throttling_cpus;
1007
1008         if (!pr)
1009                 return -EINVAL;
1010
1011         if (!pr->flags.throttling)
1012                 return -ENODEV;
1013
1014         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1015                 return -EINVAL;
1016
1017         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1018                 return -ENOMEM;
1019
1020         if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1021                 free_cpumask_var(saved_mask);
1022                 return -ENOMEM;
1023         }
1024
1025         cpumask_copy(saved_mask, &current->cpus_allowed);
1026         t_state.target_state = state;
1027         p_throttling = &(pr->throttling);
1028         cpumask_and(online_throttling_cpus, cpu_online_mask,
1029                     p_throttling->shared_cpu_map);
1030         /*
1031          * The throttling notifier will be called for every
1032          * affected cpu in order to get one proper T-state.
1033          * The notifier event is THROTTLING_PRECHANGE.
1034          */
1035         for_each_cpu(i, online_throttling_cpus) {
1036                 t_state.cpu = i;
1037                 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1038                                                         &t_state);
1039         }
1040         /*
1041          * The function of acpi_processor_set_throttling will be called
1042          * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1043          * it is necessary to call it for every affected cpu. Otherwise
1044          * it can be called only for the cpu pointed by pr.
1045          */
1046         if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1047                 /* FIXME: use work_on_cpu() */
1048                 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1049                 ret = p_throttling->acpi_processor_set_throttling(pr,
1050                                                 t_state.target_state);
1051         } else {
1052                 /*
1053                  * When the T-state coordination is SW_ALL or HW_ALL,
1054                  * it is necessary to set T-state for every affected
1055                  * cpus.
1056                  */
1057                 for_each_cpu(i, online_throttling_cpus) {
1058                         match_pr = per_cpu(processors, i);
1059                         /*
1060                          * If the pointer is invalid, we will report the
1061                          * error message and continue.
1062                          */
1063                         if (!match_pr) {
1064                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1065                                         "Invalid Pointer for CPU %d\n", i));
1066                                 continue;
1067                         }
1068                         /*
1069                          * If the throttling control is unsupported on CPU i,
1070                          * we will report the error message and continue.
1071                          */
1072                         if (!match_pr->flags.throttling) {
1073                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1074                                         "Throttling Controll is unsupported "
1075                                         "on CPU %d\n", i));
1076                                 continue;
1077                         }
1078                         t_state.cpu = i;
1079                         /* FIXME: use work_on_cpu() */
1080                         set_cpus_allowed_ptr(current, cpumask_of(i));
1081                         ret = match_pr->throttling.
1082                                 acpi_processor_set_throttling(
1083                                 match_pr, t_state.target_state);
1084                 }
1085         }
1086         /*
1087          * After the set_throttling is called, the
1088          * throttling notifier is called for every
1089          * affected cpu to update the T-states.
1090          * The notifier event is THROTTLING_POSTCHANGE
1091          */
1092         for_each_cpu(i, online_throttling_cpus) {
1093                 t_state.cpu = i;
1094                 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1095                                                         &t_state);
1096         }
1097         /* restore the previous state */
1098         /* FIXME: use work_on_cpu() */
1099         set_cpus_allowed_ptr(current, saved_mask);
1100         free_cpumask_var(online_throttling_cpus);
1101         free_cpumask_var(saved_mask);
1102         return ret;
1103 }
1104
1105 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1106 {
1107         int result = 0;
1108         struct acpi_processor_throttling *pthrottling;
1109
1110         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1111                           "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1112                           pr->throttling.address,
1113                           pr->throttling.duty_offset,
1114                           pr->throttling.duty_width));
1115
1116         if (!pr)
1117                 return -EINVAL;
1118
1119         /*
1120          * Evaluate _PTC, _TSS and _TPC
1121          * They must all be present or none of them can be used.
1122          */
1123         if (acpi_processor_get_throttling_control(pr) ||
1124                 acpi_processor_get_throttling_states(pr) ||
1125                 acpi_processor_get_platform_limit(pr))
1126         {
1127                 pr->throttling.acpi_processor_get_throttling =
1128                     &acpi_processor_get_throttling_fadt;
1129                 pr->throttling.acpi_processor_set_throttling =
1130                     &acpi_processor_set_throttling_fadt;
1131                 if (acpi_processor_get_fadt_info(pr))
1132                         return 0;
1133         } else {
1134                 pr->throttling.acpi_processor_get_throttling =
1135                     &acpi_processor_get_throttling_ptc;
1136                 pr->throttling.acpi_processor_set_throttling =
1137                     &acpi_processor_set_throttling_ptc;
1138         }
1139
1140         /*
1141          * If TSD package for one CPU can't be parsed successfully, it means
1142          * that this CPU will have no coordination with other CPUs.
1143          */
1144         if (acpi_processor_get_tsd(pr)) {
1145                 pthrottling = &pr->throttling;
1146                 pthrottling->tsd_valid_flag = 0;
1147                 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1148                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1149         }
1150
1151         /*
1152          * PIIX4 Errata: We don't support throttling on the original PIIX4.
1153          * This shouldn't be an issue as few (if any) mobile systems ever
1154          * used this part.
1155          */
1156         if (errata.piix4.throttle) {
1157                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1158                                   "Throttling not supported on PIIX4 A- or B-step\n"));
1159                 return 0;
1160         }
1161
1162         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1163                           pr->throttling.state_count));
1164
1165         pr->flags.throttling = 1;
1166
1167         /*
1168          * Disable throttling (if enabled).  We'll let subsequent policy (e.g.
1169          * thermal) decide to lower performance if it so chooses, but for now
1170          * we'll crank up the speed.
1171          */
1172
1173         result = acpi_processor_get_throttling(pr);
1174         if (result)
1175                 goto end;
1176
1177         if (pr->throttling.state) {
1178                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1179                                   "Disabling throttling (was T%d)\n",
1180                                   pr->throttling.state));
1181                 result = acpi_processor_set_throttling(pr, 0);
1182                 if (result)
1183                         goto end;
1184         }
1185
1186       end:
1187         if (result)
1188                 pr->flags.throttling = 0;
1189
1190         return result;
1191 }
1192
1193 /* proc interface */
1194
1195 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1196                                               void *offset)
1197 {
1198         struct acpi_processor *pr = seq->private;
1199         int i = 0;
1200         int result = 0;
1201
1202         if (!pr)
1203                 goto end;
1204
1205         if (!(pr->throttling.state_count > 0)) {
1206                 seq_puts(seq, "<not supported>\n");
1207                 goto end;
1208         }
1209
1210         result = acpi_processor_get_throttling(pr);
1211
1212         if (result) {
1213                 seq_puts(seq,
1214                          "Could not determine current throttling state.\n");
1215                 goto end;
1216         }
1217
1218         seq_printf(seq, "state count:             %d\n"
1219                    "active state:            T%d\n"
1220                    "state available: T%d to T%d\n",
1221                    pr->throttling.state_count, pr->throttling.state,
1222                    pr->throttling_platform_limit,
1223                    pr->throttling.state_count - 1);
1224
1225         seq_puts(seq, "states:\n");
1226         if (pr->throttling.acpi_processor_get_throttling ==
1227                         acpi_processor_get_throttling_fadt) {
1228                 for (i = 0; i < pr->throttling.state_count; i++)
1229                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1230                                    (i == pr->throttling.state ? '*' : ' '), i,
1231                                    (pr->throttling.states[i].performance ? pr->
1232                                     throttling.states[i].performance / 10 : 0));
1233         } else {
1234                 for (i = 0; i < pr->throttling.state_count; i++)
1235                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1236                                    (i == pr->throttling.state ? '*' : ' '), i,
1237                                    (int)pr->throttling.states_tss[i].
1238                                    freqpercentage);
1239         }
1240
1241       end:
1242         return 0;
1243 }
1244
1245 static int acpi_processor_throttling_open_fs(struct inode *inode,
1246                                              struct file *file)
1247 {
1248         return single_open(file, acpi_processor_throttling_seq_show,
1249                            PDE(inode)->data);
1250 }
1251
1252 static ssize_t acpi_processor_write_throttling(struct file *file,
1253                                                const char __user * buffer,
1254                                                size_t count, loff_t * data)
1255 {
1256         int result = 0;
1257         struct seq_file *m = file->private_data;
1258         struct acpi_processor *pr = m->private;
1259         char state_string[5] = "";
1260         char *charp = NULL;
1261         size_t state_val = 0;
1262         char tmpbuf[5] = "";
1263
1264         if (!pr || (count > sizeof(state_string) - 1))
1265                 return -EINVAL;
1266
1267         if (copy_from_user(state_string, buffer, count))
1268                 return -EFAULT;
1269
1270         state_string[count] = '\0';
1271         if ((count > 0) && (state_string[count-1] == '\n'))
1272                 state_string[count-1] = '\0';
1273
1274         charp = state_string;
1275         if ((state_string[0] == 't') || (state_string[0] == 'T'))
1276                 charp++;
1277
1278         state_val = simple_strtoul(charp, NULL, 0);
1279         if (state_val >= pr->throttling.state_count)
1280                 return -EINVAL;
1281
1282         snprintf(tmpbuf, 5, "%zu", state_val);
1283
1284         if (strcmp(tmpbuf, charp) != 0)
1285                 return -EINVAL;
1286
1287         result = acpi_processor_set_throttling(pr, state_val);
1288         if (result)
1289                 return result;
1290
1291         return count;
1292 }
1293
1294 struct file_operations acpi_processor_throttling_fops = {
1295         .owner = THIS_MODULE,
1296         .open = acpi_processor_throttling_open_fs,
1297         .read = seq_read,
1298         .write = acpi_processor_write_throttling,
1299         .llseek = seq_lseek,
1300         .release = single_release,
1301 };