drivers/acpi/acpi_processor.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * acpi_processor.c - ACPI processor enumeration support
   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  * Copyright (C) 2013, Intel Corporation
  10  *                     Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  11  */
  12
  13 #include <linux/acpi.h>
  14 #include <linux/device.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/pci.h>
  18
  19 #include <acpi/processor.h>
  20
  21 #include <asm/cpu.h>
  22
  23 #include "internal.h"
  24
  25 #define _COMPONENT      ACPI_PROCESSOR_COMPONENT
  26
  27 ACPI_MODULE_NAME("processor");
  28
  29 DEFINE_PER_CPU(struct acpi_processor *, processors);
  30 EXPORT_PER_CPU_SYMBOL(processors);
  31
  32 /* --------------------------------------------------------------------------
  33                                 Errata Handling
  34    -------------------------------------------------------------------------- */
  35
  36 struct acpi_processor_errata errata __read_mostly;
  37 EXPORT_SYMBOL_GPL(errata);
  38
  39 static int acpi_processor_errata_piix4(struct pci_dev *dev)
  40 {
  41         u8 value1 = 0;
  42         u8 value2 = 0;
  43
  44
  45         if (!dev)
  46                 return -EINVAL;
  47
  48         /*
  49          * Note that 'dev' references the PIIX4 ACPI Controller.
  50          */
  51
  52         switch (dev->revision) {
  53         case 0:
  54                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
  55                 break;
  56         case 1:
  57                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
  58                 break;
  59         case 2:
  60                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
  61                 break;
  62         case 3:
  63                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
  64                 break;
  65         default:
  66                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
  67                 break;
  68         }
  69
  70         switch (dev->revision) {
  71
  72         case 0:         /* PIIX4 A-step */
  73         case 1:         /* PIIX4 B-step */
  74                 /*
  75                  * See specification changes #13 ("Manual Throttle Duty Cycle")
  76                  * and #14 ("Enabling and Disabling Manual Throttle"), plus
  77                  * erratum #5 ("STPCLK# Deassertion Time") from the January
  78                  * 2002 PIIX4 specification update.  Applies to only older
  79                  * PIIX4 models.
  80                  */
  81                 errata.piix4.throttle = 1;
  82                 fallthrough;
  83
  84         case 2:         /* PIIX4E */
  85         case 3:         /* PIIX4M */
  86                 /*
  87                  * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
  88                  * Livelock") from the January 2002 PIIX4 specification update.
  89                  * Applies to all PIIX4 models.
  90                  */
  91
  92                 /*
  93                  * BM-IDE
  94                  * ------
  95                  * Find the PIIX4 IDE Controller and get the Bus Master IDE
  96                  * Status register address.  We'll use this later to read
  97                  * each IDE controller's DMA status to make sure we catch all
  98                  * DMA activity.
  99                  */
 100                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 101                                      PCI_DEVICE_ID_INTEL_82371AB,
 102                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 103                 if (dev) {
 104                         errata.piix4.bmisx = pci_resource_start(dev, 4);
 105                         pci_dev_put(dev);
 106                 }
 107
 108                 /*
 109                  * Type-F DMA
 110                  * ----------
 111                  * Find the PIIX4 ISA Controller and read the Motherboard
 112                  * DMA controller's status to see if Type-F (Fast) DMA mode
 113                  * is enabled (bit 7) on either channel.  Note that we'll
 114                  * disable C3 support if this is enabled, as some legacy
 115                  * devices won't operate well if fast DMA is disabled.
 116                  */
 117                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 118                                      PCI_DEVICE_ID_INTEL_82371AB_0,
 119                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 120                 if (dev) {
 121                         pci_read_config_byte(dev, 0x76, &value1);
 122                         pci_read_config_byte(dev, 0x77, &value2);
 123                         if ((value1 & 0x80) || (value2 & 0x80))
 124                                 errata.piix4.fdma = 1;
 125                         pci_dev_put(dev);
 126                 }
 127
 128                 break;
 129         }
 130
 131         if (errata.piix4.bmisx)
 132                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 133                                   "Bus master activity detection (BM-IDE) erratum enabled\n"));
 134         if (errata.piix4.fdma)
 135                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 136                                   "Type-F DMA livelock erratum (C3 disabled)\n"));
 137
 138         return 0;
 139 }
 140
 141 static int acpi_processor_errata(void)
 142 {
 143         int result = 0;
 144         struct pci_dev *dev = NULL;
 145
 146         /*
 147          * PIIX4
 148          */
 149         dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 150                              PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
 151                              PCI_ANY_ID, NULL);
 152         if (dev) {
 153                 result = acpi_processor_errata_piix4(dev);
 154                 pci_dev_put(dev);
 155         }
 156
 157         return result;
 158 }
 159
 160 /* --------------------------------------------------------------------------
 161                                 Initialization
 162    -------------------------------------------------------------------------- */
 163
 164 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 165 int __weak acpi_map_cpu(acpi_handle handle,
 166                 phys_cpuid_t physid, u32 acpi_id, int *pcpu)
 167 {
 168         return -ENODEV;
 169 }
 170
 171 int __weak acpi_unmap_cpu(int cpu)
 172 {
 173         return -ENODEV;
 174 }
 175
 176 int __weak arch_register_cpu(int cpu)
 177 {
 178         return -ENODEV;
 179 }
 180
 181 void __weak arch_unregister_cpu(int cpu) {}
 182
 183 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
 184 {
 185         unsigned long long sta;
 186         acpi_status status;
 187         int ret;
 188
 189         if (invalid_phys_cpuid(pr->phys_id))
 190                 return -ENODEV;
 191
 192         status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
 193         if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
 194                 return -ENODEV;
 195
 196         cpu_maps_update_begin();
 197         cpu_hotplug_begin();
 198
 199         ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
 200         if (ret)
 201                 goto out;
 202
 203         ret = arch_register_cpu(pr->id);
 204         if (ret) {
 205                 acpi_unmap_cpu(pr->id);
 206                 goto out;
 207         }
 208
 209         /*
 210          * CPU got hot-added, but cpu_data is not initialized yet.  Set a flag
 211          * to delay cpu_idle/throttling initialization and do it when the CPU
 212          * gets online for the first time.
 213          */
 214         pr_info("CPU%d has been hot-added\n", pr->id);
 215         pr->flags.need_hotplug_init = 1;
 216
 217 out:
 218         cpu_hotplug_done();
 219         cpu_maps_update_done();
 220         return ret;
 221 }
 222 #else
 223 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
 224 {
 225         return -ENODEV;
 226 }
 227 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
 228
 229 static int acpi_processor_get_info(struct acpi_device *device)
 230 {
 231         union acpi_object object = { 0 };
 232         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 233         struct acpi_processor *pr = acpi_driver_data(device);
 234         int device_declaration = 0;
 235         acpi_status status = AE_OK;
 236         static int cpu0_initialized;
 237         unsigned long long value;
 238
 239         acpi_processor_errata();
 240
 241         /*
 242          * Check to see if we have bus mastering arbitration control.  This
 243          * is required for proper C3 usage (to maintain cache coherency).
 244          */
 245         if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
 246                 pr->flags.bm_control = 1;
 247                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 248                                   "Bus mastering arbitration control present\n"));
 249         } else
 250                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 251                                   "No bus mastering arbitration control\n"));
 252
 253         if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
 254                 /* Declared with "Processor" statement; match ProcessorID */
 255                 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
 256                 if (ACPI_FAILURE(status)) {
 257                         dev_err(&device->dev,
 258                                 "Failed to evaluate processor object (0x%x)\n",
 259                                 status);
 260                         return -ENODEV;
 261                 }
 262
 263                 pr->acpi_id = object.processor.proc_id;
 264         } else {
 265                 /*
 266                  * Declared with "Device" statement; match _UID.
 267                  */
 268                 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
 269                                                 NULL, &value);
 270                 if (ACPI_FAILURE(status)) {
 271                         dev_err(&device->dev,
 272                                 "Failed to evaluate processor _UID (0x%x)\n",
 273                                 status);
 274                         return -ENODEV;
 275                 }
 276                 device_declaration = 1;
 277                 pr->acpi_id = value;
 278         }
 279
 280         if (acpi_duplicate_processor_id(pr->acpi_id)) {
 281                 if (pr->acpi_id == 0xff)
 282                         dev_info_once(&device->dev,
 283                                 "Entry not well-defined, consider updating BIOS\n");
 284                 else
 285                         dev_err(&device->dev,
 286                                 "Failed to get unique processor _UID (0x%x)\n",
 287                                 pr->acpi_id);
 288                 return -ENODEV;
 289         }
 290
 291         pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
 292                                         pr->acpi_id);
 293         if (invalid_phys_cpuid(pr->phys_id))
 294                 acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
 295
 296         pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
 297         if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
 298                 cpu0_initialized = 1;
 299                 /*
 300                  * Handle UP system running SMP kernel, with no CPU
 301                  * entry in MADT
 302                  */
 303                 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
 304                         pr->id = 0;
 305         }
 306
 307         /*
 308          *  Extra Processor objects may be enumerated on MP systems with
 309          *  less than the max # of CPUs. They should be ignored _iff
 310          *  they are physically not present.
 311          *
 312          *  NOTE: Even if the processor has a cpuid, it may not be present
 313          *  because cpuid <-> apicid mapping is persistent now.
 314          */
 315         if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
 316                 int ret = acpi_processor_hotadd_init(pr);
 317                 if (ret)
 318                         return ret;
 319         }
 320
 321         /*
 322          * On some boxes several processors use the same processor bus id.
 323          * But they are located in different scope. For example:
 324          * \_SB.SCK0.CPU0
 325          * \_SB.SCK1.CPU0
 326          * Rename the processor device bus id. And the new bus id will be
 327          * generated as the following format:
 328          * CPU+CPU ID.
 329          */
 330         sprintf(acpi_device_bid(device), "CPU%X", pr->id);
 331         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
 332                           pr->acpi_id));
 333
 334         if (!object.processor.pblk_address)
 335                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
 336         else if (object.processor.pblk_length != 6)
 337                 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
 338                             object.processor.pblk_length);
 339         else {
 340                 pr->throttling.address = object.processor.pblk_address;
 341                 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
 342                 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
 343
 344                 pr->pblk = object.processor.pblk_address;
 345         }
 346
 347         /*
 348          * If ACPI describes a slot number for this CPU, we can use it to
 349          * ensure we get the right value in the "physical id" field
 350          * of /proc/cpuinfo
 351          */
 352         status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
 353         if (ACPI_SUCCESS(status))
 354                 arch_fix_phys_package_id(pr->id, value);
 355
 356         return 0;
 357 }
 358
 359 /*
 360  * Do not put anything in here which needs the core to be online.
 361  * For example MSR access or setting up things which check for cpuinfo_x86
 362  * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
 363  * Such things have to be put in and set up by the processor driver's .probe().
 364  */
 365 static DEFINE_PER_CPU(void *, processor_device_array);
 366
 367 static int acpi_processor_add(struct acpi_device *device,
 368                                         const struct acpi_device_id *id)
 369 {
 370         struct acpi_processor *pr;
 371         struct device *dev;
 372         int result = 0;
 373
 374         pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
 375         if (!pr)
 376                 return -ENOMEM;
 377
 378         if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
 379                 result = -ENOMEM;
 380                 goto err_free_pr;
 381         }
 382
 383         pr->handle = device->handle;
 384         strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 385         strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
 386         device->driver_data = pr;
 387
 388         result = acpi_processor_get_info(device);
 389         if (result) /* Processor is not physically present or unavailable */
 390                 return 0;
 391
 392         BUG_ON(pr->id >= nr_cpu_ids);
 393
 394         /*
 395          * Buggy BIOS check.
 396          * ACPI id of processors can be reported wrongly by the BIOS.
 397          * Don't trust it blindly
 398          */
 399         if (per_cpu(processor_device_array, pr->id) != NULL &&
 400             per_cpu(processor_device_array, pr->id) != device) {
 401                 dev_warn(&device->dev,
 402                         "BIOS reported wrong ACPI id %d for the processor\n",
 403                         pr->id);
 404                 /* Give up, but do not abort the namespace scan. */
 405                 goto err;
 406         }
 407         /*
 408          * processor_device_array is not cleared on errors to allow buggy BIOS
 409          * checks.
 410          */
 411         per_cpu(processor_device_array, pr->id) = device;
 412         per_cpu(processors, pr->id) = pr;
 413
 414         dev = get_cpu_device(pr->id);
 415         if (!dev) {
 416                 result = -ENODEV;
 417                 goto err;
 418         }
 419
 420         result = acpi_bind_one(dev, device);
 421         if (result)
 422                 goto err;
 423
 424         pr->dev = dev;
 425
 426         /* Trigger the processor driver's .probe() if present. */
 427         if (device_attach(dev) >= 0)
 428                 return 1;
 429
 430         dev_err(dev, "Processor driver could not be attached\n");
 431         acpi_unbind_one(dev);
 432
 433  err:
 434         free_cpumask_var(pr->throttling.shared_cpu_map);
 435         device->driver_data = NULL;
 436         per_cpu(processors, pr->id) = NULL;
 437  err_free_pr:
 438         kfree(pr);
 439         return result;
 440 }
 441
 442 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 443 /* --------------------------------------------------------------------------
 444                                     Removal
 445    -------------------------------------------------------------------------- */
 446
 447 static void acpi_processor_remove(struct acpi_device *device)
 448 {
 449         struct acpi_processor *pr;
 450
 451         if (!device || !acpi_driver_data(device))
 452                 return;
 453
 454         pr = acpi_driver_data(device);
 455         if (pr->id >= nr_cpu_ids)
 456                 goto out;
 457
 458         /*
 459          * The only reason why we ever get here is CPU hot-removal.  The CPU is
 460          * already offline and the ACPI device removal locking prevents it from
 461          * being put back online at this point.
 462          *
 463          * Unbind the driver from the processor device and detach it from the
 464          * ACPI companion object.
 465          */
 466         device_release_driver(pr->dev);
 467         acpi_unbind_one(pr->dev);
 468
 469         /* Clean up. */
 470         per_cpu(processor_device_array, pr->id) = NULL;
 471         per_cpu(processors, pr->id) = NULL;
 472
 473         cpu_maps_update_begin();
 474         cpu_hotplug_begin();
 475
 476         /* Remove the CPU. */
 477         arch_unregister_cpu(pr->id);
 478         acpi_unmap_cpu(pr->id);
 479
 480         cpu_hotplug_done();
 481         cpu_maps_update_done();
 482
 483         try_offline_node(cpu_to_node(pr->id));
 484
 485  out:
 486         free_cpumask_var(pr->throttling.shared_cpu_map);
 487         kfree(pr);
 488 }
 489 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
 490
 491 #ifdef CONFIG_X86
 492 static bool acpi_hwp_native_thermal_lvt_set;
 493 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
 494                                                           u32 lvl,
 495                                                           void *context,
 496                                                           void **rv)
 497 {
 498         u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
 499         u32 capbuf[2];
 500         struct acpi_osc_context osc_context = {
 501                 .uuid_str = sb_uuid_str,
 502                 .rev = 1,
 503                 .cap.length = 8,
 504                 .cap.pointer = capbuf,
 505         };
 506
 507         if (acpi_hwp_native_thermal_lvt_set)
 508                 return AE_CTRL_TERMINATE;
 509
 510         capbuf[0] = 0x0000;
 511         capbuf[1] = 0x1000; /* set bit 12 */
 512
 513         if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
 514                 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
 515                         u32 *capbuf_ret = osc_context.ret.pointer;
 516
 517                         if (capbuf_ret[1] & 0x1000) {
 518                                 acpi_handle_info(handle,
 519                                         "_OSC native thermal LVT Acked\n");
 520                                 acpi_hwp_native_thermal_lvt_set = true;
 521                         }
 522                 }
 523                 kfree(osc_context.ret.pointer);
 524         }
 525
 526         return AE_OK;
 527 }
 528
 529 void __init acpi_early_processor_osc(void)
 530 {
 531         if (boot_cpu_has(X86_FEATURE_HWP)) {
 532                 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 533                                     ACPI_UINT32_MAX,
 534                                     acpi_hwp_native_thermal_lvt_osc,
 535                                     NULL, NULL, NULL);
 536                 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
 537                                  acpi_hwp_native_thermal_lvt_osc,
 538                                  NULL, NULL);
 539         }
 540 }
 541 #endif
 542
 543 /*
 544  * The following ACPI IDs are known to be suitable for representing as
 545  * processor devices.
 546  */
 547 static const struct acpi_device_id processor_device_ids[] = {
 548
 549         { ACPI_PROCESSOR_OBJECT_HID, },
 550         { ACPI_PROCESSOR_DEVICE_HID, },
 551
 552         { }
 553 };
 554
 555 static struct acpi_scan_handler processor_handler = {
 556         .ids = processor_device_ids,
 557         .attach = acpi_processor_add,
 558 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 559         .detach = acpi_processor_remove,
 560 #endif
 561         .hotplug = {
 562                 .enabled = true,
 563         },
 564 };
 565
 566 static int acpi_processor_container_attach(struct acpi_device *dev,
 567                                            const struct acpi_device_id *id)
 568 {
 569         return 1;
 570 }
 571
 572 static const struct acpi_device_id processor_container_ids[] = {
 573         { ACPI_PROCESSOR_CONTAINER_HID, },
 574         { }
 575 };
 576
 577 static struct acpi_scan_handler processor_container_handler = {
 578         .ids = processor_container_ids,
 579         .attach = acpi_processor_container_attach,
 580 };
 581
 582 /* The number of the unique processor IDs */
 583 static int nr_unique_ids __initdata;
 584
 585 /* The number of the duplicate processor IDs */
 586 static int nr_duplicate_ids;
 587
 588 /* Used to store the unique processor IDs */
 589 static int unique_processor_ids[] __initdata = {
 590         [0 ... NR_CPUS - 1] = -1,
 591 };
 592
 593 /* Used to store the duplicate processor IDs */
 594 static int duplicate_processor_ids[] = {
 595         [0 ... NR_CPUS - 1] = -1,
 596 };
 597
 598 static void __init processor_validated_ids_update(int proc_id)
 599 {
 600         int i;
 601
 602         if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
 603                 return;
 604
 605         /*
 606          * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
 607          * already in the IDs, do nothing.
 608          */
 609         for (i = 0; i < nr_duplicate_ids; i++) {
 610                 if (duplicate_processor_ids[i] == proc_id)
 611                         return;
 612         }
 613
 614         /*
 615          * Secondly, compare the proc_id with unique IDs, if the proc_id is in
 616          * the IDs, put it in the duplicate IDs.
 617          */
 618         for (i = 0; i < nr_unique_ids; i++) {
 619                 if (unique_processor_ids[i] == proc_id) {
 620                         duplicate_processor_ids[nr_duplicate_ids] = proc_id;
 621                         nr_duplicate_ids++;
 622                         return;
 623                 }
 624         }
 625
 626         /*
 627          * Lastly, the proc_id is a unique ID, put it in the unique IDs.
 628          */
 629         unique_processor_ids[nr_unique_ids] = proc_id;
 630         nr_unique_ids++;
 631 }
 632
 633 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
 634                                                   u32 lvl,
 635                                                   void *context,
 636                                                   void **rv)
 637 {
 638         acpi_status status;
 639         acpi_object_type acpi_type;
 640         unsigned long long uid;
 641         union acpi_object object = { 0 };
 642         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 643
 644         status = acpi_get_type(handle, &acpi_type);
 645         if (ACPI_FAILURE(status))
 646                 return status;
 647
 648         switch (acpi_type) {
 649         case ACPI_TYPE_PROCESSOR:
 650                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 651                 if (ACPI_FAILURE(status))
 652                         goto err;
 653                 uid = object.processor.proc_id;
 654                 break;
 655
 656         case ACPI_TYPE_DEVICE:
 657                 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
 658                 if (ACPI_FAILURE(status))
 659                         goto err;
 660                 break;
 661         default:
 662                 goto err;
 663         }
 664
 665         processor_validated_ids_update(uid);
 666         return AE_OK;
 667
 668 err:
 669         /* Exit on error, but don't abort the namespace walk */
 670         acpi_handle_info(handle, "Invalid processor object\n");
 671         return AE_OK;
 672
 673 }
 674
 675 static void __init acpi_processor_check_duplicates(void)
 676 {
 677         /* check the correctness for all processors in ACPI namespace */
 678         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 679                                                 ACPI_UINT32_MAX,
 680                                                 acpi_processor_ids_walk,
 681                                                 NULL, NULL, NULL);
 682         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
 683                                                 NULL, NULL);
 684 }
 685
 686 bool acpi_duplicate_processor_id(int proc_id)
 687 {
 688         int i;
 689
 690         /*
 691          * compare the proc_id with duplicate IDs, if the proc_id is already
 692          * in the duplicate IDs, return true, otherwise, return false.
 693          */
 694         for (i = 0; i < nr_duplicate_ids; i++) {
 695                 if (duplicate_processor_ids[i] == proc_id)
 696                         return true;
 697         }
 698         return false;
 699 }
 700
 701 void __init acpi_processor_init(void)
 702 {
 703         acpi_processor_check_duplicates();
 704         acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
 705         acpi_scan_add_handler(&processor_container_handler);
 706 }
 707
 708 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
 709 /**
 710  * acpi_processor_claim_cst_control - Request _CST control from the platform.
 711  */
 712 bool acpi_processor_claim_cst_control(void)
 713 {
 714         static bool cst_control_claimed;
 715         acpi_status status;
 716
 717         if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
 718                 return true;
 719
 720         status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
 721                                     acpi_gbl_FADT.cst_control, 8);
 722         if (ACPI_FAILURE(status)) {
 723                 pr_warn("ACPI: Failed to claim processor _CST control\n");
 724                 return false;
 725         }
 726
 727         cst_control_claimed = true;
 728         return true;
 729 }
 730 EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
 731
 732 /**
 733  * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
 734  * @handle: ACPI handle of the processor object containing the _CST.
 735  * @cpu: The numeric ID of the target CPU.
 736  * @info: Object write the C-states information into.
 737  *
 738  * Extract the C-state information for the given CPU from the output of the _CST
 739  * control method under the corresponding ACPI processor object (or processor
 740  * device object) and populate @info with it.
 741  *
 742  * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
 743  * acpi_processor_ffh_cstate_probe() to verify them and update the
 744  * cpu_cstate_entry data for @cpu.
 745  */
 746 int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
 747                                 struct acpi_processor_power *info)
 748 {
 749         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 750         union acpi_object *cst;
 751         acpi_status status;
 752         u64 count;
 753         int last_index = 0;
 754         int i, ret = 0;
 755
 756         status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
 757         if (ACPI_FAILURE(status)) {
 758                 acpi_handle_debug(handle, "No _CST\n");
 759                 return -ENODEV;
 760         }
 761
 762         cst = buffer.pointer;
 763
 764         /* There must be at least 2 elements. */
 765         if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
 766                 acpi_handle_warn(handle, "Invalid _CST output\n");
 767                 ret = -EFAULT;
 768                 goto end;
 769         }
 770
 771         count = cst->package.elements[0].integer.value;
 772
 773         /* Validate the number of C-states. */
 774         if (count < 1 || count != cst->package.count - 1) {
 775                 acpi_handle_warn(handle, "Inconsistent _CST data\n");
 776                 ret = -EFAULT;
 777                 goto end;
 778         }
 779
 780         for (i = 1; i <= count; i++) {
 781                 union acpi_object *element;
 782                 union acpi_object *obj;
 783                 struct acpi_power_register *reg;
 784                 struct acpi_processor_cx cx;
 785
 786                 /*
 787                  * If there is not enough space for all C-states, skip the
 788                  * excess ones and log a warning.
 789                  */
 790                 if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
 791                         acpi_handle_warn(handle,
 792                                          "No room for more idle states (limit: %d)\n",
 793                                          ACPI_PROCESSOR_MAX_POWER - 1);
 794                         break;
 795                 }
 796
 797                 memset(&cx, 0, sizeof(cx));
 798
 799                 element = &cst->package.elements[i];
 800                 if (element->type != ACPI_TYPE_PACKAGE) {
 801                         acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
 802                                          i, element->type);
 803                         continue;
 804                 }
 805
 806                 if (element->package.count != 4) {
 807                         acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
 808                                          i, element->package.count);
 809                         continue;
 810                 }
 811
 812                 obj = &element->package.elements[0];
 813
 814                 if (obj->type != ACPI_TYPE_BUFFER) {
 815                         acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
 816                                          i, obj->type);
 817                         continue;
 818                 }
 819
 820                 reg = (struct acpi_power_register *)obj->buffer.pointer;
 821
 822                 obj = &element->package.elements[1];
 823                 if (obj->type != ACPI_TYPE_INTEGER) {
 824                         acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
 825                                          i, obj->type);
 826                         continue;
 827                 }
 828
 829                 cx.type = obj->integer.value;
 830                 /*
 831                  * There are known cases in which the _CST output does not
 832                  * contain C1, so if the type of the first state found is not
 833                  * C1, leave an empty slot for C1 to be filled in later.
 834                  */
 835                 if (i == 1 && cx.type != ACPI_STATE_C1)
 836                         last_index = 1;
 837
 838                 cx.address = reg->address;
 839                 cx.index = last_index + 1;
 840
 841                 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
 842                         if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
 843                                 /*
 844                                  * In the majority of cases _CST describes C1 as
 845                                  * a FIXED_HARDWARE C-state, but if the command
 846                                  * line forbids using MWAIT, use CSTATE_HALT for
 847                                  * C1 regardless.
 848                                  */
 849                                 if (cx.type == ACPI_STATE_C1 &&
 850                                     boot_option_idle_override == IDLE_NOMWAIT) {
 851                                         cx.entry_method = ACPI_CSTATE_HALT;
 852                                         snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
 853                                 } else {
 854                                         cx.entry_method = ACPI_CSTATE_FFH;
 855                                 }
 856                         } else if (cx.type == ACPI_STATE_C1) {
 857                                 /*
 858                                  * In the special case of C1, FIXED_HARDWARE can
 859                                  * be handled by executing the HLT instruction.
 860                                  */
 861                                 cx.entry_method = ACPI_CSTATE_HALT;
 862                                 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
 863                         } else {
 864                                 acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
 865                                                  i);
 866                                 continue;
 867                         }
 868                 } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
 869                         cx.entry_method = ACPI_CSTATE_SYSTEMIO;
 870                         snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
 871                                  cx.address);
 872                 } else {
 873                         acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
 874                                          i, reg->space_id);
 875                         continue;
 876                 }
 877
 878                 if (cx.type == ACPI_STATE_C1)
 879                         cx.valid = 1;
 880
 881                 obj = &element->package.elements[2];
 882                 if (obj->type != ACPI_TYPE_INTEGER) {
 883                         acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
 884                                          i, obj->type);
 885                         continue;
 886                 }
 887
 888                 cx.latency = obj->integer.value;
 889
 890                 obj = &element->package.elements[3];
 891                 if (obj->type != ACPI_TYPE_INTEGER) {
 892                         acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
 893                                          i, obj->type);
 894                         continue;
 895                 }
 896
 897                 memcpy(&info->states[++last_index], &cx, sizeof(cx));
 898         }
 899
 900         acpi_handle_info(handle, "Found %d idle states\n", last_index);
 901
 902         info->count = last_index;
 903
 904       end:
 905         kfree(buffer.pointer);
 906
 907         return ret;
 908 }
 909 EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
 910 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */