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 <[email protected]>
   6  * Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
   7  * Copyright (C) 2004       Dominik Brodowski <[email protected]>
   8  * Copyright (C) 2004  Anil S Keshavamurthy <[email protected]>
   9  * Copyright (C) 2013, Intel Corporation
  10  *                     Rafael J. Wysocki <[email protected]>
  11  */
  12 #define pr_fmt(fmt) "ACPI: " fmt
  13
  14 #include <linux/acpi.h>
  15 #include <linux/cpu.h>
  16 #include <linux/device.h>
  17 #include <linux/dmi.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/pci.h>
  21 #include <linux/platform_device.h>
  22
  23 #include <acpi/processor.h>
  24
  25 #include <asm/cpu.h>
  26
  27 #include <xen/xen.h>
  28
  29 #include "internal.h"
  30
  31 DEFINE_PER_CPU(struct acpi_processor *, processors);
  32 EXPORT_PER_CPU_SYMBOL(processors);
  33
  34 /* Errata Handling */
  35 struct acpi_processor_errata errata __read_mostly;
  36 EXPORT_SYMBOL_GPL(errata);
  37
  38 acpi_handle acpi_get_processor_handle(int cpu)
  39 {
  40         struct acpi_processor *pr;
  41
  42         pr = per_cpu(processors, cpu);
  43         if (pr)
  44                 return pr->handle;
  45
  46         return NULL;
  47 }
  48
  49 static int acpi_processor_errata_piix4(struct pci_dev *dev)
  50 {
  51         u8 value1 = 0;
  52         u8 value2 = 0;
  53
  54
  55         if (!dev)
  56                 return -EINVAL;
  57
  58         /*
  59          * Note that 'dev' references the PIIX4 ACPI Controller.
  60          */
  61
  62         switch (dev->revision) {
  63         case 0:
  64                 dev_dbg(&dev->dev, "Found PIIX4 A-step\n");
  65                 break;
  66         case 1:
  67                 dev_dbg(&dev->dev, "Found PIIX4 B-step\n");
  68                 break;
  69         case 2:
  70                 dev_dbg(&dev->dev, "Found PIIX4E\n");
  71                 break;
  72         case 3:
  73                 dev_dbg(&dev->dev, "Found PIIX4M\n");
  74                 break;
  75         default:
  76                 dev_dbg(&dev->dev, "Found unknown PIIX4\n");
  77                 break;
  78         }
  79
  80         switch (dev->revision) {
  81
  82         case 0:         /* PIIX4 A-step */
  83         case 1:         /* PIIX4 B-step */
  84                 /*
  85                  * See specification changes #13 ("Manual Throttle Duty Cycle")
  86                  * and #14 ("Enabling and Disabling Manual Throttle"), plus
  87                  * erratum #5 ("STPCLK# Deassertion Time") from the January
  88                  * 2002 PIIX4 specification update.  Applies to only older
  89                  * PIIX4 models.
  90                  */
  91                 errata.piix4.throttle = 1;
  92                 fallthrough;
  93
  94         case 2:         /* PIIX4E */
  95         case 3:         /* PIIX4M */
  96                 /*
  97                  * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
  98                  * Livelock") from the January 2002 PIIX4 specification update.
  99                  * Applies to all PIIX4 models.
 100                  */
 101
 102                 /*
 103                  * BM-IDE
 104                  * ------
 105                  * Find the PIIX4 IDE Controller and get the Bus Master IDE
 106                  * Status register address.  We'll use this later to read
 107                  * each IDE controller's DMA status to make sure we catch all
 108                  * DMA activity.
 109                  */
 110                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 111                                      PCI_DEVICE_ID_INTEL_82371AB,
 112                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 113                 if (dev) {
 114                         errata.piix4.bmisx = pci_resource_start(dev, 4);
 115                         pci_dev_put(dev);
 116                 }
 117
 118                 /*
 119                  * Type-F DMA
 120                  * ----------
 121                  * Find the PIIX4 ISA Controller and read the Motherboard
 122                  * DMA controller's status to see if Type-F (Fast) DMA mode
 123                  * is enabled (bit 7) on either channel.  Note that we'll
 124                  * disable C3 support if this is enabled, as some legacy
 125                  * devices won't operate well if fast DMA is disabled.
 126                  */
 127                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 128                                      PCI_DEVICE_ID_INTEL_82371AB_0,
 129                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 130                 if (dev) {
 131                         pci_read_config_byte(dev, 0x76, &value1);
 132                         pci_read_config_byte(dev, 0x77, &value2);
 133                         if ((value1 & 0x80) || (value2 & 0x80))
 134                                 errata.piix4.fdma = 1;
 135                         pci_dev_put(dev);
 136                 }
 137
 138                 break;
 139         }
 140
 141         if (errata.piix4.bmisx)
 142                 dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");
 143         if (errata.piix4.fdma)
 144                 dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");
 145
 146         return 0;
 147 }
 148
 149 static int acpi_processor_errata(void)
 150 {
 151         int result = 0;
 152         struct pci_dev *dev = NULL;
 153
 154         /*
 155          * PIIX4
 156          */
 157         dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 158                              PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
 159                              PCI_ANY_ID, NULL);
 160         if (dev) {
 161                 result = acpi_processor_errata_piix4(dev);
 162                 pci_dev_put(dev);
 163         }
 164
 165         return result;
 166 }
 167
 168 /* Create a platform device to represent a CPU frequency control mechanism. */
 169 static void cpufreq_add_device(const char *name)
 170 {
 171         struct platform_device *pdev;
 172
 173         pdev = platform_device_register_simple(name, PLATFORM_DEVID_NONE, NULL, 0);
 174         if (IS_ERR(pdev))
 175                 pr_info("%s device creation failed: %pe\n", name, pdev);
 176 }
 177
 178 #ifdef CONFIG_X86
 179 /* Check presence of Processor Clocking Control by searching for \_SB.PCCH. */
 180 static void __init acpi_pcc_cpufreq_init(void)
 181 {
 182         acpi_status status;
 183         acpi_handle handle;
 184
 185         status = acpi_get_handle(NULL, "\\_SB", &handle);
 186         if (ACPI_FAILURE(status))
 187                 return;
 188
 189         if (acpi_has_method(handle, "PCCH"))
 190                 cpufreq_add_device("pcc-cpufreq");
 191 }
 192 #else
 193 static void __init acpi_pcc_cpufreq_init(void) {}
 194 #endif /* CONFIG_X86 */
 195
 196 /* Initialization */
 197 static DEFINE_PER_CPU(void *, processor_device_array);
 198
 199 static int acpi_processor_set_per_cpu(struct acpi_processor *pr,
 200                                       struct acpi_device *device)
 201 {
 202         BUG_ON(pr->id >= nr_cpu_ids);
 203
 204         /*
 205          * Buggy BIOS check.
 206          * ACPI id of processors can be reported wrongly by the BIOS.
 207          * Don't trust it blindly
 208          */
 209         if (per_cpu(processor_device_array, pr->id) != NULL &&
 210             per_cpu(processor_device_array, pr->id) != device) {
 211                 dev_warn(&device->dev,
 212                          "BIOS reported wrong ACPI id %d for the processor\n",
 213                          pr->id);
 214                 return -EINVAL;
 215         }
 216         /*
 217          * processor_device_array is not cleared on errors to allow buggy BIOS
 218          * checks.
 219          */
 220         per_cpu(processor_device_array, pr->id) = device;
 221         per_cpu(processors, pr->id) = pr;
 222
 223         return 0;
 224 }
 225
 226 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 227 static int acpi_processor_hotadd_init(struct acpi_processor *pr,
 228                                       struct acpi_device *device)
 229 {
 230         int ret;
 231
 232         if (invalid_phys_cpuid(pr->phys_id))
 233                 return -ENODEV;
 234
 235         cpu_maps_update_begin();
 236         cpus_write_lock();
 237
 238         ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
 239         if (ret)
 240                 goto out;
 241
 242         ret = acpi_processor_set_per_cpu(pr, device);
 243         if (ret) {
 244                 acpi_unmap_cpu(pr->id);
 245                 goto out;
 246         }
 247
 248         ret = arch_register_cpu(pr->id);
 249         if (ret) {
 250                 /* Leave the processor device array in place to detect buggy bios */
 251                 per_cpu(processors, pr->id) = NULL;
 252                 acpi_unmap_cpu(pr->id);
 253                 goto out;
 254         }
 255
 256         /*
 257          * CPU got hot-added, but cpu_data is not initialized yet. Do
 258          * cpu_idle/throttling initialization when the CPU gets online for
 259          * the first time.
 260          */
 261         pr_info("CPU%d has been hot-added\n", pr->id);
 262
 263 out:
 264         cpus_write_unlock();
 265         cpu_maps_update_done();
 266         return ret;
 267 }
 268 #else
 269 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,
 270                                              struct acpi_device *device)
 271 {
 272         return -ENODEV;
 273 }
 274 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
 275
 276 static int acpi_processor_get_info(struct acpi_device *device)
 277 {
 278         union acpi_object object = { 0 };
 279         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 280         struct acpi_processor *pr = acpi_driver_data(device);
 281         int device_declaration = 0;
 282         acpi_status status = AE_OK;
 283         static int cpu0_initialized;
 284         unsigned long long value;
 285         int ret;
 286
 287         acpi_processor_errata();
 288
 289         /*
 290          * Check to see if we have bus mastering arbitration control.  This
 291          * is required for proper C3 usage (to maintain cache coherency).
 292          */
 293         if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
 294                 pr->flags.bm_control = 1;
 295                 dev_dbg(&device->dev, "Bus mastering arbitration control present\n");
 296         } else
 297                 dev_dbg(&device->dev, "No bus mastering arbitration control\n");
 298
 299         if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
 300                 /* Declared with "Processor" statement; match ProcessorID */
 301                 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
 302                 if (ACPI_FAILURE(status)) {
 303                         dev_err(&device->dev,
 304                                 "Failed to evaluate processor object (0x%x)\n",
 305                                 status);
 306                         return -ENODEV;
 307                 }
 308
 309                 pr->acpi_id = object.processor.proc_id;
 310         } else {
 311                 /*
 312                  * Declared with "Device" statement; match _UID.
 313                  */
 314                 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
 315                                                 NULL, &value);
 316                 if (ACPI_FAILURE(status)) {
 317                         dev_err(&device->dev,
 318                                 "Failed to evaluate processor _UID (0x%x)\n",
 319                                 status);
 320                         return -ENODEV;
 321                 }
 322                 device_declaration = 1;
 323                 pr->acpi_id = value;
 324         }
 325
 326         if (acpi_duplicate_processor_id(pr->acpi_id)) {
 327                 if (pr->acpi_id == 0xff)
 328                         dev_info_once(&device->dev,
 329                                 "Entry not well-defined, consider updating BIOS\n");
 330                 else
 331                         dev_err(&device->dev,
 332                                 "Failed to get unique processor _UID (0x%x)\n",
 333                                 pr->acpi_id);
 334                 return -ENODEV;
 335         }
 336
 337         pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
 338                                         pr->acpi_id);
 339         if (invalid_phys_cpuid(pr->phys_id))
 340                 dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");
 341
 342         pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
 343         if (!cpu0_initialized) {
 344                 cpu0_initialized = 1;
 345                 /*
 346                  * Handle UP system running SMP kernel, with no CPU
 347                  * entry in MADT
 348                  */
 349                 if (!acpi_has_cpu_in_madt() && invalid_logical_cpuid(pr->id) &&
 350                     (num_online_cpus() == 1))
 351                         pr->id = 0;
 352                 /*
 353                  * Check availability of Processor Performance Control by
 354                  * looking at the presence of the _PCT object under the first
 355                  * processor definition.
 356                  */
 357                 if (acpi_has_method(pr->handle, "_PCT"))
 358                         cpufreq_add_device("acpi-cpufreq");
 359         }
 360
 361         /*
 362          *  This code is not called unless we know the CPU is present and
 363          *  enabled. The two paths are:
 364          *  a) Initially present CPUs on architectures that do not defer
 365          *     their arch_register_cpu() calls until this point.
 366          *  b) Hotplugged CPUs (enabled bit in _STA has transitioned from not
 367          *     enabled to enabled)
 368          */
 369         if (!get_cpu_device(pr->id))
 370                 ret = acpi_processor_hotadd_init(pr, device);
 371         else
 372                 ret = acpi_processor_set_per_cpu(pr, device);
 373         if (ret)
 374                 return ret;
 375
 376         /*
 377          * On some boxes several processors use the same processor bus id.
 378          * But they are located in different scope. For example:
 379          * \_SB.SCK0.CPU0
 380          * \_SB.SCK1.CPU0
 381          * Rename the processor device bus id. And the new bus id will be
 382          * generated as the following format:
 383          * CPU+CPU ID.
 384          */
 385         sprintf(acpi_device_bid(device), "CPU%X", pr->id);
 386         dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);
 387
 388         if (!object.processor.pblk_address)
 389                 dev_dbg(&device->dev, "No PBLK (NULL address)\n");
 390         else if (object.processor.pblk_length != 6)
 391                 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
 392                             object.processor.pblk_length);
 393         else {
 394                 pr->throttling.address = object.processor.pblk_address;
 395                 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
 396                 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
 397
 398                 pr->pblk = object.processor.pblk_address;
 399         }
 400
 401         /*
 402          * If ACPI describes a slot number for this CPU, we can use it to
 403          * ensure we get the right value in the "physical id" field
 404          * of /proc/cpuinfo
 405          */
 406         status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
 407         if (ACPI_SUCCESS(status))
 408                 arch_fix_phys_package_id(pr->id, value);
 409
 410         return 0;
 411 }
 412
 413 /*
 414  * Do not put anything in here which needs the core to be online.
 415  * For example MSR access or setting up things which check for cpuinfo_x86
 416  * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
 417  * Such things have to be put in and set up by the processor driver's .probe().
 418  */
 419 static int acpi_processor_add(struct acpi_device *device,
 420                                         const struct acpi_device_id *id)
 421 {
 422         struct acpi_processor *pr;
 423         struct device *dev;
 424         int result = 0;
 425
 426         if (!acpi_device_is_enabled(device))
 427                 return -ENODEV;
 428
 429         pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
 430         if (!pr)
 431                 return -ENOMEM;
 432
 433         if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
 434                 result = -ENOMEM;
 435                 goto err_free_pr;
 436         }
 437
 438         pr->handle = device->handle;
 439         strscpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 440         strscpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
 441         device->driver_data = pr;
 442
 443         result = acpi_processor_get_info(device);
 444         if (result) /* Processor is not physically present or unavailable */
 445                 goto err_clear_driver_data;
 446
 447         dev = get_cpu_device(pr->id);
 448         if (!dev) {
 449                 result = -ENODEV;
 450                 goto err_clear_per_cpu;
 451         }
 452
 453         result = acpi_bind_one(dev, device);
 454         if (result)
 455                 goto err_clear_per_cpu;
 456
 457         pr->dev = dev;
 458
 459         /* Trigger the processor driver's .probe() if present. */
 460         if (device_attach(dev) >= 0)
 461                 return 1;
 462
 463         dev_err(dev, "Processor driver could not be attached\n");
 464         acpi_unbind_one(dev);
 465
 466  err_clear_per_cpu:
 467         per_cpu(processors, pr->id) = NULL;
 468  err_clear_driver_data:
 469         device->driver_data = NULL;
 470         free_cpumask_var(pr->throttling.shared_cpu_map);
 471  err_free_pr:
 472         kfree(pr);
 473         return result;
 474 }
 475
 476 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 477 /* Removal */
 478 static void acpi_processor_post_eject(struct acpi_device *device)
 479 {
 480         struct acpi_processor *pr;
 481
 482         if (!device || !acpi_driver_data(device))
 483                 return;
 484
 485         pr = acpi_driver_data(device);
 486         if (pr->id >= nr_cpu_ids)
 487                 goto out;
 488
 489         /*
 490          * The only reason why we ever get here is CPU hot-removal.  The CPU is
 491          * already offline and the ACPI device removal locking prevents it from
 492          * being put back online at this point.
 493          *
 494          * Unbind the driver from the processor device and detach it from the
 495          * ACPI companion object.
 496          */
 497         device_release_driver(pr->dev);
 498         acpi_unbind_one(pr->dev);
 499
 500         cpu_maps_update_begin();
 501         cpus_write_lock();
 502
 503         /* Remove the CPU. */
 504         arch_unregister_cpu(pr->id);
 505         acpi_unmap_cpu(pr->id);
 506
 507         /* Clean up. */
 508         per_cpu(processor_device_array, pr->id) = NULL;
 509         per_cpu(processors, pr->id) = NULL;
 510
 511         cpus_write_unlock();
 512         cpu_maps_update_done();
 513
 514         try_offline_node(cpu_to_node(pr->id));
 515
 516  out:
 517         free_cpumask_var(pr->throttling.shared_cpu_map);
 518         kfree(pr);
 519 }
 520 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
 521
 522 #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
 523 bool __init processor_physically_present(acpi_handle handle)
 524 {
 525         int cpuid, type;
 526         u32 acpi_id;
 527         acpi_status status;
 528         acpi_object_type acpi_type;
 529         unsigned long long tmp;
 530         union acpi_object object = {};
 531         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 532
 533         status = acpi_get_type(handle, &acpi_type);
 534         if (ACPI_FAILURE(status))
 535                 return false;
 536
 537         switch (acpi_type) {
 538         case ACPI_TYPE_PROCESSOR:
 539                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 540                 if (ACPI_FAILURE(status))
 541                         return false;
 542                 acpi_id = object.processor.proc_id;
 543                 break;
 544         case ACPI_TYPE_DEVICE:
 545                 status = acpi_evaluate_integer(handle, METHOD_NAME__UID,
 546                                                NULL, &tmp);
 547                 if (ACPI_FAILURE(status))
 548                         return false;
 549                 acpi_id = tmp;
 550                 break;
 551         default:
 552                 return false;
 553         }
 554
 555         if (xen_initial_domain())
 556                 /*
 557                  * When running as a Xen dom0 the number of processors Linux
 558                  * sees can be different from the real number of processors on
 559                  * the system, and we still need to execute _PDC or _OSC for
 560                  * all of them.
 561                  */
 562                 return xen_processor_present(acpi_id);
 563
 564         type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
 565         cpuid = acpi_get_cpuid(handle, type, acpi_id);
 566
 567         return !invalid_logical_cpuid(cpuid);
 568 }
 569
 570 /* vendor specific UUID indicating an Intel platform */
 571 static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
 572
 573 static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl,
 574                                              void *context, void **rv)
 575 {
 576         u32 capbuf[2] = {};
 577         struct acpi_osc_context osc_context = {
 578                 .uuid_str = sb_uuid_str,
 579                 .rev = 1,
 580                 .cap.length = 8,
 581                 .cap.pointer = capbuf,
 582         };
 583         acpi_status status;
 584
 585         if (!processor_physically_present(handle))
 586                 return AE_OK;
 587
 588         arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]);
 589
 590         status = acpi_run_osc(handle, &osc_context);
 591         if (ACPI_FAILURE(status))
 592                 return status;
 593
 594         kfree(osc_context.ret.pointer);
 595
 596         return AE_OK;
 597 }
 598
 599 static bool __init acpi_early_processor_osc(void)
 600 {
 601         acpi_status status;
 602
 603         acpi_proc_quirk_mwait_check();
 604
 605         status = acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 606                                      ACPI_UINT32_MAX, acpi_processor_osc, NULL,
 607                                      NULL, NULL);
 608         if (ACPI_FAILURE(status))
 609                 return false;
 610
 611         status = acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_osc,
 612                                   NULL, NULL);
 613         if (ACPI_FAILURE(status))
 614                 return false;
 615
 616         return true;
 617 }
 618
 619 void __init acpi_early_processor_control_setup(void)
 620 {
 621         if (acpi_early_processor_osc()) {
 622                 pr_debug("_OSC evaluated successfully for all CPUs\n");
 623         } else {
 624                 pr_debug("_OSC evaluation for CPUs failed, trying _PDC\n");
 625                 acpi_early_processor_set_pdc();
 626         }
 627 }
 628 #endif
 629
 630 /*
 631  * The following ACPI IDs are known to be suitable for representing as
 632  * processor devices.
 633  */
 634 static const struct acpi_device_id processor_device_ids[] = {
 635
 636         { ACPI_PROCESSOR_OBJECT_HID, },
 637         { ACPI_PROCESSOR_DEVICE_HID, },
 638
 639         { }
 640 };
 641
 642 static struct acpi_scan_handler processor_handler = {
 643         .ids = processor_device_ids,
 644         .attach = acpi_processor_add,
 645 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 646         .post_eject = acpi_processor_post_eject,
 647 #endif
 648         .hotplug = {
 649                 .enabled = true,
 650         },
 651 };
 652
 653 static int acpi_processor_container_attach(struct acpi_device *dev,
 654                                            const struct acpi_device_id *id)
 655 {
 656         return 1;
 657 }
 658
 659 static const struct acpi_device_id processor_container_ids[] = {
 660         { ACPI_PROCESSOR_CONTAINER_HID, },
 661         { }
 662 };
 663
 664 static struct acpi_scan_handler processor_container_handler = {
 665         .ids = processor_container_ids,
 666         .attach = acpi_processor_container_attach,
 667 };
 668
 669 /* The number of the unique processor IDs */
 670 static int nr_unique_ids __initdata;
 671
 672 /* The number of the duplicate processor IDs */
 673 static int nr_duplicate_ids;
 674
 675 /* Used to store the unique processor IDs */
 676 static int unique_processor_ids[] __initdata = {
 677         [0 ... NR_CPUS - 1] = -1,
 678 };
 679
 680 /* Used to store the duplicate processor IDs */
 681 static int duplicate_processor_ids[] = {
 682         [0 ... NR_CPUS - 1] = -1,
 683 };
 684
 685 static void __init processor_validated_ids_update(int proc_id)
 686 {
 687         int i;
 688
 689         if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
 690                 return;
 691
 692         /*
 693          * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
 694          * already in the IDs, do nothing.
 695          */
 696         for (i = 0; i < nr_duplicate_ids; i++) {
 697                 if (duplicate_processor_ids[i] == proc_id)
 698                         return;
 699         }
 700
 701         /*
 702          * Secondly, compare the proc_id with unique IDs, if the proc_id is in
 703          * the IDs, put it in the duplicate IDs.
 704          */
 705         for (i = 0; i < nr_unique_ids; i++) {
 706                 if (unique_processor_ids[i] == proc_id) {
 707                         duplicate_processor_ids[nr_duplicate_ids] = proc_id;
 708                         nr_duplicate_ids++;
 709                         return;
 710                 }
 711         }
 712
 713         /*
 714          * Lastly, the proc_id is a unique ID, put it in the unique IDs.
 715          */
 716         unique_processor_ids[nr_unique_ids] = proc_id;
 717         nr_unique_ids++;
 718 }
 719
 720 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
 721                                                   u32 lvl,
 722                                                   void *context,
 723                                                   void **rv)
 724 {
 725         acpi_status status;
 726         acpi_object_type acpi_type;
 727         unsigned long long uid;
 728         union acpi_object object = { 0 };
 729         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 730
 731         status = acpi_get_type(handle, &acpi_type);
 732         if (ACPI_FAILURE(status))
 733                 return status;
 734
 735         switch (acpi_type) {
 736         case ACPI_TYPE_PROCESSOR:
 737                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
 738                 if (ACPI_FAILURE(status))
 739                         goto err;
 740                 uid = object.processor.proc_id;
 741                 break;
 742
 743         case ACPI_TYPE_DEVICE:
 744                 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
 745                 if (ACPI_FAILURE(status))
 746                         goto err;
 747                 break;
 748         default:
 749                 goto err;
 750         }
 751
 752         processor_validated_ids_update(uid);
 753         return AE_OK;
 754
 755 err:
 756         /* Exit on error, but don't abort the namespace walk */
 757         acpi_handle_info(handle, "Invalid processor object\n");
 758         return AE_OK;
 759
 760 }
 761
 762 static void __init acpi_processor_check_duplicates(void)
 763 {
 764         /* check the correctness for all processors in ACPI namespace */
 765         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
 766                                                 ACPI_UINT32_MAX,
 767                                                 acpi_processor_ids_walk,
 768                                                 NULL, NULL, NULL);
 769         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
 770                                                 NULL, NULL);
 771 }
 772
 773 bool acpi_duplicate_processor_id(int proc_id)
 774 {
 775         int i;
 776
 777         /*
 778          * compare the proc_id with duplicate IDs, if the proc_id is already
 779          * in the duplicate IDs, return true, otherwise, return false.
 780          */
 781         for (i = 0; i < nr_duplicate_ids; i++) {
 782                 if (duplicate_processor_ids[i] == proc_id)
 783                         return true;
 784         }
 785         return false;
 786 }
 787
 788 void __init acpi_processor_init(void)
 789 {
 790         acpi_processor_check_duplicates();
 791         acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
 792         acpi_scan_add_handler(&processor_container_handler);
 793         acpi_pcc_cpufreq_init();
 794 }
 795
 796 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
 797 /**
 798  * acpi_processor_claim_cst_control - Request _CST control from the platform.
 799  */
 800 bool acpi_processor_claim_cst_control(void)
 801 {
 802         static bool cst_control_claimed;
 803         acpi_status status;
 804
 805         if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
 806                 return true;
 807
 808         status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
 809                                     acpi_gbl_FADT.cst_control, 8);
 810         if (ACPI_FAILURE(status)) {
 811                 pr_warn("ACPI: Failed to claim processor _CST control\n");
 812                 return false;
 813         }
 814
 815         cst_control_claimed = true;
 816         return true;
 817 }
 818 EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
 819
 820 /**
 821  * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
 822  * @handle: ACPI handle of the processor object containing the _CST.
 823  * @cpu: The numeric ID of the target CPU.
 824  * @info: Object write the C-states information into.
 825  *
 826  * Extract the C-state information for the given CPU from the output of the _CST
 827  * control method under the corresponding ACPI processor object (or processor
 828  * device object) and populate @info with it.
 829  *
 830  * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
 831  * acpi_processor_ffh_cstate_probe() to verify them and update the
 832  * cpu_cstate_entry data for @cpu.
 833  */
 834 int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
 835                                 struct acpi_processor_power *info)
 836 {
 837         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 838         union acpi_object *cst;
 839         acpi_status status;
 840         u64 count;
 841         int last_index = 0;
 842         int i, ret = 0;
 843
 844         status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
 845         if (ACPI_FAILURE(status)) {
 846                 acpi_handle_debug(handle, "No _CST\n");
 847                 return -ENODEV;
 848         }
 849
 850         cst = buffer.pointer;
 851
 852         /* There must be at least 2 elements. */
 853         if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
 854                 acpi_handle_warn(handle, "Invalid _CST output\n");
 855                 ret = -EFAULT;
 856                 goto end;
 857         }
 858
 859         count = cst->package.elements[0].integer.value;
 860
 861         /* Validate the number of C-states. */
 862         if (count < 1 || count != cst->package.count - 1) {
 863                 acpi_handle_warn(handle, "Inconsistent _CST data\n");
 864                 ret = -EFAULT;
 865                 goto end;
 866         }
 867
 868         for (i = 1; i <= count; i++) {
 869                 union acpi_object *element;
 870                 union acpi_object *obj;
 871                 struct acpi_power_register *reg;
 872                 struct acpi_processor_cx cx;
 873
 874                 /*
 875                  * If there is not enough space for all C-states, skip the
 876                  * excess ones and log a warning.
 877                  */
 878                 if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
 879                         acpi_handle_warn(handle,
 880                                          "No room for more idle states (limit: %d)\n",
 881                                          ACPI_PROCESSOR_MAX_POWER - 1);
 882                         break;
 883                 }
 884
 885                 memset(&cx, 0, sizeof(cx));
 886
 887                 element = &cst->package.elements[i];
 888                 if (element->type != ACPI_TYPE_PACKAGE) {
 889                         acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
 890                                          i, element->type);
 891                         continue;
 892                 }
 893
 894                 if (element->package.count != 4) {
 895                         acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
 896                                          i, element->package.count);
 897                         continue;
 898                 }
 899
 900                 obj = &element->package.elements[0];
 901
 902                 if (obj->type != ACPI_TYPE_BUFFER) {
 903                         acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
 904                                          i, obj->type);
 905                         continue;
 906                 }
 907
 908                 reg = (struct acpi_power_register *)obj->buffer.pointer;
 909
 910                 obj = &element->package.elements[1];
 911                 if (obj->type != ACPI_TYPE_INTEGER) {
 912                         acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
 913                                          i, obj->type);
 914                         continue;
 915                 }
 916
 917                 cx.type = obj->integer.value;
 918                 /*
 919                  * There are known cases in which the _CST output does not
 920                  * contain C1, so if the type of the first state found is not
 921                  * C1, leave an empty slot for C1 to be filled in later.
 922                  */
 923                 if (i == 1 && cx.type != ACPI_STATE_C1)
 924                         last_index = 1;
 925
 926                 cx.address = reg->address;
 927                 cx.index = last_index + 1;
 928
 929                 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
 930                         if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
 931                                 /*
 932                                  * In the majority of cases _CST describes C1 as
 933                                  * a FIXED_HARDWARE C-state, but if the command
 934                                  * line forbids using MWAIT, use CSTATE_HALT for
 935                                  * C1 regardless.
 936                                  */
 937                                 if (cx.type == ACPI_STATE_C1 &&
 938                                     boot_option_idle_override == IDLE_NOMWAIT) {
 939                                         cx.entry_method = ACPI_CSTATE_HALT;
 940                                         snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
 941                                 } else {
 942                                         cx.entry_method = ACPI_CSTATE_FFH;
 943                                 }
 944                         } else if (cx.type == ACPI_STATE_C1) {
 945                                 /*
 946                                  * In the special case of C1, FIXED_HARDWARE can
 947                                  * be handled by executing the HLT instruction.
 948                                  */
 949                                 cx.entry_method = ACPI_CSTATE_HALT;
 950                                 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
 951                         } else {
 952                                 acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
 953                                                  i);
 954                                 continue;
 955                         }
 956                 } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
 957                         cx.entry_method = ACPI_CSTATE_SYSTEMIO;
 958                         snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
 959                                  cx.address);
 960                 } else {
 961                         acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
 962                                          i, reg->space_id);
 963                         continue;
 964                 }
 965
 966                 if (cx.type == ACPI_STATE_C1)
 967                         cx.valid = 1;
 968
 969                 obj = &element->package.elements[2];
 970                 if (obj->type != ACPI_TYPE_INTEGER) {
 971                         acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
 972                                          i, obj->type);
 973                         continue;
 974                 }
 975
 976                 cx.latency = obj->integer.value;
 977
 978                 obj = &element->package.elements[3];
 979                 if (obj->type != ACPI_TYPE_INTEGER) {
 980                         acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
 981                                          i, obj->type);
 982                         continue;
 983                 }
 984
 985                 memcpy(&info->states[++last_index], &cx, sizeof(cx));
 986         }
 987
 988         acpi_handle_debug(handle, "Found %d idle states\n", last_index);
 989
 990         info->count = last_index;
 991
 992 end:
 993         kfree(buffer.pointer);
 994
 995         return ret;
 996 }
 997 EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
 998 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */