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