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