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