drivers/acpi/processor_driver.c

   1 /*
   2  * acpi_processor.c - ACPI Processor Driver ($Revision: 71 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *  Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
   7  *  Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
   8  *                      - Added processor hotplug support
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  *  TBD:
  28  *      1. Make # power states dynamic.
  29  *      2. Support duty_cycle values that span bit 4.
  30  *      3. Optimize by having scheduler determine business instead of
  31  *         having us try to calculate it here.
  32  *      4. Need C1 timing -- must modify kernel (IRQ handler) to get this.
  33  */
  34
  35 #include <linux/kernel.h>
  36 #include <linux/module.h>
  37 #include <linux/init.h>
  38 #include <linux/types.h>
  39 #include <linux/pci.h>
  40 #include <linux/pm.h>
  41 #include <linux/cpufreq.h>
  42 #include <linux/cpu.h>
  43 #include <linux/dmi.h>
  44 #include <linux/moduleparam.h>
  45 #include <linux/cpuidle.h>
  46 #include <linux/slab.h>
  47 #include <linux/acpi.h>
  48 #include <linux/memory_hotplug.h>
  49
  50 #include <asm/io.h>
  51 #include <asm/cpu.h>
  52 #include <asm/delay.h>
  53 #include <asm/uaccess.h>
  54 #include <asm/processor.h>
  55 #include <asm/smp.h>
  56 #include <asm/acpi.h>
  57
  58 #include <acpi/acpi_bus.h>
  59 #include <acpi/acpi_drivers.h>
  60 #include <acpi/processor.h>
  61
  62 #define PREFIX "ACPI: "
  63
  64 #define ACPI_PROCESSOR_CLASS            "processor"
  65 #define ACPI_PROCESSOR_DEVICE_NAME      "Processor"
  66 #define ACPI_PROCESSOR_FILE_INFO        "info"
  67 #define ACPI_PROCESSOR_FILE_THROTTLING  "throttling"
  68 #define ACPI_PROCESSOR_FILE_LIMIT       "limit"
  69 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
  70 #define ACPI_PROCESSOR_NOTIFY_POWER     0x81
  71 #define ACPI_PROCESSOR_NOTIFY_THROTTLING        0x82
  72 #define ACPI_PROCESSOR_DEVICE_HID       "ACPI0007"
  73
  74 #define ACPI_PROCESSOR_LIMIT_USER       0
  75 #define ACPI_PROCESSOR_LIMIT_THERMAL    1
  76
  77 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
  78 ACPI_MODULE_NAME("processor_driver");
  79
  80 MODULE_AUTHOR("Paul Diefenbaugh");
  81 MODULE_DESCRIPTION("ACPI Processor Driver");
  82 MODULE_LICENSE("GPL");
  83
  84 static int acpi_processor_add(struct acpi_device *device);
  85 static int acpi_processor_remove(struct acpi_device *device);
  86 static void acpi_processor_notify(struct acpi_device *device, u32 event);
  87 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr);
  88 static int acpi_processor_handle_eject(struct acpi_processor *pr);
  89 static int acpi_processor_start(struct acpi_processor *pr);
  90
  91 static const struct acpi_device_id processor_device_ids[] = {
  92         {ACPI_PROCESSOR_OBJECT_HID, 0},
  93         {ACPI_PROCESSOR_DEVICE_HID, 0},
  94         {"", 0},
  95 };
  96 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
  97
  98 static struct acpi_driver acpi_processor_driver = {
  99         .name = "processor",
 100         .class = ACPI_PROCESSOR_CLASS,
 101         .ids = processor_device_ids,
 102         .ops = {
 103                 .add = acpi_processor_add,
 104                 .remove = acpi_processor_remove,
 105                 .notify = acpi_processor_notify,
 106                 },
 107 };
 108
 109 #define INSTALL_NOTIFY_HANDLER          1
 110 #define UNINSTALL_NOTIFY_HANDLER        2
 111
 112 DEFINE_PER_CPU(struct acpi_processor *, processors);
 113 EXPORT_PER_CPU_SYMBOL(processors);
 114
 115 struct acpi_processor_errata errata __read_mostly;
 116
 117 /* --------------------------------------------------------------------------
 118                                 Errata Handling
 119    -------------------------------------------------------------------------- */
 120
 121 static int acpi_processor_errata_piix4(struct pci_dev *dev)
 122 {
 123         u8 value1 = 0;
 124         u8 value2 = 0;
 125
 126
 127         if (!dev)
 128                 return -EINVAL;
 129
 130         /*
 131          * Note that 'dev' references the PIIX4 ACPI Controller.
 132          */
 133
 134         switch (dev->revision) {
 135         case 0:
 136                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
 137                 break;
 138         case 1:
 139                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
 140                 break;
 141         case 2:
 142                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
 143                 break;
 144         case 3:
 145                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
 146                 break;
 147         default:
 148                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
 149                 break;
 150         }
 151
 152         switch (dev->revision) {
 153
 154         case 0:         /* PIIX4 A-step */
 155         case 1:         /* PIIX4 B-step */
 156                 /*
 157                  * See specification changes #13 ("Manual Throttle Duty Cycle")
 158                  * and #14 ("Enabling and Disabling Manual Throttle"), plus
 159                  * erratum #5 ("STPCLK# Deassertion Time") from the January
 160                  * 2002 PIIX4 specification update.  Applies to only older
 161                  * PIIX4 models.
 162                  */
 163                 errata.piix4.throttle = 1;
 164
 165         case 2:         /* PIIX4E */
 166         case 3:         /* PIIX4M */
 167                 /*
 168                  * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
 169                  * Livelock") from the January 2002 PIIX4 specification update.
 170                  * Applies to all PIIX4 models.
 171                  */
 172
 173                 /*
 174                  * BM-IDE
 175                  * ------
 176                  * Find the PIIX4 IDE Controller and get the Bus Master IDE
 177                  * Status register address.  We'll use this later to read
 178                  * each IDE controller's DMA status to make sure we catch all
 179                  * DMA activity.
 180                  */
 181                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 182                                      PCI_DEVICE_ID_INTEL_82371AB,
 183                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 184                 if (dev) {
 185                         errata.piix4.bmisx = pci_resource_start(dev, 4);
 186                         pci_dev_put(dev);
 187                 }
 188
 189                 /*
 190                  * Type-F DMA
 191                  * ----------
 192                  * Find the PIIX4 ISA Controller and read the Motherboard
 193                  * DMA controller's status to see if Type-F (Fast) DMA mode
 194                  * is enabled (bit 7) on either channel.  Note that we'll
 195                  * disable C3 support if this is enabled, as some legacy
 196                  * devices won't operate well if fast DMA is disabled.
 197                  */
 198                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 199                                      PCI_DEVICE_ID_INTEL_82371AB_0,
 200                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 201                 if (dev) {
 202                         pci_read_config_byte(dev, 0x76, &value1);
 203                         pci_read_config_byte(dev, 0x77, &value2);
 204                         if ((value1 & 0x80) || (value2 & 0x80))
 205                                 errata.piix4.fdma = 1;
 206                         pci_dev_put(dev);
 207                 }
 208
 209                 break;
 210         }
 211
 212         if (errata.piix4.bmisx)
 213                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 214                                   "Bus master activity detection (BM-IDE) erratum enabled\n"));
 215         if (errata.piix4.fdma)
 216                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 217                                   "Type-F DMA livelock erratum (C3 disabled)\n"));
 218
 219         return 0;
 220 }
 221
 222 static int acpi_processor_errata(struct acpi_processor *pr)
 223 {
 224         int result = 0;
 225         struct pci_dev *dev = NULL;
 226
 227
 228         if (!pr)
 229                 return -EINVAL;
 230
 231         /*
 232          * PIIX4
 233          */
 234         dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 235                              PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
 236                              PCI_ANY_ID, NULL);
 237         if (dev) {
 238                 result = acpi_processor_errata_piix4(dev);
 239                 pci_dev_put(dev);
 240         }
 241
 242         return result;
 243 }
 244
 245 /* --------------------------------------------------------------------------
 246                                  Driver Interface
 247    -------------------------------------------------------------------------- */
 248
 249 static int acpi_processor_get_info(struct acpi_device *device)
 250 {
 251         acpi_status status = 0;
 252         union acpi_object object = { 0 };
 253         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 254         struct acpi_processor *pr;
 255         int cpu_index, device_declaration = 0;
 256         static int cpu0_initialized;
 257
 258         pr = acpi_driver_data(device);
 259         if (!pr)
 260                 return -EINVAL;
 261
 262         if (num_online_cpus() > 1)
 263                 errata.smp = TRUE;
 264
 265         acpi_processor_errata(pr);
 266
 267         /*
 268          * Check to see if we have bus mastering arbitration control.  This
 269          * is required for proper C3 usage (to maintain cache coherency).
 270          */
 271         if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
 272                 pr->flags.bm_control = 1;
 273                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 274                                   "Bus mastering arbitration control present\n"));
 275         } else
 276                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 277                                   "No bus mastering arbitration control\n"));
 278
 279         if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
 280                 /* Declared with "Processor" statement; match ProcessorID */
 281                 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
 282                 if (ACPI_FAILURE(status)) {
 283                         dev_err(&device->dev,
 284                                 "Failed to evaluate processor object (0x%x)\n",
 285                                 status);
 286                         return -ENODEV;
 287                 }
 288
 289                 /*
 290                  * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
 291                  *      >>> 'acpi_get_processor_id(acpi_id, &id)' in
 292                  *      arch/xxx/acpi.c
 293                  */
 294                 pr->acpi_id = object.processor.proc_id;
 295         } else {
 296                 /*
 297                  * Declared with "Device" statement; match _UID.
 298                  * Note that we don't handle string _UIDs yet.
 299                  */
 300                 unsigned long long value;
 301                 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
 302                                                 NULL, &value);
 303                 if (ACPI_FAILURE(status)) {
 304                         dev_err(&device->dev,
 305                                 "Failed to evaluate processor _UID (0x%x)\n",
 306                                 status);
 307                         return -ENODEV;
 308                 }
 309                 device_declaration = 1;
 310                 pr->acpi_id = value;
 311         }
 312         cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id);
 313
 314         /* Handle UP system running SMP kernel, with no LAPIC in MADT */
 315         if (!cpu0_initialized && (cpu_index == -1) &&
 316             (num_online_cpus() == 1)) {
 317                 cpu_index = 0;
 318         }
 319
 320         cpu0_initialized = 1;
 321
 322         pr->id = cpu_index;
 323
 324         /*
 325          *  Extra Processor objects may be enumerated on MP systems with
 326          *  less than the max # of CPUs. They should be ignored _iff
 327          *  they are physically not present.
 328          */
 329         if (pr->id == -1) {
 330                 if (ACPI_FAILURE(acpi_processor_hotadd_init(pr)))
 331                         return -ENODEV;
 332         }
 333         /*
 334          * On some boxes several processors use the same processor bus id.
 335          * But they are located in different scope. For example:
 336          * \_SB.SCK0.CPU0
 337          * \_SB.SCK1.CPU0
 338          * Rename the processor device bus id. And the new bus id will be
 339          * generated as the following format:
 340          * CPU+CPU ID.
 341          */
 342         sprintf(acpi_device_bid(device), "CPU%X", pr->id);
 343         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
 344                           pr->acpi_id));
 345
 346         if (!object.processor.pblk_address)
 347                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
 348         else if (object.processor.pblk_length != 6)
 349                 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
 350                             object.processor.pblk_length);
 351         else {
 352                 pr->throttling.address = object.processor.pblk_address;
 353                 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
 354                 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
 355
 356                 pr->pblk = object.processor.pblk_address;
 357
 358                 /*
 359                  * We don't care about error returns - we just try to mark
 360                  * these reserved so that nobody else is confused into thinking
 361                  * that this region might be unused..
 362                  *
 363                  * (In particular, allocating the IO range for Cardbus)
 364                  */
 365                 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
 366         }
 367
 368         /*
 369          * If ACPI describes a slot number for this CPU, we can use it
 370          * ensure we get the right value in the "physical id" field
 371          * of /proc/cpuinfo
 372          */
 373         status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer);
 374         if (ACPI_SUCCESS(status))
 375                 arch_fix_phys_package_id(pr->id, object.integer.value);
 376
 377         return 0;
 378 }
 379
 380 static DEFINE_PER_CPU(void *, processor_device_array);
 381
 382 static void acpi_processor_notify(struct acpi_device *device, u32 event)
 383 {
 384         struct acpi_processor *pr = acpi_driver_data(device);
 385         int saved;
 386
 387         if (!pr)
 388                 return;
 389
 390         switch (event) {
 391         case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
 392                 saved = pr->performance_platform_limit;
 393                 acpi_processor_ppc_has_changed(pr, 1);
 394                 if (saved == pr->performance_platform_limit)
 395                         break;
 396                 acpi_bus_generate_proc_event(device, event,
 397                                         pr->performance_platform_limit);
 398                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 399                                                   dev_name(&device->dev), event,
 400                                                   pr->performance_platform_limit);
 401                 break;
 402         case ACPI_PROCESSOR_NOTIFY_POWER:
 403                 acpi_processor_cst_has_changed(pr);
 404                 acpi_bus_generate_proc_event(device, event, 0);
 405                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 406                                                   dev_name(&device->dev), event, 0);
 407                 break;
 408         case ACPI_PROCESSOR_NOTIFY_THROTTLING:
 409                 acpi_processor_tstate_has_changed(pr);
 410                 acpi_bus_generate_proc_event(device, event, 0);
 411                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 412                                                   dev_name(&device->dev), event, 0);
 413                 break;
 414         default:
 415                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 416                                   "Unsupported event [0x%x]\n", event));
 417                 break;
 418         }
 419
 420         return;
 421 }
 422
 423 static int acpi_cpu_soft_notify(struct notifier_block *nfb,
 424                 unsigned long action, void *hcpu)
 425 {
 426         unsigned int cpu = (unsigned long)hcpu;
 427         struct acpi_processor *pr = per_cpu(processors, cpu);
 428
 429         if (action == CPU_ONLINE && pr) {
 430                 /* CPU got physically hotplugged and onlined the first time:
 431                  * Initialize missing things
 432                  */
 433                 if (pr->flags.need_hotplug_init) {
 434                         pr_info("Will online and init hotplugged CPU: %d\n",
 435                                 pr->id);
 436                         WARN(acpi_processor_start(pr), "Failed to start CPU:"
 437                                 " %d\n", pr->id);
 438                         pr->flags.need_hotplug_init = 0;
 439                 /* Normal CPU soft online event */
 440                 } else {
 441                         acpi_processor_ppc_has_changed(pr, 0);
 442                         acpi_processor_hotplug(pr);
 443                         acpi_processor_reevaluate_tstate(pr, action);
 444                         acpi_processor_tstate_has_changed(pr);
 445                 }
 446         }
 447         if (action == CPU_DEAD && pr) {
 448                 /* invalidate the flag.throttling after one CPU is offline */
 449                 acpi_processor_reevaluate_tstate(pr, action);
 450         }
 451         return NOTIFY_OK;
 452 }
 453
 454 static struct notifier_block acpi_cpu_notifier =
 455 {
 456             .notifier_call = acpi_cpu_soft_notify,
 457 };
 458
 459 /*
 460  * acpi_processor_start() is called by the cpu_hotplug_notifier func:
 461  * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the
 462  * root cause seem to be that acpi_processor_uninstall_hotplug_notify()
 463  * is in the module_exit (__exit) func. Allowing acpi_processor_start()
 464  * to not be in __cpuinit section, but being called from __cpuinit funcs
 465  * via __ref looks like the right thing to do here.
 466  */
 467 static __ref int acpi_processor_start(struct acpi_processor *pr)
 468 {
 469         struct acpi_device *device = per_cpu(processor_device_array, pr->id);
 470         int result = 0;
 471
 472 #ifdef CONFIG_CPU_FREQ
 473         acpi_processor_ppc_has_changed(pr, 0);
 474         acpi_processor_load_module(pr);
 475 #endif
 476         acpi_processor_get_throttling_info(pr);
 477         acpi_processor_get_limit_info(pr);
 478
 479         if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
 480                 acpi_processor_power_init(pr);
 481
 482         pr->cdev = thermal_cooling_device_register("Processor", device,
 483                                                    &processor_cooling_ops);
 484         if (IS_ERR(pr->cdev)) {
 485                 result = PTR_ERR(pr->cdev);
 486                 goto err_power_exit;
 487         }
 488
 489         dev_dbg(&device->dev, "registered as cooling_device%d\n",
 490                 pr->cdev->id);
 491
 492         result = sysfs_create_link(&device->dev.kobj,
 493                                    &pr->cdev->device.kobj,
 494                                    "thermal_cooling");
 495         if (result) {
 496                 dev_err(&device->dev,
 497                         "Failed to create sysfs link 'thermal_cooling'\n");
 498                 goto err_thermal_unregister;
 499         }
 500         result = sysfs_create_link(&pr->cdev->device.kobj,
 501                                    &device->dev.kobj,
 502                                    "device");
 503         if (result) {
 504                 dev_err(&pr->cdev->device,
 505                         "Failed to create sysfs link 'device'\n");
 506                 goto err_remove_sysfs_thermal;
 507         }
 508
 509         return 0;
 510
 511 err_remove_sysfs_thermal:
 512         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 513 err_thermal_unregister:
 514         thermal_cooling_device_unregister(pr->cdev);
 515 err_power_exit:
 516         acpi_processor_power_exit(pr);
 517
 518         return result;
 519 }
 520
 521 /*
 522  * Do not put anything in here which needs the core to be online.
 523  * For example MSR access or setting up things which check for cpuinfo_x86
 524  * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
 525  * Such things have to be put in and set up above in acpi_processor_start()
 526  */
 527 static int __cpuinit acpi_processor_add(struct acpi_device *device)
 528 {
 529         struct acpi_processor *pr = NULL;
 530         int result = 0;
 531         struct device *dev;
 532
 533         pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
 534         if (!pr)
 535                 return -ENOMEM;
 536
 537         if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
 538                 result = -ENOMEM;
 539                 goto err_free_pr;
 540         }
 541
 542         pr->handle = device->handle;
 543         strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 544         strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
 545         device->driver_data = pr;
 546
 547         result = acpi_processor_get_info(device);
 548         if (result) {
 549                 /* Processor is physically not present */
 550                 return 0;
 551         }
 552
 553 #ifdef CONFIG_SMP
 554         if (pr->id >= setup_max_cpus && pr->id != 0)
 555                 return 0;
 556 #endif
 557
 558         BUG_ON(pr->id >= nr_cpu_ids);
 559
 560         /*
 561          * Buggy BIOS check
 562          * ACPI id of processors can be reported wrongly by the BIOS.
 563          * Don't trust it blindly
 564          */
 565         if (per_cpu(processor_device_array, pr->id) != NULL &&
 566             per_cpu(processor_device_array, pr->id) != device) {
 567                 dev_warn(&device->dev,
 568                         "BIOS reported wrong ACPI id %d for the processor\n",
 569                         pr->id);
 570                 result = -ENODEV;
 571                 goto err_free_cpumask;
 572         }
 573         per_cpu(processor_device_array, pr->id) = device;
 574
 575         per_cpu(processors, pr->id) = pr;
 576
 577         dev = get_cpu_device(pr->id);
 578         if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
 579                 result = -EFAULT;
 580                 goto err_clear_processor;
 581         }
 582
 583         /*
 584          * Do not start hotplugged CPUs now, but when they
 585          * are onlined the first time
 586          */
 587         if (pr->flags.need_hotplug_init)
 588                 return 0;
 589
 590         result = acpi_processor_start(pr);
 591         if (result)
 592                 goto err_remove_sysfs;
 593
 594         return 0;
 595
 596 err_remove_sysfs:
 597         sysfs_remove_link(&device->dev.kobj, "sysdev");
 598 err_clear_processor:
 599         /*
 600          * processor_device_array is not cleared to allow checks for buggy BIOS
 601          */
 602         per_cpu(processors, pr->id) = NULL;
 603 err_free_cpumask:
 604         free_cpumask_var(pr->throttling.shared_cpu_map);
 605 err_free_pr:
 606         kfree(pr);
 607         return result;
 608 }
 609
 610 static int acpi_processor_remove(struct acpi_device *device)
 611 {
 612         struct acpi_processor *pr = NULL;
 613
 614
 615         if (!device || !acpi_driver_data(device))
 616                 return -EINVAL;
 617
 618         pr = acpi_driver_data(device);
 619
 620         if (pr->id >= nr_cpu_ids)
 621                 goto free;
 622
 623         if (device->removal_type == ACPI_BUS_REMOVAL_EJECT) {
 624                 if (acpi_processor_handle_eject(pr))
 625                         return -EINVAL;
 626         }
 627
 628         acpi_processor_power_exit(pr);
 629
 630         sysfs_remove_link(&device->dev.kobj, "sysdev");
 631
 632         if (pr->cdev) {
 633                 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 634                 sysfs_remove_link(&pr->cdev->device.kobj, "device");
 635                 thermal_cooling_device_unregister(pr->cdev);
 636                 pr->cdev = NULL;
 637         }
 638
 639         per_cpu(processors, pr->id) = NULL;
 640         per_cpu(processor_device_array, pr->id) = NULL;
 641         try_offline_node(cpu_to_node(pr->id));
 642
 643 free:
 644         free_cpumask_var(pr->throttling.shared_cpu_map);
 645         kfree(pr);
 646
 647         return 0;
 648 }
 649
 650 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 651 /****************************************************************************
 652  *      Acpi processor hotplug support                                      *
 653  ****************************************************************************/
 654
 655 static int is_processor_present(acpi_handle handle)
 656 {
 657         acpi_status status;
 658         unsigned long long sta = 0;
 659
 660
 661         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 662
 663         if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
 664                 return 1;
 665
 666         /*
 667          * _STA is mandatory for a processor that supports hot plug
 668          */
 669         if (status == AE_NOT_FOUND)
 670                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 671                                 "Processor does not support hot plug\n"));
 672         else
 673                 ACPI_EXCEPTION((AE_INFO, status,
 674                                 "Processor Device is not present"));
 675         return 0;
 676 }
 677
 678 static void acpi_processor_hotplug_notify(acpi_handle handle,
 679                                           u32 event, void *data)
 680 {
 681         struct acpi_device *device = NULL;
 682         struct acpi_eject_event *ej_event = NULL;
 683         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
 684         acpi_status status;
 685         int result;
 686
 687         acpi_scan_lock_acquire();
 688
 689         switch (event) {
 690         case ACPI_NOTIFY_BUS_CHECK:
 691         case ACPI_NOTIFY_DEVICE_CHECK:
 692                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 693                 "Processor driver received %s event\n",
 694                        (event == ACPI_NOTIFY_BUS_CHECK) ?
 695                        "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK"));
 696
 697                 if (!is_processor_present(handle))
 698                         break;
 699
 700                 if (!acpi_bus_get_device(handle, &device))
 701                         break;
 702
 703                 result = acpi_bus_scan(handle);
 704                 if (result) {
 705                         acpi_handle_err(handle, "Unable to add the device\n");
 706                         break;
 707                 }
 708                 result = acpi_bus_get_device(handle, &device);
 709                 if (result) {
 710                         acpi_handle_err(handle, "Missing device object\n");
 711                         break;
 712                 }
 713                 ost_code = ACPI_OST_SC_SUCCESS;
 714                 break;
 715
 716         case ACPI_NOTIFY_EJECT_REQUEST:
 717                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 718                                   "received ACPI_NOTIFY_EJECT_REQUEST\n"));
 719
 720                 if (acpi_bus_get_device(handle, &device)) {
 721                         acpi_handle_err(handle,
 722                                 "Device don't exist, dropping EJECT\n");
 723                         break;
 724                 }
 725                 if (!acpi_driver_data(device)) {
 726                         acpi_handle_err(handle,
 727                                 "Driver data is NULL, dropping EJECT\n");
 728                         break;
 729                 }
 730
 731                 ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);
 732                 if (!ej_event) {
 733                         acpi_handle_err(handle, "No memory, dropping EJECT\n");
 734                         break;
 735                 }
 736
 737                 get_device(&device->dev);
 738                 ej_event->device = device;
 739                 ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;
 740                 /* The eject is carried out asynchronously. */
 741                 status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device,
 742                                                  ej_event);
 743                 if (ACPI_FAILURE(status)) {
 744                         put_device(&device->dev);
 745                         kfree(ej_event);
 746                         break;
 747                 }
 748                 goto out;
 749
 750         default:
 751                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 752                                   "Unsupported event [0x%x]\n", event));
 753
 754                 /* non-hotplug event; possibly handled by other handler */
 755                 goto out;
 756         }
 757
 758         /* Inform firmware that the hotplug operation has completed */
 759         (void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL);
 760
 761  out:
 762         acpi_scan_lock_release();
 763 }
 764
 765 static acpi_status is_processor_device(acpi_handle handle)
 766 {
 767         struct acpi_device_info *info;
 768         char *hid;
 769         acpi_status status;
 770
 771         status = acpi_get_object_info(handle, &info);
 772         if (ACPI_FAILURE(status))
 773                 return status;
 774
 775         if (info->type == ACPI_TYPE_PROCESSOR) {
 776                 kfree(info);
 777                 return AE_OK;   /* found a processor object */
 778         }
 779
 780         if (!(info->valid & ACPI_VALID_HID)) {
 781                 kfree(info);
 782                 return AE_ERROR;
 783         }
 784
 785         hid = info->hardware_id.string;
 786         if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) {
 787                 kfree(info);
 788                 return AE_ERROR;
 789         }
 790
 791         kfree(info);
 792         return AE_OK;   /* found a processor device object */
 793 }
 794
 795 static acpi_status
 796 processor_walk_namespace_cb(acpi_handle handle,
 797                             u32 lvl, void *context, void **rv)
 798 {
 799         acpi_status status;
 800         int *action = context;
 801
 802         status = is_processor_device(handle);
 803         if (ACPI_FAILURE(status))
 804                 return AE_OK;   /* not a processor; continue to walk */
 805
 806         switch (*action) {
 807         case INSTALL_NOTIFY_HANDLER:
 808                 acpi_install_notify_handler(handle,
 809                                             ACPI_SYSTEM_NOTIFY,
 810                                             acpi_processor_hotplug_notify,
 811                                             NULL);
 812                 break;
 813         case UNINSTALL_NOTIFY_HANDLER:
 814                 acpi_remove_notify_handler(handle,
 815                                            ACPI_SYSTEM_NOTIFY,
 816                                            acpi_processor_hotplug_notify);
 817                 break;
 818         default:
 819                 break;
 820         }
 821
 822         /* found a processor; skip walking underneath */
 823         return AE_CTRL_DEPTH;
 824 }
 825
 826 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 827 {
 828         acpi_handle handle = pr->handle;
 829
 830         if (!is_processor_present(handle)) {
 831                 return AE_ERROR;
 832         }
 833
 834         if (acpi_map_lsapic(handle, &pr->id))
 835                 return AE_ERROR;
 836
 837         if (arch_register_cpu(pr->id)) {
 838                 acpi_unmap_lsapic(pr->id);
 839                 return AE_ERROR;
 840         }
 841
 842         /* CPU got hot-plugged, but cpu_data is not initialized yet
 843          * Set flag to delay cpu_idle/throttling initialization
 844          * in:
 845          * acpi_processor_add()
 846          *   acpi_processor_get_info()
 847          * and do it when the CPU gets online the first time
 848          * TBD: Cleanup above functions and try to do this more elegant.
 849          */
 850         pr_info("CPU %d got hotplugged\n", pr->id);
 851         pr->flags.need_hotplug_init = 1;
 852
 853         return AE_OK;
 854 }
 855
 856 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 857 {
 858         if (cpu_online(pr->id))
 859                 cpu_down(pr->id);
 860
 861         get_online_cpus();
 862         /*
 863          * The cpu might become online again at this point. So we check whether
 864          * the cpu has been onlined or not. If the cpu became online, it means
 865          * that someone wants to use the cpu. So acpi_processor_handle_eject()
 866          * returns -EAGAIN.
 867          */
 868         if (unlikely(cpu_online(pr->id))) {
 869                 put_online_cpus();
 870                 pr_warn("Failed to remove CPU %d, because other task "
 871                         "brought the CPU back online\n", pr->id);
 872                 return -EAGAIN;
 873         }
 874         arch_unregister_cpu(pr->id);
 875         acpi_unmap_lsapic(pr->id);
 876         put_online_cpus();
 877         return (0);
 878 }
 879 #else
 880 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 881 {
 882         return AE_ERROR;
 883 }
 884 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 885 {
 886         return (-EINVAL);
 887 }
 888 #endif
 889
 890 static
 891 void acpi_processor_install_hotplug_notify(void)
 892 {
 893 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 894         int action = INSTALL_NOTIFY_HANDLER;
 895         acpi_walk_namespace(ACPI_TYPE_ANY,
 896                             ACPI_ROOT_OBJECT,
 897                             ACPI_UINT32_MAX,
 898                             processor_walk_namespace_cb, NULL, &action, NULL);
 899 #endif
 900         register_hotcpu_notifier(&acpi_cpu_notifier);
 901 }
 902
 903 static
 904 void acpi_processor_uninstall_hotplug_notify(void)
 905 {
 906 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 907         int action = UNINSTALL_NOTIFY_HANDLER;
 908         acpi_walk_namespace(ACPI_TYPE_ANY,
 909                             ACPI_ROOT_OBJECT,
 910                             ACPI_UINT32_MAX,
 911                             processor_walk_namespace_cb, NULL, &action, NULL);
 912 #endif
 913         unregister_hotcpu_notifier(&acpi_cpu_notifier);
 914 }
 915
 916 /*
 917  * We keep the driver loaded even when ACPI is not running.
 918  * This is needed for the powernow-k8 driver, that works even without
 919  * ACPI, but needs symbols from this driver
 920  */
 921
 922 static int __init acpi_processor_init(void)
 923 {
 924         int result = 0;
 925
 926         if (acpi_disabled)
 927                 return 0;
 928
 929         result = acpi_bus_register_driver(&acpi_processor_driver);
 930         if (result < 0)
 931                 return result;
 932
 933         acpi_processor_syscore_init();
 934
 935         acpi_processor_install_hotplug_notify();
 936
 937         acpi_thermal_cpufreq_init();
 938
 939         acpi_processor_ppc_init();
 940
 941         acpi_processor_throttling_init();
 942
 943         return 0;
 944 }
 945
 946 static void __exit acpi_processor_exit(void)
 947 {
 948         if (acpi_disabled)
 949                 return;
 950
 951         acpi_processor_ppc_exit();
 952
 953         acpi_thermal_cpufreq_exit();
 954
 955         acpi_processor_uninstall_hotplug_notify();
 956
 957         acpi_processor_syscore_exit();
 958
 959         acpi_bus_unregister_driver(&acpi_processor_driver);
 960
 961         return;
 962 }
 963
 964 module_init(acpi_processor_init);
 965 module_exit(acpi_processor_exit);
 966
 967 MODULE_ALIAS("processor");