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
  48 #include <asm/io.h>
  49 #include <asm/cpu.h>
  50 #include <asm/delay.h>
  51 #include <asm/uaccess.h>
  52 #include <asm/processor.h>
  53 #include <asm/smp.h>
  54 #include <asm/acpi.h>
  55
  56 #include <acpi/acpi_bus.h>
  57 #include <acpi/acpi_drivers.h>
  58 #include <acpi/processor.h>
  59
  60 #define PREFIX "ACPI: "
  61
  62 #define ACPI_PROCESSOR_CLASS            "processor"
  63 #define ACPI_PROCESSOR_DEVICE_NAME      "Processor"
  64 #define ACPI_PROCESSOR_FILE_INFO        "info"
  65 #define ACPI_PROCESSOR_FILE_THROTTLING  "throttling"
  66 #define ACPI_PROCESSOR_FILE_LIMIT       "limit"
  67 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
  68 #define ACPI_PROCESSOR_NOTIFY_POWER     0x81
  69 #define ACPI_PROCESSOR_NOTIFY_THROTTLING        0x82
  70
  71 #define ACPI_PROCESSOR_LIMIT_USER       0
  72 #define ACPI_PROCESSOR_LIMIT_THERMAL    1
  73
  74 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
  75 ACPI_MODULE_NAME("processor_driver");
  76
  77 MODULE_AUTHOR("Paul Diefenbaugh");
  78 MODULE_DESCRIPTION("ACPI Processor Driver");
  79 MODULE_LICENSE("GPL");
  80
  81 static int acpi_processor_add(struct acpi_device *device);
  82 static int acpi_processor_remove(struct acpi_device *device, int type);
  83 static void acpi_processor_notify(struct acpi_device *device, u32 event);
  84 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr);
  85 static int acpi_processor_handle_eject(struct acpi_processor *pr);
  86 static int acpi_processor_start(struct acpi_processor *pr);
  87
  88 static const struct acpi_device_id processor_device_ids[] = {
  89         {ACPI_PROCESSOR_OBJECT_HID, 0},
  90         {"ACPI0007", 0},
  91         {"", 0},
  92 };
  93 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
  94
  95 static struct acpi_driver acpi_processor_driver = {
  96         .name = "processor",
  97         .class = ACPI_PROCESSOR_CLASS,
  98         .ids = processor_device_ids,
  99         .ops = {
 100                 .add = acpi_processor_add,
 101                 .remove = acpi_processor_remove,
 102                 .suspend = acpi_processor_suspend,
 103                 .resume = acpi_processor_resume,
 104                 .notify = acpi_processor_notify,
 105                 },
 106 };
 107
 108 #define INSTALL_NOTIFY_HANDLER          1
 109 #define UNINSTALL_NOTIFY_HANDLER        2
 110
 111 DEFINE_PER_CPU(struct acpi_processor *, processors);
 112 EXPORT_PER_CPU_SYMBOL(processors);
 113
 114 struct acpi_processor_errata errata __read_mostly;
 115
 116 /* --------------------------------------------------------------------------
 117                                 Errata Handling
 118    -------------------------------------------------------------------------- */
 119
 120 static int acpi_processor_errata_piix4(struct pci_dev *dev)
 121 {
 122         u8 value1 = 0;
 123         u8 value2 = 0;
 124
 125
 126         if (!dev)
 127                 return -EINVAL;
 128
 129         /*
 130          * Note that 'dev' references the PIIX4 ACPI Controller.
 131          */
 132
 133         switch (dev->revision) {
 134         case 0:
 135                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
 136                 break;
 137         case 1:
 138                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
 139                 break;
 140         case 2:
 141                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
 142                 break;
 143         case 3:
 144                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
 145                 break;
 146         default:
 147                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
 148                 break;
 149         }
 150
 151         switch (dev->revision) {
 152
 153         case 0:         /* PIIX4 A-step */
 154         case 1:         /* PIIX4 B-step */
 155                 /*
 156                  * See specification changes #13 ("Manual Throttle Duty Cycle")
 157                  * and #14 ("Enabling and Disabling Manual Throttle"), plus
 158                  * erratum #5 ("STPCLK# Deassertion Time") from the January
 159                  * 2002 PIIX4 specification update.  Applies to only older
 160                  * PIIX4 models.
 161                  */
 162                 errata.piix4.throttle = 1;
 163
 164         case 2:         /* PIIX4E */
 165         case 3:         /* PIIX4M */
 166                 /*
 167                  * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
 168                  * Livelock") from the January 2002 PIIX4 specification update.
 169                  * Applies to all PIIX4 models.
 170                  */
 171
 172                 /*
 173                  * BM-IDE
 174                  * ------
 175                  * Find the PIIX4 IDE Controller and get the Bus Master IDE
 176                  * Status register address.  We'll use this later to read
 177                  * each IDE controller's DMA status to make sure we catch all
 178                  * DMA activity.
 179                  */
 180                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 181                                      PCI_DEVICE_ID_INTEL_82371AB,
 182                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 183                 if (dev) {
 184                         errata.piix4.bmisx = pci_resource_start(dev, 4);
 185                         pci_dev_put(dev);
 186                 }
 187
 188                 /*
 189                  * Type-F DMA
 190                  * ----------
 191                  * Find the PIIX4 ISA Controller and read the Motherboard
 192                  * DMA controller's status to see if Type-F (Fast) DMA mode
 193                  * is enabled (bit 7) on either channel.  Note that we'll
 194                  * disable C3 support if this is enabled, as some legacy
 195                  * devices won't operate well if fast DMA is disabled.
 196                  */
 197                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 198                                      PCI_DEVICE_ID_INTEL_82371AB_0,
 199                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
 200                 if (dev) {
 201                         pci_read_config_byte(dev, 0x76, &value1);
 202                         pci_read_config_byte(dev, 0x77, &value2);
 203                         if ((value1 & 0x80) || (value2 & 0x80))
 204                                 errata.piix4.fdma = 1;
 205                         pci_dev_put(dev);
 206                 }
 207
 208                 break;
 209         }
 210
 211         if (errata.piix4.bmisx)
 212                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 213                                   "Bus master activity detection (BM-IDE) erratum enabled\n"));
 214         if (errata.piix4.fdma)
 215                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 216                                   "Type-F DMA livelock erratum (C3 disabled)\n"));
 217
 218         return 0;
 219 }
 220
 221 static int acpi_processor_errata(struct acpi_processor *pr)
 222 {
 223         int result = 0;
 224         struct pci_dev *dev = NULL;
 225
 226
 227         if (!pr)
 228                 return -EINVAL;
 229
 230         /*
 231          * PIIX4
 232          */
 233         dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 234                              PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
 235                              PCI_ANY_ID, NULL);
 236         if (dev) {
 237                 result = acpi_processor_errata_piix4(dev);
 238                 pci_dev_put(dev);
 239         }
 240
 241         return result;
 242 }
 243
 244 /* --------------------------------------------------------------------------
 245                                  Driver Interface
 246    -------------------------------------------------------------------------- */
 247
 248 static int acpi_processor_get_info(struct acpi_device *device)
 249 {
 250         acpi_status status = 0;
 251         union acpi_object object = { 0 };
 252         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 253         struct acpi_processor *pr;
 254         int cpu_index, device_declaration = 0;
 255         static int cpu0_initialized;
 256
 257         pr = acpi_driver_data(device);
 258         if (!pr)
 259                 return -EINVAL;
 260
 261         if (num_online_cpus() > 1)
 262                 errata.smp = TRUE;
 263
 264         acpi_processor_errata(pr);
 265
 266         /*
 267          * Check to see if we have bus mastering arbitration control.  This
 268          * is required for proper C3 usage (to maintain cache coherency).
 269          */
 270         if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
 271                 pr->flags.bm_control = 1;
 272                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 273                                   "Bus mastering arbitration control present\n"));
 274         } else
 275                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 276                                   "No bus mastering arbitration control\n"));
 277
 278         if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
 279                 /* Declared with "Processor" statement; match ProcessorID */
 280                 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
 281                 if (ACPI_FAILURE(status)) {
 282                         printk(KERN_ERR PREFIX "Evaluating processor object\n");
 283                         return -ENODEV;
 284                 }
 285
 286                 /*
 287                  * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
 288                  *      >>> 'acpi_get_processor_id(acpi_id, &id)' in
 289                  *      arch/xxx/acpi.c
 290                  */
 291                 pr->acpi_id = object.processor.proc_id;
 292         } else {
 293                 /*
 294                  * Declared with "Device" statement; match _UID.
 295                  * Note that we don't handle string _UIDs yet.
 296                  */
 297                 unsigned long long value;
 298                 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
 299                                                 NULL, &value);
 300                 if (ACPI_FAILURE(status)) {
 301                         printk(KERN_ERR PREFIX
 302                             "Evaluating processor _UID [%#x]\n", status);
 303                         return -ENODEV;
 304                 }
 305                 device_declaration = 1;
 306                 pr->acpi_id = value;
 307         }
 308         cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id);
 309
 310         /* Handle UP system running SMP kernel, with no LAPIC in MADT */
 311         if (!cpu0_initialized && (cpu_index == -1) &&
 312             (num_online_cpus() == 1)) {
 313                 cpu_index = 0;
 314         }
 315
 316         cpu0_initialized = 1;
 317
 318         pr->id = cpu_index;
 319
 320         /*
 321          *  Extra Processor objects may be enumerated on MP systems with
 322          *  less than the max # of CPUs. They should be ignored _iff
 323          *  they are physically not present.
 324          */
 325         if (pr->id == -1) {
 326                 if (ACPI_FAILURE(acpi_processor_hotadd_init(pr)))
 327                         return -ENODEV;
 328         }
 329         /*
 330          * On some boxes several processors use the same processor bus id.
 331          * But they are located in different scope. For example:
 332          * \_SB.SCK0.CPU0
 333          * \_SB.SCK1.CPU0
 334          * Rename the processor device bus id. And the new bus id will be
 335          * generated as the following format:
 336          * CPU+CPU ID.
 337          */
 338         sprintf(acpi_device_bid(device), "CPU%X", pr->id);
 339         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
 340                           pr->acpi_id));
 341
 342         if (!object.processor.pblk_address)
 343                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
 344         else if (object.processor.pblk_length != 6)
 345                 printk(KERN_ERR PREFIX "Invalid PBLK length [%d]\n",
 346                             object.processor.pblk_length);
 347         else {
 348                 pr->throttling.address = object.processor.pblk_address;
 349                 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
 350                 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
 351
 352                 pr->pblk = object.processor.pblk_address;
 353
 354                 /*
 355                  * We don't care about error returns - we just try to mark
 356                  * these reserved so that nobody else is confused into thinking
 357                  * that this region might be unused..
 358                  *
 359                  * (In particular, allocating the IO range for Cardbus)
 360                  */
 361                 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
 362         }
 363
 364         /*
 365          * If ACPI describes a slot number for this CPU, we can use it
 366          * ensure we get the right value in the "physical id" field
 367          * of /proc/cpuinfo
 368          */
 369         status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer);
 370         if (ACPI_SUCCESS(status))
 371                 arch_fix_phys_package_id(pr->id, object.integer.value);
 372
 373         return 0;
 374 }
 375
 376 static DEFINE_PER_CPU(void *, processor_device_array);
 377
 378 static void acpi_processor_notify(struct acpi_device *device, u32 event)
 379 {
 380         struct acpi_processor *pr = acpi_driver_data(device);
 381         int saved;
 382
 383         if (!pr)
 384                 return;
 385
 386         switch (event) {
 387         case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
 388                 saved = pr->performance_platform_limit;
 389                 acpi_processor_ppc_has_changed(pr, 1);
 390                 if (saved == pr->performance_platform_limit)
 391                         break;
 392                 acpi_bus_generate_proc_event(device, event,
 393                                         pr->performance_platform_limit);
 394                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 395                                                   dev_name(&device->dev), event,
 396                                                   pr->performance_platform_limit);
 397                 break;
 398         case ACPI_PROCESSOR_NOTIFY_POWER:
 399                 acpi_processor_cst_has_changed(pr);
 400                 acpi_bus_generate_proc_event(device, event, 0);
 401                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 402                                                   dev_name(&device->dev), event, 0);
 403                 break;
 404         case ACPI_PROCESSOR_NOTIFY_THROTTLING:
 405                 acpi_processor_tstate_has_changed(pr);
 406                 acpi_bus_generate_proc_event(device, event, 0);
 407                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 408                                                   dev_name(&device->dev), event, 0);
 409         default:
 410                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 411                                   "Unsupported event [0x%x]\n", event));
 412                 break;
 413         }
 414
 415         return;
 416 }
 417
 418 static int acpi_cpu_soft_notify(struct notifier_block *nfb,
 419                 unsigned long action, void *hcpu)
 420 {
 421         unsigned int cpu = (unsigned long)hcpu;
 422         struct acpi_processor *pr = per_cpu(processors, cpu);
 423
 424         if (action == CPU_ONLINE && pr) {
 425                 /* CPU got physically hotplugged and onlined the first time:
 426                  * Initialize missing things
 427                  */
 428                 if (pr->flags.need_hotplug_init) {
 429                         struct cpuidle_driver *idle_driver =
 430                                 cpuidle_get_driver();
 431
 432                         printk(KERN_INFO "Will online and init hotplugged "
 433                                "CPU: %d\n", pr->id);
 434                         WARN(acpi_processor_start(pr), "Failed to start CPU:"
 435                                 " %d\n", pr->id);
 436                         pr->flags.need_hotplug_init = 0;
 437                         if (idle_driver && !strcmp(idle_driver->name,
 438                                                    "intel_idle")) {
 439                                 intel_idle_cpu_init(pr->id);
 440                         }
 441                 /* Normal CPU soft online event */
 442                 } else {
 443                         acpi_processor_ppc_has_changed(pr, 0);
 444                         acpi_processor_cst_has_changed(pr);
 445                         acpi_processor_reevaluate_tstate(pr, action);
 446                         acpi_processor_tstate_has_changed(pr);
 447                 }
 448         }
 449         if (action == CPU_DEAD && pr) {
 450                 /* invalidate the flag.throttling after one CPU is offline */
 451                 acpi_processor_reevaluate_tstate(pr, action);
 452         }
 453         return NOTIFY_OK;
 454 }
 455
 456 static struct notifier_block acpi_cpu_notifier =
 457 {
 458             .notifier_call = acpi_cpu_soft_notify,
 459 };
 460
 461 /*
 462  * acpi_processor_start() is called by the cpu_hotplug_notifier func:
 463  * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the
 464  * root cause seem to be that acpi_processor_uninstall_hotplug_notify()
 465  * is in the module_exit (__exit) func. Allowing acpi_processor_start()
 466  * to not be in __cpuinit section, but being called from __cpuinit funcs
 467  * via __ref looks like the right thing to do here.
 468  */
 469 static __ref int acpi_processor_start(struct acpi_processor *pr)
 470 {
 471         struct acpi_device *device = per_cpu(processor_device_array, pr->id);
 472         int result = 0;
 473
 474 #ifdef CONFIG_CPU_FREQ
 475         acpi_processor_ppc_has_changed(pr, 0);
 476         acpi_processor_load_module(pr);
 477 #endif
 478         acpi_processor_get_throttling_info(pr);
 479         acpi_processor_get_limit_info(pr);
 480
 481         if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
 482                 acpi_processor_power_init(pr, device);
 483
 484         pr->cdev = thermal_cooling_device_register("Processor", device,
 485                                                    &processor_cooling_ops);
 486         if (IS_ERR(pr->cdev)) {
 487                 result = PTR_ERR(pr->cdev);
 488                 goto err_power_exit;
 489         }
 490
 491         dev_dbg(&device->dev, "registered as cooling_device%d\n",
 492                 pr->cdev->id);
 493
 494         result = sysfs_create_link(&device->dev.kobj,
 495                                    &pr->cdev->device.kobj,
 496                                    "thermal_cooling");
 497         if (result) {
 498                 printk(KERN_ERR PREFIX "Create sysfs link\n");
 499                 goto err_thermal_unregister;
 500         }
 501         result = sysfs_create_link(&pr->cdev->device.kobj,
 502                                    &device->dev.kobj,
 503                                    "device");
 504         if (result) {
 505                 printk(KERN_ERR PREFIX "Create sysfs link\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, device);
 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                 kfree(pr);
 539                 return -ENOMEM;
 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) || (pr->id < 0));
 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                 printk(KERN_WARNING "BIOS reported wrong ACPI id "
 568                         "for the processor\n");
 569                 result = -ENODEV;
 570                 goto err_free_cpumask;
 571         }
 572         per_cpu(processor_device_array, pr->id) = device;
 573
 574         per_cpu(processors, pr->id) = pr;
 575
 576         dev = get_cpu_device(pr->id);
 577         if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
 578                 result = -EFAULT;
 579                 goto err_free_cpumask;
 580         }
 581
 582         /*
 583          * Do not start hotplugged CPUs now, but when they
 584          * are onlined the first time
 585          */
 586         if (pr->flags.need_hotplug_init)
 587                 return 0;
 588
 589         result = acpi_processor_start(pr);
 590         if (result)
 591                 goto err_remove_sysfs;
 592
 593         return 0;
 594
 595 err_remove_sysfs:
 596         sysfs_remove_link(&device->dev.kobj, "sysdev");
 597 err_free_cpumask:
 598         free_cpumask_var(pr->throttling.shared_cpu_map);
 599
 600         return result;
 601 }
 602
 603 static int acpi_processor_remove(struct acpi_device *device, int type)
 604 {
 605         struct acpi_processor *pr = NULL;
 606
 607
 608         if (!device || !acpi_driver_data(device))
 609                 return -EINVAL;
 610
 611         pr = acpi_driver_data(device);
 612
 613         if (pr->id >= nr_cpu_ids)
 614                 goto free;
 615
 616         if (type == ACPI_BUS_REMOVAL_EJECT) {
 617                 if (acpi_processor_handle_eject(pr))
 618                         return -EINVAL;
 619         }
 620
 621         acpi_processor_power_exit(pr, device);
 622
 623         sysfs_remove_link(&device->dev.kobj, "sysdev");
 624
 625         if (pr->cdev) {
 626                 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 627                 sysfs_remove_link(&pr->cdev->device.kobj, "device");
 628                 thermal_cooling_device_unregister(pr->cdev);
 629                 pr->cdev = NULL;
 630         }
 631
 632         per_cpu(processors, pr->id) = NULL;
 633         per_cpu(processor_device_array, pr->id) = NULL;
 634
 635 free:
 636         free_cpumask_var(pr->throttling.shared_cpu_map);
 637         kfree(pr);
 638
 639         return 0;
 640 }
 641
 642 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 643 /****************************************************************************
 644  *      Acpi processor hotplug support                                      *
 645  ****************************************************************************/
 646
 647 static int is_processor_present(acpi_handle handle)
 648 {
 649         acpi_status status;
 650         unsigned long long sta = 0;
 651
 652
 653         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 654
 655         if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
 656                 return 1;
 657
 658         /*
 659          * _STA is mandatory for a processor that supports hot plug
 660          */
 661         if (status == AE_NOT_FOUND)
 662                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 663                                 "Processor does not support hot plug\n"));
 664         else
 665                 ACPI_EXCEPTION((AE_INFO, status,
 666                                 "Processor Device is not present"));
 667         return 0;
 668 }
 669
 670 static
 671 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
 672 {
 673         acpi_handle phandle;
 674         struct acpi_device *pdev;
 675
 676
 677         if (acpi_get_parent(handle, &phandle)) {
 678                 return -ENODEV;
 679         }
 680
 681         if (acpi_bus_get_device(phandle, &pdev)) {
 682                 return -ENODEV;
 683         }
 684
 685         if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
 686                 return -ENODEV;
 687         }
 688
 689         return 0;
 690 }
 691
 692 static void acpi_processor_hotplug_notify(acpi_handle handle,
 693                                           u32 event, void *data)
 694 {
 695         struct acpi_processor *pr;
 696         struct acpi_device *device = NULL;
 697         int result;
 698
 699
 700         switch (event) {
 701         case ACPI_NOTIFY_BUS_CHECK:
 702         case ACPI_NOTIFY_DEVICE_CHECK:
 703                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 704                 "Processor driver received %s event\n",
 705                        (event == ACPI_NOTIFY_BUS_CHECK) ?
 706                        "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK"));
 707
 708                 if (!is_processor_present(handle))
 709                         break;
 710
 711                 if (acpi_bus_get_device(handle, &device)) {
 712                         result = acpi_processor_device_add(handle, &device);
 713                         if (result)
 714                                 printk(KERN_ERR PREFIX
 715                                             "Unable to add the device\n");
 716                         break;
 717                 }
 718                 break;
 719         case ACPI_NOTIFY_EJECT_REQUEST:
 720                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 721                                   "received ACPI_NOTIFY_EJECT_REQUEST\n"));
 722
 723                 if (acpi_bus_get_device(handle, &device)) {
 724                         printk(KERN_ERR PREFIX
 725                                     "Device don't exist, dropping EJECT\n");
 726                         break;
 727                 }
 728                 pr = acpi_driver_data(device);
 729                 if (!pr) {
 730                         printk(KERN_ERR PREFIX
 731                                     "Driver data is NULL, dropping EJECT\n");
 732                         return;
 733                 }
 734                 break;
 735         default:
 736                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 737                                   "Unsupported event [0x%x]\n", event));
 738                 break;
 739         }
 740
 741         return;
 742 }
 743
 744 static acpi_status
 745 processor_walk_namespace_cb(acpi_handle handle,
 746                             u32 lvl, void *context, void **rv)
 747 {
 748         acpi_status status;
 749         int *action = context;
 750         acpi_object_type type = 0;
 751
 752         status = acpi_get_type(handle, &type);
 753         if (ACPI_FAILURE(status))
 754                 return (AE_OK);
 755
 756         if (type != ACPI_TYPE_PROCESSOR)
 757                 return (AE_OK);
 758
 759         switch (*action) {
 760         case INSTALL_NOTIFY_HANDLER:
 761                 acpi_install_notify_handler(handle,
 762                                             ACPI_SYSTEM_NOTIFY,
 763                                             acpi_processor_hotplug_notify,
 764                                             NULL);
 765                 break;
 766         case UNINSTALL_NOTIFY_HANDLER:
 767                 acpi_remove_notify_handler(handle,
 768                                            ACPI_SYSTEM_NOTIFY,
 769                                            acpi_processor_hotplug_notify);
 770                 break;
 771         default:
 772                 break;
 773         }
 774
 775         return (AE_OK);
 776 }
 777
 778 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 779 {
 780         acpi_handle handle = pr->handle;
 781
 782         if (!is_processor_present(handle)) {
 783                 return AE_ERROR;
 784         }
 785
 786         if (acpi_map_lsapic(handle, &pr->id))
 787                 return AE_ERROR;
 788
 789         if (arch_register_cpu(pr->id)) {
 790                 acpi_unmap_lsapic(pr->id);
 791                 return AE_ERROR;
 792         }
 793
 794         /* CPU got hot-plugged, but cpu_data is not initialized yet
 795          * Set flag to delay cpu_idle/throttling initialization
 796          * in:
 797          * acpi_processor_add()
 798          *   acpi_processor_get_info()
 799          * and do it when the CPU gets online the first time
 800          * TBD: Cleanup above functions and try to do this more elegant.
 801          */
 802         printk(KERN_INFO "CPU %d got hotplugged\n", pr->id);
 803         pr->flags.need_hotplug_init = 1;
 804
 805         return AE_OK;
 806 }
 807
 808 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 809 {
 810         if (cpu_online(pr->id))
 811                 cpu_down(pr->id);
 812
 813         arch_unregister_cpu(pr->id);
 814         acpi_unmap_lsapic(pr->id);
 815         return (0);
 816 }
 817 #else
 818 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 819 {
 820         return AE_ERROR;
 821 }
 822 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 823 {
 824         return (-EINVAL);
 825 }
 826 #endif
 827
 828 static
 829 void acpi_processor_install_hotplug_notify(void)
 830 {
 831 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 832         int action = INSTALL_NOTIFY_HANDLER;
 833         acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
 834                             ACPI_ROOT_OBJECT,
 835                             ACPI_UINT32_MAX,
 836                             processor_walk_namespace_cb, NULL, &action, NULL);
 837 #endif
 838         register_hotcpu_notifier(&acpi_cpu_notifier);
 839 }
 840
 841 static
 842 void acpi_processor_uninstall_hotplug_notify(void)
 843 {
 844 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 845         int action = UNINSTALL_NOTIFY_HANDLER;
 846         acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
 847                             ACPI_ROOT_OBJECT,
 848                             ACPI_UINT32_MAX,
 849                             processor_walk_namespace_cb, NULL, &action, NULL);
 850 #endif
 851         unregister_hotcpu_notifier(&acpi_cpu_notifier);
 852 }
 853
 854 /*
 855  * We keep the driver loaded even when ACPI is not running.
 856  * This is needed for the powernow-k8 driver, that works even without
 857  * ACPI, but needs symbols from this driver
 858  */
 859
 860 static int __init acpi_processor_init(void)
 861 {
 862         int result = 0;
 863
 864         if (acpi_disabled)
 865                 return 0;
 866
 867         memset(&errata, 0, sizeof(errata));
 868
 869         result = acpi_bus_register_driver(&acpi_processor_driver);
 870         if (result < 0)
 871                 return result;
 872
 873         acpi_processor_install_hotplug_notify();
 874
 875         acpi_thermal_cpufreq_init();
 876
 877         acpi_processor_ppc_init();
 878
 879         acpi_processor_throttling_init();
 880
 881         return 0;
 882 }
 883
 884 static void __exit acpi_processor_exit(void)
 885 {
 886         if (acpi_disabled)
 887                 return;
 888
 889         acpi_processor_ppc_exit();
 890
 891         acpi_thermal_cpufreq_exit();
 892
 893         acpi_processor_uninstall_hotplug_notify();
 894
 895         acpi_bus_unregister_driver(&acpi_processor_driver);
 896
 897         return;
 898 }
 899
 900 module_init(acpi_processor_init);
 901 module_exit(acpi_processor_exit);
 902
 903 MODULE_ALIAS("processor");