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