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