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                 break;
 413         default:
 414                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 415                                   "Unsupported event [0x%x]\n", event));
 416                 break;
 417         }
 418
 419         return;
 420 }
 421
 422 static int acpi_cpu_soft_notify(struct notifier_block *nfb,
 423                 unsigned long action, void *hcpu)
 424 {
 425         unsigned int cpu = (unsigned long)hcpu;
 426         struct acpi_processor *pr = per_cpu(processors, cpu);
 427
 428         if (action == CPU_ONLINE && pr) {
 429                 /* CPU got physically hotplugged and onlined the first time:
 430                  * Initialize missing things
 431                  */
 432                 if (pr->flags.need_hotplug_init) {
 433                         printk(KERN_INFO "Will online and init hotplugged "
 434                                "CPU: %d\n", pr->id);
 435                         WARN(acpi_processor_start(pr), "Failed to start CPU:"
 436                                 " %d\n", pr->id);
 437                         pr->flags.need_hotplug_init = 0;
 438                 /* Normal CPU soft online event */
 439                 } else {
 440                         acpi_processor_ppc_has_changed(pr, 0);
 441                         acpi_processor_hotplug(pr);
 442                         acpi_processor_reevaluate_tstate(pr, action);
 443                         acpi_processor_tstate_has_changed(pr);
 444                 }
 445         }
 446         if (action == CPU_DEAD && pr) {
 447                 /* invalidate the flag.throttling after one CPU is offline */
 448                 acpi_processor_reevaluate_tstate(pr, action);
 449         }
 450         return NOTIFY_OK;
 451 }
 452
 453 static struct notifier_block acpi_cpu_notifier =
 454 {
 455             .notifier_call = acpi_cpu_soft_notify,
 456 };
 457
 458 /*
 459  * acpi_processor_start() is called by the cpu_hotplug_notifier func:
 460  * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the
 461  * root cause seem to be that acpi_processor_uninstall_hotplug_notify()
 462  * is in the module_exit (__exit) func. Allowing acpi_processor_start()
 463  * to not be in __cpuinit section, but being called from __cpuinit funcs
 464  * via __ref looks like the right thing to do here.
 465  */
 466 static __ref int acpi_processor_start(struct acpi_processor *pr)
 467 {
 468         struct acpi_device *device = per_cpu(processor_device_array, pr->id);
 469         int result = 0;
 470
 471 #ifdef CONFIG_CPU_FREQ
 472         acpi_processor_ppc_has_changed(pr, 0);
 473         acpi_processor_load_module(pr);
 474 #endif
 475         acpi_processor_get_throttling_info(pr);
 476         acpi_processor_get_limit_info(pr);
 477
 478         if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
 479                 acpi_processor_power_init(pr);
 480
 481         pr->cdev = thermal_cooling_device_register("Processor", device,
 482                                                    &processor_cooling_ops);
 483         if (IS_ERR(pr->cdev)) {
 484                 result = PTR_ERR(pr->cdev);
 485                 goto err_power_exit;
 486         }
 487
 488         dev_dbg(&device->dev, "registered as cooling_device%d\n",
 489                 pr->cdev->id);
 490
 491         result = sysfs_create_link(&device->dev.kobj,
 492                                    &pr->cdev->device.kobj,
 493                                    "thermal_cooling");
 494         if (result) {
 495                 printk(KERN_ERR PREFIX "Create sysfs link\n");
 496                 goto err_thermal_unregister;
 497         }
 498         result = sysfs_create_link(&pr->cdev->device.kobj,
 499                                    &device->dev.kobj,
 500                                    "device");
 501         if (result) {
 502                 printk(KERN_ERR PREFIX "Create sysfs link\n");
 503                 goto err_remove_sysfs_thermal;
 504         }
 505
 506         return 0;
 507
 508 err_remove_sysfs_thermal:
 509         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 510 err_thermal_unregister:
 511         thermal_cooling_device_unregister(pr->cdev);
 512 err_power_exit:
 513         acpi_processor_power_exit(pr);
 514
 515         return result;
 516 }
 517
 518 /*
 519  * Do not put anything in here which needs the core to be online.
 520  * For example MSR access or setting up things which check for cpuinfo_x86
 521  * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
 522  * Such things have to be put in and set up above in acpi_processor_start()
 523  */
 524 static int __cpuinit acpi_processor_add(struct acpi_device *device)
 525 {
 526         struct acpi_processor *pr = NULL;
 527         int result = 0;
 528         struct device *dev;
 529
 530         pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
 531         if (!pr)
 532                 return -ENOMEM;
 533
 534         if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
 535                 result = -ENOMEM;
 536                 goto err_free_pr;
 537         }
 538
 539         pr->handle = device->handle;
 540         strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 541         strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
 542         device->driver_data = pr;
 543
 544         result = acpi_processor_get_info(device);
 545         if (result) {
 546                 /* Processor is physically not present */
 547                 return 0;
 548         }
 549
 550 #ifdef CONFIG_SMP
 551         if (pr->id >= setup_max_cpus && pr->id != 0)
 552                 return 0;
 553 #endif
 554
 555         BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0));
 556
 557         /*
 558          * Buggy BIOS check
 559          * ACPI id of processors can be reported wrongly by the BIOS.
 560          * Don't trust it blindly
 561          */
 562         if (per_cpu(processor_device_array, pr->id) != NULL &&
 563             per_cpu(processor_device_array, pr->id) != device) {
 564                 printk(KERN_WARNING "BIOS reported wrong ACPI id "
 565                         "for the processor\n");
 566                 result = -ENODEV;
 567                 goto err_free_cpumask;
 568         }
 569         per_cpu(processor_device_array, pr->id) = device;
 570
 571         per_cpu(processors, pr->id) = pr;
 572
 573         dev = get_cpu_device(pr->id);
 574         if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
 575                 result = -EFAULT;
 576                 goto err_clear_processor;
 577         }
 578
 579         /*
 580          * Do not start hotplugged CPUs now, but when they
 581          * are onlined the first time
 582          */
 583         if (pr->flags.need_hotplug_init)
 584                 return 0;
 585
 586         result = acpi_processor_start(pr);
 587         if (result)
 588                 goto err_remove_sysfs;
 589
 590         return 0;
 591
 592 err_remove_sysfs:
 593         sysfs_remove_link(&device->dev.kobj, "sysdev");
 594 err_clear_processor:
 595         /*
 596          * processor_device_array is not cleared to allow checks for buggy BIOS
 597          */
 598         per_cpu(processors, pr->id) = NULL;
 599 err_free_cpumask:
 600         free_cpumask_var(pr->throttling.shared_cpu_map);
 601 err_free_pr:
 602         kfree(pr);
 603         return result;
 604 }
 605
 606 static int acpi_processor_remove(struct acpi_device *device, int type)
 607 {
 608         struct acpi_processor *pr = NULL;
 609
 610
 611         if (!device || !acpi_driver_data(device))
 612                 return -EINVAL;
 613
 614         pr = acpi_driver_data(device);
 615
 616         if (pr->id >= nr_cpu_ids)
 617                 goto free;
 618
 619         if (type == ACPI_BUS_REMOVAL_EJECT) {
 620                 if (acpi_processor_handle_eject(pr))
 621                         return -EINVAL;
 622         }
 623
 624         acpi_processor_power_exit(pr);
 625
 626         sysfs_remove_link(&device->dev.kobj, "sysdev");
 627
 628         if (pr->cdev) {
 629                 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 630                 sysfs_remove_link(&pr->cdev->device.kobj, "device");
 631                 thermal_cooling_device_unregister(pr->cdev);
 632                 pr->cdev = NULL;
 633         }
 634
 635         per_cpu(processors, pr->id) = NULL;
 636         per_cpu(processor_device_array, pr->id) = NULL;
 637
 638 free:
 639         free_cpumask_var(pr->throttling.shared_cpu_map);
 640         kfree(pr);
 641
 642         return 0;
 643 }
 644
 645 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 646 /****************************************************************************
 647  *      Acpi processor hotplug support                                      *
 648  ****************************************************************************/
 649
 650 static int is_processor_present(acpi_handle handle)
 651 {
 652         acpi_status status;
 653         unsigned long long sta = 0;
 654
 655
 656         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 657
 658         if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
 659                 return 1;
 660
 661         /*
 662          * _STA is mandatory for a processor that supports hot plug
 663          */
 664         if (status == AE_NOT_FOUND)
 665                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 666                                 "Processor does not support hot plug\n"));
 667         else
 668                 ACPI_EXCEPTION((AE_INFO, status,
 669                                 "Processor Device is not present"));
 670         return 0;
 671 }
 672
 673 static
 674 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
 675 {
 676         acpi_handle phandle;
 677         struct acpi_device *pdev;
 678
 679
 680         if (acpi_get_parent(handle, &phandle)) {
 681                 return -ENODEV;
 682         }
 683
 684         if (acpi_bus_get_device(phandle, &pdev)) {
 685                 return -ENODEV;
 686         }
 687
 688         if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
 689                 return -ENODEV;
 690         }
 691
 692         return 0;
 693 }
 694
 695 static void acpi_processor_hotplug_notify(acpi_handle handle,
 696                                           u32 event, void *data)
 697 {
 698         struct acpi_processor *pr;
 699         struct acpi_device *device = NULL;
 700         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
 701         int result;
 702
 703         switch (event) {
 704         case ACPI_NOTIFY_BUS_CHECK:
 705         case ACPI_NOTIFY_DEVICE_CHECK:
 706                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 707                 "Processor driver received %s event\n",
 708                        (event == ACPI_NOTIFY_BUS_CHECK) ?
 709                        "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK"));
 710
 711                 if (!is_processor_present(handle))
 712                         break;
 713
 714                 if (!acpi_bus_get_device(handle, &device))
 715                         break;
 716
 717                 result = acpi_processor_device_add(handle, &device);
 718                 if (result) {
 719                         printk(KERN_ERR PREFIX "Unable to add the device\n");
 720                         break;
 721                 }
 722
 723                 ost_code = ACPI_OST_SC_SUCCESS;
 724                 break;
 725
 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                         break;
 740                 }
 741
 742                 /* REVISIT: update when eject is supported */
 743                 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
 744                 break;
 745
 746         default:
 747                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 748                                   "Unsupported event [0x%x]\n", event));
 749
 750                 /* non-hotplug event; possibly handled by other handler */
 751                 return;
 752         }
 753
 754         /* Inform firmware that the hotplug operation has completed */
 755         (void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL);
 756         return;
 757 }
 758
 759 static acpi_status is_processor_device(acpi_handle handle)
 760 {
 761         struct acpi_device_info *info;
 762         char *hid;
 763         acpi_status status;
 764
 765         status = acpi_get_object_info(handle, &info);
 766         if (ACPI_FAILURE(status))
 767                 return status;
 768
 769         if (info->type == ACPI_TYPE_PROCESSOR) {
 770                 kfree(info);
 771                 return AE_OK;   /* found a processor object */
 772         }
 773
 774         if (!(info->valid & ACPI_VALID_HID)) {
 775                 kfree(info);
 776                 return AE_ERROR;
 777         }
 778
 779         hid = info->hardware_id.string;
 780         if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) {
 781                 kfree(info);
 782                 return AE_ERROR;
 783         }
 784
 785         kfree(info);
 786         return AE_OK;   /* found a processor device object */
 787 }
 788
 789 static acpi_status
 790 processor_walk_namespace_cb(acpi_handle handle,
 791                             u32 lvl, void *context, void **rv)
 792 {
 793         acpi_status status;
 794         int *action = context;
 795
 796         status = is_processor_device(handle);
 797         if (ACPI_FAILURE(status))
 798                 return AE_OK;   /* not a processor; continue to walk */
 799
 800         switch (*action) {
 801         case INSTALL_NOTIFY_HANDLER:
 802                 acpi_install_notify_handler(handle,
 803                                             ACPI_SYSTEM_NOTIFY,
 804                                             acpi_processor_hotplug_notify,
 805                                             NULL);
 806                 break;
 807         case UNINSTALL_NOTIFY_HANDLER:
 808                 acpi_remove_notify_handler(handle,
 809                                            ACPI_SYSTEM_NOTIFY,
 810                                            acpi_processor_hotplug_notify);
 811                 break;
 812         default:
 813                 break;
 814         }
 815
 816         /* found a processor; skip walking underneath */
 817         return AE_CTRL_DEPTH;
 818 }
 819
 820 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 821 {
 822         acpi_handle handle = pr->handle;
 823
 824         if (!is_processor_present(handle)) {
 825                 return AE_ERROR;
 826         }
 827
 828         if (acpi_map_lsapic(handle, &pr->id))
 829                 return AE_ERROR;
 830
 831         if (arch_register_cpu(pr->id)) {
 832                 acpi_unmap_lsapic(pr->id);
 833                 return AE_ERROR;
 834         }
 835
 836         /* CPU got hot-plugged, but cpu_data is not initialized yet
 837          * Set flag to delay cpu_idle/throttling initialization
 838          * in:
 839          * acpi_processor_add()
 840          *   acpi_processor_get_info()
 841          * and do it when the CPU gets online the first time
 842          * TBD: Cleanup above functions and try to do this more elegant.
 843          */
 844         printk(KERN_INFO "CPU %d got hotplugged\n", pr->id);
 845         pr->flags.need_hotplug_init = 1;
 846
 847         return AE_OK;
 848 }
 849
 850 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 851 {
 852         if (cpu_online(pr->id))
 853                 cpu_down(pr->id);
 854
 855         arch_unregister_cpu(pr->id);
 856         acpi_unmap_lsapic(pr->id);
 857         return (0);
 858 }
 859 #else
 860 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 861 {
 862         return AE_ERROR;
 863 }
 864 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 865 {
 866         return (-EINVAL);
 867 }
 868 #endif
 869
 870 static
 871 void acpi_processor_install_hotplug_notify(void)
 872 {
 873 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 874         int action = INSTALL_NOTIFY_HANDLER;
 875         acpi_walk_namespace(ACPI_TYPE_ANY,
 876                             ACPI_ROOT_OBJECT,
 877                             ACPI_UINT32_MAX,
 878                             processor_walk_namespace_cb, NULL, &action, NULL);
 879 #endif
 880         register_hotcpu_notifier(&acpi_cpu_notifier);
 881 }
 882
 883 static
 884 void acpi_processor_uninstall_hotplug_notify(void)
 885 {
 886 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 887         int action = UNINSTALL_NOTIFY_HANDLER;
 888         acpi_walk_namespace(ACPI_TYPE_ANY,
 889                             ACPI_ROOT_OBJECT,
 890                             ACPI_UINT32_MAX,
 891                             processor_walk_namespace_cb, NULL, &action, NULL);
 892 #endif
 893         unregister_hotcpu_notifier(&acpi_cpu_notifier);
 894 }
 895
 896 /*
 897  * We keep the driver loaded even when ACPI is not running.
 898  * This is needed for the powernow-k8 driver, that works even without
 899  * ACPI, but needs symbols from this driver
 900  */
 901
 902 static int __init acpi_processor_init(void)
 903 {
 904         int result = 0;
 905
 906         if (acpi_disabled)
 907                 return 0;
 908
 909         result = acpi_bus_register_driver(&acpi_processor_driver);
 910         if (result < 0)
 911                 return result;
 912
 913         acpi_processor_install_hotplug_notify();
 914
 915         acpi_thermal_cpufreq_init();
 916
 917         acpi_processor_ppc_init();
 918
 919         acpi_processor_throttling_init();
 920
 921         return 0;
 922 }
 923
 924 static void __exit acpi_processor_exit(void)
 925 {
 926         if (acpi_disabled)
 927                 return;
 928
 929         acpi_processor_ppc_exit();
 930
 931         acpi_thermal_cpufreq_exit();
 932
 933         acpi_processor_uninstall_hotplug_notify();
 934
 935         acpi_bus_unregister_driver(&acpi_processor_driver);
 936
 937         return;
 938 }
 939
 940 module_init(acpi_processor_init);
 941 module_exit(acpi_processor_exit);
 942
 943 MODULE_ALIAS("processor");