linux/drivers/acpi/processor_driver.c
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   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
  76ACPI_MODULE_NAME("processor_driver");
  77
  78MODULE_AUTHOR("Paul Diefenbaugh");
  79MODULE_DESCRIPTION("ACPI Processor Driver");
  80MODULE_LICENSE("GPL");
  81
  82static int acpi_processor_add(struct acpi_device *device);
  83static int acpi_processor_remove(struct acpi_device *device, int type);
  84static void acpi_processor_notify(struct acpi_device *device, u32 event);
  85static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr);
  86static int acpi_processor_handle_eject(struct acpi_processor *pr);
  87static int acpi_processor_start(struct acpi_processor *pr);
  88
  89static const struct acpi_device_id processor_device_ids[] = {
  90        {ACPI_PROCESSOR_OBJECT_HID, 0},
  91        {ACPI_PROCESSOR_DEVICE_HID, 0},
  92        {"", 0},
  93};
  94MODULE_DEVICE_TABLE(acpi, processor_device_ids);
  95
  96static SIMPLE_DEV_PM_OPS(acpi_processor_pm,
  97                         acpi_processor_suspend, acpi_processor_resume);
  98
  99static 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
 114DEFINE_PER_CPU(struct acpi_processor *, processors);
 115EXPORT_PER_CPU_SYMBOL(processors);
 116
 117struct acpi_processor_errata errata __read_mostly;
 118
 119/* --------------------------------------------------------------------------
 120                                Errata Handling
 121   -------------------------------------------------------------------------- */
 122
 123static 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
 224static 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
 251static 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
 379static DEFINE_PER_CPU(void *, processor_device_array);
 380
 381static 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
 421static 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
 452static 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 */
 465static __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, device);
 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
 507err_remove_sysfs_thermal:
 508        sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 509err_thermal_unregister:
 510        thermal_cooling_device_unregister(pr->cdev);
 511err_power_exit:
 512        acpi_processor_power_exit(pr, device);
 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 */
 523static 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
 591err_remove_sysfs:
 592        sysfs_remove_link(&device->dev.kobj, "sysdev");
 593err_clear_processor:
 594        /*
 595         * processor_device_array is not cleared to allow checks for buggy BIOS
 596         */ 
 597        per_cpu(processors, pr->id) = NULL;
 598err_free_cpumask:
 599        free_cpumask_var(pr->throttling.shared_cpu_map);
 600err_free_pr:
 601        kfree(pr);
 602        return result;
 603}
 604
 605static 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, device);
 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
 637free:
 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
 649static 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
 672static
 673int 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
 694static 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
 758static 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
 788static acpi_status
 789processor_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
 819static 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
 849static 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
 859static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 860{
 861        return AE_ERROR;
 862}
 863static int acpi_processor_handle_eject(struct acpi_processor *pr)
 864{
 865        return (-EINVAL);
 866}
 867#endif
 868
 869static
 870void 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
 882static
 883void 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
 901static int __init acpi_processor_init(void)
 902{
 903        int result = 0;
 904
 905        if (acpi_disabled)
 906                return 0;
 907
 908        memset(&errata, 0, sizeof(errata));
 909
 910        result = acpi_bus_register_driver(&acpi_processor_driver);
 911        if (result < 0)
 912                return result;
 913
 914        acpi_processor_install_hotplug_notify();
 915
 916        acpi_thermal_cpufreq_init();
 917
 918        acpi_processor_ppc_init();
 919
 920        acpi_processor_throttling_init();
 921
 922        return 0;
 923}
 924
 925static void __exit acpi_processor_exit(void)
 926{
 927        if (acpi_disabled)
 928                return;
 929
 930        acpi_processor_ppc_exit();
 931
 932        acpi_thermal_cpufreq_exit();
 933
 934        acpi_processor_uninstall_hotplug_notify();
 935
 936        acpi_bus_unregister_driver(&acpi_processor_driver);
 937
 938        return;
 939}
 940
 941module_init(acpi_processor_init);
 942module_exit(acpi_processor_exit);
 943
 944MODULE_ALIAS("processor");
 945
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