linux/drivers/acpi/processor_driver.c
<<
>>
Prefs
   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                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
 422static 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
 453static 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 */
 466static __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
 508err_remove_sysfs_thermal:
 509        sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 510err_thermal_unregister:
 511        thermal_cooling_device_unregister(pr->cdev);
 512err_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 */
 524static 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
 592err_remove_sysfs:
 593        sysfs_remove_link(&device->dev.kobj, "sysdev");
 594err_clear_processor:
 595        /*
 596         * processor_device_array is not cleared to allow checks for buggy BIOS
 597         */ 
 598        per_cpu(processors, pr->id) = NULL;
 599err_free_cpumask:
 600        free_cpumask_var(pr->throttling.shared_cpu_map);
 601err_free_pr:
 602        kfree(pr);
 603        return result;
 604}
 605
 606static 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
 638free:
 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
 650static 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
 673static
 674int 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
 695static 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
 759static 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
 789static acpi_status
 790processor_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
 820static 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
 850static 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
 860static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
 861{
 862        return AE_ERROR;
 863}
 864static int acpi_processor_handle_eject(struct acpi_processor *pr)
 865{
 866        return (-EINVAL);
 867}
 868#endif
 869
 870static
 871void 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
 883static
 884void 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
 902static 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
 924static 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
 940module_init(acpi_processor_init);
 941module_exit(acpi_processor_exit);
 942
 943MODULE_ALIAS("processor");
 944
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.