drivers/acpi/processor_core.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/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/dmi.h>
  46 #include <linux/moduleparam.h>
  47
  48 #include <asm/io.h>
  49 #include <asm/system.h>
  50 #include <asm/cpu.h>
  51 #include <asm/delay.h>
  52 #include <asm/uaccess.h>
  53 #include <asm/processor.h>
  54 #include <asm/smp.h>
  55 #include <asm/acpi.h>
  56
  57 #include <acpi/acpi_bus.h>
  58 #include <acpi/acpi_drivers.h>
  59 #include <acpi/processor.h>
  60
  61 #define ACPI_PROCESSOR_COMPONENT        0x01000000
  62 #define ACPI_PROCESSOR_CLASS            "processor"
  63 #define ACPI_PROCESSOR_DRIVER_NAME      "ACPI Processor Driver"
  64 #define ACPI_PROCESSOR_DEVICE_NAME      "Processor"
  65 #define ACPI_PROCESSOR_FILE_INFO        "info"
  66 #define ACPI_PROCESSOR_FILE_THROTTLING  "throttling"
  67 #define ACPI_PROCESSOR_FILE_LIMIT       "limit"
  68 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
  69 #define ACPI_PROCESSOR_NOTIFY_POWER     0x81
  70
  71 #define ACPI_PROCESSOR_LIMIT_USER       0
  72 #define ACPI_PROCESSOR_LIMIT_THERMAL    1
  73
  74 #define ACPI_STA_PRESENT 0x00000001
  75
  76 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
  77 ACPI_MODULE_NAME("acpi_processor")
  78
  79     MODULE_AUTHOR("Paul Diefenbaugh");
  80 MODULE_DESCRIPTION(ACPI_PROCESSOR_DRIVER_NAME);
  81 MODULE_LICENSE("GPL");
  82
  83 static int acpi_processor_add(struct acpi_device *device);
  84 static int acpi_processor_start(struct acpi_device *device);
  85 static int acpi_processor_remove(struct acpi_device *device, int type);
  86 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file);
  87 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data);
  88 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu);
  89 static int acpi_processor_handle_eject(struct acpi_processor *pr);
  90
  91 static struct acpi_driver acpi_processor_driver = {
  92         .name = ACPI_PROCESSOR_DRIVER_NAME,
  93         .class = ACPI_PROCESSOR_CLASS,
  94         .ids = ACPI_PROCESSOR_HID,
  95         .ops = {
  96                 .add = acpi_processor_add,
  97                 .remove = acpi_processor_remove,
  98                 .start = acpi_processor_start,
  99                 },
 100 };
 101
 102 #define INSTALL_NOTIFY_HANDLER          1
 103 #define UNINSTALL_NOTIFY_HANDLER        2
 104
 105 static struct file_operations acpi_processor_info_fops = {
 106         .open = acpi_processor_info_open_fs,
 107         .read = seq_read,
 108         .llseek = seq_lseek,
 109         .release = single_release,
 110 };
 111
 112 struct acpi_processor *processors[NR_CPUS];
 113 struct acpi_processor_errata errata;
 114
 115 /* --------------------------------------------------------------------------
 116                                 Errata Handling
 117    -------------------------------------------------------------------------- */
 118
 119 static int acpi_processor_errata_piix4(struct pci_dev *dev)
 120 {
 121         u8 rev = 0;
 122         u8 value1 = 0;
 123         u8 value2 = 0;
 124
 125         ACPI_FUNCTION_TRACE("acpi_processor_errata_piix4");
 126
 127         if (!dev)
 128                 return_VALUE(-EINVAL);
 129
 130         /*
 131          * Note that 'dev' references the PIIX4 ACPI Controller.
 132          */
 133
 134         pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
 135
 136         switch (rev) {
 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 (rev) {
 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_VALUE(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         ACPI_FUNCTION_TRACE("acpi_processor_errata");
 230
 231         if (!pr)
 232                 return_VALUE(-EINVAL);
 233
 234         /*
 235          * PIIX4
 236          */
 237         dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 238                              PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
 239                              PCI_ANY_ID, NULL);
 240         if (dev) {
 241                 result = acpi_processor_errata_piix4(dev);
 242                 pci_dev_put(dev);
 243         }
 244
 245         return_VALUE(result);
 246 }
 247
 248 /* --------------------------------------------------------------------------
 249                               Common ACPI processor fucntions
 250    -------------------------------------------------------------------------- */
 251
 252 /*
 253  * _PDC is required for a BIOS-OS handshake for most of the newer
 254  * ACPI processor features.
 255  */
 256 static int acpi_processor_set_pdc(struct acpi_processor *pr)
 257 {
 258         struct acpi_object_list *pdc_in = pr->pdc;
 259         acpi_status status = AE_OK;
 260
 261         ACPI_FUNCTION_TRACE("acpi_processor_set_pdc");
 262
 263         if (!pdc_in)
 264                 return_VALUE(status);
 265
 266         status = acpi_evaluate_object(pr->handle, "_PDC", pdc_in, NULL);
 267
 268         if (ACPI_FAILURE(status))
 269                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 270                     "Could not evaluate _PDC, using legacy perf. control...\n"));
 271
 272         return_VALUE(status);
 273 }
 274
 275 /* --------------------------------------------------------------------------
 276                               FS Interface (/proc)
 277    -------------------------------------------------------------------------- */
 278
 279 static struct proc_dir_entry *acpi_processor_dir = NULL;
 280
 281 static int acpi_processor_info_seq_show(struct seq_file *seq, void *offset)
 282 {
 283         struct acpi_processor *pr = (struct acpi_processor *)seq->private;
 284
 285         ACPI_FUNCTION_TRACE("acpi_processor_info_seq_show");
 286
 287         if (!pr)
 288                 goto end;
 289
 290         seq_printf(seq, "processor id:            %d\n"
 291                    "acpi id:                 %d\n"
 292                    "bus mastering control:   %s\n"
 293                    "power management:        %s\n"
 294                    "throttling control:      %s\n"
 295                    "limit interface:         %s\n",
 296                    pr->id,
 297                    pr->acpi_id,
 298                    pr->flags.bm_control ? "yes" : "no",
 299                    pr->flags.power ? "yes" : "no",
 300                    pr->flags.throttling ? "yes" : "no",
 301                    pr->flags.limit ? "yes" : "no");
 302
 303       end:
 304         return_VALUE(0);
 305 }
 306
 307 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file)
 308 {
 309         return single_open(file, acpi_processor_info_seq_show,
 310                            PDE(inode)->data);
 311 }
 312
 313 static int acpi_processor_add_fs(struct acpi_device *device)
 314 {
 315         struct proc_dir_entry *entry = NULL;
 316
 317         ACPI_FUNCTION_TRACE("acpi_processor_add_fs");
 318
 319         if (!acpi_device_dir(device)) {
 320                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 321                                                      acpi_processor_dir);
 322                 if (!acpi_device_dir(device))
 323                         return_VALUE(-ENODEV);
 324         }
 325         acpi_device_dir(device)->owner = THIS_MODULE;
 326
 327         /* 'info' [R] */
 328         entry = create_proc_entry(ACPI_PROCESSOR_FILE_INFO,
 329                                   S_IRUGO, acpi_device_dir(device));
 330         if (!entry)
 331                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 332                                   "Unable to create '%s' fs entry\n",
 333                                   ACPI_PROCESSOR_FILE_INFO));
 334         else {
 335                 entry->proc_fops = &acpi_processor_info_fops;
 336                 entry->data = acpi_driver_data(device);
 337                 entry->owner = THIS_MODULE;
 338         }
 339
 340         /* 'throttling' [R/W] */
 341         entry = create_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
 342                                   S_IFREG | S_IRUGO | S_IWUSR,
 343                                   acpi_device_dir(device));
 344         if (!entry)
 345                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 346                                   "Unable to create '%s' fs entry\n",
 347                                   ACPI_PROCESSOR_FILE_THROTTLING));
 348         else {
 349                 entry->proc_fops = &acpi_processor_throttling_fops;
 350                 entry->proc_fops->write = acpi_processor_write_throttling;
 351                 entry->data = acpi_driver_data(device);
 352                 entry->owner = THIS_MODULE;
 353         }
 354
 355         /* 'limit' [R/W] */
 356         entry = create_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
 357                                   S_IFREG | S_IRUGO | S_IWUSR,
 358                                   acpi_device_dir(device));
 359         if (!entry)
 360                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 361                                   "Unable to create '%s' fs entry\n",
 362                                   ACPI_PROCESSOR_FILE_LIMIT));
 363         else {
 364                 entry->proc_fops = &acpi_processor_limit_fops;
 365                 entry->proc_fops->write = acpi_processor_write_limit;
 366                 entry->data = acpi_driver_data(device);
 367                 entry->owner = THIS_MODULE;
 368         }
 369
 370         return_VALUE(0);
 371 }
 372
 373 static int acpi_processor_remove_fs(struct acpi_device *device)
 374 {
 375         ACPI_FUNCTION_TRACE("acpi_processor_remove_fs");
 376
 377         if (acpi_device_dir(device)) {
 378                 remove_proc_entry(ACPI_PROCESSOR_FILE_INFO,
 379                                   acpi_device_dir(device));
 380                 remove_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
 381                                   acpi_device_dir(device));
 382                 remove_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
 383                                   acpi_device_dir(device));
 384                 remove_proc_entry(acpi_device_bid(device), acpi_processor_dir);
 385                 acpi_device_dir(device) = NULL;
 386         }
 387
 388         return_VALUE(0);
 389 }
 390
 391 /* Use the acpiid in MADT to map cpus in case of SMP */
 392 #ifndef CONFIG_SMP
 393 #define convert_acpiid_to_cpu(acpi_id) (0xff)
 394 #else
 395
 396 #ifdef CONFIG_IA64
 397 #define arch_acpiid_to_apicid   ia64_acpiid_to_sapicid
 398 #define arch_cpu_to_apicid      ia64_cpu_to_sapicid
 399 #define ARCH_BAD_APICID         (0xffff)
 400 #else
 401 #define arch_acpiid_to_apicid   x86_acpiid_to_apicid
 402 #define arch_cpu_to_apicid      x86_cpu_to_apicid
 403 #define ARCH_BAD_APICID         (0xff)
 404 #endif
 405
 406 static u8 convert_acpiid_to_cpu(u8 acpi_id)
 407 {
 408         u16 apic_id;
 409         int i;
 410
 411         apic_id = arch_acpiid_to_apicid[acpi_id];
 412         if (apic_id == ARCH_BAD_APICID)
 413                 return -1;
 414
 415         for (i = 0; i < NR_CPUS; i++) {
 416                 if (arch_cpu_to_apicid[i] == apic_id)
 417                         return i;
 418         }
 419         return -1;
 420 }
 421 #endif
 422
 423 /* --------------------------------------------------------------------------
 424                                  Driver Interface
 425    -------------------------------------------------------------------------- */
 426
 427 static int acpi_processor_get_info(struct acpi_processor *pr)
 428 {
 429         acpi_status status = 0;
 430         union acpi_object object = { 0 };
 431         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
 432         u8 cpu_index;
 433         static int cpu0_initialized;
 434
 435         ACPI_FUNCTION_TRACE("acpi_processor_get_info");
 436
 437         if (!pr)
 438                 return_VALUE(-EINVAL);
 439
 440         if (num_online_cpus() > 1)
 441                 errata.smp = TRUE;
 442
 443         acpi_processor_errata(pr);
 444
 445         /*
 446          * Check to see if we have bus mastering arbitration control.  This
 447          * is required for proper C3 usage (to maintain cache coherency).
 448          */
 449         if (acpi_fadt.V1_pm2_cnt_blk && acpi_fadt.pm2_cnt_len) {
 450                 pr->flags.bm_control = 1;
 451                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 452                                   "Bus mastering arbitration control present\n"));
 453         } else
 454                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 455                                   "No bus mastering arbitration control\n"));
 456
 457         /*
 458          * Evalute the processor object.  Note that it is common on SMP to
 459          * have the first (boot) processor with a valid PBLK address while
 460          * all others have a NULL address.
 461          */
 462         status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
 463         if (ACPI_FAILURE(status)) {
 464                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 465                                   "Error evaluating processor object\n"));
 466                 return_VALUE(-ENODEV);
 467         }
 468
 469         /*
 470          * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
 471          *      >>> 'acpi_get_processor_id(acpi_id, &id)' in arch/xxx/acpi.c
 472          */
 473         pr->acpi_id = object.processor.proc_id;
 474
 475         cpu_index = convert_acpiid_to_cpu(pr->acpi_id);
 476
 477         /* Handle UP system running SMP kernel, with no LAPIC in MADT */
 478         if (!cpu0_initialized && (cpu_index == 0xff) &&
 479             (num_online_cpus() == 1)) {
 480                 cpu_index = 0;
 481         }
 482
 483         cpu0_initialized = 1;
 484
 485         pr->id = cpu_index;
 486
 487         /*
 488          *  Extra Processor objects may be enumerated on MP systems with
 489          *  less than the max # of CPUs. They should be ignored _iff
 490          *  they are physically not present.
 491          */
 492         if (cpu_index >= NR_CPUS) {
 493                 if (ACPI_FAILURE
 494                     (acpi_processor_hotadd_init(pr->handle, &pr->id))) {
 495                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 496                                           "Error getting cpuindex for acpiid 0x%x\n",
 497                                           pr->acpi_id));
 498                         return_VALUE(-ENODEV);
 499                 }
 500         }
 501
 502         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
 503                           pr->acpi_id));
 504
 505         if (!object.processor.pblk_address)
 506                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
 507         else if (object.processor.pblk_length != 6)
 508                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid PBLK length [%d]\n",
 509                                   object.processor.pblk_length));
 510         else {
 511                 pr->throttling.address = object.processor.pblk_address;
 512                 pr->throttling.duty_offset = acpi_fadt.duty_offset;
 513                 pr->throttling.duty_width = acpi_fadt.duty_width;
 514
 515                 pr->pblk = object.processor.pblk_address;
 516
 517                 /*
 518                  * We don't care about error returns - we just try to mark
 519                  * these reserved so that nobody else is confused into thinking
 520                  * that this region might be unused..
 521                  *
 522                  * (In particular, allocating the IO range for Cardbus)
 523                  */
 524                 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
 525         }
 526
 527 #ifdef CONFIG_CPU_FREQ
 528         acpi_processor_ppc_has_changed(pr);
 529 #endif
 530         acpi_processor_get_throttling_info(pr);
 531         acpi_processor_get_limit_info(pr);
 532
 533         return_VALUE(0);
 534 }
 535
 536 static int acpi_processor_start(struct acpi_device *device)
 537 {
 538         int result = 0;
 539         acpi_status status = AE_OK;
 540         struct acpi_processor *pr;
 541
 542         ACPI_FUNCTION_TRACE("acpi_processor_start");
 543
 544         pr = acpi_driver_data(device);
 545
 546         result = acpi_processor_get_info(pr);
 547         if (result) {
 548                 /* Processor is physically not present */
 549                 return_VALUE(0);
 550         }
 551
 552         BUG_ON((pr->id >= NR_CPUS) || (pr->id < 0));
 553
 554         processors[pr->id] = pr;
 555
 556         result = acpi_processor_add_fs(device);
 557         if (result)
 558                 goto end;
 559
 560         status = acpi_install_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
 561                                              acpi_processor_notify, pr);
 562         if (ACPI_FAILURE(status)) {
 563                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 564                                   "Error installing device notify handler\n"));
 565         }
 566
 567         /* _PDC call should be done before doing anything else (if reqd.). */
 568         arch_acpi_processor_init_pdc(pr);
 569         acpi_processor_set_pdc(pr);
 570
 571         acpi_processor_power_init(pr, device);
 572
 573         if (pr->flags.throttling) {
 574                 printk(KERN_INFO PREFIX "%s [%s] (supports",
 575                        acpi_device_name(device), acpi_device_bid(device));
 576                 printk(" %d throttling states", pr->throttling.state_count);
 577                 printk(")\n");
 578         }
 579
 580       end:
 581
 582         return_VALUE(result);
 583 }
 584
 585 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
 586 {
 587         struct acpi_processor *pr = (struct acpi_processor *)data;
 588         struct acpi_device *device = NULL;
 589
 590         ACPI_FUNCTION_TRACE("acpi_processor_notify");
 591
 592         if (!pr)
 593                 return_VOID;
 594
 595         if (acpi_bus_get_device(pr->handle, &device))
 596                 return_VOID;
 597
 598         switch (event) {
 599         case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
 600                 acpi_processor_ppc_has_changed(pr);
 601                 acpi_bus_generate_event(device, event,
 602                                         pr->performance_platform_limit);
 603                 break;
 604         case ACPI_PROCESSOR_NOTIFY_POWER:
 605                 acpi_processor_cst_has_changed(pr);
 606                 acpi_bus_generate_event(device, event, 0);
 607                 break;
 608         default:
 609                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 610                                   "Unsupported event [0x%x]\n", event));
 611                 break;
 612         }
 613
 614         return_VOID;
 615 }
 616
 617 static int acpi_processor_add(struct acpi_device *device)
 618 {
 619         struct acpi_processor *pr = NULL;
 620
 621         ACPI_FUNCTION_TRACE("acpi_processor_add");
 622
 623         if (!device)
 624                 return_VALUE(-EINVAL);
 625
 626         pr = kmalloc(sizeof(struct acpi_processor), GFP_KERNEL);
 627         if (!pr)
 628                 return_VALUE(-ENOMEM);
 629         memset(pr, 0, sizeof(struct acpi_processor));
 630
 631         pr->handle = device->handle;
 632         strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 633         strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
 634         acpi_driver_data(device) = pr;
 635
 636         return_VALUE(0);
 637 }
 638
 639 static int acpi_processor_remove(struct acpi_device *device, int type)
 640 {
 641         acpi_status status = AE_OK;
 642         struct acpi_processor *pr = NULL;
 643
 644         ACPI_FUNCTION_TRACE("acpi_processor_remove");
 645
 646         if (!device || !acpi_driver_data(device))
 647                 return_VALUE(-EINVAL);
 648
 649         pr = (struct acpi_processor *)acpi_driver_data(device);
 650
 651         if (pr->id >= NR_CPUS) {
 652                 kfree(pr);
 653                 return_VALUE(0);
 654         }
 655
 656         if (type == ACPI_BUS_REMOVAL_EJECT) {
 657                 if (acpi_processor_handle_eject(pr))
 658                         return_VALUE(-EINVAL);
 659         }
 660
 661         acpi_processor_power_exit(pr, device);
 662
 663         status = acpi_remove_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
 664                                             acpi_processor_notify);
 665         if (ACPI_FAILURE(status)) {
 666                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 667                                   "Error removing notify handler\n"));
 668         }
 669
 670         acpi_processor_remove_fs(device);
 671
 672         processors[pr->id] = NULL;
 673
 674         kfree(pr);
 675
 676         return_VALUE(0);
 677 }
 678
 679 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 680 /****************************************************************************
 681  *      Acpi processor hotplug support                                      *
 682  ****************************************************************************/
 683
 684 static int is_processor_present(acpi_handle handle);
 685
 686 static int is_processor_present(acpi_handle handle)
 687 {
 688         acpi_status status;
 689         unsigned long sta = 0;
 690
 691         ACPI_FUNCTION_TRACE("is_processor_present");
 692
 693         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
 694         if (ACPI_FAILURE(status) || !(sta & ACPI_STA_PRESENT)) {
 695                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 696                                   "Processor Device is not present\n"));
 697                 return_VALUE(0);
 698         }
 699         return_VALUE(1);
 700 }
 701
 702 static
 703 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
 704 {
 705         acpi_handle phandle;
 706         struct acpi_device *pdev;
 707         struct acpi_processor *pr;
 708
 709         ACPI_FUNCTION_TRACE("acpi_processor_device_add");
 710
 711         if (acpi_get_parent(handle, &phandle)) {
 712                 return_VALUE(-ENODEV);
 713         }
 714
 715         if (acpi_bus_get_device(phandle, &pdev)) {
 716                 return_VALUE(-ENODEV);
 717         }
 718
 719         if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
 720                 return_VALUE(-ENODEV);
 721         }
 722
 723         acpi_bus_start(*device);
 724
 725         pr = acpi_driver_data(*device);
 726         if (!pr)
 727                 return_VALUE(-ENODEV);
 728
 729         if ((pr->id >= 0) && (pr->id < NR_CPUS)) {
 730                 kobject_hotplug(&(*device)->kobj, KOBJ_ONLINE);
 731         }
 732         return_VALUE(0);
 733 }
 734
 735 static void
 736 acpi_processor_hotplug_notify(acpi_handle handle, u32 event, void *data)
 737 {
 738         struct acpi_processor *pr;
 739         struct acpi_device *device = NULL;
 740         int result;
 741
 742         ACPI_FUNCTION_TRACE("acpi_processor_hotplug_notify");
 743
 744         switch (event) {
 745         case ACPI_NOTIFY_BUS_CHECK:
 746         case ACPI_NOTIFY_DEVICE_CHECK:
 747                 printk("Processor driver received %s event\n",
 748                        (event == ACPI_NOTIFY_BUS_CHECK) ?
 749                        "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");
 750
 751                 if (!is_processor_present(handle))
 752                         break;
 753
 754                 if (acpi_bus_get_device(handle, &device)) {
 755                         result = acpi_processor_device_add(handle, &device);
 756                         if (result)
 757                                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 758                                                   "Unable to add the device\n"));
 759                         break;
 760                 }
 761
 762                 pr = acpi_driver_data(device);
 763                 if (!pr) {
 764                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 765                                           "Driver data is NULL\n"));
 766                         break;
 767                 }
 768
 769                 if (pr->id >= 0 && (pr->id < NR_CPUS)) {
 770                         kobject_hotplug(&device->kobj, KOBJ_OFFLINE);
 771                         break;
 772                 }
 773
 774                 result = acpi_processor_start(device);
 775                 if ((!result) && ((pr->id >= 0) && (pr->id < NR_CPUS))) {
 776                         kobject_hotplug(&device->kobj, KOBJ_ONLINE);
 777                 } else {
 778                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 779                                           "Device [%s] failed to start\n",
 780                                           acpi_device_bid(device)));
 781                 }
 782                 break;
 783         case ACPI_NOTIFY_EJECT_REQUEST:
 784                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 785                                   "received ACPI_NOTIFY_EJECT_REQUEST\n"));
 786
 787                 if (acpi_bus_get_device(handle, &device)) {
 788                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 789                                           "Device don't exist, dropping EJECT\n"));
 790                         break;
 791                 }
 792                 pr = acpi_driver_data(device);
 793                 if (!pr) {
 794                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 795                                           "Driver data is NULL, dropping EJECT\n"));
 796                         return_VOID;
 797                 }
 798
 799                 if ((pr->id < NR_CPUS) && (cpu_present(pr->id)))
 800                         kobject_hotplug(&device->kobj, KOBJ_OFFLINE);
 801                 break;
 802         default:
 803                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 804                                   "Unsupported event [0x%x]\n", event));
 805                 break;
 806         }
 807
 808         return_VOID;
 809 }
 810
 811 static acpi_status
 812 processor_walk_namespace_cb(acpi_handle handle,
 813                             u32 lvl, void *context, void **rv)
 814 {
 815         acpi_status status;
 816         int *action = context;
 817         acpi_object_type type = 0;
 818
 819         status = acpi_get_type(handle, &type);
 820         if (ACPI_FAILURE(status))
 821                 return (AE_OK);
 822
 823         if (type != ACPI_TYPE_PROCESSOR)
 824                 return (AE_OK);
 825
 826         switch (*action) {
 827         case INSTALL_NOTIFY_HANDLER:
 828                 acpi_install_notify_handler(handle,
 829                                             ACPI_SYSTEM_NOTIFY,
 830                                             acpi_processor_hotplug_notify,
 831                                             NULL);
 832                 break;
 833         case UNINSTALL_NOTIFY_HANDLER:
 834                 acpi_remove_notify_handler(handle,
 835                                            ACPI_SYSTEM_NOTIFY,
 836                                            acpi_processor_hotplug_notify);
 837                 break;
 838         default:
 839                 break;
 840         }
 841
 842         return (AE_OK);
 843 }
 844
 845 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
 846 {
 847         ACPI_FUNCTION_TRACE("acpi_processor_hotadd_init");
 848
 849         if (!is_processor_present(handle)) {
 850                 return_VALUE(AE_ERROR);
 851         }
 852
 853         if (acpi_map_lsapic(handle, p_cpu))
 854                 return_VALUE(AE_ERROR);
 855
 856         if (arch_register_cpu(*p_cpu)) {
 857                 acpi_unmap_lsapic(*p_cpu);
 858                 return_VALUE(AE_ERROR);
 859         }
 860
 861         return_VALUE(AE_OK);
 862 }
 863
 864 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 865 {
 866         if (cpu_online(pr->id)) {
 867                 return (-EINVAL);
 868         }
 869         arch_unregister_cpu(pr->id);
 870         acpi_unmap_lsapic(pr->id);
 871         return (0);
 872 }
 873 #else
 874 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
 875 {
 876         return AE_ERROR;
 877 }
 878 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 879 {
 880         return (-EINVAL);
 881 }
 882 #endif
 883
 884 static
 885 void acpi_processor_install_hotplug_notify(void)
 886 {
 887 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 888         int action = INSTALL_NOTIFY_HANDLER;
 889         acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
 890                             ACPI_ROOT_OBJECT,
 891                             ACPI_UINT32_MAX,
 892                             processor_walk_namespace_cb, &action, NULL);
 893 #endif
 894 }
 895
 896 static
 897 void acpi_processor_uninstall_hotplug_notify(void)
 898 {
 899 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 900         int action = UNINSTALL_NOTIFY_HANDLER;
 901         acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
 902                             ACPI_ROOT_OBJECT,
 903                             ACPI_UINT32_MAX,
 904                             processor_walk_namespace_cb, &action, NULL);
 905 #endif
 906 }
 907
 908 /*
 909  * We keep the driver loaded even when ACPI is not running.
 910  * This is needed for the powernow-k8 driver, that works even without
 911  * ACPI, but needs symbols from this driver
 912  */
 913
 914 static int __init acpi_processor_init(void)
 915 {
 916         int result = 0;
 917
 918         ACPI_FUNCTION_TRACE("acpi_processor_init");
 919
 920         memset(&processors, 0, sizeof(processors));
 921         memset(&errata, 0, sizeof(errata));
 922
 923         acpi_processor_dir = proc_mkdir(ACPI_PROCESSOR_CLASS, acpi_root_dir);
 924         if (!acpi_processor_dir)
 925                 return_VALUE(0);
 926         acpi_processor_dir->owner = THIS_MODULE;
 927
 928         result = acpi_bus_register_driver(&acpi_processor_driver);
 929         if (result < 0) {
 930                 remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
 931                 return_VALUE(0);
 932         }
 933
 934         acpi_processor_install_hotplug_notify();
 935
 936         acpi_thermal_cpufreq_init();
 937
 938         acpi_processor_ppc_init();
 939
 940         return_VALUE(0);
 941 }
 942
 943 static void __exit acpi_processor_exit(void)
 944 {
 945         ACPI_FUNCTION_TRACE("acpi_processor_exit");
 946
 947         acpi_processor_ppc_exit();
 948
 949         acpi_thermal_cpufreq_exit();
 950
 951         acpi_processor_uninstall_hotplug_notify();
 952
 953         acpi_bus_unregister_driver(&acpi_processor_driver);
 954
 955         remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
 956
 957         return_VOID;
 958 }
 959
 960 module_init(acpi_processor_init);
 961 module_exit(acpi_processor_exit);
 962
 963 EXPORT_SYMBOL(acpi_processor_set_thermal_limit);
 964
 965 MODULE_ALIAS("processor");