1 /* 2 * acpi_processor.c - ACPI Processor Driver ($Revision: 71 $) 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> 7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 8 * - Added processor hotplug support 9 * 10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2 of the License, or (at 15 * your option) any later version. 16 * 17 * This program is distributed in the hope that it will be useful, but 18 * WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 * General Public License for more details. 21 * 22 * You should have received a copy of the GNU General Public License along 23 * with this program; if not, write to the Free Software Foundation, Inc., 24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 25 * 26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 27 * TBD: 28 * 1. Make # power states dynamic. 29 * 2. Support duty_cycle values that span bit 4. 30 * 3. Optimize by having scheduler determine business instead of 31 * having us try to calculate it here. 32 * 4. Need C1 timing -- must modify kernel (IRQ handler) to get this. 33 */ 34 35 #include <linux/kernel.h> 36 #include <linux/module.h> 37 #include <linux/init.h> 38 #include <linux/types.h> 39 #include <linux/pci.h> 40 #include <linux/pm.h> 41 #include <linux/cpufreq.h> 42 #include <linux/cpu.h> 43 #include <linux/dmi.h> 44 #include <linux/moduleparam.h> 45 #include <linux/cpuidle.h> 46 #include <linux/slab.h> 47 48 #include <asm/io.h> 49 #include <asm/system.h> 50 #include <asm/cpu.h> 51 #include <asm/delay.h> 52 #include <asm/uaccess.h> 53 #include <asm/processor.h> 54 #include <asm/smp.h> 55 #include <asm/acpi.h> 56 57 #include <acpi/acpi_bus.h> 58 #include <acpi/acpi_drivers.h> 59 #include <acpi/processor.h> 60 61 #define PREFIX "ACPI: " 62 63 #define ACPI_PROCESSOR_CLASS "processor" 64 #define ACPI_PROCESSOR_DEVICE_NAME "Processor" 65 #define ACPI_PROCESSOR_FILE_INFO "info" 66 #define ACPI_PROCESSOR_FILE_THROTTLING "throttling" 67 #define ACPI_PROCESSOR_FILE_LIMIT "limit" 68 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80 69 #define ACPI_PROCESSOR_NOTIFY_POWER 0x81 70 #define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82 71 72 #define ACPI_PROCESSOR_LIMIT_USER 0 73 #define ACPI_PROCESSOR_LIMIT_THERMAL 1 74 75 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 76 ACPI_MODULE_NAME("processor_driver"); 77 78 MODULE_AUTHOR("Paul Diefenbaugh"); 79 MODULE_DESCRIPTION("ACPI Processor Driver"); 80 MODULE_LICENSE("GPL"); 81 82 static int acpi_processor_add(struct acpi_device *device); 83 static int acpi_processor_remove(struct acpi_device *device, int type); 84 static void acpi_processor_notify(struct acpi_device *device, u32 event); 85 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr); 86 static int acpi_processor_handle_eject(struct acpi_processor *pr); 87 static int acpi_processor_start(struct acpi_processor *pr); 88 89 static const struct acpi_device_id processor_device_ids[] = { 90 {ACPI_PROCESSOR_OBJECT_HID, 0}, 91 {"ACPI0007", 0}, 92 {"", 0}, 93 }; 94 MODULE_DEVICE_TABLE(acpi, processor_device_ids); 95 96 static struct acpi_driver acpi_processor_driver = { 97 .name = "processor", 98 .class = ACPI_PROCESSOR_CLASS, 99 .ids = processor_device_ids, 100 .ops = { 101 .add = acpi_processor_add, 102 .remove = acpi_processor_remove, 103 .suspend = acpi_processor_suspend, 104 .resume = acpi_processor_resume, 105 .notify = acpi_processor_notify, 106 }, 107 }; 108 109 #define INSTALL_NOTIFY_HANDLER 1 110 #define UNINSTALL_NOTIFY_HANDLER 2 111 112 DEFINE_PER_CPU(struct acpi_processor *, processors); 113 EXPORT_PER_CPU_SYMBOL(processors); 114 115 struct acpi_processor_errata errata __read_mostly; 116 117 /* -------------------------------------------------------------------------- 118 Errata Handling 119 -------------------------------------------------------------------------- */ 120 121 static int acpi_processor_errata_piix4(struct pci_dev *dev) 122 { 123 u8 value1 = 0; 124 u8 value2 = 0; 125 126 127 if (!dev) 128 return -EINVAL; 129 130 /* 131 * Note that 'dev' references the PIIX4 ACPI Controller. 132 */ 133 134 switch (dev->revision) { 135 case 0: 136 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n")); 137 break; 138 case 1: 139 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n")); 140 break; 141 case 2: 142 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n")); 143 break; 144 case 3: 145 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n")); 146 break; 147 default: 148 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n")); 149 break; 150 } 151 152 switch (dev->revision) { 153 154 case 0: /* PIIX4 A-step */ 155 case 1: /* PIIX4 B-step */ 156 /* 157 * See specification changes #13 ("Manual Throttle Duty Cycle") 158 * and #14 ("Enabling and Disabling Manual Throttle"), plus 159 * erratum #5 ("STPCLK# Deassertion Time") from the January 160 * 2002 PIIX4 specification update. Applies to only older 161 * PIIX4 models. 162 */ 163 errata.piix4.throttle = 1; 164 165 case 2: /* PIIX4E */ 166 case 3: /* PIIX4M */ 167 /* 168 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA 169 * Livelock") from the January 2002 PIIX4 specification update. 170 * Applies to all PIIX4 models. 171 */ 172 173 /* 174 * BM-IDE 175 * ------ 176 * Find the PIIX4 IDE Controller and get the Bus Master IDE 177 * Status register address. We'll use this later to read 178 * each IDE controller's DMA status to make sure we catch all 179 * DMA activity. 180 */ 181 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 182 PCI_DEVICE_ID_INTEL_82371AB, 183 PCI_ANY_ID, PCI_ANY_ID, NULL); 184 if (dev) { 185 errata.piix4.bmisx = pci_resource_start(dev, 4); 186 pci_dev_put(dev); 187 } 188 189 /* 190 * Type-F DMA 191 * ---------- 192 * Find the PIIX4 ISA Controller and read the Motherboard 193 * DMA controller's status to see if Type-F (Fast) DMA mode 194 * is enabled (bit 7) on either channel. Note that we'll 195 * disable C3 support if this is enabled, as some legacy 196 * devices won't operate well if fast DMA is disabled. 197 */ 198 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 199 PCI_DEVICE_ID_INTEL_82371AB_0, 200 PCI_ANY_ID, PCI_ANY_ID, NULL); 201 if (dev) { 202 pci_read_config_byte(dev, 0x76, &value1); 203 pci_read_config_byte(dev, 0x77, &value2); 204 if ((value1 & 0x80) || (value2 & 0x80)) 205 errata.piix4.fdma = 1; 206 pci_dev_put(dev); 207 } 208 209 break; 210 } 211 212 if (errata.piix4.bmisx) 213 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 214 "Bus master activity detection (BM-IDE) erratum enabled\n")); 215 if (errata.piix4.fdma) 216 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 217 "Type-F DMA livelock erratum (C3 disabled)\n")); 218 219 return 0; 220 } 221 222 static int acpi_processor_errata(struct acpi_processor *pr) 223 { 224 int result = 0; 225 struct pci_dev *dev = NULL; 226 227 228 if (!pr) 229 return -EINVAL; 230 231 /* 232 * PIIX4 233 */ 234 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 235 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID, 236 PCI_ANY_ID, NULL); 237 if (dev) { 238 result = acpi_processor_errata_piix4(dev); 239 pci_dev_put(dev); 240 } 241 242 return result; 243 } 244 245 /* -------------------------------------------------------------------------- 246 Driver Interface 247 -------------------------------------------------------------------------- */ 248 249 static int acpi_processor_get_info(struct acpi_device *device) 250 { 251 acpi_status status = 0; 252 union acpi_object object = { 0 }; 253 struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; 254 struct acpi_processor *pr; 255 int cpu_index, device_declaration = 0; 256 static int cpu0_initialized; 257 258 pr = acpi_driver_data(device); 259 if (!pr) 260 return -EINVAL; 261 262 if (num_online_cpus() > 1) 263 errata.smp = TRUE; 264 265 acpi_processor_errata(pr); 266 267 /* 268 * Check to see if we have bus mastering arbitration control. This 269 * is required for proper C3 usage (to maintain cache coherency). 270 */ 271 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) { 272 pr->flags.bm_control = 1; 273 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 274 "Bus mastering arbitration control present\n")); 275 } else 276 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 277 "No bus mastering arbitration control\n")); 278 279 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) { 280 /* Declared with "Processor" statement; match ProcessorID */ 281 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer); 282 if (ACPI_FAILURE(status)) { 283 printk(KERN_ERR PREFIX "Evaluating processor object\n"); 284 return -ENODEV; 285 } 286 287 /* 288 * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP. 289 * >>> 'acpi_get_processor_id(acpi_id, &id)' in 290 * arch/xxx/acpi.c 291 */ 292 pr->acpi_id = object.processor.proc_id; 293 } else { 294 /* 295 * Declared with "Device" statement; match _UID. 296 * Note that we don't handle string _UIDs yet. 297 */ 298 unsigned long long value; 299 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID, 300 NULL, &value); 301 if (ACPI_FAILURE(status)) { 302 printk(KERN_ERR PREFIX 303 "Evaluating processor _UID [%#x]\n", status); 304 return -ENODEV; 305 } 306 device_declaration = 1; 307 pr->acpi_id = value; 308 } 309 cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id); 310 311 /* Handle UP system running SMP kernel, with no LAPIC in MADT */ 312 if (!cpu0_initialized && (cpu_index == -1) && 313 (num_online_cpus() == 1)) { 314 cpu_index = 0; 315 } 316 317 cpu0_initialized = 1; 318 319 pr->id = cpu_index; 320 321 /* 322 * Extra Processor objects may be enumerated on MP systems with 323 * less than the max # of CPUs. They should be ignored _iff 324 * they are physically not present. 325 */ 326 if (pr->id == -1) { 327 if (ACPI_FAILURE(acpi_processor_hotadd_init(pr))) 328 return -ENODEV; 329 } 330 /* 331 * On some boxes several processors use the same processor bus id. 332 * But they are located in different scope. For example: 333 * \_SB.SCK0.CPU0 334 * \_SB.SCK1.CPU0 335 * Rename the processor device bus id. And the new bus id will be 336 * generated as the following format: 337 * CPU+CPU ID. 338 */ 339 sprintf(acpi_device_bid(device), "CPU%X", pr->id); 340 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id, 341 pr->acpi_id)); 342 343 if (!object.processor.pblk_address) 344 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n")); 345 else if (object.processor.pblk_length != 6) 346 printk(KERN_ERR PREFIX "Invalid PBLK length [%d]\n", 347 object.processor.pblk_length); 348 else { 349 pr->throttling.address = object.processor.pblk_address; 350 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset; 351 pr->throttling.duty_width = acpi_gbl_FADT.duty_width; 352 353 pr->pblk = object.processor.pblk_address; 354 355 /* 356 * We don't care about error returns - we just try to mark 357 * these reserved so that nobody else is confused into thinking 358 * that this region might be unused.. 359 * 360 * (In particular, allocating the IO range for Cardbus) 361 */ 362 request_region(pr->throttling.address, 6, "ACPI CPU throttle"); 363 } 364 365 /* 366 * If ACPI describes a slot number for this CPU, we can use it 367 * ensure we get the right value in the "physical id" field 368 * of /proc/cpuinfo 369 */ 370 status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer); 371 if (ACPI_SUCCESS(status)) 372 arch_fix_phys_package_id(pr->id, object.integer.value); 373 374 return 0; 375 } 376 377 static DEFINE_PER_CPU(void *, processor_device_array); 378 379 static void acpi_processor_notify(struct acpi_device *device, u32 event) 380 { 381 struct acpi_processor *pr = acpi_driver_data(device); 382 int saved; 383 384 if (!pr) 385 return; 386 387 switch (event) { 388 case ACPI_PROCESSOR_NOTIFY_PERFORMANCE: 389 saved = pr->performance_platform_limit; 390 acpi_processor_ppc_has_changed(pr, 1); 391 if (saved == pr->performance_platform_limit) 392 break; 393 acpi_bus_generate_proc_event(device, event, 394 pr->performance_platform_limit); 395 acpi_bus_generate_netlink_event(device->pnp.device_class, 396 dev_name(&device->dev), event, 397 pr->performance_platform_limit); 398 break; 399 case ACPI_PROCESSOR_NOTIFY_POWER: 400 acpi_processor_cst_has_changed(pr); 401 acpi_bus_generate_proc_event(device, event, 0); 402 acpi_bus_generate_netlink_event(device->pnp.device_class, 403 dev_name(&device->dev), event, 0); 404 break; 405 case ACPI_PROCESSOR_NOTIFY_THROTTLING: 406 acpi_processor_tstate_has_changed(pr); 407 acpi_bus_generate_proc_event(device, event, 0); 408 acpi_bus_generate_netlink_event(device->pnp.device_class, 409 dev_name(&device->dev), event, 0); 410 default: 411 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 412 "Unsupported event [0x%x]\n", event)); 413 break; 414 } 415 416 return; 417 } 418 419 static int acpi_cpu_soft_notify(struct notifier_block *nfb, 420 unsigned long action, void *hcpu) 421 { 422 unsigned int cpu = (unsigned long)hcpu; 423 struct acpi_processor *pr = per_cpu(processors, cpu); 424 425 if (action == CPU_ONLINE && pr) { 426 /* CPU got physically hotplugged and onlined the first time: 427 * Initialize missing things 428 */ 429 if (pr->flags.need_hotplug_init) { 430 struct cpuidle_driver *idle_driver = 431 cpuidle_get_driver(); 432 433 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 if (idle_driver && !strcmp(idle_driver->name, 439 "intel_idle")) { 440 intel_idle_cpu_init(pr->id); 441 } 442 /* Normal CPU soft online event */ 443 } else { 444 acpi_processor_ppc_has_changed(pr, 0); 445 acpi_processor_cst_has_changed(pr); 446 acpi_processor_reevaluate_tstate(pr, action); 447 acpi_processor_tstate_has_changed(pr); 448 } 449 } 450 if (action == CPU_DEAD && pr) { 451 /* invalidate the flag.throttling after one CPU is offline */ 452 acpi_processor_reevaluate_tstate(pr, action); 453 } 454 return NOTIFY_OK; 455 } 456 457 static struct notifier_block acpi_cpu_notifier = 458 { 459 .notifier_call = acpi_cpu_soft_notify, 460 }; 461 462 /* 463 * acpi_processor_start() is called by the cpu_hotplug_notifier func: 464 * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the 465 * root cause seem to be that acpi_processor_uninstall_hotplug_notify() 466 * is in the module_exit (__exit) func. Allowing acpi_processor_start() 467 * to not be in __cpuinit section, but being called from __cpuinit funcs 468 * via __ref looks like the right thing to do here. 469 */ 470 static __ref int acpi_processor_start(struct acpi_processor *pr) 471 { 472 struct acpi_device *device = per_cpu(processor_device_array, pr->id); 473 int result = 0; 474 475 #ifdef CONFIG_CPU_FREQ 476 acpi_processor_ppc_has_changed(pr, 0); 477 acpi_processor_load_module(pr); 478 #endif 479 acpi_processor_get_throttling_info(pr); 480 acpi_processor_get_limit_info(pr); 481 482 if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver) 483 acpi_processor_power_init(pr, device); 484 485 pr->cdev = thermal_cooling_device_register("Processor", device, 486 &processor_cooling_ops); 487 if (IS_ERR(pr->cdev)) { 488 result = PTR_ERR(pr->cdev); 489 goto err_power_exit; 490 } 491 492 dev_dbg(&device->dev, "registered as cooling_device%d\n", 493 pr->cdev->id); 494 495 result = sysfs_create_link(&device->dev.kobj, 496 &pr->cdev->device.kobj, 497 "thermal_cooling"); 498 if (result) { 499 printk(KERN_ERR PREFIX "Create sysfs link\n"); 500 goto err_thermal_unregister; 501 } 502 result = sysfs_create_link(&pr->cdev->device.kobj, 503 &device->dev.kobj, 504 "device"); 505 if (result) { 506 printk(KERN_ERR PREFIX "Create sysfs link\n"); 507 goto err_remove_sysfs_thermal; 508 } 509 510 return 0; 511 512 err_remove_sysfs_thermal: 513 sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); 514 err_thermal_unregister: 515 thermal_cooling_device_unregister(pr->cdev); 516 err_power_exit: 517 acpi_processor_power_exit(pr, device); 518 519 return result; 520 } 521 522 /* 523 * Do not put anything in here which needs the core to be online. 524 * For example MSR access or setting up things which check for cpuinfo_x86 525 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc. 526 * Such things have to be put in and set up above in acpi_processor_start() 527 */ 528 static int __cpuinit acpi_processor_add(struct acpi_device *device) 529 { 530 struct acpi_processor *pr = NULL; 531 int result = 0; 532 struct device *dev; 533 534 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); 535 if (!pr) 536 return -ENOMEM; 537 538 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) { 539 kfree(pr); 540 return -ENOMEM; 541 } 542 543 pr->handle = device->handle; 544 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); 545 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); 546 device->driver_data = pr; 547 548 result = acpi_processor_get_info(device); 549 if (result) { 550 /* Processor is physically not present */ 551 return 0; 552 } 553 554 #ifdef CONFIG_SMP 555 if (pr->id >= setup_max_cpus && pr->id != 0) 556 return 0; 557 #endif 558 559 BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0)); 560 561 /* 562 * Buggy BIOS check 563 * ACPI id of processors can be reported wrongly by the BIOS. 564 * Don't trust it blindly 565 */ 566 if (per_cpu(processor_device_array, pr->id) != NULL && 567 per_cpu(processor_device_array, pr->id) != device) { 568 printk(KERN_WARNING "BIOS reported wrong ACPI id " 569 "for the processor\n"); 570 result = -ENODEV; 571 goto err_free_cpumask; 572 } 573 per_cpu(processor_device_array, pr->id) = device; 574 575 per_cpu(processors, pr->id) = pr; 576 577 dev = get_cpu_device(pr->id); 578 if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) { 579 result = -EFAULT; 580 goto err_free_cpumask; 581 } 582 583 /* 584 * Do not start hotplugged CPUs now, but when they 585 * are onlined the first time 586 */ 587 if (pr->flags.need_hotplug_init) 588 return 0; 589 590 result = acpi_processor_start(pr); 591 if (result) 592 goto err_remove_sysfs; 593 594 return 0; 595 596 err_remove_sysfs: 597 sysfs_remove_link(&device->dev.kobj, "sysdev"); 598 err_free_cpumask: 599 free_cpumask_var(pr->throttling.shared_cpu_map); 600 601 return result; 602 } 603 604 static int acpi_processor_remove(struct acpi_device *device, int type) 605 { 606 struct acpi_processor *pr = NULL; 607 608 609 if (!device || !acpi_driver_data(device)) 610 return -EINVAL; 611 612 pr = acpi_driver_data(device); 613 614 if (pr->id >= nr_cpu_ids) 615 goto free; 616 617 if (type == ACPI_BUS_REMOVAL_EJECT) { 618 if (acpi_processor_handle_eject(pr)) 619 return -EINVAL; 620 } 621 622 acpi_processor_power_exit(pr, device); 623 624 sysfs_remove_link(&device->dev.kobj, "sysdev"); 625 626 if (pr->cdev) { 627 sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); 628 sysfs_remove_link(&pr->cdev->device.kobj, "device"); 629 thermal_cooling_device_unregister(pr->cdev); 630 pr->cdev = NULL; 631 } 632 633 per_cpu(processors, pr->id) = NULL; 634 per_cpu(processor_device_array, pr->id) = NULL; 635 636 free: 637 free_cpumask_var(pr->throttling.shared_cpu_map); 638 kfree(pr); 639 640 return 0; 641 } 642 643 #ifdef CONFIG_ACPI_HOTPLUG_CPU 644 /**************************************************************************** 645 * Acpi processor hotplug support * 646 ****************************************************************************/ 647 648 static int is_processor_present(acpi_handle handle) 649 { 650 acpi_status status; 651 unsigned long long sta = 0; 652 653 654 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); 655 656 if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT)) 657 return 1; 658 659 /* 660 * _STA is mandatory for a processor that supports hot plug 661 */ 662 if (status == AE_NOT_FOUND) 663 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 664 "Processor does not support hot plug\n")); 665 else 666 ACPI_EXCEPTION((AE_INFO, status, 667 "Processor Device is not present")); 668 return 0; 669 } 670 671 static 672 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device) 673 { 674 acpi_handle phandle; 675 struct acpi_device *pdev; 676 677 678 if (acpi_get_parent(handle, &phandle)) { 679 return -ENODEV; 680 } 681 682 if (acpi_bus_get_device(phandle, &pdev)) { 683 return -ENODEV; 684 } 685 686 if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) { 687 return -ENODEV; 688 } 689 690 return 0; 691 } 692 693 static void acpi_processor_hotplug_notify(acpi_handle handle, 694 u32 event, void *data) 695 { 696 struct acpi_processor *pr; 697 struct acpi_device *device = NULL; 698 int result; 699 700 701 switch (event) { 702 case ACPI_NOTIFY_BUS_CHECK: 703 case ACPI_NOTIFY_DEVICE_CHECK: 704 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 705 "Processor driver received %s event\n", 706 (event == ACPI_NOTIFY_BUS_CHECK) ? 707 "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK")); 708 709 if (!is_processor_present(handle)) 710 break; 711 712 if (acpi_bus_get_device(handle, &device)) { 713 result = acpi_processor_device_add(handle, &device); 714 if (result) 715 printk(KERN_ERR PREFIX 716 "Unable to add the device\n"); 717 break; 718 } 719 break; 720 case ACPI_NOTIFY_EJECT_REQUEST: 721 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 722 "received ACPI_NOTIFY_EJECT_REQUEST\n")); 723 724 if (acpi_bus_get_device(handle, &device)) { 725 printk(KERN_ERR PREFIX 726 "Device don't exist, dropping EJECT\n"); 727 break; 728 } 729 pr = acpi_driver_data(device); 730 if (!pr) { 731 printk(KERN_ERR PREFIX 732 "Driver data is NULL, dropping EJECT\n"); 733 return; 734 } 735 break; 736 default: 737 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 738 "Unsupported event [0x%x]\n", event)); 739 break; 740 } 741 742 return; 743 } 744 745 static acpi_status 746 processor_walk_namespace_cb(acpi_handle handle, 747 u32 lvl, void *context, void **rv) 748 { 749 acpi_status status; 750 int *action = context; 751 acpi_object_type type = 0; 752 753 status = acpi_get_type(handle, &type); 754 if (ACPI_FAILURE(status)) 755 return (AE_OK); 756 757 if (type != ACPI_TYPE_PROCESSOR) 758 return (AE_OK); 759 760 switch (*action) { 761 case INSTALL_NOTIFY_HANDLER: 762 acpi_install_notify_handler(handle, 763 ACPI_SYSTEM_NOTIFY, 764 acpi_processor_hotplug_notify, 765 NULL); 766 break; 767 case UNINSTALL_NOTIFY_HANDLER: 768 acpi_remove_notify_handler(handle, 769 ACPI_SYSTEM_NOTIFY, 770 acpi_processor_hotplug_notify); 771 break; 772 default: 773 break; 774 } 775 776 return (AE_OK); 777 } 778 779 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) 780 { 781 acpi_handle handle = pr->handle; 782 783 if (!is_processor_present(handle)) { 784 return AE_ERROR; 785 } 786 787 if (acpi_map_lsapic(handle, &pr->id)) 788 return AE_ERROR; 789 790 if (arch_register_cpu(pr->id)) { 791 acpi_unmap_lsapic(pr->id); 792 return AE_ERROR; 793 } 794 795 /* CPU got hot-plugged, but cpu_data is not initialized yet 796 * Set flag to delay cpu_idle/throttling initialization 797 * in: 798 * acpi_processor_add() 799 * acpi_processor_get_info() 800 * and do it when the CPU gets online the first time 801 * TBD: Cleanup above functions and try to do this more elegant. 802 */ 803 printk(KERN_INFO "CPU %d got hotplugged\n", pr->id); 804 pr->flags.need_hotplug_init = 1; 805 806 return AE_OK; 807 } 808 809 static int acpi_processor_handle_eject(struct acpi_processor *pr) 810 { 811 if (cpu_online(pr->id)) 812 cpu_down(pr->id); 813 814 arch_unregister_cpu(pr->id); 815 acpi_unmap_lsapic(pr->id); 816 return (0); 817 } 818 #else 819 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) 820 { 821 return AE_ERROR; 822 } 823 static int acpi_processor_handle_eject(struct acpi_processor *pr) 824 { 825 return (-EINVAL); 826 } 827 #endif 828 829 static 830 void acpi_processor_install_hotplug_notify(void) 831 { 832 #ifdef CONFIG_ACPI_HOTPLUG_CPU 833 int action = INSTALL_NOTIFY_HANDLER; 834 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, 835 ACPI_ROOT_OBJECT, 836 ACPI_UINT32_MAX, 837 processor_walk_namespace_cb, NULL, &action, NULL); 838 #endif 839 register_hotcpu_notifier(&acpi_cpu_notifier); 840 } 841 842 static 843 void acpi_processor_uninstall_hotplug_notify(void) 844 { 845 #ifdef CONFIG_ACPI_HOTPLUG_CPU 846 int action = UNINSTALL_NOTIFY_HANDLER; 847 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, 848 ACPI_ROOT_OBJECT, 849 ACPI_UINT32_MAX, 850 processor_walk_namespace_cb, NULL, &action, NULL); 851 #endif 852 unregister_hotcpu_notifier(&acpi_cpu_notifier); 853 } 854 855 /* 856 * We keep the driver loaded even when ACPI is not running. 857 * This is needed for the powernow-k8 driver, that works even without 858 * ACPI, but needs symbols from this driver 859 */ 860 861 static int __init acpi_processor_init(void) 862 { 863 int result = 0; 864 865 if (acpi_disabled) 866 return 0; 867 868 memset(&errata, 0, sizeof(errata)); 869 870 result = acpi_bus_register_driver(&acpi_processor_driver); 871 if (result < 0) 872 return result; 873 874 acpi_processor_install_hotplug_notify(); 875 876 acpi_thermal_cpufreq_init(); 877 878 acpi_processor_ppc_init(); 879 880 acpi_processor_throttling_init(); 881 882 return 0; 883 } 884 885 static void __exit acpi_processor_exit(void) 886 { 887 if (acpi_disabled) 888 return; 889 890 acpi_processor_ppc_exit(); 891 892 acpi_thermal_cpufreq_exit(); 893 894 acpi_processor_uninstall_hotplug_notify(); 895 896 acpi_bus_unregister_driver(&acpi_processor_driver); 897 898 return; 899 } 900 901 module_init(acpi_processor_init); 902 module_exit(acpi_processor_exit); 903 904 MODULE_ALIAS("processor"); 905