1 /* 2 * acpi_processor.c - ACPI Processor Driver ($Revision: 71 $) 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> 7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 8 * - Added processor hotplug support 9 * 10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2 of the License, or (at 15 * your option) any later version. 16 * 17 * This program is distributed in the hope that it will be useful, but 18 * WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 * General Public License for more details. 21 * 22 * You should have received a copy of the GNU General Public License along 23 * with this program; if not, write to the Free Software Foundation, Inc., 24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 25 * 26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 27 * TBD: 28 * 1. Make # power states dynamic. 29 * 2. Support duty_cycle values that span bit 4. 30 * 3. Optimize by having scheduler determine business instead of 31 * having us try to calculate it here. 32 * 4. Need C1 timing -- must modify kernel (IRQ handler) to get this. 33 */ 34 35 #include <linux/kernel.h> 36 #include <linux/module.h> 37 #include <linux/init.h> 38 #include <linux/types.h> 39 #include <linux/pci.h> 40 #include <linux/pm.h> 41 #include <linux/cpufreq.h> 42 #include <linux/cpu.h> 43 #include <linux/dmi.h> 44 #include <linux/moduleparam.h> 45 #include <linux/cpuidle.h> 46 #include <linux/slab.h> 47 48 #include <asm/io.h> 49 #include <asm/cpu.h> 50 #include <asm/delay.h> 51 #include <asm/uaccess.h> 52 #include <asm/processor.h> 53 #include <asm/smp.h> 54 #include <asm/acpi.h> 55 56 #include <acpi/acpi_bus.h> 57 #include <acpi/acpi_drivers.h> 58 #include <acpi/processor.h> 59 60 #define PREFIX "ACPI: " 61 62 #define ACPI_PROCESSOR_CLASS "processor" 63 #define ACPI_PROCESSOR_DEVICE_NAME "Processor" 64 #define ACPI_PROCESSOR_FILE_INFO "info" 65 #define ACPI_PROCESSOR_FILE_THROTTLING "throttling" 66 #define ACPI_PROCESSOR_FILE_LIMIT "limit" 67 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80 68 #define ACPI_PROCESSOR_NOTIFY_POWER 0x81 69 #define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82 70 #define ACPI_PROCESSOR_DEVICE_HID "ACPI0007" 71 72 #define ACPI_PROCESSOR_LIMIT_USER 0 73 #define ACPI_PROCESSOR_LIMIT_THERMAL 1 74 75 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 76 ACPI_MODULE_NAME("processor_driver"); 77 78 MODULE_AUTHOR("Paul Diefenbaugh"); 79 MODULE_DESCRIPTION("ACPI Processor Driver"); 80 MODULE_LICENSE("GPL"); 81 82 static int acpi_processor_add(struct acpi_device *device); 83 static int acpi_processor_remove(struct acpi_device *device, int type); 84 static void acpi_processor_notify(struct acpi_device *device, u32 event); 85 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr); 86 static int acpi_processor_handle_eject(struct acpi_processor *pr); 87 static int acpi_processor_start(struct acpi_processor *pr); 88 89 static const struct acpi_device_id processor_device_ids[] = { 90 {ACPI_PROCESSOR_OBJECT_HID, 0}, 91 {ACPI_PROCESSOR_DEVICE_HID, 0}, 92 {"", 0}, 93 }; 94 MODULE_DEVICE_TABLE(acpi, processor_device_ids); 95 96 static SIMPLE_DEV_PM_OPS(acpi_processor_pm, 97 acpi_processor_suspend, acpi_processor_resume); 98 99 static struct acpi_driver acpi_processor_driver = { 100 .name = "processor", 101 .class = ACPI_PROCESSOR_CLASS, 102 .ids = processor_device_ids, 103 .ops = { 104 .add = acpi_processor_add, 105 .remove = acpi_processor_remove, 106 .notify = acpi_processor_notify, 107 }, 108 .drv.pm = &acpi_processor_pm, 109 }; 110 111 #define INSTALL_NOTIFY_HANDLER 1 112 #define UNINSTALL_NOTIFY_HANDLER 2 113 114 DEFINE_PER_CPU(struct acpi_processor *, processors); 115 EXPORT_PER_CPU_SYMBOL(processors); 116 117 struct acpi_processor_errata errata __read_mostly; 118 119 /* -------------------------------------------------------------------------- 120 Errata Handling 121 -------------------------------------------------------------------------- */ 122 123 static int acpi_processor_errata_piix4(struct pci_dev *dev) 124 { 125 u8 value1 = 0; 126 u8 value2 = 0; 127 128 129 if (!dev) 130 return -EINVAL; 131 132 /* 133 * Note that 'dev' references the PIIX4 ACPI Controller. 134 */ 135 136 switch (dev->revision) { 137 case 0: 138 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n")); 139 break; 140 case 1: 141 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n")); 142 break; 143 case 2: 144 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n")); 145 break; 146 case 3: 147 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n")); 148 break; 149 default: 150 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n")); 151 break; 152 } 153 154 switch (dev->revision) { 155 156 case 0: /* PIIX4 A-step */ 157 case 1: /* PIIX4 B-step */ 158 /* 159 * See specification changes #13 ("Manual Throttle Duty Cycle") 160 * and #14 ("Enabling and Disabling Manual Throttle"), plus 161 * erratum #5 ("STPCLK# Deassertion Time") from the January 162 * 2002 PIIX4 specification update. Applies to only older 163 * PIIX4 models. 164 */ 165 errata.piix4.throttle = 1; 166 167 case 2: /* PIIX4E */ 168 case 3: /* PIIX4M */ 169 /* 170 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA 171 * Livelock") from the January 2002 PIIX4 specification update. 172 * Applies to all PIIX4 models. 173 */ 174 175 /* 176 * BM-IDE 177 * ------ 178 * Find the PIIX4 IDE Controller and get the Bus Master IDE 179 * Status register address. We'll use this later to read 180 * each IDE controller's DMA status to make sure we catch all 181 * DMA activity. 182 */ 183 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 184 PCI_DEVICE_ID_INTEL_82371AB, 185 PCI_ANY_ID, PCI_ANY_ID, NULL); 186 if (dev) { 187 errata.piix4.bmisx = pci_resource_start(dev, 4); 188 pci_dev_put(dev); 189 } 190 191 /* 192 * Type-F DMA 193 * ---------- 194 * Find the PIIX4 ISA Controller and read the Motherboard 195 * DMA controller's status to see if Type-F (Fast) DMA mode 196 * is enabled (bit 7) on either channel. Note that we'll 197 * disable C3 support if this is enabled, as some legacy 198 * devices won't operate well if fast DMA is disabled. 199 */ 200 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 201 PCI_DEVICE_ID_INTEL_82371AB_0, 202 PCI_ANY_ID, PCI_ANY_ID, NULL); 203 if (dev) { 204 pci_read_config_byte(dev, 0x76, &value1); 205 pci_read_config_byte(dev, 0x77, &value2); 206 if ((value1 & 0x80) || (value2 & 0x80)) 207 errata.piix4.fdma = 1; 208 pci_dev_put(dev); 209 } 210 211 break; 212 } 213 214 if (errata.piix4.bmisx) 215 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 216 "Bus master activity detection (BM-IDE) erratum enabled\n")); 217 if (errata.piix4.fdma) 218 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 219 "Type-F DMA livelock erratum (C3 disabled)\n")); 220 221 return 0; 222 } 223 224 static int acpi_processor_errata(struct acpi_processor *pr) 225 { 226 int result = 0; 227 struct pci_dev *dev = NULL; 228 229 230 if (!pr) 231 return -EINVAL; 232 233 /* 234 * PIIX4 235 */ 236 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 237 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID, 238 PCI_ANY_ID, NULL); 239 if (dev) { 240 result = acpi_processor_errata_piix4(dev); 241 pci_dev_put(dev); 242 } 243 244 return result; 245 } 246 247 /* -------------------------------------------------------------------------- 248 Driver Interface 249 -------------------------------------------------------------------------- */ 250 251 static int acpi_processor_get_info(struct acpi_device *device) 252 { 253 acpi_status status = 0; 254 union acpi_object object = { 0 }; 255 struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; 256 struct acpi_processor *pr; 257 int cpu_index, device_declaration = 0; 258 static int cpu0_initialized; 259 260 pr = acpi_driver_data(device); 261 if (!pr) 262 return -EINVAL; 263 264 if (num_online_cpus() > 1) 265 errata.smp = TRUE; 266 267 acpi_processor_errata(pr); 268 269 /* 270 * Check to see if we have bus mastering arbitration control. This 271 * is required for proper C3 usage (to maintain cache coherency). 272 */ 273 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) { 274 pr->flags.bm_control = 1; 275 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 276 "Bus mastering arbitration control present\n")); 277 } else 278 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 279 "No bus mastering arbitration control\n")); 280 281 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) { 282 /* Declared with "Processor" statement; match ProcessorID */ 283 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer); 284 if (ACPI_FAILURE(status)) { 285 printk(KERN_ERR PREFIX "Evaluating processor object\n"); 286 return -ENODEV; 287 } 288 289 /* 290 * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP. 291 * >>> 'acpi_get_processor_id(acpi_id, &id)' in 292 * arch/xxx/acpi.c 293 */ 294 pr->acpi_id = object.processor.proc_id; 295 } else { 296 /* 297 * Declared with "Device" statement; match _UID. 298 * Note that we don't handle string _UIDs yet. 299 */ 300 unsigned long long value; 301 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID, 302 NULL, &value); 303 if (ACPI_FAILURE(status)) { 304 printk(KERN_ERR PREFIX 305 "Evaluating processor _UID [%#x]\n", status); 306 return -ENODEV; 307 } 308 device_declaration = 1; 309 pr->acpi_id = value; 310 } 311 cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id); 312 313 /* Handle UP system running SMP kernel, with no LAPIC in MADT */ 314 if (!cpu0_initialized && (cpu_index == -1) && 315 (num_online_cpus() == 1)) { 316 cpu_index = 0; 317 } 318 319 cpu0_initialized = 1; 320 321 pr->id = cpu_index; 322 323 /* 324 * Extra Processor objects may be enumerated on MP systems with 325 * less than the max # of CPUs. They should be ignored _iff 326 * they are physically not present. 327 */ 328 if (pr->id == -1) { 329 if (ACPI_FAILURE(acpi_processor_hotadd_init(pr))) 330 return -ENODEV; 331 } 332 /* 333 * On some boxes several processors use the same processor bus id. 334 * But they are located in different scope. For example: 335 * \_SB.SCK0.CPU0 336 * \_SB.SCK1.CPU0 337 * Rename the processor device bus id. And the new bus id will be 338 * generated as the following format: 339 * CPU+CPU ID. 340 */ 341 sprintf(acpi_device_bid(device), "CPU%X", pr->id); 342 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id, 343 pr->acpi_id)); 344 345 if (!object.processor.pblk_address) 346 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n")); 347 else if (object.processor.pblk_length != 6) 348 printk(KERN_ERR PREFIX "Invalid PBLK length [%d]\n", 349 object.processor.pblk_length); 350 else { 351 pr->throttling.address = object.processor.pblk_address; 352 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset; 353 pr->throttling.duty_width = acpi_gbl_FADT.duty_width; 354 355 pr->pblk = object.processor.pblk_address; 356 357 /* 358 * We don't care about error returns - we just try to mark 359 * these reserved so that nobody else is confused into thinking 360 * that this region might be unused.. 361 * 362 * (In particular, allocating the IO range for Cardbus) 363 */ 364 request_region(pr->throttling.address, 6, "ACPI CPU throttle"); 365 } 366 367 /* 368 * If ACPI describes a slot number for this CPU, we can use it 369 * ensure we get the right value in the "physical id" field 370 * of /proc/cpuinfo 371 */ 372 status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer); 373 if (ACPI_SUCCESS(status)) 374 arch_fix_phys_package_id(pr->id, object.integer.value); 375 376 return 0; 377 } 378 379 static DEFINE_PER_CPU(void *, processor_device_array); 380 381 static void acpi_processor_notify(struct acpi_device *device, u32 event) 382 { 383 struct acpi_processor *pr = acpi_driver_data(device); 384 int saved; 385 386 if (!pr) 387 return; 388 389 switch (event) { 390 case ACPI_PROCESSOR_NOTIFY_PERFORMANCE: 391 saved = pr->performance_platform_limit; 392 acpi_processor_ppc_has_changed(pr, 1); 393 if (saved == pr->performance_platform_limit) 394 break; 395 acpi_bus_generate_proc_event(device, event, 396 pr->performance_platform_limit); 397 acpi_bus_generate_netlink_event(device->pnp.device_class, 398 dev_name(&device->dev), event, 399 pr->performance_platform_limit); 400 break; 401 case ACPI_PROCESSOR_NOTIFY_POWER: 402 acpi_processor_cst_has_changed(pr); 403 acpi_bus_generate_proc_event(device, event, 0); 404 acpi_bus_generate_netlink_event(device->pnp.device_class, 405 dev_name(&device->dev), event, 0); 406 break; 407 case ACPI_PROCESSOR_NOTIFY_THROTTLING: 408 acpi_processor_tstate_has_changed(pr); 409 acpi_bus_generate_proc_event(device, event, 0); 410 acpi_bus_generate_netlink_event(device->pnp.device_class, 411 dev_name(&device->dev), event, 0); 412 break; 413 default: 414 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 415 "Unsupported event [0x%x]\n", event)); 416 break; 417 } 418 419 return; 420 } 421 422 static int acpi_cpu_soft_notify(struct notifier_block *nfb, 423 unsigned long action, void *hcpu) 424 { 425 unsigned int cpu = (unsigned long)hcpu; 426 struct acpi_processor *pr = per_cpu(processors, cpu); 427 428 if (action == CPU_ONLINE && pr) { 429 /* CPU got physically hotplugged and onlined the first time: 430 * Initialize missing things 431 */ 432 if (pr->flags.need_hotplug_init) { 433 printk(KERN_INFO "Will online and init hotplugged " 434 "CPU: %d\n", pr->id); 435 WARN(acpi_processor_start(pr), "Failed to start CPU:" 436 " %d\n", pr->id); 437 pr->flags.need_hotplug_init = 0; 438 /* Normal CPU soft online event */ 439 } else { 440 acpi_processor_ppc_has_changed(pr, 0); 441 acpi_processor_hotplug(pr); 442 acpi_processor_reevaluate_tstate(pr, action); 443 acpi_processor_tstate_has_changed(pr); 444 } 445 } 446 if (action == CPU_DEAD && pr) { 447 /* invalidate the flag.throttling after one CPU is offline */ 448 acpi_processor_reevaluate_tstate(pr, action); 449 } 450 return NOTIFY_OK; 451 } 452 453 static struct notifier_block acpi_cpu_notifier = 454 { 455 .notifier_call = acpi_cpu_soft_notify, 456 }; 457 458 /* 459 * acpi_processor_start() is called by the cpu_hotplug_notifier func: 460 * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the 461 * root cause seem to be that acpi_processor_uninstall_hotplug_notify() 462 * is in the module_exit (__exit) func. Allowing acpi_processor_start() 463 * to not be in __cpuinit section, but being called from __cpuinit funcs 464 * via __ref looks like the right thing to do here. 465 */ 466 static __ref int acpi_processor_start(struct acpi_processor *pr) 467 { 468 struct acpi_device *device = per_cpu(processor_device_array, pr->id); 469 int result = 0; 470 471 #ifdef CONFIG_CPU_FREQ 472 acpi_processor_ppc_has_changed(pr, 0); 473 acpi_processor_load_module(pr); 474 #endif 475 acpi_processor_get_throttling_info(pr); 476 acpi_processor_get_limit_info(pr); 477 478 if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver) 479 acpi_processor_power_init(pr); 480 481 pr->cdev = thermal_cooling_device_register("Processor", device, 482 &processor_cooling_ops); 483 if (IS_ERR(pr->cdev)) { 484 result = PTR_ERR(pr->cdev); 485 goto err_power_exit; 486 } 487 488 dev_dbg(&device->dev, "registered as cooling_device%d\n", 489 pr->cdev->id); 490 491 result = sysfs_create_link(&device->dev.kobj, 492 &pr->cdev->device.kobj, 493 "thermal_cooling"); 494 if (result) { 495 printk(KERN_ERR PREFIX "Create sysfs link\n"); 496 goto err_thermal_unregister; 497 } 498 result = sysfs_create_link(&pr->cdev->device.kobj, 499 &device->dev.kobj, 500 "device"); 501 if (result) { 502 printk(KERN_ERR PREFIX "Create sysfs link\n"); 503 goto err_remove_sysfs_thermal; 504 } 505 506 return 0; 507 508 err_remove_sysfs_thermal: 509 sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); 510 err_thermal_unregister: 511 thermal_cooling_device_unregister(pr->cdev); 512 err_power_exit: 513 acpi_processor_power_exit(pr); 514 515 return result; 516 } 517 518 /* 519 * Do not put anything in here which needs the core to be online. 520 * For example MSR access or setting up things which check for cpuinfo_x86 521 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc. 522 * Such things have to be put in and set up above in acpi_processor_start() 523 */ 524 static int __cpuinit acpi_processor_add(struct acpi_device *device) 525 { 526 struct acpi_processor *pr = NULL; 527 int result = 0; 528 struct device *dev; 529 530 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); 531 if (!pr) 532 return -ENOMEM; 533 534 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) { 535 result = -ENOMEM; 536 goto err_free_pr; 537 } 538 539 pr->handle = device->handle; 540 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); 541 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); 542 device->driver_data = pr; 543 544 result = acpi_processor_get_info(device); 545 if (result) { 546 /* Processor is physically not present */ 547 return 0; 548 } 549 550 #ifdef CONFIG_SMP 551 if (pr->id >= setup_max_cpus && pr->id != 0) 552 return 0; 553 #endif 554 555 BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0)); 556 557 /* 558 * Buggy BIOS check 559 * ACPI id of processors can be reported wrongly by the BIOS. 560 * Don't trust it blindly 561 */ 562 if (per_cpu(processor_device_array, pr->id) != NULL && 563 per_cpu(processor_device_array, pr->id) != device) { 564 printk(KERN_WARNING "BIOS reported wrong ACPI id " 565 "for the processor\n"); 566 result = -ENODEV; 567 goto err_free_cpumask; 568 } 569 per_cpu(processor_device_array, pr->id) = device; 570 571 per_cpu(processors, pr->id) = pr; 572 573 dev = get_cpu_device(pr->id); 574 if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) { 575 result = -EFAULT; 576 goto err_clear_processor; 577 } 578 579 /* 580 * Do not start hotplugged CPUs now, but when they 581 * are onlined the first time 582 */ 583 if (pr->flags.need_hotplug_init) 584 return 0; 585 586 result = acpi_processor_start(pr); 587 if (result) 588 goto err_remove_sysfs; 589 590 return 0; 591 592 err_remove_sysfs: 593 sysfs_remove_link(&device->dev.kobj, "sysdev"); 594 err_clear_processor: 595 /* 596 * processor_device_array is not cleared to allow checks for buggy BIOS 597 */ 598 per_cpu(processors, pr->id) = NULL; 599 err_free_cpumask: 600 free_cpumask_var(pr->throttling.shared_cpu_map); 601 err_free_pr: 602 kfree(pr); 603 return result; 604 } 605 606 static int acpi_processor_remove(struct acpi_device *device, int type) 607 { 608 struct acpi_processor *pr = NULL; 609 610 611 if (!device || !acpi_driver_data(device)) 612 return -EINVAL; 613 614 pr = acpi_driver_data(device); 615 616 if (pr->id >= nr_cpu_ids) 617 goto free; 618 619 if (type == ACPI_BUS_REMOVAL_EJECT) { 620 if (acpi_processor_handle_eject(pr)) 621 return -EINVAL; 622 } 623 624 acpi_processor_power_exit(pr); 625 626 sysfs_remove_link(&device->dev.kobj, "sysdev"); 627 628 if (pr->cdev) { 629 sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); 630 sysfs_remove_link(&pr->cdev->device.kobj, "device"); 631 thermal_cooling_device_unregister(pr->cdev); 632 pr->cdev = NULL; 633 } 634 635 per_cpu(processors, pr->id) = NULL; 636 per_cpu(processor_device_array, pr->id) = NULL; 637 638 free: 639 free_cpumask_var(pr->throttling.shared_cpu_map); 640 kfree(pr); 641 642 return 0; 643 } 644 645 #ifdef CONFIG_ACPI_HOTPLUG_CPU 646 /**************************************************************************** 647 * Acpi processor hotplug support * 648 ****************************************************************************/ 649 650 static int is_processor_present(acpi_handle handle) 651 { 652 acpi_status status; 653 unsigned long long sta = 0; 654 655 656 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); 657 658 if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT)) 659 return 1; 660 661 /* 662 * _STA is mandatory for a processor that supports hot plug 663 */ 664 if (status == AE_NOT_FOUND) 665 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 666 "Processor does not support hot plug\n")); 667 else 668 ACPI_EXCEPTION((AE_INFO, status, 669 "Processor Device is not present")); 670 return 0; 671 } 672 673 static 674 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device) 675 { 676 acpi_handle phandle; 677 struct acpi_device *pdev; 678 679 680 if (acpi_get_parent(handle, &phandle)) { 681 return -ENODEV; 682 } 683 684 if (acpi_bus_get_device(phandle, &pdev)) { 685 return -ENODEV; 686 } 687 688 if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) { 689 return -ENODEV; 690 } 691 692 return 0; 693 } 694 695 static void acpi_processor_hotplug_notify(acpi_handle handle, 696 u32 event, void *data) 697 { 698 struct acpi_processor *pr; 699 struct acpi_device *device = NULL; 700 u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */ 701 int result; 702 703 switch (event) { 704 case ACPI_NOTIFY_BUS_CHECK: 705 case ACPI_NOTIFY_DEVICE_CHECK: 706 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 707 "Processor driver received %s event\n", 708 (event == ACPI_NOTIFY_BUS_CHECK) ? 709 "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK")); 710 711 if (!is_processor_present(handle)) 712 break; 713 714 if (!acpi_bus_get_device(handle, &device)) 715 break; 716 717 result = acpi_processor_device_add(handle, &device); 718 if (result) { 719 printk(KERN_ERR PREFIX "Unable to add the device\n"); 720 break; 721 } 722 723 ost_code = ACPI_OST_SC_SUCCESS; 724 break; 725 726 case ACPI_NOTIFY_EJECT_REQUEST: 727 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 728 "received ACPI_NOTIFY_EJECT_REQUEST\n")); 729 730 if (acpi_bus_get_device(handle, &device)) { 731 printk(KERN_ERR PREFIX 732 "Device don't exist, dropping EJECT\n"); 733 break; 734 } 735 pr = acpi_driver_data(device); 736 if (!pr) { 737 printk(KERN_ERR PREFIX 738 "Driver data is NULL, dropping EJECT\n"); 739 break; 740 } 741 742 /* REVISIT: update when eject is supported */ 743 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED; 744 break; 745 746 default: 747 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 748 "Unsupported event [0x%x]\n", event)); 749 750 /* non-hotplug event; possibly handled by other handler */ 751 return; 752 } 753 754 /* Inform firmware that the hotplug operation has completed */ 755 (void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL); 756 return; 757 } 758 759 static acpi_status is_processor_device(acpi_handle handle) 760 { 761 struct acpi_device_info *info; 762 char *hid; 763 acpi_status status; 764 765 status = acpi_get_object_info(handle, &info); 766 if (ACPI_FAILURE(status)) 767 return status; 768 769 if (info->type == ACPI_TYPE_PROCESSOR) { 770 kfree(info); 771 return AE_OK; /* found a processor object */ 772 } 773 774 if (!(info->valid & ACPI_VALID_HID)) { 775 kfree(info); 776 return AE_ERROR; 777 } 778 779 hid = info->hardware_id.string; 780 if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) { 781 kfree(info); 782 return AE_ERROR; 783 } 784 785 kfree(info); 786 return AE_OK; /* found a processor device object */ 787 } 788 789 static acpi_status 790 processor_walk_namespace_cb(acpi_handle handle, 791 u32 lvl, void *context, void **rv) 792 { 793 acpi_status status; 794 int *action = context; 795 796 status = is_processor_device(handle); 797 if (ACPI_FAILURE(status)) 798 return AE_OK; /* not a processor; continue to walk */ 799 800 switch (*action) { 801 case INSTALL_NOTIFY_HANDLER: 802 acpi_install_notify_handler(handle, 803 ACPI_SYSTEM_NOTIFY, 804 acpi_processor_hotplug_notify, 805 NULL); 806 break; 807 case UNINSTALL_NOTIFY_HANDLER: 808 acpi_remove_notify_handler(handle, 809 ACPI_SYSTEM_NOTIFY, 810 acpi_processor_hotplug_notify); 811 break; 812 default: 813 break; 814 } 815 816 /* found a processor; skip walking underneath */ 817 return AE_CTRL_DEPTH; 818 } 819 820 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) 821 { 822 acpi_handle handle = pr->handle; 823 824 if (!is_processor_present(handle)) { 825 return AE_ERROR; 826 } 827 828 if (acpi_map_lsapic(handle, &pr->id)) 829 return AE_ERROR; 830 831 if (arch_register_cpu(pr->id)) { 832 acpi_unmap_lsapic(pr->id); 833 return AE_ERROR; 834 } 835 836 /* CPU got hot-plugged, but cpu_data is not initialized yet 837 * Set flag to delay cpu_idle/throttling initialization 838 * in: 839 * acpi_processor_add() 840 * acpi_processor_get_info() 841 * and do it when the CPU gets online the first time 842 * TBD: Cleanup above functions and try to do this more elegant. 843 */ 844 printk(KERN_INFO "CPU %d got hotplugged\n", pr->id); 845 pr->flags.need_hotplug_init = 1; 846 847 return AE_OK; 848 } 849 850 static int acpi_processor_handle_eject(struct acpi_processor *pr) 851 { 852 if (cpu_online(pr->id)) 853 cpu_down(pr->id); 854 855 arch_unregister_cpu(pr->id); 856 acpi_unmap_lsapic(pr->id); 857 return (0); 858 } 859 #else 860 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) 861 { 862 return AE_ERROR; 863 } 864 static int acpi_processor_handle_eject(struct acpi_processor *pr) 865 { 866 return (-EINVAL); 867 } 868 #endif 869 870 static 871 void acpi_processor_install_hotplug_notify(void) 872 { 873 #ifdef CONFIG_ACPI_HOTPLUG_CPU 874 int action = INSTALL_NOTIFY_HANDLER; 875 acpi_walk_namespace(ACPI_TYPE_ANY, 876 ACPI_ROOT_OBJECT, 877 ACPI_UINT32_MAX, 878 processor_walk_namespace_cb, NULL, &action, NULL); 879 #endif 880 register_hotcpu_notifier(&acpi_cpu_notifier); 881 } 882 883 static 884 void acpi_processor_uninstall_hotplug_notify(void) 885 { 886 #ifdef CONFIG_ACPI_HOTPLUG_CPU 887 int action = UNINSTALL_NOTIFY_HANDLER; 888 acpi_walk_namespace(ACPI_TYPE_ANY, 889 ACPI_ROOT_OBJECT, 890 ACPI_UINT32_MAX, 891 processor_walk_namespace_cb, NULL, &action, NULL); 892 #endif 893 unregister_hotcpu_notifier(&acpi_cpu_notifier); 894 } 895 896 /* 897 * We keep the driver loaded even when ACPI is not running. 898 * This is needed for the powernow-k8 driver, that works even without 899 * ACPI, but needs symbols from this driver 900 */ 901 902 static int __init acpi_processor_init(void) 903 { 904 int result = 0; 905 906 if (acpi_disabled) 907 return 0; 908 909 result = acpi_bus_register_driver(&acpi_processor_driver); 910 if (result < 0) 911 return result; 912 913 acpi_processor_install_hotplug_notify(); 914 915 acpi_thermal_cpufreq_init(); 916 917 acpi_processor_ppc_init(); 918 919 acpi_processor_throttling_init(); 920 921 return 0; 922 } 923 924 static void __exit acpi_processor_exit(void) 925 { 926 if (acpi_disabled) 927 return; 928 929 acpi_processor_ppc_exit(); 930 931 acpi_thermal_cpufreq_exit(); 932 933 acpi_processor_uninstall_hotplug_notify(); 934 935 acpi_bus_unregister_driver(&acpi_processor_driver); 936 937 return; 938 } 939 940 module_init(acpi_processor_init); 941 module_exit(acpi_processor_exit); 942 943 MODULE_ALIAS("processor"); 944