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 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 result = -ENOMEM; 540 goto err_free_pr; 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_clear_processor; 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_clear_processor: 599 /* 600 * processor_device_array is not cleared to allow checks for buggy BIOS 601 */ 602 per_cpu(processors, pr->id) = NULL; 603 err_free_cpumask: 604 free_cpumask_var(pr->throttling.shared_cpu_map); 605 err_free_pr: 606 kfree(pr); 607 return result; 608 } 609 610 static int acpi_processor_remove(struct acpi_device *device, int type) 611 { 612 struct acpi_processor *pr = NULL; 613 614 615 if (!device || !acpi_driver_data(device)) 616 return -EINVAL; 617 618 pr = acpi_driver_data(device); 619 620 if (pr->id >= nr_cpu_ids) 621 goto free; 622 623 if (type == ACPI_BUS_REMOVAL_EJECT) { 624 if (acpi_processor_handle_eject(pr)) 625 return -EINVAL; 626 } 627 628 acpi_processor_power_exit(pr, device); 629 630 sysfs_remove_link(&device->dev.kobj, "sysdev"); 631 632 if (pr->cdev) { 633 sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); 634 sysfs_remove_link(&pr->cdev->device.kobj, "device"); 635 thermal_cooling_device_unregister(pr->cdev); 636 pr->cdev = NULL; 637 } 638 639 per_cpu(processors, pr->id) = NULL; 640 per_cpu(processor_device_array, pr->id) = NULL; 641 642 free: 643 free_cpumask_var(pr->throttling.shared_cpu_map); 644 kfree(pr); 645 646 return 0; 647 } 648 649 #ifdef CONFIG_ACPI_HOTPLUG_CPU 650 /**************************************************************************** 651 * Acpi processor hotplug support * 652 ****************************************************************************/ 653 654 static int is_processor_present(acpi_handle handle) 655 { 656 acpi_status status; 657 unsigned long long sta = 0; 658 659 660 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); 661 662 if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT)) 663 return 1; 664 665 /* 666 * _STA is mandatory for a processor that supports hot plug 667 */ 668 if (status == AE_NOT_FOUND) 669 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 670 "Processor does not support hot plug\n")); 671 else 672 ACPI_EXCEPTION((AE_INFO, status, 673 "Processor Device is not present")); 674 return 0; 675 } 676 677 static 678 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device) 679 { 680 acpi_handle phandle; 681 struct acpi_device *pdev; 682 683 684 if (acpi_get_parent(handle, &phandle)) { 685 return -ENODEV; 686 } 687 688 if (acpi_bus_get_device(phandle, &pdev)) { 689 return -ENODEV; 690 } 691 692 if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) { 693 return -ENODEV; 694 } 695 696 return 0; 697 } 698 699 static void acpi_processor_hotplug_notify(acpi_handle handle, 700 u32 event, void *data) 701 { 702 struct acpi_processor *pr; 703 struct acpi_device *device = NULL; 704 int result; 705 706 707 switch (event) { 708 case ACPI_NOTIFY_BUS_CHECK: 709 case ACPI_NOTIFY_DEVICE_CHECK: 710 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 711 "Processor driver received %s event\n", 712 (event == ACPI_NOTIFY_BUS_CHECK) ? 713 "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK")); 714 715 if (!is_processor_present(handle)) 716 break; 717 718 if (acpi_bus_get_device(handle, &device)) { 719 result = acpi_processor_device_add(handle, &device); 720 if (result) 721 printk(KERN_ERR PREFIX 722 "Unable to add the device\n"); 723 break; 724 } 725 break; 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 return; 740 } 741 break; 742 default: 743 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 744 "Unsupported event [0x%x]\n", event)); 745 break; 746 } 747 748 return; 749 } 750 751 static acpi_status is_processor_device(acpi_handle handle) 752 { 753 struct acpi_device_info *info; 754 char *hid; 755 acpi_status status; 756 757 status = acpi_get_object_info(handle, &info); 758 if (ACPI_FAILURE(status)) 759 return status; 760 761 if (info->type == ACPI_TYPE_PROCESSOR) { 762 kfree(info); 763 return AE_OK; /* found a processor object */ 764 } 765 766 if (!(info->valid & ACPI_VALID_HID)) { 767 kfree(info); 768 return AE_ERROR; 769 } 770 771 hid = info->hardware_id.string; 772 if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) { 773 kfree(info); 774 return AE_ERROR; 775 } 776 777 kfree(info); 778 return AE_OK; /* found a processor device object */ 779 } 780 781 static acpi_status 782 processor_walk_namespace_cb(acpi_handle handle, 783 u32 lvl, void *context, void **rv) 784 { 785 acpi_status status; 786 int *action = context; 787 788 status = is_processor_device(handle); 789 if (ACPI_FAILURE(status)) 790 return AE_OK; /* not a processor; continue to walk */ 791 792 switch (*action) { 793 case INSTALL_NOTIFY_HANDLER: 794 acpi_install_notify_handler(handle, 795 ACPI_SYSTEM_NOTIFY, 796 acpi_processor_hotplug_notify, 797 NULL); 798 break; 799 case UNINSTALL_NOTIFY_HANDLER: 800 acpi_remove_notify_handler(handle, 801 ACPI_SYSTEM_NOTIFY, 802 acpi_processor_hotplug_notify); 803 break; 804 default: 805 break; 806 } 807 808 /* found a processor; skip walking underneath */ 809 return AE_CTRL_DEPTH; 810 } 811 812 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) 813 { 814 acpi_handle handle = pr->handle; 815 816 if (!is_processor_present(handle)) { 817 return AE_ERROR; 818 } 819 820 if (acpi_map_lsapic(handle, &pr->id)) 821 return AE_ERROR; 822 823 if (arch_register_cpu(pr->id)) { 824 acpi_unmap_lsapic(pr->id); 825 return AE_ERROR; 826 } 827 828 /* CPU got hot-plugged, but cpu_data is not initialized yet 829 * Set flag to delay cpu_idle/throttling initialization 830 * in: 831 * acpi_processor_add() 832 * acpi_processor_get_info() 833 * and do it when the CPU gets online the first time 834 * TBD: Cleanup above functions and try to do this more elegant. 835 */ 836 printk(KERN_INFO "CPU %d got hotplugged\n", pr->id); 837 pr->flags.need_hotplug_init = 1; 838 839 return AE_OK; 840 } 841 842 static int acpi_processor_handle_eject(struct acpi_processor *pr) 843 { 844 if (cpu_online(pr->id)) 845 cpu_down(pr->id); 846 847 arch_unregister_cpu(pr->id); 848 acpi_unmap_lsapic(pr->id); 849 return (0); 850 } 851 #else 852 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) 853 { 854 return AE_ERROR; 855 } 856 static int acpi_processor_handle_eject(struct acpi_processor *pr) 857 { 858 return (-EINVAL); 859 } 860 #endif 861 862 static 863 void acpi_processor_install_hotplug_notify(void) 864 { 865 #ifdef CONFIG_ACPI_HOTPLUG_CPU 866 int action = INSTALL_NOTIFY_HANDLER; 867 acpi_walk_namespace(ACPI_TYPE_ANY, 868 ACPI_ROOT_OBJECT, 869 ACPI_UINT32_MAX, 870 processor_walk_namespace_cb, NULL, &action, NULL); 871 #endif 872 register_hotcpu_notifier(&acpi_cpu_notifier); 873 } 874 875 static 876 void acpi_processor_uninstall_hotplug_notify(void) 877 { 878 #ifdef CONFIG_ACPI_HOTPLUG_CPU 879 int action = UNINSTALL_NOTIFY_HANDLER; 880 acpi_walk_namespace(ACPI_TYPE_ANY, 881 ACPI_ROOT_OBJECT, 882 ACPI_UINT32_MAX, 883 processor_walk_namespace_cb, NULL, &action, NULL); 884 #endif 885 unregister_hotcpu_notifier(&acpi_cpu_notifier); 886 } 887 888 /* 889 * We keep the driver loaded even when ACPI is not running. 890 * This is needed for the powernow-k8 driver, that works even without 891 * ACPI, but needs symbols from this driver 892 */ 893 894 static int __init acpi_processor_init(void) 895 { 896 int result = 0; 897 898 if (acpi_disabled) 899 return 0; 900 901 memset(&errata, 0, sizeof(errata)); 902 903 result = acpi_bus_register_driver(&acpi_processor_driver); 904 if (result < 0) 905 return result; 906 907 acpi_processor_install_hotplug_notify(); 908 909 acpi_thermal_cpufreq_init(); 910 911 acpi_processor_ppc_init(); 912 913 acpi_processor_throttling_init(); 914 915 return 0; 916 } 917 918 static void __exit acpi_processor_exit(void) 919 { 920 if (acpi_disabled) 921 return; 922 923 acpi_processor_ppc_exit(); 924 925 acpi_thermal_cpufreq_exit(); 926 927 acpi_processor_uninstall_hotplug_notify(); 928 929 acpi_bus_unregister_driver(&acpi_processor_driver); 930 931 return; 932 } 933 934 module_init(acpi_processor_init); 935 module_exit(acpi_processor_exit); 936 937 MODULE_ALIAS("processor"); 938