2 * acpi_processor.c - ACPI Processor Driver ($Revision: 71 $)
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
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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>
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>
50 #include <asm/delay.h>
51 #include <asm/uaccess.h>
52 #include <asm/processor.h>
56 #include <acpi/acpi_bus.h>
57 #include <acpi/acpi_drivers.h>
58 #include <acpi/processor.h>
60 #define PREFIX "ACPI: "
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"
72 #define ACPI_PROCESSOR_LIMIT_USER 0
73 #define ACPI_PROCESSOR_LIMIT_THERMAL 1
75 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
76 ACPI_MODULE_NAME("processor_driver");
78 MODULE_AUTHOR("Paul Diefenbaugh");
79 MODULE_DESCRIPTION("ACPI Processor Driver");
80 MODULE_LICENSE("GPL");
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);
89 static const struct acpi_device_id processor_device_ids[] = {
90 {ACPI_PROCESSOR_OBJECT_HID, 0},
91 {ACPI_PROCESSOR_DEVICE_HID, 0},
94 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
96 static SIMPLE_DEV_PM_OPS(acpi_processor_pm,
97 acpi_processor_suspend, acpi_processor_resume);
99 static struct acpi_driver acpi_processor_driver = {
101 .class = ACPI_PROCESSOR_CLASS,
102 .ids = processor_device_ids,
104 .add = acpi_processor_add,
105 .remove = acpi_processor_remove,
106 .notify = acpi_processor_notify,
108 .drv.pm = &acpi_processor_pm,
111 #define INSTALL_NOTIFY_HANDLER 1
112 #define UNINSTALL_NOTIFY_HANDLER 2
114 DEFINE_PER_CPU(struct acpi_processor *, processors);
115 EXPORT_PER_CPU_SYMBOL(processors);
117 struct acpi_processor_errata errata __read_mostly;
119 /* --------------------------------------------------------------------------
121 -------------------------------------------------------------------------- */
123 static int acpi_processor_errata_piix4(struct pci_dev *dev)
133 * Note that 'dev' references the PIIX4 ACPI Controller.
136 switch (dev->revision) {
138 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
141 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
144 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
147 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
150 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
154 switch (dev->revision) {
156 case 0: /* PIIX4 A-step */
157 case 1: /* PIIX4 B-step */
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
165 errata.piix4.throttle = 1;
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.
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
183 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
184 PCI_DEVICE_ID_INTEL_82371AB,
185 PCI_ANY_ID, PCI_ANY_ID, NULL);
187 errata.piix4.bmisx = pci_resource_start(dev, 4);
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.
200 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
201 PCI_DEVICE_ID_INTEL_82371AB_0,
202 PCI_ANY_ID, PCI_ANY_ID, NULL);
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;
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"));
224 static int acpi_processor_errata(struct acpi_processor *pr)
227 struct pci_dev *dev = NULL;
236 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
237 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
240 result = acpi_processor_errata_piix4(dev);
247 /* --------------------------------------------------------------------------
249 -------------------------------------------------------------------------- */
251 static int acpi_processor_get_info(struct acpi_device *device)
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;
260 pr = acpi_driver_data(device);
264 if (num_online_cpus() > 1)
267 acpi_processor_errata(pr);
270 * Check to see if we have bus mastering arbitration control. This
271 * is required for proper C3 usage (to maintain cache coherency).
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"));
278 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
279 "No bus mastering arbitration control\n"));
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");
290 * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
291 * >>> 'acpi_get_processor_id(acpi_id, &id)' in
294 pr->acpi_id = object.processor.proc_id;
297 * Declared with "Device" statement; match _UID.
298 * Note that we don't handle string _UIDs yet.
300 unsigned long long value;
301 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
303 if (ACPI_FAILURE(status)) {
304 printk(KERN_ERR PREFIX
305 "Evaluating processor _UID [%#x]\n", status);
308 device_declaration = 1;
311 cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id);
313 /* Handle UP system running SMP kernel, with no LAPIC in MADT */
314 if (!cpu0_initialized && (cpu_index == -1) &&
315 (num_online_cpus() == 1)) {
319 cpu0_initialized = 1;
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.
329 if (ACPI_FAILURE(acpi_processor_hotadd_init(pr)))
333 * On some boxes several processors use the same processor bus id.
334 * But they are located in different scope. For example:
337 * Rename the processor device bus id. And the new bus id will be
338 * generated as the following format:
341 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
342 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
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);
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;
355 pr->pblk = object.processor.pblk_address;
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..
362 * (In particular, allocating the IO range for Cardbus)
364 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
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
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);
379 static DEFINE_PER_CPU(void *, processor_device_array);
381 static void acpi_processor_notify(struct acpi_device *device, u32 event)
383 struct acpi_processor *pr = acpi_driver_data(device);
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)
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);
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);
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);
414 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
415 "Unsupported event [0x%x]\n", event));
422 static int acpi_cpu_soft_notify(struct notifier_block *nfb,
423 unsigned long action, void *hcpu)
425 unsigned int cpu = (unsigned long)hcpu;
426 struct acpi_processor *pr = per_cpu(processors, cpu);
428 if (action == CPU_ONLINE && pr) {
429 /* CPU got physically hotplugged and onlined the first time:
430 * Initialize missing things
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:"
437 pr->flags.need_hotplug_init = 0;
438 /* Normal CPU soft online event */
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);
446 if (action == CPU_DEAD && pr) {
447 /* invalidate the flag.throttling after one CPU is offline */
448 acpi_processor_reevaluate_tstate(pr, action);
453 static struct notifier_block acpi_cpu_notifier =
455 .notifier_call = acpi_cpu_soft_notify,
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.
466 static __ref int acpi_processor_start(struct acpi_processor *pr)
468 struct acpi_device *device = per_cpu(processor_device_array, pr->id);
471 #ifdef CONFIG_CPU_FREQ
472 acpi_processor_ppc_has_changed(pr, 0);
473 acpi_processor_load_module(pr);
475 acpi_processor_get_throttling_info(pr);
476 acpi_processor_get_limit_info(pr);
478 if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
479 acpi_processor_power_init(pr);
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);
488 dev_dbg(&device->dev, "registered as cooling_device%d\n",
491 result = sysfs_create_link(&device->dev.kobj,
492 &pr->cdev->device.kobj,
495 printk(KERN_ERR PREFIX "Create sysfs link\n");
496 goto err_thermal_unregister;
498 result = sysfs_create_link(&pr->cdev->device.kobj,
502 printk(KERN_ERR PREFIX "Create sysfs link\n");
503 goto err_remove_sysfs_thermal;
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);
513 acpi_processor_power_exit(pr);
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()
524 static int __cpuinit acpi_processor_add(struct acpi_device *device)
526 struct acpi_processor *pr = NULL;
530 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
534 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
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;
544 result = acpi_processor_get_info(device);
546 /* Processor is physically not present */
551 if (pr->id >= setup_max_cpus && pr->id != 0)
555 BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0));
559 * ACPI id of processors can be reported wrongly by the BIOS.
560 * Don't trust it blindly
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");
567 goto err_free_cpumask;
569 per_cpu(processor_device_array, pr->id) = device;
571 per_cpu(processors, pr->id) = pr;
573 dev = get_cpu_device(pr->id);
574 if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
576 goto err_clear_processor;
580 * Do not start hotplugged CPUs now, but when they
581 * are onlined the first time
583 if (pr->flags.need_hotplug_init)
586 result = acpi_processor_start(pr);
588 goto err_remove_sysfs;
593 sysfs_remove_link(&device->dev.kobj, "sysdev");
596 * processor_device_array is not cleared to allow checks for buggy BIOS
598 per_cpu(processors, pr->id) = NULL;
600 free_cpumask_var(pr->throttling.shared_cpu_map);
606 static int acpi_processor_remove(struct acpi_device *device, int type)
608 struct acpi_processor *pr = NULL;
611 if (!device || !acpi_driver_data(device))
614 pr = acpi_driver_data(device);
616 if (pr->id >= nr_cpu_ids)
619 if (type == ACPI_BUS_REMOVAL_EJECT) {
620 if (acpi_processor_handle_eject(pr))
624 acpi_processor_power_exit(pr);
626 sysfs_remove_link(&device->dev.kobj, "sysdev");
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);
635 per_cpu(processors, pr->id) = NULL;
636 per_cpu(processor_device_array, pr->id) = NULL;
639 free_cpumask_var(pr->throttling.shared_cpu_map);
645 #ifdef CONFIG_ACPI_HOTPLUG_CPU
646 /****************************************************************************
647 * Acpi processor hotplug support *
648 ****************************************************************************/
650 static int is_processor_present(acpi_handle handle)
653 unsigned long long sta = 0;
656 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
658 if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
662 * _STA is mandatory for a processor that supports hot plug
664 if (status == AE_NOT_FOUND)
665 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
666 "Processor does not support hot plug\n"));
668 ACPI_EXCEPTION((AE_INFO, status,
669 "Processor Device is not present"));
674 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
677 struct acpi_device *pdev;
680 if (acpi_get_parent(handle, &phandle)) {
684 if (acpi_bus_get_device(phandle, &pdev)) {
688 if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
695 static void acpi_processor_hotplug_notify(acpi_handle handle,
696 u32 event, void *data)
698 struct acpi_processor *pr;
699 struct acpi_device *device = NULL;
700 u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
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"));
711 if (!is_processor_present(handle))
714 if (!acpi_bus_get_device(handle, &device))
717 result = acpi_processor_device_add(handle, &device);
719 printk(KERN_ERR PREFIX "Unable to add the device\n");
723 ost_code = ACPI_OST_SC_SUCCESS;
726 case ACPI_NOTIFY_EJECT_REQUEST:
727 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
728 "received ACPI_NOTIFY_EJECT_REQUEST\n"));
730 if (acpi_bus_get_device(handle, &device)) {
731 printk(KERN_ERR PREFIX
732 "Device don't exist, dropping EJECT\n");
735 pr = acpi_driver_data(device);
737 printk(KERN_ERR PREFIX
738 "Driver data is NULL, dropping EJECT\n");
742 /* REVISIT: update when eject is supported */
743 ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
747 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
748 "Unsupported event [0x%x]\n", event));
750 /* non-hotplug event; possibly handled by other handler */
754 /* Inform firmware that the hotplug operation has completed */
755 (void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL);
759 static acpi_status is_processor_device(acpi_handle handle)
761 struct acpi_device_info *info;
765 status = acpi_get_object_info(handle, &info);
766 if (ACPI_FAILURE(status))
769 if (info->type == ACPI_TYPE_PROCESSOR) {
771 return AE_OK; /* found a processor object */
774 if (!(info->valid & ACPI_VALID_HID)) {
779 hid = info->hardware_id.string;
780 if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) {
786 return AE_OK; /* found a processor device object */
790 processor_walk_namespace_cb(acpi_handle handle,
791 u32 lvl, void *context, void **rv)
794 int *action = context;
796 status = is_processor_device(handle);
797 if (ACPI_FAILURE(status))
798 return AE_OK; /* not a processor; continue to walk */
801 case INSTALL_NOTIFY_HANDLER:
802 acpi_install_notify_handler(handle,
804 acpi_processor_hotplug_notify,
807 case UNINSTALL_NOTIFY_HANDLER:
808 acpi_remove_notify_handler(handle,
810 acpi_processor_hotplug_notify);
816 /* found a processor; skip walking underneath */
817 return AE_CTRL_DEPTH;
820 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
822 acpi_handle handle = pr->handle;
824 if (!is_processor_present(handle)) {
828 if (acpi_map_lsapic(handle, &pr->id))
831 if (arch_register_cpu(pr->id)) {
832 acpi_unmap_lsapic(pr->id);
836 /* CPU got hot-plugged, but cpu_data is not initialized yet
837 * Set flag to delay cpu_idle/throttling initialization
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.
844 printk(KERN_INFO "CPU %d got hotplugged\n", pr->id);
845 pr->flags.need_hotplug_init = 1;
850 static int acpi_processor_handle_eject(struct acpi_processor *pr)
852 if (cpu_online(pr->id))
857 * The cpu might become online again at this point. So we check whether
858 * the cpu has been onlined or not. If the cpu became online, it means
859 * that someone wants to use the cpu. So acpi_processor_handle_eject()
862 if (unlikely(cpu_online(pr->id))) {
864 pr_warn("Failed to remove CPU %d, because other task "
865 "brought the CPU back online\n", pr->id);
868 arch_unregister_cpu(pr->id);
869 acpi_unmap_lsapic(pr->id);
874 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
878 static int acpi_processor_handle_eject(struct acpi_processor *pr)
885 void acpi_processor_install_hotplug_notify(void)
887 #ifdef CONFIG_ACPI_HOTPLUG_CPU
888 int action = INSTALL_NOTIFY_HANDLER;
889 acpi_walk_namespace(ACPI_TYPE_ANY,
892 processor_walk_namespace_cb, NULL, &action, NULL);
894 register_hotcpu_notifier(&acpi_cpu_notifier);
898 void acpi_processor_uninstall_hotplug_notify(void)
900 #ifdef CONFIG_ACPI_HOTPLUG_CPU
901 int action = UNINSTALL_NOTIFY_HANDLER;
902 acpi_walk_namespace(ACPI_TYPE_ANY,
905 processor_walk_namespace_cb, NULL, &action, NULL);
907 unregister_hotcpu_notifier(&acpi_cpu_notifier);
911 * We keep the driver loaded even when ACPI is not running.
912 * This is needed for the powernow-k8 driver, that works even without
913 * ACPI, but needs symbols from this driver
916 static int __init acpi_processor_init(void)
923 result = acpi_bus_register_driver(&acpi_processor_driver);
927 acpi_processor_install_hotplug_notify();
929 acpi_thermal_cpufreq_init();
931 acpi_processor_ppc_init();
933 acpi_processor_throttling_init();
938 static void __exit acpi_processor_exit(void)
943 acpi_processor_ppc_exit();
945 acpi_thermal_cpufreq_exit();
947 acpi_processor_uninstall_hotplug_notify();
949 acpi_bus_unregister_driver(&acpi_processor_driver);
954 module_init(acpi_processor_init);
955 module_exit(acpi_processor_exit);
957 MODULE_ALIAS("processor");