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/proc_fs.h>
44 #include <linux/seq_file.h>
45 #include <linux/dmi.h>
46 #include <linux/moduleparam.h>
49 #include <asm/system.h>
51 #include <asm/delay.h>
52 #include <asm/uaccess.h>
53 #include <asm/processor.h>
57 #include <acpi/acpi_bus.h>
58 #include <acpi/acpi_drivers.h>
59 #include <acpi/processor.h>
61 #define ACPI_PROCESSOR_COMPONENT 0x01000000
62 #define ACPI_PROCESSOR_CLASS "processor"
63 #define ACPI_PROCESSOR_DRIVER_NAME "ACPI Processor Driver"
64 #define ACPI_PROCESSOR_DEVICE_NAME "Processor"
65 #define ACPI_PROCESSOR_FILE_INFO "info"
66 #define ACPI_PROCESSOR_FILE_THROTTLING "throttling"
67 #define ACPI_PROCESSOR_FILE_LIMIT "limit"
68 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
69 #define ACPI_PROCESSOR_NOTIFY_POWER 0x81
71 #define ACPI_PROCESSOR_LIMIT_USER 0
72 #define ACPI_PROCESSOR_LIMIT_THERMAL 1
74 #define ACPI_STA_PRESENT 0x00000001
76 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
77 ACPI_MODULE_NAME("acpi_processor")
79 MODULE_AUTHOR("Paul Diefenbaugh");
80 MODULE_DESCRIPTION(ACPI_PROCESSOR_DRIVER_NAME);
81 MODULE_LICENSE("GPL");
83 static int acpi_processor_add(struct acpi_device *device);
84 static int acpi_processor_start(struct acpi_device *device);
85 static int acpi_processor_remove(struct acpi_device *device, int type);
86 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file);
87 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data);
88 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu);
89 static int acpi_processor_handle_eject(struct acpi_processor *pr);
91 static struct acpi_driver acpi_processor_driver = {
92 .name = ACPI_PROCESSOR_DRIVER_NAME,
93 .class = ACPI_PROCESSOR_CLASS,
94 .ids = ACPI_PROCESSOR_HID,
96 .add = acpi_processor_add,
97 .remove = acpi_processor_remove,
98 .start = acpi_processor_start,
102 #define INSTALL_NOTIFY_HANDLER 1
103 #define UNINSTALL_NOTIFY_HANDLER 2
105 static const struct file_operations acpi_processor_info_fops = {
106 .open = acpi_processor_info_open_fs,
109 .release = single_release,
112 struct acpi_processor *processors[NR_CPUS];
113 struct acpi_processor_errata errata __read_mostly;
115 /* --------------------------------------------------------------------------
117 -------------------------------------------------------------------------- */
119 static int acpi_processor_errata_piix4(struct pci_dev *dev)
130 * Note that 'dev' references the PIIX4 ACPI Controller.
133 pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
137 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
140 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
143 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
146 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
149 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
155 case 0: /* PIIX4 A-step */
156 case 1: /* PIIX4 B-step */
158 * See specification changes #13 ("Manual Throttle Duty Cycle")
159 * and #14 ("Enabling and Disabling Manual Throttle"), plus
160 * erratum #5 ("STPCLK# Deassertion Time") from the January
161 * 2002 PIIX4 specification update. Applies to only older
164 errata.piix4.throttle = 1;
169 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
170 * Livelock") from the January 2002 PIIX4 specification update.
171 * Applies to all PIIX4 models.
177 * Find the PIIX4 IDE Controller and get the Bus Master IDE
178 * Status register address. We'll use this later to read
179 * each IDE controller's DMA status to make sure we catch all
182 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
183 PCI_DEVICE_ID_INTEL_82371AB,
184 PCI_ANY_ID, PCI_ANY_ID, NULL);
186 errata.piix4.bmisx = pci_resource_start(dev, 4);
193 * Find the PIIX4 ISA Controller and read the Motherboard
194 * DMA controller's status to see if Type-F (Fast) DMA mode
195 * is enabled (bit 7) on either channel. Note that we'll
196 * disable C3 support if this is enabled, as some legacy
197 * devices won't operate well if fast DMA is disabled.
199 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
200 PCI_DEVICE_ID_INTEL_82371AB_0,
201 PCI_ANY_ID, PCI_ANY_ID, NULL);
203 pci_read_config_byte(dev, 0x76, &value1);
204 pci_read_config_byte(dev, 0x77, &value2);
205 if ((value1 & 0x80) || (value2 & 0x80))
206 errata.piix4.fdma = 1;
213 if (errata.piix4.bmisx)
214 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
215 "Bus master activity detection (BM-IDE) erratum enabled\n"));
216 if (errata.piix4.fdma)
217 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
218 "Type-F DMA livelock erratum (C3 disabled)\n"));
223 static int acpi_processor_errata(struct acpi_processor *pr)
226 struct pci_dev *dev = NULL;
235 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
236 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
239 result = acpi_processor_errata_piix4(dev);
246 /* --------------------------------------------------------------------------
247 Common ACPI processor functions
248 -------------------------------------------------------------------------- */
251 * _PDC is required for a BIOS-OS handshake for most of the newer
252 * ACPI processor features.
254 static int acpi_processor_set_pdc(struct acpi_processor *pr)
256 struct acpi_object_list *pdc_in = pr->pdc;
257 acpi_status status = AE_OK;
263 status = acpi_evaluate_object(pr->handle, "_PDC", pdc_in, NULL);
265 if (ACPI_FAILURE(status))
266 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
267 "Could not evaluate _PDC, using legacy perf. control...\n"));
272 /* --------------------------------------------------------------------------
274 -------------------------------------------------------------------------- */
276 static struct proc_dir_entry *acpi_processor_dir = NULL;
278 static int acpi_processor_info_seq_show(struct seq_file *seq, void *offset)
280 struct acpi_processor *pr = (struct acpi_processor *)seq->private;
286 seq_printf(seq, "processor id: %d\n"
288 "bus mastering control: %s\n"
289 "power management: %s\n"
290 "throttling control: %s\n"
291 "limit interface: %s\n",
294 pr->flags.bm_control ? "yes" : "no",
295 pr->flags.power ? "yes" : "no",
296 pr->flags.throttling ? "yes" : "no",
297 pr->flags.limit ? "yes" : "no");
303 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file)
305 return single_open(file, acpi_processor_info_seq_show,
309 static int acpi_processor_add_fs(struct acpi_device *device)
311 struct proc_dir_entry *entry = NULL;
314 if (!acpi_device_dir(device)) {
315 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
317 if (!acpi_device_dir(device))
320 acpi_device_dir(device)->owner = THIS_MODULE;
323 entry = create_proc_entry(ACPI_PROCESSOR_FILE_INFO,
324 S_IRUGO, acpi_device_dir(device));
328 entry->proc_fops = &acpi_processor_info_fops;
329 entry->data = acpi_driver_data(device);
330 entry->owner = THIS_MODULE;
333 /* 'throttling' [R/W] */
334 entry = create_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
335 S_IFREG | S_IRUGO | S_IWUSR,
336 acpi_device_dir(device));
340 entry->proc_fops = &acpi_processor_throttling_fops;
341 entry->data = acpi_driver_data(device);
342 entry->owner = THIS_MODULE;
346 entry = create_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
347 S_IFREG | S_IRUGO | S_IWUSR,
348 acpi_device_dir(device));
352 entry->proc_fops = &acpi_processor_limit_fops;
353 entry->data = acpi_driver_data(device);
354 entry->owner = THIS_MODULE;
360 static int acpi_processor_remove_fs(struct acpi_device *device)
363 if (acpi_device_dir(device)) {
364 remove_proc_entry(ACPI_PROCESSOR_FILE_INFO,
365 acpi_device_dir(device));
366 remove_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
367 acpi_device_dir(device));
368 remove_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
369 acpi_device_dir(device));
370 remove_proc_entry(acpi_device_bid(device), acpi_processor_dir);
371 acpi_device_dir(device) = NULL;
377 /* Use the acpiid in MADT to map cpus in case of SMP */
379 #define convert_acpiid_to_cpu(acpi_id) (-1)
383 #define arch_acpiid_to_apicid ia64_acpiid_to_sapicid
384 #define arch_cpu_to_apicid ia64_cpu_to_sapicid
385 #define ARCH_BAD_APICID (0xffff)
387 #define arch_acpiid_to_apicid x86_acpiid_to_apicid
388 #define arch_cpu_to_apicid x86_cpu_to_apicid
389 #define ARCH_BAD_APICID (0xff)
392 static int convert_acpiid_to_cpu(u8 acpi_id)
397 apic_id = arch_acpiid_to_apicid[acpi_id];
398 if (apic_id == ARCH_BAD_APICID)
401 for (i = 0; i < NR_CPUS; i++) {
402 if (arch_cpu_to_apicid[i] == apic_id)
409 /* --------------------------------------------------------------------------
411 -------------------------------------------------------------------------- */
413 static int acpi_processor_get_info(struct acpi_processor *pr)
415 acpi_status status = 0;
416 union acpi_object object = { 0 };
417 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
419 static int cpu0_initialized;
425 if (num_online_cpus() > 1)
428 acpi_processor_errata(pr);
431 * Check to see if we have bus mastering arbitration control. This
432 * is required for proper C3 usage (to maintain cache coherency).
434 if (acpi_fadt.V1_pm2_cnt_blk && acpi_fadt.pm2_cnt_len) {
435 pr->flags.bm_control = 1;
436 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
437 "Bus mastering arbitration control present\n"));
439 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
440 "No bus mastering arbitration control\n"));
443 * Evalute the processor object. Note that it is common on SMP to
444 * have the first (boot) processor with a valid PBLK address while
445 * all others have a NULL address.
447 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
448 if (ACPI_FAILURE(status)) {
449 printk(KERN_ERR PREFIX "Evaluating processor object\n");
454 * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
455 * >>> 'acpi_get_processor_id(acpi_id, &id)' in arch/xxx/acpi.c
457 pr->acpi_id = object.processor.proc_id;
459 cpu_index = convert_acpiid_to_cpu(pr->acpi_id);
461 /* Handle UP system running SMP kernel, with no LAPIC in MADT */
462 if (!cpu0_initialized && (cpu_index == -1) &&
463 (num_online_cpus() == 1)) {
467 cpu0_initialized = 1;
472 * Extra Processor objects may be enumerated on MP systems with
473 * less than the max # of CPUs. They should be ignored _iff
474 * they are physically not present.
476 if (cpu_index == -1) {
478 (acpi_processor_hotadd_init(pr->handle, &pr->id))) {
479 printk(KERN_ERR PREFIX
480 "Getting cpuindex for acpiid 0x%x\n",
486 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
489 if (!object.processor.pblk_address)
490 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
491 else if (object.processor.pblk_length != 6)
492 printk(KERN_ERR PREFIX "Invalid PBLK length [%d]\n",
493 object.processor.pblk_length);
495 pr->throttling.address = object.processor.pblk_address;
496 pr->throttling.duty_offset = acpi_fadt.duty_offset;
497 pr->throttling.duty_width = acpi_fadt.duty_width;
499 pr->pblk = object.processor.pblk_address;
502 * We don't care about error returns - we just try to mark
503 * these reserved so that nobody else is confused into thinking
504 * that this region might be unused..
506 * (In particular, allocating the IO range for Cardbus)
508 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
511 #ifdef CONFIG_CPU_FREQ
512 acpi_processor_ppc_has_changed(pr);
514 acpi_processor_get_throttling_info(pr);
515 acpi_processor_get_limit_info(pr);
520 static void *processor_device_array[NR_CPUS];
522 static int acpi_processor_start(struct acpi_device *device)
525 acpi_status status = AE_OK;
526 struct acpi_processor *pr;
529 pr = acpi_driver_data(device);
531 result = acpi_processor_get_info(pr);
533 /* Processor is physically not present */
537 BUG_ON((pr->id >= NR_CPUS) || (pr->id < 0));
541 * ACPI id of processors can be reported wrongly by the BIOS.
542 * Don't trust it blindly
544 if (processor_device_array[pr->id] != NULL &&
545 processor_device_array[pr->id] != (void *)device) {
546 printk(KERN_WARNING "BIOS reported wrong ACPI id"
547 "for the processor\n");
550 processor_device_array[pr->id] = (void *)device;
552 processors[pr->id] = pr;
554 result = acpi_processor_add_fs(device);
558 status = acpi_install_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
559 acpi_processor_notify, pr);
561 /* _PDC call should be done before doing anything else (if reqd.). */
562 arch_acpi_processor_init_pdc(pr);
563 acpi_processor_set_pdc(pr);
565 acpi_processor_power_init(pr, device);
567 if (pr->flags.throttling) {
568 printk(KERN_INFO PREFIX "%s [%s] (supports",
569 acpi_device_name(device), acpi_device_bid(device));
570 printk(" %d throttling states", pr->throttling.state_count);
579 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
581 struct acpi_processor *pr = (struct acpi_processor *)data;
582 struct acpi_device *device = NULL;
588 if (acpi_bus_get_device(pr->handle, &device))
592 case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
593 acpi_processor_ppc_has_changed(pr);
594 acpi_bus_generate_event(device, event,
595 pr->performance_platform_limit);
597 case ACPI_PROCESSOR_NOTIFY_POWER:
598 acpi_processor_cst_has_changed(pr);
599 acpi_bus_generate_event(device, event, 0);
602 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
603 "Unsupported event [0x%x]\n", event));
610 static int acpi_processor_add(struct acpi_device *device)
612 struct acpi_processor *pr = NULL;
618 pr = kmalloc(sizeof(struct acpi_processor), GFP_KERNEL);
621 memset(pr, 0, sizeof(struct acpi_processor));
623 pr->handle = device->handle;
624 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
625 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
626 acpi_driver_data(device) = pr;
631 static int acpi_processor_remove(struct acpi_device *device, int type)
633 acpi_status status = AE_OK;
634 struct acpi_processor *pr = NULL;
637 if (!device || !acpi_driver_data(device))
640 pr = (struct acpi_processor *)acpi_driver_data(device);
642 if (pr->id >= NR_CPUS) {
647 if (type == ACPI_BUS_REMOVAL_EJECT) {
648 if (acpi_processor_handle_eject(pr))
652 acpi_processor_power_exit(pr, device);
654 status = acpi_remove_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
655 acpi_processor_notify);
657 acpi_processor_remove_fs(device);
659 processors[pr->id] = NULL;
666 #ifdef CONFIG_ACPI_HOTPLUG_CPU
667 /****************************************************************************
668 * Acpi processor hotplug support *
669 ****************************************************************************/
671 static int is_processor_present(acpi_handle handle);
673 static int is_processor_present(acpi_handle handle)
676 unsigned long sta = 0;
679 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
680 if (ACPI_FAILURE(status) || !(sta & ACPI_STA_PRESENT)) {
681 ACPI_EXCEPTION((AE_INFO, status, "Processor Device is not present"));
688 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
691 struct acpi_device *pdev;
692 struct acpi_processor *pr;
695 if (acpi_get_parent(handle, &phandle)) {
699 if (acpi_bus_get_device(phandle, &pdev)) {
703 if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
707 acpi_bus_start(*device);
709 pr = acpi_driver_data(*device);
713 if ((pr->id >= 0) && (pr->id < NR_CPUS)) {
714 kobject_uevent(&(*device)->kobj, KOBJ_ONLINE);
720 acpi_processor_hotplug_notify(acpi_handle handle, u32 event, void *data)
722 struct acpi_processor *pr;
723 struct acpi_device *device = NULL;
728 case ACPI_NOTIFY_BUS_CHECK:
729 case ACPI_NOTIFY_DEVICE_CHECK:
730 printk("Processor driver received %s event\n",
731 (event == ACPI_NOTIFY_BUS_CHECK) ?
732 "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");
734 if (!is_processor_present(handle))
737 if (acpi_bus_get_device(handle, &device)) {
738 result = acpi_processor_device_add(handle, &device);
740 printk(KERN_ERR PREFIX
741 "Unable to add the device\n");
745 pr = acpi_driver_data(device);
747 printk(KERN_ERR PREFIX "Driver data is NULL\n");
751 if (pr->id >= 0 && (pr->id < NR_CPUS)) {
752 kobject_uevent(&device->kobj, KOBJ_OFFLINE);
756 result = acpi_processor_start(device);
757 if ((!result) && ((pr->id >= 0) && (pr->id < NR_CPUS))) {
758 kobject_uevent(&device->kobj, KOBJ_ONLINE);
760 printk(KERN_ERR PREFIX "Device [%s] failed to start\n",
761 acpi_device_bid(device));
764 case ACPI_NOTIFY_EJECT_REQUEST:
765 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
766 "received ACPI_NOTIFY_EJECT_REQUEST\n"));
768 if (acpi_bus_get_device(handle, &device)) {
769 printk(KERN_ERR PREFIX
770 "Device don't exist, dropping EJECT\n");
773 pr = acpi_driver_data(device);
775 printk(KERN_ERR PREFIX
776 "Driver data is NULL, dropping EJECT\n");
780 if ((pr->id < NR_CPUS) && (cpu_present(pr->id)))
781 kobject_uevent(&device->kobj, KOBJ_OFFLINE);
784 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
785 "Unsupported event [0x%x]\n", event));
793 processor_walk_namespace_cb(acpi_handle handle,
794 u32 lvl, void *context, void **rv)
797 int *action = context;
798 acpi_object_type type = 0;
800 status = acpi_get_type(handle, &type);
801 if (ACPI_FAILURE(status))
804 if (type != ACPI_TYPE_PROCESSOR)
808 case INSTALL_NOTIFY_HANDLER:
809 acpi_install_notify_handler(handle,
811 acpi_processor_hotplug_notify,
814 case UNINSTALL_NOTIFY_HANDLER:
815 acpi_remove_notify_handler(handle,
817 acpi_processor_hotplug_notify);
826 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
829 if (!is_processor_present(handle)) {
833 if (acpi_map_lsapic(handle, p_cpu))
836 if (arch_register_cpu(*p_cpu)) {
837 acpi_unmap_lsapic(*p_cpu);
844 static int acpi_processor_handle_eject(struct acpi_processor *pr)
846 if (cpu_online(pr->id)) {
849 arch_unregister_cpu(pr->id);
850 acpi_unmap_lsapic(pr->id);
854 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
858 static int acpi_processor_handle_eject(struct acpi_processor *pr)
865 void acpi_processor_install_hotplug_notify(void)
867 #ifdef CONFIG_ACPI_HOTPLUG_CPU
868 int action = INSTALL_NOTIFY_HANDLER;
869 acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
872 processor_walk_namespace_cb, &action, NULL);
877 void acpi_processor_uninstall_hotplug_notify(void)
879 #ifdef CONFIG_ACPI_HOTPLUG_CPU
880 int action = UNINSTALL_NOTIFY_HANDLER;
881 acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
884 processor_walk_namespace_cb, &action, NULL);
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
894 static int __init acpi_processor_init(void)
899 memset(&processors, 0, sizeof(processors));
900 memset(&errata, 0, sizeof(errata));
902 acpi_processor_dir = proc_mkdir(ACPI_PROCESSOR_CLASS, acpi_root_dir);
903 if (!acpi_processor_dir)
905 acpi_processor_dir->owner = THIS_MODULE;
907 result = acpi_bus_register_driver(&acpi_processor_driver);
909 remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
913 acpi_processor_install_hotplug_notify();
915 acpi_thermal_cpufreq_init();
917 acpi_processor_ppc_init();
922 static void __exit acpi_processor_exit(void)
925 acpi_processor_ppc_exit();
927 acpi_thermal_cpufreq_exit();
929 acpi_processor_uninstall_hotplug_notify();
931 acpi_bus_unregister_driver(&acpi_processor_driver);
933 remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
938 module_init(acpi_processor_init);
939 module_exit(acpi_processor_exit);
941 EXPORT_SYMBOL(acpi_processor_set_thermal_limit);
943 MODULE_ALIAS("processor");