Merge remote-tracking branches 'asoc/topic/sta529', 'asoc/topic/sti', 'asoc/topic...
[sfrench/cifs-2.6.git] / drivers / acpi / acpi_processor.c
1 /*
2  * acpi_processor.c - ACPI processor enumeration support
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  * Copyright (C) 2013, Intel Corporation
9  *                     Rafael J. Wysocki <rafael.j.wysocki@intel.com>
10  *
11  * This program is free software; you can redistribute it and/or modify it
12  * under the terms of the GNU General Public License version 2 as published
13  * by the Free Software Foundation.
14  */
15
16 #include <linux/acpi.h>
17 #include <linux/device.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/pci.h>
21
22 #include <acpi/processor.h>
23
24 #include <asm/cpu.h>
25
26 #include "internal.h"
27
28 #define _COMPONENT      ACPI_PROCESSOR_COMPONENT
29
30 ACPI_MODULE_NAME("processor");
31
32 DEFINE_PER_CPU(struct acpi_processor *, processors);
33 EXPORT_PER_CPU_SYMBOL(processors);
34
35 /* --------------------------------------------------------------------------
36                                 Errata Handling
37    -------------------------------------------------------------------------- */
38
39 struct acpi_processor_errata errata __read_mostly;
40 EXPORT_SYMBOL_GPL(errata);
41
42 static int acpi_processor_errata_piix4(struct pci_dev *dev)
43 {
44         u8 value1 = 0;
45         u8 value2 = 0;
46
47
48         if (!dev)
49                 return -EINVAL;
50
51         /*
52          * Note that 'dev' references the PIIX4 ACPI Controller.
53          */
54
55         switch (dev->revision) {
56         case 0:
57                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
58                 break;
59         case 1:
60                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
61                 break;
62         case 2:
63                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
64                 break;
65         case 3:
66                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
67                 break;
68         default:
69                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
70                 break;
71         }
72
73         switch (dev->revision) {
74
75         case 0:         /* PIIX4 A-step */
76         case 1:         /* PIIX4 B-step */
77                 /*
78                  * See specification changes #13 ("Manual Throttle Duty Cycle")
79                  * and #14 ("Enabling and Disabling Manual Throttle"), plus
80                  * erratum #5 ("STPCLK# Deassertion Time") from the January
81                  * 2002 PIIX4 specification update.  Applies to only older
82                  * PIIX4 models.
83                  */
84                 errata.piix4.throttle = 1;
85
86         case 2:         /* PIIX4E */
87         case 3:         /* PIIX4M */
88                 /*
89                  * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
90                  * Livelock") from the January 2002 PIIX4 specification update.
91                  * Applies to all PIIX4 models.
92                  */
93
94                 /*
95                  * BM-IDE
96                  * ------
97                  * Find the PIIX4 IDE Controller and get the Bus Master IDE
98                  * Status register address.  We'll use this later to read
99                  * each IDE controller's DMA status to make sure we catch all
100                  * DMA activity.
101                  */
102                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
103                                      PCI_DEVICE_ID_INTEL_82371AB,
104                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
105                 if (dev) {
106                         errata.piix4.bmisx = pci_resource_start(dev, 4);
107                         pci_dev_put(dev);
108                 }
109
110                 /*
111                  * Type-F DMA
112                  * ----------
113                  * Find the PIIX4 ISA Controller and read the Motherboard
114                  * DMA controller's status to see if Type-F (Fast) DMA mode
115                  * is enabled (bit 7) on either channel.  Note that we'll
116                  * disable C3 support if this is enabled, as some legacy
117                  * devices won't operate well if fast DMA is disabled.
118                  */
119                 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
120                                      PCI_DEVICE_ID_INTEL_82371AB_0,
121                                      PCI_ANY_ID, PCI_ANY_ID, NULL);
122                 if (dev) {
123                         pci_read_config_byte(dev, 0x76, &value1);
124                         pci_read_config_byte(dev, 0x77, &value2);
125                         if ((value1 & 0x80) || (value2 & 0x80))
126                                 errata.piix4.fdma = 1;
127                         pci_dev_put(dev);
128                 }
129
130                 break;
131         }
132
133         if (errata.piix4.bmisx)
134                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
135                                   "Bus master activity detection (BM-IDE) erratum enabled\n"));
136         if (errata.piix4.fdma)
137                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
138                                   "Type-F DMA livelock erratum (C3 disabled)\n"));
139
140         return 0;
141 }
142
143 static int acpi_processor_errata(void)
144 {
145         int result = 0;
146         struct pci_dev *dev = NULL;
147
148         /*
149          * PIIX4
150          */
151         dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
152                              PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
153                              PCI_ANY_ID, NULL);
154         if (dev) {
155                 result = acpi_processor_errata_piix4(dev);
156                 pci_dev_put(dev);
157         }
158
159         return result;
160 }
161
162 /* --------------------------------------------------------------------------
163                                 Initialization
164    -------------------------------------------------------------------------- */
165
166 #ifdef CONFIG_ACPI_HOTPLUG_CPU
167 int __weak acpi_map_cpu(acpi_handle handle,
168                 phys_cpuid_t physid, u32 acpi_id, int *pcpu)
169 {
170         return -ENODEV;
171 }
172
173 int __weak acpi_unmap_cpu(int cpu)
174 {
175         return -ENODEV;
176 }
177
178 int __weak arch_register_cpu(int cpu)
179 {
180         return -ENODEV;
181 }
182
183 void __weak arch_unregister_cpu(int cpu) {}
184
185 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
186 {
187         unsigned long long sta;
188         acpi_status status;
189         int ret;
190
191         if (invalid_phys_cpuid(pr->phys_id))
192                 return -ENODEV;
193
194         status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
195         if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
196                 return -ENODEV;
197
198         cpu_maps_update_begin();
199         cpu_hotplug_begin();
200
201         ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
202         if (ret)
203                 goto out;
204
205         ret = arch_register_cpu(pr->id);
206         if (ret) {
207                 acpi_unmap_cpu(pr->id);
208                 goto out;
209         }
210
211         /*
212          * CPU got hot-added, but cpu_data is not initialized yet.  Set a flag
213          * to delay cpu_idle/throttling initialization and do it when the CPU
214          * gets online for the first time.
215          */
216         pr_info("CPU%d has been hot-added\n", pr->id);
217         pr->flags.need_hotplug_init = 1;
218
219 out:
220         cpu_hotplug_done();
221         cpu_maps_update_done();
222         return ret;
223 }
224 #else
225 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
226 {
227         return -ENODEV;
228 }
229 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
230
231 static int acpi_processor_get_info(struct acpi_device *device)
232 {
233         union acpi_object object = { 0 };
234         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
235         struct acpi_processor *pr = acpi_driver_data(device);
236         int device_declaration = 0;
237         acpi_status status = AE_OK;
238         static int cpu0_initialized;
239         unsigned long long value;
240
241         acpi_processor_errata();
242
243         /*
244          * Check to see if we have bus mastering arbitration control.  This
245          * is required for proper C3 usage (to maintain cache coherency).
246          */
247         if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
248                 pr->flags.bm_control = 1;
249                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
250                                   "Bus mastering arbitration control present\n"));
251         } else
252                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
253                                   "No bus mastering arbitration control\n"));
254
255         if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
256                 /* Declared with "Processor" statement; match ProcessorID */
257                 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
258                 if (ACPI_FAILURE(status)) {
259                         dev_err(&device->dev,
260                                 "Failed to evaluate processor object (0x%x)\n",
261                                 status);
262                         return -ENODEV;
263                 }
264
265                 pr->acpi_id = object.processor.proc_id;
266         } else {
267                 /*
268                  * Declared with "Device" statement; match _UID.
269                  * Note that we don't handle string _UIDs yet.
270                  */
271                 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
272                                                 NULL, &value);
273                 if (ACPI_FAILURE(status)) {
274                         dev_err(&device->dev,
275                                 "Failed to evaluate processor _UID (0x%x)\n",
276                                 status);
277                         return -ENODEV;
278                 }
279                 device_declaration = 1;
280                 pr->acpi_id = value;
281         }
282
283         if (acpi_duplicate_processor_id(pr->acpi_id)) {
284                 dev_err(&device->dev,
285                         "Failed to get unique processor _UID (0x%x)\n",
286                         pr->acpi_id);
287                 return -ENODEV;
288         }
289
290         pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
291                                         pr->acpi_id);
292         if (invalid_phys_cpuid(pr->phys_id))
293                 acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
294
295         pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
296         if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
297                 cpu0_initialized = 1;
298                 /*
299                  * Handle UP system running SMP kernel, with no CPU
300                  * entry in MADT
301                  */
302                 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
303                         pr->id = 0;
304         }
305
306         /*
307          *  Extra Processor objects may be enumerated on MP systems with
308          *  less than the max # of CPUs. They should be ignored _iff
309          *  they are physically not present.
310          *
311          *  NOTE: Even if the processor has a cpuid, it may not be present
312          *  because cpuid <-> apicid mapping is persistent now.
313          */
314         if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
315                 int ret = acpi_processor_hotadd_init(pr);
316                 if (ret)
317                         return ret;
318         }
319
320         /*
321          * On some boxes several processors use the same processor bus id.
322          * But they are located in different scope. For example:
323          * \_SB.SCK0.CPU0
324          * \_SB.SCK1.CPU0
325          * Rename the processor device bus id. And the new bus id will be
326          * generated as the following format:
327          * CPU+CPU ID.
328          */
329         sprintf(acpi_device_bid(device), "CPU%X", pr->id);
330         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
331                           pr->acpi_id));
332
333         if (!object.processor.pblk_address)
334                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
335         else if (object.processor.pblk_length != 6)
336                 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
337                             object.processor.pblk_length);
338         else {
339                 pr->throttling.address = object.processor.pblk_address;
340                 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
341                 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
342
343                 pr->pblk = object.processor.pblk_address;
344         }
345
346         /*
347          * If ACPI describes a slot number for this CPU, we can use it to
348          * ensure we get the right value in the "physical id" field
349          * of /proc/cpuinfo
350          */
351         status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
352         if (ACPI_SUCCESS(status))
353                 arch_fix_phys_package_id(pr->id, value);
354
355         return 0;
356 }
357
358 /*
359  * Do not put anything in here which needs the core to be online.
360  * For example MSR access or setting up things which check for cpuinfo_x86
361  * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
362  * Such things have to be put in and set up by the processor driver's .probe().
363  */
364 static DEFINE_PER_CPU(void *, processor_device_array);
365
366 static int acpi_processor_add(struct acpi_device *device,
367                                         const struct acpi_device_id *id)
368 {
369         struct acpi_processor *pr;
370         struct device *dev;
371         int result = 0;
372
373         pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
374         if (!pr)
375                 return -ENOMEM;
376
377         if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
378                 result = -ENOMEM;
379                 goto err_free_pr;
380         }
381
382         pr->handle = device->handle;
383         strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
384         strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
385         device->driver_data = pr;
386
387         result = acpi_processor_get_info(device);
388         if (result) /* Processor is not physically present or unavailable */
389                 return 0;
390
391 #ifdef CONFIG_SMP
392         if (pr->id >= setup_max_cpus && pr->id != 0)
393                 return 0;
394 #endif
395
396         BUG_ON(pr->id >= nr_cpu_ids);
397
398         /*
399          * Buggy BIOS check.
400          * ACPI id of processors can be reported wrongly by the BIOS.
401          * Don't trust it blindly
402          */
403         if (per_cpu(processor_device_array, pr->id) != NULL &&
404             per_cpu(processor_device_array, pr->id) != device) {
405                 dev_warn(&device->dev,
406                         "BIOS reported wrong ACPI id %d for the processor\n",
407                         pr->id);
408                 /* Give up, but do not abort the namespace scan. */
409                 goto err;
410         }
411         /*
412          * processor_device_array is not cleared on errors to allow buggy BIOS
413          * checks.
414          */
415         per_cpu(processor_device_array, pr->id) = device;
416         per_cpu(processors, pr->id) = pr;
417
418         dev = get_cpu_device(pr->id);
419         if (!dev) {
420                 result = -ENODEV;
421                 goto err;
422         }
423
424         result = acpi_bind_one(dev, device);
425         if (result)
426                 goto err;
427
428         pr->dev = dev;
429
430         /* Trigger the processor driver's .probe() if present. */
431         if (device_attach(dev) >= 0)
432                 return 1;
433
434         dev_err(dev, "Processor driver could not be attached\n");
435         acpi_unbind_one(dev);
436
437  err:
438         free_cpumask_var(pr->throttling.shared_cpu_map);
439         device->driver_data = NULL;
440         per_cpu(processors, pr->id) = NULL;
441  err_free_pr:
442         kfree(pr);
443         return result;
444 }
445
446 #ifdef CONFIG_ACPI_HOTPLUG_CPU
447 /* --------------------------------------------------------------------------
448                                     Removal
449    -------------------------------------------------------------------------- */
450
451 static void acpi_processor_remove(struct acpi_device *device)
452 {
453         struct acpi_processor *pr;
454
455         if (!device || !acpi_driver_data(device))
456                 return;
457
458         pr = acpi_driver_data(device);
459         if (pr->id >= nr_cpu_ids)
460                 goto out;
461
462         /*
463          * The only reason why we ever get here is CPU hot-removal.  The CPU is
464          * already offline and the ACPI device removal locking prevents it from
465          * being put back online at this point.
466          *
467          * Unbind the driver from the processor device and detach it from the
468          * ACPI companion object.
469          */
470         device_release_driver(pr->dev);
471         acpi_unbind_one(pr->dev);
472
473         /* Clean up. */
474         per_cpu(processor_device_array, pr->id) = NULL;
475         per_cpu(processors, pr->id) = NULL;
476
477         cpu_maps_update_begin();
478         cpu_hotplug_begin();
479
480         /* Remove the CPU. */
481         arch_unregister_cpu(pr->id);
482         acpi_unmap_cpu(pr->id);
483
484         cpu_hotplug_done();
485         cpu_maps_update_done();
486
487         try_offline_node(cpu_to_node(pr->id));
488
489  out:
490         free_cpumask_var(pr->throttling.shared_cpu_map);
491         kfree(pr);
492 }
493 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
494
495 #ifdef CONFIG_X86
496 static bool acpi_hwp_native_thermal_lvt_set;
497 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
498                                                           u32 lvl,
499                                                           void *context,
500                                                           void **rv)
501 {
502         u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
503         u32 capbuf[2];
504         struct acpi_osc_context osc_context = {
505                 .uuid_str = sb_uuid_str,
506                 .rev = 1,
507                 .cap.length = 8,
508                 .cap.pointer = capbuf,
509         };
510
511         if (acpi_hwp_native_thermal_lvt_set)
512                 return AE_CTRL_TERMINATE;
513
514         capbuf[0] = 0x0000;
515         capbuf[1] = 0x1000; /* set bit 12 */
516
517         if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
518                 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
519                         u32 *capbuf_ret = osc_context.ret.pointer;
520
521                         if (capbuf_ret[1] & 0x1000) {
522                                 acpi_handle_info(handle,
523                                         "_OSC native thermal LVT Acked\n");
524                                 acpi_hwp_native_thermal_lvt_set = true;
525                         }
526                 }
527                 kfree(osc_context.ret.pointer);
528         }
529
530         return AE_OK;
531 }
532
533 void __init acpi_early_processor_osc(void)
534 {
535         if (boot_cpu_has(X86_FEATURE_HWP)) {
536                 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
537                                     ACPI_UINT32_MAX,
538                                     acpi_hwp_native_thermal_lvt_osc,
539                                     NULL, NULL, NULL);
540                 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
541                                  acpi_hwp_native_thermal_lvt_osc,
542                                  NULL, NULL);
543         }
544 }
545 #endif
546
547 /*
548  * The following ACPI IDs are known to be suitable for representing as
549  * processor devices.
550  */
551 static const struct acpi_device_id processor_device_ids[] = {
552
553         { ACPI_PROCESSOR_OBJECT_HID, },
554         { ACPI_PROCESSOR_DEVICE_HID, },
555
556         { }
557 };
558
559 static struct acpi_scan_handler processor_handler = {
560         .ids = processor_device_ids,
561         .attach = acpi_processor_add,
562 #ifdef CONFIG_ACPI_HOTPLUG_CPU
563         .detach = acpi_processor_remove,
564 #endif
565         .hotplug = {
566                 .enabled = true,
567         },
568 };
569
570 static int acpi_processor_container_attach(struct acpi_device *dev,
571                                            const struct acpi_device_id *id)
572 {
573         return 1;
574 }
575
576 static const struct acpi_device_id processor_container_ids[] = {
577         { ACPI_PROCESSOR_CONTAINER_HID, },
578         { }
579 };
580
581 static struct acpi_scan_handler processor_container_handler = {
582         .ids = processor_container_ids,
583         .attach = acpi_processor_container_attach,
584 };
585
586 /* The number of the unique processor IDs */
587 static int nr_unique_ids __initdata;
588
589 /* The number of the duplicate processor IDs */
590 static int nr_duplicate_ids;
591
592 /* Used to store the unique processor IDs */
593 static int unique_processor_ids[] __initdata = {
594         [0 ... NR_CPUS - 1] = -1,
595 };
596
597 /* Used to store the duplicate processor IDs */
598 static int duplicate_processor_ids[] = {
599         [0 ... NR_CPUS - 1] = -1,
600 };
601
602 static void __init processor_validated_ids_update(int proc_id)
603 {
604         int i;
605
606         if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
607                 return;
608
609         /*
610          * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
611          * already in the IDs, do nothing.
612          */
613         for (i = 0; i < nr_duplicate_ids; i++) {
614                 if (duplicate_processor_ids[i] == proc_id)
615                         return;
616         }
617
618         /*
619          * Secondly, compare the proc_id with unique IDs, if the proc_id is in
620          * the IDs, put it in the duplicate IDs.
621          */
622         for (i = 0; i < nr_unique_ids; i++) {
623                 if (unique_processor_ids[i] == proc_id) {
624                         duplicate_processor_ids[nr_duplicate_ids] = proc_id;
625                         nr_duplicate_ids++;
626                         return;
627                 }
628         }
629
630         /*
631          * Lastly, the proc_id is a unique ID, put it in the unique IDs.
632          */
633         unique_processor_ids[nr_unique_ids] = proc_id;
634         nr_unique_ids++;
635 }
636
637 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
638                                                   u32 lvl,
639                                                   void *context,
640                                                   void **rv)
641 {
642         acpi_status status;
643         acpi_object_type acpi_type;
644         unsigned long long uid;
645         union acpi_object object = { 0 };
646         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
647
648         status = acpi_get_type(handle, &acpi_type);
649         if (ACPI_FAILURE(status))
650                 return false;
651
652         switch (acpi_type) {
653         case ACPI_TYPE_PROCESSOR:
654                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
655                 if (ACPI_FAILURE(status))
656                         goto err;
657                 uid = object.processor.proc_id;
658                 break;
659
660         case ACPI_TYPE_DEVICE:
661                 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
662                 if (ACPI_FAILURE(status))
663                         goto err;
664                 break;
665         default:
666                 goto err;
667         }
668
669         processor_validated_ids_update(uid);
670         return true;
671
672 err:
673         acpi_handle_info(handle, "Invalid processor object\n");
674         return false;
675
676 }
677
678 void __init acpi_processor_check_duplicates(void)
679 {
680         /* check the correctness for all processors in ACPI namespace */
681         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
682                                                 ACPI_UINT32_MAX,
683                                                 acpi_processor_ids_walk,
684                                                 NULL, NULL, NULL);
685         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
686                                                 NULL, NULL);
687 }
688
689 bool acpi_duplicate_processor_id(int proc_id)
690 {
691         int i;
692
693         /*
694          * compare the proc_id with duplicate IDs, if the proc_id is already
695          * in the duplicate IDs, return true, otherwise, return false.
696          */
697         for (i = 0; i < nr_duplicate_ids; i++) {
698                 if (duplicate_processor_ids[i] == proc_id)
699                         return true;
700         }
701         return false;
702 }
703
704 void __init acpi_processor_init(void)
705 {
706         acpi_processor_check_duplicates();
707         acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
708         acpi_scan_add_handler(&processor_container_handler);
709 }