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
acpi_processor_errata_piix4(struct pci_dev * dev)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
acpi_processor_errata(void)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
acpi_map_cpu(acpi_handle handle,phys_cpuid_t physid,u32 acpi_id,int * pcpu)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
acpi_unmap_cpu(int cpu)173 int __weak acpi_unmap_cpu(int cpu)
174 {
175 return -ENODEV;
176 }
177
arch_register_cpu(int cpu)178 int __weak arch_register_cpu(int cpu)
179 {
180 return -ENODEV;
181 }
182
arch_unregister_cpu(int cpu)183 void __weak arch_unregister_cpu(int cpu) {}
184
acpi_processor_hotadd_init(struct acpi_processor * pr)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
acpi_processor_hotadd_init(struct acpi_processor * pr)225 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
226 {
227 return -ENODEV;
228 }
229 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
230
acpi_processor_get_info(struct acpi_device * device)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 if (pr->acpi_id == 0xff)
285 dev_info_once(&device->dev,
286 "Entry not well-defined, consider updating BIOS\n");
287 else
288 dev_err(&device->dev,
289 "Failed to get unique processor _UID (0x%x)\n",
290 pr->acpi_id);
291 return -ENODEV;
292 }
293
294 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
295 pr->acpi_id);
296 if (invalid_phys_cpuid(pr->phys_id))
297 acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
298
299 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
300 if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
301 cpu0_initialized = 1;
302 /*
303 * Handle UP system running SMP kernel, with no CPU
304 * entry in MADT
305 */
306 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
307 pr->id = 0;
308 }
309
310 /*
311 * Extra Processor objects may be enumerated on MP systems with
312 * less than the max # of CPUs. They should be ignored _iff
313 * they are physically not present.
314 *
315 * NOTE: Even if the processor has a cpuid, it may not be present
316 * because cpuid <-> apicid mapping is persistent now.
317 */
318 if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
319 int ret = acpi_processor_hotadd_init(pr);
320 if (ret)
321 return ret;
322 }
323
324 /*
325 * On some boxes several processors use the same processor bus id.
326 * But they are located in different scope. For example:
327 * \_SB.SCK0.CPU0
328 * \_SB.SCK1.CPU0
329 * Rename the processor device bus id. And the new bus id will be
330 * generated as the following format:
331 * CPU+CPU ID.
332 */
333 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
334 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
335 pr->acpi_id));
336
337 if (!object.processor.pblk_address)
338 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
339 else if (object.processor.pblk_length != 6)
340 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
341 object.processor.pblk_length);
342 else {
343 pr->throttling.address = object.processor.pblk_address;
344 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
345 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
346
347 pr->pblk = object.processor.pblk_address;
348 }
349
350 /*
351 * If ACPI describes a slot number for this CPU, we can use it to
352 * ensure we get the right value in the "physical id" field
353 * of /proc/cpuinfo
354 */
355 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
356 if (ACPI_SUCCESS(status))
357 arch_fix_phys_package_id(pr->id, value);
358
359 return 0;
360 }
361
362 /*
363 * Do not put anything in here which needs the core to be online.
364 * For example MSR access or setting up things which check for cpuinfo_x86
365 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
366 * Such things have to be put in and set up by the processor driver's .probe().
367 */
368 static DEFINE_PER_CPU(void *, processor_device_array);
369
acpi_processor_add(struct acpi_device * device,const struct acpi_device_id * id)370 static int acpi_processor_add(struct acpi_device *device,
371 const struct acpi_device_id *id)
372 {
373 struct acpi_processor *pr;
374 struct device *dev;
375 int result = 0;
376
377 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
378 if (!pr)
379 return -ENOMEM;
380
381 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
382 result = -ENOMEM;
383 goto err_free_pr;
384 }
385
386 pr->handle = device->handle;
387 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
388 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
389 device->driver_data = pr;
390
391 result = acpi_processor_get_info(device);
392 if (result) /* Processor is not physically present or unavailable */
393 return 0;
394
395 BUG_ON(pr->id >= nr_cpu_ids);
396
397 /*
398 * Buggy BIOS check.
399 * ACPI id of processors can be reported wrongly by the BIOS.
400 * Don't trust it blindly
401 */
402 if (per_cpu(processor_device_array, pr->id) != NULL &&
403 per_cpu(processor_device_array, pr->id) != device) {
404 dev_warn(&device->dev,
405 "BIOS reported wrong ACPI id %d for the processor\n",
406 pr->id);
407 /* Give up, but do not abort the namespace scan. */
408 goto err;
409 }
410 /*
411 * processor_device_array is not cleared on errors to allow buggy BIOS
412 * checks.
413 */
414 per_cpu(processor_device_array, pr->id) = device;
415 per_cpu(processors, pr->id) = pr;
416
417 dev = get_cpu_device(pr->id);
418 if (!dev) {
419 result = -ENODEV;
420 goto err;
421 }
422
423 result = acpi_bind_one(dev, device);
424 if (result)
425 goto err;
426
427 pr->dev = dev;
428
429 /* Trigger the processor driver's .probe() if present. */
430 if (device_attach(dev) >= 0)
431 return 1;
432
433 dev_err(dev, "Processor driver could not be attached\n");
434 acpi_unbind_one(dev);
435
436 err:
437 free_cpumask_var(pr->throttling.shared_cpu_map);
438 device->driver_data = NULL;
439 per_cpu(processors, pr->id) = NULL;
440 err_free_pr:
441 kfree(pr);
442 return result;
443 }
444
445 #ifdef CONFIG_ACPI_HOTPLUG_CPU
446 /* --------------------------------------------------------------------------
447 Removal
448 -------------------------------------------------------------------------- */
449
acpi_processor_remove(struct acpi_device * device)450 static void acpi_processor_remove(struct acpi_device *device)
451 {
452 struct acpi_processor *pr;
453
454 if (!device || !acpi_driver_data(device))
455 return;
456
457 pr = acpi_driver_data(device);
458 if (pr->id >= nr_cpu_ids)
459 goto out;
460
461 /*
462 * The only reason why we ever get here is CPU hot-removal. The CPU is
463 * already offline and the ACPI device removal locking prevents it from
464 * being put back online at this point.
465 *
466 * Unbind the driver from the processor device and detach it from the
467 * ACPI companion object.
468 */
469 device_release_driver(pr->dev);
470 acpi_unbind_one(pr->dev);
471
472 /* Clean up. */
473 per_cpu(processor_device_array, pr->id) = NULL;
474 per_cpu(processors, pr->id) = NULL;
475
476 cpu_maps_update_begin();
477 cpu_hotplug_begin();
478
479 /* Remove the CPU. */
480 arch_unregister_cpu(pr->id);
481 acpi_unmap_cpu(pr->id);
482
483 cpu_hotplug_done();
484 cpu_maps_update_done();
485
486 try_offline_node(cpu_to_node(pr->id));
487
488 out:
489 free_cpumask_var(pr->throttling.shared_cpu_map);
490 kfree(pr);
491 }
492 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
493
494 #ifdef CONFIG_X86
495 static bool acpi_hwp_native_thermal_lvt_set;
acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,u32 lvl,void * context,void ** rv)496 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
497 u32 lvl,
498 void *context,
499 void **rv)
500 {
501 u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
502 u32 capbuf[2];
503 struct acpi_osc_context osc_context = {
504 .uuid_str = sb_uuid_str,
505 .rev = 1,
506 .cap.length = 8,
507 .cap.pointer = capbuf,
508 };
509
510 if (acpi_hwp_native_thermal_lvt_set)
511 return AE_CTRL_TERMINATE;
512
513 capbuf[0] = 0x0000;
514 capbuf[1] = 0x1000; /* set bit 12 */
515
516 if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
517 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
518 u32 *capbuf_ret = osc_context.ret.pointer;
519
520 if (capbuf_ret[1] & 0x1000) {
521 acpi_handle_info(handle,
522 "_OSC native thermal LVT Acked\n");
523 acpi_hwp_native_thermal_lvt_set = true;
524 }
525 }
526 kfree(osc_context.ret.pointer);
527 }
528
529 return AE_OK;
530 }
531
acpi_early_processor_osc(void)532 void __init acpi_early_processor_osc(void)
533 {
534 if (boot_cpu_has(X86_FEATURE_HWP)) {
535 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
536 ACPI_UINT32_MAX,
537 acpi_hwp_native_thermal_lvt_osc,
538 NULL, NULL, NULL);
539 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
540 acpi_hwp_native_thermal_lvt_osc,
541 NULL, NULL);
542 }
543 }
544 #endif
545
546 /*
547 * The following ACPI IDs are known to be suitable for representing as
548 * processor devices.
549 */
550 static const struct acpi_device_id processor_device_ids[] = {
551
552 { ACPI_PROCESSOR_OBJECT_HID, },
553 { ACPI_PROCESSOR_DEVICE_HID, },
554
555 { }
556 };
557
558 static struct acpi_scan_handler processor_handler = {
559 .ids = processor_device_ids,
560 .attach = acpi_processor_add,
561 #ifdef CONFIG_ACPI_HOTPLUG_CPU
562 .detach = acpi_processor_remove,
563 #endif
564 .hotplug = {
565 .enabled = true,
566 },
567 };
568
acpi_processor_container_attach(struct acpi_device * dev,const struct acpi_device_id * id)569 static int acpi_processor_container_attach(struct acpi_device *dev,
570 const struct acpi_device_id *id)
571 {
572 return 1;
573 }
574
575 static const struct acpi_device_id processor_container_ids[] = {
576 { ACPI_PROCESSOR_CONTAINER_HID, },
577 { }
578 };
579
580 static struct acpi_scan_handler processor_container_handler = {
581 .ids = processor_container_ids,
582 .attach = acpi_processor_container_attach,
583 };
584
585 /* The number of the unique processor IDs */
586 static int nr_unique_ids __initdata;
587
588 /* The number of the duplicate processor IDs */
589 static int nr_duplicate_ids;
590
591 /* Used to store the unique processor IDs */
592 static int unique_processor_ids[] __initdata = {
593 [0 ... NR_CPUS - 1] = -1,
594 };
595
596 /* Used to store the duplicate processor IDs */
597 static int duplicate_processor_ids[] = {
598 [0 ... NR_CPUS - 1] = -1,
599 };
600
processor_validated_ids_update(int proc_id)601 static void __init processor_validated_ids_update(int proc_id)
602 {
603 int i;
604
605 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
606 return;
607
608 /*
609 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
610 * already in the IDs, do nothing.
611 */
612 for (i = 0; i < nr_duplicate_ids; i++) {
613 if (duplicate_processor_ids[i] == proc_id)
614 return;
615 }
616
617 /*
618 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
619 * the IDs, put it in the duplicate IDs.
620 */
621 for (i = 0; i < nr_unique_ids; i++) {
622 if (unique_processor_ids[i] == proc_id) {
623 duplicate_processor_ids[nr_duplicate_ids] = proc_id;
624 nr_duplicate_ids++;
625 return;
626 }
627 }
628
629 /*
630 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
631 */
632 unique_processor_ids[nr_unique_ids] = proc_id;
633 nr_unique_ids++;
634 }
635
acpi_processor_ids_walk(acpi_handle handle,u32 lvl,void * context,void ** rv)636 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
637 u32 lvl,
638 void *context,
639 void **rv)
640 {
641 acpi_status status;
642 acpi_object_type acpi_type;
643 unsigned long long uid;
644 union acpi_object object = { 0 };
645 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
646
647 status = acpi_get_type(handle, &acpi_type);
648 if (ACPI_FAILURE(status))
649 return status;
650
651 switch (acpi_type) {
652 case ACPI_TYPE_PROCESSOR:
653 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
654 if (ACPI_FAILURE(status))
655 goto err;
656 uid = object.processor.proc_id;
657 break;
658
659 case ACPI_TYPE_DEVICE:
660 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
661 if (ACPI_FAILURE(status))
662 goto err;
663 break;
664 default:
665 goto err;
666 }
667
668 processor_validated_ids_update(uid);
669 return AE_OK;
670
671 err:
672 /* Exit on error, but don't abort the namespace walk */
673 acpi_handle_info(handle, "Invalid processor object\n");
674 return AE_OK;
675
676 }
677
acpi_processor_check_duplicates(void)678 static 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
acpi_duplicate_processor_id(int proc_id)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
acpi_processor_init(void)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 }
710