xref: /openbmc/linux/drivers/acpi/acpi_processor.c (revision 4bb1e4e7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * acpi_processor.c - ACPI processor enumeration support
4  *
5  * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6  * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7  * Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
8  * Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9  * Copyright (C) 2013, Intel Corporation
10  *                     Rafael J. Wysocki <rafael.j.wysocki@intel.com>
11  */
12 
13 #include <linux/acpi.h>
14 #include <linux/device.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/pci.h>
18 
19 #include <acpi/processor.h>
20 
21 #include <asm/cpu.h>
22 
23 #include "internal.h"
24 
25 #define _COMPONENT	ACPI_PROCESSOR_COMPONENT
26 
27 ACPI_MODULE_NAME("processor");
28 
29 DEFINE_PER_CPU(struct acpi_processor *, processors);
30 EXPORT_PER_CPU_SYMBOL(processors);
31 
32 /* --------------------------------------------------------------------------
33                                 Errata Handling
34    -------------------------------------------------------------------------- */
35 
36 struct acpi_processor_errata errata __read_mostly;
37 EXPORT_SYMBOL_GPL(errata);
38 
39 static int acpi_processor_errata_piix4(struct pci_dev *dev)
40 {
41 	u8 value1 = 0;
42 	u8 value2 = 0;
43 
44 
45 	if (!dev)
46 		return -EINVAL;
47 
48 	/*
49 	 * Note that 'dev' references the PIIX4 ACPI Controller.
50 	 */
51 
52 	switch (dev->revision) {
53 	case 0:
54 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
55 		break;
56 	case 1:
57 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
58 		break;
59 	case 2:
60 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
61 		break;
62 	case 3:
63 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
64 		break;
65 	default:
66 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
67 		break;
68 	}
69 
70 	switch (dev->revision) {
71 
72 	case 0:		/* PIIX4 A-step */
73 	case 1:		/* PIIX4 B-step */
74 		/*
75 		 * See specification changes #13 ("Manual Throttle Duty Cycle")
76 		 * and #14 ("Enabling and Disabling Manual Throttle"), plus
77 		 * erratum #5 ("STPCLK# Deassertion Time") from the January
78 		 * 2002 PIIX4 specification update.  Applies to only older
79 		 * PIIX4 models.
80 		 */
81 		errata.piix4.throttle = 1;
82 		/* fall through*/
83 
84 	case 2:		/* PIIX4E */
85 	case 3:		/* PIIX4M */
86 		/*
87 		 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
88 		 * Livelock") from the January 2002 PIIX4 specification update.
89 		 * Applies to all PIIX4 models.
90 		 */
91 
92 		/*
93 		 * BM-IDE
94 		 * ------
95 		 * Find the PIIX4 IDE Controller and get the Bus Master IDE
96 		 * Status register address.  We'll use this later to read
97 		 * each IDE controller's DMA status to make sure we catch all
98 		 * DMA activity.
99 		 */
100 		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
101 				     PCI_DEVICE_ID_INTEL_82371AB,
102 				     PCI_ANY_ID, PCI_ANY_ID, NULL);
103 		if (dev) {
104 			errata.piix4.bmisx = pci_resource_start(dev, 4);
105 			pci_dev_put(dev);
106 		}
107 
108 		/*
109 		 * Type-F DMA
110 		 * ----------
111 		 * Find the PIIX4 ISA Controller and read the Motherboard
112 		 * DMA controller's status to see if Type-F (Fast) DMA mode
113 		 * is enabled (bit 7) on either channel.  Note that we'll
114 		 * disable C3 support if this is enabled, as some legacy
115 		 * devices won't operate well if fast DMA is disabled.
116 		 */
117 		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
118 				     PCI_DEVICE_ID_INTEL_82371AB_0,
119 				     PCI_ANY_ID, PCI_ANY_ID, NULL);
120 		if (dev) {
121 			pci_read_config_byte(dev, 0x76, &value1);
122 			pci_read_config_byte(dev, 0x77, &value2);
123 			if ((value1 & 0x80) || (value2 & 0x80))
124 				errata.piix4.fdma = 1;
125 			pci_dev_put(dev);
126 		}
127 
128 		break;
129 	}
130 
131 	if (errata.piix4.bmisx)
132 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
133 				  "Bus master activity detection (BM-IDE) erratum enabled\n"));
134 	if (errata.piix4.fdma)
135 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
136 				  "Type-F DMA livelock erratum (C3 disabled)\n"));
137 
138 	return 0;
139 }
140 
141 static int acpi_processor_errata(void)
142 {
143 	int result = 0;
144 	struct pci_dev *dev = NULL;
145 
146 	/*
147 	 * PIIX4
148 	 */
149 	dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
150 			     PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
151 			     PCI_ANY_ID, NULL);
152 	if (dev) {
153 		result = acpi_processor_errata_piix4(dev);
154 		pci_dev_put(dev);
155 	}
156 
157 	return result;
158 }
159 
160 /* --------------------------------------------------------------------------
161                                 Initialization
162    -------------------------------------------------------------------------- */
163 
164 #ifdef CONFIG_ACPI_HOTPLUG_CPU
165 int __weak acpi_map_cpu(acpi_handle handle,
166 		phys_cpuid_t physid, u32 acpi_id, int *pcpu)
167 {
168 	return -ENODEV;
169 }
170 
171 int __weak acpi_unmap_cpu(int cpu)
172 {
173 	return -ENODEV;
174 }
175 
176 int __weak arch_register_cpu(int cpu)
177 {
178 	return -ENODEV;
179 }
180 
181 void __weak arch_unregister_cpu(int cpu) {}
182 
183 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
184 {
185 	unsigned long long sta;
186 	acpi_status status;
187 	int ret;
188 
189 	if (invalid_phys_cpuid(pr->phys_id))
190 		return -ENODEV;
191 
192 	status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
193 	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
194 		return -ENODEV;
195 
196 	cpu_maps_update_begin();
197 	cpu_hotplug_begin();
198 
199 	ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
200 	if (ret)
201 		goto out;
202 
203 	ret = arch_register_cpu(pr->id);
204 	if (ret) {
205 		acpi_unmap_cpu(pr->id);
206 		goto out;
207 	}
208 
209 	/*
210 	 * CPU got hot-added, but cpu_data is not initialized yet.  Set a flag
211 	 * to delay cpu_idle/throttling initialization and do it when the CPU
212 	 * gets online for the first time.
213 	 */
214 	pr_info("CPU%d has been hot-added\n", pr->id);
215 	pr->flags.need_hotplug_init = 1;
216 
217 out:
218 	cpu_hotplug_done();
219 	cpu_maps_update_done();
220 	return ret;
221 }
222 #else
223 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
224 {
225 	return -ENODEV;
226 }
227 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
228 
229 static int acpi_processor_get_info(struct acpi_device *device)
230 {
231 	union acpi_object object = { 0 };
232 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
233 	struct acpi_processor *pr = acpi_driver_data(device);
234 	int device_declaration = 0;
235 	acpi_status status = AE_OK;
236 	static int cpu0_initialized;
237 	unsigned long long value;
238 
239 	acpi_processor_errata();
240 
241 	/*
242 	 * Check to see if we have bus mastering arbitration control.  This
243 	 * is required for proper C3 usage (to maintain cache coherency).
244 	 */
245 	if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
246 		pr->flags.bm_control = 1;
247 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
248 				  "Bus mastering arbitration control present\n"));
249 	} else
250 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
251 				  "No bus mastering arbitration control\n"));
252 
253 	if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
254 		/* Declared with "Processor" statement; match ProcessorID */
255 		status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
256 		if (ACPI_FAILURE(status)) {
257 			dev_err(&device->dev,
258 				"Failed to evaluate processor object (0x%x)\n",
259 				status);
260 			return -ENODEV;
261 		}
262 
263 		pr->acpi_id = object.processor.proc_id;
264 	} else {
265 		/*
266 		 * Declared with "Device" statement; match _UID.
267 		 * Note that we don't handle string _UIDs yet.
268 		 */
269 		status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
270 						NULL, &value);
271 		if (ACPI_FAILURE(status)) {
272 			dev_err(&device->dev,
273 				"Failed to evaluate processor _UID (0x%x)\n",
274 				status);
275 			return -ENODEV;
276 		}
277 		device_declaration = 1;
278 		pr->acpi_id = value;
279 	}
280 
281 	if (acpi_duplicate_processor_id(pr->acpi_id)) {
282 		if (pr->acpi_id == 0xff)
283 			dev_info_once(&device->dev,
284 				"Entry not well-defined, consider updating BIOS\n");
285 		else
286 			dev_err(&device->dev,
287 				"Failed to get unique processor _UID (0x%x)\n",
288 				pr->acpi_id);
289 		return -ENODEV;
290 	}
291 
292 	pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
293 					pr->acpi_id);
294 	if (invalid_phys_cpuid(pr->phys_id))
295 		acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
296 
297 	pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
298 	if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
299 		cpu0_initialized = 1;
300 		/*
301 		 * Handle UP system running SMP kernel, with no CPU
302 		 * entry in MADT
303 		 */
304 		if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
305 			pr->id = 0;
306 	}
307 
308 	/*
309 	 *  Extra Processor objects may be enumerated on MP systems with
310 	 *  less than the max # of CPUs. They should be ignored _iff
311 	 *  they are physically not present.
312 	 *
313 	 *  NOTE: Even if the processor has a cpuid, it may not be present
314 	 *  because cpuid <-> apicid mapping is persistent now.
315 	 */
316 	if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
317 		int ret = acpi_processor_hotadd_init(pr);
318 		if (ret)
319 			return ret;
320 	}
321 
322 	/*
323 	 * On some boxes several processors use the same processor bus id.
324 	 * But they are located in different scope. For example:
325 	 * \_SB.SCK0.CPU0
326 	 * \_SB.SCK1.CPU0
327 	 * Rename the processor device bus id. And the new bus id will be
328 	 * generated as the following format:
329 	 * CPU+CPU ID.
330 	 */
331 	sprintf(acpi_device_bid(device), "CPU%X", pr->id);
332 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
333 			  pr->acpi_id));
334 
335 	if (!object.processor.pblk_address)
336 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
337 	else if (object.processor.pblk_length != 6)
338 		dev_err(&device->dev, "Invalid PBLK length [%d]\n",
339 			    object.processor.pblk_length);
340 	else {
341 		pr->throttling.address = object.processor.pblk_address;
342 		pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
343 		pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
344 
345 		pr->pblk = object.processor.pblk_address;
346 	}
347 
348 	/*
349 	 * If ACPI describes a slot number for this CPU, we can use it to
350 	 * ensure we get the right value in the "physical id" field
351 	 * of /proc/cpuinfo
352 	 */
353 	status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
354 	if (ACPI_SUCCESS(status))
355 		arch_fix_phys_package_id(pr->id, value);
356 
357 	return 0;
358 }
359 
360 /*
361  * Do not put anything in here which needs the core to be online.
362  * For example MSR access or setting up things which check for cpuinfo_x86
363  * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
364  * Such things have to be put in and set up by the processor driver's .probe().
365  */
366 static DEFINE_PER_CPU(void *, processor_device_array);
367 
368 static int acpi_processor_add(struct acpi_device *device,
369 					const struct acpi_device_id *id)
370 {
371 	struct acpi_processor *pr;
372 	struct device *dev;
373 	int result = 0;
374 
375 	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
376 	if (!pr)
377 		return -ENOMEM;
378 
379 	if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
380 		result = -ENOMEM;
381 		goto err_free_pr;
382 	}
383 
384 	pr->handle = device->handle;
385 	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
386 	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
387 	device->driver_data = pr;
388 
389 	result = acpi_processor_get_info(device);
390 	if (result) /* Processor is not physically present or unavailable */
391 		return 0;
392 
393 	BUG_ON(pr->id >= nr_cpu_ids);
394 
395 	/*
396 	 * Buggy BIOS check.
397 	 * ACPI id of processors can be reported wrongly by the BIOS.
398 	 * Don't trust it blindly
399 	 */
400 	if (per_cpu(processor_device_array, pr->id) != NULL &&
401 	    per_cpu(processor_device_array, pr->id) != device) {
402 		dev_warn(&device->dev,
403 			"BIOS reported wrong ACPI id %d for the processor\n",
404 			pr->id);
405 		/* Give up, but do not abort the namespace scan. */
406 		goto err;
407 	}
408 	/*
409 	 * processor_device_array is not cleared on errors to allow buggy BIOS
410 	 * checks.
411 	 */
412 	per_cpu(processor_device_array, pr->id) = device;
413 	per_cpu(processors, pr->id) = pr;
414 
415 	dev = get_cpu_device(pr->id);
416 	if (!dev) {
417 		result = -ENODEV;
418 		goto err;
419 	}
420 
421 	result = acpi_bind_one(dev, device);
422 	if (result)
423 		goto err;
424 
425 	pr->dev = dev;
426 
427 	/* Trigger the processor driver's .probe() if present. */
428 	if (device_attach(dev) >= 0)
429 		return 1;
430 
431 	dev_err(dev, "Processor driver could not be attached\n");
432 	acpi_unbind_one(dev);
433 
434  err:
435 	free_cpumask_var(pr->throttling.shared_cpu_map);
436 	device->driver_data = NULL;
437 	per_cpu(processors, pr->id) = NULL;
438  err_free_pr:
439 	kfree(pr);
440 	return result;
441 }
442 
443 #ifdef CONFIG_ACPI_HOTPLUG_CPU
444 /* --------------------------------------------------------------------------
445                                     Removal
446    -------------------------------------------------------------------------- */
447 
448 static void acpi_processor_remove(struct acpi_device *device)
449 {
450 	struct acpi_processor *pr;
451 
452 	if (!device || !acpi_driver_data(device))
453 		return;
454 
455 	pr = acpi_driver_data(device);
456 	if (pr->id >= nr_cpu_ids)
457 		goto out;
458 
459 	/*
460 	 * The only reason why we ever get here is CPU hot-removal.  The CPU is
461 	 * already offline and the ACPI device removal locking prevents it from
462 	 * being put back online at this point.
463 	 *
464 	 * Unbind the driver from the processor device and detach it from the
465 	 * ACPI companion object.
466 	 */
467 	device_release_driver(pr->dev);
468 	acpi_unbind_one(pr->dev);
469 
470 	/* Clean up. */
471 	per_cpu(processor_device_array, pr->id) = NULL;
472 	per_cpu(processors, pr->id) = NULL;
473 
474 	cpu_maps_update_begin();
475 	cpu_hotplug_begin();
476 
477 	/* Remove the CPU. */
478 	arch_unregister_cpu(pr->id);
479 	acpi_unmap_cpu(pr->id);
480 
481 	cpu_hotplug_done();
482 	cpu_maps_update_done();
483 
484 	try_offline_node(cpu_to_node(pr->id));
485 
486  out:
487 	free_cpumask_var(pr->throttling.shared_cpu_map);
488 	kfree(pr);
489 }
490 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
491 
492 #ifdef CONFIG_X86
493 static bool acpi_hwp_native_thermal_lvt_set;
494 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
495 							  u32 lvl,
496 							  void *context,
497 							  void **rv)
498 {
499 	u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
500 	u32 capbuf[2];
501 	struct acpi_osc_context osc_context = {
502 		.uuid_str = sb_uuid_str,
503 		.rev = 1,
504 		.cap.length = 8,
505 		.cap.pointer = capbuf,
506 	};
507 
508 	if (acpi_hwp_native_thermal_lvt_set)
509 		return AE_CTRL_TERMINATE;
510 
511 	capbuf[0] = 0x0000;
512 	capbuf[1] = 0x1000; /* set bit 12 */
513 
514 	if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
515 		if (osc_context.ret.pointer && osc_context.ret.length > 1) {
516 			u32 *capbuf_ret = osc_context.ret.pointer;
517 
518 			if (capbuf_ret[1] & 0x1000) {
519 				acpi_handle_info(handle,
520 					"_OSC native thermal LVT Acked\n");
521 				acpi_hwp_native_thermal_lvt_set = true;
522 			}
523 		}
524 		kfree(osc_context.ret.pointer);
525 	}
526 
527 	return AE_OK;
528 }
529 
530 void __init acpi_early_processor_osc(void)
531 {
532 	if (boot_cpu_has(X86_FEATURE_HWP)) {
533 		acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
534 				    ACPI_UINT32_MAX,
535 				    acpi_hwp_native_thermal_lvt_osc,
536 				    NULL, NULL, NULL);
537 		acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
538 				 acpi_hwp_native_thermal_lvt_osc,
539 				 NULL, NULL);
540 	}
541 }
542 #endif
543 
544 /*
545  * The following ACPI IDs are known to be suitable for representing as
546  * processor devices.
547  */
548 static const struct acpi_device_id processor_device_ids[] = {
549 
550 	{ ACPI_PROCESSOR_OBJECT_HID, },
551 	{ ACPI_PROCESSOR_DEVICE_HID, },
552 
553 	{ }
554 };
555 
556 static struct acpi_scan_handler processor_handler = {
557 	.ids = processor_device_ids,
558 	.attach = acpi_processor_add,
559 #ifdef CONFIG_ACPI_HOTPLUG_CPU
560 	.detach = acpi_processor_remove,
561 #endif
562 	.hotplug = {
563 		.enabled = true,
564 	},
565 };
566 
567 static int acpi_processor_container_attach(struct acpi_device *dev,
568 					   const struct acpi_device_id *id)
569 {
570 	return 1;
571 }
572 
573 static const struct acpi_device_id processor_container_ids[] = {
574 	{ ACPI_PROCESSOR_CONTAINER_HID, },
575 	{ }
576 };
577 
578 static struct acpi_scan_handler processor_container_handler = {
579 	.ids = processor_container_ids,
580 	.attach = acpi_processor_container_attach,
581 };
582 
583 /* The number of the unique processor IDs */
584 static int nr_unique_ids __initdata;
585 
586 /* The number of the duplicate processor IDs */
587 static int nr_duplicate_ids;
588 
589 /* Used to store the unique processor IDs */
590 static int unique_processor_ids[] __initdata = {
591 	[0 ... NR_CPUS - 1] = -1,
592 };
593 
594 /* Used to store the duplicate processor IDs */
595 static int duplicate_processor_ids[] = {
596 	[0 ... NR_CPUS - 1] = -1,
597 };
598 
599 static void __init processor_validated_ids_update(int proc_id)
600 {
601 	int i;
602 
603 	if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
604 		return;
605 
606 	/*
607 	 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
608 	 * already in the IDs, do nothing.
609 	 */
610 	for (i = 0; i < nr_duplicate_ids; i++) {
611 		if (duplicate_processor_ids[i] == proc_id)
612 			return;
613 	}
614 
615 	/*
616 	 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
617 	 * the IDs, put it in the duplicate IDs.
618 	 */
619 	for (i = 0; i < nr_unique_ids; i++) {
620 		if (unique_processor_ids[i] == proc_id) {
621 			duplicate_processor_ids[nr_duplicate_ids] = proc_id;
622 			nr_duplicate_ids++;
623 			return;
624 		}
625 	}
626 
627 	/*
628 	 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
629 	 */
630 	unique_processor_ids[nr_unique_ids] = proc_id;
631 	nr_unique_ids++;
632 }
633 
634 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
635 						  u32 lvl,
636 						  void *context,
637 						  void **rv)
638 {
639 	acpi_status status;
640 	acpi_object_type acpi_type;
641 	unsigned long long uid;
642 	union acpi_object object = { 0 };
643 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
644 
645 	status = acpi_get_type(handle, &acpi_type);
646 	if (ACPI_FAILURE(status))
647 		return status;
648 
649 	switch (acpi_type) {
650 	case ACPI_TYPE_PROCESSOR:
651 		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
652 		if (ACPI_FAILURE(status))
653 			goto err;
654 		uid = object.processor.proc_id;
655 		break;
656 
657 	case ACPI_TYPE_DEVICE:
658 		status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
659 		if (ACPI_FAILURE(status))
660 			goto err;
661 		break;
662 	default:
663 		goto err;
664 	}
665 
666 	processor_validated_ids_update(uid);
667 	return AE_OK;
668 
669 err:
670 	/* Exit on error, but don't abort the namespace walk */
671 	acpi_handle_info(handle, "Invalid processor object\n");
672 	return AE_OK;
673 
674 }
675 
676 static void __init acpi_processor_check_duplicates(void)
677 {
678 	/* check the correctness for all processors in ACPI namespace */
679 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
680 						ACPI_UINT32_MAX,
681 						acpi_processor_ids_walk,
682 						NULL, NULL, NULL);
683 	acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
684 						NULL, NULL);
685 }
686 
687 bool acpi_duplicate_processor_id(int proc_id)
688 {
689 	int i;
690 
691 	/*
692 	 * compare the proc_id with duplicate IDs, if the proc_id is already
693 	 * in the duplicate IDs, return true, otherwise, return false.
694 	 */
695 	for (i = 0; i < nr_duplicate_ids; i++) {
696 		if (duplicate_processor_ids[i] == proc_id)
697 			return true;
698 	}
699 	return false;
700 }
701 
702 void __init acpi_processor_init(void)
703 {
704 	acpi_processor_check_duplicates();
705 	acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
706 	acpi_scan_add_handler(&processor_container_handler);
707 }
708