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v6.13.7
  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#define pr_fmt(fmt) "ACPI: " fmt
 13
 14#include <linux/acpi.h>
 15#include <linux/cpu.h>
 16#include <linux/device.h>
 17#include <linux/dmi.h>
 18#include <linux/kernel.h>
 19#include <linux/module.h>
 20#include <linux/pci.h>
 21#include <linux/platform_device.h>
 22
 23#include <acpi/processor.h>
 24
 25#include <asm/cpu.h>
 26
 27#include <xen/xen.h>
 28
 29#include "internal.h"
 30
 31DEFINE_PER_CPU(struct acpi_processor *, processors);
 32EXPORT_PER_CPU_SYMBOL(processors);
 33
 34/* Errata Handling */
 35struct acpi_processor_errata errata __read_mostly;
 36EXPORT_SYMBOL_GPL(errata);
 37
 38acpi_handle acpi_get_processor_handle(int cpu)
 39{
 40	struct acpi_processor *pr;
 41
 42	pr = per_cpu(processors, cpu);
 43	if (pr)
 44		return pr->handle;
 45
 46	return NULL;
 47}
 48
 49static int acpi_processor_errata_piix4(struct pci_dev *dev)
 50{
 51	u8 value1 = 0;
 52	u8 value2 = 0;
 53
 54
 55	if (!dev)
 56		return -EINVAL;
 57
 58	/*
 59	 * Note that 'dev' references the PIIX4 ACPI Controller.
 60	 */
 61
 62	switch (dev->revision) {
 63	case 0:
 64		dev_dbg(&dev->dev, "Found PIIX4 A-step\n");
 65		break;
 66	case 1:
 67		dev_dbg(&dev->dev, "Found PIIX4 B-step\n");
 68		break;
 69	case 2:
 70		dev_dbg(&dev->dev, "Found PIIX4E\n");
 71		break;
 72	case 3:
 73		dev_dbg(&dev->dev, "Found PIIX4M\n");
 74		break;
 75	default:
 76		dev_dbg(&dev->dev, "Found unknown PIIX4\n");
 77		break;
 78	}
 79
 80	switch (dev->revision) {
 81
 82	case 0:		/* PIIX4 A-step */
 83	case 1:		/* PIIX4 B-step */
 84		/*
 85		 * See specification changes #13 ("Manual Throttle Duty Cycle")
 86		 * and #14 ("Enabling and Disabling Manual Throttle"), plus
 87		 * erratum #5 ("STPCLK# Deassertion Time") from the January
 88		 * 2002 PIIX4 specification update.  Applies to only older
 89		 * PIIX4 models.
 90		 */
 91		errata.piix4.throttle = 1;
 92		fallthrough;
 93
 94	case 2:		/* PIIX4E */
 95	case 3:		/* PIIX4M */
 96		/*
 97		 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
 98		 * Livelock") from the January 2002 PIIX4 specification update.
 99		 * Applies to all PIIX4 models.
100		 */
101
102		/*
103		 * BM-IDE
104		 * ------
105		 * Find the PIIX4 IDE Controller and get the Bus Master IDE
106		 * Status register address.  We'll use this later to read
107		 * each IDE controller's DMA status to make sure we catch all
108		 * DMA activity.
109		 */
110		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
111				     PCI_DEVICE_ID_INTEL_82371AB,
112				     PCI_ANY_ID, PCI_ANY_ID, NULL);
113		if (dev) {
114			errata.piix4.bmisx = pci_resource_start(dev, 4);
115			pci_dev_put(dev);
116		}
117
118		/*
119		 * Type-F DMA
120		 * ----------
121		 * Find the PIIX4 ISA Controller and read the Motherboard
122		 * DMA controller's status to see if Type-F (Fast) DMA mode
123		 * is enabled (bit 7) on either channel.  Note that we'll
124		 * disable C3 support if this is enabled, as some legacy
125		 * devices won't operate well if fast DMA is disabled.
126		 */
127		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
128				     PCI_DEVICE_ID_INTEL_82371AB_0,
129				     PCI_ANY_ID, PCI_ANY_ID, NULL);
130		if (dev) {
131			pci_read_config_byte(dev, 0x76, &value1);
132			pci_read_config_byte(dev, 0x77, &value2);
133			if ((value1 & 0x80) || (value2 & 0x80))
134				errata.piix4.fdma = 1;
135			pci_dev_put(dev);
136		}
137
138		break;
139	}
140
141	if (errata.piix4.bmisx)
142		dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");
143	if (errata.piix4.fdma)
144		dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");
145
146	return 0;
147}
148
149static int acpi_processor_errata(void)
150{
151	int result = 0;
152	struct pci_dev *dev = NULL;
153
154	/*
155	 * PIIX4
156	 */
157	dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
158			     PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
159			     PCI_ANY_ID, NULL);
160	if (dev) {
161		result = acpi_processor_errata_piix4(dev);
162		pci_dev_put(dev);
163	}
164
165	return result;
166}
167
168/* Create a platform device to represent a CPU frequency control mechanism. */
169static void cpufreq_add_device(const char *name)
170{
171	struct platform_device *pdev;
172
173	pdev = platform_device_register_simple(name, PLATFORM_DEVID_NONE, NULL, 0);
174	if (IS_ERR(pdev))
175		pr_info("%s device creation failed: %pe\n", name, pdev);
176}
177
178#ifdef CONFIG_X86
179/* Check presence of Processor Clocking Control by searching for \_SB.PCCH. */
180static void __init acpi_pcc_cpufreq_init(void)
181{
182	acpi_status status;
183	acpi_handle handle;
184
185	status = acpi_get_handle(NULL, "\\_SB", &handle);
186	if (ACPI_FAILURE(status))
187		return;
188
189	if (acpi_has_method(handle, "PCCH"))
190		cpufreq_add_device("pcc-cpufreq");
191}
192#else
193static void __init acpi_pcc_cpufreq_init(void) {}
194#endif /* CONFIG_X86 */
195
196/* Initialization */
197static DEFINE_PER_CPU(void *, processor_device_array);
198
199static int acpi_processor_set_per_cpu(struct acpi_processor *pr,
200				      struct acpi_device *device)
201{
202	BUG_ON(pr->id >= nr_cpu_ids);
203
204	/*
205	 * Buggy BIOS check.
206	 * ACPI id of processors can be reported wrongly by the BIOS.
207	 * Don't trust it blindly
208	 */
209	if (per_cpu(processor_device_array, pr->id) != NULL &&
210	    per_cpu(processor_device_array, pr->id) != device) {
211		dev_warn(&device->dev,
212			 "BIOS reported wrong ACPI id %d for the processor\n",
213			 pr->id);
214		return -EINVAL;
215	}
216	/*
217	 * processor_device_array is not cleared on errors to allow buggy BIOS
218	 * checks.
219	 */
220	per_cpu(processor_device_array, pr->id) = device;
221	per_cpu(processors, pr->id) = pr;
222
223	return 0;
224}
225
226#ifdef CONFIG_ACPI_HOTPLUG_CPU
227static int acpi_processor_hotadd_init(struct acpi_processor *pr,
228				      struct acpi_device *device)
229{
 
 
230	int ret;
231
232	if (invalid_phys_cpuid(pr->phys_id))
233		return -ENODEV;
234
 
 
 
 
235	cpu_maps_update_begin();
236	cpus_write_lock();
237
238	ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
239	if (ret)
240		goto out;
241
242	ret = acpi_processor_set_per_cpu(pr, device);
243	if (ret) {
244		acpi_unmap_cpu(pr->id);
245		goto out;
246	}
247
248	ret = arch_register_cpu(pr->id);
249	if (ret) {
250		/* Leave the processor device array in place to detect buggy bios */
251		per_cpu(processors, pr->id) = NULL;
252		acpi_unmap_cpu(pr->id);
253		goto out;
254	}
255
256	/*
257	 * CPU got hot-added, but cpu_data is not initialized yet. Do
258	 * cpu_idle/throttling initialization when the CPU gets online for
259	 * the first time.
260	 */
261	pr_info("CPU%d has been hot-added\n", pr->id);
 
262
263out:
264	cpus_write_unlock();
265	cpu_maps_update_done();
266	return ret;
267}
268#else
269static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,
270					     struct acpi_device *device)
271{
272	return -ENODEV;
273}
274#endif /* CONFIG_ACPI_HOTPLUG_CPU */
275
276static int acpi_processor_get_info(struct acpi_device *device)
277{
278	union acpi_object object = { 0 };
279	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
280	struct acpi_processor *pr = acpi_driver_data(device);
281	int device_declaration = 0;
282	acpi_status status = AE_OK;
283	static int cpu0_initialized;
284	unsigned long long value;
285	int ret;
286
287	acpi_processor_errata();
288
289	/*
290	 * Check to see if we have bus mastering arbitration control.  This
291	 * is required for proper C3 usage (to maintain cache coherency).
292	 */
293	if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
294		pr->flags.bm_control = 1;
295		dev_dbg(&device->dev, "Bus mastering arbitration control present\n");
296	} else
297		dev_dbg(&device->dev, "No bus mastering arbitration control\n");
298
299	if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
300		/* Declared with "Processor" statement; match ProcessorID */
301		status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
302		if (ACPI_FAILURE(status)) {
303			dev_err(&device->dev,
304				"Failed to evaluate processor object (0x%x)\n",
305				status);
306			return -ENODEV;
307		}
308
309		pr->acpi_id = object.processor.proc_id;
310	} else {
311		/*
312		 * Declared with "Device" statement; match _UID.
313		 */
314		status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
315						NULL, &value);
316		if (ACPI_FAILURE(status)) {
317			dev_err(&device->dev,
318				"Failed to evaluate processor _UID (0x%x)\n",
319				status);
320			return -ENODEV;
321		}
322		device_declaration = 1;
323		pr->acpi_id = value;
324	}
325
326	if (acpi_duplicate_processor_id(pr->acpi_id)) {
327		if (pr->acpi_id == 0xff)
328			dev_info_once(&device->dev,
329				"Entry not well-defined, consider updating BIOS\n");
330		else
331			dev_err(&device->dev,
332				"Failed to get unique processor _UID (0x%x)\n",
333				pr->acpi_id);
334		return -ENODEV;
335	}
336
337	pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
338					pr->acpi_id);
339	if (invalid_phys_cpuid(pr->phys_id))
340		dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");
341
342	pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
343	if (!cpu0_initialized) {
344		cpu0_initialized = 1;
345		/*
346		 * Handle UP system running SMP kernel, with no CPU
347		 * entry in MADT
348		 */
349		if (!acpi_has_cpu_in_madt() && invalid_logical_cpuid(pr->id) &&
350		    (num_online_cpus() == 1))
351			pr->id = 0;
352		/*
353		 * Check availability of Processor Performance Control by
354		 * looking at the presence of the _PCT object under the first
355		 * processor definition.
356		 */
357		if (acpi_has_method(pr->handle, "_PCT"))
358			cpufreq_add_device("acpi-cpufreq");
359	}
360
361	/*
362	 *  This code is not called unless we know the CPU is present and
363	 *  enabled. The two paths are:
364	 *  a) Initially present CPUs on architectures that do not defer
365	 *     their arch_register_cpu() calls until this point.
366	 *  b) Hotplugged CPUs (enabled bit in _STA has transitioned from not
367	 *     enabled to enabled)
368	 */
369	if (!get_cpu_device(pr->id))
370		ret = acpi_processor_hotadd_init(pr, device);
371	else
372		ret = acpi_processor_set_per_cpu(pr, device);
373	if (ret)
374		return ret;
375
376	/*
377	 * On some boxes several processors use the same processor bus id.
378	 * But they are located in different scope. For example:
379	 * \_SB.SCK0.CPU0
380	 * \_SB.SCK1.CPU0
381	 * Rename the processor device bus id. And the new bus id will be
382	 * generated as the following format:
383	 * CPU+CPU ID.
384	 */
385	sprintf(acpi_device_bid(device), "CPU%X", pr->id);
386	dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);
387
388	if (!object.processor.pblk_address)
389		dev_dbg(&device->dev, "No PBLK (NULL address)\n");
390	else if (object.processor.pblk_length != 6)
391		dev_err(&device->dev, "Invalid PBLK length [%d]\n",
392			    object.processor.pblk_length);
393	else {
394		pr->throttling.address = object.processor.pblk_address;
395		pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
396		pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
397
398		pr->pblk = object.processor.pblk_address;
399	}
400
401	/*
402	 * If ACPI describes a slot number for this CPU, we can use it to
403	 * ensure we get the right value in the "physical id" field
404	 * of /proc/cpuinfo
405	 */
406	status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
407	if (ACPI_SUCCESS(status))
408		arch_fix_phys_package_id(pr->id, value);
409
410	return 0;
411}
412
413/*
414 * Do not put anything in here which needs the core to be online.
415 * For example MSR access or setting up things which check for cpuinfo_x86
416 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
417 * Such things have to be put in and set up by the processor driver's .probe().
418 */
 
 
419static int acpi_processor_add(struct acpi_device *device,
420					const struct acpi_device_id *id)
421{
422	struct acpi_processor *pr;
423	struct device *dev;
424	int result = 0;
425
426	if (!acpi_device_is_enabled(device))
427		return -ENODEV;
428
429	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
430	if (!pr)
431		return -ENOMEM;
432
433	if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
434		result = -ENOMEM;
435		goto err_free_pr;
436	}
437
438	pr->handle = device->handle;
439	strscpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
440	strscpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
441	device->driver_data = pr;
442
443	result = acpi_processor_get_info(device);
444	if (result) /* Processor is not physically present or unavailable */
445		goto err_clear_driver_data;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
446
447	dev = get_cpu_device(pr->id);
448	if (!dev) {
449		result = -ENODEV;
450		goto err_clear_per_cpu;
451	}
452
453	result = acpi_bind_one(dev, device);
454	if (result)
455		goto err_clear_per_cpu;
456
457	pr->dev = dev;
458
459	/* Trigger the processor driver's .probe() if present. */
460	if (device_attach(dev) >= 0)
461		return 1;
462
463	dev_err(dev, "Processor driver could not be attached\n");
464	acpi_unbind_one(dev);
465
466 err_clear_per_cpu:
467	per_cpu(processors, pr->id) = NULL;
468 err_clear_driver_data:
469	device->driver_data = NULL;
470	free_cpumask_var(pr->throttling.shared_cpu_map);
 
 
471 err_free_pr:
472	kfree(pr);
473	return result;
474}
475
476#ifdef CONFIG_ACPI_HOTPLUG_CPU
477/* Removal */
478static void acpi_processor_post_eject(struct acpi_device *device)
479{
480	struct acpi_processor *pr;
481
482	if (!device || !acpi_driver_data(device))
483		return;
484
485	pr = acpi_driver_data(device);
486	if (pr->id >= nr_cpu_ids)
487		goto out;
488
489	/*
490	 * The only reason why we ever get here is CPU hot-removal.  The CPU is
491	 * already offline and the ACPI device removal locking prevents it from
492	 * being put back online at this point.
493	 *
494	 * Unbind the driver from the processor device and detach it from the
495	 * ACPI companion object.
496	 */
497	device_release_driver(pr->dev);
498	acpi_unbind_one(pr->dev);
499
 
 
 
 
500	cpu_maps_update_begin();
501	cpus_write_lock();
502
503	/* Remove the CPU. */
504	arch_unregister_cpu(pr->id);
505	acpi_unmap_cpu(pr->id);
506
507	/* Clean up. */
508	per_cpu(processor_device_array, pr->id) = NULL;
509	per_cpu(processors, pr->id) = NULL;
510
511	cpus_write_unlock();
512	cpu_maps_update_done();
513
514	try_offline_node(cpu_to_node(pr->id));
515
516 out:
517	free_cpumask_var(pr->throttling.shared_cpu_map);
518	kfree(pr);
519}
520#endif /* CONFIG_ACPI_HOTPLUG_CPU */
521
522#ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
523bool __init processor_physically_present(acpi_handle handle)
524{
525	int cpuid, type;
526	u32 acpi_id;
527	acpi_status status;
528	acpi_object_type acpi_type;
529	unsigned long long tmp;
530	union acpi_object object = {};
531	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
532
533	status = acpi_get_type(handle, &acpi_type);
534	if (ACPI_FAILURE(status))
535		return false;
536
537	switch (acpi_type) {
538	case ACPI_TYPE_PROCESSOR:
539		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
540		if (ACPI_FAILURE(status))
541			return false;
542		acpi_id = object.processor.proc_id;
543		break;
544	case ACPI_TYPE_DEVICE:
545		status = acpi_evaluate_integer(handle, METHOD_NAME__UID,
546					       NULL, &tmp);
547		if (ACPI_FAILURE(status))
548			return false;
549		acpi_id = tmp;
550		break;
551	default:
552		return false;
553	}
554
555	if (xen_initial_domain())
556		/*
557		 * When running as a Xen dom0 the number of processors Linux
558		 * sees can be different from the real number of processors on
559		 * the system, and we still need to execute _PDC or _OSC for
560		 * all of them.
561		 */
562		return xen_processor_present(acpi_id);
563
564	type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
565	cpuid = acpi_get_cpuid(handle, type, acpi_id);
566
567	return !invalid_logical_cpuid(cpuid);
568}
569
570/* vendor specific UUID indicating an Intel platform */
571static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
572
573static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl,
574					     void *context, void **rv)
575{
576	u32 capbuf[2] = {};
577	struct acpi_osc_context osc_context = {
578		.uuid_str = sb_uuid_str,
579		.rev = 1,
580		.cap.length = 8,
581		.cap.pointer = capbuf,
582	};
583	acpi_status status;
584
585	if (!processor_physically_present(handle))
586		return AE_OK;
587
588	arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]);
589
590	status = acpi_run_osc(handle, &osc_context);
591	if (ACPI_FAILURE(status))
592		return status;
593
594	kfree(osc_context.ret.pointer);
595
596	return AE_OK;
597}
598
599static bool __init acpi_early_processor_osc(void)
600{
601	acpi_status status;
602
603	acpi_proc_quirk_mwait_check();
604
605	status = acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
606				     ACPI_UINT32_MAX, acpi_processor_osc, NULL,
607				     NULL, NULL);
608	if (ACPI_FAILURE(status))
609		return false;
610
611	status = acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_osc,
612				  NULL, NULL);
613	if (ACPI_FAILURE(status))
614		return false;
615
616	return true;
617}
618
619void __init acpi_early_processor_control_setup(void)
620{
621	if (acpi_early_processor_osc()) {
622		pr_debug("_OSC evaluated successfully for all CPUs\n");
623	} else {
624		pr_debug("_OSC evaluation for CPUs failed, trying _PDC\n");
625		acpi_early_processor_set_pdc();
626	}
627}
628#endif
629
630/*
631 * The following ACPI IDs are known to be suitable for representing as
632 * processor devices.
633 */
634static const struct acpi_device_id processor_device_ids[] = {
635
636	{ ACPI_PROCESSOR_OBJECT_HID, },
637	{ ACPI_PROCESSOR_DEVICE_HID, },
638
639	{ }
640};
641
642static struct acpi_scan_handler processor_handler = {
643	.ids = processor_device_ids,
644	.attach = acpi_processor_add,
645#ifdef CONFIG_ACPI_HOTPLUG_CPU
646	.post_eject = acpi_processor_post_eject,
647#endif
648	.hotplug = {
649		.enabled = true,
650	},
651};
652
653static int acpi_processor_container_attach(struct acpi_device *dev,
654					   const struct acpi_device_id *id)
655{
656	return 1;
657}
658
659static const struct acpi_device_id processor_container_ids[] = {
660	{ ACPI_PROCESSOR_CONTAINER_HID, },
661	{ }
662};
663
664static struct acpi_scan_handler processor_container_handler = {
665	.ids = processor_container_ids,
666	.attach = acpi_processor_container_attach,
667};
668
669/* The number of the unique processor IDs */
670static int nr_unique_ids __initdata;
671
672/* The number of the duplicate processor IDs */
673static int nr_duplicate_ids;
674
675/* Used to store the unique processor IDs */
676static int unique_processor_ids[] __initdata = {
677	[0 ... NR_CPUS - 1] = -1,
678};
679
680/* Used to store the duplicate processor IDs */
681static int duplicate_processor_ids[] = {
682	[0 ... NR_CPUS - 1] = -1,
683};
684
685static void __init processor_validated_ids_update(int proc_id)
686{
687	int i;
688
689	if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
690		return;
691
692	/*
693	 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
694	 * already in the IDs, do nothing.
695	 */
696	for (i = 0; i < nr_duplicate_ids; i++) {
697		if (duplicate_processor_ids[i] == proc_id)
698			return;
699	}
700
701	/*
702	 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
703	 * the IDs, put it in the duplicate IDs.
704	 */
705	for (i = 0; i < nr_unique_ids; i++) {
706		if (unique_processor_ids[i] == proc_id) {
707			duplicate_processor_ids[nr_duplicate_ids] = proc_id;
708			nr_duplicate_ids++;
709			return;
710		}
711	}
712
713	/*
714	 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
715	 */
716	unique_processor_ids[nr_unique_ids] = proc_id;
717	nr_unique_ids++;
718}
719
720static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
721						  u32 lvl,
722						  void *context,
723						  void **rv)
724{
725	acpi_status status;
726	acpi_object_type acpi_type;
727	unsigned long long uid;
728	union acpi_object object = { 0 };
729	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
730
731	status = acpi_get_type(handle, &acpi_type);
732	if (ACPI_FAILURE(status))
733		return status;
734
735	switch (acpi_type) {
736	case ACPI_TYPE_PROCESSOR:
737		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
738		if (ACPI_FAILURE(status))
739			goto err;
740		uid = object.processor.proc_id;
741		break;
742
743	case ACPI_TYPE_DEVICE:
744		status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
745		if (ACPI_FAILURE(status))
746			goto err;
747		break;
748	default:
749		goto err;
750	}
751
752	processor_validated_ids_update(uid);
753	return AE_OK;
754
755err:
756	/* Exit on error, but don't abort the namespace walk */
757	acpi_handle_info(handle, "Invalid processor object\n");
758	return AE_OK;
759
760}
761
762static void __init acpi_processor_check_duplicates(void)
763{
764	/* check the correctness for all processors in ACPI namespace */
765	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
766						ACPI_UINT32_MAX,
767						acpi_processor_ids_walk,
768						NULL, NULL, NULL);
769	acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
770						NULL, NULL);
771}
772
773bool acpi_duplicate_processor_id(int proc_id)
774{
775	int i;
776
777	/*
778	 * compare the proc_id with duplicate IDs, if the proc_id is already
779	 * in the duplicate IDs, return true, otherwise, return false.
780	 */
781	for (i = 0; i < nr_duplicate_ids; i++) {
782		if (duplicate_processor_ids[i] == proc_id)
783			return true;
784	}
785	return false;
786}
787
788void __init acpi_processor_init(void)
789{
790	acpi_processor_check_duplicates();
791	acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
792	acpi_scan_add_handler(&processor_container_handler);
793	acpi_pcc_cpufreq_init();
794}
795
796#ifdef CONFIG_ACPI_PROCESSOR_CSTATE
797/**
798 * acpi_processor_claim_cst_control - Request _CST control from the platform.
799 */
800bool acpi_processor_claim_cst_control(void)
801{
802	static bool cst_control_claimed;
803	acpi_status status;
804
805	if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
806		return true;
807
808	status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
809				    acpi_gbl_FADT.cst_control, 8);
810	if (ACPI_FAILURE(status)) {
811		pr_warn("ACPI: Failed to claim processor _CST control\n");
812		return false;
813	}
814
815	cst_control_claimed = true;
816	return true;
817}
818EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
819
820/**
821 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
822 * @handle: ACPI handle of the processor object containing the _CST.
823 * @cpu: The numeric ID of the target CPU.
824 * @info: Object write the C-states information into.
825 *
826 * Extract the C-state information for the given CPU from the output of the _CST
827 * control method under the corresponding ACPI processor object (or processor
828 * device object) and populate @info with it.
829 *
830 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
831 * acpi_processor_ffh_cstate_probe() to verify them and update the
832 * cpu_cstate_entry data for @cpu.
833 */
834int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
835				struct acpi_processor_power *info)
836{
837	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
838	union acpi_object *cst;
839	acpi_status status;
840	u64 count;
841	int last_index = 0;
842	int i, ret = 0;
843
844	status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
845	if (ACPI_FAILURE(status)) {
846		acpi_handle_debug(handle, "No _CST\n");
847		return -ENODEV;
848	}
849
850	cst = buffer.pointer;
851
852	/* There must be at least 2 elements. */
853	if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
854		acpi_handle_warn(handle, "Invalid _CST output\n");
855		ret = -EFAULT;
856		goto end;
857	}
858
859	count = cst->package.elements[0].integer.value;
860
861	/* Validate the number of C-states. */
862	if (count < 1 || count != cst->package.count - 1) {
863		acpi_handle_warn(handle, "Inconsistent _CST data\n");
864		ret = -EFAULT;
865		goto end;
866	}
867
868	for (i = 1; i <= count; i++) {
869		union acpi_object *element;
870		union acpi_object *obj;
871		struct acpi_power_register *reg;
872		struct acpi_processor_cx cx;
873
874		/*
875		 * If there is not enough space for all C-states, skip the
876		 * excess ones and log a warning.
877		 */
878		if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
879			acpi_handle_warn(handle,
880					 "No room for more idle states (limit: %d)\n",
881					 ACPI_PROCESSOR_MAX_POWER - 1);
882			break;
883		}
884
885		memset(&cx, 0, sizeof(cx));
886
887		element = &cst->package.elements[i];
888		if (element->type != ACPI_TYPE_PACKAGE) {
889			acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
890					 i, element->type);
891			continue;
892		}
893
894		if (element->package.count != 4) {
895			acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
896					 i, element->package.count);
897			continue;
898		}
899
900		obj = &element->package.elements[0];
901
902		if (obj->type != ACPI_TYPE_BUFFER) {
903			acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
904					 i, obj->type);
905			continue;
906		}
907
908		reg = (struct acpi_power_register *)obj->buffer.pointer;
909
910		obj = &element->package.elements[1];
911		if (obj->type != ACPI_TYPE_INTEGER) {
912			acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
913					 i, obj->type);
914			continue;
915		}
916
917		cx.type = obj->integer.value;
918		/*
919		 * There are known cases in which the _CST output does not
920		 * contain C1, so if the type of the first state found is not
921		 * C1, leave an empty slot for C1 to be filled in later.
922		 */
923		if (i == 1 && cx.type != ACPI_STATE_C1)
924			last_index = 1;
925
926		cx.address = reg->address;
927		cx.index = last_index + 1;
928
929		if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
930			if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
931				/*
932				 * In the majority of cases _CST describes C1 as
933				 * a FIXED_HARDWARE C-state, but if the command
934				 * line forbids using MWAIT, use CSTATE_HALT for
935				 * C1 regardless.
936				 */
937				if (cx.type == ACPI_STATE_C1 &&
938				    boot_option_idle_override == IDLE_NOMWAIT) {
939					cx.entry_method = ACPI_CSTATE_HALT;
940					snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
941				} else {
942					cx.entry_method = ACPI_CSTATE_FFH;
943				}
944			} else if (cx.type == ACPI_STATE_C1) {
945				/*
946				 * In the special case of C1, FIXED_HARDWARE can
947				 * be handled by executing the HLT instruction.
948				 */
949				cx.entry_method = ACPI_CSTATE_HALT;
950				snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
951			} else {
952				acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
953						 i);
954				continue;
955			}
956		} else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
957			cx.entry_method = ACPI_CSTATE_SYSTEMIO;
958			snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
959				 cx.address);
960		} else {
961			acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
962					 i, reg->space_id);
963			continue;
964		}
965
966		if (cx.type == ACPI_STATE_C1)
967			cx.valid = 1;
968
969		obj = &element->package.elements[2];
970		if (obj->type != ACPI_TYPE_INTEGER) {
971			acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
972					 i, obj->type);
973			continue;
974		}
975
976		cx.latency = obj->integer.value;
977
978		obj = &element->package.elements[3];
979		if (obj->type != ACPI_TYPE_INTEGER) {
980			acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
981					 i, obj->type);
982			continue;
983		}
984
985		memcpy(&info->states[++last_index], &cx, sizeof(cx));
986	}
987
988	acpi_handle_debug(handle, "Found %d idle states\n", last_index);
989
990	info->count = last_index;
991
992end:
993	kfree(buffer.pointer);
994
995	return ret;
996}
997EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
998#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */
v6.8
  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#define pr_fmt(fmt) "ACPI: " fmt
 13
 14#include <linux/acpi.h>
 15#include <linux/cpu.h>
 16#include <linux/device.h>
 17#include <linux/dmi.h>
 18#include <linux/kernel.h>
 19#include <linux/module.h>
 20#include <linux/pci.h>
 21#include <linux/platform_device.h>
 22
 23#include <acpi/processor.h>
 24
 25#include <asm/cpu.h>
 26
 27#include <xen/xen.h>
 28
 29#include "internal.h"
 30
 31DEFINE_PER_CPU(struct acpi_processor *, processors);
 32EXPORT_PER_CPU_SYMBOL(processors);
 33
 34/* Errata Handling */
 35struct acpi_processor_errata errata __read_mostly;
 36EXPORT_SYMBOL_GPL(errata);
 37
 
 
 
 
 
 
 
 
 
 
 
 38static int acpi_processor_errata_piix4(struct pci_dev *dev)
 39{
 40	u8 value1 = 0;
 41	u8 value2 = 0;
 42
 43
 44	if (!dev)
 45		return -EINVAL;
 46
 47	/*
 48	 * Note that 'dev' references the PIIX4 ACPI Controller.
 49	 */
 50
 51	switch (dev->revision) {
 52	case 0:
 53		dev_dbg(&dev->dev, "Found PIIX4 A-step\n");
 54		break;
 55	case 1:
 56		dev_dbg(&dev->dev, "Found PIIX4 B-step\n");
 57		break;
 58	case 2:
 59		dev_dbg(&dev->dev, "Found PIIX4E\n");
 60		break;
 61	case 3:
 62		dev_dbg(&dev->dev, "Found PIIX4M\n");
 63		break;
 64	default:
 65		dev_dbg(&dev->dev, "Found unknown PIIX4\n");
 66		break;
 67	}
 68
 69	switch (dev->revision) {
 70
 71	case 0:		/* PIIX4 A-step */
 72	case 1:		/* PIIX4 B-step */
 73		/*
 74		 * See specification changes #13 ("Manual Throttle Duty Cycle")
 75		 * and #14 ("Enabling and Disabling Manual Throttle"), plus
 76		 * erratum #5 ("STPCLK# Deassertion Time") from the January
 77		 * 2002 PIIX4 specification update.  Applies to only older
 78		 * PIIX4 models.
 79		 */
 80		errata.piix4.throttle = 1;
 81		fallthrough;
 82
 83	case 2:		/* PIIX4E */
 84	case 3:		/* PIIX4M */
 85		/*
 86		 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
 87		 * Livelock") from the January 2002 PIIX4 specification update.
 88		 * Applies to all PIIX4 models.
 89		 */
 90
 91		/*
 92		 * BM-IDE
 93		 * ------
 94		 * Find the PIIX4 IDE Controller and get the Bus Master IDE
 95		 * Status register address.  We'll use this later to read
 96		 * each IDE controller's DMA status to make sure we catch all
 97		 * DMA activity.
 98		 */
 99		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
100				     PCI_DEVICE_ID_INTEL_82371AB,
101				     PCI_ANY_ID, PCI_ANY_ID, NULL);
102		if (dev) {
103			errata.piix4.bmisx = pci_resource_start(dev, 4);
104			pci_dev_put(dev);
105		}
106
107		/*
108		 * Type-F DMA
109		 * ----------
110		 * Find the PIIX4 ISA Controller and read the Motherboard
111		 * DMA controller's status to see if Type-F (Fast) DMA mode
112		 * is enabled (bit 7) on either channel.  Note that we'll
113		 * disable C3 support if this is enabled, as some legacy
114		 * devices won't operate well if fast DMA is disabled.
115		 */
116		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
117				     PCI_DEVICE_ID_INTEL_82371AB_0,
118				     PCI_ANY_ID, PCI_ANY_ID, NULL);
119		if (dev) {
120			pci_read_config_byte(dev, 0x76, &value1);
121			pci_read_config_byte(dev, 0x77, &value2);
122			if ((value1 & 0x80) || (value2 & 0x80))
123				errata.piix4.fdma = 1;
124			pci_dev_put(dev);
125		}
126
127		break;
128	}
129
130	if (errata.piix4.bmisx)
131		dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");
132	if (errata.piix4.fdma)
133		dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");
134
135	return 0;
136}
137
138static int acpi_processor_errata(void)
139{
140	int result = 0;
141	struct pci_dev *dev = NULL;
142
143	/*
144	 * PIIX4
145	 */
146	dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
147			     PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
148			     PCI_ANY_ID, NULL);
149	if (dev) {
150		result = acpi_processor_errata_piix4(dev);
151		pci_dev_put(dev);
152	}
153
154	return result;
155}
156
157/* Create a platform device to represent a CPU frequency control mechanism. */
158static void cpufreq_add_device(const char *name)
159{
160	struct platform_device *pdev;
161
162	pdev = platform_device_register_simple(name, PLATFORM_DEVID_NONE, NULL, 0);
163	if (IS_ERR(pdev))
164		pr_info("%s device creation failed: %ld\n", name, PTR_ERR(pdev));
165}
166
167#ifdef CONFIG_X86
168/* Check presence of Processor Clocking Control by searching for \_SB.PCCH. */
169static void __init acpi_pcc_cpufreq_init(void)
170{
171	acpi_status status;
172	acpi_handle handle;
173
174	status = acpi_get_handle(NULL, "\\_SB", &handle);
175	if (ACPI_FAILURE(status))
176		return;
177
178	if (acpi_has_method(handle, "PCCH"))
179		cpufreq_add_device("pcc-cpufreq");
180}
181#else
182static void __init acpi_pcc_cpufreq_init(void) {}
183#endif /* CONFIG_X86 */
184
185/* Initialization */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
186#ifdef CONFIG_ACPI_HOTPLUG_CPU
187static int acpi_processor_hotadd_init(struct acpi_processor *pr)
 
188{
189	unsigned long long sta;
190	acpi_status status;
191	int ret;
192
193	if (invalid_phys_cpuid(pr->phys_id))
194		return -ENODEV;
195
196	status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
197	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
198		return -ENODEV;
199
200	cpu_maps_update_begin();
201	cpus_write_lock();
202
203	ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
204	if (ret)
205		goto out;
206
 
 
 
 
 
 
207	ret = arch_register_cpu(pr->id);
208	if (ret) {
 
 
209		acpi_unmap_cpu(pr->id);
210		goto out;
211	}
212
213	/*
214	 * CPU got hot-added, but cpu_data is not initialized yet.  Set a flag
215	 * to delay cpu_idle/throttling initialization and do it when the CPU
216	 * gets online for the first time.
217	 */
218	pr_info("CPU%d has been hot-added\n", pr->id);
219	pr->flags.need_hotplug_init = 1;
220
221out:
222	cpus_write_unlock();
223	cpu_maps_update_done();
224	return ret;
225}
226#else
227static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
 
228{
229	return -ENODEV;
230}
231#endif /* CONFIG_ACPI_HOTPLUG_CPU */
232
233static int acpi_processor_get_info(struct acpi_device *device)
234{
235	union acpi_object object = { 0 };
236	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
237	struct acpi_processor *pr = acpi_driver_data(device);
238	int device_declaration = 0;
239	acpi_status status = AE_OK;
240	static int cpu0_initialized;
241	unsigned long long value;
 
242
243	acpi_processor_errata();
244
245	/*
246	 * Check to see if we have bus mastering arbitration control.  This
247	 * is required for proper C3 usage (to maintain cache coherency).
248	 */
249	if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
250		pr->flags.bm_control = 1;
251		dev_dbg(&device->dev, "Bus mastering arbitration control present\n");
252	} else
253		dev_dbg(&device->dev, "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		 */
270		status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
271						NULL, &value);
272		if (ACPI_FAILURE(status)) {
273			dev_err(&device->dev,
274				"Failed to evaluate processor _UID (0x%x)\n",
275				status);
276			return -ENODEV;
277		}
278		device_declaration = 1;
279		pr->acpi_id = value;
280	}
281
282	if (acpi_duplicate_processor_id(pr->acpi_id)) {
283		if (pr->acpi_id == 0xff)
284			dev_info_once(&device->dev,
285				"Entry not well-defined, consider updating BIOS\n");
286		else
287			dev_err(&device->dev,
288				"Failed to get unique processor _UID (0x%x)\n",
289				pr->acpi_id);
290		return -ENODEV;
291	}
292
293	pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
294					pr->acpi_id);
295	if (invalid_phys_cpuid(pr->phys_id))
296		dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");
297
298	pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
299	if (!cpu0_initialized) {
300		cpu0_initialized = 1;
301		/*
302		 * Handle UP system running SMP kernel, with no CPU
303		 * entry in MADT
304		 */
305		if (!acpi_has_cpu_in_madt() && invalid_logical_cpuid(pr->id) &&
306		    (num_online_cpus() == 1))
307			pr->id = 0;
308		/*
309		 * Check availability of Processor Performance Control by
310		 * looking at the presence of the _PCT object under the first
311		 * processor definition.
312		 */
313		if (acpi_has_method(pr->handle, "_PCT"))
314			cpufreq_add_device("acpi-cpufreq");
315	}
316
317	/*
318	 *  Extra Processor objects may be enumerated on MP systems with
319	 *  less than the max # of CPUs. They should be ignored _iff
320	 *  they are physically not present.
321	 *
322	 *  NOTE: Even if the processor has a cpuid, it may not be present
323	 *  because cpuid <-> apicid mapping is persistent now.
324	 */
325	if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
326		int ret = acpi_processor_hotadd_init(pr);
327
328		if (ret)
329			return ret;
330	}
331
332	/*
333	 * On some boxes several processors use the same processor bus id.
334	 * But they are located in different scope. For example:
335	 * \_SB.SCK0.CPU0
336	 * \_SB.SCK1.CPU0
337	 * Rename the processor device bus id. And the new bus id will be
338	 * generated as the following format:
339	 * CPU+CPU ID.
340	 */
341	sprintf(acpi_device_bid(device), "CPU%X", pr->id);
342	dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);
343
344	if (!object.processor.pblk_address)
345		dev_dbg(&device->dev, "No PBLK (NULL address)\n");
346	else if (object.processor.pblk_length != 6)
347		dev_err(&device->dev, "Invalid PBLK length [%d]\n",
348			    object.processor.pblk_length);
349	else {
350		pr->throttling.address = object.processor.pblk_address;
351		pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
352		pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
353
354		pr->pblk = object.processor.pblk_address;
355	}
356
357	/*
358	 * If ACPI describes a slot number for this CPU, we can use it to
359	 * ensure we get the right value in the "physical id" field
360	 * of /proc/cpuinfo
361	 */
362	status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
363	if (ACPI_SUCCESS(status))
364		arch_fix_phys_package_id(pr->id, value);
365
366	return 0;
367}
368
369/*
370 * Do not put anything in here which needs the core to be online.
371 * For example MSR access or setting up things which check for cpuinfo_x86
372 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
373 * Such things have to be put in and set up by the processor driver's .probe().
374 */
375static DEFINE_PER_CPU(void *, processor_device_array);
376
377static int acpi_processor_add(struct acpi_device *device,
378					const struct acpi_device_id *id)
379{
380	struct acpi_processor *pr;
381	struct device *dev;
382	int result = 0;
383
 
 
 
384	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
385	if (!pr)
386		return -ENOMEM;
387
388	if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
389		result = -ENOMEM;
390		goto err_free_pr;
391	}
392
393	pr->handle = device->handle;
394	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
395	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
396	device->driver_data = pr;
397
398	result = acpi_processor_get_info(device);
399	if (result) /* Processor is not physically present or unavailable */
400		return 0;
401
402	BUG_ON(pr->id >= nr_cpu_ids);
403
404	/*
405	 * Buggy BIOS check.
406	 * ACPI id of processors can be reported wrongly by the BIOS.
407	 * Don't trust it blindly
408	 */
409	if (per_cpu(processor_device_array, pr->id) != NULL &&
410	    per_cpu(processor_device_array, pr->id) != device) {
411		dev_warn(&device->dev,
412			"BIOS reported wrong ACPI id %d for the processor\n",
413			pr->id);
414		/* Give up, but do not abort the namespace scan. */
415		goto err;
416	}
417	/*
418	 * processor_device_array is not cleared on errors to allow buggy BIOS
419	 * checks.
420	 */
421	per_cpu(processor_device_array, pr->id) = device;
422	per_cpu(processors, pr->id) = pr;
423
424	dev = get_cpu_device(pr->id);
425	if (!dev) {
426		result = -ENODEV;
427		goto err;
428	}
429
430	result = acpi_bind_one(dev, device);
431	if (result)
432		goto err;
433
434	pr->dev = dev;
435
436	/* Trigger the processor driver's .probe() if present. */
437	if (device_attach(dev) >= 0)
438		return 1;
439
440	dev_err(dev, "Processor driver could not be attached\n");
441	acpi_unbind_one(dev);
442
443 err:
 
 
 
444	free_cpumask_var(pr->throttling.shared_cpu_map);
445	device->driver_data = NULL;
446	per_cpu(processors, pr->id) = NULL;
447 err_free_pr:
448	kfree(pr);
449	return result;
450}
451
452#ifdef CONFIG_ACPI_HOTPLUG_CPU
453/* Removal */
454static void acpi_processor_remove(struct acpi_device *device)
455{
456	struct acpi_processor *pr;
457
458	if (!device || !acpi_driver_data(device))
459		return;
460
461	pr = acpi_driver_data(device);
462	if (pr->id >= nr_cpu_ids)
463		goto out;
464
465	/*
466	 * The only reason why we ever get here is CPU hot-removal.  The CPU is
467	 * already offline and the ACPI device removal locking prevents it from
468	 * being put back online at this point.
469	 *
470	 * Unbind the driver from the processor device and detach it from the
471	 * ACPI companion object.
472	 */
473	device_release_driver(pr->dev);
474	acpi_unbind_one(pr->dev);
475
476	/* Clean up. */
477	per_cpu(processor_device_array, pr->id) = NULL;
478	per_cpu(processors, pr->id) = NULL;
479
480	cpu_maps_update_begin();
481	cpus_write_lock();
482
483	/* Remove the CPU. */
484	arch_unregister_cpu(pr->id);
485	acpi_unmap_cpu(pr->id);
486
 
 
 
 
487	cpus_write_unlock();
488	cpu_maps_update_done();
489
490	try_offline_node(cpu_to_node(pr->id));
491
492 out:
493	free_cpumask_var(pr->throttling.shared_cpu_map);
494	kfree(pr);
495}
496#endif /* CONFIG_ACPI_HOTPLUG_CPU */
497
498#ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
499bool __init processor_physically_present(acpi_handle handle)
500{
501	int cpuid, type;
502	u32 acpi_id;
503	acpi_status status;
504	acpi_object_type acpi_type;
505	unsigned long long tmp;
506	union acpi_object object = {};
507	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
508
509	status = acpi_get_type(handle, &acpi_type);
510	if (ACPI_FAILURE(status))
511		return false;
512
513	switch (acpi_type) {
514	case ACPI_TYPE_PROCESSOR:
515		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
516		if (ACPI_FAILURE(status))
517			return false;
518		acpi_id = object.processor.proc_id;
519		break;
520	case ACPI_TYPE_DEVICE:
521		status = acpi_evaluate_integer(handle, METHOD_NAME__UID,
522					       NULL, &tmp);
523		if (ACPI_FAILURE(status))
524			return false;
525		acpi_id = tmp;
526		break;
527	default:
528		return false;
529	}
530
531	if (xen_initial_domain())
532		/*
533		 * When running as a Xen dom0 the number of processors Linux
534		 * sees can be different from the real number of processors on
535		 * the system, and we still need to execute _PDC or _OSC for
536		 * all of them.
537		 */
538		return xen_processor_present(acpi_id);
539
540	type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
541	cpuid = acpi_get_cpuid(handle, type, acpi_id);
542
543	return !invalid_logical_cpuid(cpuid);
544}
545
546/* vendor specific UUID indicating an Intel platform */
547static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
548
549static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl,
550					     void *context, void **rv)
551{
552	u32 capbuf[2] = {};
553	struct acpi_osc_context osc_context = {
554		.uuid_str = sb_uuid_str,
555		.rev = 1,
556		.cap.length = 8,
557		.cap.pointer = capbuf,
558	};
559	acpi_status status;
560
561	if (!processor_physically_present(handle))
562		return AE_OK;
563
564	arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]);
565
566	status = acpi_run_osc(handle, &osc_context);
567	if (ACPI_FAILURE(status))
568		return status;
569
570	kfree(osc_context.ret.pointer);
571
572	return AE_OK;
573}
574
575static bool __init acpi_early_processor_osc(void)
576{
577	acpi_status status;
578
579	acpi_proc_quirk_mwait_check();
580
581	status = acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
582				     ACPI_UINT32_MAX, acpi_processor_osc, NULL,
583				     NULL, NULL);
584	if (ACPI_FAILURE(status))
585		return false;
586
587	status = acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_osc,
588				  NULL, NULL);
589	if (ACPI_FAILURE(status))
590		return false;
591
592	return true;
593}
594
595void __init acpi_early_processor_control_setup(void)
596{
597	if (acpi_early_processor_osc()) {
598		pr_info("_OSC evaluated successfully for all CPUs\n");
599	} else {
600		pr_info("_OSC evaluation for CPUs failed, trying _PDC\n");
601		acpi_early_processor_set_pdc();
602	}
603}
604#endif
605
606/*
607 * The following ACPI IDs are known to be suitable for representing as
608 * processor devices.
609 */
610static const struct acpi_device_id processor_device_ids[] = {
611
612	{ ACPI_PROCESSOR_OBJECT_HID, },
613	{ ACPI_PROCESSOR_DEVICE_HID, },
614
615	{ }
616};
617
618static struct acpi_scan_handler processor_handler = {
619	.ids = processor_device_ids,
620	.attach = acpi_processor_add,
621#ifdef CONFIG_ACPI_HOTPLUG_CPU
622	.detach = acpi_processor_remove,
623#endif
624	.hotplug = {
625		.enabled = true,
626	},
627};
628
629static int acpi_processor_container_attach(struct acpi_device *dev,
630					   const struct acpi_device_id *id)
631{
632	return 1;
633}
634
635static const struct acpi_device_id processor_container_ids[] = {
636	{ ACPI_PROCESSOR_CONTAINER_HID, },
637	{ }
638};
639
640static struct acpi_scan_handler processor_container_handler = {
641	.ids = processor_container_ids,
642	.attach = acpi_processor_container_attach,
643};
644
645/* The number of the unique processor IDs */
646static int nr_unique_ids __initdata;
647
648/* The number of the duplicate processor IDs */
649static int nr_duplicate_ids;
650
651/* Used to store the unique processor IDs */
652static int unique_processor_ids[] __initdata = {
653	[0 ... NR_CPUS - 1] = -1,
654};
655
656/* Used to store the duplicate processor IDs */
657static int duplicate_processor_ids[] = {
658	[0 ... NR_CPUS - 1] = -1,
659};
660
661static void __init processor_validated_ids_update(int proc_id)
662{
663	int i;
664
665	if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
666		return;
667
668	/*
669	 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
670	 * already in the IDs, do nothing.
671	 */
672	for (i = 0; i < nr_duplicate_ids; i++) {
673		if (duplicate_processor_ids[i] == proc_id)
674			return;
675	}
676
677	/*
678	 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
679	 * the IDs, put it in the duplicate IDs.
680	 */
681	for (i = 0; i < nr_unique_ids; i++) {
682		if (unique_processor_ids[i] == proc_id) {
683			duplicate_processor_ids[nr_duplicate_ids] = proc_id;
684			nr_duplicate_ids++;
685			return;
686		}
687	}
688
689	/*
690	 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
691	 */
692	unique_processor_ids[nr_unique_ids] = proc_id;
693	nr_unique_ids++;
694}
695
696static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
697						  u32 lvl,
698						  void *context,
699						  void **rv)
700{
701	acpi_status status;
702	acpi_object_type acpi_type;
703	unsigned long long uid;
704	union acpi_object object = { 0 };
705	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
706
707	status = acpi_get_type(handle, &acpi_type);
708	if (ACPI_FAILURE(status))
709		return status;
710
711	switch (acpi_type) {
712	case ACPI_TYPE_PROCESSOR:
713		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
714		if (ACPI_FAILURE(status))
715			goto err;
716		uid = object.processor.proc_id;
717		break;
718
719	case ACPI_TYPE_DEVICE:
720		status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
721		if (ACPI_FAILURE(status))
722			goto err;
723		break;
724	default:
725		goto err;
726	}
727
728	processor_validated_ids_update(uid);
729	return AE_OK;
730
731err:
732	/* Exit on error, but don't abort the namespace walk */
733	acpi_handle_info(handle, "Invalid processor object\n");
734	return AE_OK;
735
736}
737
738static void __init acpi_processor_check_duplicates(void)
739{
740	/* check the correctness for all processors in ACPI namespace */
741	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
742						ACPI_UINT32_MAX,
743						acpi_processor_ids_walk,
744						NULL, NULL, NULL);
745	acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
746						NULL, NULL);
747}
748
749bool acpi_duplicate_processor_id(int proc_id)
750{
751	int i;
752
753	/*
754	 * compare the proc_id with duplicate IDs, if the proc_id is already
755	 * in the duplicate IDs, return true, otherwise, return false.
756	 */
757	for (i = 0; i < nr_duplicate_ids; i++) {
758		if (duplicate_processor_ids[i] == proc_id)
759			return true;
760	}
761	return false;
762}
763
764void __init acpi_processor_init(void)
765{
766	acpi_processor_check_duplicates();
767	acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
768	acpi_scan_add_handler(&processor_container_handler);
769	acpi_pcc_cpufreq_init();
770}
771
772#ifdef CONFIG_ACPI_PROCESSOR_CSTATE
773/**
774 * acpi_processor_claim_cst_control - Request _CST control from the platform.
775 */
776bool acpi_processor_claim_cst_control(void)
777{
778	static bool cst_control_claimed;
779	acpi_status status;
780
781	if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
782		return true;
783
784	status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
785				    acpi_gbl_FADT.cst_control, 8);
786	if (ACPI_FAILURE(status)) {
787		pr_warn("ACPI: Failed to claim processor _CST control\n");
788		return false;
789	}
790
791	cst_control_claimed = true;
792	return true;
793}
794EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
795
796/**
797 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
798 * @handle: ACPI handle of the processor object containing the _CST.
799 * @cpu: The numeric ID of the target CPU.
800 * @info: Object write the C-states information into.
801 *
802 * Extract the C-state information for the given CPU from the output of the _CST
803 * control method under the corresponding ACPI processor object (or processor
804 * device object) and populate @info with it.
805 *
806 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
807 * acpi_processor_ffh_cstate_probe() to verify them and update the
808 * cpu_cstate_entry data for @cpu.
809 */
810int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
811				struct acpi_processor_power *info)
812{
813	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
814	union acpi_object *cst;
815	acpi_status status;
816	u64 count;
817	int last_index = 0;
818	int i, ret = 0;
819
820	status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
821	if (ACPI_FAILURE(status)) {
822		acpi_handle_debug(handle, "No _CST\n");
823		return -ENODEV;
824	}
825
826	cst = buffer.pointer;
827
828	/* There must be at least 2 elements. */
829	if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
830		acpi_handle_warn(handle, "Invalid _CST output\n");
831		ret = -EFAULT;
832		goto end;
833	}
834
835	count = cst->package.elements[0].integer.value;
836
837	/* Validate the number of C-states. */
838	if (count < 1 || count != cst->package.count - 1) {
839		acpi_handle_warn(handle, "Inconsistent _CST data\n");
840		ret = -EFAULT;
841		goto end;
842	}
843
844	for (i = 1; i <= count; i++) {
845		union acpi_object *element;
846		union acpi_object *obj;
847		struct acpi_power_register *reg;
848		struct acpi_processor_cx cx;
849
850		/*
851		 * If there is not enough space for all C-states, skip the
852		 * excess ones and log a warning.
853		 */
854		if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
855			acpi_handle_warn(handle,
856					 "No room for more idle states (limit: %d)\n",
857					 ACPI_PROCESSOR_MAX_POWER - 1);
858			break;
859		}
860
861		memset(&cx, 0, sizeof(cx));
862
863		element = &cst->package.elements[i];
864		if (element->type != ACPI_TYPE_PACKAGE) {
865			acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
866					 i, element->type);
867			continue;
868		}
869
870		if (element->package.count != 4) {
871			acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
872					 i, element->package.count);
873			continue;
874		}
875
876		obj = &element->package.elements[0];
877
878		if (obj->type != ACPI_TYPE_BUFFER) {
879			acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
880					 i, obj->type);
881			continue;
882		}
883
884		reg = (struct acpi_power_register *)obj->buffer.pointer;
885
886		obj = &element->package.elements[1];
887		if (obj->type != ACPI_TYPE_INTEGER) {
888			acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
889					 i, obj->type);
890			continue;
891		}
892
893		cx.type = obj->integer.value;
894		/*
895		 * There are known cases in which the _CST output does not
896		 * contain C1, so if the type of the first state found is not
897		 * C1, leave an empty slot for C1 to be filled in later.
898		 */
899		if (i == 1 && cx.type != ACPI_STATE_C1)
900			last_index = 1;
901
902		cx.address = reg->address;
903		cx.index = last_index + 1;
904
905		if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
906			if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
907				/*
908				 * In the majority of cases _CST describes C1 as
909				 * a FIXED_HARDWARE C-state, but if the command
910				 * line forbids using MWAIT, use CSTATE_HALT for
911				 * C1 regardless.
912				 */
913				if (cx.type == ACPI_STATE_C1 &&
914				    boot_option_idle_override == IDLE_NOMWAIT) {
915					cx.entry_method = ACPI_CSTATE_HALT;
916					snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
917				} else {
918					cx.entry_method = ACPI_CSTATE_FFH;
919				}
920			} else if (cx.type == ACPI_STATE_C1) {
921				/*
922				 * In the special case of C1, FIXED_HARDWARE can
923				 * be handled by executing the HLT instruction.
924				 */
925				cx.entry_method = ACPI_CSTATE_HALT;
926				snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
927			} else {
928				acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
929						 i);
930				continue;
931			}
932		} else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
933			cx.entry_method = ACPI_CSTATE_SYSTEMIO;
934			snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
935				 cx.address);
936		} else {
937			acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
938					 i, reg->space_id);
939			continue;
940		}
941
942		if (cx.type == ACPI_STATE_C1)
943			cx.valid = 1;
944
945		obj = &element->package.elements[2];
946		if (obj->type != ACPI_TYPE_INTEGER) {
947			acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
948					 i, obj->type);
949			continue;
950		}
951
952		cx.latency = obj->integer.value;
953
954		obj = &element->package.elements[3];
955		if (obj->type != ACPI_TYPE_INTEGER) {
956			acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
957					 i, obj->type);
958			continue;
959		}
960
961		memcpy(&info->states[++last_index], &cx, sizeof(cx));
962	}
963
964	acpi_handle_info(handle, "Found %d idle states\n", last_index);
965
966	info->count = last_index;
967
968end:
969	kfree(buffer.pointer);
970
971	return ret;
972}
973EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
974#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */