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v4.6
 
  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
 30ACPI_MODULE_NAME("processor");
 31
 32DEFINE_PER_CPU(struct acpi_processor *, processors);
 33EXPORT_PER_CPU_SYMBOL(processors);
 34
 35/* --------------------------------------------------------------------------
 36                                Errata Handling
 37   -------------------------------------------------------------------------- */
 38
 39struct acpi_processor_errata errata __read_mostly;
 40EXPORT_SYMBOL_GPL(errata);
 41
 42static 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
143static 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
167int __weak acpi_map_cpu(acpi_handle handle,
168		phys_cpuid_t physid, int *pcpu)
169{
170	return -ENODEV;
171}
172
173int __weak acpi_unmap_cpu(int cpu)
174{
175	return -ENODEV;
176}
177
178int __weak arch_register_cpu(int cpu)
179{
180	return -ENODEV;
181}
182
183void __weak arch_unregister_cpu(int cpu) {}
184
185static 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->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
219out:
220	cpu_hotplug_done();
221	cpu_maps_update_done();
222	return ret;
223}
224#else
225static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
226{
227	return -ENODEV;
228}
229#endif /* CONFIG_ACPI_HOTPLUG_CPU */
230
231static 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	pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
284					pr->acpi_id);
285	if (invalid_phys_cpuid(pr->phys_id))
286		acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
287
288	pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
289	if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
290		cpu0_initialized = 1;
291		/*
292		 * Handle UP system running SMP kernel, with no CPU
293		 * entry in MADT
294		 */
295		if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
296			pr->id = 0;
297	}
298
299	/*
300	 *  Extra Processor objects may be enumerated on MP systems with
301	 *  less than the max # of CPUs. They should be ignored _iff
302	 *  they are physically not present.
 
 
 
303	 */
304	if (invalid_logical_cpuid(pr->id)) {
305		int ret = acpi_processor_hotadd_init(pr);
 
306		if (ret)
307			return ret;
308	}
309
310	/*
311	 * On some boxes several processors use the same processor bus id.
312	 * But they are located in different scope. For example:
313	 * \_SB.SCK0.CPU0
314	 * \_SB.SCK1.CPU0
315	 * Rename the processor device bus id. And the new bus id will be
316	 * generated as the following format:
317	 * CPU+CPU ID.
318	 */
319	sprintf(acpi_device_bid(device), "CPU%X", pr->id);
320	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
321			  pr->acpi_id));
322
323	if (!object.processor.pblk_address)
324		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
325	else if (object.processor.pblk_length != 6)
326		dev_err(&device->dev, "Invalid PBLK length [%d]\n",
327			    object.processor.pblk_length);
328	else {
329		pr->throttling.address = object.processor.pblk_address;
330		pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
331		pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
332
333		pr->pblk = object.processor.pblk_address;
334
335		/*
336		 * We don't care about error returns - we just try to mark
337		 * these reserved so that nobody else is confused into thinking
338		 * that this region might be unused..
339		 *
340		 * (In particular, allocating the IO range for Cardbus)
341		 */
342		request_region(pr->throttling.address, 6, "ACPI CPU throttle");
343	}
344
345	/*
346	 * If ACPI describes a slot number for this CPU, we can use it to
347	 * ensure we get the right value in the "physical id" field
348	 * of /proc/cpuinfo
349	 */
350	status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
351	if (ACPI_SUCCESS(status))
352		arch_fix_phys_package_id(pr->id, value);
353
354	return 0;
355}
356
357/*
358 * Do not put anything in here which needs the core to be online.
359 * For example MSR access or setting up things which check for cpuinfo_x86
360 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
361 * Such things have to be put in and set up by the processor driver's .probe().
362 */
363static DEFINE_PER_CPU(void *, processor_device_array);
364
365static int acpi_processor_add(struct acpi_device *device,
366					const struct acpi_device_id *id)
367{
368	struct acpi_processor *pr;
369	struct device *dev;
370	int result = 0;
371
372	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
373	if (!pr)
374		return -ENOMEM;
375
376	if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
377		result = -ENOMEM;
378		goto err_free_pr;
379	}
380
381	pr->handle = device->handle;
382	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
383	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
384	device->driver_data = pr;
385
386	result = acpi_processor_get_info(device);
387	if (result) /* Processor is not physically present or unavailable */
388		return 0;
389
390#ifdef CONFIG_SMP
391	if (pr->id >= setup_max_cpus && pr->id != 0)
392		return 0;
393#endif
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
450static 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
495static bool acpi_hwp_native_thermal_lvt_set;
496static 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
532void __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 */
550static const struct acpi_device_id processor_device_ids[] = {
551
552	{ ACPI_PROCESSOR_OBJECT_HID, },
553	{ ACPI_PROCESSOR_DEVICE_HID, },
554
555	{ }
556};
557
558static 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
569static int acpi_processor_container_attach(struct acpi_device *dev,
570					   const struct acpi_device_id *id)
571{
572	return 1;
573}
574
575static const struct acpi_device_id processor_container_ids[] = {
576	{ ACPI_PROCESSOR_CONTAINER_HID, },
577	{ }
578};
579
580static struct acpi_scan_handler processor_container_handler = {
581	.ids = processor_container_ids,
582	.attach = acpi_processor_container_attach,
583};
584
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
585void __init acpi_processor_init(void)
586{
 
587	acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
588	acpi_scan_add_handler(&processor_container_handler);
589}
v5.14.15
  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
 
 
 
 
 25DEFINE_PER_CPU(struct acpi_processor *, processors);
 26EXPORT_PER_CPU_SYMBOL(processors);
 27
 28/* Errata Handling */
 
 
 
 29struct acpi_processor_errata errata __read_mostly;
 30EXPORT_SYMBOL_GPL(errata);
 31
 32static int acpi_processor_errata_piix4(struct pci_dev *dev)
 33{
 34	u8 value1 = 0;
 35	u8 value2 = 0;
 36
 37
 38	if (!dev)
 39		return -EINVAL;
 40
 41	/*
 42	 * Note that 'dev' references the PIIX4 ACPI Controller.
 43	 */
 44
 45	switch (dev->revision) {
 46	case 0:
 47		dev_dbg(&dev->dev, "Found PIIX4 A-step\n");
 48		break;
 49	case 1:
 50		dev_dbg(&dev->dev, "Found PIIX4 B-step\n");
 51		break;
 52	case 2:
 53		dev_dbg(&dev->dev, "Found PIIX4E\n");
 54		break;
 55	case 3:
 56		dev_dbg(&dev->dev, "Found PIIX4M\n");
 57		break;
 58	default:
 59		dev_dbg(&dev->dev, "Found unknown PIIX4\n");
 60		break;
 61	}
 62
 63	switch (dev->revision) {
 64
 65	case 0:		/* PIIX4 A-step */
 66	case 1:		/* PIIX4 B-step */
 67		/*
 68		 * See specification changes #13 ("Manual Throttle Duty Cycle")
 69		 * and #14 ("Enabling and Disabling Manual Throttle"), plus
 70		 * erratum #5 ("STPCLK# Deassertion Time") from the January
 71		 * 2002 PIIX4 specification update.  Applies to only older
 72		 * PIIX4 models.
 73		 */
 74		errata.piix4.throttle = 1;
 75		fallthrough;
 76
 77	case 2:		/* PIIX4E */
 78	case 3:		/* PIIX4M */
 79		/*
 80		 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
 81		 * Livelock") from the January 2002 PIIX4 specification update.
 82		 * Applies to all PIIX4 models.
 83		 */
 84
 85		/*
 86		 * BM-IDE
 87		 * ------
 88		 * Find the PIIX4 IDE Controller and get the Bus Master IDE
 89		 * Status register address.  We'll use this later to read
 90		 * each IDE controller's DMA status to make sure we catch all
 91		 * DMA activity.
 92		 */
 93		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
 94				     PCI_DEVICE_ID_INTEL_82371AB,
 95				     PCI_ANY_ID, PCI_ANY_ID, NULL);
 96		if (dev) {
 97			errata.piix4.bmisx = pci_resource_start(dev, 4);
 98			pci_dev_put(dev);
 99		}
100
101		/*
102		 * Type-F DMA
103		 * ----------
104		 * Find the PIIX4 ISA Controller and read the Motherboard
105		 * DMA controller's status to see if Type-F (Fast) DMA mode
106		 * is enabled (bit 7) on either channel.  Note that we'll
107		 * disable C3 support if this is enabled, as some legacy
108		 * devices won't operate well if fast DMA is disabled.
109		 */
110		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
111				     PCI_DEVICE_ID_INTEL_82371AB_0,
112				     PCI_ANY_ID, PCI_ANY_ID, NULL);
113		if (dev) {
114			pci_read_config_byte(dev, 0x76, &value1);
115			pci_read_config_byte(dev, 0x77, &value2);
116			if ((value1 & 0x80) || (value2 & 0x80))
117				errata.piix4.fdma = 1;
118			pci_dev_put(dev);
119		}
120
121		break;
122	}
123
124	if (errata.piix4.bmisx)
125		dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");
 
126	if (errata.piix4.fdma)
127		dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");
 
128
129	return 0;
130}
131
132static int acpi_processor_errata(void)
133{
134	int result = 0;
135	struct pci_dev *dev = NULL;
136
137	/*
138	 * PIIX4
139	 */
140	dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
141			     PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
142			     PCI_ANY_ID, NULL);
143	if (dev) {
144		result = acpi_processor_errata_piix4(dev);
145		pci_dev_put(dev);
146	}
147
148	return result;
149}
150
151/* Initialization */
 
 
 
152#ifdef CONFIG_ACPI_HOTPLUG_CPU
153int __weak acpi_map_cpu(acpi_handle handle,
154		phys_cpuid_t physid, u32 acpi_id, int *pcpu)
155{
156	return -ENODEV;
157}
158
159int __weak acpi_unmap_cpu(int cpu)
160{
161	return -ENODEV;
162}
163
164int __weak arch_register_cpu(int cpu)
165{
166	return -ENODEV;
167}
168
169void __weak arch_unregister_cpu(int cpu) {}
170
171static int acpi_processor_hotadd_init(struct acpi_processor *pr)
172{
173	unsigned long long sta;
174	acpi_status status;
175	int ret;
176
177	if (invalid_phys_cpuid(pr->phys_id))
178		return -ENODEV;
179
180	status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
181	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
182		return -ENODEV;
183
184	cpu_maps_update_begin();
185	cpu_hotplug_begin();
186
187	ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
188	if (ret)
189		goto out;
190
191	ret = arch_register_cpu(pr->id);
192	if (ret) {
193		acpi_unmap_cpu(pr->id);
194		goto out;
195	}
196
197	/*
198	 * CPU got hot-added, but cpu_data is not initialized yet.  Set a flag
199	 * to delay cpu_idle/throttling initialization and do it when the CPU
200	 * gets online for the first time.
201	 */
202	pr_info("CPU%d has been hot-added\n", pr->id);
203	pr->flags.need_hotplug_init = 1;
204
205out:
206	cpu_hotplug_done();
207	cpu_maps_update_done();
208	return ret;
209}
210#else
211static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
212{
213	return -ENODEV;
214}
215#endif /* CONFIG_ACPI_HOTPLUG_CPU */
216
217static int acpi_processor_get_info(struct acpi_device *device)
218{
219	union acpi_object object = { 0 };
220	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
221	struct acpi_processor *pr = acpi_driver_data(device);
222	int device_declaration = 0;
223	acpi_status status = AE_OK;
224	static int cpu0_initialized;
225	unsigned long long value;
226
227	acpi_processor_errata();
228
229	/*
230	 * Check to see if we have bus mastering arbitration control.  This
231	 * is required for proper C3 usage (to maintain cache coherency).
232	 */
233	if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
234		pr->flags.bm_control = 1;
235		dev_dbg(&device->dev, "Bus mastering arbitration control present\n");
 
236	} else
237		dev_dbg(&device->dev, "No bus mastering arbitration control\n");
 
238
239	if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
240		/* Declared with "Processor" statement; match ProcessorID */
241		status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
242		if (ACPI_FAILURE(status)) {
243			dev_err(&device->dev,
244				"Failed to evaluate processor object (0x%x)\n",
245				status);
246			return -ENODEV;
247		}
248
249		pr->acpi_id = object.processor.proc_id;
250	} else {
251		/*
252		 * Declared with "Device" statement; match _UID.
 
253		 */
254		status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
255						NULL, &value);
256		if (ACPI_FAILURE(status)) {
257			dev_err(&device->dev,
258				"Failed to evaluate processor _UID (0x%x)\n",
259				status);
260			return -ENODEV;
261		}
262		device_declaration = 1;
263		pr->acpi_id = value;
264	}
265
266	if (acpi_duplicate_processor_id(pr->acpi_id)) {
267		if (pr->acpi_id == 0xff)
268			dev_info_once(&device->dev,
269				"Entry not well-defined, consider updating BIOS\n");
270		else
271			dev_err(&device->dev,
272				"Failed to get unique processor _UID (0x%x)\n",
273				pr->acpi_id);
274		return -ENODEV;
275	}
276
277	pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
278					pr->acpi_id);
279	if (invalid_phys_cpuid(pr->phys_id))
280		dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");
281
282	pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
283	if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
284		cpu0_initialized = 1;
285		/*
286		 * Handle UP system running SMP kernel, with no CPU
287		 * entry in MADT
288		 */
289		if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
290			pr->id = 0;
291	}
292
293	/*
294	 *  Extra Processor objects may be enumerated on MP systems with
295	 *  less than the max # of CPUs. They should be ignored _iff
296	 *  they are physically not present.
297	 *
298	 *  NOTE: Even if the processor has a cpuid, it may not be present
299	 *  because cpuid <-> apicid mapping is persistent now.
300	 */
301	if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
302		int ret = acpi_processor_hotadd_init(pr);
303
304		if (ret)
305			return ret;
306	}
307
308	/*
309	 * On some boxes several processors use the same processor bus id.
310	 * But they are located in different scope. For example:
311	 * \_SB.SCK0.CPU0
312	 * \_SB.SCK1.CPU0
313	 * Rename the processor device bus id. And the new bus id will be
314	 * generated as the following format:
315	 * CPU+CPU ID.
316	 */
317	sprintf(acpi_device_bid(device), "CPU%X", pr->id);
318	dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);
 
319
320	if (!object.processor.pblk_address)
321		dev_dbg(&device->dev, "No PBLK (NULL address)\n");
322	else if (object.processor.pblk_length != 6)
323		dev_err(&device->dev, "Invalid PBLK length [%d]\n",
324			    object.processor.pblk_length);
325	else {
326		pr->throttling.address = object.processor.pblk_address;
327		pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
328		pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
329
330		pr->pblk = object.processor.pblk_address;
 
 
 
 
 
 
 
 
 
331	}
332
333	/*
334	 * If ACPI describes a slot number for this CPU, we can use it to
335	 * ensure we get the right value in the "physical id" field
336	 * of /proc/cpuinfo
337	 */
338	status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
339	if (ACPI_SUCCESS(status))
340		arch_fix_phys_package_id(pr->id, value);
341
342	return 0;
343}
344
345/*
346 * Do not put anything in here which needs the core to be online.
347 * For example MSR access or setting up things which check for cpuinfo_x86
348 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
349 * Such things have to be put in and set up by the processor driver's .probe().
350 */
351static DEFINE_PER_CPU(void *, processor_device_array);
352
353static int acpi_processor_add(struct acpi_device *device,
354					const struct acpi_device_id *id)
355{
356	struct acpi_processor *pr;
357	struct device *dev;
358	int result = 0;
359
360	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
361	if (!pr)
362		return -ENOMEM;
363
364	if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
365		result = -ENOMEM;
366		goto err_free_pr;
367	}
368
369	pr->handle = device->handle;
370	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
371	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
372	device->driver_data = pr;
373
374	result = acpi_processor_get_info(device);
375	if (result) /* Processor is not physically present or unavailable */
376		return 0;
377
 
 
 
 
 
378	BUG_ON(pr->id >= nr_cpu_ids);
379
380	/*
381	 * Buggy BIOS check.
382	 * ACPI id of processors can be reported wrongly by the BIOS.
383	 * Don't trust it blindly
384	 */
385	if (per_cpu(processor_device_array, pr->id) != NULL &&
386	    per_cpu(processor_device_array, pr->id) != device) {
387		dev_warn(&device->dev,
388			"BIOS reported wrong ACPI id %d for the processor\n",
389			pr->id);
390		/* Give up, but do not abort the namespace scan. */
391		goto err;
392	}
393	/*
394	 * processor_device_array is not cleared on errors to allow buggy BIOS
395	 * checks.
396	 */
397	per_cpu(processor_device_array, pr->id) = device;
398	per_cpu(processors, pr->id) = pr;
399
400	dev = get_cpu_device(pr->id);
401	if (!dev) {
402		result = -ENODEV;
403		goto err;
404	}
405
406	result = acpi_bind_one(dev, device);
407	if (result)
408		goto err;
409
410	pr->dev = dev;
411
412	/* Trigger the processor driver's .probe() if present. */
413	if (device_attach(dev) >= 0)
414		return 1;
415
416	dev_err(dev, "Processor driver could not be attached\n");
417	acpi_unbind_one(dev);
418
419 err:
420	free_cpumask_var(pr->throttling.shared_cpu_map);
421	device->driver_data = NULL;
422	per_cpu(processors, pr->id) = NULL;
423 err_free_pr:
424	kfree(pr);
425	return result;
426}
427
428#ifdef CONFIG_ACPI_HOTPLUG_CPU
429/* Removal */
 
 
 
430static void acpi_processor_remove(struct acpi_device *device)
431{
432	struct acpi_processor *pr;
433
434	if (!device || !acpi_driver_data(device))
435		return;
436
437	pr = acpi_driver_data(device);
438	if (pr->id >= nr_cpu_ids)
439		goto out;
440
441	/*
442	 * The only reason why we ever get here is CPU hot-removal.  The CPU is
443	 * already offline and the ACPI device removal locking prevents it from
444	 * being put back online at this point.
445	 *
446	 * Unbind the driver from the processor device and detach it from the
447	 * ACPI companion object.
448	 */
449	device_release_driver(pr->dev);
450	acpi_unbind_one(pr->dev);
451
452	/* Clean up. */
453	per_cpu(processor_device_array, pr->id) = NULL;
454	per_cpu(processors, pr->id) = NULL;
455
456	cpu_maps_update_begin();
457	cpu_hotplug_begin();
458
459	/* Remove the CPU. */
460	arch_unregister_cpu(pr->id);
461	acpi_unmap_cpu(pr->id);
462
463	cpu_hotplug_done();
464	cpu_maps_update_done();
465
466	try_offline_node(cpu_to_node(pr->id));
467
468 out:
469	free_cpumask_var(pr->throttling.shared_cpu_map);
470	kfree(pr);
471}
472#endif /* CONFIG_ACPI_HOTPLUG_CPU */
473
474#ifdef CONFIG_X86
475static bool acpi_hwp_native_thermal_lvt_set;
476static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
477							  u32 lvl,
478							  void *context,
479							  void **rv)
480{
481	u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
482	u32 capbuf[2];
483	struct acpi_osc_context osc_context = {
484		.uuid_str = sb_uuid_str,
485		.rev = 1,
486		.cap.length = 8,
487		.cap.pointer = capbuf,
488	};
489
490	if (acpi_hwp_native_thermal_lvt_set)
491		return AE_CTRL_TERMINATE;
492
493	capbuf[0] = 0x0000;
494	capbuf[1] = 0x1000; /* set bit 12 */
495
496	if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
497		if (osc_context.ret.pointer && osc_context.ret.length > 1) {
498			u32 *capbuf_ret = osc_context.ret.pointer;
499
500			if (capbuf_ret[1] & 0x1000) {
501				acpi_handle_info(handle,
502					"_OSC native thermal LVT Acked\n");
503				acpi_hwp_native_thermal_lvt_set = true;
504			}
505		}
506		kfree(osc_context.ret.pointer);
507	}
508
509	return AE_OK;
510}
511
512void __init acpi_early_processor_osc(void)
513{
514	if (boot_cpu_has(X86_FEATURE_HWP)) {
515		acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
516				    ACPI_UINT32_MAX,
517				    acpi_hwp_native_thermal_lvt_osc,
518				    NULL, NULL, NULL);
519		acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
520				 acpi_hwp_native_thermal_lvt_osc,
521				 NULL, NULL);
522	}
523}
524#endif
525
526/*
527 * The following ACPI IDs are known to be suitable for representing as
528 * processor devices.
529 */
530static const struct acpi_device_id processor_device_ids[] = {
531
532	{ ACPI_PROCESSOR_OBJECT_HID, },
533	{ ACPI_PROCESSOR_DEVICE_HID, },
534
535	{ }
536};
537
538static struct acpi_scan_handler processor_handler = {
539	.ids = processor_device_ids,
540	.attach = acpi_processor_add,
541#ifdef CONFIG_ACPI_HOTPLUG_CPU
542	.detach = acpi_processor_remove,
543#endif
544	.hotplug = {
545		.enabled = true,
546	},
547};
548
549static int acpi_processor_container_attach(struct acpi_device *dev,
550					   const struct acpi_device_id *id)
551{
552	return 1;
553}
554
555static const struct acpi_device_id processor_container_ids[] = {
556	{ ACPI_PROCESSOR_CONTAINER_HID, },
557	{ }
558};
559
560static struct acpi_scan_handler processor_container_handler = {
561	.ids = processor_container_ids,
562	.attach = acpi_processor_container_attach,
563};
564
565/* The number of the unique processor IDs */
566static int nr_unique_ids __initdata;
567
568/* The number of the duplicate processor IDs */
569static int nr_duplicate_ids;
570
571/* Used to store the unique processor IDs */
572static int unique_processor_ids[] __initdata = {
573	[0 ... NR_CPUS - 1] = -1,
574};
575
576/* Used to store the duplicate processor IDs */
577static int duplicate_processor_ids[] = {
578	[0 ... NR_CPUS - 1] = -1,
579};
580
581static void __init processor_validated_ids_update(int proc_id)
582{
583	int i;
584
585	if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
586		return;
587
588	/*
589	 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
590	 * already in the IDs, do nothing.
591	 */
592	for (i = 0; i < nr_duplicate_ids; i++) {
593		if (duplicate_processor_ids[i] == proc_id)
594			return;
595	}
596
597	/*
598	 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
599	 * the IDs, put it in the duplicate IDs.
600	 */
601	for (i = 0; i < nr_unique_ids; i++) {
602		if (unique_processor_ids[i] == proc_id) {
603			duplicate_processor_ids[nr_duplicate_ids] = proc_id;
604			nr_duplicate_ids++;
605			return;
606		}
607	}
608
609	/*
610	 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
611	 */
612	unique_processor_ids[nr_unique_ids] = proc_id;
613	nr_unique_ids++;
614}
615
616static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
617						  u32 lvl,
618						  void *context,
619						  void **rv)
620{
621	acpi_status status;
622	acpi_object_type acpi_type;
623	unsigned long long uid;
624	union acpi_object object = { 0 };
625	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
626
627	status = acpi_get_type(handle, &acpi_type);
628	if (ACPI_FAILURE(status))
629		return status;
630
631	switch (acpi_type) {
632	case ACPI_TYPE_PROCESSOR:
633		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
634		if (ACPI_FAILURE(status))
635			goto err;
636		uid = object.processor.proc_id;
637		break;
638
639	case ACPI_TYPE_DEVICE:
640		status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
641		if (ACPI_FAILURE(status))
642			goto err;
643		break;
644	default:
645		goto err;
646	}
647
648	processor_validated_ids_update(uid);
649	return AE_OK;
650
651err:
652	/* Exit on error, but don't abort the namespace walk */
653	acpi_handle_info(handle, "Invalid processor object\n");
654	return AE_OK;
655
656}
657
658static void __init acpi_processor_check_duplicates(void)
659{
660	/* check the correctness for all processors in ACPI namespace */
661	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
662						ACPI_UINT32_MAX,
663						acpi_processor_ids_walk,
664						NULL, NULL, NULL);
665	acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
666						NULL, NULL);
667}
668
669bool acpi_duplicate_processor_id(int proc_id)
670{
671	int i;
672
673	/*
674	 * compare the proc_id with duplicate IDs, if the proc_id is already
675	 * in the duplicate IDs, return true, otherwise, return false.
676	 */
677	for (i = 0; i < nr_duplicate_ids; i++) {
678		if (duplicate_processor_ids[i] == proc_id)
679			return true;
680	}
681	return false;
682}
683
684void __init acpi_processor_init(void)
685{
686	acpi_processor_check_duplicates();
687	acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
688	acpi_scan_add_handler(&processor_container_handler);
689}
690
691#ifdef CONFIG_ACPI_PROCESSOR_CSTATE
692/**
693 * acpi_processor_claim_cst_control - Request _CST control from the platform.
694 */
695bool acpi_processor_claim_cst_control(void)
696{
697	static bool cst_control_claimed;
698	acpi_status status;
699
700	if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
701		return true;
702
703	status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
704				    acpi_gbl_FADT.cst_control, 8);
705	if (ACPI_FAILURE(status)) {
706		pr_warn("ACPI: Failed to claim processor _CST control\n");
707		return false;
708	}
709
710	cst_control_claimed = true;
711	return true;
712}
713EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
714
715/**
716 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
717 * @handle: ACPI handle of the processor object containing the _CST.
718 * @cpu: The numeric ID of the target CPU.
719 * @info: Object write the C-states information into.
720 *
721 * Extract the C-state information for the given CPU from the output of the _CST
722 * control method under the corresponding ACPI processor object (or processor
723 * device object) and populate @info with it.
724 *
725 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
726 * acpi_processor_ffh_cstate_probe() to verify them and update the
727 * cpu_cstate_entry data for @cpu.
728 */
729int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
730				struct acpi_processor_power *info)
731{
732	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
733	union acpi_object *cst;
734	acpi_status status;
735	u64 count;
736	int last_index = 0;
737	int i, ret = 0;
738
739	status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
740	if (ACPI_FAILURE(status)) {
741		acpi_handle_debug(handle, "No _CST\n");
742		return -ENODEV;
743	}
744
745	cst = buffer.pointer;
746
747	/* There must be at least 2 elements. */
748	if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
749		acpi_handle_warn(handle, "Invalid _CST output\n");
750		ret = -EFAULT;
751		goto end;
752	}
753
754	count = cst->package.elements[0].integer.value;
755
756	/* Validate the number of C-states. */
757	if (count < 1 || count != cst->package.count - 1) {
758		acpi_handle_warn(handle, "Inconsistent _CST data\n");
759		ret = -EFAULT;
760		goto end;
761	}
762
763	for (i = 1; i <= count; i++) {
764		union acpi_object *element;
765		union acpi_object *obj;
766		struct acpi_power_register *reg;
767		struct acpi_processor_cx cx;
768
769		/*
770		 * If there is not enough space for all C-states, skip the
771		 * excess ones and log a warning.
772		 */
773		if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
774			acpi_handle_warn(handle,
775					 "No room for more idle states (limit: %d)\n",
776					 ACPI_PROCESSOR_MAX_POWER - 1);
777			break;
778		}
779
780		memset(&cx, 0, sizeof(cx));
781
782		element = &cst->package.elements[i];
783		if (element->type != ACPI_TYPE_PACKAGE) {
784			acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
785					 i, element->type);
786			continue;
787		}
788
789		if (element->package.count != 4) {
790			acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
791					 i, element->package.count);
792			continue;
793		}
794
795		obj = &element->package.elements[0];
796
797		if (obj->type != ACPI_TYPE_BUFFER) {
798			acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
799					 i, obj->type);
800			continue;
801		}
802
803		reg = (struct acpi_power_register *)obj->buffer.pointer;
804
805		obj = &element->package.elements[1];
806		if (obj->type != ACPI_TYPE_INTEGER) {
807			acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
808					 i, obj->type);
809			continue;
810		}
811
812		cx.type = obj->integer.value;
813		/*
814		 * There are known cases in which the _CST output does not
815		 * contain C1, so if the type of the first state found is not
816		 * C1, leave an empty slot for C1 to be filled in later.
817		 */
818		if (i == 1 && cx.type != ACPI_STATE_C1)
819			last_index = 1;
820
821		cx.address = reg->address;
822		cx.index = last_index + 1;
823
824		if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
825			if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
826				/*
827				 * In the majority of cases _CST describes C1 as
828				 * a FIXED_HARDWARE C-state, but if the command
829				 * line forbids using MWAIT, use CSTATE_HALT for
830				 * C1 regardless.
831				 */
832				if (cx.type == ACPI_STATE_C1 &&
833				    boot_option_idle_override == IDLE_NOMWAIT) {
834					cx.entry_method = ACPI_CSTATE_HALT;
835					snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
836				} else {
837					cx.entry_method = ACPI_CSTATE_FFH;
838				}
839			} else if (cx.type == ACPI_STATE_C1) {
840				/*
841				 * In the special case of C1, FIXED_HARDWARE can
842				 * be handled by executing the HLT instruction.
843				 */
844				cx.entry_method = ACPI_CSTATE_HALT;
845				snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
846			} else {
847				acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
848						 i);
849				continue;
850			}
851		} else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
852			cx.entry_method = ACPI_CSTATE_SYSTEMIO;
853			snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
854				 cx.address);
855		} else {
856			acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
857					 i, reg->space_id);
858			continue;
859		}
860
861		if (cx.type == ACPI_STATE_C1)
862			cx.valid = 1;
863
864		obj = &element->package.elements[2];
865		if (obj->type != ACPI_TYPE_INTEGER) {
866			acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
867					 i, obj->type);
868			continue;
869		}
870
871		cx.latency = obj->integer.value;
872
873		obj = &element->package.elements[3];
874		if (obj->type != ACPI_TYPE_INTEGER) {
875			acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
876					 i, obj->type);
877			continue;
878		}
879
880		memcpy(&info->states[++last_index], &cx, sizeof(cx));
881	}
882
883	acpi_handle_info(handle, "Found %d idle states\n", last_index);
884
885	info->count = last_index;
886
887end:
888	kfree(buffer.pointer);
889
890	return ret;
891}
892EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
893#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */