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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 */