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
31 DEFINE_PER_CPU(struct acpi_processor *, processors);
32 EXPORT_PER_CPU_SYMBOL(processors);
33
34 /* Errata Handling */
35 struct acpi_processor_errata errata __read_mostly;
36 EXPORT_SYMBOL_GPL(errata);
37
acpi_processor_errata_piix4(struct pci_dev * dev)38 static 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
acpi_processor_errata(void)138 static 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. */
cpufreq_add_device(const char * name)158 static 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: %pe\n", name, pdev);
165 }
166
167 #ifdef CONFIG_X86
168 /* Check presence of Processor Clocking Control by searching for \_SB.PCCH. */
acpi_pcc_cpufreq_init(void)169 static 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
acpi_pcc_cpufreq_init(void)182 static void __init acpi_pcc_cpufreq_init(void) {}
183 #endif /* CONFIG_X86 */
184
185 /* Initialization */
186 #ifdef CONFIG_ACPI_HOTPLUG_CPU
acpi_processor_hotadd_init(struct acpi_processor * pr)187 static 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
221 out:
222 cpus_write_unlock();
223 cpu_maps_update_done();
224 return ret;
225 }
226 #else
acpi_processor_hotadd_init(struct acpi_processor * pr)227 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
228 {
229 return -ENODEV;
230 }
231 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
232
acpi_processor_get_info(struct acpi_device * device)233 static 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 */
375 static DEFINE_PER_CPU(void *, processor_device_array);
376
acpi_processor_add(struct acpi_device * device,const struct acpi_device_id * id)377 static 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 if (!acpi_device_is_enabled(device))
385 return -ENODEV;
386
387 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
388 if (!pr)
389 return -ENOMEM;
390
391 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
392 result = -ENOMEM;
393 goto err_free_pr;
394 }
395
396 pr->handle = device->handle;
397 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
398 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
399 device->driver_data = pr;
400
401 result = acpi_processor_get_info(device);
402 if (result) /* Processor is not physically present or unavailable */
403 return 0;
404
405 BUG_ON(pr->id >= nr_cpu_ids);
406
407 /*
408 * Buggy BIOS check.
409 * ACPI id of processors can be reported wrongly by the BIOS.
410 * Don't trust it blindly
411 */
412 if (per_cpu(processor_device_array, pr->id) != NULL &&
413 per_cpu(processor_device_array, pr->id) != device) {
414 dev_warn(&device->dev,
415 "BIOS reported wrong ACPI id %d for the processor\n",
416 pr->id);
417 /* Give up, but do not abort the namespace scan. */
418 goto err;
419 }
420 /*
421 * processor_device_array is not cleared on errors to allow buggy BIOS
422 * checks.
423 */
424 per_cpu(processor_device_array, pr->id) = device;
425 per_cpu(processors, pr->id) = pr;
426
427 dev = get_cpu_device(pr->id);
428 if (!dev) {
429 result = -ENODEV;
430 goto err;
431 }
432
433 result = acpi_bind_one(dev, device);
434 if (result)
435 goto err;
436
437 pr->dev = dev;
438
439 /* Trigger the processor driver's .probe() if present. */
440 if (device_attach(dev) >= 0)
441 return 1;
442
443 dev_err(dev, "Processor driver could not be attached\n");
444 acpi_unbind_one(dev);
445
446 err:
447 free_cpumask_var(pr->throttling.shared_cpu_map);
448 device->driver_data = NULL;
449 per_cpu(processors, pr->id) = NULL;
450 err_free_pr:
451 kfree(pr);
452 return result;
453 }
454
455 #ifdef CONFIG_ACPI_HOTPLUG_CPU
456 /* Removal */
acpi_processor_remove(struct acpi_device * device)457 static void acpi_processor_remove(struct acpi_device *device)
458 {
459 struct acpi_processor *pr;
460
461 if (!device || !acpi_driver_data(device))
462 return;
463
464 pr = acpi_driver_data(device);
465 if (pr->id >= nr_cpu_ids)
466 goto out;
467
468 /*
469 * The only reason why we ever get here is CPU hot-removal. The CPU is
470 * already offline and the ACPI device removal locking prevents it from
471 * being put back online at this point.
472 *
473 * Unbind the driver from the processor device and detach it from the
474 * ACPI companion object.
475 */
476 device_release_driver(pr->dev);
477 acpi_unbind_one(pr->dev);
478
479 /* Clean up. */
480 per_cpu(processor_device_array, pr->id) = NULL;
481 per_cpu(processors, pr->id) = NULL;
482
483 cpu_maps_update_begin();
484 cpus_write_lock();
485
486 /* Remove the CPU. */
487 arch_unregister_cpu(pr->id);
488 acpi_unmap_cpu(pr->id);
489
490 cpus_write_unlock();
491 cpu_maps_update_done();
492
493 try_offline_node(cpu_to_node(pr->id));
494
495 out:
496 free_cpumask_var(pr->throttling.shared_cpu_map);
497 kfree(pr);
498 }
499 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
500
501 #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
processor_physically_present(acpi_handle handle)502 bool __init processor_physically_present(acpi_handle handle)
503 {
504 int cpuid, type;
505 u32 acpi_id;
506 acpi_status status;
507 acpi_object_type acpi_type;
508 unsigned long long tmp;
509 union acpi_object object = {};
510 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
511
512 status = acpi_get_type(handle, &acpi_type);
513 if (ACPI_FAILURE(status))
514 return false;
515
516 switch (acpi_type) {
517 case ACPI_TYPE_PROCESSOR:
518 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
519 if (ACPI_FAILURE(status))
520 return false;
521 acpi_id = object.processor.proc_id;
522 break;
523 case ACPI_TYPE_DEVICE:
524 status = acpi_evaluate_integer(handle, METHOD_NAME__UID,
525 NULL, &tmp);
526 if (ACPI_FAILURE(status))
527 return false;
528 acpi_id = tmp;
529 break;
530 default:
531 return false;
532 }
533
534 if (xen_initial_domain())
535 /*
536 * When running as a Xen dom0 the number of processors Linux
537 * sees can be different from the real number of processors on
538 * the system, and we still need to execute _PDC or _OSC for
539 * all of them.
540 */
541 return xen_processor_present(acpi_id);
542
543 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
544 cpuid = acpi_get_cpuid(handle, type, acpi_id);
545
546 return !invalid_logical_cpuid(cpuid);
547 }
548
549 /* vendor specific UUID indicating an Intel platform */
550 static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
551
acpi_processor_osc(acpi_handle handle,u32 lvl,void * context,void ** rv)552 static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl,
553 void *context, void **rv)
554 {
555 u32 capbuf[2] = {};
556 struct acpi_osc_context osc_context = {
557 .uuid_str = sb_uuid_str,
558 .rev = 1,
559 .cap.length = 8,
560 .cap.pointer = capbuf,
561 };
562 acpi_status status;
563
564 if (!processor_physically_present(handle))
565 return AE_OK;
566
567 arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]);
568
569 status = acpi_run_osc(handle, &osc_context);
570 if (ACPI_FAILURE(status))
571 return status;
572
573 kfree(osc_context.ret.pointer);
574
575 return AE_OK;
576 }
577
acpi_early_processor_osc(void)578 static bool __init acpi_early_processor_osc(void)
579 {
580 acpi_status status;
581
582 acpi_proc_quirk_mwait_check();
583
584 status = acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
585 ACPI_UINT32_MAX, acpi_processor_osc, NULL,
586 NULL, NULL);
587 if (ACPI_FAILURE(status))
588 return false;
589
590 status = acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_osc,
591 NULL, NULL);
592 if (ACPI_FAILURE(status))
593 return false;
594
595 return true;
596 }
597
acpi_early_processor_control_setup(void)598 void __init acpi_early_processor_control_setup(void)
599 {
600 if (acpi_early_processor_osc()) {
601 pr_info("_OSC evaluated successfully for all CPUs\n");
602 } else {
603 pr_info("_OSC evaluation for CPUs failed, trying _PDC\n");
604 acpi_early_processor_set_pdc();
605 }
606 }
607 #endif
608
609 /*
610 * The following ACPI IDs are known to be suitable for representing as
611 * processor devices.
612 */
613 static const struct acpi_device_id processor_device_ids[] = {
614
615 { ACPI_PROCESSOR_OBJECT_HID, },
616 { ACPI_PROCESSOR_DEVICE_HID, },
617
618 { }
619 };
620
621 static struct acpi_scan_handler processor_handler = {
622 .ids = processor_device_ids,
623 .attach = acpi_processor_add,
624 #ifdef CONFIG_ACPI_HOTPLUG_CPU
625 .detach = acpi_processor_remove,
626 #endif
627 .hotplug = {
628 .enabled = true,
629 },
630 };
631
acpi_processor_container_attach(struct acpi_device * dev,const struct acpi_device_id * id)632 static int acpi_processor_container_attach(struct acpi_device *dev,
633 const struct acpi_device_id *id)
634 {
635 return 1;
636 }
637
638 static const struct acpi_device_id processor_container_ids[] = {
639 { ACPI_PROCESSOR_CONTAINER_HID, },
640 { }
641 };
642
643 static struct acpi_scan_handler processor_container_handler = {
644 .ids = processor_container_ids,
645 .attach = acpi_processor_container_attach,
646 };
647
648 /* The number of the unique processor IDs */
649 static int nr_unique_ids __initdata;
650
651 /* The number of the duplicate processor IDs */
652 static int nr_duplicate_ids;
653
654 /* Used to store the unique processor IDs */
655 static int unique_processor_ids[] __initdata = {
656 [0 ... NR_CPUS - 1] = -1,
657 };
658
659 /* Used to store the duplicate processor IDs */
660 static int duplicate_processor_ids[] = {
661 [0 ... NR_CPUS - 1] = -1,
662 };
663
processor_validated_ids_update(int proc_id)664 static void __init processor_validated_ids_update(int proc_id)
665 {
666 int i;
667
668 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
669 return;
670
671 /*
672 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
673 * already in the IDs, do nothing.
674 */
675 for (i = 0; i < nr_duplicate_ids; i++) {
676 if (duplicate_processor_ids[i] == proc_id)
677 return;
678 }
679
680 /*
681 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
682 * the IDs, put it in the duplicate IDs.
683 */
684 for (i = 0; i < nr_unique_ids; i++) {
685 if (unique_processor_ids[i] == proc_id) {
686 duplicate_processor_ids[nr_duplicate_ids] = proc_id;
687 nr_duplicate_ids++;
688 return;
689 }
690 }
691
692 /*
693 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
694 */
695 unique_processor_ids[nr_unique_ids] = proc_id;
696 nr_unique_ids++;
697 }
698
acpi_processor_ids_walk(acpi_handle handle,u32 lvl,void * context,void ** rv)699 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
700 u32 lvl,
701 void *context,
702 void **rv)
703 {
704 acpi_status status;
705 acpi_object_type acpi_type;
706 unsigned long long uid;
707 union acpi_object object = { 0 };
708 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
709
710 status = acpi_get_type(handle, &acpi_type);
711 if (ACPI_FAILURE(status))
712 return status;
713
714 switch (acpi_type) {
715 case ACPI_TYPE_PROCESSOR:
716 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
717 if (ACPI_FAILURE(status))
718 goto err;
719 uid = object.processor.proc_id;
720 break;
721
722 case ACPI_TYPE_DEVICE:
723 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
724 if (ACPI_FAILURE(status))
725 goto err;
726 break;
727 default:
728 goto err;
729 }
730
731 processor_validated_ids_update(uid);
732 return AE_OK;
733
734 err:
735 /* Exit on error, but don't abort the namespace walk */
736 acpi_handle_info(handle, "Invalid processor object\n");
737 return AE_OK;
738
739 }
740
acpi_processor_check_duplicates(void)741 static void __init acpi_processor_check_duplicates(void)
742 {
743 /* check the correctness for all processors in ACPI namespace */
744 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
745 ACPI_UINT32_MAX,
746 acpi_processor_ids_walk,
747 NULL, NULL, NULL);
748 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
749 NULL, NULL);
750 }
751
acpi_duplicate_processor_id(int proc_id)752 bool acpi_duplicate_processor_id(int proc_id)
753 {
754 int i;
755
756 /*
757 * compare the proc_id with duplicate IDs, if the proc_id is already
758 * in the duplicate IDs, return true, otherwise, return false.
759 */
760 for (i = 0; i < nr_duplicate_ids; i++) {
761 if (duplicate_processor_ids[i] == proc_id)
762 return true;
763 }
764 return false;
765 }
766
acpi_processor_init(void)767 void __init acpi_processor_init(void)
768 {
769 acpi_processor_check_duplicates();
770 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
771 acpi_scan_add_handler(&processor_container_handler);
772 acpi_pcc_cpufreq_init();
773 }
774
775 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
776 /**
777 * acpi_processor_claim_cst_control - Request _CST control from the platform.
778 */
acpi_processor_claim_cst_control(void)779 bool acpi_processor_claim_cst_control(void)
780 {
781 static bool cst_control_claimed;
782 acpi_status status;
783
784 if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
785 return true;
786
787 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
788 acpi_gbl_FADT.cst_control, 8);
789 if (ACPI_FAILURE(status)) {
790 pr_warn("ACPI: Failed to claim processor _CST control\n");
791 return false;
792 }
793
794 cst_control_claimed = true;
795 return true;
796 }
797 EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
798
799 /**
800 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
801 * @handle: ACPI handle of the processor object containing the _CST.
802 * @cpu: The numeric ID of the target CPU.
803 * @info: Object write the C-states information into.
804 *
805 * Extract the C-state information for the given CPU from the output of the _CST
806 * control method under the corresponding ACPI processor object (or processor
807 * device object) and populate @info with it.
808 *
809 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
810 * acpi_processor_ffh_cstate_probe() to verify them and update the
811 * cpu_cstate_entry data for @cpu.
812 */
acpi_processor_evaluate_cst(acpi_handle handle,u32 cpu,struct acpi_processor_power * info)813 int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
814 struct acpi_processor_power *info)
815 {
816 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
817 union acpi_object *cst;
818 acpi_status status;
819 u64 count;
820 int last_index = 0;
821 int i, ret = 0;
822
823 status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
824 if (ACPI_FAILURE(status)) {
825 acpi_handle_debug(handle, "No _CST\n");
826 return -ENODEV;
827 }
828
829 cst = buffer.pointer;
830
831 /* There must be at least 2 elements. */
832 if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
833 acpi_handle_warn(handle, "Invalid _CST output\n");
834 ret = -EFAULT;
835 goto end;
836 }
837
838 count = cst->package.elements[0].integer.value;
839
840 /* Validate the number of C-states. */
841 if (count < 1 || count != cst->package.count - 1) {
842 acpi_handle_warn(handle, "Inconsistent _CST data\n");
843 ret = -EFAULT;
844 goto end;
845 }
846
847 for (i = 1; i <= count; i++) {
848 union acpi_object *element;
849 union acpi_object *obj;
850 struct acpi_power_register *reg;
851 struct acpi_processor_cx cx;
852
853 /*
854 * If there is not enough space for all C-states, skip the
855 * excess ones and log a warning.
856 */
857 if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
858 acpi_handle_warn(handle,
859 "No room for more idle states (limit: %d)\n",
860 ACPI_PROCESSOR_MAX_POWER - 1);
861 break;
862 }
863
864 memset(&cx, 0, sizeof(cx));
865
866 element = &cst->package.elements[i];
867 if (element->type != ACPI_TYPE_PACKAGE) {
868 acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
869 i, element->type);
870 continue;
871 }
872
873 if (element->package.count != 4) {
874 acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
875 i, element->package.count);
876 continue;
877 }
878
879 obj = &element->package.elements[0];
880
881 if (obj->type != ACPI_TYPE_BUFFER) {
882 acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
883 i, obj->type);
884 continue;
885 }
886
887 reg = (struct acpi_power_register *)obj->buffer.pointer;
888
889 obj = &element->package.elements[1];
890 if (obj->type != ACPI_TYPE_INTEGER) {
891 acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
892 i, obj->type);
893 continue;
894 }
895
896 cx.type = obj->integer.value;
897 /*
898 * There are known cases in which the _CST output does not
899 * contain C1, so if the type of the first state found is not
900 * C1, leave an empty slot for C1 to be filled in later.
901 */
902 if (i == 1 && cx.type != ACPI_STATE_C1)
903 last_index = 1;
904
905 cx.address = reg->address;
906 cx.index = last_index + 1;
907
908 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
909 if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
910 /*
911 * In the majority of cases _CST describes C1 as
912 * a FIXED_HARDWARE C-state, but if the command
913 * line forbids using MWAIT, use CSTATE_HALT for
914 * C1 regardless.
915 */
916 if (cx.type == ACPI_STATE_C1 &&
917 boot_option_idle_override == IDLE_NOMWAIT) {
918 cx.entry_method = ACPI_CSTATE_HALT;
919 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
920 } else {
921 cx.entry_method = ACPI_CSTATE_FFH;
922 }
923 } else if (cx.type == ACPI_STATE_C1) {
924 /*
925 * In the special case of C1, FIXED_HARDWARE can
926 * be handled by executing the HLT instruction.
927 */
928 cx.entry_method = ACPI_CSTATE_HALT;
929 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
930 } else {
931 acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
932 i);
933 continue;
934 }
935 } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
936 cx.entry_method = ACPI_CSTATE_SYSTEMIO;
937 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
938 cx.address);
939 } else {
940 acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
941 i, reg->space_id);
942 continue;
943 }
944
945 if (cx.type == ACPI_STATE_C1)
946 cx.valid = 1;
947
948 obj = &element->package.elements[2];
949 if (obj->type != ACPI_TYPE_INTEGER) {
950 acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
951 i, obj->type);
952 continue;
953 }
954
955 cx.latency = obj->integer.value;
956
957 obj = &element->package.elements[3];
958 if (obj->type != ACPI_TYPE_INTEGER) {
959 acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
960 i, obj->type);
961 continue;
962 }
963
964 memcpy(&info->states[++last_index], &cx, sizeof(cx));
965 }
966
967 acpi_handle_info(handle, "Found %d idle states\n", last_index);
968
969 info->count = last_index;
970
971 end:
972 kfree(buffer.pointer);
973
974 return ret;
975 }
976 EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
977 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */
978