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_get_processor_handle(int cpu)38 acpi_handle acpi_get_processor_handle(int cpu)
39 {
40 struct acpi_processor *pr;
41
42 pr = per_cpu(processors, cpu);
43 if (pr)
44 return pr->handle;
45
46 return NULL;
47 }
48
acpi_processor_errata_piix4(struct pci_dev * dev)49 static int acpi_processor_errata_piix4(struct pci_dev *dev)
50 {
51 u8 value1 = 0;
52 u8 value2 = 0;
53
54
55 if (!dev)
56 return -EINVAL;
57
58 /*
59 * Note that 'dev' references the PIIX4 ACPI Controller.
60 */
61
62 switch (dev->revision) {
63 case 0:
64 dev_dbg(&dev->dev, "Found PIIX4 A-step\n");
65 break;
66 case 1:
67 dev_dbg(&dev->dev, "Found PIIX4 B-step\n");
68 break;
69 case 2:
70 dev_dbg(&dev->dev, "Found PIIX4E\n");
71 break;
72 case 3:
73 dev_dbg(&dev->dev, "Found PIIX4M\n");
74 break;
75 default:
76 dev_dbg(&dev->dev, "Found unknown PIIX4\n");
77 break;
78 }
79
80 switch (dev->revision) {
81
82 case 0: /* PIIX4 A-step */
83 case 1: /* PIIX4 B-step */
84 /*
85 * See specification changes #13 ("Manual Throttle Duty Cycle")
86 * and #14 ("Enabling and Disabling Manual Throttle"), plus
87 * erratum #5 ("STPCLK# Deassertion Time") from the January
88 * 2002 PIIX4 specification update. Applies to only older
89 * PIIX4 models.
90 */
91 errata.piix4.throttle = 1;
92 fallthrough;
93
94 case 2: /* PIIX4E */
95 case 3: /* PIIX4M */
96 /*
97 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
98 * Livelock") from the January 2002 PIIX4 specification update.
99 * Applies to all PIIX4 models.
100 */
101
102 /*
103 * BM-IDE
104 * ------
105 * Find the PIIX4 IDE Controller and get the Bus Master IDE
106 * Status register address. We'll use this later to read
107 * each IDE controller's DMA status to make sure we catch all
108 * DMA activity.
109 */
110 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
111 PCI_DEVICE_ID_INTEL_82371AB,
112 PCI_ANY_ID, PCI_ANY_ID, NULL);
113 if (dev) {
114 errata.piix4.bmisx = pci_resource_start(dev, 4);
115 pci_dev_put(dev);
116 }
117
118 /*
119 * Type-F DMA
120 * ----------
121 * Find the PIIX4 ISA Controller and read the Motherboard
122 * DMA controller's status to see if Type-F (Fast) DMA mode
123 * is enabled (bit 7) on either channel. Note that we'll
124 * disable C3 support if this is enabled, as some legacy
125 * devices won't operate well if fast DMA is disabled.
126 */
127 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
128 PCI_DEVICE_ID_INTEL_82371AB_0,
129 PCI_ANY_ID, PCI_ANY_ID, NULL);
130 if (dev) {
131 pci_read_config_byte(dev, 0x76, &value1);
132 pci_read_config_byte(dev, 0x77, &value2);
133 if ((value1 & 0x80) || (value2 & 0x80))
134 errata.piix4.fdma = 1;
135 pci_dev_put(dev);
136 }
137
138 break;
139 }
140
141 if (errata.piix4.bmisx)
142 dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");
143 if (errata.piix4.fdma)
144 dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");
145
146 return 0;
147 }
148
acpi_processor_errata(void)149 static int acpi_processor_errata(void)
150 {
151 int result = 0;
152 struct pci_dev *dev = NULL;
153
154 /*
155 * PIIX4
156 */
157 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
158 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
159 PCI_ANY_ID, NULL);
160 if (dev) {
161 result = acpi_processor_errata_piix4(dev);
162 pci_dev_put(dev);
163 }
164
165 return result;
166 }
167
168 /* Create a platform device to represent a CPU frequency control mechanism. */
cpufreq_add_device(const char * name)169 static void cpufreq_add_device(const char *name)
170 {
171 struct platform_device *pdev;
172
173 pdev = platform_device_register_simple(name, PLATFORM_DEVID_NONE, NULL, 0);
174 if (IS_ERR(pdev))
175 pr_info("%s device creation failed: %pe\n", name, pdev);
176 }
177
178 #ifdef CONFIG_X86
179 /* Check presence of Processor Clocking Control by searching for \_SB.PCCH. */
acpi_pcc_cpufreq_init(void)180 static void __init acpi_pcc_cpufreq_init(void)
181 {
182 acpi_status status;
183 acpi_handle handle;
184
185 status = acpi_get_handle(NULL, "\\_SB", &handle);
186 if (ACPI_FAILURE(status))
187 return;
188
189 if (acpi_has_method(handle, "PCCH"))
190 cpufreq_add_device("pcc-cpufreq");
191 }
192 #else
acpi_pcc_cpufreq_init(void)193 static void __init acpi_pcc_cpufreq_init(void) {}
194 #endif /* CONFIG_X86 */
195
196 /* Initialization */
197 static DEFINE_PER_CPU(void *, processor_device_array);
198
acpi_processor_set_per_cpu(struct acpi_processor * pr,struct acpi_device * device)199 static int acpi_processor_set_per_cpu(struct acpi_processor *pr,
200 struct acpi_device *device)
201 {
202 BUG_ON(pr->id >= nr_cpu_ids);
203
204 /*
205 * Buggy BIOS check.
206 * ACPI id of processors can be reported wrongly by the BIOS.
207 * Don't trust it blindly
208 */
209 if (per_cpu(processor_device_array, pr->id) != NULL &&
210 per_cpu(processor_device_array, pr->id) != device) {
211 dev_warn(&device->dev,
212 "BIOS reported wrong ACPI id %d for the processor\n",
213 pr->id);
214 return -EINVAL;
215 }
216 /*
217 * processor_device_array is not cleared on errors to allow buggy BIOS
218 * checks.
219 */
220 per_cpu(processor_device_array, pr->id) = device;
221 per_cpu(processors, pr->id) = pr;
222
223 return 0;
224 }
225
226 #ifdef CONFIG_ACPI_HOTPLUG_CPU
acpi_processor_hotadd_init(struct acpi_processor * pr,struct acpi_device * device)227 static int acpi_processor_hotadd_init(struct acpi_processor *pr,
228 struct acpi_device *device)
229 {
230 int ret;
231
232 if (invalid_phys_cpuid(pr->phys_id))
233 return -ENODEV;
234
235 cpu_maps_update_begin();
236 cpus_write_lock();
237
238 ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
239 if (ret)
240 goto out;
241
242 ret = acpi_processor_set_per_cpu(pr, device);
243 if (ret) {
244 acpi_unmap_cpu(pr->id);
245 goto out;
246 }
247
248 ret = arch_register_cpu(pr->id);
249 if (ret) {
250 /* Leave the processor device array in place to detect buggy bios */
251 per_cpu(processors, pr->id) = NULL;
252 acpi_unmap_cpu(pr->id);
253 goto out;
254 }
255
256 /*
257 * CPU got hot-added, but cpu_data is not initialized yet. Do
258 * cpu_idle/throttling initialization when the CPU gets online for
259 * the first time.
260 */
261 pr_info("CPU%d has been hot-added\n", pr->id);
262
263 out:
264 cpus_write_unlock();
265 cpu_maps_update_done();
266 return ret;
267 }
268 #else
acpi_processor_hotadd_init(struct acpi_processor * pr,struct acpi_device * device)269 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,
270 struct acpi_device *device)
271 {
272 return -ENODEV;
273 }
274 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
275
acpi_processor_get_info(struct acpi_device * device)276 static int acpi_processor_get_info(struct acpi_device *device)
277 {
278 union acpi_object object = { 0 };
279 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
280 struct acpi_processor *pr = acpi_driver_data(device);
281 int device_declaration = 0;
282 acpi_status status = AE_OK;
283 static int cpu0_initialized;
284 unsigned long long value;
285 int ret;
286
287 acpi_processor_errata();
288
289 /*
290 * Check to see if we have bus mastering arbitration control. This
291 * is required for proper C3 usage (to maintain cache coherency).
292 */
293 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
294 pr->flags.bm_control = 1;
295 dev_dbg(&device->dev, "Bus mastering arbitration control present\n");
296 } else
297 dev_dbg(&device->dev, "No bus mastering arbitration control\n");
298
299 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
300 /* Declared with "Processor" statement; match ProcessorID */
301 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
302 if (ACPI_FAILURE(status)) {
303 dev_err(&device->dev,
304 "Failed to evaluate processor object (0x%x)\n",
305 status);
306 return -ENODEV;
307 }
308
309 pr->acpi_id = object.processor.proc_id;
310 } else {
311 /*
312 * Declared with "Device" statement; match _UID.
313 */
314 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
315 NULL, &value);
316 if (ACPI_FAILURE(status)) {
317 dev_err(&device->dev,
318 "Failed to evaluate processor _UID (0x%x)\n",
319 status);
320 return -ENODEV;
321 }
322 device_declaration = 1;
323 pr->acpi_id = value;
324 }
325
326 if (acpi_duplicate_processor_id(pr->acpi_id)) {
327 if (pr->acpi_id == 0xff)
328 dev_info_once(&device->dev,
329 "Entry not well-defined, consider updating BIOS\n");
330 else
331 dev_err(&device->dev,
332 "Failed to get unique processor _UID (0x%x)\n",
333 pr->acpi_id);
334 return -ENODEV;
335 }
336
337 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
338 pr->acpi_id);
339 if (invalid_phys_cpuid(pr->phys_id))
340 dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");
341
342 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
343 if (!cpu0_initialized) {
344 cpu0_initialized = 1;
345 /*
346 * Handle UP system running SMP kernel, with no CPU
347 * entry in MADT
348 */
349 if (!acpi_has_cpu_in_madt() && invalid_logical_cpuid(pr->id) &&
350 (num_online_cpus() == 1))
351 pr->id = 0;
352 /*
353 * Check availability of Processor Performance Control by
354 * looking at the presence of the _PCT object under the first
355 * processor definition.
356 */
357 if (acpi_has_method(pr->handle, "_PCT"))
358 cpufreq_add_device("acpi-cpufreq");
359 }
360
361 /*
362 * This code is not called unless we know the CPU is present and
363 * enabled. The two paths are:
364 * a) Initially present CPUs on architectures that do not defer
365 * their arch_register_cpu() calls until this point.
366 * b) Hotplugged CPUs (enabled bit in _STA has transitioned from not
367 * enabled to enabled)
368 */
369 if (!get_cpu_device(pr->id))
370 ret = acpi_processor_hotadd_init(pr, device);
371 else
372 ret = acpi_processor_set_per_cpu(pr, device);
373 if (ret)
374 return ret;
375
376 /*
377 * On some boxes several processors use the same processor bus id.
378 * But they are located in different scope. For example:
379 * \_SB.SCK0.CPU0
380 * \_SB.SCK1.CPU0
381 * Rename the processor device bus id. And the new bus id will be
382 * generated as the following format:
383 * CPU+CPU ID.
384 */
385 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
386 dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);
387
388 if (!object.processor.pblk_address)
389 dev_dbg(&device->dev, "No PBLK (NULL address)\n");
390 else if (object.processor.pblk_length != 6)
391 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
392 object.processor.pblk_length);
393 else {
394 pr->throttling.address = object.processor.pblk_address;
395 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
396 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
397
398 pr->pblk = object.processor.pblk_address;
399 }
400
401 /*
402 * If ACPI describes a slot number for this CPU, we can use it to
403 * ensure we get the right value in the "physical id" field
404 * of /proc/cpuinfo
405 */
406 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
407 if (ACPI_SUCCESS(status))
408 arch_fix_phys_package_id(pr->id, value);
409
410 return 0;
411 }
412
413 /*
414 * Do not put anything in here which needs the core to be online.
415 * For example MSR access or setting up things which check for cpuinfo_x86
416 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
417 * Such things have to be put in and set up by the processor driver's .probe().
418 */
acpi_processor_add(struct acpi_device * device,const struct acpi_device_id * id)419 static int acpi_processor_add(struct acpi_device *device,
420 const struct acpi_device_id *id)
421 {
422 struct acpi_processor *pr;
423 struct device *dev;
424 int result = 0;
425
426 if (!acpi_device_is_enabled(device))
427 return -ENODEV;
428
429 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
430 if (!pr)
431 return -ENOMEM;
432
433 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
434 result = -ENOMEM;
435 goto err_free_pr;
436 }
437
438 pr->handle = device->handle;
439 strscpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
440 strscpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
441 device->driver_data = pr;
442
443 result = acpi_processor_get_info(device);
444 if (result) /* Processor is not physically present or unavailable */
445 goto err_clear_driver_data;
446
447 dev = get_cpu_device(pr->id);
448 if (!dev) {
449 result = -ENODEV;
450 goto err_clear_per_cpu;
451 }
452
453 result = acpi_bind_one(dev, device);
454 if (result)
455 goto err_clear_per_cpu;
456
457 pr->dev = dev;
458
459 /* Trigger the processor driver's .probe() if present. */
460 if (device_attach(dev) >= 0)
461 return 1;
462
463 dev_err(dev, "Processor driver could not be attached\n");
464 acpi_unbind_one(dev);
465
466 err_clear_per_cpu:
467 per_cpu(processors, pr->id) = NULL;
468 err_clear_driver_data:
469 device->driver_data = NULL;
470 free_cpumask_var(pr->throttling.shared_cpu_map);
471 err_free_pr:
472 kfree(pr);
473 return result;
474 }
475
476 #ifdef CONFIG_ACPI_HOTPLUG_CPU
477 /* Removal */
acpi_processor_post_eject(struct acpi_device * device)478 static void acpi_processor_post_eject(struct acpi_device *device)
479 {
480 struct acpi_processor *pr;
481
482 if (!device || !acpi_driver_data(device))
483 return;
484
485 pr = acpi_driver_data(device);
486 if (pr->id >= nr_cpu_ids)
487 goto out;
488
489 /*
490 * The only reason why we ever get here is CPU hot-removal. The CPU is
491 * already offline and the ACPI device removal locking prevents it from
492 * being put back online at this point.
493 *
494 * Unbind the driver from the processor device and detach it from the
495 * ACPI companion object.
496 */
497 device_release_driver(pr->dev);
498 acpi_unbind_one(pr->dev);
499
500 cpu_maps_update_begin();
501 cpus_write_lock();
502
503 /* Remove the CPU. */
504 arch_unregister_cpu(pr->id);
505 acpi_unmap_cpu(pr->id);
506
507 /* Clean up. */
508 per_cpu(processor_device_array, pr->id) = NULL;
509 per_cpu(processors, pr->id) = NULL;
510
511 cpus_write_unlock();
512 cpu_maps_update_done();
513
514 try_offline_node(cpu_to_node(pr->id));
515
516 out:
517 free_cpumask_var(pr->throttling.shared_cpu_map);
518 kfree(pr);
519 }
520 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
521
522 #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
processor_physically_present(acpi_handle handle)523 bool __init processor_physically_present(acpi_handle handle)
524 {
525 int cpuid, type;
526 u32 acpi_id;
527 acpi_status status;
528 acpi_object_type acpi_type;
529 unsigned long long tmp;
530 union acpi_object object = {};
531 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
532
533 status = acpi_get_type(handle, &acpi_type);
534 if (ACPI_FAILURE(status))
535 return false;
536
537 switch (acpi_type) {
538 case ACPI_TYPE_PROCESSOR:
539 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
540 if (ACPI_FAILURE(status))
541 return false;
542 acpi_id = object.processor.proc_id;
543 break;
544 case ACPI_TYPE_DEVICE:
545 status = acpi_evaluate_integer(handle, METHOD_NAME__UID,
546 NULL, &tmp);
547 if (ACPI_FAILURE(status))
548 return false;
549 acpi_id = tmp;
550 break;
551 default:
552 return false;
553 }
554
555 if (xen_initial_domain())
556 /*
557 * When running as a Xen dom0 the number of processors Linux
558 * sees can be different from the real number of processors on
559 * the system, and we still need to execute _PDC or _OSC for
560 * all of them.
561 */
562 return xen_processor_present(acpi_id);
563
564 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
565 cpuid = acpi_get_cpuid(handle, type, acpi_id);
566
567 return !invalid_logical_cpuid(cpuid);
568 }
569
570 /* vendor specific UUID indicating an Intel platform */
571 static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
572
acpi_processor_osc(acpi_handle handle,u32 lvl,void * context,void ** rv)573 static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl,
574 void *context, void **rv)
575 {
576 u32 capbuf[2] = {};
577 struct acpi_osc_context osc_context = {
578 .uuid_str = sb_uuid_str,
579 .rev = 1,
580 .cap.length = 8,
581 .cap.pointer = capbuf,
582 };
583 acpi_status status;
584
585 if (!processor_physically_present(handle))
586 return AE_OK;
587
588 arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]);
589
590 status = acpi_run_osc(handle, &osc_context);
591 if (ACPI_FAILURE(status))
592 return status;
593
594 kfree(osc_context.ret.pointer);
595
596 return AE_OK;
597 }
598
acpi_early_processor_osc(void)599 static bool __init acpi_early_processor_osc(void)
600 {
601 acpi_status status;
602
603 acpi_proc_quirk_mwait_check();
604
605 status = acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
606 ACPI_UINT32_MAX, acpi_processor_osc, NULL,
607 NULL, NULL);
608 if (ACPI_FAILURE(status))
609 return false;
610
611 status = acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_osc,
612 NULL, NULL);
613 if (ACPI_FAILURE(status))
614 return false;
615
616 return true;
617 }
618
acpi_early_processor_control_setup(void)619 void __init acpi_early_processor_control_setup(void)
620 {
621 if (acpi_early_processor_osc()) {
622 pr_debug("_OSC evaluated successfully for all CPUs\n");
623 } else {
624 pr_debug("_OSC evaluation for CPUs failed, trying _PDC\n");
625 acpi_early_processor_set_pdc();
626 }
627 }
628 #endif
629
630 /*
631 * The following ACPI IDs are known to be suitable for representing as
632 * processor devices.
633 */
634 static const struct acpi_device_id processor_device_ids[] = {
635
636 { ACPI_PROCESSOR_OBJECT_HID, },
637 { ACPI_PROCESSOR_DEVICE_HID, },
638
639 { }
640 };
641
642 static struct acpi_scan_handler processor_handler = {
643 .ids = processor_device_ids,
644 .attach = acpi_processor_add,
645 #ifdef CONFIG_ACPI_HOTPLUG_CPU
646 .post_eject = acpi_processor_post_eject,
647 #endif
648 .hotplug = {
649 .enabled = true,
650 },
651 };
652
acpi_processor_container_attach(struct acpi_device * dev,const struct acpi_device_id * id)653 static int acpi_processor_container_attach(struct acpi_device *dev,
654 const struct acpi_device_id *id)
655 {
656 return 1;
657 }
658
659 static const struct acpi_device_id processor_container_ids[] = {
660 { ACPI_PROCESSOR_CONTAINER_HID, },
661 { }
662 };
663
664 static struct acpi_scan_handler processor_container_handler = {
665 .ids = processor_container_ids,
666 .attach = acpi_processor_container_attach,
667 };
668
669 /* The number of the unique processor IDs */
670 static int nr_unique_ids __initdata;
671
672 /* The number of the duplicate processor IDs */
673 static int nr_duplicate_ids;
674
675 /* Used to store the unique processor IDs */
676 static int unique_processor_ids[] __initdata = {
677 [0 ... NR_CPUS - 1] = -1,
678 };
679
680 /* Used to store the duplicate processor IDs */
681 static int duplicate_processor_ids[] = {
682 [0 ... NR_CPUS - 1] = -1,
683 };
684
processor_validated_ids_update(int proc_id)685 static void __init processor_validated_ids_update(int proc_id)
686 {
687 int i;
688
689 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
690 return;
691
692 /*
693 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
694 * already in the IDs, do nothing.
695 */
696 for (i = 0; i < nr_duplicate_ids; i++) {
697 if (duplicate_processor_ids[i] == proc_id)
698 return;
699 }
700
701 /*
702 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
703 * the IDs, put it in the duplicate IDs.
704 */
705 for (i = 0; i < nr_unique_ids; i++) {
706 if (unique_processor_ids[i] == proc_id) {
707 duplicate_processor_ids[nr_duplicate_ids] = proc_id;
708 nr_duplicate_ids++;
709 return;
710 }
711 }
712
713 /*
714 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
715 */
716 unique_processor_ids[nr_unique_ids] = proc_id;
717 nr_unique_ids++;
718 }
719
acpi_processor_ids_walk(acpi_handle handle,u32 lvl,void * context,void ** rv)720 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
721 u32 lvl,
722 void *context,
723 void **rv)
724 {
725 acpi_status status;
726 acpi_object_type acpi_type;
727 unsigned long long uid;
728 union acpi_object object = { 0 };
729 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
730
731 status = acpi_get_type(handle, &acpi_type);
732 if (ACPI_FAILURE(status))
733 return status;
734
735 switch (acpi_type) {
736 case ACPI_TYPE_PROCESSOR:
737 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
738 if (ACPI_FAILURE(status))
739 goto err;
740 uid = object.processor.proc_id;
741 break;
742
743 case ACPI_TYPE_DEVICE:
744 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
745 if (ACPI_FAILURE(status))
746 goto err;
747 break;
748 default:
749 goto err;
750 }
751
752 processor_validated_ids_update(uid);
753 return AE_OK;
754
755 err:
756 /* Exit on error, but don't abort the namespace walk */
757 acpi_handle_info(handle, "Invalid processor object\n");
758 return AE_OK;
759
760 }
761
acpi_processor_check_duplicates(void)762 static void __init acpi_processor_check_duplicates(void)
763 {
764 /* check the correctness for all processors in ACPI namespace */
765 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
766 ACPI_UINT32_MAX,
767 acpi_processor_ids_walk,
768 NULL, NULL, NULL);
769 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
770 NULL, NULL);
771 }
772
acpi_duplicate_processor_id(int proc_id)773 bool acpi_duplicate_processor_id(int proc_id)
774 {
775 int i;
776
777 /*
778 * compare the proc_id with duplicate IDs, if the proc_id is already
779 * in the duplicate IDs, return true, otherwise, return false.
780 */
781 for (i = 0; i < nr_duplicate_ids; i++) {
782 if (duplicate_processor_ids[i] == proc_id)
783 return true;
784 }
785 return false;
786 }
787
acpi_processor_init(void)788 void __init acpi_processor_init(void)
789 {
790 acpi_processor_check_duplicates();
791 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
792 acpi_scan_add_handler(&processor_container_handler);
793 acpi_pcc_cpufreq_init();
794 }
795
796 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
797 /**
798 * acpi_processor_claim_cst_control - Request _CST control from the platform.
799 */
acpi_processor_claim_cst_control(void)800 bool acpi_processor_claim_cst_control(void)
801 {
802 static bool cst_control_claimed;
803 acpi_status status;
804
805 if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
806 return true;
807
808 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
809 acpi_gbl_FADT.cst_control, 8);
810 if (ACPI_FAILURE(status)) {
811 pr_warn("ACPI: Failed to claim processor _CST control\n");
812 return false;
813 }
814
815 cst_control_claimed = true;
816 return true;
817 }
818 EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
819
820 /**
821 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
822 * @handle: ACPI handle of the processor object containing the _CST.
823 * @cpu: The numeric ID of the target CPU.
824 * @info: Object write the C-states information into.
825 *
826 * Extract the C-state information for the given CPU from the output of the _CST
827 * control method under the corresponding ACPI processor object (or processor
828 * device object) and populate @info with it.
829 *
830 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
831 * acpi_processor_ffh_cstate_probe() to verify them and update the
832 * cpu_cstate_entry data for @cpu.
833 */
acpi_processor_evaluate_cst(acpi_handle handle,u32 cpu,struct acpi_processor_power * info)834 int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
835 struct acpi_processor_power *info)
836 {
837 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
838 union acpi_object *cst;
839 acpi_status status;
840 u64 count;
841 int last_index = 0;
842 int i, ret = 0;
843
844 status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
845 if (ACPI_FAILURE(status)) {
846 acpi_handle_debug(handle, "No _CST\n");
847 return -ENODEV;
848 }
849
850 cst = buffer.pointer;
851
852 /* There must be at least 2 elements. */
853 if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
854 acpi_handle_warn(handle, "Invalid _CST output\n");
855 ret = -EFAULT;
856 goto end;
857 }
858
859 count = cst->package.elements[0].integer.value;
860
861 /* Validate the number of C-states. */
862 if (count < 1 || count != cst->package.count - 1) {
863 acpi_handle_warn(handle, "Inconsistent _CST data\n");
864 ret = -EFAULT;
865 goto end;
866 }
867
868 for (i = 1; i <= count; i++) {
869 union acpi_object *element;
870 union acpi_object *obj;
871 struct acpi_power_register *reg;
872 struct acpi_processor_cx cx;
873
874 /*
875 * If there is not enough space for all C-states, skip the
876 * excess ones and log a warning.
877 */
878 if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
879 acpi_handle_warn(handle,
880 "No room for more idle states (limit: %d)\n",
881 ACPI_PROCESSOR_MAX_POWER - 1);
882 break;
883 }
884
885 memset(&cx, 0, sizeof(cx));
886
887 element = &cst->package.elements[i];
888 if (element->type != ACPI_TYPE_PACKAGE) {
889 acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
890 i, element->type);
891 continue;
892 }
893
894 if (element->package.count != 4) {
895 acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
896 i, element->package.count);
897 continue;
898 }
899
900 obj = &element->package.elements[0];
901
902 if (obj->type != ACPI_TYPE_BUFFER) {
903 acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
904 i, obj->type);
905 continue;
906 }
907
908 reg = (struct acpi_power_register *)obj->buffer.pointer;
909
910 obj = &element->package.elements[1];
911 if (obj->type != ACPI_TYPE_INTEGER) {
912 acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
913 i, obj->type);
914 continue;
915 }
916
917 cx.type = obj->integer.value;
918 /*
919 * There are known cases in which the _CST output does not
920 * contain C1, so if the type of the first state found is not
921 * C1, leave an empty slot for C1 to be filled in later.
922 */
923 if (i == 1 && cx.type != ACPI_STATE_C1)
924 last_index = 1;
925
926 cx.address = reg->address;
927 cx.index = last_index + 1;
928
929 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
930 if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
931 /*
932 * In the majority of cases _CST describes C1 as
933 * a FIXED_HARDWARE C-state, but if the command
934 * line forbids using MWAIT, use CSTATE_HALT for
935 * C1 regardless.
936 */
937 if (cx.type == ACPI_STATE_C1 &&
938 boot_option_idle_override == IDLE_NOMWAIT) {
939 cx.entry_method = ACPI_CSTATE_HALT;
940 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
941 } else {
942 cx.entry_method = ACPI_CSTATE_FFH;
943 }
944 } else if (cx.type == ACPI_STATE_C1) {
945 /*
946 * In the special case of C1, FIXED_HARDWARE can
947 * be handled by executing the HLT instruction.
948 */
949 cx.entry_method = ACPI_CSTATE_HALT;
950 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
951 } else {
952 acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
953 i);
954 continue;
955 }
956 } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
957 cx.entry_method = ACPI_CSTATE_SYSTEMIO;
958 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
959 cx.address);
960 } else {
961 acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
962 i, reg->space_id);
963 continue;
964 }
965
966 if (cx.type == ACPI_STATE_C1)
967 cx.valid = 1;
968
969 obj = &element->package.elements[2];
970 if (obj->type != ACPI_TYPE_INTEGER) {
971 acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
972 i, obj->type);
973 continue;
974 }
975
976 cx.latency = obj->integer.value;
977
978 obj = &element->package.elements[3];
979 if (obj->type != ACPI_TYPE_INTEGER) {
980 acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
981 i, obj->type);
982 continue;
983 }
984
985 memcpy(&info->states[++last_index], &cx, sizeof(cx));
986 }
987
988 acpi_handle_debug(handle, "Found %d idle states\n", last_index);
989
990 info->count = last_index;
991
992 end:
993 kfree(buffer.pointer);
994
995 return ret;
996 }
997 EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
998 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */
999