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
25 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
26
27 ACPI_MODULE_NAME("processor");
28
29 DEFINE_PER_CPU(struct acpi_processor *, processors);
30 EXPORT_PER_CPU_SYMBOL(processors);
31
32 /* --------------------------------------------------------------------------
33 Errata Handling
34 -------------------------------------------------------------------------- */
35
36 struct acpi_processor_errata errata __read_mostly;
37 EXPORT_SYMBOL_GPL(errata);
38
acpi_processor_errata_piix4(struct pci_dev * dev)39 static int acpi_processor_errata_piix4(struct pci_dev *dev)
40 {
41 u8 value1 = 0;
42 u8 value2 = 0;
43
44
45 if (!dev)
46 return -EINVAL;
47
48 /*
49 * Note that 'dev' references the PIIX4 ACPI Controller.
50 */
51
52 switch (dev->revision) {
53 case 0:
54 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
55 break;
56 case 1:
57 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
58 break;
59 case 2:
60 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
61 break;
62 case 3:
63 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
64 break;
65 default:
66 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
67 break;
68 }
69
70 switch (dev->revision) {
71
72 case 0: /* PIIX4 A-step */
73 case 1: /* PIIX4 B-step */
74 /*
75 * See specification changes #13 ("Manual Throttle Duty Cycle")
76 * and #14 ("Enabling and Disabling Manual Throttle"), plus
77 * erratum #5 ("STPCLK# Deassertion Time") from the January
78 * 2002 PIIX4 specification update. Applies to only older
79 * PIIX4 models.
80 */
81 errata.piix4.throttle = 1;
82 fallthrough;
83
84 case 2: /* PIIX4E */
85 case 3: /* PIIX4M */
86 /*
87 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
88 * Livelock") from the January 2002 PIIX4 specification update.
89 * Applies to all PIIX4 models.
90 */
91
92 /*
93 * BM-IDE
94 * ------
95 * Find the PIIX4 IDE Controller and get the Bus Master IDE
96 * Status register address. We'll use this later to read
97 * each IDE controller's DMA status to make sure we catch all
98 * DMA activity.
99 */
100 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
101 PCI_DEVICE_ID_INTEL_82371AB,
102 PCI_ANY_ID, PCI_ANY_ID, NULL);
103 if (dev) {
104 errata.piix4.bmisx = pci_resource_start(dev, 4);
105 pci_dev_put(dev);
106 }
107
108 /*
109 * Type-F DMA
110 * ----------
111 * Find the PIIX4 ISA Controller and read the Motherboard
112 * DMA controller's status to see if Type-F (Fast) DMA mode
113 * is enabled (bit 7) on either channel. Note that we'll
114 * disable C3 support if this is enabled, as some legacy
115 * devices won't operate well if fast DMA is disabled.
116 */
117 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
118 PCI_DEVICE_ID_INTEL_82371AB_0,
119 PCI_ANY_ID, PCI_ANY_ID, NULL);
120 if (dev) {
121 pci_read_config_byte(dev, 0x76, &value1);
122 pci_read_config_byte(dev, 0x77, &value2);
123 if ((value1 & 0x80) || (value2 & 0x80))
124 errata.piix4.fdma = 1;
125 pci_dev_put(dev);
126 }
127
128 break;
129 }
130
131 if (errata.piix4.bmisx)
132 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
133 "Bus master activity detection (BM-IDE) erratum enabled\n"));
134 if (errata.piix4.fdma)
135 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
136 "Type-F DMA livelock erratum (C3 disabled)\n"));
137
138 return 0;
139 }
140
acpi_processor_errata(void)141 static int acpi_processor_errata(void)
142 {
143 int result = 0;
144 struct pci_dev *dev = NULL;
145
146 /*
147 * PIIX4
148 */
149 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
150 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
151 PCI_ANY_ID, NULL);
152 if (dev) {
153 result = acpi_processor_errata_piix4(dev);
154 pci_dev_put(dev);
155 }
156
157 return result;
158 }
159
160 /* --------------------------------------------------------------------------
161 Initialization
162 -------------------------------------------------------------------------- */
163
164 #ifdef CONFIG_ACPI_HOTPLUG_CPU
acpi_map_cpu(acpi_handle handle,phys_cpuid_t physid,u32 acpi_id,int * pcpu)165 int __weak acpi_map_cpu(acpi_handle handle,
166 phys_cpuid_t physid, u32 acpi_id, int *pcpu)
167 {
168 return -ENODEV;
169 }
170
acpi_unmap_cpu(int cpu)171 int __weak acpi_unmap_cpu(int cpu)
172 {
173 return -ENODEV;
174 }
175
arch_register_cpu(int cpu)176 int __weak arch_register_cpu(int cpu)
177 {
178 return -ENODEV;
179 }
180
arch_unregister_cpu(int cpu)181 void __weak arch_unregister_cpu(int cpu) {}
182
acpi_processor_hotadd_init(struct acpi_processor * pr)183 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
184 {
185 unsigned long long sta;
186 acpi_status status;
187 int ret;
188
189 if (invalid_phys_cpuid(pr->phys_id))
190 return -ENODEV;
191
192 status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
193 if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
194 return -ENODEV;
195
196 cpu_maps_update_begin();
197 cpu_hotplug_begin();
198
199 ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
200 if (ret)
201 goto out;
202
203 ret = arch_register_cpu(pr->id);
204 if (ret) {
205 acpi_unmap_cpu(pr->id);
206 goto out;
207 }
208
209 /*
210 * CPU got hot-added, but cpu_data is not initialized yet. Set a flag
211 * to delay cpu_idle/throttling initialization and do it when the CPU
212 * gets online for the first time.
213 */
214 pr_info("CPU%d has been hot-added\n", pr->id);
215 pr->flags.need_hotplug_init = 1;
216
217 out:
218 cpu_hotplug_done();
219 cpu_maps_update_done();
220 return ret;
221 }
222 #else
acpi_processor_hotadd_init(struct acpi_processor * pr)223 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
224 {
225 return -ENODEV;
226 }
227 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
228
acpi_processor_get_info(struct acpi_device * device)229 static int acpi_processor_get_info(struct acpi_device *device)
230 {
231 union acpi_object object = { 0 };
232 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
233 struct acpi_processor *pr = acpi_driver_data(device);
234 int device_declaration = 0;
235 acpi_status status = AE_OK;
236 static int cpu0_initialized;
237 unsigned long long value;
238
239 acpi_processor_errata();
240
241 /*
242 * Check to see if we have bus mastering arbitration control. This
243 * is required for proper C3 usage (to maintain cache coherency).
244 */
245 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
246 pr->flags.bm_control = 1;
247 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
248 "Bus mastering arbitration control present\n"));
249 } else
250 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
251 "No bus mastering arbitration control\n"));
252
253 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
254 /* Declared with "Processor" statement; match ProcessorID */
255 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
256 if (ACPI_FAILURE(status)) {
257 dev_err(&device->dev,
258 "Failed to evaluate processor object (0x%x)\n",
259 status);
260 return -ENODEV;
261 }
262
263 pr->acpi_id = object.processor.proc_id;
264 } else {
265 /*
266 * Declared with "Device" statement; match _UID.
267 */
268 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
269 NULL, &value);
270 if (ACPI_FAILURE(status)) {
271 dev_err(&device->dev,
272 "Failed to evaluate processor _UID (0x%x)\n",
273 status);
274 return -ENODEV;
275 }
276 device_declaration = 1;
277 pr->acpi_id = value;
278 }
279
280 if (acpi_duplicate_processor_id(pr->acpi_id)) {
281 if (pr->acpi_id == 0xff)
282 dev_info_once(&device->dev,
283 "Entry not well-defined, consider updating BIOS\n");
284 else
285 dev_err(&device->dev,
286 "Failed to get unique processor _UID (0x%x)\n",
287 pr->acpi_id);
288 return -ENODEV;
289 }
290
291 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
292 pr->acpi_id);
293 if (invalid_phys_cpuid(pr->phys_id))
294 acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
295
296 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
297 if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
298 cpu0_initialized = 1;
299 /*
300 * Handle UP system running SMP kernel, with no CPU
301 * entry in MADT
302 */
303 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
304 pr->id = 0;
305 }
306
307 /*
308 * Extra Processor objects may be enumerated on MP systems with
309 * less than the max # of CPUs. They should be ignored _iff
310 * they are physically not present.
311 *
312 * NOTE: Even if the processor has a cpuid, it may not be present
313 * because cpuid <-> apicid mapping is persistent now.
314 */
315 if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
316 int ret = acpi_processor_hotadd_init(pr);
317 if (ret)
318 return ret;
319 }
320
321 /*
322 * On some boxes several processors use the same processor bus id.
323 * But they are located in different scope. For example:
324 * \_SB.SCK0.CPU0
325 * \_SB.SCK1.CPU0
326 * Rename the processor device bus id. And the new bus id will be
327 * generated as the following format:
328 * CPU+CPU ID.
329 */
330 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
331 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
332 pr->acpi_id));
333
334 if (!object.processor.pblk_address)
335 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
336 else if (object.processor.pblk_length != 6)
337 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
338 object.processor.pblk_length);
339 else {
340 pr->throttling.address = object.processor.pblk_address;
341 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
342 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
343
344 pr->pblk = object.processor.pblk_address;
345 }
346
347 /*
348 * If ACPI describes a slot number for this CPU, we can use it to
349 * ensure we get the right value in the "physical id" field
350 * of /proc/cpuinfo
351 */
352 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
353 if (ACPI_SUCCESS(status))
354 arch_fix_phys_package_id(pr->id, value);
355
356 return 0;
357 }
358
359 /*
360 * Do not put anything in here which needs the core to be online.
361 * For example MSR access or setting up things which check for cpuinfo_x86
362 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
363 * Such things have to be put in and set up by the processor driver's .probe().
364 */
365 static DEFINE_PER_CPU(void *, processor_device_array);
366
acpi_processor_add(struct acpi_device * device,const struct acpi_device_id * id)367 static int acpi_processor_add(struct acpi_device *device,
368 const struct acpi_device_id *id)
369 {
370 struct acpi_processor *pr;
371 struct device *dev;
372 int result = 0;
373
374 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
375 if (!pr)
376 return -ENOMEM;
377
378 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
379 result = -ENOMEM;
380 goto err_free_pr;
381 }
382
383 pr->handle = device->handle;
384 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
385 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
386 device->driver_data = pr;
387
388 result = acpi_processor_get_info(device);
389 if (result) /* Processor is not physically present or unavailable */
390 return 0;
391
392 BUG_ON(pr->id >= nr_cpu_ids);
393
394 /*
395 * Buggy BIOS check.
396 * ACPI id of processors can be reported wrongly by the BIOS.
397 * Don't trust it blindly
398 */
399 if (per_cpu(processor_device_array, pr->id) != NULL &&
400 per_cpu(processor_device_array, pr->id) != device) {
401 dev_warn(&device->dev,
402 "BIOS reported wrong ACPI id %d for the processor\n",
403 pr->id);
404 /* Give up, but do not abort the namespace scan. */
405 goto err;
406 }
407 /*
408 * processor_device_array is not cleared on errors to allow buggy BIOS
409 * checks.
410 */
411 per_cpu(processor_device_array, pr->id) = device;
412 per_cpu(processors, pr->id) = pr;
413
414 dev = get_cpu_device(pr->id);
415 if (!dev) {
416 result = -ENODEV;
417 goto err;
418 }
419
420 result = acpi_bind_one(dev, device);
421 if (result)
422 goto err;
423
424 pr->dev = dev;
425
426 /* Trigger the processor driver's .probe() if present. */
427 if (device_attach(dev) >= 0)
428 return 1;
429
430 dev_err(dev, "Processor driver could not be attached\n");
431 acpi_unbind_one(dev);
432
433 err:
434 free_cpumask_var(pr->throttling.shared_cpu_map);
435 device->driver_data = NULL;
436 per_cpu(processors, pr->id) = NULL;
437 err_free_pr:
438 kfree(pr);
439 return result;
440 }
441
442 #ifdef CONFIG_ACPI_HOTPLUG_CPU
443 /* --------------------------------------------------------------------------
444 Removal
445 -------------------------------------------------------------------------- */
446
acpi_processor_remove(struct acpi_device * device)447 static void acpi_processor_remove(struct acpi_device *device)
448 {
449 struct acpi_processor *pr;
450
451 if (!device || !acpi_driver_data(device))
452 return;
453
454 pr = acpi_driver_data(device);
455 if (pr->id >= nr_cpu_ids)
456 goto out;
457
458 /*
459 * The only reason why we ever get here is CPU hot-removal. The CPU is
460 * already offline and the ACPI device removal locking prevents it from
461 * being put back online at this point.
462 *
463 * Unbind the driver from the processor device and detach it from the
464 * ACPI companion object.
465 */
466 device_release_driver(pr->dev);
467 acpi_unbind_one(pr->dev);
468
469 /* Clean up. */
470 per_cpu(processor_device_array, pr->id) = NULL;
471 per_cpu(processors, pr->id) = NULL;
472
473 cpu_maps_update_begin();
474 cpu_hotplug_begin();
475
476 /* Remove the CPU. */
477 arch_unregister_cpu(pr->id);
478 acpi_unmap_cpu(pr->id);
479
480 cpu_hotplug_done();
481 cpu_maps_update_done();
482
483 try_offline_node(cpu_to_node(pr->id));
484
485 out:
486 free_cpumask_var(pr->throttling.shared_cpu_map);
487 kfree(pr);
488 }
489 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
490
491 #ifdef CONFIG_X86
492 static bool acpi_hwp_native_thermal_lvt_set;
acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,u32 lvl,void * context,void ** rv)493 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
494 u32 lvl,
495 void *context,
496 void **rv)
497 {
498 u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
499 u32 capbuf[2];
500 struct acpi_osc_context osc_context = {
501 .uuid_str = sb_uuid_str,
502 .rev = 1,
503 .cap.length = 8,
504 .cap.pointer = capbuf,
505 };
506
507 if (acpi_hwp_native_thermal_lvt_set)
508 return AE_CTRL_TERMINATE;
509
510 capbuf[0] = 0x0000;
511 capbuf[1] = 0x1000; /* set bit 12 */
512
513 if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
514 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
515 u32 *capbuf_ret = osc_context.ret.pointer;
516
517 if (capbuf_ret[1] & 0x1000) {
518 acpi_handle_info(handle,
519 "_OSC native thermal LVT Acked\n");
520 acpi_hwp_native_thermal_lvt_set = true;
521 }
522 }
523 kfree(osc_context.ret.pointer);
524 }
525
526 return AE_OK;
527 }
528
acpi_early_processor_osc(void)529 void __init acpi_early_processor_osc(void)
530 {
531 if (boot_cpu_has(X86_FEATURE_HWP)) {
532 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
533 ACPI_UINT32_MAX,
534 acpi_hwp_native_thermal_lvt_osc,
535 NULL, NULL, NULL);
536 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
537 acpi_hwp_native_thermal_lvt_osc,
538 NULL, NULL);
539 }
540 }
541 #endif
542
543 /*
544 * The following ACPI IDs are known to be suitable for representing as
545 * processor devices.
546 */
547 static const struct acpi_device_id processor_device_ids[] = {
548
549 { ACPI_PROCESSOR_OBJECT_HID, },
550 { ACPI_PROCESSOR_DEVICE_HID, },
551
552 { }
553 };
554
555 static struct acpi_scan_handler processor_handler = {
556 .ids = processor_device_ids,
557 .attach = acpi_processor_add,
558 #ifdef CONFIG_ACPI_HOTPLUG_CPU
559 .detach = acpi_processor_remove,
560 #endif
561 .hotplug = {
562 .enabled = true,
563 },
564 };
565
acpi_processor_container_attach(struct acpi_device * dev,const struct acpi_device_id * id)566 static int acpi_processor_container_attach(struct acpi_device *dev,
567 const struct acpi_device_id *id)
568 {
569 return 1;
570 }
571
572 static const struct acpi_device_id processor_container_ids[] = {
573 { ACPI_PROCESSOR_CONTAINER_HID, },
574 { }
575 };
576
577 static struct acpi_scan_handler processor_container_handler = {
578 .ids = processor_container_ids,
579 .attach = acpi_processor_container_attach,
580 };
581
582 /* The number of the unique processor IDs */
583 static int nr_unique_ids __initdata;
584
585 /* The number of the duplicate processor IDs */
586 static int nr_duplicate_ids;
587
588 /* Used to store the unique processor IDs */
589 static int unique_processor_ids[] __initdata = {
590 [0 ... NR_CPUS - 1] = -1,
591 };
592
593 /* Used to store the duplicate processor IDs */
594 static int duplicate_processor_ids[] = {
595 [0 ... NR_CPUS - 1] = -1,
596 };
597
processor_validated_ids_update(int proc_id)598 static void __init processor_validated_ids_update(int proc_id)
599 {
600 int i;
601
602 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
603 return;
604
605 /*
606 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
607 * already in the IDs, do nothing.
608 */
609 for (i = 0; i < nr_duplicate_ids; i++) {
610 if (duplicate_processor_ids[i] == proc_id)
611 return;
612 }
613
614 /*
615 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
616 * the IDs, put it in the duplicate IDs.
617 */
618 for (i = 0; i < nr_unique_ids; i++) {
619 if (unique_processor_ids[i] == proc_id) {
620 duplicate_processor_ids[nr_duplicate_ids] = proc_id;
621 nr_duplicate_ids++;
622 return;
623 }
624 }
625
626 /*
627 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
628 */
629 unique_processor_ids[nr_unique_ids] = proc_id;
630 nr_unique_ids++;
631 }
632
acpi_processor_ids_walk(acpi_handle handle,u32 lvl,void * context,void ** rv)633 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
634 u32 lvl,
635 void *context,
636 void **rv)
637 {
638 acpi_status status;
639 acpi_object_type acpi_type;
640 unsigned long long uid;
641 union acpi_object object = { 0 };
642 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
643
644 status = acpi_get_type(handle, &acpi_type);
645 if (ACPI_FAILURE(status))
646 return status;
647
648 switch (acpi_type) {
649 case ACPI_TYPE_PROCESSOR:
650 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
651 if (ACPI_FAILURE(status))
652 goto err;
653 uid = object.processor.proc_id;
654 break;
655
656 case ACPI_TYPE_DEVICE:
657 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
658 if (ACPI_FAILURE(status))
659 goto err;
660 break;
661 default:
662 goto err;
663 }
664
665 processor_validated_ids_update(uid);
666 return AE_OK;
667
668 err:
669 /* Exit on error, but don't abort the namespace walk */
670 acpi_handle_info(handle, "Invalid processor object\n");
671 return AE_OK;
672
673 }
674
acpi_processor_check_duplicates(void)675 static void __init acpi_processor_check_duplicates(void)
676 {
677 /* check the correctness for all processors in ACPI namespace */
678 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
679 ACPI_UINT32_MAX,
680 acpi_processor_ids_walk,
681 NULL, NULL, NULL);
682 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
683 NULL, NULL);
684 }
685
acpi_duplicate_processor_id(int proc_id)686 bool acpi_duplicate_processor_id(int proc_id)
687 {
688 int i;
689
690 /*
691 * compare the proc_id with duplicate IDs, if the proc_id is already
692 * in the duplicate IDs, return true, otherwise, return false.
693 */
694 for (i = 0; i < nr_duplicate_ids; i++) {
695 if (duplicate_processor_ids[i] == proc_id)
696 return true;
697 }
698 return false;
699 }
700
acpi_processor_init(void)701 void __init acpi_processor_init(void)
702 {
703 acpi_processor_check_duplicates();
704 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
705 acpi_scan_add_handler(&processor_container_handler);
706 }
707
708 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
709 /**
710 * acpi_processor_claim_cst_control - Request _CST control from the platform.
711 */
acpi_processor_claim_cst_control(void)712 bool acpi_processor_claim_cst_control(void)
713 {
714 static bool cst_control_claimed;
715 acpi_status status;
716
717 if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
718 return true;
719
720 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
721 acpi_gbl_FADT.cst_control, 8);
722 if (ACPI_FAILURE(status)) {
723 pr_warn("ACPI: Failed to claim processor _CST control\n");
724 return false;
725 }
726
727 cst_control_claimed = true;
728 return true;
729 }
730 EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
731
732 /**
733 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
734 * @handle: ACPI handle of the processor object containing the _CST.
735 * @cpu: The numeric ID of the target CPU.
736 * @info: Object write the C-states information into.
737 *
738 * Extract the C-state information for the given CPU from the output of the _CST
739 * control method under the corresponding ACPI processor object (or processor
740 * device object) and populate @info with it.
741 *
742 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
743 * acpi_processor_ffh_cstate_probe() to verify them and update the
744 * cpu_cstate_entry data for @cpu.
745 */
acpi_processor_evaluate_cst(acpi_handle handle,u32 cpu,struct acpi_processor_power * info)746 int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
747 struct acpi_processor_power *info)
748 {
749 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
750 union acpi_object *cst;
751 acpi_status status;
752 u64 count;
753 int last_index = 0;
754 int i, ret = 0;
755
756 status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
757 if (ACPI_FAILURE(status)) {
758 acpi_handle_debug(handle, "No _CST\n");
759 return -ENODEV;
760 }
761
762 cst = buffer.pointer;
763
764 /* There must be at least 2 elements. */
765 if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
766 acpi_handle_warn(handle, "Invalid _CST output\n");
767 ret = -EFAULT;
768 goto end;
769 }
770
771 count = cst->package.elements[0].integer.value;
772
773 /* Validate the number of C-states. */
774 if (count < 1 || count != cst->package.count - 1) {
775 acpi_handle_warn(handle, "Inconsistent _CST data\n");
776 ret = -EFAULT;
777 goto end;
778 }
779
780 for (i = 1; i <= count; i++) {
781 union acpi_object *element;
782 union acpi_object *obj;
783 struct acpi_power_register *reg;
784 struct acpi_processor_cx cx;
785
786 /*
787 * If there is not enough space for all C-states, skip the
788 * excess ones and log a warning.
789 */
790 if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
791 acpi_handle_warn(handle,
792 "No room for more idle states (limit: %d)\n",
793 ACPI_PROCESSOR_MAX_POWER - 1);
794 break;
795 }
796
797 memset(&cx, 0, sizeof(cx));
798
799 element = &cst->package.elements[i];
800 if (element->type != ACPI_TYPE_PACKAGE) {
801 acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
802 i, element->type);
803 continue;
804 }
805
806 if (element->package.count != 4) {
807 acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
808 i, element->package.count);
809 continue;
810 }
811
812 obj = &element->package.elements[0];
813
814 if (obj->type != ACPI_TYPE_BUFFER) {
815 acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
816 i, obj->type);
817 continue;
818 }
819
820 reg = (struct acpi_power_register *)obj->buffer.pointer;
821
822 obj = &element->package.elements[1];
823 if (obj->type != ACPI_TYPE_INTEGER) {
824 acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
825 i, obj->type);
826 continue;
827 }
828
829 cx.type = obj->integer.value;
830 /*
831 * There are known cases in which the _CST output does not
832 * contain C1, so if the type of the first state found is not
833 * C1, leave an empty slot for C1 to be filled in later.
834 */
835 if (i == 1 && cx.type != ACPI_STATE_C1)
836 last_index = 1;
837
838 cx.address = reg->address;
839 cx.index = last_index + 1;
840
841 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
842 if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
843 /*
844 * In the majority of cases _CST describes C1 as
845 * a FIXED_HARDWARE C-state, but if the command
846 * line forbids using MWAIT, use CSTATE_HALT for
847 * C1 regardless.
848 */
849 if (cx.type == ACPI_STATE_C1 &&
850 boot_option_idle_override == IDLE_NOMWAIT) {
851 cx.entry_method = ACPI_CSTATE_HALT;
852 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
853 } else {
854 cx.entry_method = ACPI_CSTATE_FFH;
855 }
856 } else if (cx.type == ACPI_STATE_C1) {
857 /*
858 * In the special case of C1, FIXED_HARDWARE can
859 * be handled by executing the HLT instruction.
860 */
861 cx.entry_method = ACPI_CSTATE_HALT;
862 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
863 } else {
864 acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
865 i);
866 continue;
867 }
868 } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
869 cx.entry_method = ACPI_CSTATE_SYSTEMIO;
870 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
871 cx.address);
872 } else {
873 acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
874 i, reg->space_id);
875 continue;
876 }
877
878 if (cx.type == ACPI_STATE_C1)
879 cx.valid = 1;
880
881 obj = &element->package.elements[2];
882 if (obj->type != ACPI_TYPE_INTEGER) {
883 acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
884 i, obj->type);
885 continue;
886 }
887
888 cx.latency = obj->integer.value;
889
890 obj = &element->package.elements[3];
891 if (obj->type != ACPI_TYPE_INTEGER) {
892 acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
893 i, obj->type);
894 continue;
895 }
896
897 memcpy(&info->states[++last_index], &cx, sizeof(cx));
898 }
899
900 acpi_handle_info(handle, "Found %d idle states\n", last_index);
901
902 info->count = last_index;
903
904 end:
905 kfree(buffer.pointer);
906
907 return ret;
908 }
909 EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
910 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */
911