1/*
2 * acpi_processor.c - ACPI processor enumeration support
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * Copyright (C) 2013, Intel Corporation
9 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License version 2 as published
13 * by the Free Software Foundation.
14 */
15
16#include <linux/acpi.h>
17#include <linux/device.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/pci.h>
21
22#include <acpi/processor.h>
23
24#include <asm/cpu.h>
25
26#include "internal.h"
27
28#define _COMPONENT ACPI_PROCESSOR_COMPONENT
29
30ACPI_MODULE_NAME("processor");
31
32DEFINE_PER_CPU(struct acpi_processor *, processors);
33EXPORT_PER_CPU_SYMBOL(processors);
34
35/* --------------------------------------------------------------------------
36 Errata Handling
37 -------------------------------------------------------------------------- */
38
39struct acpi_processor_errata errata __read_mostly;
40EXPORT_SYMBOL_GPL(errata);
41
42static int acpi_processor_errata_piix4(struct pci_dev *dev)
43{
44 u8 value1 = 0;
45 u8 value2 = 0;
46
47
48 if (!dev)
49 return -EINVAL;
50
51 /*
52 * Note that 'dev' references the PIIX4 ACPI Controller.
53 */
54
55 switch (dev->revision) {
56 case 0:
57 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
58 break;
59 case 1:
60 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
61 break;
62 case 2:
63 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
64 break;
65 case 3:
66 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
67 break;
68 default:
69 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
70 break;
71 }
72
73 switch (dev->revision) {
74
75 case 0: /* PIIX4 A-step */
76 case 1: /* PIIX4 B-step */
77 /*
78 * See specification changes #13 ("Manual Throttle Duty Cycle")
79 * and #14 ("Enabling and Disabling Manual Throttle"), plus
80 * erratum #5 ("STPCLK# Deassertion Time") from the January
81 * 2002 PIIX4 specification update. Applies to only older
82 * PIIX4 models.
83 */
84 errata.piix4.throttle = 1;
85 /* fall through*/
86
87 case 2: /* PIIX4E */
88 case 3: /* PIIX4M */
89 /*
90 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
91 * Livelock") from the January 2002 PIIX4 specification update.
92 * Applies to all PIIX4 models.
93 */
94
95 /*
96 * BM-IDE
97 * ------
98 * Find the PIIX4 IDE Controller and get the Bus Master IDE
99 * Status register address. We'll use this later to read
100 * each IDE controller's DMA status to make sure we catch all
101 * DMA activity.
102 */
103 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
104 PCI_DEVICE_ID_INTEL_82371AB,
105 PCI_ANY_ID, PCI_ANY_ID, NULL);
106 if (dev) {
107 errata.piix4.bmisx = pci_resource_start(dev, 4);
108 pci_dev_put(dev);
109 }
110
111 /*
112 * Type-F DMA
113 * ----------
114 * Find the PIIX4 ISA Controller and read the Motherboard
115 * DMA controller's status to see if Type-F (Fast) DMA mode
116 * is enabled (bit 7) on either channel. Note that we'll
117 * disable C3 support if this is enabled, as some legacy
118 * devices won't operate well if fast DMA is disabled.
119 */
120 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
121 PCI_DEVICE_ID_INTEL_82371AB_0,
122 PCI_ANY_ID, PCI_ANY_ID, NULL);
123 if (dev) {
124 pci_read_config_byte(dev, 0x76, &value1);
125 pci_read_config_byte(dev, 0x77, &value2);
126 if ((value1 & 0x80) || (value2 & 0x80))
127 errata.piix4.fdma = 1;
128 pci_dev_put(dev);
129 }
130
131 break;
132 }
133
134 if (errata.piix4.bmisx)
135 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
136 "Bus master activity detection (BM-IDE) erratum enabled\n"));
137 if (errata.piix4.fdma)
138 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
139 "Type-F DMA livelock erratum (C3 disabled)\n"));
140
141 return 0;
142}
143
144static int acpi_processor_errata(void)
145{
146 int result = 0;
147 struct pci_dev *dev = NULL;
148
149 /*
150 * PIIX4
151 */
152 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
153 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
154 PCI_ANY_ID, NULL);
155 if (dev) {
156 result = acpi_processor_errata_piix4(dev);
157 pci_dev_put(dev);
158 }
159
160 return result;
161}
162
163/* --------------------------------------------------------------------------
164 Initialization
165 -------------------------------------------------------------------------- */
166
167#ifdef CONFIG_ACPI_HOTPLUG_CPU
168int __weak acpi_map_cpu(acpi_handle handle,
169 phys_cpuid_t physid, u32 acpi_id, int *pcpu)
170{
171 return -ENODEV;
172}
173
174int __weak acpi_unmap_cpu(int cpu)
175{
176 return -ENODEV;
177}
178
179int __weak arch_register_cpu(int cpu)
180{
181 return -ENODEV;
182}
183
184void __weak arch_unregister_cpu(int cpu) {}
185
186static int acpi_processor_hotadd_init(struct acpi_processor *pr)
187{
188 unsigned long long sta;
189 acpi_status status;
190 int ret;
191
192 if (invalid_phys_cpuid(pr->phys_id))
193 return -ENODEV;
194
195 status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
196 if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
197 return -ENODEV;
198
199 cpu_maps_update_begin();
200 cpu_hotplug_begin();
201
202 ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
203 if (ret)
204 goto out;
205
206 ret = arch_register_cpu(pr->id);
207 if (ret) {
208 acpi_unmap_cpu(pr->id);
209 goto out;
210 }
211
212 /*
213 * CPU got hot-added, but cpu_data is not initialized yet. Set a flag
214 * to delay cpu_idle/throttling initialization and do it when the CPU
215 * gets online for the first time.
216 */
217 pr_info("CPU%d has been hot-added\n", pr->id);
218 pr->flags.need_hotplug_init = 1;
219
220out:
221 cpu_hotplug_done();
222 cpu_maps_update_done();
223 return ret;
224}
225#else
226static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
227{
228 return -ENODEV;
229}
230#endif /* CONFIG_ACPI_HOTPLUG_CPU */
231
232static int acpi_processor_get_info(struct acpi_device *device)
233{
234 union acpi_object object = { 0 };
235 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
236 struct acpi_processor *pr = acpi_driver_data(device);
237 int device_declaration = 0;
238 acpi_status status = AE_OK;
239 static int cpu0_initialized;
240 unsigned long long value;
241
242 acpi_processor_errata();
243
244 /*
245 * Check to see if we have bus mastering arbitration control. This
246 * is required for proper C3 usage (to maintain cache coherency).
247 */
248 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
249 pr->flags.bm_control = 1;
250 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
251 "Bus mastering arbitration control present\n"));
252 } else
253 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
254 "No bus mastering arbitration control\n"));
255
256 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
257 /* Declared with "Processor" statement; match ProcessorID */
258 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
259 if (ACPI_FAILURE(status)) {
260 dev_err(&device->dev,
261 "Failed to evaluate processor object (0x%x)\n",
262 status);
263 return -ENODEV;
264 }
265
266 pr->acpi_id = object.processor.proc_id;
267 } else {
268 /*
269 * Declared with "Device" statement; match _UID.
270 * Note that we don't handle string _UIDs yet.
271 */
272 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
273 NULL, &value);
274 if (ACPI_FAILURE(status)) {
275 dev_err(&device->dev,
276 "Failed to evaluate processor _UID (0x%x)\n",
277 status);
278 return -ENODEV;
279 }
280 device_declaration = 1;
281 pr->acpi_id = value;
282 }
283
284 if (acpi_duplicate_processor_id(pr->acpi_id)) {
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 */
365static DEFINE_PER_CPU(void *, processor_device_array);
366
367static 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
447static 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
492static bool acpi_hwp_native_thermal_lvt_set;
493static 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
529void __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 */
547static const struct acpi_device_id processor_device_ids[] = {
548
549 { ACPI_PROCESSOR_OBJECT_HID, },
550 { ACPI_PROCESSOR_DEVICE_HID, },
551
552 { }
553};
554
555static 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
566static int acpi_processor_container_attach(struct acpi_device *dev,
567 const struct acpi_device_id *id)
568{
569 return 1;
570}
571
572static const struct acpi_device_id processor_container_ids[] = {
573 { ACPI_PROCESSOR_CONTAINER_HID, },
574 { }
575};
576
577static 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 */
583static int nr_unique_ids __initdata;
584
585/* The number of the duplicate processor IDs */
586static int nr_duplicate_ids;
587
588/* Used to store the unique processor IDs */
589static int unique_processor_ids[] __initdata = {
590 [0 ... NR_CPUS - 1] = -1,
591};
592
593/* Used to store the duplicate processor IDs */
594static int duplicate_processor_ids[] = {
595 [0 ... NR_CPUS - 1] = -1,
596};
597
598static 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
633static 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
668err:
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
675static 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
686bool 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
701void __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