2 * acpi_processor.c - ACPI processor enumeration support
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>
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.
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>
22 #include <acpi/processor.h>
28 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
30 ACPI_MODULE_NAME("processor");
32 DEFINE_PER_CPU(struct acpi_processor *, processors);
33 EXPORT_PER_CPU_SYMBOL(processors);
35 /* --------------------------------------------------------------------------
37 -------------------------------------------------------------------------- */
39 struct acpi_processor_errata errata __read_mostly;
40 EXPORT_SYMBOL_GPL(errata);
42 static int acpi_processor_errata_piix4(struct pci_dev *dev)
52 * Note that 'dev' references the PIIX4 ACPI Controller.
55 switch (dev->revision) {
57 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
60 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
63 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
66 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
69 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
73 switch (dev->revision) {
75 case 0: /* PIIX4 A-step */
76 case 1: /* PIIX4 B-step */
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
84 errata.piix4.throttle = 1;
89 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
90 * Livelock") from the January 2002 PIIX4 specification update.
91 * Applies to all PIIX4 models.
97 * Find the PIIX4 IDE Controller and get the Bus Master IDE
98 * Status register address. We'll use this later to read
99 * each IDE controller's DMA status to make sure we catch all
102 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
103 PCI_DEVICE_ID_INTEL_82371AB,
104 PCI_ANY_ID, PCI_ANY_ID, NULL);
106 errata.piix4.bmisx = pci_resource_start(dev, 4);
113 * Find the PIIX4 ISA Controller and read the Motherboard
114 * DMA controller's status to see if Type-F (Fast) DMA mode
115 * is enabled (bit 7) on either channel. Note that we'll
116 * disable C3 support if this is enabled, as some legacy
117 * devices won't operate well if fast DMA is disabled.
119 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
120 PCI_DEVICE_ID_INTEL_82371AB_0,
121 PCI_ANY_ID, PCI_ANY_ID, NULL);
123 pci_read_config_byte(dev, 0x76, &value1);
124 pci_read_config_byte(dev, 0x77, &value2);
125 if ((value1 & 0x80) || (value2 & 0x80))
126 errata.piix4.fdma = 1;
133 if (errata.piix4.bmisx)
134 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
135 "Bus master activity detection (BM-IDE) erratum enabled\n"));
136 if (errata.piix4.fdma)
137 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
138 "Type-F DMA livelock erratum (C3 disabled)\n"));
143 static int acpi_processor_errata(void)
146 struct pci_dev *dev = NULL;
151 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
152 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
155 result = acpi_processor_errata_piix4(dev);
162 /* --------------------------------------------------------------------------
164 -------------------------------------------------------------------------- */
166 #ifdef CONFIG_ACPI_HOTPLUG_CPU
167 int __weak acpi_map_cpu(acpi_handle handle,
168 phys_cpuid_t physid, u32 acpi_id, int *pcpu)
173 int __weak acpi_unmap_cpu(int cpu)
178 int __weak arch_register_cpu(int cpu)
183 void __weak arch_unregister_cpu(int cpu) {}
185 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
187 unsigned long long sta;
191 if (invalid_phys_cpuid(pr->phys_id))
194 status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
195 if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
198 cpu_maps_update_begin();
201 ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
205 ret = arch_register_cpu(pr->id);
207 acpi_unmap_cpu(pr->id);
212 * CPU got hot-added, but cpu_data is not initialized yet. Set a flag
213 * to delay cpu_idle/throttling initialization and do it when the CPU
214 * gets online for the first time.
216 pr_info("CPU%d has been hot-added\n", pr->id);
217 pr->flags.need_hotplug_init = 1;
221 cpu_maps_update_done();
225 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
229 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
231 static int acpi_processor_get_info(struct acpi_device *device)
233 union acpi_object object = { 0 };
234 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
235 struct acpi_processor *pr = acpi_driver_data(device);
236 int device_declaration = 0;
237 acpi_status status = AE_OK;
238 static int cpu0_initialized;
239 unsigned long long value;
241 acpi_processor_errata();
244 * Check to see if we have bus mastering arbitration control. This
245 * is required for proper C3 usage (to maintain cache coherency).
247 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
248 pr->flags.bm_control = 1;
249 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
250 "Bus mastering arbitration control present\n"));
252 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
253 "No bus mastering arbitration control\n"));
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",
265 pr->acpi_id = object.processor.proc_id;
268 * Declared with "Device" statement; match _UID.
269 * Note that we don't handle string _UIDs yet.
271 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
273 if (ACPI_FAILURE(status)) {
274 dev_err(&device->dev,
275 "Failed to evaluate processor _UID (0x%x)\n",
279 device_declaration = 1;
283 if (acpi_duplicate_processor_id(pr->acpi_id)) {
284 dev_err(&device->dev,
285 "Failed to get unique processor _UID (0x%x)\n",
290 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
292 if (invalid_phys_cpuid(pr->phys_id))
293 acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
295 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
296 if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
297 cpu0_initialized = 1;
299 * Handle UP system running SMP kernel, with no CPU
302 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
307 * Extra Processor objects may be enumerated on MP systems with
308 * less than the max # of CPUs. They should be ignored _iff
309 * they are physically not present.
311 * NOTE: Even if the processor has a cpuid, it may not be present
312 * because cpuid <-> apicid mapping is persistent now.
314 if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
315 int ret = acpi_processor_hotadd_init(pr);
321 * On some boxes several processors use the same processor bus id.
322 * But they are located in different scope. For example:
325 * Rename the processor device bus id. And the new bus id will be
326 * generated as the following format:
329 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
330 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
333 if (!object.processor.pblk_address)
334 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
335 else if (object.processor.pblk_length != 6)
336 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
337 object.processor.pblk_length);
339 pr->throttling.address = object.processor.pblk_address;
340 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
341 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
343 pr->pblk = object.processor.pblk_address;
347 * If ACPI describes a slot number for this CPU, we can use it to
348 * ensure we get the right value in the "physical id" field
351 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
352 if (ACPI_SUCCESS(status))
353 arch_fix_phys_package_id(pr->id, value);
359 * Do not put anything in here which needs the core to be online.
360 * For example MSR access or setting up things which check for cpuinfo_x86
361 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
362 * Such things have to be put in and set up by the processor driver's .probe().
364 static DEFINE_PER_CPU(void *, processor_device_array);
366 static int acpi_processor_add(struct acpi_device *device,
367 const struct acpi_device_id *id)
369 struct acpi_processor *pr;
373 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
377 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
382 pr->handle = device->handle;
383 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
384 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
385 device->driver_data = pr;
387 result = acpi_processor_get_info(device);
388 if (result) /* Processor is not physically present or unavailable */
391 BUG_ON(pr->id >= nr_cpu_ids);
395 * ACPI id of processors can be reported wrongly by the BIOS.
396 * Don't trust it blindly
398 if (per_cpu(processor_device_array, pr->id) != NULL &&
399 per_cpu(processor_device_array, pr->id) != device) {
400 dev_warn(&device->dev,
401 "BIOS reported wrong ACPI id %d for the processor\n",
403 /* Give up, but do not abort the namespace scan. */
407 * processor_device_array is not cleared on errors to allow buggy BIOS
410 per_cpu(processor_device_array, pr->id) = device;
411 per_cpu(processors, pr->id) = pr;
413 dev = get_cpu_device(pr->id);
419 result = acpi_bind_one(dev, device);
425 /* Trigger the processor driver's .probe() if present. */
426 if (device_attach(dev) >= 0)
429 dev_err(dev, "Processor driver could not be attached\n");
430 acpi_unbind_one(dev);
433 free_cpumask_var(pr->throttling.shared_cpu_map);
434 device->driver_data = NULL;
435 per_cpu(processors, pr->id) = NULL;
441 #ifdef CONFIG_ACPI_HOTPLUG_CPU
442 /* --------------------------------------------------------------------------
444 -------------------------------------------------------------------------- */
446 static void acpi_processor_remove(struct acpi_device *device)
448 struct acpi_processor *pr;
450 if (!device || !acpi_driver_data(device))
453 pr = acpi_driver_data(device);
454 if (pr->id >= nr_cpu_ids)
458 * The only reason why we ever get here is CPU hot-removal. The CPU is
459 * already offline and the ACPI device removal locking prevents it from
460 * being put back online at this point.
462 * Unbind the driver from the processor device and detach it from the
463 * ACPI companion object.
465 device_release_driver(pr->dev);
466 acpi_unbind_one(pr->dev);
469 per_cpu(processor_device_array, pr->id) = NULL;
470 per_cpu(processors, pr->id) = NULL;
472 cpu_maps_update_begin();
475 /* Remove the CPU. */
476 arch_unregister_cpu(pr->id);
477 acpi_unmap_cpu(pr->id);
480 cpu_maps_update_done();
482 try_offline_node(cpu_to_node(pr->id));
485 free_cpumask_var(pr->throttling.shared_cpu_map);
488 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
491 static bool acpi_hwp_native_thermal_lvt_set;
492 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
497 u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
499 struct acpi_osc_context osc_context = {
500 .uuid_str = sb_uuid_str,
503 .cap.pointer = capbuf,
506 if (acpi_hwp_native_thermal_lvt_set)
507 return AE_CTRL_TERMINATE;
510 capbuf[1] = 0x1000; /* set bit 12 */
512 if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
513 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
514 u32 *capbuf_ret = osc_context.ret.pointer;
516 if (capbuf_ret[1] & 0x1000) {
517 acpi_handle_info(handle,
518 "_OSC native thermal LVT Acked\n");
519 acpi_hwp_native_thermal_lvt_set = true;
522 kfree(osc_context.ret.pointer);
528 void __init acpi_early_processor_osc(void)
530 if (boot_cpu_has(X86_FEATURE_HWP)) {
531 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
533 acpi_hwp_native_thermal_lvt_osc,
535 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
536 acpi_hwp_native_thermal_lvt_osc,
543 * The following ACPI IDs are known to be suitable for representing as
546 static const struct acpi_device_id processor_device_ids[] = {
548 { ACPI_PROCESSOR_OBJECT_HID, },
549 { ACPI_PROCESSOR_DEVICE_HID, },
554 static struct acpi_scan_handler processor_handler = {
555 .ids = processor_device_ids,
556 .attach = acpi_processor_add,
557 #ifdef CONFIG_ACPI_HOTPLUG_CPU
558 .detach = acpi_processor_remove,
565 static int acpi_processor_container_attach(struct acpi_device *dev,
566 const struct acpi_device_id *id)
571 static const struct acpi_device_id processor_container_ids[] = {
572 { ACPI_PROCESSOR_CONTAINER_HID, },
576 static struct acpi_scan_handler processor_container_handler = {
577 .ids = processor_container_ids,
578 .attach = acpi_processor_container_attach,
581 /* The number of the unique processor IDs */
582 static int nr_unique_ids __initdata;
584 /* The number of the duplicate processor IDs */
585 static int nr_duplicate_ids;
587 /* Used to store the unique processor IDs */
588 static int unique_processor_ids[] __initdata = {
589 [0 ... NR_CPUS - 1] = -1,
592 /* Used to store the duplicate processor IDs */
593 static int duplicate_processor_ids[] = {
594 [0 ... NR_CPUS - 1] = -1,
597 static void __init processor_validated_ids_update(int proc_id)
601 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
605 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
606 * already in the IDs, do nothing.
608 for (i = 0; i < nr_duplicate_ids; i++) {
609 if (duplicate_processor_ids[i] == proc_id)
614 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
615 * the IDs, put it in the duplicate IDs.
617 for (i = 0; i < nr_unique_ids; i++) {
618 if (unique_processor_ids[i] == proc_id) {
619 duplicate_processor_ids[nr_duplicate_ids] = proc_id;
626 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
628 unique_processor_ids[nr_unique_ids] = proc_id;
632 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
638 acpi_object_type acpi_type;
639 unsigned long long uid;
640 union acpi_object object = { 0 };
641 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
643 status = acpi_get_type(handle, &acpi_type);
644 if (ACPI_FAILURE(status))
648 case ACPI_TYPE_PROCESSOR:
649 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
650 if (ACPI_FAILURE(status))
652 uid = object.processor.proc_id;
655 case ACPI_TYPE_DEVICE:
656 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
657 if (ACPI_FAILURE(status))
664 processor_validated_ids_update(uid);
668 acpi_handle_info(handle, "Invalid processor object\n");
673 static void __init acpi_processor_check_duplicates(void)
675 /* check the correctness for all processors in ACPI namespace */
676 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
678 acpi_processor_ids_walk,
680 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
684 bool acpi_duplicate_processor_id(int proc_id)
689 * compare the proc_id with duplicate IDs, if the proc_id is already
690 * in the duplicate IDs, return true, otherwise, return false.
692 for (i = 0; i < nr_duplicate_ids; i++) {
693 if (duplicate_processor_ids[i] == proc_id)
699 void __init acpi_processor_init(void)
701 acpi_processor_check_duplicates();
702 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
703 acpi_scan_add_handler(&processor_container_handler);