1 // SPDX-License-Identifier: GPL-2.0-only
3 * acpi_processor.c - ACPI processor enumeration support
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>
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>
19 #include <acpi/processor.h>
25 DEFINE_PER_CPU(struct acpi_processor *, processors);
26 EXPORT_PER_CPU_SYMBOL(processors);
29 struct acpi_processor_errata errata __read_mostly;
30 EXPORT_SYMBOL_GPL(errata);
32 static int acpi_processor_errata_piix4(struct pci_dev *dev)
42 * Note that 'dev' references the PIIX4 ACPI Controller.
45 switch (dev->revision) {
47 dev_dbg(&dev->dev, "Found PIIX4 A-step\n");
50 dev_dbg(&dev->dev, "Found PIIX4 B-step\n");
53 dev_dbg(&dev->dev, "Found PIIX4E\n");
56 dev_dbg(&dev->dev, "Found PIIX4M\n");
59 dev_dbg(&dev->dev, "Found unknown PIIX4\n");
63 switch (dev->revision) {
65 case 0: /* PIIX4 A-step */
66 case 1: /* PIIX4 B-step */
68 * See specification changes #13 ("Manual Throttle Duty Cycle")
69 * and #14 ("Enabling and Disabling Manual Throttle"), plus
70 * erratum #5 ("STPCLK# Deassertion Time") from the January
71 * 2002 PIIX4 specification update. Applies to only older
74 errata.piix4.throttle = 1;
80 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
81 * Livelock") from the January 2002 PIIX4 specification update.
82 * Applies to all PIIX4 models.
88 * Find the PIIX4 IDE Controller and get the Bus Master IDE
89 * Status register address. We'll use this later to read
90 * each IDE controller's DMA status to make sure we catch all
93 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
94 PCI_DEVICE_ID_INTEL_82371AB,
95 PCI_ANY_ID, PCI_ANY_ID, NULL);
97 errata.piix4.bmisx = pci_resource_start(dev, 4);
104 * Find the PIIX4 ISA Controller and read the Motherboard
105 * DMA controller's status to see if Type-F (Fast) DMA mode
106 * is enabled (bit 7) on either channel. Note that we'll
107 * disable C3 support if this is enabled, as some legacy
108 * devices won't operate well if fast DMA is disabled.
110 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
111 PCI_DEVICE_ID_INTEL_82371AB_0,
112 PCI_ANY_ID, PCI_ANY_ID, NULL);
114 pci_read_config_byte(dev, 0x76, &value1);
115 pci_read_config_byte(dev, 0x77, &value2);
116 if ((value1 & 0x80) || (value2 & 0x80))
117 errata.piix4.fdma = 1;
124 if (errata.piix4.bmisx)
125 dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");
126 if (errata.piix4.fdma)
127 dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");
132 static int acpi_processor_errata(void)
135 struct pci_dev *dev = NULL;
140 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
141 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
144 result = acpi_processor_errata_piix4(dev);
152 #ifdef CONFIG_ACPI_HOTPLUG_CPU
153 int __weak acpi_map_cpu(acpi_handle handle,
154 phys_cpuid_t physid, u32 acpi_id, int *pcpu)
159 int __weak acpi_unmap_cpu(int cpu)
164 int __weak arch_register_cpu(int cpu)
169 void __weak arch_unregister_cpu(int cpu) {}
171 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
173 unsigned long long sta;
177 if (invalid_phys_cpuid(pr->phys_id))
180 status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
181 if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
184 cpu_maps_update_begin();
187 ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
191 ret = arch_register_cpu(pr->id);
193 acpi_unmap_cpu(pr->id);
198 * CPU got hot-added, but cpu_data is not initialized yet. Set a flag
199 * to delay cpu_idle/throttling initialization and do it when the CPU
200 * gets online for the first time.
202 pr_info("CPU%d has been hot-added\n", pr->id);
203 pr->flags.need_hotplug_init = 1;
207 cpu_maps_update_done();
211 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
215 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
217 static int acpi_processor_get_info(struct acpi_device *device)
219 union acpi_object object = { 0 };
220 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
221 struct acpi_processor *pr = acpi_driver_data(device);
222 int device_declaration = 0;
223 acpi_status status = AE_OK;
224 static int cpu0_initialized;
225 unsigned long long value;
227 acpi_processor_errata();
230 * Check to see if we have bus mastering arbitration control. This
231 * is required for proper C3 usage (to maintain cache coherency).
233 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
234 pr->flags.bm_control = 1;
235 dev_dbg(&device->dev, "Bus mastering arbitration control present\n");
237 dev_dbg(&device->dev, "No bus mastering arbitration control\n");
239 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
240 /* Declared with "Processor" statement; match ProcessorID */
241 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
242 if (ACPI_FAILURE(status)) {
243 dev_err(&device->dev,
244 "Failed to evaluate processor object (0x%x)\n",
249 pr->acpi_id = object.processor.proc_id;
252 * Declared with "Device" statement; match _UID.
254 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
256 if (ACPI_FAILURE(status)) {
257 dev_err(&device->dev,
258 "Failed to evaluate processor _UID (0x%x)\n",
262 device_declaration = 1;
266 if (acpi_duplicate_processor_id(pr->acpi_id)) {
267 if (pr->acpi_id == 0xff)
268 dev_info_once(&device->dev,
269 "Entry not well-defined, consider updating BIOS\n");
271 dev_err(&device->dev,
272 "Failed to get unique processor _UID (0x%x)\n",
277 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
279 if (invalid_phys_cpuid(pr->phys_id))
280 dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");
282 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
283 if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
284 cpu0_initialized = 1;
286 * Handle UP system running SMP kernel, with no CPU
289 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
294 * Extra Processor objects may be enumerated on MP systems with
295 * less than the max # of CPUs. They should be ignored _iff
296 * they are physically not present.
298 * NOTE: Even if the processor has a cpuid, it may not be present
299 * because cpuid <-> apicid mapping is persistent now.
301 if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
302 int ret = acpi_processor_hotadd_init(pr);
309 * On some boxes several processors use the same processor bus id.
310 * But they are located in different scope. For example:
313 * Rename the processor device bus id. And the new bus id will be
314 * generated as the following format:
317 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
318 dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);
320 if (!object.processor.pblk_address)
321 dev_dbg(&device->dev, "No PBLK (NULL address)\n");
322 else if (object.processor.pblk_length != 6)
323 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
324 object.processor.pblk_length);
326 pr->throttling.address = object.processor.pblk_address;
327 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
328 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
330 pr->pblk = object.processor.pblk_address;
334 * If ACPI describes a slot number for this CPU, we can use it to
335 * ensure we get the right value in the "physical id" field
338 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
339 if (ACPI_SUCCESS(status))
340 arch_fix_phys_package_id(pr->id, value);
346 * Do not put anything in here which needs the core to be online.
347 * For example MSR access or setting up things which check for cpuinfo_x86
348 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
349 * Such things have to be put in and set up by the processor driver's .probe().
351 static DEFINE_PER_CPU(void *, processor_device_array);
353 static int acpi_processor_add(struct acpi_device *device,
354 const struct acpi_device_id *id)
356 struct acpi_processor *pr;
360 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
364 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
369 pr->handle = device->handle;
370 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
371 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
372 device->driver_data = pr;
374 result = acpi_processor_get_info(device);
375 if (result) /* Processor is not physically present or unavailable */
378 BUG_ON(pr->id >= nr_cpu_ids);
382 * ACPI id of processors can be reported wrongly by the BIOS.
383 * Don't trust it blindly
385 if (per_cpu(processor_device_array, pr->id) != NULL &&
386 per_cpu(processor_device_array, pr->id) != device) {
387 dev_warn(&device->dev,
388 "BIOS reported wrong ACPI id %d for the processor\n",
390 /* Give up, but do not abort the namespace scan. */
394 * processor_device_array is not cleared on errors to allow buggy BIOS
397 per_cpu(processor_device_array, pr->id) = device;
398 per_cpu(processors, pr->id) = pr;
400 dev = get_cpu_device(pr->id);
406 result = acpi_bind_one(dev, device);
412 /* Trigger the processor driver's .probe() if present. */
413 if (device_attach(dev) >= 0)
416 dev_err(dev, "Processor driver could not be attached\n");
417 acpi_unbind_one(dev);
420 free_cpumask_var(pr->throttling.shared_cpu_map);
421 device->driver_data = NULL;
422 per_cpu(processors, pr->id) = NULL;
428 #ifdef CONFIG_ACPI_HOTPLUG_CPU
430 static void acpi_processor_remove(struct acpi_device *device)
432 struct acpi_processor *pr;
434 if (!device || !acpi_driver_data(device))
437 pr = acpi_driver_data(device);
438 if (pr->id >= nr_cpu_ids)
442 * The only reason why we ever get here is CPU hot-removal. The CPU is
443 * already offline and the ACPI device removal locking prevents it from
444 * being put back online at this point.
446 * Unbind the driver from the processor device and detach it from the
447 * ACPI companion object.
449 device_release_driver(pr->dev);
450 acpi_unbind_one(pr->dev);
453 per_cpu(processor_device_array, pr->id) = NULL;
454 per_cpu(processors, pr->id) = NULL;
456 cpu_maps_update_begin();
459 /* Remove the CPU. */
460 arch_unregister_cpu(pr->id);
461 acpi_unmap_cpu(pr->id);
464 cpu_maps_update_done();
466 try_offline_node(cpu_to_node(pr->id));
469 free_cpumask_var(pr->throttling.shared_cpu_map);
472 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
475 static bool acpi_hwp_native_thermal_lvt_set;
476 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
481 u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
483 struct acpi_osc_context osc_context = {
484 .uuid_str = sb_uuid_str,
487 .cap.pointer = capbuf,
490 if (acpi_hwp_native_thermal_lvt_set)
491 return AE_CTRL_TERMINATE;
494 capbuf[1] = 0x1000; /* set bit 12 */
496 if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
497 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
498 u32 *capbuf_ret = osc_context.ret.pointer;
500 if (capbuf_ret[1] & 0x1000) {
501 acpi_handle_info(handle,
502 "_OSC native thermal LVT Acked\n");
503 acpi_hwp_native_thermal_lvt_set = true;
506 kfree(osc_context.ret.pointer);
512 void __init acpi_early_processor_osc(void)
514 if (boot_cpu_has(X86_FEATURE_HWP)) {
515 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
517 acpi_hwp_native_thermal_lvt_osc,
519 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
520 acpi_hwp_native_thermal_lvt_osc,
527 * The following ACPI IDs are known to be suitable for representing as
530 static const struct acpi_device_id processor_device_ids[] = {
532 { ACPI_PROCESSOR_OBJECT_HID, },
533 { ACPI_PROCESSOR_DEVICE_HID, },
538 static struct acpi_scan_handler processor_handler = {
539 .ids = processor_device_ids,
540 .attach = acpi_processor_add,
541 #ifdef CONFIG_ACPI_HOTPLUG_CPU
542 .detach = acpi_processor_remove,
549 static int acpi_processor_container_attach(struct acpi_device *dev,
550 const struct acpi_device_id *id)
555 static const struct acpi_device_id processor_container_ids[] = {
556 { ACPI_PROCESSOR_CONTAINER_HID, },
560 static struct acpi_scan_handler processor_container_handler = {
561 .ids = processor_container_ids,
562 .attach = acpi_processor_container_attach,
565 /* The number of the unique processor IDs */
566 static int nr_unique_ids __initdata;
568 /* The number of the duplicate processor IDs */
569 static int nr_duplicate_ids;
571 /* Used to store the unique processor IDs */
572 static int unique_processor_ids[] __initdata = {
573 [0 ... NR_CPUS - 1] = -1,
576 /* Used to store the duplicate processor IDs */
577 static int duplicate_processor_ids[] = {
578 [0 ... NR_CPUS - 1] = -1,
581 static void __init processor_validated_ids_update(int proc_id)
585 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
589 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
590 * already in the IDs, do nothing.
592 for (i = 0; i < nr_duplicate_ids; i++) {
593 if (duplicate_processor_ids[i] == proc_id)
598 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
599 * the IDs, put it in the duplicate IDs.
601 for (i = 0; i < nr_unique_ids; i++) {
602 if (unique_processor_ids[i] == proc_id) {
603 duplicate_processor_ids[nr_duplicate_ids] = proc_id;
610 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
612 unique_processor_ids[nr_unique_ids] = proc_id;
616 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
622 acpi_object_type acpi_type;
623 unsigned long long uid;
624 union acpi_object object = { 0 };
625 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
627 status = acpi_get_type(handle, &acpi_type);
628 if (ACPI_FAILURE(status))
632 case ACPI_TYPE_PROCESSOR:
633 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
634 if (ACPI_FAILURE(status))
636 uid = object.processor.proc_id;
639 case ACPI_TYPE_DEVICE:
640 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
641 if (ACPI_FAILURE(status))
648 processor_validated_ids_update(uid);
652 /* Exit on error, but don't abort the namespace walk */
653 acpi_handle_info(handle, "Invalid processor object\n");
658 static void __init acpi_processor_check_duplicates(void)
660 /* check the correctness for all processors in ACPI namespace */
661 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
663 acpi_processor_ids_walk,
665 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
669 bool acpi_duplicate_processor_id(int proc_id)
674 * compare the proc_id with duplicate IDs, if the proc_id is already
675 * in the duplicate IDs, return true, otherwise, return false.
677 for (i = 0; i < nr_duplicate_ids; i++) {
678 if (duplicate_processor_ids[i] == proc_id)
684 void __init acpi_processor_init(void)
686 acpi_processor_check_duplicates();
687 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
688 acpi_scan_add_handler(&processor_container_handler);
691 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
693 * acpi_processor_claim_cst_control - Request _CST control from the platform.
695 bool acpi_processor_claim_cst_control(void)
697 static bool cst_control_claimed;
700 if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
703 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
704 acpi_gbl_FADT.cst_control, 8);
705 if (ACPI_FAILURE(status)) {
706 pr_warn("ACPI: Failed to claim processor _CST control\n");
710 cst_control_claimed = true;
713 EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
716 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
717 * @handle: ACPI handle of the processor object containing the _CST.
718 * @cpu: The numeric ID of the target CPU.
719 * @info: Object write the C-states information into.
721 * Extract the C-state information for the given CPU from the output of the _CST
722 * control method under the corresponding ACPI processor object (or processor
723 * device object) and populate @info with it.
725 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
726 * acpi_processor_ffh_cstate_probe() to verify them and update the
727 * cpu_cstate_entry data for @cpu.
729 int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
730 struct acpi_processor_power *info)
732 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
733 union acpi_object *cst;
739 status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
740 if (ACPI_FAILURE(status)) {
741 acpi_handle_debug(handle, "No _CST\n");
745 cst = buffer.pointer;
747 /* There must be at least 2 elements. */
748 if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
749 acpi_handle_warn(handle, "Invalid _CST output\n");
754 count = cst->package.elements[0].integer.value;
756 /* Validate the number of C-states. */
757 if (count < 1 || count != cst->package.count - 1) {
758 acpi_handle_warn(handle, "Inconsistent _CST data\n");
763 for (i = 1; i <= count; i++) {
764 union acpi_object *element;
765 union acpi_object *obj;
766 struct acpi_power_register *reg;
767 struct acpi_processor_cx cx;
770 * If there is not enough space for all C-states, skip the
771 * excess ones and log a warning.
773 if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
774 acpi_handle_warn(handle,
775 "No room for more idle states (limit: %d)\n",
776 ACPI_PROCESSOR_MAX_POWER - 1);
780 memset(&cx, 0, sizeof(cx));
782 element = &cst->package.elements[i];
783 if (element->type != ACPI_TYPE_PACKAGE) {
784 acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
789 if (element->package.count != 4) {
790 acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
791 i, element->package.count);
795 obj = &element->package.elements[0];
797 if (obj->type != ACPI_TYPE_BUFFER) {
798 acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
803 reg = (struct acpi_power_register *)obj->buffer.pointer;
805 obj = &element->package.elements[1];
806 if (obj->type != ACPI_TYPE_INTEGER) {
807 acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
812 cx.type = obj->integer.value;
814 * There are known cases in which the _CST output does not
815 * contain C1, so if the type of the first state found is not
816 * C1, leave an empty slot for C1 to be filled in later.
818 if (i == 1 && cx.type != ACPI_STATE_C1)
821 cx.address = reg->address;
822 cx.index = last_index + 1;
824 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
825 if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
827 * In the majority of cases _CST describes C1 as
828 * a FIXED_HARDWARE C-state, but if the command
829 * line forbids using MWAIT, use CSTATE_HALT for
832 if (cx.type == ACPI_STATE_C1 &&
833 boot_option_idle_override == IDLE_NOMWAIT) {
834 cx.entry_method = ACPI_CSTATE_HALT;
835 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
837 cx.entry_method = ACPI_CSTATE_FFH;
839 } else if (cx.type == ACPI_STATE_C1) {
841 * In the special case of C1, FIXED_HARDWARE can
842 * be handled by executing the HLT instruction.
844 cx.entry_method = ACPI_CSTATE_HALT;
845 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
847 acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
851 } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
852 cx.entry_method = ACPI_CSTATE_SYSTEMIO;
853 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
856 acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
861 if (cx.type == ACPI_STATE_C1)
864 obj = &element->package.elements[2];
865 if (obj->type != ACPI_TYPE_INTEGER) {
866 acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
871 cx.latency = obj->integer.value;
873 obj = &element->package.elements[3];
874 if (obj->type != ACPI_TYPE_INTEGER) {
875 acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
880 memcpy(&info->states[++last_index], &cx, sizeof(cx));
883 acpi_handle_info(handle, "Found %d idle states\n", last_index);
885 info->count = last_index;
888 kfree(buffer.pointer);
892 EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
893 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */