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;
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.
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
103 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
104 PCI_DEVICE_ID_INTEL_82371AB,
105 PCI_ANY_ID, PCI_ANY_ID, NULL);
107 errata.piix4.bmisx = pci_resource_start(dev, 4);
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.
120 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
121 PCI_DEVICE_ID_INTEL_82371AB_0,
122 PCI_ANY_ID, PCI_ANY_ID, NULL);
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;
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"));
144 static int acpi_processor_errata(void)
147 struct pci_dev *dev = NULL;
152 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
153 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
156 result = acpi_processor_errata_piix4(dev);
163 /* --------------------------------------------------------------------------
165 -------------------------------------------------------------------------- */
167 #ifdef CONFIG_ACPI_HOTPLUG_CPU
168 int __weak acpi_map_cpu(acpi_handle handle,
169 phys_cpuid_t physid, u32 acpi_id, int *pcpu)
174 int __weak acpi_unmap_cpu(int cpu)
179 int __weak arch_register_cpu(int cpu)
184 void __weak arch_unregister_cpu(int cpu) {}
186 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
188 unsigned long long sta;
192 if (invalid_phys_cpuid(pr->phys_id))
195 status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
196 if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
199 cpu_maps_update_begin();
202 ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
206 ret = arch_register_cpu(pr->id);
208 acpi_unmap_cpu(pr->id);
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.
217 pr_info("CPU%d has been hot-added\n", pr->id);
218 pr->flags.need_hotplug_init = 1;
222 cpu_maps_update_done();
226 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
230 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
232 static int acpi_processor_get_info(struct acpi_device *device)
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;
242 acpi_processor_errata();
245 * Check to see if we have bus mastering arbitration control. This
246 * is required for proper C3 usage (to maintain cache coherency).
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"));
253 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
254 "No bus mastering arbitration control\n"));
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",
266 pr->acpi_id = object.processor.proc_id;
269 * Declared with "Device" statement; match _UID.
270 * Note that we don't handle string _UIDs yet.
272 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
274 if (ACPI_FAILURE(status)) {
275 dev_err(&device->dev,
276 "Failed to evaluate processor _UID (0x%x)\n",
280 device_declaration = 1;
284 if (acpi_duplicate_processor_id(pr->acpi_id)) {
285 if (pr->acpi_id == 0xff)
286 dev_info_once(&device->dev,
287 "Entry not well-defined, consider updating BIOS\n");
289 dev_err(&device->dev,
290 "Failed to get unique processor _UID (0x%x)\n",
295 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
297 if (invalid_phys_cpuid(pr->phys_id))
298 acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
300 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
301 if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
302 cpu0_initialized = 1;
304 * Handle UP system running SMP kernel, with no CPU
307 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
312 * Extra Processor objects may be enumerated on MP systems with
313 * less than the max # of CPUs. They should be ignored _iff
314 * they are physically not present.
316 * NOTE: Even if the processor has a cpuid, it may not be present
317 * because cpuid <-> apicid mapping is persistent now.
319 if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
320 int ret = acpi_processor_hotadd_init(pr);
326 * On some boxes several processors use the same processor bus id.
327 * But they are located in different scope. For example:
330 * Rename the processor device bus id. And the new bus id will be
331 * generated as the following format:
334 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
335 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
338 if (!object.processor.pblk_address)
339 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
340 else if (object.processor.pblk_length != 6)
341 dev_err(&device->dev, "Invalid PBLK length [%d]\n",
342 object.processor.pblk_length);
344 pr->throttling.address = object.processor.pblk_address;
345 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
346 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
348 pr->pblk = object.processor.pblk_address;
352 * If ACPI describes a slot number for this CPU, we can use it to
353 * ensure we get the right value in the "physical id" field
356 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
357 if (ACPI_SUCCESS(status))
358 arch_fix_phys_package_id(pr->id, value);
364 * Do not put anything in here which needs the core to be online.
365 * For example MSR access or setting up things which check for cpuinfo_x86
366 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
367 * Such things have to be put in and set up by the processor driver's .probe().
369 static DEFINE_PER_CPU(void *, processor_device_array);
371 static int acpi_processor_add(struct acpi_device *device,
372 const struct acpi_device_id *id)
374 struct acpi_processor *pr;
378 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
382 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
387 pr->handle = device->handle;
388 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
389 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
390 device->driver_data = pr;
392 result = acpi_processor_get_info(device);
393 if (result) /* Processor is not physically present or unavailable */
396 BUG_ON(pr->id >= nr_cpu_ids);
400 * ACPI id of processors can be reported wrongly by the BIOS.
401 * Don't trust it blindly
403 if (per_cpu(processor_device_array, pr->id) != NULL &&
404 per_cpu(processor_device_array, pr->id) != device) {
405 dev_warn(&device->dev,
406 "BIOS reported wrong ACPI id %d for the processor\n",
408 /* Give up, but do not abort the namespace scan. */
412 * processor_device_array is not cleared on errors to allow buggy BIOS
415 per_cpu(processor_device_array, pr->id) = device;
416 per_cpu(processors, pr->id) = pr;
418 dev = get_cpu_device(pr->id);
424 result = acpi_bind_one(dev, device);
430 /* Trigger the processor driver's .probe() if present. */
431 if (device_attach(dev) >= 0)
434 dev_err(dev, "Processor driver could not be attached\n");
435 acpi_unbind_one(dev);
438 free_cpumask_var(pr->throttling.shared_cpu_map);
439 device->driver_data = NULL;
440 per_cpu(processors, pr->id) = NULL;
446 #ifdef CONFIG_ACPI_HOTPLUG_CPU
447 /* --------------------------------------------------------------------------
449 -------------------------------------------------------------------------- */
451 static void acpi_processor_remove(struct acpi_device *device)
453 struct acpi_processor *pr;
455 if (!device || !acpi_driver_data(device))
458 pr = acpi_driver_data(device);
459 if (pr->id >= nr_cpu_ids)
463 * The only reason why we ever get here is CPU hot-removal. The CPU is
464 * already offline and the ACPI device removal locking prevents it from
465 * being put back online at this point.
467 * Unbind the driver from the processor device and detach it from the
468 * ACPI companion object.
470 device_release_driver(pr->dev);
471 acpi_unbind_one(pr->dev);
474 per_cpu(processor_device_array, pr->id) = NULL;
475 per_cpu(processors, pr->id) = NULL;
477 cpu_maps_update_begin();
480 /* Remove the CPU. */
481 arch_unregister_cpu(pr->id);
482 acpi_unmap_cpu(pr->id);
485 cpu_maps_update_done();
487 try_offline_node(cpu_to_node(pr->id));
490 free_cpumask_var(pr->throttling.shared_cpu_map);
493 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
496 static bool acpi_hwp_native_thermal_lvt_set;
497 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
502 u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
504 struct acpi_osc_context osc_context = {
505 .uuid_str = sb_uuid_str,
508 .cap.pointer = capbuf,
511 if (acpi_hwp_native_thermal_lvt_set)
512 return AE_CTRL_TERMINATE;
515 capbuf[1] = 0x1000; /* set bit 12 */
517 if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
518 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
519 u32 *capbuf_ret = osc_context.ret.pointer;
521 if (capbuf_ret[1] & 0x1000) {
522 acpi_handle_info(handle,
523 "_OSC native thermal LVT Acked\n");
524 acpi_hwp_native_thermal_lvt_set = true;
527 kfree(osc_context.ret.pointer);
533 void __init acpi_early_processor_osc(void)
535 if (boot_cpu_has(X86_FEATURE_HWP)) {
536 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
538 acpi_hwp_native_thermal_lvt_osc,
540 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
541 acpi_hwp_native_thermal_lvt_osc,
548 * The following ACPI IDs are known to be suitable for representing as
551 static const struct acpi_device_id processor_device_ids[] = {
553 { ACPI_PROCESSOR_OBJECT_HID, },
554 { ACPI_PROCESSOR_DEVICE_HID, },
559 static struct acpi_scan_handler processor_handler = {
560 .ids = processor_device_ids,
561 .attach = acpi_processor_add,
562 #ifdef CONFIG_ACPI_HOTPLUG_CPU
563 .detach = acpi_processor_remove,
570 static int acpi_processor_container_attach(struct acpi_device *dev,
571 const struct acpi_device_id *id)
576 static const struct acpi_device_id processor_container_ids[] = {
577 { ACPI_PROCESSOR_CONTAINER_HID, },
581 static struct acpi_scan_handler processor_container_handler = {
582 .ids = processor_container_ids,
583 .attach = acpi_processor_container_attach,
586 /* The number of the unique processor IDs */
587 static int nr_unique_ids __initdata;
589 /* The number of the duplicate processor IDs */
590 static int nr_duplicate_ids;
592 /* Used to store the unique processor IDs */
593 static int unique_processor_ids[] __initdata = {
594 [0 ... NR_CPUS - 1] = -1,
597 /* Used to store the duplicate processor IDs */
598 static int duplicate_processor_ids[] = {
599 [0 ... NR_CPUS - 1] = -1,
602 static void __init processor_validated_ids_update(int proc_id)
606 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
610 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is
611 * already in the IDs, do nothing.
613 for (i = 0; i < nr_duplicate_ids; i++) {
614 if (duplicate_processor_ids[i] == proc_id)
619 * Secondly, compare the proc_id with unique IDs, if the proc_id is in
620 * the IDs, put it in the duplicate IDs.
622 for (i = 0; i < nr_unique_ids; i++) {
623 if (unique_processor_ids[i] == proc_id) {
624 duplicate_processor_ids[nr_duplicate_ids] = proc_id;
631 * Lastly, the proc_id is a unique ID, put it in the unique IDs.
633 unique_processor_ids[nr_unique_ids] = proc_id;
637 static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
643 acpi_object_type acpi_type;
644 unsigned long long uid;
645 union acpi_object object = { 0 };
646 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
648 status = acpi_get_type(handle, &acpi_type);
649 if (ACPI_FAILURE(status))
653 case ACPI_TYPE_PROCESSOR:
654 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
655 if (ACPI_FAILURE(status))
657 uid = object.processor.proc_id;
660 case ACPI_TYPE_DEVICE:
661 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
662 if (ACPI_FAILURE(status))
669 processor_validated_ids_update(uid);
673 /* Exit on error, but don't abort the namespace walk */
674 acpi_handle_info(handle, "Invalid processor object\n");
679 static void __init acpi_processor_check_duplicates(void)
681 /* check the correctness for all processors in ACPI namespace */
682 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
684 acpi_processor_ids_walk,
686 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
690 bool acpi_duplicate_processor_id(int proc_id)
695 * compare the proc_id with duplicate IDs, if the proc_id is already
696 * in the duplicate IDs, return true, otherwise, return false.
698 for (i = 0; i < nr_duplicate_ids; i++) {
699 if (duplicate_processor_ids[i] == proc_id)
705 void __init acpi_processor_init(void)
707 acpi_processor_check_duplicates();
708 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
709 acpi_scan_add_handler(&processor_container_handler);