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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * acpi_processor.c - ACPI processor enumeration support4 *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 Corporation10 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>11 */12#define pr_fmt(fmt) "ACPI: " fmt13 14#include <linux/acpi.h>15#include <linux/cpu.h>16#include <linux/device.h>17#include <linux/dmi.h>18#include <linux/kernel.h>19#include <linux/module.h>20#include <linux/pci.h>21#include <linux/platform_device.h>22 23#include <acpi/processor.h>24 25#include <asm/cpu.h>26 27#include <xen/xen.h>28 29#include "internal.h"30 31DEFINE_PER_CPU(struct acpi_processor *, processors);32EXPORT_PER_CPU_SYMBOL(processors);33 34/* Errata Handling */35struct acpi_processor_errata errata __read_mostly;36EXPORT_SYMBOL_GPL(errata);37 38acpi_handle acpi_get_processor_handle(int cpu)39{40 struct acpi_processor *pr;41 42 pr = per_cpu(processors, cpu);43 if (pr)44 return pr->handle;45 46 return NULL;47}48 49static int acpi_processor_errata_piix4(struct pci_dev *dev)50{51 u8 value1 = 0;52 u8 value2 = 0;53 54 55 if (!dev)56 return -EINVAL;57 58 /*59 * Note that 'dev' references the PIIX4 ACPI Controller.60 */61 62 switch (dev->revision) {63 case 0:64 dev_dbg(&dev->dev, "Found PIIX4 A-step\n");65 break;66 case 1:67 dev_dbg(&dev->dev, "Found PIIX4 B-step\n");68 break;69 case 2:70 dev_dbg(&dev->dev, "Found PIIX4E\n");71 break;72 case 3:73 dev_dbg(&dev->dev, "Found PIIX4M\n");74 break;75 default:76 dev_dbg(&dev->dev, "Found unknown PIIX4\n");77 break;78 }79 80 switch (dev->revision) {81 82 case 0: /* PIIX4 A-step */83 case 1: /* PIIX4 B-step */84 /*85 * See specification changes #13 ("Manual Throttle Duty Cycle")86 * and #14 ("Enabling and Disabling Manual Throttle"), plus87 * erratum #5 ("STPCLK# Deassertion Time") from the January88 * 2002 PIIX4 specification update. Applies to only older89 * PIIX4 models.90 */91 errata.piix4.throttle = 1;92 fallthrough;93 94 case 2: /* PIIX4E */95 case 3: /* PIIX4M */96 /*97 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA98 * Livelock") from the January 2002 PIIX4 specification update.99 * Applies to all PIIX4 models.100 */101 102 /*103 * BM-IDE104 * ------105 * Find the PIIX4 IDE Controller and get the Bus Master IDE106 * Status register address. We'll use this later to read107 * each IDE controller's DMA status to make sure we catch all108 * DMA activity.109 */110 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,111 PCI_DEVICE_ID_INTEL_82371AB,112 PCI_ANY_ID, PCI_ANY_ID, NULL);113 if (dev) {114 errata.piix4.bmisx = pci_resource_start(dev, 4);115 pci_dev_put(dev);116 }117 118 /*119 * Type-F DMA120 * ----------121 * Find the PIIX4 ISA Controller and read the Motherboard122 * DMA controller's status to see if Type-F (Fast) DMA mode123 * is enabled (bit 7) on either channel. Note that we'll124 * disable C3 support if this is enabled, as some legacy125 * devices won't operate well if fast DMA is disabled.126 */127 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,128 PCI_DEVICE_ID_INTEL_82371AB_0,129 PCI_ANY_ID, PCI_ANY_ID, NULL);130 if (dev) {131 pci_read_config_byte(dev, 0x76, &value1);132 pci_read_config_byte(dev, 0x77, &value2);133 if ((value1 & 0x80) || (value2 & 0x80))134 errata.piix4.fdma = 1;135 pci_dev_put(dev);136 }137 138 break;139 }140 141 if (errata.piix4.bmisx)142 dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");143 if (errata.piix4.fdma)144 dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");145 146 return 0;147}148 149static int acpi_processor_errata(void)150{151 int result = 0;152 struct pci_dev *dev = NULL;153 154 /*155 * PIIX4156 */157 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,158 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,159 PCI_ANY_ID, NULL);160 if (dev) {161 result = acpi_processor_errata_piix4(dev);162 pci_dev_put(dev);163 }164 165 return result;166}167 168/* Create a platform device to represent a CPU frequency control mechanism. */169static void cpufreq_add_device(const char *name)170{171 struct platform_device *pdev;172 173 pdev = platform_device_register_simple(name, PLATFORM_DEVID_NONE, NULL, 0);174 if (IS_ERR(pdev))175 pr_info("%s device creation failed: %pe\n", name, pdev);176}177 178#ifdef CONFIG_X86179/* Check presence of Processor Clocking Control by searching for \_SB.PCCH. */180static void __init acpi_pcc_cpufreq_init(void)181{182 acpi_status status;183 acpi_handle handle;184 185 status = acpi_get_handle(NULL, "\\_SB", &handle);186 if (ACPI_FAILURE(status))187 return;188 189 if (acpi_has_method(handle, "PCCH"))190 cpufreq_add_device("pcc-cpufreq");191}192#else193static void __init acpi_pcc_cpufreq_init(void) {}194#endif /* CONFIG_X86 */195 196/* Initialization */197static DEFINE_PER_CPU(void *, processor_device_array);198 199static int acpi_processor_set_per_cpu(struct acpi_processor *pr,200 struct acpi_device *device)201{202 BUG_ON(pr->id >= nr_cpu_ids);203 204 /*205 * Buggy BIOS check.206 * ACPI id of processors can be reported wrongly by the BIOS.207 * Don't trust it blindly208 */209 if (per_cpu(processor_device_array, pr->id) != NULL &&210 per_cpu(processor_device_array, pr->id) != device) {211 dev_warn(&device->dev,212 "BIOS reported wrong ACPI id %d for the processor\n",213 pr->id);214 return -EINVAL;215 }216 /*217 * processor_device_array is not cleared on errors to allow buggy BIOS218 * checks.219 */220 per_cpu(processor_device_array, pr->id) = device;221 per_cpu(processors, pr->id) = pr;222 223 return 0;224}225 226#ifdef CONFIG_ACPI_HOTPLUG_CPU227static int acpi_processor_hotadd_init(struct acpi_processor *pr,228 struct acpi_device *device)229{230 int ret;231 232 if (invalid_phys_cpuid(pr->phys_id))233 return -ENODEV;234 235 cpu_maps_update_begin();236 cpus_write_lock();237 238 ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);239 if (ret)240 goto out;241 242 ret = acpi_processor_set_per_cpu(pr, device);243 if (ret) {244 acpi_unmap_cpu(pr->id);245 goto out;246 }247 248 ret = arch_register_cpu(pr->id);249 if (ret) {250 /* Leave the processor device array in place to detect buggy bios */251 per_cpu(processors, pr->id) = NULL;252 acpi_unmap_cpu(pr->id);253 goto out;254 }255 256 /*257 * CPU got hot-added, but cpu_data is not initialized yet. Do258 * cpu_idle/throttling initialization when the CPU gets online for259 * the first time.260 */261 pr_info("CPU%d has been hot-added\n", pr->id);262 263out:264 cpus_write_unlock();265 cpu_maps_update_done();266 return ret;267}268#else269static inline int acpi_processor_hotadd_init(struct acpi_processor *pr,270 struct acpi_device *device)271{272 return -ENODEV;273}274#endif /* CONFIG_ACPI_HOTPLUG_CPU */275 276static int acpi_processor_get_info(struct acpi_device *device)277{278 union acpi_object object = { 0 };279 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };280 struct acpi_processor *pr = acpi_driver_data(device);281 int device_declaration = 0;282 acpi_status status = AE_OK;283 static int cpu0_initialized;284 unsigned long long value;285 int ret;286 287 acpi_processor_errata();288 289 /*290 * Check to see if we have bus mastering arbitration control. This291 * is required for proper C3 usage (to maintain cache coherency).292 */293 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {294 pr->flags.bm_control = 1;295 dev_dbg(&device->dev, "Bus mastering arbitration control present\n");296 } else297 dev_dbg(&device->dev, "No bus mastering arbitration control\n");298 299 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {300 /* Declared with "Processor" statement; match ProcessorID */301 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);302 if (ACPI_FAILURE(status)) {303 dev_err(&device->dev,304 "Failed to evaluate processor object (0x%x)\n",305 status);306 return -ENODEV;307 }308 309 pr->acpi_id = object.processor.proc_id;310 } else {311 /*312 * Declared with "Device" statement; match _UID.313 */314 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,315 NULL, &value);316 if (ACPI_FAILURE(status)) {317 dev_err(&device->dev,318 "Failed to evaluate processor _UID (0x%x)\n",319 status);320 return -ENODEV;321 }322 device_declaration = 1;323 pr->acpi_id = value;324 }325 326 if (acpi_duplicate_processor_id(pr->acpi_id)) {327 if (pr->acpi_id == 0xff)328 dev_info_once(&device->dev,329 "Entry not well-defined, consider updating BIOS\n");330 else331 dev_err(&device->dev,332 "Failed to get unique processor _UID (0x%x)\n",333 pr->acpi_id);334 return -ENODEV;335 }336 337 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,338 pr->acpi_id);339 if (invalid_phys_cpuid(pr->phys_id))340 dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");341 342 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);343 if (!cpu0_initialized) {344 cpu0_initialized = 1;345 /*346 * Handle UP system running SMP kernel, with no CPU347 * entry in MADT348 */349 if (!acpi_has_cpu_in_madt() && invalid_logical_cpuid(pr->id) &&350 (num_online_cpus() == 1))351 pr->id = 0;352 /*353 * Check availability of Processor Performance Control by354 * looking at the presence of the _PCT object under the first355 * processor definition.356 */357 if (acpi_has_method(pr->handle, "_PCT"))358 cpufreq_add_device("acpi-cpufreq");359 }360 361 /*362 * This code is not called unless we know the CPU is present and363 * enabled. The two paths are:364 * a) Initially present CPUs on architectures that do not defer365 * their arch_register_cpu() calls until this point.366 * b) Hotplugged CPUs (enabled bit in _STA has transitioned from not367 * enabled to enabled)368 */369 if (!get_cpu_device(pr->id))370 ret = acpi_processor_hotadd_init(pr, device);371 else372 ret = acpi_processor_set_per_cpu(pr, device);373 if (ret)374 return ret;375 376 /*377 * On some boxes several processors use the same processor bus id.378 * But they are located in different scope. For example:379 * \_SB.SCK0.CPU0380 * \_SB.SCK1.CPU0381 * Rename the processor device bus id. And the new bus id will be382 * generated as the following format:383 * CPU+CPU ID.384 */385 sprintf(acpi_device_bid(device), "CPU%X", pr->id);386 dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);387 388 if (!object.processor.pblk_address)389 dev_dbg(&device->dev, "No PBLK (NULL address)\n");390 else if (object.processor.pblk_length != 6)391 dev_err(&device->dev, "Invalid PBLK length [%d]\n",392 object.processor.pblk_length);393 else {394 pr->throttling.address = object.processor.pblk_address;395 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;396 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;397 398 pr->pblk = object.processor.pblk_address;399 }400 401 /*402 * If ACPI describes a slot number for this CPU, we can use it to403 * ensure we get the right value in the "physical id" field404 * of /proc/cpuinfo405 */406 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);407 if (ACPI_SUCCESS(status))408 arch_fix_phys_package_id(pr->id, value);409 410 return 0;411}412 413/*414 * Do not put anything in here which needs the core to be online.415 * For example MSR access or setting up things which check for cpuinfo_x86416 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.417 * Such things have to be put in and set up by the processor driver's .probe().418 */419static int acpi_processor_add(struct acpi_device *device,420 const struct acpi_device_id *id)421{422 struct acpi_processor *pr;423 struct device *dev;424 int result = 0;425 426 if (!acpi_device_is_enabled(device))427 return -ENODEV;428 429 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);430 if (!pr)431 return -ENOMEM;432 433 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {434 result = -ENOMEM;435 goto err_free_pr;436 }437 438 pr->handle = device->handle;439 strscpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);440 strscpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);441 device->driver_data = pr;442 443 result = acpi_processor_get_info(device);444 if (result) /* Processor is not physically present or unavailable */445 goto err_clear_driver_data;446 447 dev = get_cpu_device(pr->id);448 if (!dev) {449 result = -ENODEV;450 goto err_clear_per_cpu;451 }452 453 result = acpi_bind_one(dev, device);454 if (result)455 goto err_clear_per_cpu;456 457 pr->dev = dev;458 459 /* Trigger the processor driver's .probe() if present. */460 if (device_attach(dev) >= 0)461 return 1;462 463 dev_err(dev, "Processor driver could not be attached\n");464 acpi_unbind_one(dev);465 466 err_clear_per_cpu:467 per_cpu(processors, pr->id) = NULL;468 err_clear_driver_data:469 device->driver_data = NULL;470 free_cpumask_var(pr->throttling.shared_cpu_map);471 err_free_pr:472 kfree(pr);473 return result;474}475 476#ifdef CONFIG_ACPI_HOTPLUG_CPU477/* Removal */478static void acpi_processor_post_eject(struct acpi_device *device)479{480 struct acpi_processor *pr;481 482 if (!device || !acpi_driver_data(device))483 return;484 485 pr = acpi_driver_data(device);486 if (pr->id >= nr_cpu_ids)487 goto out;488 489 /*490 * The only reason why we ever get here is CPU hot-removal. The CPU is491 * already offline and the ACPI device removal locking prevents it from492 * being put back online at this point.493 *494 * Unbind the driver from the processor device and detach it from the495 * ACPI companion object.496 */497 device_release_driver(pr->dev);498 acpi_unbind_one(pr->dev);499 500 cpu_maps_update_begin();501 cpus_write_lock();502 503 /* Remove the CPU. */504 arch_unregister_cpu(pr->id);505 acpi_unmap_cpu(pr->id);506 507 /* Clean up. */508 per_cpu(processor_device_array, pr->id) = NULL;509 per_cpu(processors, pr->id) = NULL;510 511 cpus_write_unlock();512 cpu_maps_update_done();513 514 try_offline_node(cpu_to_node(pr->id));515 516 out:517 free_cpumask_var(pr->throttling.shared_cpu_map);518 kfree(pr);519}520#endif /* CONFIG_ACPI_HOTPLUG_CPU */521 522#ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC523bool __init processor_physically_present(acpi_handle handle)524{525 int cpuid, type;526 u32 acpi_id;527 acpi_status status;528 acpi_object_type acpi_type;529 unsigned long long tmp;530 union acpi_object object = {};531 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };532 533 status = acpi_get_type(handle, &acpi_type);534 if (ACPI_FAILURE(status))535 return false;536 537 switch (acpi_type) {538 case ACPI_TYPE_PROCESSOR:539 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);540 if (ACPI_FAILURE(status))541 return false;542 acpi_id = object.processor.proc_id;543 break;544 case ACPI_TYPE_DEVICE:545 status = acpi_evaluate_integer(handle, METHOD_NAME__UID,546 NULL, &tmp);547 if (ACPI_FAILURE(status))548 return false;549 acpi_id = tmp;550 break;551 default:552 return false;553 }554 555 if (xen_initial_domain())556 /*557 * When running as a Xen dom0 the number of processors Linux558 * sees can be different from the real number of processors on559 * the system, and we still need to execute _PDC or _OSC for560 * all of them.561 */562 return xen_processor_present(acpi_id);563 564 type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;565 cpuid = acpi_get_cpuid(handle, type, acpi_id);566 567 return !invalid_logical_cpuid(cpuid);568}569 570/* vendor specific UUID indicating an Intel platform */571static u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";572 573static acpi_status __init acpi_processor_osc(acpi_handle handle, u32 lvl,574 void *context, void **rv)575{576 u32 capbuf[2] = {};577 struct acpi_osc_context osc_context = {578 .uuid_str = sb_uuid_str,579 .rev = 1,580 .cap.length = 8,581 .cap.pointer = capbuf,582 };583 acpi_status status;584 585 if (!processor_physically_present(handle))586 return AE_OK;587 588 arch_acpi_set_proc_cap_bits(&capbuf[OSC_SUPPORT_DWORD]);589 590 status = acpi_run_osc(handle, &osc_context);591 if (ACPI_FAILURE(status))592 return status;593 594 kfree(osc_context.ret.pointer);595 596 return AE_OK;597}598 599static bool __init acpi_early_processor_osc(void)600{601 acpi_status status;602 603 acpi_proc_quirk_mwait_check();604 605 status = acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,606 ACPI_UINT32_MAX, acpi_processor_osc, NULL,607 NULL, NULL);608 if (ACPI_FAILURE(status))609 return false;610 611 status = acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_osc,612 NULL, NULL);613 if (ACPI_FAILURE(status))614 return false;615 616 return true;617}618 619void __init acpi_early_processor_control_setup(void)620{621 if (acpi_early_processor_osc()) {622 pr_debug("_OSC evaluated successfully for all CPUs\n");623 } else {624 pr_debug("_OSC evaluation for CPUs failed, trying _PDC\n");625 acpi_early_processor_set_pdc();626 }627}628#endif629 630/*631 * The following ACPI IDs are known to be suitable for representing as632 * processor devices.633 */634static const struct acpi_device_id processor_device_ids[] = {635 636 { ACPI_PROCESSOR_OBJECT_HID, },637 { ACPI_PROCESSOR_DEVICE_HID, },638 639 { }640};641 642static struct acpi_scan_handler processor_handler = {643 .ids = processor_device_ids,644 .attach = acpi_processor_add,645#ifdef CONFIG_ACPI_HOTPLUG_CPU646 .post_eject = acpi_processor_post_eject,647#endif648 .hotplug = {649 .enabled = true,650 },651};652 653static int acpi_processor_container_attach(struct acpi_device *dev,654 const struct acpi_device_id *id)655{656 return 1;657}658 659static const struct acpi_device_id processor_container_ids[] = {660 { ACPI_PROCESSOR_CONTAINER_HID, },661 { }662};663 664static struct acpi_scan_handler processor_container_handler = {665 .ids = processor_container_ids,666 .attach = acpi_processor_container_attach,667};668 669/* The number of the unique processor IDs */670static int nr_unique_ids __initdata;671 672/* The number of the duplicate processor IDs */673static int nr_duplicate_ids;674 675/* Used to store the unique processor IDs */676static int unique_processor_ids[] __initdata = {677 [0 ... NR_CPUS - 1] = -1,678};679 680/* Used to store the duplicate processor IDs */681static int duplicate_processor_ids[] = {682 [0 ... NR_CPUS - 1] = -1,683};684 685static void __init processor_validated_ids_update(int proc_id)686{687 int i;688 689 if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)690 return;691 692 /*693 * Firstly, compare the proc_id with duplicate IDs, if the proc_id is694 * already in the IDs, do nothing.695 */696 for (i = 0; i < nr_duplicate_ids; i++) {697 if (duplicate_processor_ids[i] == proc_id)698 return;699 }700 701 /*702 * Secondly, compare the proc_id with unique IDs, if the proc_id is in703 * the IDs, put it in the duplicate IDs.704 */705 for (i = 0; i < nr_unique_ids; i++) {706 if (unique_processor_ids[i] == proc_id) {707 duplicate_processor_ids[nr_duplicate_ids] = proc_id;708 nr_duplicate_ids++;709 return;710 }711 }712 713 /*714 * Lastly, the proc_id is a unique ID, put it in the unique IDs.715 */716 unique_processor_ids[nr_unique_ids] = proc_id;717 nr_unique_ids++;718}719 720static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,721 u32 lvl,722 void *context,723 void **rv)724{725 acpi_status status;726 acpi_object_type acpi_type;727 unsigned long long uid;728 union acpi_object object = { 0 };729 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };730 731 status = acpi_get_type(handle, &acpi_type);732 if (ACPI_FAILURE(status))733 return status;734 735 switch (acpi_type) {736 case ACPI_TYPE_PROCESSOR:737 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);738 if (ACPI_FAILURE(status))739 goto err;740 uid = object.processor.proc_id;741 break;742 743 case ACPI_TYPE_DEVICE:744 status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);745 if (ACPI_FAILURE(status))746 goto err;747 break;748 default:749 goto err;750 }751 752 processor_validated_ids_update(uid);753 return AE_OK;754 755err:756 /* Exit on error, but don't abort the namespace walk */757 acpi_handle_info(handle, "Invalid processor object\n");758 return AE_OK;759 760}761 762static void __init acpi_processor_check_duplicates(void)763{764 /* check the correctness for all processors in ACPI namespace */765 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,766 ACPI_UINT32_MAX,767 acpi_processor_ids_walk,768 NULL, NULL, NULL);769 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,770 NULL, NULL);771}772 773bool acpi_duplicate_processor_id(int proc_id)774{775 int i;776 777 /*778 * compare the proc_id with duplicate IDs, if the proc_id is already779 * in the duplicate IDs, return true, otherwise, return false.780 */781 for (i = 0; i < nr_duplicate_ids; i++) {782 if (duplicate_processor_ids[i] == proc_id)783 return true;784 }785 return false;786}787 788void __init acpi_processor_init(void)789{790 acpi_processor_check_duplicates();791 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");792 acpi_scan_add_handler(&processor_container_handler);793 acpi_pcc_cpufreq_init();794}795 796#ifdef CONFIG_ACPI_PROCESSOR_CSTATE797/**798 * acpi_processor_claim_cst_control - Request _CST control from the platform.799 */800bool acpi_processor_claim_cst_control(void)801{802 static bool cst_control_claimed;803 acpi_status status;804 805 if (!acpi_gbl_FADT.cst_control || cst_control_claimed)806 return true;807 808 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,809 acpi_gbl_FADT.cst_control, 8);810 if (ACPI_FAILURE(status)) {811 pr_warn("ACPI: Failed to claim processor _CST control\n");812 return false;813 }814 815 cst_control_claimed = true;816 return true;817}818EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);819 820/**821 * acpi_processor_evaluate_cst - Evaluate the processor _CST control method.822 * @handle: ACPI handle of the processor object containing the _CST.823 * @cpu: The numeric ID of the target CPU.824 * @info: Object write the C-states information into.825 *826 * Extract the C-state information for the given CPU from the output of the _CST827 * control method under the corresponding ACPI processor object (or processor828 * device object) and populate @info with it.829 *830 * If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke831 * acpi_processor_ffh_cstate_probe() to verify them and update the832 * cpu_cstate_entry data for @cpu.833 */834int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,835 struct acpi_processor_power *info)836{837 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };838 union acpi_object *cst;839 acpi_status status;840 u64 count;841 int last_index = 0;842 int i, ret = 0;843 844 status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);845 if (ACPI_FAILURE(status)) {846 acpi_handle_debug(handle, "No _CST\n");847 return -ENODEV;848 }849 850 cst = buffer.pointer;851 852 /* There must be at least 2 elements. */853 if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {854 acpi_handle_warn(handle, "Invalid _CST output\n");855 ret = -EFAULT;856 goto end;857 }858 859 count = cst->package.elements[0].integer.value;860 861 /* Validate the number of C-states. */862 if (count < 1 || count != cst->package.count - 1) {863 acpi_handle_warn(handle, "Inconsistent _CST data\n");864 ret = -EFAULT;865 goto end;866 }867 868 for (i = 1; i <= count; i++) {869 union acpi_object *element;870 union acpi_object *obj;871 struct acpi_power_register *reg;872 struct acpi_processor_cx cx;873 874 /*875 * If there is not enough space for all C-states, skip the876 * excess ones and log a warning.877 */878 if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {879 acpi_handle_warn(handle,880 "No room for more idle states (limit: %d)\n",881 ACPI_PROCESSOR_MAX_POWER - 1);882 break;883 }884 885 memset(&cx, 0, sizeof(cx));886 887 element = &cst->package.elements[i];888 if (element->type != ACPI_TYPE_PACKAGE) {889 acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",890 i, element->type);891 continue;892 }893 894 if (element->package.count != 4) {895 acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",896 i, element->package.count);897 continue;898 }899 900 obj = &element->package.elements[0];901 902 if (obj->type != ACPI_TYPE_BUFFER) {903 acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",904 i, obj->type);905 continue;906 }907 908 reg = (struct acpi_power_register *)obj->buffer.pointer;909 910 obj = &element->package.elements[1];911 if (obj->type != ACPI_TYPE_INTEGER) {912 acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",913 i, obj->type);914 continue;915 }916 917 cx.type = obj->integer.value;918 /*919 * There are known cases in which the _CST output does not920 * contain C1, so if the type of the first state found is not921 * C1, leave an empty slot for C1 to be filled in later.922 */923 if (i == 1 && cx.type != ACPI_STATE_C1)924 last_index = 1;925 926 cx.address = reg->address;927 cx.index = last_index + 1;928 929 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {930 if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {931 /*932 * In the majority of cases _CST describes C1 as933 * a FIXED_HARDWARE C-state, but if the command934 * line forbids using MWAIT, use CSTATE_HALT for935 * C1 regardless.936 */937 if (cx.type == ACPI_STATE_C1 &&938 boot_option_idle_override == IDLE_NOMWAIT) {939 cx.entry_method = ACPI_CSTATE_HALT;940 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");941 } else {942 cx.entry_method = ACPI_CSTATE_FFH;943 }944 } else if (cx.type == ACPI_STATE_C1) {945 /*946 * In the special case of C1, FIXED_HARDWARE can947 * be handled by executing the HLT instruction.948 */949 cx.entry_method = ACPI_CSTATE_HALT;950 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");951 } else {952 acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",953 i);954 continue;955 }956 } else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {957 cx.entry_method = ACPI_CSTATE_SYSTEMIO;958 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",959 cx.address);960 } else {961 acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",962 i, reg->space_id);963 continue;964 }965 966 if (cx.type == ACPI_STATE_C1)967 cx.valid = 1;968 969 obj = &element->package.elements[2];970 if (obj->type != ACPI_TYPE_INTEGER) {971 acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",972 i, obj->type);973 continue;974 }975 976 cx.latency = obj->integer.value;977 978 obj = &element->package.elements[3];979 if (obj->type != ACPI_TYPE_INTEGER) {980 acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",981 i, obj->type);982 continue;983 }984 985 memcpy(&info->states[++last_index], &cx, sizeof(cx));986 }987 988 acpi_handle_debug(handle, "Found %d idle states\n", last_index);989 990 info->count = last_index;991 992end:993 kfree(buffer.pointer);994 995 return ret;996}997EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);998#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */999