/* * processor_driver.c - ACPI Processor Driver * * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> * - Added processor hotplug support * Copyright (C) 2013, Intel Corporation * Rafael J. Wysocki <rafael.j.wysocki@intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/cpufreq.h> #include <linux/cpu.h> #include <linux/cpuidle.h> #include <linux/slab.h> #include <linux/acpi.h> #include <acpi/processor.h> #include "internal.h" #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80 #define ACPI_PROCESSOR_NOTIFY_POWER 0x81 #define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82 #define _COMPONENT ACPI_PROCESSOR_COMPONENT ACPI_MODULE_NAME("processor_driver"); MODULE_AUTHOR("Paul Diefenbaugh"); MODULE_DESCRIPTION("ACPI Processor Driver"); MODULE_LICENSE("GPL"); static int acpi_processor_start(struct device *dev); static int acpi_processor_stop(struct device *dev); static const struct acpi_device_id processor_device_ids[] = { {ACPI_PROCESSOR_OBJECT_HID, 0}, {ACPI_PROCESSOR_DEVICE_HID, 0}, {"", 0}, }; MODULE_DEVICE_TABLE(acpi, processor_device_ids); static struct device_driver acpi_processor_driver = { .name = "processor", .bus = &cpu_subsys, .acpi_match_table = processor_device_ids, .probe = acpi_processor_start, .remove = acpi_processor_stop, }; static void acpi_processor_notify(acpi_handle handle, u32 event, void *data) { struct acpi_device *device = data; struct acpi_processor *pr; int saved; if (device->handle != handle) return; pr = acpi_driver_data(device); if (!pr) return; switch (event) { case ACPI_PROCESSOR_NOTIFY_PERFORMANCE: saved = pr->performance_platform_limit; acpi_processor_ppc_has_changed(pr, 1); if (saved == pr->performance_platform_limit) break; acpi_bus_generate_netlink_event(device->pnp.device_class, dev_name(&device->dev), event, pr->performance_platform_limit); break; case ACPI_PROCESSOR_NOTIFY_POWER: acpi_processor_cst_has_changed(pr); acpi_bus_generate_netlink_event(device->pnp.device_class, dev_name(&device->dev), event, 0); break; case ACPI_PROCESSOR_NOTIFY_THROTTLING: acpi_processor_tstate_has_changed(pr); acpi_bus_generate_netlink_event(device->pnp.device_class, dev_name(&device->dev), event, 0); break; default: ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Unsupported event [0x%x]\n", event)); break; } return; } static int __acpi_processor_start(struct acpi_device *device); static int acpi_cpu_soft_notify(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; struct acpi_processor *pr = per_cpu(processors, cpu); struct acpi_device *device; /* * CPU_STARTING and CPU_DYING must not sleep. Return here since * acpi_bus_get_device() may sleep. */ if (action == CPU_STARTING || action == CPU_DYING) return NOTIFY_DONE; if (!pr || acpi_bus_get_device(pr->handle, &device)) return NOTIFY_DONE; if (action == CPU_ONLINE) { /* * CPU got physically hotplugged and onlined for the first time: * Initialize missing things. */ if (pr->flags.need_hotplug_init) { int ret; pr_info("Will online and init hotplugged CPU: %d\n", pr->id); pr->flags.need_hotplug_init = 0; ret = __acpi_processor_start(device); WARN(ret, "Failed to start CPU: %d\n", pr->id); } else { /* Normal CPU soft online event. */ acpi_processor_ppc_has_changed(pr, 0); acpi_processor_hotplug(pr); acpi_processor_reevaluate_tstate(pr, action); acpi_processor_tstate_has_changed(pr); } } else if (action == CPU_DEAD) { /* Invalidate flag.throttling after the CPU is offline. */ acpi_processor_reevaluate_tstate(pr, action); } return NOTIFY_OK; } static struct notifier_block __refdata acpi_cpu_notifier = { .notifier_call = acpi_cpu_soft_notify, }; static int __acpi_processor_start(struct acpi_device *device) { struct acpi_processor *pr = acpi_driver_data(device); acpi_status status; int result = 0; if (!pr) return -ENODEV; if (pr->flags.need_hotplug_init) return 0; #ifdef CONFIG_CPU_FREQ acpi_processor_ppc_has_changed(pr, 0); #endif acpi_processor_get_throttling_info(pr); if (pr->flags.throttling) pr->flags.limit = 1; if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver) acpi_processor_power_init(pr); pr->cdev = thermal_cooling_device_register("Processor", device, &processor_cooling_ops); if (IS_ERR(pr->cdev)) { result = PTR_ERR(pr->cdev); goto err_power_exit; } dev_dbg(&device->dev, "registered as cooling_device%d\n", pr->cdev->id); result = sysfs_create_link(&device->dev.kobj, &pr->cdev->device.kobj, "thermal_cooling"); if (result) { dev_err(&device->dev, "Failed to create sysfs link 'thermal_cooling'\n"); goto err_thermal_unregister; } result = sysfs_create_link(&pr->cdev->device.kobj, &device->dev.kobj, "device"); if (result) { dev_err(&pr->cdev->device, "Failed to create sysfs link 'device'\n"); goto err_remove_sysfs_thermal; } status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, acpi_processor_notify, device); if (ACPI_SUCCESS(status)) return 0; sysfs_remove_link(&pr->cdev->device.kobj, "device"); err_remove_sysfs_thermal: sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); err_thermal_unregister: thermal_cooling_device_unregister(pr->cdev); err_power_exit: acpi_processor_power_exit(pr); return result; } static int acpi_processor_start(struct device *dev) { struct acpi_device *device = ACPI_COMPANION(dev); if (!device) return -ENODEV; return __acpi_processor_start(device); } static int acpi_processor_stop(struct device *dev) { struct acpi_device *device = ACPI_COMPANION(dev); struct acpi_processor *pr; if (!device) return 0; acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, acpi_processor_notify); pr = acpi_driver_data(device); if (!pr) return 0; acpi_processor_power_exit(pr); if (pr->cdev) { sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); sysfs_remove_link(&pr->cdev->device.kobj, "device"); thermal_cooling_device_unregister(pr->cdev); pr->cdev = NULL; } return 0; } /* * We keep the driver loaded even when ACPI is not running. * This is needed for the powernow-k8 driver, that works even without * ACPI, but needs symbols from this driver */ static int __init acpi_processor_driver_init(void) { int result = 0; if (acpi_disabled) return 0; result = driver_register(&acpi_processor_driver); if (result < 0) return result; acpi_processor_syscore_init(); register_hotcpu_notifier(&acpi_cpu_notifier); acpi_thermal_cpufreq_init(); acpi_processor_ppc_init(); acpi_processor_throttling_init(); return 0; } static void __exit acpi_processor_driver_exit(void) { if (acpi_disabled) return; acpi_processor_ppc_exit(); acpi_thermal_cpufreq_exit(); unregister_hotcpu_notifier(&acpi_cpu_notifier); acpi_processor_syscore_exit(); driver_unregister(&acpi_processor_driver); } module_init(acpi_processor_driver_init); module_exit(acpi_processor_driver_exit); MODULE_ALIAS("processor");