/* * 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_COMPONENTACPI_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;	action &= ~CPU_TASKS_FROZEN; 	/*	 * 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");