// SPDX-License-Identifier: GPL-2.0-or-later/* * 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> */ #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 ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED	0x85 MODULE_AUTHOR("Paul Diefenbaugh");MODULE_DESCRIPTION("ACPI Processor Driver");MODULE_LICENSE("GPL"); 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,	.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, ev_data = 0; 	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);		ev_data = pr->performance_platform_limit;		if (saved == ev_data)			return; 		break;	case ACPI_PROCESSOR_NOTIFY_POWER:		acpi_processor_power_state_has_changed(pr);		break;	case ACPI_PROCESSOR_NOTIFY_THROTTLING:		acpi_processor_tstate_has_changed(pr);		break;	case ACPI_PROCESSOR_NOTIFY_HIGEST_PERF_CHANGED:		cpufreq_update_limits(pr->id);		break;	default:		acpi_handle_debug(handle, "Unsupported event [0x%x]\n", event);		return;	} 	acpi_bus_generate_netlink_event("processor", dev_name(&device->dev),					event, ev_data);} static int __acpi_processor_start(struct acpi_device *device); static int acpi_soft_cpu_online(unsigned int cpu){	struct acpi_processor *pr = per_cpu(processors, cpu);	struct acpi_device *device; 	if (!pr)		return 0; 	device = acpi_fetch_acpi_dev(pr->handle);	if (!device)		return 0; 	/*	 * CPU got physically hotplugged and onlined for the first time:	 * Initialize missing things.	 */	if (!pr->flags.previously_online) {		int ret; 		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, false);		acpi_processor_tstate_has_changed(pr);	}	return 0;} static int acpi_soft_cpu_dead(unsigned int cpu){	struct acpi_processor *pr = per_cpu(processors, cpu); 	if (!pr || !acpi_fetch_acpi_dev(pr->handle))		return 0; 	acpi_processor_reevaluate_tstate(pr, true);	return 0;} #ifdef CONFIG_ACPI_CPU_FREQ_PSSstatic void acpi_pss_perf_init(struct acpi_processor *pr){	acpi_processor_ppc_has_changed(pr, 0); 	acpi_processor_get_throttling_info(pr); 	if (pr->flags.throttling)		pr->flags.limit = 1;}#elsestatic inline void acpi_pss_perf_init(struct acpi_processor *pr) {}#endif /* CONFIG_ACPI_CPU_FREQ_PSS */ 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; 	result = acpi_cppc_processor_probe(pr);	if (result && !IS_ENABLED(CONFIG_ACPI_CPU_FREQ_PSS))		dev_dbg(&device->dev, "CPPC data invalid or not present\n"); 	acpi_processor_power_init(pr); 	acpi_pss_perf_init(pr); 	result = acpi_processor_thermal_init(pr, device);	if (result)		goto err_power_exit; 	status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,					     acpi_processor_notify, device);	if (!ACPI_SUCCESS(status)) {		result = -ENODEV;		goto err_thermal_exit;	}	pr->flags.previously_online = 1; 	return 0; err_thermal_exit:	acpi_processor_thermal_exit(pr, device);err_power_exit:	acpi_processor_power_exit(pr);	return result;} 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); 	acpi_cppc_processor_exit(pr); 	acpi_processor_thermal_exit(pr, device); 	return 0;} bool acpi_processor_cpufreq_init; static int acpi_processor_notifier(struct notifier_block *nb,				   unsigned long event, void *data){	struct cpufreq_policy *policy = data; 	if (event == CPUFREQ_CREATE_POLICY) {		acpi_thermal_cpufreq_init(policy);		acpi_processor_ppc_init(policy);	} else if (event == CPUFREQ_REMOVE_POLICY) {		acpi_processor_ppc_exit(policy);		acpi_thermal_cpufreq_exit(policy);	} 	return 0;} static struct notifier_block acpi_processor_notifier_block = {	.notifier_call = acpi_processor_notifier,}; void __weak acpi_processor_init_invariance_cppc(void){ } /* * 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 enum cpuhp_state hp_online;static int __init acpi_processor_driver_init(void){	int result = 0; 	if (acpi_disabled)		return 0; 	if (!cpufreq_register_notifier(&acpi_processor_notifier_block,				       CPUFREQ_POLICY_NOTIFIER)) {		acpi_processor_cpufreq_init = true;		acpi_processor_ignore_ppc_init();	} 	acpi_processor_register_idle_driver(); 	result = driver_register(&acpi_processor_driver);	if (result < 0)		goto unregister_idle_drv; 	result = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,				   "acpi/cpu-drv:online",				   acpi_soft_cpu_online, NULL);	if (result < 0)		goto err;	hp_online = result;	cpuhp_setup_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD, "acpi/cpu-drv:dead",				  NULL, acpi_soft_cpu_dead); 	acpi_processor_throttling_init(); 	/*	 * Frequency invariance calculations on AMD platforms can't be run until	 * after acpi_cppc_processor_probe() has been called for all online CPUs	 */	acpi_processor_init_invariance_cppc(); 	acpi_idle_rescan_dead_smt_siblings(); 	return 0; err:	driver_unregister(&acpi_processor_driver); unregister_idle_drv:	acpi_processor_unregister_idle_driver(); 	return result;} static void __exit acpi_processor_driver_exit(void){	if (acpi_disabled)		return; 	if (acpi_processor_cpufreq_init) {		cpufreq_unregister_notifier(&acpi_processor_notifier_block,					    CPUFREQ_POLICY_NOTIFIER);		acpi_processor_cpufreq_init = false;	} 	cpuhp_remove_state_nocalls(hp_online);	cpuhp_remove_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD);	driver_unregister(&acpi_processor_driver);	acpi_processor_unregister_idle_driver();} module_init(acpi_processor_driver_init);module_exit(acpi_processor_driver_exit); MODULE_ALIAS("processor");