diff options
Diffstat (limited to 'kernel/drivers/acpi/processor_driver.c')
-rw-r--r-- | kernel/drivers/acpi/processor_driver.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/kernel/drivers/acpi/processor_driver.c b/kernel/drivers/acpi/processor_driver.c new file mode 100644 index 000000000..d9f71581b --- /dev/null +++ b/kernel/drivers/acpi/processor_driver.c @@ -0,0 +1,307 @@ +/* + * 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; + 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"); |