/*
* 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");