linux-hardened/include/linux/thermal.h
Matthew Garrett 03a971a289 thermal: support forcing support for passive cooling
Due to poor thermal design or Linux driving hardware outside its thermal
envelope, some systems will reach critical temperature and shut down
under high load. This patch adds support for forcing a polling-based
passive trip point if the firmware doesn't provide one. The assumption
is made that the processor is the most practical means to reduce the
dynamic heat generation, so hitting the passive thermal limit will cause
the CPU to be throttled until the temperature stabalises around the
defined value.

UI is provided via a "passive" sysfs entry in the thermal zone
directory. It accepts a decimal value in millidegrees celsius, or "0" to
disable the functionality. Default behaviour is for this functionality
to be disabled.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-03-27 16:58:22 -04:00

150 lines
4.6 KiB
C

/*
* thermal.h ($Revision: 0 $)
*
* Copyright (C) 2008 Intel Corp
* Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
* Copyright (C) 2008 Sujith Thomas <sujith.thomas@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; version 2 of the License.
*
* 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#ifndef __THERMAL_H__
#define __THERMAL_H__
#include <linux/idr.h>
#include <linux/device.h>
#include <linux/workqueue.h>
struct thermal_zone_device;
struct thermal_cooling_device;
enum thermal_device_mode {
THERMAL_DEVICE_DISABLED = 0,
THERMAL_DEVICE_ENABLED,
};
enum thermal_trip_type {
THERMAL_TRIP_ACTIVE = 0,
THERMAL_TRIP_PASSIVE,
THERMAL_TRIP_HOT,
THERMAL_TRIP_CRITICAL,
};
struct thermal_zone_device_ops {
int (*bind) (struct thermal_zone_device *,
struct thermal_cooling_device *);
int (*unbind) (struct thermal_zone_device *,
struct thermal_cooling_device *);
int (*get_temp) (struct thermal_zone_device *, unsigned long *);
int (*get_mode) (struct thermal_zone_device *,
enum thermal_device_mode *);
int (*set_mode) (struct thermal_zone_device *,
enum thermal_device_mode);
int (*get_trip_type) (struct thermal_zone_device *, int,
enum thermal_trip_type *);
int (*get_trip_temp) (struct thermal_zone_device *, int,
unsigned long *);
int (*get_crit_temp) (struct thermal_zone_device *, unsigned long *);
int (*notify) (struct thermal_zone_device *, int,
enum thermal_trip_type);
};
struct thermal_cooling_device_ops {
int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
};
#define THERMAL_TRIPS_NONE -1
#define THERMAL_MAX_TRIPS 12
#define THERMAL_NAME_LENGTH 20
struct thermal_cooling_device {
int id;
char type[THERMAL_NAME_LENGTH];
struct device device;
void *devdata;
struct thermal_cooling_device_ops *ops;
struct list_head node;
};
#define KELVIN_TO_CELSIUS(t) (long)(((long)t-2732 >= 0) ? \
((long)t-2732+5)/10 : ((long)t-2732-5)/10)
#define CELSIUS_TO_KELVIN(t) ((t)*10+2732)
#if defined(CONFIG_THERMAL_HWMON)
/* thermal zone devices with the same type share one hwmon device */
struct thermal_hwmon_device {
char type[THERMAL_NAME_LENGTH];
struct device *device;
int count;
struct list_head tz_list;
struct list_head node;
};
struct thermal_hwmon_attr {
struct device_attribute attr;
char name[16];
};
#endif
struct thermal_zone_device {
int id;
char type[THERMAL_NAME_LENGTH];
struct device device;
void *devdata;
int trips;
int tc1;
int tc2;
int passive_delay;
int polling_delay;
int last_temperature;
bool passive;
unsigned int forced_passive;
struct thermal_zone_device_ops *ops;
struct list_head cooling_devices;
struct idr idr;
struct mutex lock; /* protect cooling devices list */
struct list_head node;
struct delayed_work poll_queue;
#if defined(CONFIG_THERMAL_HWMON)
struct list_head hwmon_node;
struct thermal_hwmon_device *hwmon;
struct thermal_hwmon_attr temp_input; /* hwmon sys attr */
struct thermal_hwmon_attr temp_crit; /* hwmon sys attr */
#endif
};
struct thermal_zone_device *thermal_zone_device_register(char *, int, void *,
struct
thermal_zone_device_ops
*, int tc1, int tc2,
int passive_freq,
int polling_freq);
void thermal_zone_device_unregister(struct thermal_zone_device *);
int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
struct thermal_cooling_device *);
int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
struct thermal_cooling_device *);
void thermal_zone_device_update(struct thermal_zone_device *);
struct thermal_cooling_device *thermal_cooling_device_register(char *, void *,
struct
thermal_cooling_device_ops
*);
void thermal_cooling_device_unregister(struct thermal_cooling_device *);
#endif /* __THERMAL_H__ */