mirror of
https://github.com/torvalds/linux.git
synced 2024-12-26 12:52:30 +00:00
eaf7b46083
The file contents mostly describes driver internals. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
56 lines
1.5 KiB
ReStructuredText
56 lines
1.5 KiB
ReStructuredText
===================================
|
||
Kernel driver: x86_pkg_temp_thermal
|
||
===================================
|
||
|
||
Supported chips:
|
||
|
||
* x86: with package level thermal management
|
||
|
||
(Verify using: CPUID.06H:EAX[bit 6] =1)
|
||
|
||
Authors: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
|
||
|
||
Reference
|
||
---------
|
||
|
||
Intel® 64 and IA-32 Architectures Software Developer’s Manual (Jan, 2013):
|
||
Chapter 14.6: PACKAGE LEVEL THERMAL MANAGEMENT
|
||
|
||
Description
|
||
-----------
|
||
|
||
This driver register CPU digital temperature package level sensor as a thermal
|
||
zone with maximum two user mode configurable trip points. Number of trip points
|
||
depends on the capability of the package. Once the trip point is violated,
|
||
user mode can receive notification via thermal notification mechanism and can
|
||
take any action to control temperature.
|
||
|
||
|
||
Threshold management
|
||
--------------------
|
||
Each package will register as a thermal zone under /sys/class/thermal.
|
||
|
||
Example::
|
||
|
||
/sys/class/thermal/thermal_zone1
|
||
|
||
This contains two trip points:
|
||
|
||
- trip_point_0_temp
|
||
- trip_point_1_temp
|
||
|
||
User can set any temperature between 0 to TJ-Max temperature. Temperature units
|
||
are in milli-degree Celsius. Refer to "Documentation/driver-api/thermal/sysfs-api.rst" for
|
||
thermal sys-fs details.
|
||
|
||
Any value other than 0 in these trip points, can trigger thermal notifications.
|
||
Setting 0, stops sending thermal notifications.
|
||
|
||
Thermal notifications:
|
||
To get kobject-uevent notifications, set the thermal zone
|
||
policy to "user_space".
|
||
|
||
For example::
|
||
|
||
echo -n "user_space" > policy
|