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1 | Kernel driver: x86_pkg_temp_thermal | ||
2 | =================== | ||
3 | |||
4 | Supported chips: | ||
5 | * x86: with package level thermal management | ||
6 | (Verify using: CPUID.06H:EAX[bit 6] =1) | ||
7 | |||
8 | Authors: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> | ||
9 | |||
10 | Reference | ||
11 | --- | ||
12 | Intel® 64 and IA-32 Architectures Software Developer’s Manual (Jan, 2013): | ||
13 | Chapter 14.6: PACKAGE LEVEL THERMAL MANAGEMENT | ||
14 | |||
15 | Description | ||
16 | --------- | ||
17 | |||
18 | This driver register CPU digital temperature package level sensor as a thermal | ||
19 | zone with maximum two user mode configurable trip points. Number of trip points | ||
20 | depends on the capability of the package. Once the trip point is violated, | ||
21 | user mode can receive notification via thermal notification mechanism and can | ||
22 | take any action to control temperature. | ||
23 | |||
24 | |||
25 | Threshold management | ||
26 | -------------------- | ||
27 | Each package will register as a thermal zone under /sys/class/thermal. | ||
28 | Example: | ||
29 | /sys/class/thermal/thermal_zone1 | ||
30 | |||
31 | This contains two trip points: | ||
32 | - trip_point_0_temp | ||
33 | - trip_point_1_temp | ||
34 | |||
35 | User can set any temperature between 0 to TJ-Max temperature. Temperature units | ||
36 | are in milli-degree Celsius. Refer to "Documentation/thermal/sysfs-api.txt" for | ||
37 | thermal sys-fs details. | ||
38 | |||
39 | Any value other than 0 in these trip points, can trigger thermal notifications. | ||
40 | Setting 0, stops sending thermal notifications. | ||
41 | |||
42 | Thermal notifications: To get kobject-uevent notifications, set the thermal zone | ||
43 | policy to "user_space". For example: echo -n "user_space" > policy | ||
44 | |||
45 | |||
46 | |||
47 | |||