| 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/thermal/sysfs-api.txt" 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 | |