diff options
| author | Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> | 2013-05-17 23:42:03 +0000 |
|---|---|---|
| committer | Zhang Rui <rui.zhang@intel.com> | 2013-06-18 06:27:57 +0800 |
| commit | 23be63f48d928cd5a21db58f73c731357e895250 (patch) | |
| tree | 168ea644734f354824d8b97e614b205a70a99f17 /Documentation/thermal | |
| parent | f1a18a10566081abfce1649c2f3884b28fff7372 (diff) | |
Thermal: Documentation for x86 package temperature thermal driver
Added documentation describing details of the x86 package temperature
thermal driver.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Diffstat (limited to 'Documentation/thermal')
| -rw-r--r-- | Documentation/thermal/x86_pkg_temperature_thermal | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/Documentation/thermal/x86_pkg_temperature_thermal b/Documentation/thermal/x86_pkg_temperature_thermal new file mode 100644 index 00000000000..17a3a4c0a0c --- /dev/null +++ b/Documentation/thermal/x86_pkg_temperature_thermal @@ -0,0 +1,47 @@ +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 + + + + |