Kernel driver k10temp

Supported chips:

Author: Clemens Ladisch <clemens@ladisch.de>

Description

This driver permits reading of the internal temperature sensor of AMD Family 10h/11h/12h/14h/15h/16h processors.

All these processors have a sensor, but on those for Socket F or AM2+, the sensor may return inconsistent values (erratum 319). The driver will refuse to load on these revisions unless you specify the “force=1” module parameter.

Due to technical reasons, the driver can detect only the mainboard’s socket type, not the processor’s actual capabilities. Therefore, if you are using an AM3 processor on an AM2+ mainboard, you can safely use the “force=1” parameter.

For CPUs older than Family 17h, there is one temperature measurement value, available as temp1_input in sysfs. It is measured in degrees Celsius with a resolution of 1/8th degree. Please note that it is defined as a relative value; to quote the AMD manual:

Tctl is the processor temperature control value, used by the platform to
control cooling systems. Tctl is a non-physical temperature on an
arbitrary scale measured in degrees. It does _not_ represent an actual
physical temperature like die or case temperature. Instead, it specifies
the processor temperature relative to the point at which the system must
supply the maximum cooling for the processor's specified maximum case
temperature and maximum thermal power dissipation.

The maximum value for Tctl is available in the file temp1_max.

If the BIOS has enabled hardware temperature control, the threshold at which the processor will throttle itself to avoid damage is available in temp1_crit and temp1_crit_hyst.

On some AMD CPUs, there is a difference between the die temperature (Tdie) and the reported temperature (Tctl). Tdie is the real measured temperature, and Tctl is used for fan control. While Tctl is always available as temp1_input, the driver exports Tdie temperature as temp2_input for those CPUs which support it.

Models from 17h family report relative temperature, the driver aims to compensate and report the real temperature.

On Family 17h and Family 18h CPUs, additional temperature sensors may report Core Complex Die (CCD) temperatures. Up to 8 such temperatures are reported as temp{3..10}_input, labeled Tccd{1..8}. Actual support depends on the CPU variant.

Various Family 17h and 18h CPUs report voltage and current telemetry information. The following attributes may be reported.

Attribute Label Description =============== ======= ================ in0_input Vcore Core voltage in1_input Vsoc SoC voltage curr1_input Icore Core current curr2_input Isoc SoC current =============== ======= ================

Current values are raw (unscaled) as reported by the CPU. Core current is reported as multiples of 1A / LSB. SoC is reported as multiples of 0.25A / LSB. The real current is board specific. Reported currents should be seen as rough guidance, and should be scaled using sensors3.conf as appropriate for a given board.