linux-yocto/Documentation/hwmon/k10temp
Clemens Ladisch aa4790a628 hwmon: (k10temp) add support for AMD Family 12h/14h CPUs
Add the PCI ID to support the internal temperature sensor of the
AMD "Llano" and "Brazos" processor families.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: stable@kernel.org # ca86828: x86, AMD, PCI: Add AMD northbridge PCI device
Cc: stable@kernel.org
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
2011-02-18 06:14:24 -08:00

3.3 KiB

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 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.

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.