November 19, 2008 AMDTEMP 4

### NAME

amdtemp - AMD CPU on-die digital thermal sensor

### SYNOPSIS

amdtemp* at pci? dev ? function ?

### DESCRIPTION

The amdtemp driver provides support for the on-die digital thermal sensor present on AMD K8, AMD Barcelona, AMD Phenoms, and AMD Griffin CPUs.

These sensors were officially introduced in AMD K8 Revision F processors, and provide 0.5 degC accuracy. Precision was improved in Revision G chips, which provide two more bits for 0.25 degC steppings. Each core has two temperature sensors, and there are up to two cores per CPU socket.

AMD Barcelona, AMD Phenom, and AMD Griffin provide 0.125 degC accuracy and provide one temperature sensor for each CPU socket.

The amdtemp driver reports temperatures through the envsys(4) API.

Sensor | Units | Typical Use
```CPUN sensor0` | `uK` | `cpuN temperature`

### SEE ALSO

envsys(4), envstat(8), powerd(8)

### HISTORY

The amdtemp driver first appeared in OpenBSD4.4 named ``kate''. It was then ported to NetBSD5.0. The driver has been renamed with support for newer AMD CPUs.

### AUTHORS

The amdtemp driver was written by Constantine A. Murenin <cnst@openbsd.org> whilst at the University of Waterloo. It was adapted to NetBSD by Christoph Egger.