Datasheet

Interfaces

54 Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 v2 Product Families

Datasheet Volume One of Two

2.5.2.6.20 Package Thermal Status Read / Clear

The Thermal Status Read provides information on package level thermal status. Data

includes:

• Thermal Control Circuit (TCC) activation

• Bidirectional PROCHOT_N signal assertion

•Critical Temperature

Both status and sticky log bits are managed in this status word. All sticky log bits are

set upon a rising edge of the associated status bit and the log bits are cleared only by

Thermal Status reads or a processor reset. A read of the Thermal Status word always

includes a log bit clear mask that allows the host to clear any or all of the log bits that

it is interested in tracking.

A bit set to ‘0’ in the log bit clear mask will result in clearing the associated log bit. If a

mask bit is set to ‘0’ and that bit is not a legal mask, a failing completion code will be

returned. A bit set to ‘1’ is ignored and results in no change to any sticky log bits. For

example, to clear the TCC Activation Log bit and retain all other log bits, the Thermal

Status Read should send a mask of 0xFFFFFFFD.

2.5.2.6.21 Thermal Averaging Constant Write / Read

This feature allows the PECI host to control the window over which the estimated

processor PECI temperature is filtered. The host may configure this window as a power

of two. For example, programming a value of 5 results in a filtering window of 2

or 32

samples. The maximum programmable value is 8 or 256 samples. Programming a

value of zero would disable the PECI temperature averaging feature. The default value

of the thermal averaging constant is 4 which translates to an averaging window size of

or 16 samples. More details on the PECI temperature filtering function can be found

in Section 2.5.7.3.

Figure 2-30. Temperature Target Read

Figure 2-31. Thermal Status Word

Critical Temperature Log

Critical Temperature Status

Bidirectional PROCHOT# Log

Bidirectional PROCHOT#

Status

TCC Activation Log

TCC Activation Status

6543210

Reserved