Thermal Specifications
Note that the 4-byte PCI configuration address and data defined above are sent in
standard PECI ordering with LSB first and MSB last.
6.3.2.5.2
Supported Responses
The typical client response is a passing FCS, a passing Completion Code and valid Data.
Under some conditions, the client’s response will indicate a failure.
Table 6-8.
PCIConfigWr() Response Definition
Response
Bad FCS
Meaning
Electrical error or AW FCS failure
Abort FCS
CC: 0x40
CC: 0x80
Illegal command formatting (mismatched RL/WL/Command Code)
Command passed, data is valid
Error causing a response timeout. Either due to a rare, internal timing condition or a
processor RESET condition or processor S1 state. Retry is appropriate outside of the RESET
or S1 states.
6.3.2.6
Mailbox
The PECI mailbox (“Mbx”) is a generic interface to access a wide variety of internal
processor states. A Mailbox request consists of sending a 1-byte request type and
4-byte data to the processor, followed by a 4-byte read of the response data. The
following sections describe the Mailbox capabilities as well as the usage semantics for
the MbxSend and MbxGet commands which are used to send and receive data.
6.3.2.6.1
Capabilities
Table 6-9.
Mailbox Command Summary (Sheet 1 of 2)
Request
MbxSend
Data
(dword)
MbxGet
Data
(dword)
Command
Name
Type
Code
(byte)
Description
Ping
0x00
0x01
0x00
0x00
Verify the operability / existence of the Mailbox.
Thermal
Status
Read/Clear
Log bit clear Thermal
mask
Read the thermal status register and optionally clear any log bits.
The thermal status has status and log bits indicating the state of
processor TCC activation, external FORCEPR_N assertion, and
Critical Temperature threshold crossings.
Status
Register
Counter
0x03
0x00
0x00
0x00
Snapshots all PECI-based counters
Snapshot
Counter Clear
Counter Read
0x04
0x05
0x00
Concurrently clear and restart all counters.
Counter
Number
Counter Data
Returns the counter number requested.
0: Total reference time
1: Total TCC Activation time counter
Icc-TDC Read
0x06
0x07
0x00
0x00
Icc-TDC
Returns the specified Icc-TDC of this part, in Amps.
Reads the thermal averaging constant.
Thermal Config
Data Read
Thermal
config data
Thermal Config
Data Write
0x08
0x09
0xB
Thermal
Config Data
0x00
Writes the thermal averaging constant.
Tcontrol Read
0x00
0x00
Tcontrol
Reads the fan speed control reference temperature, Tcontrol, in
PECI temperature format.
T-state
Throttling
Control Read
ACPI T-state
Control Word
Reads the PECI ACPI T-state throttling control word.
Datasheet Volume 1 of 2
129
INTEL [ INTEL ]
