Thermal Reporting Over System Management Link 1 Interface (Smlink1) - Intel 6 SERIES CHIPSET - DATASHEET 01-2011 Datasheet

Functional Description
5.21.1.1.1 Recommended Programming for Available Trip Points
There may be a ±2 °C offset due to thermal gradient between the hot-spot and the
location of the thermal sensor. Trip points should be programmed to account for this
temperature offset between the hot-spot T
Aux Trip Points should be programmed for software and firmware control using
interrupts.
Hot Trip Point should be set to throttle at 108 °C (T
adjustments. Hot trip points should also be programmed for a software response.
Catastrophic Trip Point should be set to halt operation to avoid maximum T
120 C.
Note: Crossing a trip point in either direction may generate several types of interrupts. Each
trip point has a register that can be programmed to select the type of interrupt to be
generated. Crossing a trip point is implemented as edge detection on each trip point to
generate the interrupts.
5.21.1.1.2 Thermal Sensor Accuracy (T
T
accuracy
±10 °C for temperatures from 45 °C – 90 °C. The PCH may not operate above
+108 °C. This value is based on product characterization and is not ensured by
manufacturing test.
Software has the ability to program the Tcat, Thot, and Taux trip points, but these trip
points should be selected with consideration for the thermal sensor accuracy and the
quality of the platform thermal solution. Overly conservative (unnecessarily low)
temperature settings may unnecessarily degrade performance due to frequent
throttling, while overly aggressive (dangerously high) temperature settings may fail to
protect the part against permanent thermal damage.
5.21.2 Thermal Reporting Over System Management Link 1
Interface (SMLink1)
SMLink1 interface in the PCH is the SMBus link to an optional external controller. A
SMBus protocol is defined on the PCH to allow compatible devices such as Embedded
Controller (EC) or SIO to obtain system thermal data from sensors integrated into
components on the system using the SMLink1 interface. The sensors that can be
monitored using the SMLink1 include those in the processor, PCH and DIMMs with
sensors implemented. This solution allows an external device or controller to use the
system thermal data for system thermal management.
Note: To enable Thermal Reporting, the Thermal Data Reporting enable and PCH/DIMM
temperature read enables have to be set in the Thermal Reporting Control (TRC)
Register (See
Datasheet
accuracy
for the PCH is ±5 °C in the temperature range 90 °C to 120 °C. T
Section 22.2 for details on Register)
and the thermal sensor.
j,max
) due to DTS trim accuracy
j,max
)
of about
j
is
accuracy
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