d58ee056cc
Documentation for the coretemp driver. Signed-off-by: Rudolf Marek <r.marek@assembler.cz> Signed-off-by: Jean Delvare <khali@linux-fr.org>
36 lines
1.5 KiB
Text
36 lines
1.5 KiB
Text
Kernel driver coretemp
|
|
======================
|
|
|
|
Supported chips:
|
|
* All Intel Core family
|
|
Prefix: 'coretemp'
|
|
CPUID: family 0x6, models 0xe, 0xf
|
|
Datasheet: Intel 64 and IA-32 Architectures Software Developer's Manual
|
|
Volume 3A: System Programming Guide
|
|
|
|
Author: Rudolf Marek
|
|
|
|
Description
|
|
-----------
|
|
|
|
This driver permits reading temperature sensor embedded inside Intel Core CPU.
|
|
Temperature is measured in degrees Celsius and measurement resolution is
|
|
1 degree C. Valid temperatures are from 0 to TjMax degrees C, because
|
|
the actual value of temperature register is in fact a delta from TjMax.
|
|
|
|
Temperature known as TjMax is the maximum junction temperature of processor.
|
|
Intel defines this temperature as 85C or 100C. At this temperature, protection
|
|
mechanism will perform actions to forcibly cool down the processor. Alarm
|
|
may be raised, if the temperature grows enough (more than TjMax) to trigger
|
|
the Out-Of-Spec bit. Following table summarizes the exported sysfs files:
|
|
|
|
temp1_input - Core temperature (in millidegrees Celsius).
|
|
temp1_crit - Maximum junction temperature (in millidegrees Celsius).
|
|
temp1_crit_alarm - Set when Out-of-spec bit is set, never clears.
|
|
Correct CPU operation is no longer guaranteed.
|
|
temp1_label - Contains string "Core X", where X is processor
|
|
number.
|
|
|
|
The TjMax temperature is set to 85 degrees C if undocumented model specific
|
|
register (UMSR) 0xee has bit 30 set. If not the TjMax is 100 degrees C as
|
|
(sometimes) documented in processor datasheet.
|