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Rudolf Marekd58ee052007-05-08 17:22:02 +02001Kernel driver coretemp
2======================
3
4Supported chips:
5 * All Intel Core family
6 Prefix: 'coretemp'
Rudolf Marekae770152008-01-18 00:50:04 +01007 CPUID: family 0x6, models 0xe, 0xf, 0x16, 0x17
Rudolf Marekd58ee052007-05-08 17:22:02 +02008 Datasheet: Intel 64 and IA-32 Architectures Software Developer's Manual
9 Volume 3A: System Programming Guide
Rudolf Marekae770152008-01-18 00:50:04 +010010 http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
Rudolf Marekd58ee052007-05-08 17:22:02 +020011
12Author: Rudolf Marek
13
14Description
15-----------
16
17This driver permits reading temperature sensor embedded inside Intel Core CPU.
18Temperature is measured in degrees Celsius and measurement resolution is
191 degree C. Valid temperatures are from 0 to TjMax degrees C, because
20the actual value of temperature register is in fact a delta from TjMax.
21
22Temperature known as TjMax is the maximum junction temperature of processor.
23Intel defines this temperature as 85C or 100C. At this temperature, protection
24mechanism will perform actions to forcibly cool down the processor. Alarm
25may be raised, if the temperature grows enough (more than TjMax) to trigger
26the Out-Of-Spec bit. Following table summarizes the exported sysfs files:
27
28temp1_input - Core temperature (in millidegrees Celsius).
Rudolf Marek6369a2882008-01-18 00:42:54 +010029temp1_max - All cooling devices should be turned on (on Core2).
30temp1_crit - Maximum junction temperature (in millidegrees Celsius).
Rudolf Marekd58ee052007-05-08 17:22:02 +020031temp1_crit_alarm - Set when Out-of-spec bit is set, never clears.
32 Correct CPU operation is no longer guaranteed.
33temp1_label - Contains string "Core X", where X is processor
34 number.
35
36The TjMax temperature is set to 85 degrees C if undocumented model specific
37register (UMSR) 0xee has bit 30 set. If not the TjMax is 100 degrees C as
38(sometimes) documented in processor datasheet.