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Documentation / hwmon / coretemp

Based on kernel version 2.6.26. Page generated on 2008-07-16 21:12 EST.

1	Kernel driver coretemp
2	======================
3	
4	Supported chips:
5	  * All Intel Core family
6	    Prefix: 'coretemp'
7	    CPUID: family 0x6, models 0xe, 0xf, 0x16, 0x17
8	    Datasheet: Intel 64 and IA-32 Architectures Software Developer's Manual
9	               Volume 3A: System Programming Guide
10	               http://softwarecommunity.intel.com/Wiki/Mobility/720.htm
11	
12	Author: Rudolf Marek
13	
14	Description
15	-----------
16	
17	This driver permits reading temperature sensor embedded inside Intel Core CPU.
18	Temperature is measured in degrees Celsius and measurement resolution is
19	1 degree C. Valid temperatures are from 0 to TjMax degrees C, because
20	the actual value of temperature register is in fact a delta from TjMax.
21	
22	Temperature known as TjMax is the maximum junction temperature of processor.
23	Intel defines this temperature as 85C or 100C. At this temperature, protection
24	mechanism will perform actions to forcibly cool down the processor. Alarm
25	may be raised, if the temperature grows enough (more than TjMax) to trigger
26	the Out-Of-Spec bit. Following table summarizes the exported sysfs files:
27	
28	temp1_input	 - Core temperature (in millidegrees Celsius).
29	temp1_max	 - All cooling devices should be turned on (on Core2).
30	temp1_crit	 - Maximum junction temperature (in millidegrees Celsius).
31	temp1_crit_alarm - Set when Out-of-spec bit is set, never clears.
32			   Correct CPU operation is no longer guaranteed.
33	temp1_label	 - Contains string "Core X", where X is processor
34			   number.
35	
36	The TjMax temperature is set to 85 degrees C if undocumented model specific
37	register (UMSR) 0xee has bit 30 set. If not the TjMax is 100 degrees C as
38	(sometimes) documented in processor datasheet.
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