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1 | Kernel driver coretemp |
2 | ====================== | |
3 | ||
4 | Supported chips: | |
5 | * All Intel Core family | |
6 | Prefix: 'coretemp' | |
ae770152 | 7 | CPUID: family 0x6, models 0xe, 0xf, 0x16, 0x17 |
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8 | Datasheet: Intel 64 and IA-32 Architectures Software Developer's Manual |
9 | Volume 3A: System Programming Guide | |
ae770152 | 10 | http://softwarecommunity.intel.com/Wiki/Mobility/720.htm |
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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). | |
6369a288 RM |
29 | temp1_max - All cooling devices should be turned on (on Core2). |
30 | temp1_crit - Maximum junction temperature (in millidegrees Celsius). | |
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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. |