| Rudolf Marek | d58ee056 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 1 | Kernel driver coretemp |
| 2 | ====================== |
| 3 | |
| 4 | Supported chips: |
| 5 | * All Intel Core family |
| 6 | Prefix: 'coretemp' |
| Rudolf Marek | eccfed4 | 2009-09-23 22:59:42 +0200 | [diff] [blame] | 7 | CPUID: family 0x6, models 0xe (Pentium M DC), 0xf (Core 2 DC 65nm), |
| 8 | 0x16 (Core 2 SC 65nm), 0x17 (Penryn 45nm), |
| Huaxu Wan | fa08acd | 2009-09-23 22:59:43 +0200 | [diff] [blame] | 9 | 0x1a (Nehalem), 0x1c (Atom), 0x1e (Lynnfield) |
| Rudolf Marek | d58ee056 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 10 | Datasheet: Intel 64 and IA-32 Architectures Software Developer's Manual |
| 11 | Volume 3A: System Programming Guide |
| Rudolf Marek | ae77015 | 2008-01-18 00:50:04 +0100 | [diff] [blame] | 12 | http://softwarecommunity.intel.com/Wiki/Mobility/720.htm |
| Rudolf Marek | d58ee056 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 13 | |
| 14 | Author: Rudolf Marek |
| 15 | |
| 16 | Description |
| 17 | ----------- |
| 18 | |
| 19 | This driver permits reading temperature sensor embedded inside Intel Core CPU. |
| 20 | Temperature is measured in degrees Celsius and measurement resolution is |
| 21 | 1 degree C. Valid temperatures are from 0 to TjMax degrees C, because |
| 22 | the actual value of temperature register is in fact a delta from TjMax. |
| 23 | |
| 24 | Temperature known as TjMax is the maximum junction temperature of processor. |
| 25 | Intel defines this temperature as 85C or 100C. At this temperature, protection |
| 26 | mechanism will perform actions to forcibly cool down the processor. Alarm |
| 27 | may be raised, if the temperature grows enough (more than TjMax) to trigger |
| 28 | the Out-Of-Spec bit. Following table summarizes the exported sysfs files: |
| 29 | |
| 30 | temp1_input - Core temperature (in millidegrees Celsius). |
| Rudolf Marek | 6369a288 | 2008-01-18 00:42:54 +0100 | [diff] [blame] | 31 | temp1_max - All cooling devices should be turned on (on Core2). |
| 32 | temp1_crit - Maximum junction temperature (in millidegrees Celsius). |
| Rudolf Marek | d58ee056 | 2007-05-08 17:22:02 +0200 | [diff] [blame] | 33 | temp1_crit_alarm - Set when Out-of-spec bit is set, never clears. |
| 34 | Correct CPU operation is no longer guaranteed. |
| 35 | temp1_label - Contains string "Core X", where X is processor |
| 36 | number. |
| 37 | |
| 38 | The TjMax temperature is set to 85 degrees C if undocumented model specific |
| 39 | register (UMSR) 0xee has bit 30 set. If not the TjMax is 100 degrees C as |
| 40 | (sometimes) documented in processor datasheet. |