| 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. |
