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→Axel Embedded Linux Kit (XELK)
*125°C for automotive parts.
====U-Boot====
At U-Boot level, automatic boot procedure is halted until Tj is smaller than (following temperatures might seem excessively low but they take into account the intrinsic poor precision of the temperature sensor to provide a reasonable safe margin):
*80°C for commercial parts
*110°C for automotive parts.
At Linux level, a more sophisticated protection mechanism is implemented. Please refer to the following sections for more details.
====XELK 1.x.y series====
Practically speaking, this mechanism makes use of two different thresholds, denoted as <code>trip_point0</code> and <code>trip_point1</code>. When Tj reaches <code>trip_point0</code>, Linux kernel scales down processor frequency:
<pre>
thermal thermal_zone0: critical temperature reached(100 C),shutting down
</pre>
Trip point thresholds can be accessed via <code>sysfs</code> interface from user space.
The following example shows how to read the values of the trip points:
</pre>
For more details about this functionality, please refer to <code>Documentation/thermal/sysfs-api.txt</code> in the kernel sources. ====XELK 2.x.y series====TBD==Related links==*[[Power_consumption_(AxelLite)|Power consumption of AxelLite SOM]]*[[FAQs_(Axel)|SoC frequency management, see also ]]*[[FAQs_Power_management_(Axel)|this pagePower management of Axel product family]].
