Cold Trip Points Proposed For The Linux Kernel's Thermal Handling

The Linux kernel's thermal driver has the obvious notion of hot and critically-hot trip points while to this point there hasn't been the opposite: cold trip points (events) but that's finally been proposed as we approach the end of 2023.

A majority of the time the concern by engineers is hardware getting too hot and needing to regulate that via down-clocking components, turning off additional circuitry, or other safeguards in the event of components becoming too warm. But with Linux being very common in the embedded space and being found deployed in all sorts of industrial environments, there's also the possibility in some conditions of hardware becoming too cold.

Developer Christian Marangi has proposed adding to Linux's thermal core code support for "cold" and "critical_cold" trip points. This mainline Linux kernel support for cold trip points would make it easier to support devices within specialized environments. If a cold trip point is reached, the system could respond by increasing voltages / bumping up to a higher performance state, enabling an attached heater in some specialized environments, or taking other steps to deal with the low temperatures.

Those interested in the proposed cold/critical_cold trip points for the Linux thermal code can see the suggested patches on the kernel mailing list.