Intel Coffee Lake & Cannonlake Thermal Support In Linux 4.15

While Intel Coffee Lake hardware is shipping already, a few bits of tardy kernel code for these "8th Gen Core" CPUs is only hitting the Linux 4.15 kernel. The Intel DRM driver is most notably enabling Coffee Lake graphics by default in 4.15, but there's also some thermal code now landing among other changes now happening.

Zhang Rui sent in the thermal updates for Linux 4.15 on Thursday and they include late additions for Coffee Lake but at the same time the relevant additions for Cannonlake that will be shipping in 2018 as the next-gen Intel CPUs.

On the Coffee Lake front, the respective PCI IDs were added to the int340x thermal driver. The int340x driver is used by some newer laptops that via ACPI expose thermal sensors outside of the core CPU. They are exposed as the INT3400 ACPI device object and hence the driver's name. The int340x support isn't critical, but allows for exposing these additional thermal sensors to user-space.

With Cannonlake, there is now int340x support too. Additionally, the Intel PCH Thermal driver also now has Cannonlake support. The Intel PCH thermal driver is for reporting the Intel PCH temperature, trip points, and related information.

These changes and many other thermal updates for Linux 4.15 can be found via this pull request.