AMD Zen Thermal/Power Reporting Improvements Could Hit Linux 5.6 But More Testing Needed

Last week I eagerly reported on Ryzen CPUs on Linux finally seeing CCD temperatures and current/voltage reporting thanks to new patches to the k10temp driver by Google's Guenter Roeck who oversees the kernel's hardware monitoring "HWMON" subsystem. The patches seem to be working well and are tentatively queued in hwmon-next, but more testing is still needed.

Those k10temp patches were quickly revised and currently at version two. They seem to be working well in the extra thermal and power reporting where capable for Zen/Zen+/Zen2 CPUs.

Excitingly, on Sunday I noticed the AMD thermal/power driver improvements did land in hwmon-next normally meaning they are queued and ready for the upcoming kernel merge window, Linux 5.6

However, in communicating with Guenter in my testing results of the patches, he indicated he still would like to see more tests/confirmation that these driver improvements are working fine. He wants to get as much feedback as possible and then make up his mind whether to submit for Linux 5.6.

I have tested the k10temp patches on a number of AMD Zen/Zen+/Zen2 systems so far and have not run into any problems. Those wanting to test these patches and share their feedback can find the current v2 patches here as well as the contact information for the mailing lists to volley your data (or if you can't be bothered to do that, post your sensors output in the forums as a comment and I can relay the data as well).

To hopefully motivate more to test these patches, here is my Ubuntu/Debian kernel build of Linux 5.5 patched with the v2 k10temp patches, if you were holding off on testing to avoid building your own kernel. Of course use at your own risk but so far these driver patches have been working great.

Here's to hoping that these long-awaited AMD thermal/power CPU reporting improvements can make it into Linux 5.6!