AMD P-State Driver Improvements Getting Ready For Linux 6.14

While Linux 6.13-rc1 was only released this past Sunday and there is around two months to go until the start of the Linux 6.14 kernel cycle, AMD P-State driver improvements are already beginning to collect for this next kernel cycle.

Mario Limonciello of AMD's Linux engineering team sent out a set of improvements and clean-ups for the AMD P-State CPU frequency scaling driver that are targeting this next Linux 6.14 kernel cycle.

The patches add trace event support for EPP perf updates, utilizing the boost numerator as the highest perf again after a recent semantic change, caching the Energy Performance Preference (EPP) value, and setting a different default EPP policy from EPYC and Ryzen processors.

Mario Limonciello explained with these initial patches for the AMD P-State driver for Linux 6.14:

"This series started as work on the behavior around boost numerator that was changed in the last few kernels to make it more expected.

As part of the process, of these improvements I found various other optimizations that made a lot of sense in the context of the code.

While I was working on the issues I found it was really helpful to have ftrace for EPP, so it introduces that as well.

Lastly a bug was reported requesting that amd-pstate default policy be changed for client systems that don't use other software after bootup so it includes that change too."

We'll see what more AMD P-State CPU frequency scaling driver improvements come about in roughly the next two months ahead of the v6.14 merge window.