Updated AMD P-State Driver Posted For Improving Linux Power Efficiency

Written by Michael Larabel in AMD on 19 November 2021 at 06:55 AM EST. 31 Comments
A fourth iteration of the AMD P-State CPU frequency scaling driver patches for Linux have been sent out for review and testing.

This is the amd-pstate driver aiming for better power efficiency on Linux by leveraging ACPI CPPC found with Zen 2 and newer processors. Valve collaborated with AMD on the creation of this new driver that aims to be superior to the generic ACPI CPUFreq driver currently used by AMD processors. This driver has been undergoing public review since September with aims to make it to the mainline kernel.

With today's amd-pstate v4 series, the driver has been re-based against the upstream Linux 5.15 state for the power management branch, cleaning up some of the code, introduction of an AMD CPPC support library, an option to disable shared memory support, and other low-level improvements to the driver code. The v4 series can be found via the kernel mailing list.

It's been a revision or two ago since I last tested the amd-pstate driver to mixed success, so will take these fresh patches for a spin shortly. The timing of this driver though makes it out of reach for mainlining in Linux 5.16 but we'll see if it's squared away in time for v5.17.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of Phoronix.com and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via MichaelLarabel.com.

Popular News This Week