Linux 5.8 Sees Many Power Management Updates, Including Another Intel P-State Change

Linux power management / ACPI maintainer Rafael Wysocki of Intel has sent in the usual big batch of PM/ACPI changes for the next version of the kernel, Linux 5.8.

Changes on the power management front for the Linux 5.8 kernel include:

- The Intel P-State driver will now start in passive mode by default for systems without Hardware P-States (HWP). This has been expected and follows other recent P-State work, including the use of the schedutil governor by default.

- Support for switching CPUidle governors at run-time.

- ACPI Suspend-to-idle will now print more debug messages for helping to analyze issues when they come up.

- Documentation added covering the Intel SpeedSelect sysfs interfaces.

- Intel Elkhart Lake support has been added to the Intel RAPL (Runtime Average Power Limiting) power-capping driver.

The full list of power management changes for Linux 5.8 via the PM pull.

Sadly the power management material for Linux 5.8 doesn't include the long-awaited AMD CPPC CPUfreq driver or any other CPPC improvements for Zen 2 support.

The ACPI pull meanwhile adds the new Intel DPTF battery participant driver. This battery participant driver is part of enhancing Intel's Linux support for the Dynamic Platform and Thermal Framework (DPTF).