AMD Developing "PMF" Linux Driver For Better Desktop/Laptop User Experience

AMD recently started posting Linux patches for a Platform Management Framework "PMF" driver that is designed to "enhance end user experience by making AMD PCs smarter, quieter, power efficient by adapting to user behavior and environment."

The AMD PMF Linux driver aims to make for a better client user experience for AMD PCs and laptops running Linux. At least at a high level it sounds similar to what Intel already does for their hardware on Linux with their various thermal/power kernel drivers paired with their Thermald user-space daemon in user-space for supporting their Dynamic Platform and Thermal Framework (DPTF).

The new driver is described by AMD engineer Shyam Sundar S K as:

AMD PMF Driver (a.k.a Platform Management Framework) provides a centralized framework based on sensor inputs, OS hints, platform state and APU metrics to dynamically manage perf, power and system thermals.

The goal of the driver is to enhance end user experience by making AMD PCs smarter, quieter, power efficient by adapting to user behavior and environment.

The larger goals include:

- Enable easy customization of smart PC solutions by OEMs.
- Provide a framework for OEMs to add in custom algorithms and solutions
- Improve standby and dynamic platform power through active power management of platform devices.

In this series, support for following features has been added.
- "Static Power Slider" meant to manage the power budget based on the power modes or the slider position.
- "Auto Mode" tracks the moving power average of the APU and takes intelligent decisions to switch between different modes.

There already is some existing bits like ACPI Platform Profile support as a standard that is handled already by some laptop vendors with AMD Ryzen SoCs on Linux. AMD's PMF appears to take things further similar to Intel's thermal/power DPTF management handling on Linux as a more wholesome solution for their hardware platforms. AMD PMF should allow for better thermal/power control over the system, allowing Linux users easier access over fan control, etc.

This driver interacts with the AMD power management firmware of the system. At least initially the target support is for hardware with an "AMDI0102" ACPI ID and is introduced with the recent Ryzen 6000 "Rembrandt" mobile SoCs. Presumably AMD PMF will be supported by all future client platforms, including desktop APUs. On the Windows side it appears they have been working on PMF support in their chipset driver since earlier in the year.

From my AMD Ryzen 7 PRO 6850U Linux benchmarks with the ThinkPad X13 Gen 3, the Ryzen 6000 "Rembrandt" laptops are working nice on Linux already while the PMF support has the potential for power/thermal enhancements.

Over the past year AMD has been hiring more on the client side for Linux improvements. AMD has also experienced Linux client successes such as with the Tesla in-vehicle infotainment system, Valve's Steam Deck, and more Linux laptop pre-loads. AMD PMF should help well in these efforts for future generations bearing PMF.

At the moment the 1.4k lines of new kernel code wiring up the AMD PMF driver is under review on the kernel mailing list and has undergone a few rounds of review the past few days. If all goes well the AMD Platform Management Framework driver could be merged for Linux 6.1 later this year.