Phoronix reports that Lenovo and AMD engineers have just teamed up to create an “Automatic Mode Transition” (AMT) patch for the Linux 6.0 kernel. However, as a set of options to help systems automatically adjust power performance modes, it initially seems to be available only on select ThinkPad laptops (augmented by the ThinkPad ACPI kernel driver).
Phoronix notes that AMD Auto Mode Switching can be seen as a derivative of “firmware-based dynamic power performance tuning,” which is associated with ACPI platform profile support.
In the preset “Balanced Mode”, supported ThinkPad / AMD laptops running the Linux 6.0+ kernel can allow AMT to dynamically adjust the profile parameters on a specific platform based on firmware driver decisions.
In addition, on some AMD platforms, the Fn+T key combination can also be used to activate/deactivate AMT functionality. In a Linux 6.0+ ThinkPad environment, for example, users can query the printout to dmesg to determine AMT status.
Coincidentally, just last week Michael Larabel tested and shared some benchmark results of the ACPI platform profile mode on a ThinkPad X13 Gen 3 model with AMD Raider PRO 7 6850U processor.
It is clear that in profile mode, the machine is able to squeeze out some minor performance/heat dissipation benefits. And in low-power mode, the system visitors further improved performance per watt.
It should be noted that while the initial AMD AMT integration in Linux 6.0 is only available for Lenovo products with the ThinkPad ACPI driver. However, it is expected that the feature will soon be rolled out to models from more vendors as well.
Earlier, AMD started pushing out the Platform Management Framework (PMF) driver. It enables a more comprehensive “cross-vendor” experience than AMT, and debuts support for AMD Rembrandt SoCs.
Interestingly, AMD PMF is somewhat similar to Intel’s Dynamic Platform and Thermal Framework (DPTF) — after all, it is also a centralized set of sensors, prompts, platform status and hardware metrics designed to dynamically tune system performance/power consumption performance.
Finally, AMD AMT support for ThinkPad has been committed to the Linux 6.0 merge window as part of the platform-drivers-x86 update.
The maintainers also brought additional support and improvements for Microsoft Surface laptops, microphone mute LED handling in the ASUS WMI driver, Intel P2SB updates, and many other small changes that benefit Linux laptops.
