Linux 5.10 To Fix Some HP Laptops Performing Less Than Optimally On AC Power

Some HP Spectre laptops and possibly other HP models as well should be performing better when running on AC power starting with the Linux 5.10 kernel.

With at least some HP Spectre laptops, the firmware has been setting the thermal policy to the default but hard-coding an Intel DPTF (Dynamic Platform and Thermal Framework) variable that was leading to thermald choosing the wrong DPTF profile and in turn leading to lower performance on AC power where as normally the highest performance is achievable when running on AC power rather than battery.

But come Linux 5.10 there will be thermal policy support for HP-WMI. The HP WMI driver will now honor the desired thermal policy and also call the necessary write command to ensure the DPTF setup gets configured properly. The four thermal policies supported by newer HP notebooks include HP Recommended, Performance, Cool, and Quiet.

This HP thermal policy work is already related to the recent push for a new knob/sysfs for toggling performance/power-profiles on laptops under Linux. That new interface isn't queued for introduction with Linux 5.10 but will hopefully see the mainline kernel in 2021.