An increasing amount of x86 and ARM64 hardware is expected in the marketplace soon that supports CPPC, which is a new interface for CPU performance control between the OS and platform, while right now it's just exposed by a limited number of systems. Here's more from Ashwin's description:
CPPC is the new interface for CPU performance control between the OS and the platform defined in ACPI 5.0+. The interface is built on an abstract representation of CPU performance rather than raw frequency. Basic operation consists of:
* Platform enumerates supported performance range to OS
* OS requests desired performance level over some time window along with min and max instantaneous limits
* Platform is free to optimize power/performance within bounds provided by OS
* Platform provides telemetry back to OS on delivered performance
The Collaborative Processor Performance Control work published is largely just a starting point and to initiate discussion about implementing this CPU performance-controlling feature. Those interested in learning much more can read this lengthy email post.