"AMD’s Ryzen 9 3900X also has the new Collaborative Power Performance Control 2 (CPPC2) feature, which manipulates Ryzen 3000's power states from within the operating system. This is similar to Intel's Speed Shift technology and reduces power state transition latency. Ultimately, that results in a more efficient processor during all facets of operation."

Though that seems to be about boosting clocks higher clocks when it can.

https://www.amd.com/en/technologies/smartshift

Again does seem to focus upon boosting performance

So no clear-cut stand-out answer, but does seem some level of OS interaction is required, I couldn't say with 100% certainty.