Could AMD give a definitive answer on what power settings can/could be set on mobile APUs?
By power setting, I mean the voltage and frequency of the p-states, and the power limits (STAPM). Is it possible to undervolt these cpu even though no software is offered to do it yet?
Besides, can anyone confirm that MWAIT instruction and SMT must be avoided due to a silicon error?
- Power limit lifting through modification of the bios or ACPI tables (DSDT): https://www.reddit.com/r/Amd/comments/a2vs55/i_successfully_disabled_stapm_and_increased_the/
- p-state configuration: GitHub - r4m0n/ZenStates-Linux: Dynamically edit AMD Ryzen processor P-States or GitHub - sjug/go-zenstates: Golang tool to modify Ryzen CPU p-state settings from Linux CLI
- p-state not editable on linux?: zenstates.py fails when msr module is built into kernel · Issue #5 · r4m0n/ZenStates-Linux · GitHub
- Errata from AMD, not sure if second gen Ryzen CPUs is concerned, can't understand the technical jargon: Ryzen product errata published : Amd
- discussion about above bug: https://community.amd.com/message/2895178?commentID=2895178#comment-2895178
- Linux bug: https://bugzilla.kernel.org/show_bug.cgi?id=196683