Is DVFS Worth The Effort
By: Brian Bailey
Dynamic voltage and frequency scaling can save a lot of power and energy, but design costs can be high and verification difficult.
Along with the additional design complexity, verification complexity, and software issues, there are other things that the team needs to keep in mind. “When considering the overall cost and benefit of DVFS, you need to consider security,” says Sergio Marchese, technical marketing manager for OneSpin Solutions. “Remote physical attacks based on triggering faults through circuit misuse are on the rise. Rowhammer is a well-known example. DVFS features also can be leveraged to provoke glitches and target faults. Depending on the application, it may be necessary to do a risk assessment, identify weaknesses, and introduce security measures that prevent malicious misuse. No pushbutton tools exist that address this security assurance challenge. Formal tools have the capacity and features to combine an exhaustive analysis of complex DVFS control functions with fault injection, which can identify issues and validate mitigation strategies.”
Perhaps the biggest impediment to adoption is that dynamic systems rely on re-architecting of software, and that places additional cost and risk on a project. Over time, the power savings may force that to change.