I successfully implemented firmware support for resume from S3 sleep on MinPlatform, mentored by Nate DeSimone and Ankit Sinha. It suspends from and resumes to an operating system on my Acer Aspire VN7-572G (Skylake). While presently, the board-specific code is only implemented for KabylakeOpenBoardPkg, I've attempted to ensure that the implementation is as silicon-agnostic as possible. After one last straightforward bug is resolved (involving conditions for detecting the power state), it will be entirely ready for daily use. I performed my testing with Fedora 34, with no relevant modifications.
Although for other platforms, it's expected that more work is required than toggling the S3 feature PCD - and developers may need to prepare for debugging their port of the KabylakeOpenBoardPkg commit - this should be quite straightforward. Therefore, I maintain that the implementation is almost entirely generic across at least all Intel client MinPlatform