As far as I can tell there are three acpi stacks/interpreters Intel, This is the reference, most operating systems use this (linux, freebsd, macos) Microsoft

As far as I can tell there are three acpi stacks/interpreters Intel, This is the reference, most operating systems use this (linux, freebsd, macos) Microsoft Openbsd, yes the openbsd project is crazy enough to build their own acpi implementation, keep fighting the good fight openbsd. Because have you seen the spec? good lord what a train wreak.