Various operating systems like Linux and IBM AIX rely on the PAPR interface to run on Power-based hardware.
PAPR is Power.org's move toward what IBM did originally with PReP, in that it defines a common hardware definition and software/firmware platform under a set of requirements.
Since 2013, extensions have been done by the OpenPOWER Foundation, which released a slightly reduced public version of the PAPR standard for running Linux on Power hardware (called LoPAPR) [1].
In July 2020, the document sources of LoPAR [3] were released on terms of Apache License 2.0 in OpenPOWER Foundation GitHub account, and are accepting pull requests from the community.
Apart from basic concepts like using a device tree, the ePAPR specification has nothing in common with the variant for servers—for example it defines a completely different set of hypercalls.