This repository will contain all documentation for the OpenPower open source software that's being released to support the POWER ecosystem.
As always is the case with documentation, it usually needs some updates. So feel free to do it yourself :) or touch base with us on the mailing lists.
It is recommended that you first read the Hostboot Programmers Guide and the OCC Overview. These documents will give you an overview of the OCC, Hostboot firmware and some pointers on the source code.
Details on POWER8 and POWER9 hardware designs can be found at the IBM Portal for OpenPOWER.