Power Architecture Platform Reference (PAPR) is an initiative from

Power.org Power.org was an organization to develop and promote Power Architecture technology by establishing its open standards, guidelines, best practices, and certifications. Power.org was founded in 2004 by IBM and 15 other companies. Freescale (later ...

to make a new open computing platform based on

Power ISA Power ISA is a reduced instruction set computer (RISC) instruction set architecture (ISA) currently developed by the OpenPOWER Foundation, led by IBM. It was originally developed by IBM and the now-defunct Power.org industry group. Power ISA ...

processors. It follows two previous attempts made in the 1990s,

PReP PowerPC Reference Platform (PReP) was a standard system architecture for PowerPC-based computer systems (as well as a reference implementation) developed at the same time as the PowerPC processor architecture. Published by IBM in 1994, it all ...

and CHRP. The PAPR specification provides the foundation for development of standard server computers. Various operating systems like

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which i ...

and

IBM AIX AIX (Advanced Interactive eXecutive, pronounced , "ay-eye-ex") is a series of proprietary Unix operating systems developed and sold by IBM for several of its computer platforms. Background Originally released for the IBM RT PC RISC w ...

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. In practice, the PAPR is an extension to the

Open Firmware Open Firmware is a standard defining the interfaces of a computer firmware system, formerly endorsed by the Institute of Electrical and Electronics Engineers (IEEE). It originated at Sun Microsystems, where it was known as OpenBoot, and has bee ...

specification. Since 2013, extensions have been done by the

OpenPOWER Foundation The OpenPOWER Foundation is a collaboration around Power ISA-based products initiated by IBM and announced as the "OpenPOWER Consortium" on August 6, 2013. IBM is opening up technology surrounding their Power Architecture offerings, such as proc ...

, which released a slightly reduced public version of the PAPR standard for running Linux on Power hardware (called LoPAPR

In 2020, LoPAPR was renamed to Linux on Power Architecture Reference (LoPAR

with the release of a new version.

Contributing

In July 2020, the document sources of LoPA

were released on terms of Apache License 2.0 in

GitHub account, and are accepting pull requests from the community.

Compliant boards

* IBM JS20/21 — PowerPC 970, PowerPC 970FX/MP based server blades. * The

IBM System p The IBM System p is a high-end line of RISC ( Power)/UNIX-based servers. It was the successor of the RS/6000 line, and predecessor of the IBM Power Systems server series. History The previous RS/6000 line was originally a line of workstations ...

product line, called

IBM Power Systems Power Systems is a family of server computers from IBM that are based on its Power processors. It was created in 2008 as a merger of the System p and System i product lines. History IBM had two distinct POWER- and PowerPC-based hardware l ...

nowadays.

Embedded power architecture platform requirements

Wind River led the Power.org sub-committee working on an embedded specification known as ePAPR''

that was ratified in July 2008. In October 2011, an updated specification was released, the ePAPR v1.1 to clarify and add a new chapter on virtualization. Apart from basic concepts like using a

device tree In computing, a devicetree (also written device tree) is a data structure describing the hardware components of a particular computer so that the operating system's kernel can use and manage those components, including the CPU or CPUs, the memory, ...

, the ePAPR specification has nothing in common with the variant for servers—for example it defines a completely different set of hypercalls.

External links

Sources for LoPAR on OpenPower Foundation Github

OpenPower Foundation Linux on Power Architecture Reference (LoPAR) v2.9+ (Jun 2020)

OpenPower Foundation Linux on Power Architecture Platform Reference (LoPAPR) v1.1 (Mar 2016)

Power.org Standard for Embedded Power Architecture Platform Requirements (ePAPR) v.1.1
at the Wayback Machine.
Power.org
PowerPC mainboards