OpenPOWER Foundation specifications are publicly available, royalty-free standards that define the POWER architecture ecosystem — from the instruction set through platform interfaces.
The POWER ISA is the foundational specification for all OpenPOWER-compliant processors. It is maintained by the OpenPOWER Foundation and published as an open standard.
| Specification | Version | Status | Description | Download |
|---|---|---|---|---|
| POWER ISA | v3.1C | Current | Latest POWER Instruction Set Architecture specification including Matrix Math Assist (MMA) and all current extensions | PDF ↗ |
| POWER ISA | v3.1B | Stable | POWER ISA specification including all extensions | PDF ↗ |
| POWER ISA | v3.0C | Stable | Previous major version of the POWER ISA | PDF ↗ |
| POWER ISA | v2.07B | Stable | Earlier ISA specification | PDF ↗ |
Platform specifications define the system-level interfaces that ensure interoperability across OpenPOWER-compliant hardware and software.
| Specification | Version | Status | Description | Link |
|---|---|---|---|---|
| OpenPOWER Platform Requirements | v2.0 | Current | Defines minimum hardware requirements for OpenPOWER-compliant server platforms | View ↗ |
| OPAL (OpenPOWER Abstraction Layer) | Current | Current | Firmware API between hypervisor/OS and platform firmware (Skiboot) | Docs ↗ |
| OpenCAPI Interface Specification | v4.0 | Stable | High-speed, low-latency coherent interface between processors and accelerators | View ↗ |
| ELFv2 ABI Specification | v1.5 | Current | 64-bit PowerPC ELF Application Binary Interface — defines calling conventions and binary format | PDF ↗ |
| Linux on Power Architecture | Current | Current | Guidelines and requirements for Linux distributions on OpenPOWER platforms | View ↗ |
All 13 technical specifications published by the OpenPOWER Foundation, covering the ISA, hardware interfaces, ABI, and software references.
| Specification | Status | Description | Link |
|---|---|---|---|
| 64-bit ELF ABI Specification | Current | 64-bit PowerPC ELF Application Binary Interface — defines calling conventions, data types, and binary format for POWER | View ↗ |
| Advanced Accelerator Adapter Electro-Mechanical Specification | Current | Electro-mechanical requirements for advanced accelerator adapter cards in OpenPOWER systems | View ↗ |
| Coherent Accelerator Interface Architecture (CAIA) | Current | Defines the CAPI interface for coherent, low-latency communication between the POWER processor and attached accelerators | View ↗ |
| Field Replaceable Unit Service Interface (FSI) | Current | Specification for the FSI bus used to access service functions on POWER systems and attached devices | View ↗ |
| Instruction Set Architecture (ISA) | Current | The foundational POWER Instruction Set Architecture specification — open, royalty-free, and maintained by the OpenPOWER Foundation | View ↗ |
| IO Design Architecture (IODA) Specification | Current | Architecture definition for I/O subsystem design on OpenPOWER platforms, including interrupt and DMA handling | View ↗ |
| Linux on POWER Architecture Reference | Current | Reference guide for Linux on POWER architecture — covering platform requirements and boot interfaces for Linux distributions | View ↗ |
| Memory Bus Specification | Current | Specification for the memory bus interface used in OpenPOWER-compliant server platforms | View ↗ |
| OpenCAPI POWER Platform Architecture Guide | Current | Platform architecture guide for integrating OpenCAPI high-speed coherent accelerator interfaces on POWER systems | View ↗ |
| PowerVM on POWER Architecture Reference (PAPR) | Current | Architecture reference for the POWER Architecture Platform Requirements used by PowerVM and Linux guests | View ↗ |
| PSL / AFU Interface Specification | Current | Defines the interface between the CAPI PSL (Power Service Layer) and AFU (Accelerator Function Unit) for CAPI-attached accelerators | View ↗ |
| Vector Intrinsics Porting Guide | Current | Guide for porting applications using vector intrinsics to the POWER architecture's AltiVec/VMX and VSX extensions | View ↗ |
| Vector Intrinsics Programming Reference | Current | Complete programming reference for POWER vector intrinsics — VMX, VSX, and MMA instruction mappings for C/C++ developers | View ↗ |
OpenPOWER specifications are developed collaboratively by Foundation members. Join a Working Group to participate in shaping the future of open computing standards.
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