ACPI

For others, see ACPI (disambiguation).
Advanced Configuration and Power Interface
AbbreviationACPI
StatusPublished
First publishedDecember 1996
Latest version6.5
August 2022
Organization
Related standardsUEFI
Predecessor
DomainPower management firmware
Websiteuefi.org/acpi

Advanced Configuration and Power Interface (ACPI) is an open standard that operating systems can use to discover and configure computer hardware components, to perform power management (e.g. putting unused hardware components to sleep), auto configuration (e.g. Plug and Play and hot swapping), and status monitoring. It was first released in December 1996. ACPI aims to replace Advanced Power Management (APM), the MultiProcessor Specification, and the Plug and Play BIOS (PnP) Specification.[1] ACPI brings power management under the control of the operating system, as opposed to the previous BIOS-centric system that relied on platform-specific firmware to determine power management and configuration policies.[2] The specification is central to the Operating System-directed configuration and Power Management (OSPM) system. ACPI defines hardware abstraction interfaces between the device's firmware (e.g. BIOS, UEFI), the computer hardware components, and the operating systems.[3][4]

Internally, ACPI advertises the available components and their functions to the operating system kernel using instruction lists ("methods") provided through the system firmware (UEFI or BIOS), which the kernel parses. ACPI then executes the desired operations written in ACPI Machine Language (such as the initialization of hardware components) using an embedded minimal virtual machine.

Intel, Microsoft and Toshiba originally developed the standard, while HP, Huawei and Phoenix also participated later. In October 2013, ACPI Special Interest Group (ACPI SIG), the original developers of the ACPI standard, agreed to transfer all assets to the UEFI Forum, in which all future development will take place.[5] The latest version of the standard 6.5 was released in August 2022.[6]

  1. ^ "ACPI Overview" (PDF). www.acpi.info. Archived from the original (slide show in PDF) on May 25, 2019.
  2. ^ "APM BIOS Specification". Intel Corporation, Microsoft Corporation. February 1996. Archived from the original (RTF) on February 6, 2012. Retrieved July 2, 2010.
  3. ^ "What is ACPI (Advanced Configuration and Power Interface)? - Definition from WhatIs.com". SearchWindowsServer. Retrieved September 18, 2020.
  4. ^ "ACPI Device Tree - Representation of ACPI Namespace — The Linux Kernel documentation". www.kernel.org. Retrieved September 18, 2020.
  5. ^ "The Advanced Configuration & Power Interface web page has a prominent note that links to the Preexisting ACPI Specifications page on the UEFI web site". acpi.org. July 23, 2014. Archived from the original on June 22, 2011. Retrieved January 25, 2016.
  6. ^ "Advanced Configuration and Power Interface Specification, Release 6.5" (PDF). UEFI.org/specifications. August 2022. Retrieved October 4, 2022.