1、ACPI Overview,Contents,Power Management History ACPI ACPI States and Software Components ACPI History Changing ACPI,Power Management History,Advanced Power Management (APM) BIOS-based system power management Provides CPU and device power management Called when idle - provides CPU power mgt. Uses dev
2、ice activity timeouts to determine when to transition devices into low power states OS has no knowledge of what APM does Each IBV must refine and maintain APM BIOS code/IP Wide variety of implementations and functionality No uniform user experience,ACPI,Advanced Configuration and Power Interface Con
3、ceived by Intel, Microsoft, and Toshiba (the promoters) An “interface” specification ACPI/OSPM replaces APM, MPS, and PnP BIOS Spec Allow OS-directed Power Management (OSPM) Defines Hardware registers - implemented in chipset silicon BIOS interfaces Configuration tables Interpreted executable functi
4、on interface (Control Methods) Motherboard device enumeration and configuration System and device power states ACPI Thermal Model,ACPI Global States and Transitions,An ACPI System,ACPI Software Components,ACPI Subsystem Consumes ACPI BIOS Interacts with ACPI Hardware Policy Manager (OSPM) Sets and M
5、onitors System Policies User Interface Allows User Input to Policy Device Drivers EC, SM Bus, CM Battery, Smart Battery,ACPI System Overview,ACPI Specification History,ACPI 1.0 released December 1996 ACPI 1.0a released July 1998 ACPI 1.0b released February 1999ACPI 2.0 released July 2000,How does ACPI change?,Periodic errata meetings held with promotersEither spec is updated (e.g. 1.0a, 1.0B, etc) or an errata document is posted on the ACPI site: http:/www.acpi.info,
