Importance

Loading Importance Indicators...

Abstract

The present invention is directed to a method and apparatus of automatic power management control for a Serial ATA device directly attached to a SAS/SATA host controller. In an exemplary aspect of the present invention, it is determined whether a Serial ATA device is directly attached to a SAS/SATA host controller without using a SAS expander. When it is determined that the Serial ATA device is directly attached to the SAS/SATA host controller, an idle or active condition of a Serial ATA interface including the Serial ATA device and the SAS/SATA host controller is automatically detected. When the Serial ATA interface is in an idle condition, idle time of the Serial ATA interface is measured using a power down counter whose frequency is determined by a programmable register based on an input clock. When a power down counter value is equal to a first value, a request for a Partial power state is asserted, and Serial ATA interface is put into a Partial power state. When a power down counter value is equal to a second value, a request for a Slumber power state is asserted, and Serial ATA interface is put into a Slumber power state.

Loading the Abstract Image...

First Claim