Methods and structure for communicating between a SATA host and a SATA target device through a SAS domain

摘要

Methods and structure for directly coupling SATA hosts (SATA initiators) with SATA target devices through a SAS fabric and an enhanced SAS expander supporting such direct couplings. The enhanced SAS expander comprises SATA/STP connection logic to open a SAS (STP) connection between a directly attached SATA host and a SATA target device in response to receipt of an FIS from the host or target while no connection is presently open. The opened connection is closed after expiration of a predetermined timeout period of inactivity between the connected host and target. Thus, simpler, less costly SATA hosts and SATA target devices may be utilized while gaining the advantage of SAS architecture flexibility in configuration and scalability. SATA hosts may be coupled through the SAS fabric with a larger number of SATA target devices and multiple SATA hosts may be coupled with the SAS fabric.

主权项

1. An enhanced Serial Attached SCSI (SAS) expander comprising:
a first physical link (PHY) for coupling the SAS expander with a Serial Advanced Technology Attachment (SATA) host, wherein the SATA host exchanges information with the expander using SATA protocol, wherein the PHY receives a first Frame Information Structure (FIS) from the SATA host, the FIS being directed to a SATA target device; and a SATA Tunneling Protocol (STP) connection circuit operable to open and close an STP connection between the SATA host and the SATA target device through the expander in response to receipt of the first FIS, wherein SATA protocol logic of the STP connection circuit holds transfer of the FIS via SATA HOLD primitives until the STP connection circuit establishes STP acceptance with the SATA target device.