Emulex Design & Manufacturing Corporation

Emulex Corporation

Daming Jin

Vuong Cao Nguyen

John Sui-kei Tang

Peter Mark Fiacco

Jim Donald Butler

Joe Chung-Ping Tien

Sam Shan-Jan Su

David James Duckman

Eddie Miller

Michael P Yan

Restoring retired transaction identifiers (TID) associated with Direct Memory Access (DMA) commands without waiting for all DMA traffic to terminate is disclosed. A scoreboard is used to track retired TIDs and selectively restore retired TIDs on the fly. DMA engines fetch a TID, and use it to tag every DMA request. If the request is completed, the TID can be recycled to be used to tag a subsequent request. However, if a request is not completed, the TID is retired. Retired TIDs can be restored without having to wait for DMA traffic to end. Any retired TID value may be mapped to a bit location inside a scoreboard. All processors in the system may have access to read and clear the scoreboard. Clearing the TID scoreboard may trigger a DMA engine to restore the TID mapped to that location, and the TID may be used again.

Restore PCIe transaction ID on the fly

This is directed to methods and systems for handling access requests from a device to a host. The device may be a device that is part of the host, such as an HBA, an NIC, etc. The device may include a processor which runs firmware and which may generate various host access requests. The host access requests may be, for example, memory access requests, or DMA requests. The device may include a module for executing the host access requests, such as a data transfer block (DXB). The DXB may process incoming host access requests and return notifications of completion to the processor. For various reasons, the processor may from time to time issue null or zero length requests. Embodiments of the present invention ensure that the notifications of completion for all requests, including the zero length requests, are sent to the processor in the same order as the requests.

Efficient processing of groups of host access requests that may include zero length requests

A hardware-based offload engine is disclosed for mapping protected data into frames. For a write operation, the HBA determines host addresses and the size of data to be read from those addresses. The HBA also determines the frame size and protection scheme for data to be written. A frame transmit engine reads each host descriptor in the host data descriptor list to determine the location and byte count of the data to be read. A DMA engine reads the protection information/scratch area to determine the exact data size used to fill each frame and the protection scheme, and retrieves one or more free frame buffers. Check bytes are inserted alongside the data and stored in free frame buffers. After each frame is filled, the frame transmit engine also generates and stores header information for that frame, and then combines header, data and check bytes for transmission over the network.

Autonomous mapping of protected data streams to fibre channel frames

A method and system for allowing a host device (e.g., server) to perform programmed direct accesses to peripheral memory (e.g., flash) located on a peripheral device (e.g., HBA), without the assistance of a microprocessor located on the peripheral device. In a preferred embodiment, new host registers are implemented within controller circuitry of the peripheral device, the host registers being configured to be recognized by host software executed by host. The host device reads and writes to the host registers, which causes appropriate controller hardware to access the peripheral nonvolatile memory accordingly. By creating and implementing the new host registers, an enhanced controller is created that allows a host device to directly access peripheral memory, without peripheral processor assistance.

System and method for direct memory access from host without processor intervention wherein automatic access to memory during host start up does not occur

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Costa Mesa, CA, United States of America

Daming Jin