USB class protocol modules

摘要

A computer system includes USB class protocol-aware modules for USB devices as part of a xHCI host controller. The protocol-aware modules serve as accelerators by implementing critical portions of the device class protocols, which includes fetching higher level protocol data directly from client buffers for transmission and delivering decoded data to client buffers on receipt; and emulating a register-based interface for the benefit of system software on the host computer.

主权项

1. A Universal Serial Bus (USB) class aware protocol module operating with an xHCI controller to transfer data in a memory to a device attached to a USB, the protocol module comprising:
a set of registers and buffers including one or more registers and one or more buffers, the set modeling an interface for transfer of the data over a register oriented bus to the device, the set of registers and buffers receiving commands associated with the transfer of the data to the device; and one or more processors configured to
process the data contained in the set of registers and buffers in accordance with the commands and a USB class protocol corresponding to the device to produce processed data,optimize the processed data for transfer over the USB to the device by the xHCI controller, and in response to an interrupt received over the USB from the device, transfer the processed data over the USB to the device under control of the xHCI controller, wherein access to the registers of the set of registers and buffers does not cause a multiple of transfers over the USB to the device.