Patent ID: 7752375
Filing Date: 2010-07-06
Classification: G06F

Abstract:
1. An input output control device controlling a plurality of interfaces transmitting and receiving data in units of frames, the input output control device comprising: a plurality of ports each having interface control circuits controlling said interfaces independently with each other port; a common received data buffer, being divided into a plurality of entries, storing frame data received by said plurality of ports; a common transmitted data buffer, being divided into a plurality of entries, storing the frame data to be transmitted to said plurality of ports; and a single protocol processing circuit, to process collectively a plurality of protocols executed on said plurality of interfaces, carrying out processing of the frame data in said common transmitted data buffer and said common received data buffer, wherein each interface control circuit comprises: a register defining a number of common received data buffer entries that can be used by a concerned port for a number of buffer credits within a range of the total number of common received data buffer entries; wherein said input output control device further comprises: a reception buffer control circuit storing, to said common received data buffer, the frame data received by said plurality of ports, wherein said reception buffer control circuit comprises: a received data stack which, after said reception buffer control circuit has stored frame data from one of said plurality of ports to said common received data buffer, stores Dort number of the concerned Dort and buffer entry number of said common received data buffer storing said frame data; and wherein said reception buffer control circuit comprises: a reception port number register sequentially reading out and storing the contents of said received data stack, as well as a reception buffer entry number register, and, when said protocol processing circuit receives a processing request from said reception buffer control circuit, reads out the contents of said reception Dort number register and said reception buffer entry number register and performs protocol processing.