Patent ID: 8266331

Claim:
A method comprising: at a first computing device coupled to a second computing device via a bus, receiving a request from the second computing device to complete a non-posted command, wherein the request is received via a request credit channel of the bus, and wherein the first computing device is configured to receive requests to complete non-posted commands and requests to complete posted commands via the request credit channel, and wherein each non-posted command is a memory read command, a memory read lock command, an input/output (I/O) read command, an I/O write command, a configuration read command, or a configuration write command, and wherein each posted command is a memory write command or a messaging command; removing the request to complete the non-posted command from the request credit channel; transmitting a retry request prompting a reissue of the request to complete the non-posted command to the second computing device via a response credit channel of the bus, wherein the retry request includes a retry bit in an enabled state, and wherein the retry bit in the enabled state enables the second computing device to recognize the retry request; and after transmitting the retry request via the response credit channel, receiving a second request to complete the non-posted command via the request credit channel based on the retry bit in the retry request in the enabled state, wherein the request credit channel of the bus transmits requests to complete commands from the second computing device to the first computing device, and the response credit channel transmits retry requests prompting reissues of requests to complete commands from the first computing device to the second computing device.