Multiple device bridge apparatus and method thereof

A method of accessing a plurality of processing devices, the method comprising the steps of:

• asserting a set of primary nodes to provide access to a first processing device, wherein the primary nodes are associated with a point-to-point bus protocol;
• asserting a first set of auxiliary control nodes and a portion of the primary nodes to provide access to a second processing device;
• and
• asserting a second set of auxiliary control nodes and a portion of the primary nodes to provide access to a third processing device such that graphics data may be transferred between the first processing device at least one of:
• the second processing device and the third processing device.

An apparatus for providing bus access for multiple processing devices, the apparatus comprising:

• a first bus portion based on a point-to-point bus protocol to be coupled to a first processing device, and a subset of the first bus portion to be coupled to a second processing device and a third processing device;
• a second bus portion used to extend the point-to-point protocol to support additional masters to be coupled to the second processing device and the third processing device;
• and
• a multi-device channel controller disposed between the first bus portion and the second bus portion, wherein the multi-device channel controller includes:
• a first control device having a bus interface port coupled to the first bus portion and the second bus portion;
• a second control device coupled to the second processing device;
• and
• a third control device coupled to the third processing device such that graphics data may be transferred between the first processing device and at least one of:
• the second processing device and the third processing device.