AN APPARATUS AND METHOD FOR COUPLING DEVICES TO A PCI-TO-PCI BRIDGE IN AN INTELLIGENT I/O CONTROLLER

摘要

A controller (202) is coupled to a primary PCI bus (204) and includes a secondary PCI bus (208) coupled to the primary PCI bus (204) by a PCI-to-PCI bridge (206). The secondary PCI bus (208) includes a number of exposed PCI devices that are recognizable by the bridge and a number of hidden PCI devices that are hidden from the bridge. A memory address space is partitioned by the controller (202) and assigned to each of the hidden PCI devices. The hidden PCI devices use the memory address space to transmit data to a local CPU (214). The controller (202) also includes a local-to-PCI bridge (210) coupled to the secondary PCI bus (208) and a local bus including a memory (216) and a processor. The local-to-PCI bridge (210) acquires a second memory address space that is part of the system memory used for transmission between hidden PCI devices and local memory.