Selectively coupling a PCI host bridge to multiple PCI communication paths

摘要

Instead of disabling PCI communication between system resources in a host computing device and I/O devices when a PCI Host Bridge (PHB) is reset, the host computing device may include a PCI communication path for maintaining communication between the system resources and the I/O devices. In one embodiment, the redundant PCI communication path includes a second PHB that is maintained in a standby state. The host may monitor the errors generated by a plurality of master PHBs and select a master PHB that satisfies an error threshold. The second PHB (i.e., a servant PHB) and the selected master PHB are synchronized, and the second PHB is coupled to the PCI communication path between the master PHB and a PCI switch. The master PHB can then be reset while the second PHB maintains PCI communication between the host and the I/O devices.

主权项

1. A computing system, comprising:
a plurality of master peripheral component interconnect (PCI) host bridges, each master PCI host bridge (PHB) is coupled to a respective PCI switch via a respective PCI communication path for facilitating PCI communication between the computing system and I/O devices; a servant PHB selectively coupled to each of the PCI communication paths via selection logic; and supervisory logic configured to:
upon determining that one of the plurality of master PHBs satisfies an error threshold, assign the servant PHB to backup the one master PHB;upon assigning the servant PHB to backup the one master PHB, synchronize the servant PHB with the one master PHB;couple, using the selection logic, the servant PHB to the respective PCI communication path of the one master PHB; andreset the one master PHB, wherein PCI communication between the computing system and at least one of the I/O devices flows through the servant PHB while the one master PHB is reset.