US Patent 7676625 Cross-coupled peripheral component interconnect express switch

A plurality of PCIe switch complexes are interposed between a plurality of I/O devices and a plurality of microprocessor complexes. Each PCIe switching complex comprises a plurality of PCIe switches wherein each switch possesses at least one non-transparent port. The non-transparent port is used to cross-couple each PCIe switch creating an active matrix of paths between the HBAs associated with each I/O device and each microprocessor. The paths between each HBA (I/O device) and each microprocessor are mapped using a recursive algorithm providing each I/O device with direct memory access to each microprocessor.