OPB_PCI core has errors in the MPD.
C_IPIF2PCI_FIFO_ABUS_WIDTH and C_PCI2IPIF_FIFO_ABUS_WIDTH of opb_pci has the following define, RANGE = (4:14). This is not correct. It should be some conditional range according to the core data sheet, 0 for NO FIFO, (4-12) for Virtex and (4-14) for Virtex-II.
This error prevents running PlatGen when either one is set to 0, which is a valid value.
The work around is to change the MPD file for this define to RANGE = (0:14).
This problem has been fixed in the latest 7.1i EDK Service Pack available at:
The first service pack containing the fix is 7.1i EDK Service Pack 2.