PCI express driver interrupt issue

Hi

We're using the Cyclone IV GX transceiver starter kit and we are trying to get the interrupt working in the driver.

We are using MSI interrupts and we try to set up the interrupt with the following line

pci_enable_msi(evio_dev);

As soon as we do this we are unable to use iowrite()'s to write to the hardware using the BARs.

Any input would be greatly appreciated?