PCI-E natively provides a legacy interrupt mode which in turn
simulates PCI interrupt lines. This provides support for operating
systems which do not yet have support for the enhanced space. This
also allows us to change drivers over in an incremental fashion
because the drivers can choose whether to use MSI or the legacy
interrupt mode. I'm not currently very familiar with our PCI code. So
I'm not aware of the resources required for supporting PCI-E and MSI.
Though most likely all of this code will need to be completely
re-written.
--
-David
Steven David Rhodus
<drhodus@machdep.com>