PCI device development (newbie question)

Hello, ddd-group.

Newly developed device might not work initially, therefore
any driver is of little help. Am I right?

I have a PCI device which I plan to connect to PC via
standard bridge (this is Intel's 21152, working, drivers OK)

Please advice how to access my device for debug purposes, without custom
driver. Where to start, what to look at?
Sure there will be protocol, parity errors, irresponsive addresses etc.

I have Windows XP pro, MS Deloper's studio 2003.

TIA