I have an interface board with an XIO2001 bridge acting as a transparent bridge in front of a PowerPC device (endpoint). The XIO2001 is set to use the default values such that the subvendor and subsystem IDs are both 0x0000. The PowerPC is set up by our firmware with the Subvendor and subsystem IDs to non-zero values which identify our board. We are seeing an issue in a Dell T110-II system where, during bus enumeration, the non-zero values of the subvendor and subsystem IDs in the PowerPC device are being copied to the Subvendor and subsystem ID registers in the XIO2001, and the PowerPC subvendor and subsystem ID registers are being written with Dell-specific values.
Is there any way that the XIO2001 device that could be contributing to this issue?