A configurable bus is one that can be configured in software. Devices on these buses must have Plug and Play WDM device drivers. The PCI bus driver will retrieve a device's details and generate an appropriate Hardware ID. This Hardware ID will be used to identify the correct driver. Its AddDevice routine is called, etc.

In NT systems, you will need to use a different technique to get configurable bus data. This method still works in Windows 2000. The HalGetBusData and HalGetBusDataByOffset calls can be made to retrieve configuration data for one slot of a specified bus instance. For example, if you ask for PCIConfiguration bus data, the passed buffer is filled with PCI_COMMON_CONFIG data.

You can then claim the necessary resources using IoAssignResources, in a similar way to IoReportResourceUsage. As an alternative, drivers of PCI-type devices can call HalAssignSlotResources. HalSetBusData and HalSetBusDataByOffset can be used to write back configuration data.

I have not tried it, but it looks as though HalGetBusData and HalSetBusData can be used to access the BIOS CMOS data.