Technical Q&A

HW64 - Are the Name Registry device tree nodes unique? (11-October-1999)

Q: Are the Name Registry device tree nodes unique?

A: No, the unit addresses from the Open Firmware device tree were not copied to the Name Registry. This means that there may be more than one node with the same name. For instance using a B&W G3, the PCI bridge node as viewed with the "Display Name Registry" utility has a name called "/pci". When viewed using the Open Firmware user interface the same node is displayed as /pci@80000000. The name "pci" is generic per the Recommended Practices for IEEE 1275. When searching the Name Registry for a string, remember to first determine how many PCI nodes there are in the device tree. Your search algorithm can then search each node until the individual searches are complete.