Michael Ellerman <mpe@xxxxxxxxxxxxxx> writes: > "Rob Herring (Arm)" <robh@xxxxxxxxxx> writes: >> While OpenFirmware originally allowed walking parent nodes and default >> root values for #address-cells and #size-cells, FDT has long required >> explicit values. It's been a warning in dtc for the root node since the >> beginning (2005) and for any parent node since 2007. Of course, not all >> FDT uses dtc, but that should be the majority by far. The various >> extracted OF devicetrees I have dating back to the 1990s (various >> PowerMac, OLPC, PASemi Nemo) all have explicit root node properties. > > I have various old device trees that have been given to me over the > years, and as far as I can tell they all have these properties (some of > them are partial trees so it's hard to be 100% sure). > > So LGTM. Turns out I was wrong. The warning about #size-cells hits on some powermacs, possible fixup patch here: https://lore.kernel.org/linuxppc-dev/20241126025710.591683-1-mpe@xxxxxxxxxxxxxx/ cheers