I find the 'STM32MP1_SeriesDDRmemory_routing_guidelines_layout_examples_V3.0' from ST's site.
I've several questions:
Hi @diverger ,
actually, the values in the table are track lengths, so in mm. This values are provided to compensate for package internal track length differences.
Did you have a look to AN5122 ? Excel table is providing also a quick colored check by entering your PCB extracted track length.
I have asked experts to see if they can provide the propagation constant which should be used for the package, but I think the possible time delta versus basic FR4 is probably to be neglected Vs the time delays on your board.
At least many customers using DDR3L have not face issues by following AN5122 or using example routing provided in the ZIP file.