On 04-12-19, 10:33, Thierry Reding wrote: > Yeah, the code that registers this device is in drivers/base/cpu.c in > register_cpu(). It even retrieves the device tree node for the CPU from > device tree and stores it in cpu->dev.of_node, so we should be able to > just pass &cpu->dev to tegra_bpmp_get() in order to retrieve a reference > to the BPMP. > > That said, I'm wondering if perhaps we could just add a compatible > string to the /cpus node for cases like this where we don't have an > actual device representing the CPU complex. There are a number of CPU > frequency drivers that register dummy devices just so that they have > something to bind a driver to. > > If we allow the /cpus node to represent the CPU complex (if no other > "device" does that yet), we can add a compatible string and have the > cpufreq driver match on that. > > Of course this would be slightly difficult to retrofit into existing > drivers because they'd need to remain backwards compatible with existing > device trees. But it would allow future drivers to do this a little more > elegantly. For some SoCs this may not matter, but especially once you > start depending on additional resources this would come in handy. > > Adding Rob and the device tree mailing list for feedback on this idea. Took some time to find this thread, but something around this was suggested by Rafael earlier. https://lore.kernel.org/lkml/8139001.Q4eV8YG1Il@xxxxxxxxxxxxxx/ -- viresh