On Tue, Feb 28, 2017 at 9:14 AM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: > [...] > >>> ---> Parent domain-2 (Contains Perfomance states) >>> | >>> | >>> C.) DeviceX ---> Parent-domain-1 | >>> | >>> | >>> ---> Parent domain-3 (Contains Perfomance states) >> >> I'm a bit confused. How does a domain have 2 parent domains? > > This comes from the early design of the generic PM domain, thus I > assume we have some HW with such complex PM topology. However, I don't > know if it is actually being used. > > Moreover, the corresponding DT bindings for "power-domains" parents, > can easily be extended to cover more than one parent. See more in > Documentation/devicetree/bindings/power/power_domain.txt I could easily see device having 2 power domains. For example a cpu may have separate domains for RAM/caches and logic. And nesting of power domains is certainly common, but a power domain being contained in 2 different parents? I don't even see how that is possible in the physical design. Now if we're mixing PM and power domains again and the cpu device is pointing to the cpu PM domain which contains 2 power domains, then certainly that is possible. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
