On Wed, 2013-12-18 at 22:10 +0100, Arnd Bergmann wrote: > On Wednesday 18 December 2013, Sergei Ianovich wrote: > > Could we postpone this until someone needs this functionality? > > We have to be sure that any device tree files you write now can remain > compatible with future kernels if we add it later. My reasoning at first > was that this wouldn't work if we had to change the "compatible" string > for the bus node, but after re-thinking it now I believe that it's fine.
Great. > You would still be able to boot a kernel with an old dts file on a new > kernel if it just contains a "simple-bus" node here, as long as it doesn't > need any boot-time setup at the bus controller. We can change the dts > file later if we need to add this functionality, which would break booting > old kernels with the new dts files, which isn't much of a problem in > general. It should actually only break old kernels which require new functionally. Otherwise, dts can have compatible = "marvell,pxa-extbus", "simple-bus"; and an older kernel will be happy with "simple-bus". Please correct me if I'm wrong. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
