On Tue, Jul 30, 2013 at 11:50:31AM +1000, David Gibson wrote: > On Mon, Jul 29, 2013 at 01:23:39PM -0400, Jason Cooper wrote: > > On Mon, Jul 29, 2013 at 05:49:05PM +0100, Dave Martin wrote: > > > On Mon, Jul 29, 2013 at 11:01:24AM -0400, Jason Cooper wrote: > > > > On Mon, Jul 29, 2013 at 02:21:52AM +0200, Tomasz Figa wrote: > > > > > > > b) What information should be specified in schemas? What level of > > > > > granularity is required? > > > > > > > > One item I don't see in this list is node ordering. There's been some > > > > discussion lately on deferred probing (re boot times). If we were to > > > > intentionally declare that DT are parsed in the order written, then a > > > > lot of deferred probes could be avoided by moving eg the pinctrl node to > > > > near the top of the tree. > > > > > > > > This doesn't impact buses as much, since the nodes needing the bus are > > > > already children. However, anything accessed via phandles: pins, > > > > clocks, regulators, etc could benefit from declaring and enforcing this. > > > > Eg having the dtc warn when a phandle is used before it's corresponding > > > > node is declared. > > > > > > > > Not critical though, just a thought. > > > > > > I don't think that siblings have any defined order in DT. If reading a > > > device tree, there's no guarantee you get nodes or properties out in the > > > same order as the original .dts file. > > > > That's why I raised the point. If people think encoding initialization > > order in the DT is a good idea, then we should change the dtc so it > > compiles/decompiles in the same order. > > I'm not actually sure what you mean by this. dtc already preserves > order between input and output.
This is an old comment (~ 1d, wow). My position has evolved to seeing if we can allow dtc to topsort nodes it can easily tell are needed first as an optimization. *Not* a requirement. Deferred probing would still be a fall back. thx, Jason. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
