Re: Re: [PATCH V2] ethernet: stmmac: support driver work for DTs without child queue node

Re: Re: [PATCH V2] ethernet: stmmac: support driver work for DTs without child queue node

[Andrew Lunn]

Adding device tree list.

This is mostly a device tree issue, so the device tree Maintainers
should be part of the discussion.

> >On Fri, Apr 29, 2022 at 08:46:05AM +0800, Jianqun Xu wrote:
> >> The driver use the value of property 'snps,rx-queues-to-use' to loop
> >> same numbers child nodes as queues, such as:
> >>
> >>     gmac {
> >>         rx-queues-config {
> >>             snps,rx-queues-to-use = <1>;
> >>             queue0 {
> >>                 // nothing need here.
> >>     };
> >> };
> >>     };
> >>
> >> Since a patch for dtc from rockchip will delete all node without any
> >> properties or child node, the queue0 node will be deleted, that caused
> >> the driver fail to probe:
> >
> >Is this the in tree dtc? Do you have a commit hash for it? That should
> >probably be used as a Fixes: tag. Or that change to dtc needs
> >reverting because it breaks stuff.
> > 
> The patch is a hack patch for some products and have not in tree dtc, I said that to
> explain a possible case how things happed, it's only a case of no child queue node.

So this has nothing to do with the kernel dtc, or the upstream
dtc. This is only a 'vendor crap' dtc which has been hacked?

Why should mainline care? Is there anything in the DT standard which
says the compiler can optimise out empty properties?

     Andrew