[PATCH v2 5/7] powerpc/corenet: Add MDIO bus muxing support to the board device tree(s)

[Scott Wood]

On Wed, 2014-07-30 at 23:35 -0500, Emil Medve wrote:
> Hello Scott,
> 
> 
> On 07/30/2014 09:30 PM, Scott Wood wrote:
> > On Wed, 2014-07-30 at 16:52 -0500, Emil Medve wrote:
> >>>>>> +			mdio0: mdio <at> fc000 {
> >>>>>> +			};
> >>>>>
> >>>>> Why is the empty node needed?
> >>>>
> >>>> For the label
> >>>
> >>> For mdio-parent-bus, or is there some other dts layer that makes this
> >>> node non-empty?
> >>
> >> 'powerpc/corenet: Create the dts components for the DPAA FMan' -
> >> http://patchwork.ozlabs.org/patch/370872
> > 
> > Why does this patch define the mdio0 label for mdio at e1120, but not
> > define a label for any other node?
> 
> Only MDIO controllers that are pinned out have these labels. Only pinned
> out MDIO(s) are capable of controlling external PHY(s) via these board
> level MDIO buses

Is there any reason to describe non-pinned-out MDIO controllers at all?
Is the lack of pinning out inherent to the silicon, or is it board
design/config?  Is the answer different for different MDIO controllers?
I'm just curious why mdio at e1120 is labelled in a non-board dtsi while
others are labelled elsewhere.

-Scott