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

[Scott Wood]

On Mon, 2014-07-28 at 06:51 +0000, Emil Medve wrote:
> Hello Scott,
> 
> 
> Scott Wood <scottwood <at> freescale.com> writes:
> > On Wed, 2014-07-16 at 15:17 -0500, Shruti Kanetkar wrote:
> > > +			mdio <at> fd000 {
> > > +				/* For 10g interfaces */
> > > +				phy_xaui_slot1: xaui-phy <at> slot1 {
> > > +					status = "disabled";
> > > +					compatible = "ethernet-phy-ieee802.3-c45";
> > > +					reg = <0x7>; /* default switch setting on slot1 of AMC2PEX */
> > > +				};
> > 
> > Why xaui-phy and not ethernet-phy?
> > 
> > As for the device_type discussion from v1, there is a generic binding
> > that says device_type "should" be ethernet-phy.
> 
> I have no strong feelings about this and we can use ethernet-phy, but:
> 
> 1. The binding is old/stale (?) as it still uses device_type and the kernel
> doesn't seem to use anymore the device_type for PHY(s)

Yes.

> 2. The binding asks "ethernet-phy" for the device_type property, not for the
> name. As such TBI PHY(s) use (upstream) the tbi-phy@ node name

It shows ethernet-phy as the name in the example.  ePAPR urges generic
node names (this was also a recommendation for IEEE1275), and has
ethernet-phy on the preferred list.  Is a xaui-phy not an ethernet phy?

> > > +			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?

-Scott