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

[Emil Medve]

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)

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

> BTW, that binding
> (net/phy.txt) could use some cleaning up -- it still has references to
> things like linux,phandle.
> 
> > diff --git a/arch/powerpc/boot/dts/b4qds.dtsi
b/arch/powerpc/boot/dts/b4qds.dtsi
> > index 8b47edc..6188583 100644
> > --- a/arch/powerpc/boot/dts/b4qds.dtsi
> > +++ b/arch/powerpc/boot/dts/b4qds.dtsi
> >  <at>  <at>  -39,6 +39,13  <at>  <at> 
> >  	#size-cells = <2>;
> >  	interrupt-parent = <&mpic>;
> >  
> > +	aliases {
> > +		phy_sgmii_10 = &phy_sgmii_10;
> > +		phy_sgmii_11 = &phy_sgmii_11;
> > +		phy_sgmii_1c = &phy_sgmii_1c;
> > +		phy_sgmii_1d = &phy_sgmii_1d;
> > +	};
> 
> Is the encoding of these alias strings considered ABI (for either the
> OS's use or U-Boot's)?

U-Boot uses these aliases

> If so, please document it.

Will do

> If not, how do you
> see this being used?  What does the hex number mean from the user's
> perspective?
> 
> > +			mdio0: mdio <at> fc000 {
> > +			};
> 
> Why is the empty node needed?

For the label


Cheers,