Re: [PATCH 07/10] ARM: dts: sun7i: cubietruck: Enable the GMAC

[Giuseppe CAVALLARO]

On 12/7/2013 2:57 AM, Florian Fainelli wrote:
> 2013/12/6 Chen-Yu Tsai <wens@xxxxxxxx>:
> > On Sat, Dec 7, 2013 at 5:09 AM, Florian Fainelli <f.fainelli@xxxxxxxxx> wrote:
> > > 2013/12/6 Chen-Yu Tsai <wens@xxxxxxxx>:
> > > > The CubieTruck uses the GMAC with an RGMII phy.
> > > >
> > > > Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>
> > > > ---
> > > >   arch/arm/boot/dts/sun7i-a20-cubietruck.dts | 8 ++++++++
> > > >   1 file changed, 8 insertions(+)
> > > >
> > > > diff --git a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
> > > > index 8a1009d..af212a2 100644
> > > > --- a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
> > > > +++ b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
> > > > @@ -33,6 +33,14 @@
> > > >                          pinctrl-0 = <&uart0_pins_a>;
> > > >                          status = "okay";
> > > >                  };
> > > > +
> > > > +               gmac: ethernet@01c50000 {
> > > > +                       pinctrl-names = "default";
> > > > +                       pinctrl-0 = <&gmac_pins_rgmii>;
> > > > +                       snps,phy-addr = <1>;
> > >
> > > What is this snps,phy-addr property? Why is not a standard device tree
> > > node for an Ethernet PHY node used?
> >
> > This property is implemented by stmmac and documented in the DT
> > bindings. stmmac has not been updated to use Ethernet PHY nodes.
>
> This driver property should be removed and deprecated since there is
> an ePAPR standardized Ethernet PHY node. What I am worried here is the
> loss of information, the standard Ethernet DT node allows to specify
> much more information (clause, maximum speed, compatible string
> etc...).


yes Florian you are right and I have already started updating the
driver. I do not sure that I'll be able to send all the patches soon
but for sure I can re-base them.

> > Removing this property will not affect the function of the driver.
> > The driver probes its MDIO bus and selects the lowest available
> > address if not specified.
>
> So if this is just giving the driver a hint on where to  probe for a
> PHY on the MDIO bus, then let's drop it and use the standard DT node
> no?
>
> > > > +                       phy-mode = "rgmii";
> > >
> > > Especially since you use the relatively standard "phy-mode" property here?
> >
> > Used as specified in stmmac DT bindings.
>
> That one is kind of okay because of_get_phy_mode() knows about it,
> even though ePAPR states this should be "phy-connection-type", so I am
> okay with keeping that one because current practice and helpers are
> here.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/