Subject: Re: [PATCH net-next 08/12] dt-bindings: net: toshiba,tc965x-dwmac: add TC956x Ethernet bridge

From: Daniel Thompson <[email-masked]>
Date: Thu, 7 May 2026 15:47:06 +0100

On Mon, May 04, 2026 at 01:00:07PM +0200, Krzysztof Kozlowski wrote:
> On Fri, May 01, 2026 at 10:54:16AM -0500, Alex Elder wrote:
> > From: Daniel Thompson <[email-masked]>
> >
> > Add devicetree bindings for the Toshiba TC956x family of Ethernet-AVB/TSN
> > bridges.
> >
> > Signed-off-by: Daniel Thompson <[email-masked]>
> > Signed-off-by: Alex Elder <[email-masked]>

Alex already replied to most of your comments but on this one
specifically...

> > ---
> >  .../bindings/net/toshiba,tc956x-dwmac.yaml    | 111 ++++++++++++++++++
> >  1 file changed, 111 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/net/toshiba,tc956x-dwmac.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/net/toshiba,tc956x-dwmac.yaml b/Documentation/devicetree/bindings/net/toshiba,tc956x-dwmac.yaml
> > new file mode 100644
> > index 0000000000000..d95d22a3761da
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/net/toshiba,tc956x-dwmac.yaml
> > @@ -0,0 +1,111 @@
> > <snip>
> > +examples:
> > +  - |
> > +    pcie {
> > +      #address-cells = <3>;
> > +      #size-cells = <2>;
> > +
> > +      tc956x_emac0: pci@0,0 {
> > +        compatible = "pci1179,0220";
> > +        reg = <0x50000 0x0 0x0 0x0 0x0>;
> > +        #address-cells = <3>;
> > +        #size-cells = <2>;
> > +        device_type = "pci";
> > +        ranges;
> > +
> > +        gpio-controller;
> > +        #gpio-cells = <2>;
> > +
> > +        phy-mode = "10gbase-r";
> > +        phy-handle = <&tc956x_emac0_phy>;
> > +
> > +        mdio {
> > +          compatible = "snps,dwmac-mdio";
> > +          #address-cells = <1>;
> > +          #size-cells = <0>;
> > +
> > +          tc956x_emac0_phy: ethernet-phy@1c {
> > +            compatible = "ethernet-phy-id311c.1c12";
> > +            reg = <0x1c>;
> > +          };
> > +        };
> > +      };
>
> Keep only one example, unless you have different properties (not their
> values, but their presence),

At some point I simplified the example by stripping out excess
properties from each ethernet-phy. In the process it looks like I
removed too much and eliminated reason I thought it important to
include both PCI functions in the example!

Each ethernet-phy will typically describe a reset gpio but we expect
only eMAC0 to act as a gpio-controller. For that reason I wanted to
show that. You can see part of that that in the current example because
tc956x_emac1 is not a gpio-controller.

In other words tc956x_emac**1**_phy will, in the real world, include a
reset-gpios property that references tc956x_emac**0**. For example:

    reset-gpios = <&tc956x_emac0 1 GPIO_ACTIVE_LOW>

So... is it better to strip it back the example to describe only a
single PCI function or should I add back the reset-gpios that I
accidentally removed?

Daniel.