Re: [PATCH v2 net-next 2/6] dt-bindings: net: Brcm ASP 2.0 Ethernet controller

[Justin Chen]

On Thu, Apr 27, 2023 at 10:16 AM Rob Herring <robh@xxxxxxxxxx> wrote:
>
> On Wed, Apr 26, 2023 at 11:54:28AM -0700, Justin Chen wrote:
> > From: Florian Fainelli <f.fainelli@xxxxxxxxx>
> >
> > Add a binding document for the Broadcom ASP 2.0 Ethernet
> > controller.
> >
> > Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> > Signed-off-by: Justin Chen <justinpopo6@xxxxxxxxx>
> > ---
> >  .../devicetree/bindings/net/brcm,asp-v2.0.yaml     | 145 +++++++++++++++++++++
> >  1 file changed, 145 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/net/brcm,asp-v2.0.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/net/brcm,asp-v2.0.yaml b/Documentation/devicetree/bindings/net/brcm,asp-v2.0.yaml
> > new file mode 100644
> > index 000000000000..818d91692e6e
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/net/brcm,asp-v2.0.yaml
> > @@ -0,0 +1,145 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/net/brcm,asp-v2.0.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Broadcom ASP 2.0 Ethernet controller
> > +
> > +maintainers:
> > +  - Justin Chen <justinpopo6@xxxxxxxxx>
> > +  - Florian Fainelli <f.fainelli@xxxxxxxxx>
> > +
> > +description: Broadcom Ethernet controller first introduced with 72165
> > +
> > +properties:
> > +  '#address-cells':
> > +    const: 1
> > +  '#size-cells':
> > +    const: 1
> > +
> > +  compatible:
> > +    enum:
> > +      - brcm,asp-v2.0
> > +      - brcm,bcm72165-asp-v2.0
> > +      - brcm,asp-v2.1
> > +      - brcm,bcm74165-asp-v2.1
>
> You have 1 SoC per version, so what's the point of versions? If you have
> more coming, then fine, but I'd expect it to be something like this:
>
> compatible = "brcm,bcm74165-asp-v2.1", "brcm,asp-v2.1";
>
> Also, the version in the SoC specific compatible is redundant. Just
> "brcm,bcm74165-asp" is enough.
>
> v2.1 is not compatible with v2.0? What that means is would a client/OS
> that only understands what v2.0 is work with v2.1 h/w? If so, you should
> have fallback compatible.
>
v2.1 is not compatible with v2.0 unfortunately. So no, a client/OS
that only understands v2.0 will not work with v2.1 h/w.

> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  ranges: true
> > +
> > +  interrupts:
> > +    minItems: 1
> > +    items:
> > +      - description: RX/TX interrupt
> > +      - description: Port 0 Wake-on-LAN
> > +      - description: Port 1 Wake-on-LAN
> > +
> > +  clocks:
> > +    maxItems: 1
> > +
> > +  ethernet-ports:
>
> The ethernet-switch.yaml schema doesn't work for you?
>
Technically it is not a switch. But it might work... If we use port to
reference the unimac and reg to reference the ethernet channel. I
rather not though, just cause it is not a switch, so calling it an
ethernet-switch is confusing.

> > +    type: object
> > +    properties:
> > +      '#address-cells':
> > +        const: 1
> > +      '#size-cells':
> > +        const: 0
> > +
> > +    patternProperties:
> > +      "^port@[0-9]+$":
> > +        type: object
> > +
> > +        $ref: ethernet-controller.yaml#
> > +
> > +        properties:
> > +          reg:
> > +            maxItems: 1
> > +            description: Port number
> > +
> > +          channel:
> > +            maxItems: 1
> > +            description: ASP channel number
>
> Not a standard property, so it needs a type and vendor prefix. However,
> what's the difference between channel and port? Can the port numbers
> correspond to the channels?
>
Port refers to the unimac. In our case we currently have a maximum of
2. Channel refers to the ethernet hardware channel proper, in which we
have many. So yes, you can have a port correlate to any channel.

> > +
> > +        required:
> > +          - reg
> > +          - channel
> > +
> > +    additionalProperties: false
> > +
> > +patternProperties:
> > +  "^mdio@[0-9a-f]+$":
> > +    type: object
> > +    $ref: "brcm,unimac-mdio.yaml"
>
> Drop quotes.
>
> > +
> > +    description:
> > +      ASP internal UniMAC MDIO bus
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupts
> > +  - clocks
> > +  - ranges
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> > +
> > +    ethernet@9c00000 {
> > +        compatible = "brcm,asp-v2.0";
> > +        reg = <0x9c00000 0x1fff14>;
> > +        interrupts = <GIC_SPI 51 IRQ_TYPE_LEVEL_HIGH>;
> > +        ranges;
> > +        clocks = <&scmi 14>;
> > +        #address-cells = <1>;
> > +        #size-cells = <1>;
> > +
> > +        mdio@c614 {
> > +            compatible = "brcm,asp-v2.0-mdio";
> > +            reg = <0xc614 0x8>;
>
> You have 1:1 ranges, is that really what you want? That means 0xc614 is
> an absolute address.
Ack, will fix.

Thanks for the review,
Justin

>
> > +            reg-names = "mdio";
> > +            #address-cells = <1>;
> > +            #size-cells = <0>;
> > +
> > +            phy0: ethernet-phy@1 {
> > +                reg = <1>;
> > +            };
> > +       };
> > +
> > +        mdio@ce14 {
> > +            compatible = "brcm,asp-v2.0-mdio";
> > +            reg = <0xce14 0x8>;
> > +            reg-names = "mdio";
> > +            #address-cells = <1>;
> > +            #size-cells = <0>;
> > +
> > +            phy1: ethernet-phy@1 {
> > +                reg = <1>;
> > +            };
> > +        };
> > +
> > +        ethernet-ports {
> > +            #address-cells = <1>;
> > +            #size-cells = <0>;
> > +
> > +            port@0 {
> > +                reg = <0>;
> > +                channel = <8>;
> > +                phy-mode = "rgmii";
> > +                phy-handle = <&phy0>;
> > +            };
> > +
> > +            port@1 {
> > +                reg = <1>;
> > +                channel = <9>;
> > +                phy-mode = "rgmii";
> > +                phy-handle = <&phy1>;
> > +            };
> > +        };
> > +    };
> > --
> > 2.7.4
> >