[PATCH v3 net-next 2/8] dt-bindings: net: mediatek: add WED RX binding for MT7986 eth driver

[Krzysztof Kozlowski]

On 03/11/2022 19:29, Lorenzo Bianconi wrote:
>> On 03/11/2022 13:51, Lorenzo Bianconi wrote:
>>>>> diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-boot.yaml b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-boot.yaml
>>>>> new file mode 100644
>>>>> index 000000000000..6c3c514c48ef
>>>>> --- /dev/null
>>>>> +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-boot.yaml
> 
> Regarding "mediatek,mt7986-wed" compatible string it has been added to
> mt7986a.dtsi in the commit below:
> 
> commit 00b9903996b3e1e287c748928606d738944e45de
> Author: Lorenzo Bianconi <lorenzo at kernel.org>
> Date:   Tue Sep 20 12:11:13 2022 +0200
> 
> arm64: dts: mediatek: mt7986: add support for Wireless Ethernet Dispatch
> 
>>>>
>>>> arm is only for top-level stuff. Choose appropriate subsystem, soc as
>>>> last resort.
>>>
>>> these chips are used only for networking so is net folder fine?
>>
>> So this is some MMIO and no actual device? Then rather soc.
> 
> ack, I will move them there
> 
>>
>>>
>>>>
>>>>> @@ -0,0 +1,47 @@
>>>>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>>>>> +%YAML 1.2
>>>>> +---
>>>>> +$id: http://devicetree.org/schemas/arm/mediatek/mediatek,mt7986-wo-boot.yaml#
>>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>>> +
>>>>> +title:
>>>>> +  MediaTek Wireless Ethernet Dispatch WO boot controller interface for MT7986
>>>>> +
>>>>> +maintainers:
>>>>> +  - Lorenzo Bianconi <lorenzo at kernel.org>
>>>>> +  - Felix Fietkau <nbd at nbd.name>
>>>>> +
>>>>> +description:
>>>>> +  The mediatek wo-boot provides a configuration interface for WED WO
>>>>> +  boot controller on MT7986 soc.
>>>>
>>>> And what is "WED WO boot controller?
>>>
>>> WED WO is a chip used for networking packet processing offloaded to the Soc
>>> (e.g. packet reordering). WED WO boot is the memory used to store start address
>>> of wo firmware. Anyway I will let Sujuan comment on this.
>>
>> A bit more should be in description.
> 
> I will let Sujuan adding more details (since I do not have them :))
> 
>>
>>>
>>>>
>>>>> +
>>>>> +properties:
>>>>> +  compatible:
>>>>> +    items:
>>>>> +      - enum:
>>>>> +          - mediatek,mt7986-wo-boot
>>>>> +      - const: syscon
>>>>> +
>>>>> +  reg:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +  interrupts:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +required:
>>>>> +  - compatible
>>>>> +  - reg
>>>>> +
>>>>> +additionalProperties: false
>>>>> +
>>>>> +examples:
>>>>> +  - |
>>>>> +    soc {
>>>>> +      #address-cells = <2>;
>>>>> +      #size-cells = <2>;
>>>>> +
>>>>> +      wo_boot: syscon at 15194000 {
>>>>> +        compatible = "mediatek,mt7986-wo-boot", "syscon";
>>>>> +        reg = <0 0x15194000 0 0x1000>;
>>>>> +      };
>>>>> +    };
>>>>> diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-ccif.yaml b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-ccif.yaml
>>>>> new file mode 100644
>>>>> index 000000000000..6357a206587a
>>>>> --- /dev/null
>>>>> +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-ccif.yaml
>>>>> @@ -0,0 +1,50 @@
>>>>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>>>>> +%YAML 1.2
>>>>> +---
>>>>> +$id: http://devicetree.org/schemas/arm/mediatek/mediatek,mt7986-wo-ccif.yaml#
>>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>>> +
>>>>> +title: MediaTek Wireless Ethernet Dispatch WO controller interface for MT7986
>>>>> +
>>>>> +maintainers:
>>>>> +  - Lorenzo Bianconi <lorenzo at kernel.org>
>>>>> +  - Felix Fietkau <nbd at nbd.name>
>>>>> +
>>>>> +description:
>>>>> +  The mediatek wo-ccif provides a configuration interface for WED WO
>>>>> +  controller on MT7986 soc.
>>>>
>>>> All previous comments apply.
>>>>
>>>>> +
>>>>> +properties:
>>>>> +  compatible:
>>>>> +    items:
>>>>> +      - enum:
>>>>> +          - mediatek,mt7986-wo-ccif
>>>>> +      - const: syscon
>>>>> +
>>>>> +  reg:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +  interrupts:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +required:
>>>>> +  - compatible
>>>>> +  - reg
>>>>> +  - interrupts
>>>>> +
>>>>> +additionalProperties: false
>>>>> +
>>>>> +examples:
>>>>> +  - |
>>>>> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
>>>>> +    #include <dt-bindings/interrupt-controller/irq.h>
>>>>> +    soc {
>>>>> +      #address-cells = <2>;
>>>>> +      #size-cells = <2>;
>>>>> +
>>>>> +      wo_ccif0: syscon at 151a5000 {
>>>>> +        compatible = "mediatek,mt7986-wo-ccif", "syscon";
>>>>> +        reg = <0 0x151a5000 0 0x1000>;
>>>>> +        interrupts = <GIC_SPI 205 IRQ_TYPE_LEVEL_HIGH>;
>>>>> +      };
>>>>> +    };
>>>>> diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-dlm.yaml b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-dlm.yaml
>>>>> new file mode 100644
>>>>> index 000000000000..a499956d9e07
>>>>> --- /dev/null
>>>>> +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt7986-wo-dlm.yaml
>>>>> @@ -0,0 +1,50 @@
>>>>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>>>>> +%YAML 1.2
>>>>> +---
>>>>> +$id: http://devicetree.org/schemas/arm/mediatek/mediatek,mt7986-wo-dlm.yaml#
>>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>>> +
>>>>> +title: MediaTek Wireless Ethernet Dispatch WO hw rx ring interface for MT7986
>>>>> +
>>>>> +maintainers:
>>>>> +  - Lorenzo Bianconi <lorenzo at kernel.org>
>>>>> +  - Felix Fietkau <nbd at nbd.name>
>>>>> +
>>>>> +description:
>>>>> +  The mediatek wo-dlm provides a configuration interface for WED WO
>>>>> +  rx ring on MT7986 soc.
>>>>> +
>>>>> +properties:
>>>>> +  compatible:
>>>>> +    const: mediatek,mt7986-wo-dlm
>>>>> +
>>>>> +  reg:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +  resets:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +  reset-names:
>>>>> +    maxItems: 1
>>>>> +
>>>>> +required:
>>>>> +  - compatible
>>>>> +  - reg
>>>>> +  - resets
>>>>> +  - reset-names
>>>>> +
>>>>> +additionalProperties: false
>>>>> +
>>>>> +examples:
>>>>> +  - |
>>>>> +    soc {
>>>>> +      #address-cells = <2>;
>>>>> +      #size-cells = <2>;
>>>>> +
>>>>> +      wo_dlm0: wo-dlm at 151e8000 {
>>>>
>>>> Node names should be generic.
>>>> https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
>>>
>>> DLM is a chip used to store the data rx ring of wo firmware. I do not have a
>>> better node name (naming is always hard). Can you please suggest a better name?
>>
>> The problem is that you added three new devices which seem to be for the
>> same device - WED. It looks like some hacky way of avoid proper hardware
>> description - let's model everything as MMIO and syscons...
> 
> is it fine to use syscon as node name even if we do not declare it in compatible
> string for dlm?
> 

No, rather not. It's a shortcut and if used without actual syscon it
would be confusing. You could still call it system-controller, though.

Best regards,
Krzysztof