Subject: Re: [PATCH 07/25] dt-bindings: net: dwmac: Detach Generic DW MAC bindings

From: Rob Herring <[email-masked]>
Date: Tue, 15 Dec 2020 11:50:02 -0600

On Mon, Dec 14, 2020 at 12:15:57PM +0300, Serge Semin wrote:
> Currently the snps,dwmac.yaml DT bindings file is used for both DT nodes
> describing generic DW MAC devices and as DT schema with common properties
> to be evaluated against a vendor-specific DW MAC IP-cores. Due to such
> dual-purpose design the "compatible" property of the common DW MAC schema
> needs to contain the vendor-specific strings to successfully pass the
> schema evaluation in case if it's referenced from the vendor-specific DT
> bindings. That's a bad design from maintainability point of view, since
> adding/removing any DW MAC-based device bindings requires the common
> schema modification. In order to fix that let's detach the schema which
> provides the generic DW MAC DT nodes evaluation into a dedicated DT
> bindings file preserving the common DW MAC properties declaration in the
> snps,dwmac.yaml file. By doing so we'll still provide a common properties
> evaluation for each vendor-specific MAC bindings which refer to the
> common bindings file, while the generic DW MAC DT nodes will be checked
> against the new snps,dwmac-generic.yaml DT schema.

I'm okay with the change, but it needs a big fat note that 
snps,dwmac-generic.yaml should not have new users. New users should have 
an SoC specific compatible. History has shown that even IP versions are 
not enough to handle all the integration crap vendors do.

> 
> Signed-off-by: Serge Semin <[email-masked]>
> ---
>  .../bindings/net/snps,dwmac-generic.yaml      | 148 ++++++++++++++++++
>  .../devicetree/bindings/net/snps,dwmac.yaml   | 139 +---------------
>  2 files changed, 149 insertions(+), 138 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml
> 
> diff --git a/Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml b/Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml
> new file mode 100644
> index 000000000000..f1b387911390
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/snps,dwmac-generic.yaml
> @@ -0,0 +1,148 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/snps,dwmac-generic.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Synopsys DesignWare Generic MAC Device Tree Bindings
> +
> +maintainers:
> +  - Alexandre Torgue <[email-masked]>
> +  - Giuseppe Cavallaro <[email-masked]>
> +  - Jose Abreu <[email-masked]>
> +
> +# Select the DT nodes, which have got compatible strings either as just a
> +# single string with IP-core name optionally followed by the IP version or
> +# two strings: one with IP-core name plus the IP version, another as just
> +# the IP-core name.
> +select:
> +  properties:
> +    compatible:
> +      oneOf:
> +        - items:
> +            - pattern: "^snps,dw(xg)+mac(-[0-9]+\\.[0-9]+a?)?$"
> +        - items:
> +            - pattern: "^snps,dwmac-[0-9]+\\.[0-9]+a?$"
> +            - const: snps,dwmac
> +        - items:
> +            - pattern: "^snps,dwxgmac-[0-9]+\\.[0-9]+a?$"
> +            - const: snps,dwxgmac
> +
> +  required:
> +    - compatible
> +
> +allOf:
> +  - $ref: snps,dwmac.yaml#
> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - description: Generic Synopsys DW MAC
> +        oneOf:
> +          - items:
> +              - enum:
> +                  - snps,dwmac-3.50a
> +                  - snps,dwmac-3.610
> +                  - snps,dwmac-3.70a
> +                  - snps,dwmac-3.710
> +                  - snps,dwmac-4.00
> +                  - snps,dwmac-4.10a
> +                  - snps,dwmac-4.20a
> +              - const: snps,dwmac
> +          - const: snps,dwmac
> +      - description: Generic Synopsys DW xGMAC
> +        oneOf:
> +          - items:
> +              - enum:
> +                  - snps,dwxgmac-2.10
> +              - const: snps,dwxgmac
> +          - const: snps,dwxgmac
> +      - description: ST SPEAr SoC Family GMAC
> +        deprecated: true
> +        const: st,spear600-gmac
> +
> +  reg:
> +    maxItems: 1
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    gmac0: ethernet@e0800000 {
> +      compatible = "snps,dwxgmac-2.10", "snps,dwxgmac";
> +      reg = <0xe0800000 0x8000>;
> +      interrupt-parent = <&vic1>;
> +      interrupts = <24 23 22>;
> +      interrupt-names = "macirq", "eth_wake_irq", "eth_lpi";
> +      mac-address = [000000000000]; /* Filled in by U-Boot */
> +      max-frame-size = <3800>;
> +      phy-mode = "gmii";
> +      snps,multicast-filter-bins = <256>;
> +      snps,perfect-filter-entries = <128>;
> +      rx-fifo-depth = <16384>;
> +      tx-fifo-depth = <16384>;
> +      clocks = <&clock>;
> +      clock-names = "stmmaceth";
> +      snps,axi-config = <&stmmac_axi_setup>;
> +      snps,mtl-rx-config = <&mtl_rx_setup>;
> +      snps,mtl-tx-config = <&mtl_tx_setup>;
> +      mdio0 {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        compatible = "snps,dwmac-mdio";
> +        phy1: ethernet-phy@0 {
> +          reg = <0>;
> +        };
> +      };
> +    };
> +  - |
> +    gmac1: ethernet@f8010000 {
> +      compatible = "snps,dwmac-4.10a", "snps,dwmac";
> +      reg = <0xf8010000 0x4000>;
> +      interrupts = <0 98 4>;
> +      interrupt-names = "macirq";
> +      clock-names = "stmmaceth", "ptp_ref";
> +      clocks = <&clock 4>, <&clock 5>;
> +      phy-mode = "rgmii";
> +      snps,txpbl = <8>;
> +      snps,rxpbl = <2>;
> +      snps,aal;
> +      snps,tso;
> +
> +      snps,axi-config {
> +        snps,wr_osr_lmt = <0xf>;
> +        snps,rd_osr_lmt = <0xf>;
> +        snps,blen = <256 128 64 32 0 0 0>;
> +      };
> +
> +      snps,mtl-rx-config {
> +        snps,rx-queues-to-use = <1>;
> +        snps,rx-sched-sp;
> +        queue0 {
> +          snps,dcb-algorithm;
> +          snps,map-to-dma-channel = <0x0>;
> +          snps,priority = <0x0>;
> +        };
> +      };
> +
> +      snps,mtl-tx-config {
> +        snps,tx-queues-to-use = <2>;
> +        snps,tx-sched-wrr;
> +
> +        queue0 {
> +          snps,weight = <0x10>;
> +          snps,dcb-algorithm;
> +          snps,priority = <0x0>;
> +        };
> +
> +        queue1 {
> +          snps,avb-algorithm;
> +          snps,send_slope = <0x1000>;
> +          snps,idle_slope = <0x1000>;
> +          snps,high_credit = <0x3E800>;
> +          snps,low_credit = <0x1FC18000>;
> +          snps,priority = <0x1>;
> +        };
> +      };
> +    };
> +...
> diff --git a/Documentation/devicetree/bindings/net/snps,dwmac.yaml b/Documentation/devicetree/bindings/net/snps,dwmac.yaml
> index 74820f491346..72b58f86bc41 100644
> --- a/Documentation/devicetree/bindings/net/snps,dwmac.yaml
> +++ b/Documentation/devicetree/bindings/net/snps,dwmac.yaml
> @@ -11,31 +11,7 @@ maintainers:
>    - Giuseppe Cavallaro <[email-masked]>
>    - Jose Abreu <[email-masked]>
>  
> -# Select every compatible, including the deprecated ones. This way, we
> -# will be able to report a warning when we have that compatible, since
> -# we will validate the node thanks to the select, but won't report it
> -# as a valid value in the compatible property description
> -select:
> -  properties:
> -    compatible:
> -      contains:
> -        enum:
> -          - snps,dwmac
> -          - snps,dwmac-3.50a
> -          - snps,dwmac-3.610
> -          - snps,dwmac-3.70a
> -          - snps,dwmac-3.710
> -          - snps,dwmac-4.00
> -          - snps,dwmac-4.10a
> -          - snps,dwmac-4.20a
> -          - snps,dwxgmac
> -          - snps,dwxgmac-2.10
> -
> -          # Deprecated
> -          - st,spear600-gmac
> -
> -  required:
> -    - compatible
> +select: false
>  
>  allOf:
>    - $ref: "ethernet-controller.yaml#"
> @@ -62,35 +38,6 @@ allOf:
>              MAC HW capability register.
>  
>  properties:
> -
> -  # We need to include all the compatibles from schemas that will
> -  # include that schemas, otherwise compatible won't validate for
> -  # those.
> -  compatible:
> -    contains:
> -      enum:
> -        - allwinner,sun7i-a20-gmac
> -        - allwinner,sun8i-a83t-emac
> -        - allwinner,sun8i-h3-emac
> -        - allwinner,sun8i-r40-emac
> -        - allwinner,sun8i-v3s-emac
> -        - allwinner,sun50i-a64-emac
> -        - amlogic,meson6-dwmac
> -        - amlogic,meson8b-dwmac
> -        - amlogic,meson8m2-dwmac
> -        - amlogic,meson-gxbb-dwmac
> -        - amlogic,meson-axg-dwmac
> -        - snps,dwmac
> -        - snps,dwmac-3.50a
> -        - snps,dwmac-3.610
> -        - snps,dwmac-3.70a
> -        - snps,dwmac-3.710
> -        - snps,dwmac-4.00
> -        - snps,dwmac-4.10a
> -        - snps,dwmac-4.20a
> -        - snps,dwxgmac
> -        - snps,dwxgmac-2.10
> -
>    reg:
>      minItems: 1
>      maxItems: 2
> @@ -543,88 +490,4 @@ dependencies:
>    snps,reset-delay-us: ["snps,reset-gpio"]
>  
>  additionalProperties: true
> -
> -examples:
> -  - |
> -    gmac0: ethernet@e0800000 {
> -        compatible = "snps,dwxgmac-2.10", "snps,dwxgmac";
> -        reg = <0xe0800000 0x8000>;
> -        interrupt-parent = <&vic1>;
> -        interrupts = <24 23 22>;
> -        interrupt-names = "macirq", "eth_wake_irq", "eth_lpi";
> -        mac-address = [000000000000]; /* Filled in by U-Boot */
> -        max-frame-size = <3800>;
> -        phy-mode = "gmii";
> -        snps,multicast-filter-bins = <256>;
> -        snps,perfect-filter-entries = <128>;
> -        rx-fifo-depth = <16384>;
> -        tx-fifo-depth = <16384>;
> -        clocks = <&clock>;
> -        clock-names = "stmmaceth";
> -        snps,axi-config = <&stmmac_axi_setup>;
> -        snps,mtl-rx-config = <&mtl_rx_setup>;
> -        snps,mtl-tx-config = <&mtl_tx_setup>;
> -        mdio0 {
> -            #address-cells = <1>;
> -            #size-cells = <0>;
> -            compatible = "snps,dwmac-mdio";
> -            phy1: ethernet-phy@0 {
> -                reg = <0>;
> -            };
> -        };
> -    };
> -  - |
> -    gmac1: ethernet@f8010000 {
> -        compatible = "snps,dwmac-4.10a", "snps,dwmac";
> -        reg = <0xf8010000 0x4000>;
> -        interrupts = <0 98 4>;
> -        interrupt-names = "macirq";
> -        clock-names = "stmmaceth", "ptp_ref";
> -        clocks = <&clock 4>, <&clock 5>;
> -        phy-mode = "rgmii";
> -        snps,txpbl = <8>;
> -        snps,rxpbl = <2>;
> -        snps,aal;
> -        snps,tso;
> -
> -        snps,axi-config {
> -            snps,wr_osr_lmt = <0xf>;
> -            snps,rd_osr_lmt = <0xf>;
> -            snps,blen = <256 128 64 32 0 0 0>;
> -        };
> -
> -        snps,mtl-rx-config {
> -            snps,rx-queues-to-use = <1>;
> -            snps,rx-sched-sp;
> -            queue0 {
> -               snps,dcb-algorithm;
> -               snps,map-to-dma-channel = <0x0>;
> -               snps,priority = <0x0>;
> -            };
> -        };
> -
> -        snps,mtl-tx-config {
> -            snps,tx-queues-to-use = <2>;
> -            snps,tx-sched-wrr;
> -            queue0 {
> -                snps,weight = <0x10>;
> -                snps,dcb-algorithm;
> -                snps,priority = <0x0>;
> -            };
> -
> -            queue1 {
> -                snps,avb-algorithm;
> -                snps,send_slope = <0x1000>;
> -                snps,idle_slope = <0x1000>;
> -                snps,high_credit = <0x3E800>;
> -                snps,low_credit = <0xFFC18000>;
> -                snps,priority = <0x1>;
> -            };
> -        };
> -    };
> -
> -# FIXME: We should set it, but it would report all the generic
> -# properties as additional properties.
> -# additionalProperties: false
> -
>  ...
> -- 
> 2.29.2
>