Re: [PATCH v2 2/5] dt-bindings: net: add schema for NXP S32CC dwmac glue driver

[Krzysztof Kozlowski]

On 28/11/2022 06:49, Chester Lin wrote:
> Add the DT schema for the DWMAC Ethernet controller on NXP S32 Common
> Chassis.
> 
> Signed-off-by: Jan Petrous <jan.petrous@xxxxxxx>
> Signed-off-by: Chester Lin <clin@xxxxxxxx>

Thank you for your patch. There is something to discuss/improve.

> ---
> 
> Changes in v2:
>   - Fix schema issues.
>   - Add minItems to clocks & clock-names.
>   - Replace all sgmii/SGMII terms with pcs/PCS.
> 
>  .../bindings/net/nxp,s32cc-dwmac.yaml         | 135 ++++++++++++++++++
>  1 file changed, 135 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/net/nxp,s32cc-dwmac.yaml
> 
> diff --git a/Documentation/devicetree/bindings/net/nxp,s32cc-dwmac.yaml b/Documentation/devicetree/bindings/net/nxp,s32cc-dwmac.yaml
> new file mode 100644
> index 000000000000..c6839fd3df40
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/nxp,s32cc-dwmac.yaml
> @@ -0,0 +1,135 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright 2021-2022 NXP
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/net/nxp,s32cc-dwmac.yaml#";
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#";

Drop quotes from both.

> +
> +title: NXP S32CC DWMAC Ethernet controller
> +
> +maintainers:
> +  - Jan Petrous <jan.petrous@xxxxxxx>
> +  - Chester Lin <clin@xxxxxxxx>
> +
> +allOf:
> +  - $ref: "snps,dwmac.yaml#"

Drop quotes.

> +
> +properties:
> +  compatible:
> +    enum:
> +      - nxp,s32cc-dwmac
> +
> +  reg:
> +    items:
> +      - description: Main GMAC registers
> +      - description: S32 MAC control registers
> +
> +  dma-coherent: true
> +
> +  clocks:
> +    minItems: 5

Why only 5 clocks are required? Receive clocks don't have to be there?
Is such system - only with clocks for transmit - usable?

> +    items:
> +      - description: Main GMAC clock
> +      - description: Peripheral registers clock
> +      - description: Transmit PCS clock
> +      - description: Transmit RGMII clock
> +      - description: Transmit RMII clock
> +      - description: Transmit MII clock
> +      - description: Receive PCS clock
> +      - description: Receive RGMII clock
> +      - description: Receive RMII clock
> +      - description: Receive MII clock
> +      - description:
> +          PTP reference clock. This clock is used for programming the
> +          Timestamp Addend Register. If not passed then the system
> +          clock will be used.
> +
> +  clock-names:
> +    minItems: 5
> +    items:
> +      - const: stmmaceth
> +      - const: pclk
> +      - const: tx_pcs
> +      - const: tx_rgmii
> +      - const: tx_rmii
> +      - const: tx_mii
> +      - const: rx_pcs
> +      - const: rx_rgmii
> +      - const: rx_rmii
> +      - const: rx_mii
> +      - const: ptp_ref
> +
> +  tx-fifo-depth:
> +    const: 20480
> +
> +  rx-fifo-depth:
> +    const: 20480
> +
> +required:
> +  - compatible
> +  - reg
> +  - tx-fifo-depth
> +  - rx-fifo-depth
> +  - clocks
> +  - clock-names
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    #define S32GEN1_SCMI_CLK_GMAC0_AXI
> +    #define S32GEN1_SCMI_CLK_GMAC0_TX_PCS
> +    #define S32GEN1_SCMI_CLK_GMAC0_TX_RGMII
> +    #define S32GEN1_SCMI_CLK_GMAC0_TX_RMII
> +    #define S32GEN1_SCMI_CLK_GMAC0_TX_MII
> +    #define S32GEN1_SCMI_CLK_GMAC0_RX_PCS
> +    #define S32GEN1_SCMI_CLK_GMAC0_RX_RGMII
> +    #define S32GEN1_SCMI_CLK_GMAC0_RX_RMII
> +    #define S32GEN1_SCMI_CLK_GMAC0_RX_MII
> +    #define S32GEN1_SCMI_CLK_GMAC0_TS

Why defines? Your clock controller is not ready? If so, just use raw
numbers.

> +
> +    soc {
> +      #address-cells = <1>;
> +      #size-cells = <1>;
> +
> +      gmac0: ethernet@4033c000 {
> +        compatible = "nxp,s32cc-dwmac";
> +        reg = <0x4033c000 0x2000>, /* gmac IP */
> +              <0x4007C004 0x4>;    /* S32 CTRL_STS reg */

Lowercase hex.

> +        interrupt-parent = <&gic>;
> +        interrupts = <GIC_SPI 57 IRQ_TYPE_LEVEL_HIGH>;
> +        interrupt-names = "macirq";
> +        phy-mode = "rgmii-id";
> +        tx-fifo-depth = <20480>;
> +        rx-fifo-depth = <20480>;
> +        dma-coherent;
> +        clocks = <&clks S32GEN1_SCMI_CLK_GMAC0_AXI>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_AXI>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_TX_PCS>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_TX_RGMII>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_TX_RMII>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_TX_MII>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_RX_PCS>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_RX_RGMII>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_RX_RMII>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_RX_MII>,
> +                 <&clks S32GEN1_SCMI_CLK_GMAC0_TS>;


Best regards,
Krzysztof