Re: [PATCH 06/10] dt-bindings: ufs: Add compatibles for S32N79 Host Controller platform driver

[Frank Li <Frank.li@oss.nxp.com>]

On Wed, Aug 26, 2026 at 03:40:44PM +0200, Larisa Grigore wrote:
> [You don't often get email from larisa.grigore@oss.nxp.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>
> Document the device tree binding for the NXP S32N79 DWC-based UFS host
> controller which is compliant with JESD-223D "Universal Flash Storage Host
> Controller Interface" v3.0.
>
> The controller requires access to the SCM register block and the core
> clock rate when M-PHY initialization is performed. Add the optional
> nxp,mphy-boot-mode property to select the M-PHY firmware execution
> environment.
> Currently, the M-PHY firmware can only run from ROM. If the property is
> omitted, M-PHY initialization is assumed to be handled externally.
>
> Signed-off-by: Larisa Grigore <larisa.grigore@oss.nxp.com>
> ---
>  .../bindings/ufs/nxp,s32n7-ufshc.yaml         | 99 +++++++++++++++++++
>  1 file changed, 99 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/ufs/nxp,s32n7-ufshc.yaml
>
> diff --git a/Documentation/devicetree/bindings/ufs/nxp,s32n7-ufshc.yaml b/Documentation/devicetree/bindings/ufs/nxp,s32n7-ufshc.yaml
> new file mode 100644
> index 000000000000..d9d5669be313
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/ufs/nxp,s32n7-ufshc.yaml
> @@ -0,0 +1,99 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/ufs/nxp,s32n7-ufshc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NXP S32N79 Universal Flash Storage (UFS) Controller
> +
> +maintainers:
> +  - Larisa Grigore <larisa.grigore@oss.nxp.com>
> +
> +# Select only our matches, not all jedec,ufs
> +select:
> +  properties:
> +    compatible:
> +      contains:
> +        const: nxp,s32n79-ufshc
> +  required:
> +    - compatible
> +
> +properties:
> +  compatible:
> +    items:
> +      - const: nxp,s32n79-ufshc
> +      - const: jedec,ufs-3.0

Any place actually use this fallback?

> +
> +  reg:
> +    minItems: 1
> +    items:
> +      - description: UFS Host Controller registers
> +      - description: System Control Module registers
> +
> +  reg-names:
> +    description: |
> +      Names for the register regions. The first entry must be "ufshc".
> +      The second entry "scm" is mandatory only when nxp,mphy-boot-mode
> +      property is present.

you already us if - else branch to restrict this limition, needn't
description here.

> +    minItems: 1
> +    items:
> +      - const: ufshc
> +      - const: scm
> +
> +  clocks:
> +    maxItems: 1
> +    description: UFS core clock
> +
> +  clock-names:
> +    items:
> +      - const: core_clk

Needn't suffix _clk, just "core", generally needn't clock-names if only
one clocks.

> +
> +  nxp,mphy-boot-mode:
> +    description: |
> +      MPHY initialization mode. Defines how the MPHY firmware should be
> +      initialized and executed during UFS controller startup.
> +      If this property is not specified, MPHY initialization will be skipped.
> +    $ref: /schemas/types.yaml#/definitions/string
> +    enum:
> +      - rom

why not use standard "phy" property, if no "phy" means ROM init it.

Frank
> +
> +required:
> +  - compatible
> +  - reg
> +
> +allOf:
> +  - $ref: ufs-common.yaml
> +  - if:
> +      required:
> +        - nxp,mphy-boot-mode
> +    then:
> +      properties:
> +        reg:
> +          minItems: 2
> +        reg-names:
> +          minItems: 2
> +      required:
> +        - reg-names
> +        - clocks
> +        - clock-names
> +    else:
> +      properties:
> +        reg:
> +          maxItems: 1
> +        reg-names:
> +          maxItems: 1
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    ufshc@4ac80000 {
> +        compatible = "nxp,s32n79-ufshc", "jedec,ufs-3.0";
> +        reg = <0x4ac80000 0x1000>, <0x4ac40000 0x1000>;
> +        reg-names = "ufshc", "scm";
> +        interrupt-parent = <&irqsteer_coss>;
> +        interrupts = <211>;
> +        clocks = <&sys_clk>;
> +        clock-names = "core_clk";
> +        nxp,mphy-boot-mode = "rom";
> +    };
> --
> 2.43.0
>
>