Re: [PATCH v3 03/11] dt-bindings: memory: Document Tegra114 Memory Controller

Rob Herring
2025-09-22T16:00:41Z

On Mon, Sep 15, 2025 at 11:01:49AM +0300, Svyatoslav Ryhel wrote:
> Add Tegra114 support into existing Tegra124 MC schema with the most
> notable difference in the amount of EMEM timings.
>
> Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
> ---
> .../nvidia,tegra124-mc.yaml | 97 ++++++++++++++-----
> 1 file changed, 74 insertions(+), 23 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra124-mc.yaml b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra124-mc.yaml
> index 7b18b4d11e0a..9cc9360d3bd0 100644
> --- a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra124-mc.yaml
> +++ b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra124-mc.yaml
> @@ -19,7 +19,9 @@ description: |
>
> properties:
> compatible:
> - const: nvidia,tegra124-mc
> + enum:
> + - nvidia,tegra114-mc
> + - nvidia,tegra124-mc
>
> reg:
> maxItems: 1
> @@ -64,29 +66,10 @@ patternProperties:
>
> nvidia,emem-configuration:
> $ref: /schemas/types.yaml#/definitions/uint32-array
> - description: |
> + description:
> Values to be written to the EMEM register block. See section
> - "15.6.1 MC Registers" in the TRM.
> - items:
> - - description: MC_EMEM_ARB_CFG
> - - description: MC_EMEM_ARB_OUTSTANDING_REQ
> - - description: MC_EMEM_ARB_TIMING_RCD
> - - description: MC_EMEM_ARB_TIMING_RP
> - - description: MC_EMEM_ARB_TIMING_RC
> - - description: MC_EMEM_ARB_TIMING_RAS
> - - description: MC_EMEM_ARB_TIMING_FAW
> - - description: MC_EMEM_ARB_TIMING_RRD
> - - description: MC_EMEM_ARB_TIMING_RAP2PRE
> - - description: MC_EMEM_ARB_TIMING_WAP2PRE
> - - description: MC_EMEM_ARB_TIMING_R2R
> - - description: MC_EMEM_ARB_TIMING_W2W
> - - description: MC_EMEM_ARB_TIMING_R2W
> - - description: MC_EMEM_ARB_TIMING_W2R
> - - description: MC_EMEM_ARB_DA_TURNS
> - - description: MC_EMEM_ARB_DA_COVERS
> - - description: MC_EMEM_ARB_MISC0
> - - description: MC_EMEM_ARB_MISC1
> - - description: MC_EMEM_ARB_RING1_THROTTLE
> + "20.11.1 MC Registers" in the Tegea114 TRM or
> + "15.6.1 MC Registers" in the Tegra124 TRM.
>
> required:
> - clock-frequency
> @@ -109,6 +92,74 @@ required:
> - "#iommu-cells"
> - "#interconnect-cells"
>
> +allOf:
> + - if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - nvidia,tegra114-mc
> + then:
> + patternProperties:
> + "^emc-timings-[0-9]+$":
> + patternProperties:
> + "^timing-[0-9]+$":
> + properties:
> + nvidia,emem-configuration:
> + items:
> + - description: MC_EMEM_ARB_CFG
> + - description: MC_EMEM_ARB_OUTSTANDING_REQ
> + - description: MC_EMEM_ARB_TIMING_RCD
> + - description: MC_EMEM_ARB_TIMING_RP
> + - description: MC_EMEM_ARB_TIMING_RC
> + - description: MC_EMEM_ARB_TIMING_RAS
> + - description: MC_EMEM_ARB_TIMING_FAW
> + - description: MC_EMEM_ARB_TIMING_RRD
> + - description: MC_EMEM_ARB_TIMING_RAP2PRE
> + - description: MC_EMEM_ARB_TIMING_WAP2PRE
> + - description: MC_EMEM_ARB_TIMING_R2R
> + - description: MC_EMEM_ARB_TIMING_W2W
> + - description: MC_EMEM_ARB_TIMING_R2W
> + - description: MC_EMEM_ARB_TIMING_W2R
> + - description: MC_EMEM_ARB_DA_TURNS
> + - description: MC_EMEM_ARB_DA_COVERS
> + - description: MC_EMEM_ARB_MISC0
> + - description: MC_EMEM_ARB_RING1_THROTTLE

Like I said before, I don't think it is worth enumerating the list of
registers for every variant. If you want to define the length
(minItems/maxItems), then that is fine.

Rob