Re: [RFC PATCH v2 1/2] dt-bindings: soc: renesas: r9a07g043f-l2-cache: Add DT binding documentation for L2 cache controller

[Conor Dooley <conor.dooley@xxxxxxxxxxxxx>]

On Mon, Oct 03, 2022 at 11:32:21PM +0100, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> 
> Add DT binding documentation for L2 cache controller found on RZ/Five SoC.
> 
> The Renesas RZ/Five microprocessor includes a RISC-V CPU Core (AX45MP
> Single) from Andes. The AX45MP core has an L2 cache controller, this patch
> describes the L2 cache block.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
>  .../soc/renesas/r9a07g043f-l2-cache.yaml      | 82 +++++++++++++++++++
>  1 file changed, 82 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/soc/renesas/r9a07g043f-l2-cache.yaml
> 
> diff --git a/Documentation/devicetree/bindings/soc/renesas/r9a07g043f-l2-cache.yaml b/Documentation/devicetree/bindings/soc/renesas/r9a07g043f-l2-cache.yaml
> new file mode 100644
> index 000000000000..f96eeffa58ce
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/renesas/r9a07g043f-l2-cache.yaml
> @@ -0,0 +1,82 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +# Copyright (C) 2022 Renesas Electronics Corp.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/soc/renesas/r9a07g043f-l2-cache.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: SiFive L2 Cache Controller
> +
> +maintainers:
> +  - Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> +
> +description:
> +  A level-2 cache (L2C) is used to improve the system performance by providing
> +  a larger amount of cache line entries and reasonable access delays. The L2C
> +  is shared between cores, and a non-inclusive non-exclusive policy is used.
> +
> +properties:
> +  compatible:
> +    items:
> +      - const: andestech,ax45mp-cache
> +      - const: cache

I think preemptively adding a "renesas,r9a07g043f-l2-cache" here is a
good idea, just in case something crops up down the line.

Thanks,
Conor.

> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  cache-line-size:
> +    const: 64
> +
> +  cache-level:
> +    const: 2
> +
> +  cache-sets:
> +    const: 1024
> +
> +  cache-size:
> +    enum: [131072, 262144, 524288, 1048576, 2097152]
> +
> +  cache-unified: true
> +
> +  next-level-cache: true
> +
> +  pma-regions:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    minItems: 1
> +    maxItems: 16
> +    description: Optional array of memory regions to be set as non-cacheable
> +                 bufferable regions which will be setup in the PMA.
> +
> +additionalProperties: false
> +
> +required:
> +  - compatible
> +  - cache-line-size
> +  - cache-level
> +  - cache-sets
> +  - cache-size
> +  - cache-unified
> +  - interrupts
> +  - reg
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    cache-controller@2010000 {
> +        reg = <0x13400000 0x100000>;
> +        compatible = "andestech,ax45mp-cache", "cache";
> +        interrupts = <508 IRQ_TYPE_LEVEL_HIGH>;
> +        cache-line-size = <64>;
> +        cache-level = <2>;
> +        cache-sets = <1024>;
> +        cache-size = <262144>;
> +        cache-unified;
> +        pma-regions = <0x00000000 0x10000000>,
> +                      <0x10000000 0x04000000>,
> +                      <0x20000000 0x10000000>,
> +                      <0x58000000 0x08000000>;
> +    };
> -- 
> 2.25.1
>