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

From: Conor Dooley
Date: Tue Oct 04 2022 - 03:33:51 EST


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
>