Re: [PATCH v2 6/8] dt-bindings: reserved-memory: Add secure CMA reserved memory range

Krzysztof Kozlowski
2023-11-11T12:49:01Z

On 11/11/2023 12:15, Yong Wu wrote:
> Add a binding for describing the secure CMA reserved memory range. The
> memory range also will be defined in the TEE firmware. It means the TEE
> will be configured with the same address/size that is being set in this
> DT node.
>
> Signed-off-by: Yong Wu <yong.wu@mediatek.com>
> ---

What was the outcome of previous discussion? I don't see any references
to the conclusion and your changelog "Reword the dt-binding description"
is way too generic.

You must explain what happened here.

> .../reserved-memory/secure_cma_region.yaml | 44 +++++++++++++++++++
> 1 file changed, 44 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/reserved-memory/secure_cma_region.yaml
>
> diff --git a/Documentation/devicetree/bindings/reserved-memory/secure_cma_region.yaml b/Documentation/devicetree/bindings/reserved-memory/secure_cma_region.yaml
> new file mode 100644
> index 000000000000..8ab559595fbe
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/reserved-memory/secure_cma_region.yaml
> @@ -0,0 +1,44 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/reserved-memory/secure_cma_region.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Secure Reserved CMA Region
> +
> +description:
> + This binding describes a CMA region that can dynamically transition

Describe the hardware or firmware, not the binding. Drop first four
words and rephrase it.

> +between secure and non-secure states that a TEE can allocate memory
> +from.

It does not look like you tested the bindings, at least after quick
look. Please run `make dt_binding_check` (see
Documentation/devicetree/bindings/writing-schema.rst for instructions).
Maybe you need to update your dtschema and yamllint.

Do not send untested code.

> +
> +maintainers:
> + - Yong Wu <yong.wu@mediatek.com>
> +
> +allOf:
> + - $ref: reserved-memory.yaml
> +
> +properties:
> + compatible:
> + const: secure_cma_region

Still wrong compatible. Look at other bindings - there is nowhere
underscore. Look at other reserved memory bindings especially.

Also, CMA is a Linux thingy, so either not suitable for bindings at all,
or you need Linux specific compatible. I don't quite get why do you even
put CMA there - adding Linux specific stuff will get obvious pushback...

> +
> +required:
> + - compatible
> + - reg
> + - reusable
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> +

Stray blank line.

> + reserved-memory {
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges;
> +
> + reserved-memory@80000000 {
> + compatible = "secure_cma_region";
> + reusable;
> + reg = <0x80000000 0x18000000>;

reg is second property. Open DTS and check how it is there.

> + };
> + };

Best regards,
Krzysztof