Re: [PATCH v4 3/5] dt-bindings: bus: Add STM32 ETZPC firewall controller

From: Rob Herring
Date: Mon Jul 13 2020 - 13:05:47 EST


On Wed, Jul 01, 2020 at 03:25:21PM +0200, Benjamin Gaignard wrote:
> Document STM32 ETZPC firewall controller bindings
>
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxx>
> ---
> .../bindings/bus/stm32/st,stm32-etzpc.yaml | 46 ++++++++++++++++++++++
> 1 file changed, 46 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/bus/stm32/st,stm32-etzpc.yaml
>
> diff --git a/Documentation/devicetree/bindings/bus/stm32/st,stm32-etzpc.yaml b/Documentation/devicetree/bindings/bus/stm32/st,stm32-etzpc.yaml
> new file mode 100644
> index 000000000000..d92865fda40c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/bus/stm32/st,stm32-etzpc.yaml
> @@ -0,0 +1,46 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/bus/stm32/st,stm32-etzpc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: STM32 Extended TrustZone Protection controller
> +
> +maintainers:
> + - Benjamin Gaignard <benjamin.gaignard@xxxxxx>
> +
> +description: STMicroelectronics's STM32 firewall bus controller implementation
> +
> +allOf:
> + - $ref: "firewall-provider.yaml#"
> + - $ref: /schemas/simple-bus.yaml#

Your bus has controls/setup, it's not a simple-bus.

Do you expect an old kernel or one with support for "st,stm32-etzpc-bus"
disabled to work? How's it going to know if certain nodes can't be
accessed without that support?

> +
> +properties:
> + compatible:
> + contains:
> + enum:
> + - st,stm32-etzpc-bus
> +
> + reg:
> + maxItems: 1
> +
> + '#firewall-cells':
> + const: 2
> +
> +required:
> + - compatible
> + - reg
> + - '#firewall-cells'
> +
> +examples:
> + - |
> + soc@5c007000 {
> + compatible = "st,stm32-etzpc-bus", "simple-bus";
> + reg = <0x5c007000 0x400>;
> + #firewall-cells = <2>;
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges;
> + };
> +
> +...
> --
> 2.15.0
>