Re: [PATCH v3 1/5] dt-bindings: bus: add documentation for the IMX AIPSTZ bridge
From: Marco Felsch
Date: Wed Mar 26 2025 - 06:29:24 EST
Hi Laurentiu,
On 25-03-24, Rob Herring wrote:
> On Mon, Mar 24, 2025 at 12:25:52PM -0400, Laurentiu Mihalcea wrote:
> > From: Laurentiu Mihalcea <laurentiu.mihalcea@xxxxxxx>
> >
> > Add documentation for IMX AIPSTZ bridge.
> >
> > Co-developed-by: Daniel Baluta <daniel.baluta@xxxxxxx>
> > Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>
> > Signed-off-by: Laurentiu Mihalcea <laurentiu.mihalcea@xxxxxxx>
> > ---
> > .../bindings/bus/fsl,imx8mp-aipstz.yaml | 107 ++++++++++++++++++
> > 1 file changed, 107 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/bus/fsl,imx8mp-aipstz.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/bus/fsl,imx8mp-aipstz.yaml b/Documentation/devicetree/bindings/bus/fsl,imx8mp-aipstz.yaml
> > new file mode 100644
> > index 000000000000..c0427dfcdaca
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/bus/fsl,imx8mp-aipstz.yaml
> > @@ -0,0 +1,107 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/bus/fsl,imx8mp-aipstz.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Secure AHB to IP Slave bus (AIPSTZ) bridge
> > +
> > +description:
> > + The secure AIPS bridge (AIPSTZ) acts as a bridge for AHB masters
> > + issuing transactions to IP Slave peripherals. Additionally, this module
> > + offers access control configurations meant to restrict which peripherals
> > + a master can access.
>
> Wrap at 80 chars.
>
> > +
> > +maintainers:
> > + - Laurentiu Mihalcea <laurentiu.mihalcea@xxxxxxx>
> > +
> > +properties:
> > + compatible:
> > + const: fsl,imx8mp-aipstz
> > +
> > + reg:
> > + maxItems: 2
> > +
> > + reg-names:
> > + items:
> > + - const: bus
> > + - const: ac
> > +
> > + power-domains:
> > + maxItems: 1
> > +
> > + "#address-cells":
> > + const: 1
> > +
> > + "#size-cells":
> > + const: 1
> > +
> > + "#access-controller-cells":
> > + const: 0
>
> With 0 cells, how do you identify which device it is?
>
> > +
> > + ranges: true
> > +
> > +# borrowed from simple-bus.yaml, no additional requirements for children
> > +patternProperties:
> > + "@(0|[1-9a-f][0-9a-f]*)$":
> > + type: object
> > + additionalProperties: true
> > + properties:
> > + reg:
> > + items:
> > + minItems: 2
> > + maxItems: 4
> > + minItems: 1
> > + maxItems: 1024
> > + ranges:
> > + oneOf:
> > + - items:
> > + minItems: 3
> > + maxItems: 7
> > + minItems: 1
> > + maxItems: 1024
> > + - $ref: /schemas/types.yaml#/definitions/flag
> > + anyOf:
> > + - required:
> > + - reg
> > + - required:
> > + - ranges
> > +
> > +required:
> > + - compatible
> > + - reg
> > + - reg-names
> > + - power-domains
> > + - "#address-cells"
> > + - "#size-cells"
> > + - "#access-controller-cells"
> > + - ranges
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > + - |
> > + #include <dt-bindings/clock/imx8mp-clock.h>
> > + #include <dt-bindings/interrupt-controller/arm-gic.h>
> > +
> > + bus@30c00000 {
> > + compatible = "fsl,imx8mp-aipstz";
> > + reg = <0x30c00000 0x400000>, <0x30df0000 0x10000>;
>
> It doesn't look like you have any registers in the 1st entry, but they
> are child devices? Then you should use ranges and drop it here:
>
> ranges = <0x0 0x30c00000 0x400000>;
>
>
> > + reg-names = "bus", "ac";
Thanks for picking up my suggestion :) IMHO it does look more logical
now. I wasn't aware of the 'ranges' property else I would have suggested
you to use this property instead of having two regs, sorry. Once you
changed it to ranges we can drop the 'reg-names' as well since you only
need to supply the 'ac' register space.
Regards,
Marco
> > + power-domains = <&pgc_audio>;
> > + #address-cells = <1>;
> > + #size-cells = <1>;
> > + #access-controller-cells = <0>;
> > + ranges;
> > +
> > + dma-controller@30e00000 {
> > + compatible = "fsl,imx8mp-sdma", "fsl,imx8mq-sdma";
> > + reg = <0x30e00000 0x10000>;
> > + #dma-cells = <3>;
> > + clocks = <&audio_blk_ctrl IMX8MP_CLK_AUDIOMIX_SDMA3_ROOT>,
> > + <&clk IMX8MP_CLK_AUDIO_ROOT>;
> > + clock-names = "ipg", "ahb";
> > + interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
> > + fsl,sdma-ram-script-name = "imx/sdma/sdma-imx7d.bin";
>
> No 'access-controllers' here?
>
> > + };
> > + };
> > --
> > 2.34.1
> >
>