Re: [PATCH RFC 1/2] dt-bindings: mailbox: qcom: Document qcom,tmelite-qmp

From: Krzysztof Kozlowski
Date: Thu Dec 05 2024 - 03:12:40 EST


On 05/12/2024 09:06, Sricharan R wrote:
> From: Sricharan Ramabadhran <quic_srichara@xxxxxxxxxxx>
>
> This binding describes the component responsible for communication
> between the TME-L server based subsystems (Q6) and the TME-L client
> (APPSS/BTSS/AUDIOSS), used for security services like secure image
> authentication, enable/disable efuses, crypto services. Each client
> in the SoC has its own block of message RAM and IRQ for communication
> with the TME-L SS. The protocol used to communicate in the message RAM
> is known as Qualcomm Messaging Protocol (QMP).

This is RFC, so only limited review follows. I will review more once
this is ready for review.

>
> Signed-off-by: Sricharan Ramabadhran <quic_srichara@xxxxxxxxxxx>
> ---
> .../bindings/mailbox/qcom,tmelite-qmp.yaml | 70 +++++++++++++++++++
> 1 file changed, 70 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mailbox/qcom,tmelite-qmp.yaml
>
> diff --git a/Documentation/devicetree/bindings/mailbox/qcom,tmelite-qmp.yaml b/Documentation/devicetree/bindings/mailbox/qcom,tmelite-qmp.yaml
> new file mode 100644
> index 000000000000..1f2b3e02b894
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mailbox/qcom,tmelite-qmp.yaml
> @@ -0,0 +1,70 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mailbox/qcom,tmelite-qmp.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm TMELITE IPCC channel
> +
> +maintainers:
> + - Sricharan Ramabadhran <quic_srichara@xxxxxxxxxxx>
> +
> +description:
> + This binding describes the component responsible for communication


Describe the hardware, not the binding.

> + between the TME-L server based subsystems (Q6) and the TME-L client
> + (APPSS/BTSS/AUDIOSS), used for security services like secure image
> + authentication, enable/disable efuses, crypto services. Each client
> + in the SoC has its own block of message RAM and IRQ for communication
> + with the TME-L SS. The protocol used to communicate in the message RAM
> + is known as Qualcomm Messaging Protocol (QMP).
> +
> +properties:
> + compatible:
> + items:
> + - enum:
> + - qcom,ipq5424-tmelite-qmp
> + - const: qcom,tmelite-qmp

Drop generic compatible.


> +
> + reg:
> + maxItems: 1
> + description:
> + The base address and size of the message RAM for this client's
> + communication with the TMELITE core

Drop obvious description. Same everywhere else.

> +
> + interrupts:
> + maxItems: 1
> + description:
> + Should specify the TMELITE message IRQ for this client
> +
> + mboxes:
> + maxItems: 1
> + description:
> + Reference to the mailbox representing the outgoing doorbell in APCS for
> + this client, as described in mailbox/mailbox.txt
> +
> + "#mbox-cells":
> + const: 2
> + description:
> + The first cell is the client-id, and the second cell is the signal-id.

I guess that's the only description not stating obvious.

> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> + - mboxes
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/interrupt-controller/arm-gic.h>
> +
> + tmel_qmp: qmp@32090000 {

Node names should be generic. See also an explanation and list of
examples (not exhaustive) in DT specification:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation


> + compatible = "qcom,ipq5424-tmelite-qmp", "qcom,tmelite-qmp";

Use 4 spaces for example indentation.

> + reg = <0x32090000 0x2000>;
> +...


Best regards,
Krzysztof