[PATCH 3/3] media: allegro-dvt: Add DT-bindings for the Gen 3 IP

[Yassine Ouaissa]

On 11.05.2025 22:03, Krzysztof Kozlowski wrote:
>On 11/05/2025 16:47, Yassine Ouaissa wrote:
>> Add the device-tree bindings for the allegro-dvt Gen 3 IP decoders, and
>> update the MAINTAINERS file.
>>
>> Signed-off-by: Yassine Ouaissa <yassine.ouaissa at allegrodvt.com>
>> ---
>>  .../bindings/media/allegrodvt,al300-vdec.yaml | 86 +++++++++++++++++++

Hi Kozlowski,

Thanks for the review.
>
>Looks untested so limited review follows.
>
>A nit, subject: drop second/last, redundant "DT bindings". The
>"dt-bindings" prefix is already stating that these are DT bindings.
>See also:
>https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18
>
I'll fix this issue in the next version.

>>  MAINTAINERS                                   |  1 +
>>  2 files changed, 87 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/media/allegrodvt,al300-vdec.yaml
>>
>
>Please organize the patch documenting compatible (DT bindings) before
>their user.
>See also:
>https://elixir.bootlin.com/linux/v6.14-rc6/source/Documentation/devicetree/bindings/submitting-patches.rst#L46
>

I'll fix this issue in the next version.

>> diff --git a/Documentation/devicetree/bindings/media/allegrodvt,al300-vdec.yaml b/Documentation/devicetree/bindings/media/allegrodvt,al300-vdec.yaml
>> new file mode 100644
>> index 000000000000..ea4a55de570c
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/media/allegrodvt,al300-vdec.yaml
>> @@ -0,0 +1,86 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/media/allegrodvt,al300-vdec.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Allegro DVT Video IP Decoder Gen 3
>> +
>> +maintainers:
>> +  - Yassine OUAISSA <yassine.ouaissa at allegrodvt.com>
>> +
>> +description: |-
>> +  The al300-vdec represents the latest generation of Allegro DVT IP decoding technology, offering
>
>Wrap at 80, see Linux coding style.
>
issue fixed also, thanks.
>> +  significant advancements over its predecessors. This new decoder features
>> +  enhanced processing capabilities with improved throughput and reduced latency.
>> +
>> +  Communication between the host driver software and the MCU is implemented through
>> +  a specialized mailbox interface mechanism. This mailbox system provides a
>> +  structured channel for exchanging commands, parameters, and status information
>> +  between the host CPU and the MCU controlling the codec engines.
>> +
>> +properties:
>> +  compatible:
>> +    const: allegrodvt,al300-vdec
>
>Undocumented prefix.
>
>What is the actual device name? al300? Can you have al300-adec? or
>al300-dec?
>
>

the device name is al300, the vdec is for decoder driver.

>> +
>> +  reg:
>> +    items:
>> +      - description: The registers
>> +      - description: the MCU APB register
>> +
>> +  reg-names:
>> +    items:
>> +      - const: regs
>> +      - const: apb
>> +
>> +  interrupts:
>> +    maxItems: 1
>> +
>> +  clocks:
>> +    items:
>> +      - description: MCU clock
>> +
>> +  clock-names:
>> +    items:
>> +      - const: mcu_clk
>
>Drop clock-names, pretty obvious
>
the clock-name is a require item, it used by the driver.
>> +
>> +  memory-region:
>> +    items:
>> +      - description: Used to allocate memory for the MCU firmware,
>> +      and is also used for various operational buffers required by the MCU during codec operations.
>> +
>> +  firmware-name:
>> +    $ref: /schemas/types.yaml#/definitions/string
>
>Drop, type is already fixed.
>
>missing maxItems: 1
>

The next version will have the maxItem, and drop the ref type.

>> +    description:
>> +      If present, name of the file within the firmware search path containing
>> +      the MCU firmware.
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - reg-names
>> +  - interrupts
>> +  - clocks
>> +  - clock-names
>> +
>> +additionalProperties: False
>> +
>> +examples:
>> +  - |
>> +    axi {
>> +        #address-cells = <2>;
>> +        #size-cells = <2>;
>> +
>> +        ald300: ald300 at a0120000 {
>
>Drop unused label.
>
>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 = "allegrodvt,al300-vdec";
>> +            reg = <0 0xa0120000 0 0x80000>,
>
>Here 0 is not hex
>
>> +            <0x01 0x8000000 0x00 0x8000000>;
>
>but here is hex?
>
>Also misaligned.
>
>Also: very odd large address space.
>

Nice catch, the misaligned issue is fixed.
>>
>
>
>Best regards,
>Krzysztof

Best regards
Yassine OUAISSA