Re: [RFC PATCH 01/11] dt-bindings: media: qcom,sm8550-iris: Add vpu sub nodes

[Dmitry Baryshkov]

On Thu, Jul 09, 2026 at 06:05:47PM +0530, Vikash Garodia wrote:
> VPU hardwares have a limitation where VPU streams are associated with
> dedicated addressable address range, as illustrated below
> 
>     +-----------------------------------------------------------+
>     | Stream A reserved region (600 MB)                         |
>     | 0x00000000 - 0x25800000                                   |
>     +-----------------------------------------------------------+
>     | Stream B reserved region (3.5 GB)                         |
>     | 0x00000000 - 0xe0000000                                   |
>     +-----------------------------------------------------------+
>     | Other reserved regions                                    |
>     +-----------------------------------------------------------+
> 
> Mapping a stream outside its expected range can cause unintended
> behavior, including device crashes, as reported at:
> https://gitlab.freedesktop.org/drm/msm/-/work_items/100
> 
> To address this limitation, the subset of stream/s are now represented as
> sub nodes, so that they can be associated to the respective addressable
> range.
> The limitation could be exposed when running usecase like concurrent
> video sessions. The binding have been validated with higher concurrent
> sessions across the SOCs supported under this schema.
> 
> Co-developed-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> Signed-off-by: Vikash Garodia <vikash.garodia@xxxxxxxxxxxxxxxx>
> ---
>  .../bindings/media/qcom,sm8550-iris.yaml           | 66 +++++++++++++++++++++-
>  1 file changed, 63 insertions(+), 3 deletions(-)
> 
> +
> +  firmware:

Venus devices have been using 'video-firmware' here. Can we please use
that name? Or I'd ask differently: what is the reason for deviating from
the name that has already been used?

> +    type: object
> +    description:
> +      Firmware context bank represents the firmware processing domain of the VPU. Required to boot
> +      VPU when no hypervisor is present.
> +    properties:
> +      iommus:
> +        maxItems: 1
> +    required:
> +      - iommus
> +    additionalProperties: false
> +

-- 
With best wishes
Dmitry