Re: [PATCH v3 0/5] Introduce "non-pixel" sub node within iris video node

Konrad Dybcio
2025-10-09T12:37:03Z

On 10/9/25 7:23 AM, Charan Teja Kalla wrote:
>
>
> On 10/9/2025 6:02 AM, Krzysztof Kozlowski wrote:
>>> If it is legitimate meta-data for the SMMU setup then why _shouldn't_ it
>>> go into the DT ?
>>>
>> We talked about this two or three months ago. I don't understand why you
>> just ignored that entire part and come with new binding just to not
>> touch iommu code. List of entries in iommu must have strict order, just
>> like for every other list, and you should rely on that.
> Hi Krzysztof,
>
> I want to understand a bit more about the statement -- "List of entries
> in iommu must have strict order."
>
> per my understanding:
> iommus = <&apps_smmu sid1 mask1>, <&apps_smmu sid2 mask2>;
>
> and
>
> iommus = <&apps_smmu sid2 mask2>, <&apps_smmu sid1 mask1>;
>
> The end result is same with no breakage as they still end up in using
> the same translation unit, i.e., ordering doesn't matter.
>
> May be you imply something else(may be ABI[1]) here about the order,
> which I am unable to catch...

Krzysztof is referring to the 'items:' blocks in dt-bindings always
containing an ordered list of entries (i.e. the examples you gave
are NOT identical from the bindings perspective even if Linux
happens to treat them in the same way as of right now)

Konrad