Re: [PATCH v3 02/12] dt-bindings: media: qcom,glymur-iris: Add glymur video codec

Vishnu Reddy
2026-04-28T09:12:47Z

On 4/28/2026 1:58 PM, Krzysztof Kozlowski wrote:
> On 28/04/2026 10:08, Vishnu Reddy wrote:
>> On 4/28/2026 11:44 AM, Krzysztof Kozlowski wrote:
>>> On Tue, Apr 28, 2026 at 09:24:08AM +0530, Vishnu Reddy wrote:
>>>> Add device tree binding for the Qualcomm Glymur Iris video codec. Glymur
>>>> is a new generation of video IP that introduces a dual-core architecture.
>>>> The second core brings its own power domain, clocks, and reset lines,
>>>> requiring additional power domains and clocks in the power sequence.
>>>>
>>>> To accommodate glymur clock and power resources requirement, the maxItems
>>>> constraints in qcom,venus-common.yaml are relaxed. This allows the glymur
>>> This is a very confusing part of commit msg. You cannot relax the
>>> constraints. Each device MUST have a specific, fixed constraint. It is
>>> your task to be sure they are not relaxed.
>>>
>>>
>>>> binding to inherit from the common venus schema without duplicating shared
>>>> properties.
>>> That's obvious. Why would new iris device schema not use common venus
>>> schema? What is different here then that such possibility exists?
>> Glymur platform has a dual-core video codec architecture (vcodec0 + vcodec1),
>> requiring 9 clocks and 5 power domains. The stricter maxItems from the
>> qcom,venus-common.yaml takes precedence, making it impossible to accommodate
>> glymur requirements without updating the common schema.
> But so does every other device, no? So what is different here?

The difference is in the resource count relative to what qcom,venus-common.yaml
permits. Existing platforms like SM8750 have 6 clocks and 4 power domains,
which fall within the maxItems limits defined in the common schema (clocks: 7,
power domains: 4). So for those platforms, referencing qcom,venus-common.yaml
via allOf works fine, their resource counts are within range.

Glymur dual core architecture (vcodec0 + vcodec1) requires 9 clocks and 5 power
domains, both of which exceed the common schema maxItems. Even if
qcom,glymur-iris.yaml explicitly defines maxItems: 9 for clocks and maxItems: 5
for power domains, the stricter limit from qcom,venus-common.yaml takes the
precedence, causing schema validation to fail.

Glymur is the first platform where the common schema limits become a hard
blocker, unlike all prior platforms that happened to stay within those limits.

>
> Best regards,
> Krzysztof