Subject: Re: [PATCH 4/8] arm64: dts: qcom: shikra: Add CAMSS node

From: Vikram Sharma <[email-masked]>
Date: Fri, 29 May 2026 20:22:25 +0530

On 5/29/2026 3:51 AM, [email-masked] wrote:
>> +			iommus = <&apps_smmu 0x400 0x0>;
> So I'm suspicious of this IOMMU.
>
> We should list the full range of IFE SIDs here not a subset. Since we are
> register compatible with Agatti that implies to me we should also be IOMMU
> compatible.

Shikra and Agatti are not iommu compatible in terms of Stream ID. Only VFE SID is same
for both. Agatti is documenting iommu for VFE, CDM and OPE. OPE is not yet enabled for
Shikra and in my opinion it should be added as a separate yaml similar to Agatti.
"https://lore.kernel.org/all/[email-masked]/"

Regarding cdm iommu we have excluded it as we do not use it to program registers as of now.

Loic/Bryan, Please share your thoughts on this?

> Please list in your next submission commit log the IOMMU SIDs - comment in
> the DTS is fine too.

Sure.

> Ideally list the IOMMus for Agatti/2290 and then explain why the singleton
> you have enumerated here is the only required one.
>
> Right now my suspicion radar is high that either the Agatti binding is
> wrong or the Shikra binding is.
>
> Possibly both.

Regards,

Vikram