Re: [RFC PATCH 2/3] media: qcom: camss: Add CAMSS Offline Processing Engine driver

[Bryan O'Donoghue]

On 30/03/2026 15:27, johannes.goede@xxxxxxxxxxxxxxxx wrote:
> > That's another reason I bring up CDM again and again. We probably don't want to fix to the wrong format for OPE, introduce the CDM and then find we have to map from one format to another for large and complex data over and over again for each frame or every N frames.
> CDM is a much lower-level API then what is expected from
> a media-controller centric V4L2 driver. Basically the OPE
> driver will export:

My concern is about wrappering one thing inside of another thing and 
then stuffing it again back into CDM and doing the same on the way out.

There are already 50 MMIO writes in the OPE ISR, I don't believe it is 
sustainable to keep adding MMIO into that.

I'm aware of a project in qcom that did something with making the CDM 
format in libcamera and handed that off to kernel, recommend looking 
into that.

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bod