Re: [PATCH v3 1/2] dt-bindings: soc: qcom: Add qcom,kaanapali-imem compatible
From: Bjorn Andersson
Date: Thu Nov 06 2025 - 15:20:47 EST
On Tue, Nov 04, 2025 at 03:58:27PM +0100, Konrad Dybcio wrote:
> On 11/4/25 3:52 PM, Krzysztof Kozlowski wrote:
> > On 04/11/2025 15:38, Konrad Dybcio wrote:
> >> On 11/4/25 3:37 PM, Krzysztof Kozlowski wrote:
> >>> On 04/11/2025 15:35, Konrad Dybcio wrote:
> >>>> On 11/4/25 3:26 PM, Krzysztof Kozlowski wrote:
> >>>>> This I got, but nothing here explains why you need generic compatible.
> >>>>> To re-iterate: there was no generic compatible before, now there is.
> >>>>> Writing bindings and numerous reviews from DT maintainers ask not to use
> >>>>> generic compatibles.
> >>>>
> >>>> OK so let's not worry about a generic compatible. IMEM exists since
> >>>> MSM8974 and it only had major hw updates with SM8550. They don't
> >>>> impact the software interface though, so qcom,msm8974-imem is OK.
> >>>>
> >>>> There's a separate control/status register address space for each
> >>>> instance of this IP (usually far apart from the actual SRAM pool),
> >>>> which Linux doesn't have to care about.
> >>>
> >>> Just use qcom,kaanapali-imem - that's the first device here without syscons.
> >>
> >> So we don't want to move the existing ones over?
> >
> > This was never discussed and this patch did not do it. You cannot move
> > them, that's ABI.
>
> I see, I implicitly assumed this would be a sweeping change.
>
> So should the Kaanapali submitters simply send a version of this
> patch with:
>
> - oneOf:
> - const: qcom,kaanapali-imem
> - items:
> # existing big list
>
> ?
We have 33 cases of "this is just a generic Qualcomm IMEM block", could
we just make it "qcom,imem" until there's actually a sign that it's not
a platform-independent block?
Regards,
Bjorn
>
> I'm not a huge fan of using kaanapali as the fallback-going-forward
> since it's literally the newest platform on the shelves (or perhaps
> not even on the shelves yet..) so it's going to look funny when
> someone comes up with support for another 2013 soc.. but perhaps
> that's just how things are supposed to be
>
> Konrad