Re: [PATCH net-next v3 1/3] dt-bindings: sram: qcom,imem: Allow modem-tables subnode

[Konrad Dybcio]

On 18-Feb-26 12:56, Krzysztof Kozlowski wrote:
> On 18/02/2026 12:05, Konrad Dybcio wrote:
>> On 2/17/26 9:25 PM, Krzysztof Kozlowski wrote:
>>> On Tue, Feb 17, 2026 at 02:30:31PM +0100, Konrad Dybcio wrote:
>>>> From: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
>>>>
>>>> The IP Accelerator hardware/firmware owns a sizeable region within the
>>>> IMEM, named 'modem-tables', containing various packet processing
>>>> configuration data.
>>>>
>>>> It's not actually accessed by the OS, although we have to IOMMU-map it
>>>> with the IPA device, so that presumably the firmware can act upon it.
>>>>
>>>> Allow it as a subnode of IMEM.
>>>
>>> You do not have compatible, so rely on the node name as ABI, which is
>>> fine in general but... I do not see usage of it in the driver. Why do
>>> you need to define modem-tables child then?
>>
>> I don't really *need* the node name to be an ABI. However, the current
>> binding for IMEM only allows a named "pil-reloc@.." subnode (which is
>> consumed via of_find_compatible_node() in the remoteproc subsystem) so I
>> figured the intention was to keep the list of allowed subnodes strictly
>> moderated
>>
>> If you'd prefer a blanket pattern declaration with say '^[a-z]@[0-9a-z]+$'
>> with just a reg requirement inside, I'm fine with that too
> 
> No, the problem is that you do not use the ABI here at all. Neither
> would you use the blanket pattern, so my question stays: why adding ABI
> which is not used?

The subnode I'm trying to introduce is going to be consumed (via a
phandle reference) from the IPA node, as done by the remaining 2
patches in this series.

I would much prefer not to touch this binding file, but there's an
additionalProperties: false and just adding it as-is results in a:

arch/arm64/boot/dts/qcom/sc7280-idp.dtb: sram@146a5000: 'modem-tables@1234' does not match any of the regexes: '^pil-reloc@[0-9a-f]+$', 'pinctrl-[0-9]+'
        from schema $id: http://devicetree.org/schemas/sram/qcom,imem.yaml#

Konrad

> 
> The pil-reloc is being used, as you pointed out.
> 
> Best regards,
> Krzysztof