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

[Krzysztof Kozlowski <krzk@kernel.org>]

On 18/02/2026 13:26, Konrad Dybcio wrote:
> 
> 
> 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@oss.qualcomm.com>
>>>>>
>>>>> 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.

And that's the problem - I do not see consuming child. I see
of_parse_phandle to sram node, not the child.

> 
> 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

Best regards,
Krzysztof