Re: [PATCH v2 1/2] dt-bindings: interrupt-controller: mpm: Pass MSG RAM slice through phandle

[Krzysztof Kozlowski]

On 12/04/2023 14:09, Konrad Dybcio wrote:
> 
> 
> On 12.04.2023 13:55, Krzysztof Kozlowski wrote:
>> On 12/04/2023 13:47, Konrad Dybcio wrote:
>>>> For unrelated reasons I actually have some patches for this, that switch
>>>> the /smd top-level node to a "remoteproc-like" node dedicated to the
>>>> RPM, similar to how WCNSS/ADSP/Modem/etc are represented. I need this to
>>>> add additional (optional) properties like "resets" and "iommus" for the
>>>> RPM, but it would allow adding arbitrary subnodes as well:
>>>>
>>>> https://github.com/msm8916-mainline/linux/commit/35231ac28703805daa8220f1233847c7df34589e
>>>>
>>>> I could finish those up and post them if that would help...
>>> Krzysztof, what do you think?
>>
>> I don't know what is there in MSM8916 and how it should be represented.
> Similarly to other Qualcomm SoCs, MSM8916 has a RPM (Cortex-M3) core,
> which communicates over the SMD protocol (or G-LINK on >=8996).
> 
> The Qualcomm firmware loads the RPM fw blob and sets it up early in
> the boot process, but msm8916-mainline folks managed to get TF-A
> going and due to it being less.. invasive.. than the Qualcomm TZ,
> RPM needs a bit more handling to be accessible.
> 
> The M3 core is wired up through the CNoC bus and we communicate
> with it through the MSG RAM and the "APCS mailbox".

Thanks, that's actually good description. Yet I still do not know what
is exactly the problem and the question. Linking some out of tree
commits does not give me the answer, at least I cannot get that answer
form the link.

For example what I don't understand is: why additional resources (like
resets) can be provided only in new binding, but not in the old.

Best regards,
Krzysztof