Re: [PATCH 1/4] firmware: arm_scmi: bus: Bypass setting fwnode for scmi cpufreq

Peng Fan
2025-02-20T01:01:37Z

On Wed, Feb 19, 2025 at 10:17:46AM +0000, Sudeep Holla wrote:
>On Tue, Feb 18, 2025 at 09:36:19PM +0800, Peng Fan wrote:
>> On Tue, Feb 18, 2025 at 10:24:52AM +0000, Sudeep Holla wrote:
>> >On Tue, Feb 18, 2025 at 09:09:49AM +0800, Peng Fan wrote:
>> >> A potential solution is not using reg in the protocol nodes. Define nodes
>> >> as below:
>> >> devperf {
>> >> compatible ="arm,scmi-devperf";
>> >> }
>> >>
>> >> cpuperf {
>> >> compatible ="arm,scmi-cpuperf";
>> >> }
>> >>
>> >> pinctrl {
>> >> compatible ="arm,scmi-pinctrl";
>> >> }
>> >>
>> >> The reg is coded in driver.
>> >>
>> >> But the upper requires restruction of scmi framework.
>> >>
>> >> Put the above away, could we first purse a simple way first to address
>> >> the current bug in kernel? Just as I prototyped here:
>> >> https://github.com/MrVan/linux/tree/b4/scmi-fwdevlink-v2
>> >>
>> >
>> >Good luck getting these bindings merged. I don't like it as it is pushing
>> >software policy or issues into to the devicetree. What we have as SCMI
>> >binding is more than required for a firmware interface IMO. So, you are
>>
>> Would you mind share more info on other cases that SCMI not as firmware
>> interface?
>>
>> >on your own to get these bindings approved as I am not on board with
>> >these but if you convince DT maintainers, I will have a look at it then
>> >to see if we can make that work really.
>>
>> The issues are common to SCMI, not i.MX specific.
>> I just propose potential solutions. You are the SCMI maintainer, there
>> is no chance to get bindings approved without you.
>>
>
>I am not blocking you. What I mentioned is I don't agree that DT can be used
>to resolve this issue, but I don't have time or alternate solution ATM. So
>if you propose DT based solution and the maintainers agree for the proposed
>bindings I will take a look and help you to make that work. But I will raise
>any objections I may have if the proposal has issues mainly around the
>compatibility and ease of maintenance.

Sorry, if I misunderstood.

I will give a look on this and propose a RFC.

DT maintainers may ask for a patchset including binding change and
driver changes to get a whole view on the compatible stuff.

BTW, Cristian, Saravana if you have any objections/ideas or would take on this
effort, please let me know.

Thanks,
Peng

>
>> No more ideas from me. Leave this to you in case you have better solution.
>>
>
>Unfortunately no, I don't have one. I haven't had time to sit and explore
>the issue and think of any solution yet.
>
>--
>Regards,
>Sudeep