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

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

On Mon, Mar 10, 2025 at 11:59:33AM +0000, Sudeep Holla wrote:

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On Mon, Mar 10, 2025 at 10:45:44AM +0000, Peng Fan wrote:

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

On Thu, Feb 20, 2025 at 08:59:18AM +0800, Peng Fan wrote:

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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

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on this effort, please let me know.

Can you point me to the DTS with which you are seeing this issue ?
I am trying to reproduce the issue but so far not successful. I
did move to power-domains for CPUFreq on Juno. IIUC all we

need is

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both cpufreq and performance genpd drivers in the kernel and

then

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GPU using perf genpd fails with probe deferral right ? I need
pointers to reproduce the issue so that I can check if what I have
cooked up as a solution really works.

This is in downstream tree:

https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2F
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we are using "power-domains" property for cpu perf and gpu/vpu

perf.

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If cpufreq.off=1 is set in bootargs, the vpu/gpu driver will defer

probe.

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OK, does the probe of these drivers get called or they don't as the
driver core doesn't allow that ? I just have a dummy driver for mali
on Juno which just does dev_pm_domain_attach_list() in the probe

and

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it seem to succeed even when cpufreq.off=1 is passed. I see
scmi-cpufreq failing with -ENODEV as expected.

I need to follow the code and check if I can somehow reproduce. Also
are you sure this is not with anything in the downstream code ? Also
have you tried this with v6.14-rc* ? Are you sure all the fw_devlink
code is backported in the tree you pointed me which is v6.6-stable ?

I even tried the above branch, but no luck. The above is neither latest
stable version nor pure stable. It has few extra patches backported
though IIUC. Anyways any pointers to enable me to reproduce the
issue would be much appreciated.

I will setup test based latest linux-next and share results. Please wait.

Thanks,
Peng.

--
Regards,
Sudeep