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

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Message-ID: <Z6uFMW94QNpFxQLK@bogus>
Date: Tue, 11 Feb 2025 17:13:21 +0000
From: Sudeep Holla <sudeep.holla@....com>
To: "Peng Fan (OSS)" <peng.fan@....nxp.com>
Cc: Cristian Marussi <cristian.marussi@....com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Saravana Kannan <saravanak@...gle.com>,
	Linus Walleij <linus.walleij@...aro.org>,
	Dong Aisheng <aisheng.dong@....com>,
	Fabio Estevam <festevam@...il.com>, Shawn Guo <shawnguo@...nel.org>,
	Jacky Bai <ping.bai@....com>,
	Pengutronix Kernel Team <kernel@...gutronix.de>,
	Sascha Hauer <s.hauer@...gutronix.de>, arm-scmi@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	linux-gpio@...r.kernel.org, imx@...ts.linux.dev,
	Peng Fan <peng.fan@....com>
Subject: Re: [PATCH 1/4] firmware: arm_scmi: bus: Bypass setting fwnode for
 scmi cpufreq

On Wed, Dec 25, 2024 at 04:20:44PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@....com>
> 
> Two drivers scmi_cpufreq.c and scmi_perf_domain.c both use
> SCMI_PROTCOL_PERF protocol, but with different name, so two scmi devices
> will be created. But the fwnode->dev could only point to one device.
> 
> If scmi cpufreq device created earlier, the fwnode->dev will point to
> the scmi cpufreq device. Then the fw_devlink will link performance
> domain user device(consumer) to the scmi cpufreq device(supplier).
> But actually the performance domain user device, such as GPU, should use
> the scmi perf device as supplier. Also if 'cpufreq.off=1' in bootargs,
> the GPU driver will defer probe always, because of the scmi cpufreq
> device not ready.
> 
> Because for cpufreq, no need use fw_devlink. So bypass setting fwnode
> for scmi cpufreq device.
>

Not 100% sure if above is correct. See:

Commit 8410e7f3b31e ("cpufreq: scmi: Fix OPP addition failure with a dummy clock provider")

Am I missing something ?

-- 
Regards,
Sudeep