linux-kernel - Re: [PATCH v2 1/4] firmware: arm_scmi: Bypass setting fwnode for scmi cpufreq

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <e20415aa-517c-4e72-a1c3-9c02769c1149@stanley.mountain>
Date: Thu, 6 Feb 2025 14:31:19 +0300
From: Dan Carpenter <dan.carpenter@...aro.org>
To: Peng Fan <peng.fan@....nxp.com>
Cc: Sudeep Holla <sudeep.holla@....com>,
	Cristian Marussi <cristian.marussi@....com>,
	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 v2 1/4] firmware: arm_scmi: Bypass setting fwnode for
 scmi cpufreq

On Thu, Feb 06, 2025 at 06:52:20PM +0800, Peng Fan wrote:
> On Wed, Feb 05, 2025 at 03:45:00PM +0300, Dan Carpenter wrote:
> >On Mon, Jan 20, 2025 at 03:13:29PM +0800, Peng Fan (OSS) wrote:
> >> diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
> >> index 2c853c84b58f530898057e4ab274ba76070de05e..7850eb7710f499888d32aebf5d99df63db8bfa26 100644
> >> --- a/drivers/firmware/arm_scmi/bus.c
> >> +++ b/drivers/firmware/arm_scmi/bus.c
> >> @@ -344,6 +344,21 @@ static void __scmi_device_destroy(struct scmi_device *scmi_dev)
> >>  	device_unregister(&scmi_dev->dev);
> >>  }
> >>  
> >> +static int
> >> +__scmi_device_set_node(struct scmi_device *scmi_dev, struct device_node *np,
> >> +		       int protocol, const char *name)
> >> +{
> >> +	/* cpufreq device does not need to be supplier from devlink perspective */
> >> +	if ((protocol == SCMI_PROTOCOL_PERF) && !strcmp(name, "cpufreq")) {
> >
> >I don't love this...  It seems like an hack.  Could we put a flag
> >somewhere instead?  Perhaps in scmi_device?  (I'm just saying that
> >because that's what we're passing to this function).
> 
> This means when creating scmi_device, a flag needs to be set which requires
> to extend scmi_device_id to include a flag entry or else.
> 
> As below in scmi-cpufreq.c
> { SCMI_PROTOCOL_PERF, "cpufreq", SCMI_FWNODE_NO }
> 

Yeah, I like that.

-	if ((protocol == SCMI_PROTOCOL_PERF) && !strcmp(name, "cpufreq")) {
+	if (scmi_dev->flags & SCMI_FWNODE_NO) {

Or we could do something like "if (scmi_dev->no_fwnode) {"

regards,
dan carpenter