linux-kernel - RE: [PATCH v4 5/5] clk: scmi: Support Spread Spectrum for NXP i.MX95

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:
 <PAXPR04MB84590D5AAAB56ED7E1CBDE05881CA@PAXPR04MB8459.eurprd04.prod.outlook.com>
Date: Wed, 24 Sep 2025 11:43:56 +0000
From: Peng Fan <peng.fan@....com>
To: Sebin Francis <sebin.francis@...com>, Michael Turquette
	<mturquette@...libre.com>, Stephen Boyd <sboyd@...nel.org>, Sudeep Holla
	<sudeep.holla@....com>, Cristian Marussi <cristian.marussi@....com>, Marco
 Felsch <m.felsch@...gutronix.de>, Rob Herring <robh@...nel.org>, Krzysztof
 Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>, Brian
 Masney <bmasney@...hat.com>
CC: Dan Carpenter <dan.carpenter@...aro.org>, Geert Uytterhoeven
	<geert@...ux-m68k.org>, "linux-clk@...r.kernel.org"
	<linux-clk@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "arm-scmi@...r.kernel.org"
	<arm-scmi@...r.kernel.org>, "linux-arm-kernel@...ts.infradead.org"
	<linux-arm-kernel@...ts.infradead.org>, "devicetree@...r.kernel.org"
	<devicetree@...r.kernel.org>
Subject: RE: [PATCH v4 5/5] clk: scmi: Support Spread Spectrum for NXP i.MX95

> Subject: Re: [PATCH v4 5/5] clk: scmi: Support Spread Spectrum for
> NXP i.MX95
...
> >>>        SCMI_CLOCK_CFG_OEM_START = 0x80,
> >>> +     SCMI_CLOCK_CFG_IMX_SSC = 0x80,
> >>
> >> TI is also planning to implement the same in our upcoming platform.
> >> so can we use a generic ID instead of vender specfic message ID?
> >
> > I tried to push to new generic ID [1] in half a year ago, but in the
> > end ARM decided not to add generic ID for spread spectrum support.
> >
> > To i.MX, it is too late to use a generic ID and waiting spec, i.MX
> > firmware has been public for quite some time and passed several
> external releases.
> > So I need to use what our firmware adds and spec allows: vendor
> > extension.
> 
> Thanks for the quick response,
> Since this implementation is specific to i.MX, can you move this to a
> vendor specific file, so that it will not break i.MX's firmware and TI can
> implement SSC in TI specific file.

i.MX has encountered issue with pinctrl-scmi.c and pinctrl-imx-scmi.c
both supports SCMI PINCTRL. Current linux scmi does not support
both drivers built in kernel image, because scmi devlink issue.

Sudeep said he would address the devlink issue in 6.19 cycle.

Given the current situation, I'm hesitant to introduce a new driver
saying clk-imx-scmi.c.

What I'm unclear about is whether moving to a vendor-specific file
implies creating a new driver (i.e., clk-imx-scmi.c), or if it could be
handled via a callback or another mechanism. Could you help
clarify the intended direction?

Sudeep, Cristian

Would you please jump in and say something?

Thanks,
Peng.

> 
> >
> > [1]
> >
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2F
> lore
> > .kernel.org%2Farm-
> scmi%2FZ8iKErarE0lHWxEy%40pluto%2F&data=05%7C02%7Cpe
> >
> ng.fan%40nxp.com%7C4bd4c6b93ff146fbfc4c08ddfb4c5ab5%7C686ea
> 1d3bc2b4c6f
> >
> a92cd99c5c301635%7C0%7C0%7C638943027585856649%7CUnknow
> n%7CTWFpbGZsb3d8
> >
> eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiI
> sIkFOIjoiTW
> >
> FpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=zEREeXuiaC5wWS
> C%2FUAIe6wfiTf
> > MG5AEY5vZ7D4OEIGI%3D&reserved=0
> >
> > Regards,
> > Peng.
> 
> Thanks
> Sebin