netdev - Re: [net-next,PATCH 3/3] net: phy: realtek: Add property to enable SSC

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: <20251203123430.zq7sjxfwb5kkff7q@skbuf>
Date: Wed, 3 Dec 2025 14:34:30 +0200
From: Vladimir Oltean <vladimir.oltean@....com>
To: "Russell King (Oracle)" <linux@...linux.org.uk>
Cc: Marek Vasut <marek.vasut@...lbox.org>, netdev@...r.kernel.org,
	"David S. Miller" <davem@...emloft.net>,
	Aleksander Jan Bajkowski <olek2@...pl>,
	Andrew Lunn <andrew@...n.ch>, Conor Dooley <conor+dt@...nel.org>,
	Eric Dumazet <edumazet@...gle.com>,
	Florian Fainelli <f.fainelli@...il.com>,
	Heiner Kallweit <hkallweit1@...il.com>,
	Jakub Kicinski <kuba@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Michael Klein <michael@...sekall.de>,
	Paolo Abeni <pabeni@...hat.com>, Rob Herring <robh@...nel.org>,
	devicetree@...r.kernel.org
Subject: Re: [net-next,PATCH 3/3] net: phy: realtek: Add property to enable
 SSC

On Wed, Dec 03, 2025 at 10:18:35AM +0000, Russell King (Oracle) wrote:
> On Sun, Nov 30, 2025 at 01:58:34AM +0100, Marek Vasut wrote:
> > Add support for spread spectrum clocking (SSC) on RTL8211F(D)(I)-CG,
> > RTL8211FS(I)(-VS)-CG, RTL8211FG(I)(-VS)-CG PHYs. The implementation
> > follows EMI improvement application note Rev. 1.2 for these PHYs.
> > 
> > The current implementation enables SSC for both RXC and SYSCLK clock
> > signals. Introduce new DT property 'realtek,ssc-enable' to enable the
> > SSC mode.
> 
> Should there be separate properties for CLKOUT SSC enable and RXC SSC
> enable?

That's what we're trying to work out. I was going to try and give an
example (based on stmmac) why you wouldn't want RXC SSC but you'd still
want CLKOUT SSC, but it doesn't seem to hold water based on your feedback.
Having one device tree property to control both clocks is a bit simpler.