From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 45665239E7F; Fri, 7 Nov 2025 15:33:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=78.32.30.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762529620; cv=none; b=irEZ31YcHU/iaFyrABY6uPYbjEjBOTRpKCwD4ous/lKvoG+q2Cxt56ahgx+CBAbGshOIgwYIFMUxR7yR8iV3Dy+RCnjuCMHq2GggMorxlDr3t9Kv266WD2CwmeBfZQ+p2PnagXgpI+CkvSClfGhRqGhp5mtExRIcHOq27B2KFpc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762529620; c=relaxed/simple; bh=P3ab668+SgsSZopmzQ6luLdGMiRFYv+zhm5ze83iYCo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=k/t1MM8DarFQf21O7g6DNG6xL0mU/HQzrpnjXnqSdcPfiva2wpaTzv5/T+QKqHCapyABzRmxAT70GuUuTcmbJVmR0Qsu+ohssr9FwBn2aXXfsy7w8dyKx7T3dIpkKqRod6KXmIDg05enapNUYVSImseCp7gAqYP+I3ZtwVazsZQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk; spf=none smtp.mailfrom=armlinux.org.uk; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b=fWkvLxd4; arc=none smtp.client-ip=78.32.30.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="fWkvLxd4" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=HD/Q7fVnxSxfev0yk/VhBnw0ldUa9+lYqYF4QzV4RV4=; b=fWkvLxd49Wjnh2n2/9JPLxpAgH W4EX+IEXmwmxM1+0Yy5nVbc5Yjnd7ibQMKQQ2sMOC0AFZ9vFDDtTulhJ8kN0tm0Y56n8RvyXlQQWG zjH4oYaw47mbN5y7l4fjzbHTCYXzyMm7wDR3QbrAv90Bd5Q0DQJ8oAwSXoG4yUx3Z8qvPfeIKPDh3 D4rckrNiQ2S53gGU82Fc6+RtX4QF5am4NAgvgIo7F0I7O6hwEvTYY0POkoqsgbTVid+Org/zkDWzD L4dnPOs3iHy1dFnUUs5knxxWRQiUuQPwJyiqV27pXJMC7FHmez4BQ09NkWHWBVHJ+ts/8xLfuAm2t jdEJMxoA==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:49970) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vHOSw-000000006pZ-1u8J; Fri, 07 Nov 2025 15:33:30 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.98.2) (envelope-from ) id 1vHOSt-000000007gr-2tdD; Fri, 07 Nov 2025 15:33:27 +0000 Date: Fri, 7 Nov 2025 15:33:27 +0000 From: "Russell King (Oracle)" To: Vladimir Oltean Cc: Andrew Lunn , Jonas Gorski , Florian Fainelli , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Florian Fainelli , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, =?iso-8859-1?Q?=C1lvaro_Fern=E1ndez?= Rojas Subject: Re: [PATCH net v2] net: dsa: b53: bcm531x5: fix cpu rgmii mode interpretation Message-ID: References: <20251107083006.44604-1-jonas.gorski@gmail.com> <20251107144515.ybwcfyppzashtc5c@skbuf> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251107144515.ybwcfyppzashtc5c@skbuf> Sender: Russell King (Oracle) On Fri, Nov 07, 2025 at 04:45:15PM +0200, Vladimir Oltean wrote: > On Fri, Nov 07, 2025 at 03:07:48PM +0100, Andrew Lunn wrote: > > > There is allwinner/sun7i-a20-lamobo-r1.dts, which uses "rgmii-txid", > > > which is untouched by this patch. The ethernet interface uses "rgmii". > > > > Which is odd, but lets leave it alone. > > > > > And there is arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-elbert.dts, > > > where a comment says that it has a BCM53134, but there is no such > > > node. The ethernet node uses "rgmii". > > > > aspeed pretty much always get phy-mode wrong. So i would not worry too > > much about this. > > > > > So one doesn't define one, one uses rgmii-id on the switch / phy side > > > and rgmii on the ethernet mac side, and one only defines the ethernet > > > mac side as rgmii. > > > > That is reasonable. It is a lot less clear what is correct for a > > MAC-MAC connection. For a MAC-PHY connection we do have documentation, > > the preference is that the PHY adds the delays, not the MAC. If the > > switch is playing PHY, then having it add delays is sensible. > > > > > > I would maybe add a dev_warn() here, saying the DT blob is out of date > > > > and needs fixing. And fix all the in kernel .dts files. > > > > > > Sure I can add a warning. > > > > Great, thanks. > > > > Andrew > > +Russell As this is discussing the applicability of RGMII delays for DSA switches, I've long held out that the situation is a mess, and diverges from what we decide to do for MACs - so I'd prefer not to get involved in this, except to say... > Since there is no 'correct' way to apply RGMII delays on a MAC according > to phy-mode, my advice, if possible, would be to leave sleeping dogs lie > and fix broken setups by adding the explicit device tree properties in > the MAC, and adding driver support for parsing these. Indeed - let's not break existing working setups. If there is a problem with them, then that's the time to start thinking about changing them. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!