From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31AAFC43603 for ; Thu, 19 Dec 2019 21:49:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC70024672 for ; Thu, 19 Dec 2019 21:49:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="sInF7qsm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726963AbfLSVth (ORCPT ); Thu, 19 Dec 2019 16:49:37 -0500 Received: from pandora.armlinux.org.uk ([78.32.30.218]:40270 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726866AbfLSVth (ORCPT ); Thu, 19 Dec 2019 16:49:37 -0500 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=AYRcRglwcP5lo6E4Zn08sq4uQ/tRp+N1/Lj/8ULBHuo=; b=sInF7qsmdiLReNyXRT7V8wbck MJKkGXTEe/cg36RETU4RMYa4IIiXV/MFte/uJgpwt+/vA+X9ToXVY7re2GLS8sUpa0mh7tl4bhTe0 Zga6ZEfAByCt8xHuiIMDWUKlHfURgmr4zwn24e4jSxwKL8jWn1ko+H9ZRaDbBmUgwek7+VyjDmtE6 WWhaN6XUfpZf6/GK74JMePirCJUOjx2pbZbRbV9V1wzIMQuXsWZ5WUeU01OhZaxJCxwYGztSTyALr nSfG1nWGJo0qjwpiwpmVUCw/YJXeoGyT5wzeSny3x1IEGNfN9zhB56fj1VTtW1yqJSowzJdueVRPm N2F+K+YuA==; Received: from shell.armlinux.org.uk ([2001:4d48:ad52:3201:5054:ff:fe00:4ec]:43588) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ii3fo-0004xw-LX; Thu, 19 Dec 2019 21:49:32 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1ii3fm-0005ha-Eo; Thu, 19 Dec 2019 21:49:30 +0000 Date: Thu, 19 Dec 2019 21:49:30 +0000 From: Russell King - ARM Linux admin To: "Madalin Bucur (OSS)" Cc: "davem@davemloft.net" , "netdev@vger.kernel.org" , "andrew@lunn.ch" , "f.fainelli@gmail.com" , "hkallweit1@gmail.com" , "shawnguo@kernel.org" , "devicetree@vger.kernel.org" Subject: Re: [PATCH 1/6] net: phy: add interface modes for XFI, SFI Message-ID: <20191219214930.GG25745@shell.armlinux.org.uk> References: <1576768881-24971-1-git-send-email-madalin.bucur@oss.nxp.com> <1576768881-24971-2-git-send-email-madalin.bucur@oss.nxp.com> <20191219172834.GC25745@shell.armlinux.org.uk> <20191219190308.GE25745@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Thu, Dec 19, 2019 at 09:34:57PM +0000, Madalin Bucur (OSS) wrote: > > -----Original Message----- > > From: Russell King - ARM Linux admin > > Sent: Thursday, December 19, 2019 9:03 PM > > To: Madalin Bucur > > Cc: davem@davemloft.net; netdev@vger.kernel.org; andrew@lunn.ch; > > f.fainelli@gmail.com; hkallweit1@gmail.com; shawnguo@kernel.org; > > devicetree@vger.kernel.org > > Subject: Re: [PATCH 1/6] net: phy: add interface modes for XFI, SFI > > > > On Thu, Dec 19, 2019 at 06:32:51PM +0000, Madalin Bucur wrote: > > > > -----Original Message----- > > > > From: Russell King - ARM Linux admin > > > > Sent: Thursday, December 19, 2019 7:29 PM > > > > To: Madalin Bucur > > > > Cc: davem@davemloft.net; netdev@vger.kernel.org; andrew@lunn.ch; > > > > f.fainelli@gmail.com; hkallweit1@gmail.com; shawnguo@kernel.org; > > > > devicetree@vger.kernel.org > > > > Subject: Re: [PATCH 1/6] net: phy: add interface modes for XFI, SFI > > > > > > > > On Thu, Dec 19, 2019 at 05:21:16PM +0200, Madalin Bucur wrote: > > > > > From: Madalin Bucur > > > > > > > > > > Add explicit entries for XFI, SFI to make sure the device > > > > > tree entries for phy-connection-type "xfi" or "sfi" are > > > > > properly parsed and differentiated against the existing > > > > > backplane 10GBASE-KR mode. > > > > > > > > 10GBASE-KR is actually used for XFI and SFI (due to a slight mistake > > on > > > > my part, it should've been just 10GBASE-R). > > > > > > > > Please explain exactly what the difference is between XFI, SFI and > > > > 10GBASE-R. I have not been able to find definitive definitions for > > > > XFI and SFI anywhere, and they appear to be precisely identical to > > > > 10GBASE-R. It seems that it's just a terminology thing, with > > > > different groups wanting to "own" what is essentially exactly the > > > > same interface type. > > > > > > Hi Russell, > > > > > > 10GBase-R could be used as a common nominator but just as well 10G and > > > remove the rest while we're at it. There are/may be differences in > > > features, differences in the way the HW is configured (the most > > > important aspect) and one should be able to determine what interface > > > type is in use to properly configure the HW. SFI does not have the CDR > > > function in the PMD, relying on the PMA signal conditioning vs the XFI > > > that requires this in the PMD. We kept the xgmii compatible for so long > > > without much issues until someone started cleaning up the PHY supported > > > modes. Since we're doing that, let's be rigorous. The 10GBase-KR is > > > important too, we have some backplane code in preparation and having it > > > there could pave the way for a simpler integration. > > > > The problem we currently have is: > > > > $ grep '10gbase-kr' arch/*/boot/dts -r > > > > virtually none of those are actually backplane. For the mcbin matches, > > these are either to a 88x3310 PHY for the doubleshot, which dynamically > > operates between XFI, 5GBASE-R, 2500BASE-X, or SGMII according to the > > datasheet. > > Yes, I've seen it's used already in several places: > > $ grep PHY_INTERFACE_MODE_10GKR drivers/net -nr > drivers/net/phy/marvell10g.c:219: if (iface != PHY_INTERFACE_MODE_10GKR) { > drivers/net/phy/marvell10g.c:307: phydev->interface != PHY_INTERFACE_MODE_10GKR) > drivers/net/phy/marvell10g.c:389: phydev->interface == PHY_INTERFACE_MODE_10GKR) && phydev->link) { > drivers/net/phy/marvell10g.c:398: phydev->interface = PHY_INTERFACE_MODE_10GKR; > drivers/net/phy/phylink.c:296: case PHY_INTERFACE_MODE_10GKR: > drivers/net/phy/aquantia_main.c:361: phydev->interface = PHY_INTERFACE_MODE_10GKR; > drivers/net/phy/aquantia_main.c:499: phydev->interface != PHY_INTERFACE_MODE_10GKR) > drivers/net/phy/sfp-bus.c:340: return PHY_INTERFACE_MODE_10GKR; > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:1117: return interface == PHY_INTERFACE_MODE_10GKR || > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:1203: case PHY_INTERFACE_MODE_10GKR: > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:1652: case PHY_INTERFACE_MODE_10GKR: > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:4761: case PHY_INTERFACE_MODE_10GKR: > drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:4783: case PHY_INTERFACE_MODE_10GKR: > > We should fix this, if it's incorrect. > > > If we add something else, then the problem becomes what to do about > > that lot - one of the problems is, it seems we're going to be breaking > > DT compatibility by redefining 10gbase-kr to be correct. > > We need the committer/maintainer to update that to a correct value. The general principle is, we don't break existing DT - in that, we expect DT files from current kernels to work with future kernels. So, we're kind of stuck with "10gbase-kr" being used for this at least in the medium term. By all means introduce "xfi" and "sfi" if you think that there is a need to discriminate between the two, but I've seen no hardware which that treats them any differently from 10gbase-r. If we want to support real 10gbase-kr, then I think we need to consider how to do that without affecting compatibility with what we already have. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up