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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 134B5C54EBC for ; Tue, 3 Jan 2023 15:57:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231292AbjACP4o (ORCPT ); Tue, 3 Jan 2023 10:56:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233454AbjACP4j (ORCPT ); Tue, 3 Jan 2023 10:56:39 -0500 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A233DA1AD; Tue, 3 Jan 2023 07:56:38 -0800 (PST) Received: by mail-ed1-x529.google.com with SMTP id b88so37104941edf.6; Tue, 03 Jan 2023 07:56:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=cUgk7t5CLogpADp6v+03F2a0C4ndvH9yI7BzPUoVTz8=; b=Nlop0vV2rhk/Y14mg/LYKMI/LgbnDu0LklT8ZlGkVGT6ndSrTIzsmfL+UKV+rctl7C LTgsO6ABsOsdupP0jMFKDPkeJOR/AjFdfRo1Kg92jTO3bYdUXQy0W2AOAvF67poVg1Ax M1E36j+goZnA9IKiW00QGwlwffPb/29IZCIUJRj5YM3kGL/tOGPHmNWLJ32If2ZsqA6V P1G2DWN8BnASIEwuGtlrA933d7Yn9FSU/Z3x+ITFmaWt+G4dhW7kYHic9RylMsTtx5f2 h0dZVKaxxZc4PhVmuSZ6Qtq4+903piGIKgA58TaiWTJ4GgrOy0O/gWNWrVTaOitxuPgL bavA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=cUgk7t5CLogpADp6v+03F2a0C4ndvH9yI7BzPUoVTz8=; b=7qF6lGZgptzaH3MVXs0Ccj3PeoiAZt3SQiSb1CnRmL2AJg8x3gw2vJ38HWJntW4Lb0 WwPEaiyQnpUkYJ2HQMaIQNSNOwhSaVhL9v57eIjpPrKxwe3a/en0oI1qGcQdkHfh9jr1 /Mdz/JvCPeeJZIUjbvMRtR76UxFT9O0B3FY7FcZuDpGBVfSUnu7iAATmE23UcLRqfDwf s8cPnJq0pLFZYxJJCZg4G1myhlSk5cQBPq1Yy00RMkLPlVPDgwagalgJV+Ia6B02UyhB O2W0YBEDnuGEwxHu5tRa2/1aO+7FPIaOnrlufOTb/ulroh6dnO6m69AuooEdQx0sI39N RGzw== X-Gm-Message-State: AFqh2ko2hUbURT1JZqAoLc1ylPp5cKaF3dCF9PVZkfNb0vKLOAlmfRZl MLcFlsEPv28/BMY/7QxlRD0= X-Google-Smtp-Source: AMrXdXtoAYN/JnDVDN1YkdRe3Sjl9+sUDPRbeIocCAM+QeCzmE90ykdzaDAgpT+gUrrkq+LbtncKDA== X-Received: by 2002:aa7:d04d:0:b0:46c:d905:b9e8 with SMTP id n13-20020aa7d04d000000b0046cd905b9e8mr37622928edo.23.1672761396798; Tue, 03 Jan 2023 07:56:36 -0800 (PST) Received: from skbuf ([188.26.185.118]) by smtp.gmail.com with ESMTPSA id g3-20020a170906538300b0082535e2da13sm14252877ejo.6.2023.01.03.07.56.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Jan 2023 07:56:36 -0800 (PST) Date: Tue, 3 Jan 2023 17:56:33 +0200 From: Vladimir Oltean To: Andrew Lunn Cc: Michael Walle , Heiner Kallweit , Russell King , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jose Abreu , Sergey Shtylyov , Wei Fang , Shenwei Wang , Clark Wang , NXP Linux Team , Sean Wang , Landen Chao , DENG Qingfang , Florian Fainelli , Matthias Brugger , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Geert Uytterhoeven , Luiz Angelo Daros de Luca Subject: Re: [PATCH RFC net-next v2 11/12] net: dsa: Separate C22 and C45 MDIO bus transaction methods Message-ID: <20230103155633.tfdxncl75s4tb2ln@skbuf> References: <20221227-v6-2-rc1-c45-seperation-v2-0-ddb37710e5a7@walle.cc> <20221227-v6-2-rc1-c45-seperation-v2-0-ddb37710e5a7@walle.cc> <20221227-v6-2-rc1-c45-seperation-v2-11-ddb37710e5a7@walle.cc> <20221227-v6-2-rc1-c45-seperation-v2-11-ddb37710e5a7@walle.cc> <20230103153134.utalc6kw3l34dp4s@skbuf> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Jan 03, 2023 at 04:48:59PM +0100, Andrew Lunn wrote: > > Since clause 45 PHYs are identified by the "ethernet-phy-ieee802.3-c45" > > compatible string (otherwise they are C22), then a PHY which is not > > described in the device tree can only be C22. So this is why > > ds->slave_mii_bus only deals with clause 22 methods, and the true reason > > behind the comment above. > > > > But actually this premise is no longer true since Luiz' commit > > fe7324b93222 ("net: dsa: OF-ware slave_mii_bus"), which introduced the > > strange concept of an "OF-aware helper for internal PHYs which are not > > described in the device tree". After his patch, it is possible to have > > something like this: > > > > ethernet-switch { > > ethernet-ports { > > port@1 { > > reg = <1>; > > }; > > }; > > > > mdio { > > ethernet-phy@1 { > > compatible = "ethernet-phy-ieee802.3-c45" > > reg = <1>; > > }; > > }; > > }; > > > > As you can see, this is a clause 45 internal PHY which lacks a > > phy-handle, so its bus must be put in ds->slave_mii_bus in order for > > dsa_slave_phy_connect() to see it without that phy-handle (based on the > > port number matching with the PHY number). After Luiz' patch, this kind > > of device tree is possible, and it invalidates the assumption about > > ds->slave_mii_bus only driving C22 PHYs. > > My memory is hazy, but i think at the time i wrote these patches, > there was no DSA driver which made use of ds->slave_mii_bus with > C45. So i took the short cut of only supporting C22. Actually I believe that in v1 you did extend ds->ops with C45 methods, but it's me who told you to remove them: https://patchwork.kernel.org/project/netdevbpf/patch/20220508153049.427227-10-andrew@lunn.ch/#24852813 > > Those DSA drivers which do support C45 all register their bus directly > with the MDIO core. And rightfully so. IMHO, letting DSA allocate ds->slave_mii_bus out of driver writer sheer convenience (a secondary purpose) should be deprecated, unless the reason for using ds->slave_mii_bus is the lack of a phy-handle (the primary purpose). It becomes that more confusing to have to extend dsa_switch_ops with 2 more methods which serve the secondary purpose but not the primary one. > So Luiz patches may allow a C45 bus, but are there any drivers today > actually using it? I sent a private email to Luiz a few minutes ago asking him to confirm.