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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8D71EC3DA7D for ; Tue, 3 Jan 2023 17:41:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=c6pN4hXiZ4JsemB46vxj8MnQAtiMQPDunhUgIRvyFJ4=; b=DOLlua1X5+tw9z p6wwcRMpxNJQwFqcZ9YhQNrhVk0Jc1+IoRU4mEDiHmk/myWNm0FHUZy1XFJN2YzQTdEc6aQYWijqQ pmVr7F4f3w2Le3BiR82xoSe8elZuu70ygqwjOe6a7a5rNLGezhUHEt70pEs9ye7YPbNQb5GDdU6/0 Oi/ecNEJHnpwesWrVLbVtuh8FimwIhbX0c/RsHJZvvn8yo11z7AkmDBFcHr45jFKlsp0Jz3iqCZXi O1AHe7wdSfOkhRxQIDKXT/QTZbFg7bnb44yIPyrxipkitMShnUtlrnrGmOvNzfDp+kxCmmrWkyI6Q lReZw+355gPCTMZe2p+A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pClGZ-003V85-N6; Tue, 03 Jan 2023 17:40:00 +0000 Received: from vps0.lunn.ch ([156.67.10.101]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pCjXd-002cHU-TJ; Tue, 03 Jan 2023 15:49:31 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=Bl7zNPyg/17oKHhmiSL8xm9swJqehU6paU/Oyhzf6vI=; b=tugNUhosNDBEkmAtZH7CviKjAx EVZIPwfPfDBEo1tIq1mPP6dzRFul1Q9rpGo8qGLcg7AKlvemJkbedaPzVt9d2EhIBw5NcFaPsFF/D VOA707yX2El8ta6EhLXJyvw39L5fWM5yoJ+eG00iuvg/bYzUqbwgxGdCyQ1qqpn/NTIg=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1pCjX9-0013iX-VA; Tue, 03 Jan 2023 16:48:59 +0100 Date: Tue, 3 Jan 2023 16:48:59 +0100 From: Andrew Lunn To: Vladimir Oltean 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 Subject: Re: [PATCH RFC net-next v2 11/12] net: dsa: Separate C22 and C45 MDIO bus transaction methods Message-ID: 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-Disposition: inline In-Reply-To: <20230103153134.utalc6kw3l34dp4s@skbuf> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230103_074930_042138_C248F023 X-CRM114-Status: GOOD ( 17.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org > 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. Those DSA drivers which do support C45 all register their bus directly with the MDIO core. So Luiz patches may allow a C45 bus, but are there any drivers today actually using it? Andrew _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel