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 BC2E3C44539 for ; Wed, 22 Jul 2026 13:40:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=wr+ewd5waDN6ADYJpilEPIvuynye3ldhe8wIwOoFlp0=; b=EeRYHPyiGbo1tdcSFX8/9Wsx5z UbOhy0uJ3b9/ydagWm4XF1njWy646TMrSBWz/CWphbCS+5MSp9P44fIe1fP6JJDx/UWwvuqaNfGW/ e92RicZrWJgmkRGy4/G8Gvj0yIVXun3NSG+FTpf2WsjBv97tpf6f+dZ8VicwPWl6f3oxhpQlbfvkL AFTo4lQJRyyrbtloOQKTS1ftJ4NYy90t5occGOvQWrTK4gctMPWiLKkeLNb2BscRiPDWtdWz1X0Wo IBq9lKiGDGBlGy8AalmZHeOTXOo7r8qDvRSnqxYrE3UvESZZC1sxyeM/dM5opAqW5Z8MydvNKqcbw QtSus1uA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmXBT-0000000BvXj-2xKo; Wed, 22 Jul 2026 13:40:27 +0000 Received: from smtpout-03.galae.net ([185.246.85.4]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmXBP-0000000BvWW-2VWa for linux-arm-kernel@lists.infradead.org; Wed, 22 Jul 2026 13:40:25 +0000 Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-03.galae.net (Postfix) with ESMTPS id E38F54E40ECF; Wed, 22 Jul 2026 13:40:18 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id AF3F360388; Wed, 22 Jul 2026 13:40:18 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 6A6DF11BD03C7; Wed, 22 Jul 2026 15:40:09 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1784727617; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=wr+ewd5waDN6ADYJpilEPIvuynye3ldhe8wIwOoFlp0=; b=OOO99RNAiChT0FMMosou7lSmLXLDP2UqgctMVht4RjYFcfQT7iyB40FxEX3mU5geMkypIb DfHxt/nFmORYZW78euYSK+LtlO7jR+8+WCMRCIQScXtCGzq8cCer3VmZlefHDrPVq2lWv3 HbHK14gYV7Ep0bfNoyAuhcS/h5J7hkLpoWXrO7sUh+PeomdeGuVibTTtxdF2MuHWDfEsBW O/dxLhbSoT518ME6bO3dNotb5WdC8As/hP8tF9qL8zxysD7/ly/B2Xww4nwVrZto7Yr2bA xm+rp+LruZ5H1Bo65teOA3GqnS/hNg+6E4MvNDvreYCI1cLHfmH7OXuKXMDiBQ== Message-ID: Date: Wed, 22 Jul 2026 15:40:08 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net] net: stmmac: Skip PHY attach if custom PCS is in use To: Zxyan Zhu , netdev@vger.kernel.org Cc: Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , Alexandre Torgue , Russell King , Russell King , Serge Semin , Romain Gantois , Hariprasad Kelam , linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mohd Ayaan Anwar References: <20260722131918.685761-1-zxyan0222@gmail.com> From: Maxime Chevallier Content-Language: en-US In-Reply-To: <20260722131918.685761-1-zxyan0222@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260722_064023_810266_D574F80A X-CRM114-Status: UNSURE ( 9.59 ) X-CRM114-Notice: Please train this message. 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, +Mohd On 7/22/26 15:19, Zxyan Zhu wrote: > When a platform provides a custom PCS via the pcs_init callback > (e.g., for USXGMII with in-band autoneg), the MAC's phylink_pcs > is already configured. In this case, phylink validates against > the PCS's supported interfaces and manages link state through > the PCS, so no traditional PHY device is needed. > > Without this, stmmac_init_phy() falls through to the > no-phy-node path and errors out with "no phy found" when > the DT has no phy-handle for such interfaces. > > Skip the PHY attach when priv->hw->phylink_pcs is already set > and no phy-handle is specified in the device tree, allowing > platform PCS implementations to handle the link autonomously. Hmpf this bug again... There have been multiple attempts at solving this, cf this thread : https://lore.kernel.org/netdev/E1w66jW-0000000E3qS-23fW@rmk-PC.armlinux.org.uk/ Now, there wasn't any conclusion on that, but I _think_ the proper solution is to re-apply Russell's original patch (the one in the link above) and to add this current patch on top of it. Russell states that this may (will ?) break qcom-ethqos, but OTOH we're in need for a solution here, and with the pace of PCS-related work that impacts stmmac, there's going to be a point where we may need to think about compatibility. TBF I don't understand the qcom-ethqos issue, maybe Mohd can help with testing here ? Maxime