From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f44.google.com (mail-wm1-f44.google.com [209.85.128.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 217B22C3757 for ; Wed, 17 Dec 2025 12:21:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765974085; cv=none; b=CWJHKhe43YyZjLgtsfXjOnnFuj3ZaukPS2wMUcaatQxIy2OCb32+VFMhsameREtNKQL6rrZvv7u6RGZr+PEhEDMF7cjMVEFzfcFv461cXnuPdN1tHJ4Mvg/C151iRqRCSQOCIpEKvwBK2R9bwe6k5CmRm2tSjkH+AA1veIrjj3c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765974085; c=relaxed/simple; bh=fny9SFTxturF7015JakyAPXxKQIp2Ma/cwO/hVKlOlQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=iLbt7PSZM3D+R+VbU/H6J/cQPmb7uHt+OADNuzVL7rCLWCwdbItiB4sp+4NyRlwjYvx93FCcl13JfFU42Zd0Q8tIhEsTENELEh3HeM7Sl2y606i2mMmNHUo76uPq/JMAK/VMzS1PY78KjX6poY6aYbrCY694g39xgra7leaX6rU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=SNMV+RRd; arc=none smtp.client-ip=209.85.128.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SNMV+RRd" Received: by mail-wm1-f44.google.com with SMTP id 5b1f17b1804b1-47a8195e515so46660995e9.0 for ; Wed, 17 Dec 2025 04:21:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1765974082; x=1766578882; darn=vger.kernel.org; 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=DYXq2m6KIBeaHm0Y860B+iQgDTaW343HwilrkCCxiCU=; b=SNMV+RRd6noDNpXs2aKVhos/B28mz0h992v9tw4Rb2eWuEIE8FaQlpeELC4w85+Xgx 3Syxrufaeu+7L2zMEvd0V4ByRSFlmltdrPjyM4UUQKKbyuFXiYvYP6egaqyLaNDaCjYN 3vt0ZX4VECLqxLzgC95/J8cea2rj9JC/RolhB7sqpY/DSwSm8nvAWtnIGZK1a9i6uMGX wZqVwbsmAtEVaGDEr5hdm8ee1cEpi1UXEtJ9TZvF+QveAHcuZziMzxFN0dRb1iwssIlf WzUAPnXxbpn1ff7JO+xrDmukXlsfYjjGv2GwQAeDyPEEZ9brEWzmIitMaxTa7BXkdKeS NfLQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1765974082; x=1766578882; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=DYXq2m6KIBeaHm0Y860B+iQgDTaW343HwilrkCCxiCU=; b=Wl+934xvLD3KaS+m7upbjRGzl2B6MeHs8jknuQMKVulCSjE+cLTGQZsjYMLBEDd2/6 7vDNCXBDNi4KycUvI0VkLkN/fBFtL0q/PQgsCZoUiouputH/frJ0jV2q3Cq83HttBTfu 76om/WEfCEtKMQ54pjPYwm63nEtMjsR1sL/gO9iiLuEkWvMQ5BL0r4XqQHl4VxEmCdt9 dwjXFgrZcUFqoL9OLNad1zdfmcmhEJWWorb2iUvkIhprJQrQxLwaiInoznt12ZgCRek+ VFrbSogBk27rbyWi3l3zwutHnSzJmq2m5LtZG/eX9zL0bKXDFE2zM61WEYd99d1kFVSd XOGg== X-Forwarded-Encrypted: i=1; AJvYcCWnNJHyyEMBmbvv1lAifdJIRQiRDXm4vHiFn3tDoobNlvvlJuUxdju082WJK32J6Uu+YtbuUhP8SxOJlDI=@vger.kernel.org X-Gm-Message-State: AOJu0YzoZl1wuv0NG9R26xjJ0oSl9BxPUjlIRl3EOlrM4HB5E2fuwyXT Y6pQxmMVRS5gfZAa4QZHR67kDDXkaaqSZGzDE2p3gE84a4tYnE3/VuYn X-Gm-Gg: AY/fxX5a5LxKdAw/hF4M/DB/GyekfVoL4ieiwbZxWWPIvk49VYcFH2PysBy+0ogxLoP 35KD6jTYXudD4AT+kX+oEReK+xBKe6e9FSSdhIwSSGUwUEzO4Ze+usIKKgKAZegGhQUNb/aVolC 3hiYyB5Bfo/9A1FjLAAd/j5P/FuXe54Xlot7Sw2ZbS/TLfAqaJ2/8hsi0zaDi7CsupH0cukrFxn ILB4HLXSv/u3LfzkOcMsgXBwPfpWe+K6wgWZ7mr540C1mk6nc2wsc8E0OmkOWGWr5Lt+cFHF9Ak 9qsk/m6k6GjA3+ZreJBYzlaBjDX8DepMA+/WrB49njRP9LQoPOaVQeDVr5s7AJl8Rl+qJoR8DFv Px0WfuLm5CkCsa4KJDO2aSPC/fbABK18Z1j/jRoHZHzcJFqkN36vTksBnHOYPNtdy0SeLPNbBwP phtrMUB3n6I+Q= X-Google-Smtp-Source: AGHT+IEHnifimtj7VdGfz6MjbhY2lEOpq0xdu6/7cpFkjgiXCk7n3y9Quh4Rc68+jvf5AZydr2IWWA== X-Received: by 2002:a05:600c:3486:b0:477:561f:6fc8 with SMTP id 5b1f17b1804b1-47a8f8a79e4mr188945585e9.5.1765974082138; Wed, 17 Dec 2025 04:21:22 -0800 (PST) Received: from eichest-laptop ([2a02:168:af72:0:b288:1a0e:e6f7:d63a]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-47bdc1d991fsm37975775e9.5.2025.12.17.04.21.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Dec 2025 04:21:21 -0800 (PST) Date: Wed, 17 Dec 2025 13:21:19 +0100 From: Stefan Eichenberger To: Rob Herring Cc: andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, krzk+dt@kernel.org, conor+dt@kernel.org, hkallweit1@gmail.com, linux@armlinux.org.uk, geert+renesas@glider.be, ben.dooks@codethink.co.uk, netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, francesco.dolcini@toradex.com, rafael.beims@toradex.com, Stefan Eichenberger Subject: Re: [PATCH net-next v1 2/3] dt-bindings: net: micrel: Add keep-preamble-before-sfd Message-ID: References: <20251212084657.29239-1-eichest@gmail.com> <20251212084657.29239-3-eichest@gmail.com> <20251215140330.GA2360845-robh@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@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: On Wed, Dec 17, 2025 at 10:58:54AM +0100, Stefan Eichenberger wrote: > On Mon, Dec 15, 2025 at 08:03:30AM -0600, Rob Herring wrote: > > On Fri, Dec 12, 2025 at 09:46:17AM +0100, Stefan Eichenberger wrote: > > > From: Stefan Eichenberger > > > > > > Add a property to activate a Micrel PHY feature that keeps the preamble > > > enabled before the SFD (Start Frame Delimiter) is transmitted. > > > > > > This allows to workaround broken Ethernet controllers as found on the > > > NXP i.MX8MP. Specifically, errata ERR050694 that states: > > > ENET_QOS: MAC incorrectly discards the received packets when Preamble > > > Byte does not precede SFD or SMD. > > > > It doesn't really work right if you have to change the DT to work-around > > a quirk in the kernel. You should have all the information needed > > already in the DT. The compatible string for the i.MX8MP ethernet > > controller is not sufficient? > > Is doing something like this acceptable in a phy driver? > if (of_machine_is_compatible("fsl,imx8mp")) { > ... > } > > That would be a different option, rather than having to add a new DT > property. Unfortunately, the workaround affects the PHY rather than the > MAC driver. This is why we considered adding a DT property. Francesco made a good point about this. The i.MX8MP has two MACs, but only one of them is affected. Therefore, checking the machine's compatible string would not be correct. As far as I know, checking the MAC's compatible string from within the PHY driver is also not good practice, is it?