From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 39CB522ACEE; Thu, 24 Apr 2025 13:20:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745500815; cv=none; b=Mqy88c4/joM9UcuCcYPtvLhhtsRr+V3Fm0b378sk1K6ex9TwhwTvi+tz2GlJvdkYoim7wRy6IOb8yTcwKNbgJaEeTIu6AxcaZi2XuRWnBhsgnyGvt0rsRvMh+xn0EGHUJN+f1YoYRmUbeJu4apC4vD6NEeCpqQaT4/pmenYWkmo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745500815; c=relaxed/simple; bh=UDwTz3NjkSUIxb/FAonWmIRVyeFImDM2LeNU/2yGzRA=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=R8WRnS8McSIeqDMCsuA545QRBD5M1mDUuFut/Fj65bTpdbZOWp8cjzWhRJKdKEIwEH699CuDINNul6qackJQ8ltkd7EwxGFerPxO+dax6BxFNJfnQM8iDQU6c9yRbYjD6X7YsDohzZPpSeX3RE7uKS+9bH4cvpdDDGn5xPB1pMk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6DC8F1063; Thu, 24 Apr 2025 06:20:07 -0700 (PDT) Received: from donnerap.manchester.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9A2CC3F66E; Thu, 24 Apr 2025 06:20:09 -0700 (PDT) Date: Thu, 24 Apr 2025 14:20:06 +0100 From: Andre Przywara To: Andrew Lunn Cc: Yixun Lan , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , Maxime Ripard , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH 4/5] arm64: dts: allwinner: a527: add EMAC0 to Radxa A5E board Message-ID: <20250424142006.021d6ab4@donnerap.manchester.arm.com> In-Reply-To: <6e9c003e-2a38-43a7-8474-286bdb6306a0@lunn.ch> References: <20250423-01-sun55i-emac0-v1-0-46ee4c855e0a@gentoo.org> <20250423-01-sun55i-emac0-v1-4-46ee4c855e0a@gentoo.org> <20250424014120.0d66bd85@minigeek.lan> <20250424100514-GYA48784@gentoo> <6e9c003e-2a38-43a7-8474-286bdb6306a0@lunn.ch> Organization: ARM X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.32; aarch64-unknown-linux-gnu) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 24 Apr 2025 14:19:59 +0200 Andrew Lunn wrote: Hi Andrew, > > I'd not bother to try other combinations, and just stick to vendor's > > settings > > Vendors get stuff wrong all the time. Just because it works does not > mean it is correct. And RGMII delays are very frequently wrong because > there are multiple ways to get a link which works, but don't follow > the DT binding. Speaking of which: do you know of a good method to verify the delay timing? Is there *something* which is sensitive to those timings and which can be easily checked and qualified? I just tried iperf3 yesterday, but didn't spot any real change in the numbers when toying with those delay values. As mentioned in the other email, we can easily hack the values at runtime, so if there is a way to get some "quality" value, this could even be automated. Thanks, Andre