From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.tipi-net.de (mail.tipi-net.de [194.13.80.246]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0426846D2DA; Mon, 12 Oct 2026 13:18:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.13.80.246 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791811113; cv=none; b=CeCwTagLhJFSZi1P1S66Ss/B2YgYoW4+PeG8mGuNJo7wnMXXjICra8vfoJ8qwIGK9erYHS8EupBsFlfQ4eKVtcJrNT2/mzZQt978VHVphLtDrYYB+CUHjpcnYLaWrDQl3bopI3gnI6k+z1a3aSIMFf0rcSaswV989KbXDYKMEE0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791811113; c=relaxed/simple; bh=Bq/Kjg6CoCViVVMbPOG+5JtQptYfGBlE43kVe6rqTgU=; h=MIME-Version:Date:From:To:Cc:Subject:In-Reply-To:References: Message-ID:Content-Type; b=AC4Vw06o79pbPlhWWDwJSTwvvQ+4E7MUIjjPLIdBRqfoElIRq2sIOAqCXpaNKRh0m88jd+T97eJ9ytZp7yuDWhy5ML3AqnP1MPt7o6G1Z+Ky7xiUncxyuROtxae2H9afbXQNeGsgvrhnNWVXz/0jxv1ohgN28Ezkd9tezaC6IAQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de; spf=pass smtp.mailfrom=tipi-net.de; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b=HwqI2EOv; arc=none smtp.client-ip=194.13.80.246 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b="HwqI2EOv" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 07A3EA012B; Mon, 12 Oct 2026 15:18:21 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tipi-net.de; s=dkim; t=1791811104; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=Bq/Kjg6CoCViVVMbPOG+5JtQptYfGBlE43kVe6rqTgU=; b=HwqI2EOvmzNJQCcgUVfX+jdD29+XEkBwuw99rgT21hWqWS8SfMH04iWELdUW7sU87gWxDx SXwFVowM1FdnPmuT6J88AXonOFyMv1efY8AfB5J8lvL7TG+JcwZkUaY13W09zUJwZpZ6Ob 152r3huJ8Ehi5OJNjMAf0Jbj01i9rwzCYyBNYbs1wOZbXVDOUfnf9ApwefUaVVGDJsr2IL 7jEIDbVjh6b+YQvMDWyg4tYSuUJf34OCoa0PLdMgdmpDB+pvfbXVmT9mPhMFZtsGU+0GBX CXiclk4ppm4HitJwogpbAZqy03Tzh6hJa0KBwoau5lUABrwlLP5JM2fS113vmg== Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Mon, 12 Oct 2026 15:18:21 +0200 From: Nicolai Buchwitz To: James Clark Cc: Florian Fainelli , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Andrew Lunn , Heiner Kallweit , Richard Cochran , Doug Berger , =?UTF-8?Q?Th=C3=A9o_Lebrun?= , Russell King , Conor Dooley , Broadcom internal kernel review list , Thomas Gleixner , Miroslav Lichvar , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next 5/5] net: mdio: bcm-unimac: implement timestamped MDIO writes In-Reply-To: References: <20261009143506.2507607-1-jjc@jclark.com> <20261009143506.2507607-6-jjc@jclark.com> <3b1a2994-5251-4800-8c61-b63d7a435b21@broadcom.com> <60accbd89cfaf0d4be1da5ec2fafd975@tipi-net.de> <41c32f5a6f38ec9df8a79ce896912fb9@tipi-net.de> Message-ID: <365bd3473c9375d467663738f217ac51@tipi-net.de> X-Sender: nb@tipi-net.de Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 Hi James On 12.10.2026 02:54, James Clark wrote: > [...] > Sashiko wanted write_sts limited to BCM2711 because the 63.5 to 64.5 > window has only been measured on BCM2711 and we don't have evidence > that it applies elsewhere. If it doesn't, then we could potentially > violate what PTP_SYS_OFFSET_EXTENDED promises. I think one could argue > that this is too conservative: clause 22 specifies 64 bits and the > 63.5 to 64.5 range falls out of that given a free-running MDC and some > other reasonable assumptions. Andrew made a similar point on 4/5 > (https://lore.kernel.org/netdev/c136b0ad-6d7e-4695-b988-55eb37550d01@lunn.ch/). > Florian said he wanted a compatible string but I am not sure whether > because of this or because of the clock. In any case, I am happy to do > it whichever way you and Florian decide. I'd drop the compatible. Gating on a clock on the mdio node is BCM2711 only in-tree anyway, and as Andrew said on 4/5, 64 bits is clause 22. Florian can still shout when he confirms the clock name :) > In the probe, I believe I still need to add a call to > devm_clk_get_optional() in the pdata branch, which is used when GENET > creates the UniMAC device. At the moment this branch does priv->clk = > pdata->clk, so it would not pick up the new GISB clock from the mdio > node. I think this new clock would live alongside the existing > pdata->clk: the write_sts rate would come from the mdio node clock, > but pdata->clk would be used for gating. I was not planning for this > series to make clk_set use the new GISB clock. Fine, I can do that as a follow-up together with Andrew's 2.5 MHz default once the clock is in. > [...] Thanks, Nicolai