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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CB99C678D4 for ; Thu, 2 Mar 2023 10:38:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229872AbjCBKiB (ORCPT ); Thu, 2 Mar 2023 05:38:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229504AbjCBKiA (ORCPT ); Thu, 2 Mar 2023 05:38:00 -0500 Received: from relay10.mail.gandi.net (relay10.mail.gandi.net [217.70.178.230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2008065AF for ; Thu, 2 Mar 2023 02:37:56 -0800 (PST) Received: (Authenticated sender: kory.maincent@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id BE248240003; Thu, 2 Mar 2023 10:37:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1677753475; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to; bh=RT8w/1WpUo5/rnQglCQFdyLexLq+tUoVxw4JfOD9Pqg=; b=WU37j1YIfWFxJSjjTe2axRHbmuCEPQow0Uj4sqkAyUnZAPsGtjkOqjHv72XBO8KCujOFu/ 8flcewz3PtgSkPNQA3rF6EckQYJchY9HxGuK+8+ZH2okY5X+alSNj4PkplNJ20pkXbMj6j aJtAOnOO+o+X3+h2mx/5r4Re5KcNaUVuVGzf8fftVJ0W5HTndRDAuGchvWnpGgsO/p/COA j076dJz9WZ1eql1cd+946ge3/RjbBysVR+Us/1hcOz/pHK4G7Jy637bWY7EVCk0qtCCtsp q6ymnTsdRMahAzOwGJNhEb2PI4szMiHQRc6HrRrwGSiaDNfOH2bvZHJZWR50MA== Date: Thu, 2 Mar 2023 11:37:52 +0100 From: =?UTF-8?B?S8O2cnk=?= Maincent To: linux@armlinux.org.uk Cc: andrew@lunn.ch, davem@davemloft.net, f.fainelli@gmail.com, hkallweit1@gmail.com, kuba@kernel.org, netdev@vger.kernel.org, richardcochran@gmail.com, Maxime Chevallier , Thomas Petazzoni Subject: Re: [PATCH RFC net-next] net: phy: add Marvell PHY PTP support Message-ID: <20230302113752.057a3213@kmaincent-XPS-13-7390> Organization: bootlin X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) In-Reply-To: <20200729105807.GZ1551@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hello Russell, > I have the situation on a couple of devices where there are multiple > places that can do PTP timestamping: >=20 > - the PHY (slow to access, only event capture which may not be wired, > doesn't seem to synchronise well - delay of 58000, frequency changes > every second between +/-1500ppb.) > - the Ethernet MAC (fast to access, supports event capture and trigger > generation which also may not be wired, synchronises well, delay of > 700, frequency changes every second +/- 40ppb.) Does this test have been made with the marvell 88E151x PHY? On my side with a zynqMP SOM (cadence MACB MAC) the synchronization of the = PHY PTP clock is way better: +/-50ppb. Do you have an idea about the difference= ?=20 Which link partner were you using? stm32mp157 hardware PTP on my side. On the thread mail we are talking about PTP rate scale but as we can see you and I have really not the same synchronisation on this PHY PTP. How could we set a PTP rate scale in the driver if on two different board the result vary a lot? Although I don't understand why. I have also differences with the PTP MAC but it is expected as it is not the same MAC. Regards, K=C3=B6ry