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 2254EC001DF for ; Mon, 31 Jul 2023 07:01:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230331AbjGaHA7 (ORCPT ); Mon, 31 Jul 2023 03:00:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41988 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230317AbjGaHA5 (ORCPT ); Mon, 31 Jul 2023 03:00:57 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 299C2185 for ; Mon, 31 Jul 2023 00:00:56 -0700 (PDT) Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.ext.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1qQMtS-0004SZ-1N; Mon, 31 Jul 2023 09:00:38 +0200 Message-ID: Date: Mon, 31 Jul 2023 09:00:29 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.1 Subject: Re: [PATCH v2] net: stmmac: correct MAC propagation delay Content-Language: en-US, de-DE To: Richard Cochran Cc: Giuseppe Cavallaro , Alexandre Torgue , Jose Abreu , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , Russell King , patchwork-jzi@pengutronix.de, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de, kernel test robot References: <20230719-stmmac_correct_mac_delay-v2-1-3366f38ee9a6@pengutronix.de> <729dd79e-83aa-0237-1edd-1662a6ae28cd@pengutronix.de> From: Johannes Zink In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 2a0a:edc0:0:900:1d::77 X-SA-Exim-Mail-From: j.zink@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Richard, On 7/27/23 15:36, Richard Cochran wrote: > On Thu, Jul 27, 2023 at 09:20:10AM +0200, Johannes Zink wrote: >> Hi Richard, >> >> On 7/26/23 22:57, Richard Cochran wrote: >>> On Mon, Jul 24, 2023 at 12:01:31PM +0200, Johannes Zink wrote: >>> >>> Earlier versions of the IP core return zero from these... >>> >>>> +#define PTP_TS_INGR_LAT 0x68 /* MAC internal Ingress Latency */ >>>> +#define PTP_TS_EGR_LAT 0x6c /* MAC internal Egress Latency */ >>> >> >> good catch. Gonna send a v3 with a check to and set the values for dwmac v5 only. > > AFAICT there is no feature bit that indicates the presence or absence > of these two registers. > > Are you sure that *all* v5 IP cores have these? > > I am not sure. I cannot tell for sure either, since I have datasheets for the i.MX8MP only. Maybe Kurt has some insights here, as he has additional hardware available for testing? Nevertheless, I am going to add a guard to only use the correction codepath on i.MX8MP in v3 for the time being, we can add other hardware later trivially if they support doing this. Best regards Johannes > > Thanks, > Richard > > -- Pengutronix e.K. | Johannes Zink | Steuerwalder Str. 21 | https://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686| Fax: +49-5121-206917-5555 |