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 X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6CFEC10F00 for ; Fri, 6 Mar 2020 07:43:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 92D64217F4 for ; Fri, 6 Mar 2020 07:43:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726026AbgCFHnB (ORCPT ); Fri, 6 Mar 2020 02:43:01 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:55591 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725853AbgCFHnB (ORCPT ); Fri, 6 Mar 2020 02:43:01 -0500 Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=[IPv6:::1]) by metis.ext.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1jA7dC-0000a2-UJ; Fri, 06 Mar 2020 08:42:50 +0100 Subject: Re: [PATCH] ARM: mach-imx6q: add ksz9131rn_phy_fixup To: Andrew Lunn , Oleksij Rempel Cc: Kate Stewart , Fabio Estevam , Greg Kroah-Hartman , Sascha Hauer , Russell King , linux-kernel@vger.kernel.org, Philippe Schenker , NXP Linux Team , Pengutronix Kernel Team , Thomas Gleixner , Shawn Guo , Allison Randal , linux-arm-kernel@lists.infradead.org References: <20200305134928.19775-1-philippe.schenker@toradex.com> <20200305143805.dk7fndblnqjnwxu6@pengutronix.de> <20200305165145.GA25183@lunn.ch> From: Ahmad Fatoum Message-ID: <7191ffe6-642a-477c-ec37-e37dc9be4bf8@pengutronix.de> Date: Fri, 6 Mar 2020 08:42:47 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200305165145.GA25183@lunn.ch> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: a.fatoum@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 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Andrew, On 3/5/20 5:51 PM, Andrew Lunn wrote: > On Thu, Mar 05, 2020 at 03:38:05PM +0100, Oleksij Rempel wrote: >> Hi Philippe, >> >> On Thu, Mar 05, 2020 at 02:49:28PM +0100, Philippe Schenker wrote: >>> The MAC of the i.MX6 SoC is compliant with RGMII v1.3. The KSZ9131 PHY >>> is like KSZ9031 adhering to RGMII v2.0 specification. This means the >>> MAC should provide a delay to the TXC line. Because the i.MX6 MAC does >>> not provide this delay this has to be done in the PHY. >>> >>> This patch adds by default ~1.6ns delay to the TXC line. This should >>> be good for all boards that have the RGMII signals routed with the >>> same length. >>> >>> The KSZ9131 has relatively high tolerances on skew registers from >>> MMD 2.4 to MMD 2.8. Therefore the new DLL-based delay of 2ns is used >>> and then as little as possibly subtracted from that so we get more >>> accurate delay. This is actually needed because the i.MX6 SoC has >>> an asynchron skew on TXC from -100ps to 900ps, to get all RGMII >>> values within spec. >> >> This configuration has nothing to do in mach-imx/* It belongs to the >> board devicetree. Please see DT binding documentation for needed >> properties: >> Documentation/devicetree/bindings/net/micrel-ksz90x1.txt > > It probably does not even need that. Just > > phy-mode = Looks to me like this isn't supported by the Micrel PHY driver or am I missing something? Cheers Ahmad -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |