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 7D641C83F12 for ; Thu, 31 Aug 2023 10:37:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229882AbjHaKhk (ORCPT ); Thu, 31 Aug 2023 06:37:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229613AbjHaKhj (ORCPT ); Thu, 31 Aug 2023 06:37:39 -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 18236CF3 for ; Thu, 31 Aug 2023 03:37:36 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qbf31-0002Kq-EB; Thu, 31 Aug 2023 12:37:11 +0200 Received: from ore by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1qbf2z-00067y-Fd; Thu, 31 Aug 2023 12:37:09 +0200 Date: Thu, 31 Aug 2023 12:37:09 +0200 From: Oleksij Rempel To: "Russell King (Oracle)" Cc: Lukasz Majewski , Tristram.Ha@microchip.com, Eric Dumazet , Andrew Lunn , davem@davemloft.net, Woojung Huh , Vladimir Oltean , Florian Fainelli , Jakub Kicinski , Paolo Abeni , UNGLinuxDriver@microchip.com, Heiner Kallweit , Michael Walle , Horatiu Vultur , Arun Ramadoss , Oleksij Rempel , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] net: phy: Provide Module 4 KSZ9477 errata (DS80000754C) Message-ID: <20230831103709.GC17603@pengutronix.de> References: <20230831072527.537839-1-lukma@denx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ore@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 On Thu, Aug 31, 2023 at 11:28:00AM +0100, Russell King (Oracle) wrote: > On Thu, Aug 31, 2023 at 09:25:27AM +0200, Lukasz Majewski wrote: > > diff --git a/include/linux/micrel_phy.h b/include/linux/micrel_phy.h > > index 8bef1ab62bba..eed474fc7308 100644 > > --- a/include/linux/micrel_phy.h > > +++ b/include/linux/micrel_phy.h > > @@ -44,6 +44,7 @@ > > #define MICREL_PHY_50MHZ_CLK 0x00000001 > > #define MICREL_PHY_FXEN 0x00000002 > > #define MICREL_KSZ8_P1_ERRATA 0x00000003 > > +#define MICREL_NO_EEE 0x00000004 > > Erm... Maybe someone should clarify this... we have in the code the > following tests for these "flags": > > /* Support legacy board-file configuration */ > if (phydev->dev_flags & MICREL_PHY_50MHZ_CLK) { > priv->rmii_ref_clk_sel = true; > priv->rmii_ref_clk_sel_val = true; > } > > /* Skip auto-negotiation in fiber mode */ > if (phydev->dev_flags & MICREL_PHY_FXEN) { > phydev->speed = SPEED_100; > return 0; > } > > if (phydev->dev_flags & MICREL_KSZ8_P1_ERRATA) > return -EOPNOTSUPP; > > /* According to KSZ9477 Errata DS80000754C (Module 4) all EEE modes > * in this switch shall be regarded as broken. > */ > if (phydev->dev_flags & MICREL_NO_EEE) > phydev->eee_broken_modes = -1; > > Is it intentional that setting MICREL_PHY_50MHZ_CLK on its own also > activates the MICREL_KSZ8_P1_ERRATA and vice versa? Is it intentional > that setting MICREL_PHY_FXEN also activates MICREL_KSZ8_P1_ERRATA and > vice versa? > > To me, this looks horribly broken, and this patch just perpetuates the > brokenness (but at least 0x4 doesn't overlap with the other flags.) > > If it is intentional, then MICREL_KSZ8_P1_ERRATA should be defined to > make it explicit - in other words, as > (MICREL_PHY_FXEN|MICREL_PHY_50MHZ_CLK). If not, all these flags should > be defined using (1 << n) or BIT() to make it explicit that they're a > bit, and not just a hex number that gets incremented when the next flag > is added. Indeed, it is broken. I'll send a fix for this one. MICREL_KSZ8_P1_ERRATA should be BIT(3) and MICREL_NO_EEE BIT(4) Thx! Regards, Oleksij -- 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 |