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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1603FC388F7 for ; Sun, 25 Oct 2020 14:29:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BBD062085B for ; Sun, 25 Oct 2020 14:29:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1416638AbgJYO3A (ORCPT ); Sun, 25 Oct 2020 10:29:00 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:43438 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2407977AbgJYO27 (ORCPT ); Sun, 25 Oct 2020 10:28:59 -0400 Received: from andrew by vps0.lunn.ch with local (Exim 4.94) (envelope-from ) id 1kWh0y-003RBd-1u; Sun, 25 Oct 2020 15:28:56 +0100 Date: Sun, 25 Oct 2020 15:28:56 +0100 From: Andrew Lunn To: Ard Biesheuvel Cc: Daniel Thompson , Sumit Garg , Alex =?iso-8859-1?Q?Benn=E9e?= , Masami Hiramatsu , Steve McIntyre , Ilias Apalodimas , "open list:BPF JIT for MIPS (32-BIT AND 64-BIT)" , Willy Liu , "David S. Miller" , Jakub Kicinski , Sasha Levin , Florian Fainelli , Heiner Kallweit , Masahisa Kojima Subject: Re: realtek PHY commit bbc4d71d63549 causes regression Message-ID: <20201025142856.GC792004@lunn.ch> References: <20201017182738.GN456889@lunn.ch> <20201017194904.GP456889@lunn.ch> <20201017230226.GV456889@lunn.ch> <20201018154502.GZ456889@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Oct 25, 2020 at 03:16:36PM +0100, Ard Biesheuvel wrote: > On Sun, 18 Oct 2020 at 17:45, Andrew Lunn wrote: > > > > > However, that leaves the question why bbc4d71d63549bcd was backported, > > > although I understand why the discussion is a bit trickier there. But > > > if it did not fix a regression, only broken code that never worked in > > > the first place, I am not convinced it belongs in -stable. > > > > Please ask Serge Semin what platform he tested on. I kind of expect it > > worked for him, in some limited way, enough that it passed his > > testing. > > > > I'll make a note here that a rather large number of platforms got > broken by the same fix for the Realtek PHY driver: > > https://lore.kernel.org/lkml/?q=bbc4d71d6354 > > I seriously doubt whether disabling TX/RX delay when it is enabled by > h/w straps is the right thing to do here. The device tree is explicitly asking for rgmii. If it wanted the hardware left alone, it should of used PHY_INTERFACE_MODE_NA. But we might be able to compromise for a cycle or two. As far as i understand the hardware, we can read the strapping. If we find the strapping resisters are present, but rgmii is in DT, print a warning that the device tree needs upgrading, and ignore the DT mode. We can add this to stable, but not net-next. Andrew