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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 CC811C43381 for ; Fri, 22 Mar 2019 12:42:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A50072070D for ; Fri, 22 Mar 2019 12:42:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388424AbfCVMmq (ORCPT ); Fri, 22 Mar 2019 08:42:46 -0400 Received: from mail-vs1-f66.google.com ([209.85.217.66]:41627 "EHLO mail-vs1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388423AbfCVMmp (ORCPT ); Fri, 22 Mar 2019 08:42:45 -0400 Received: by mail-vs1-f66.google.com with SMTP id g187so1259161vsc.8; Fri, 22 Mar 2019 05:42:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=AD/qbVxlwTE/PSkGXP1/b52LU3GyLZtqHtnftZ3fDe8=; b=QkZEZH83LbkU36QUvoDAWFb2yFhxh+ziR/RUOd5cXpKi7B0HBlrDfEW7+NlHsuLT0J 9vPnlB3n+kbb0NpD8VKm+6k1pjhmrUtje8YK7y2Z0zpaFGtqQLxgFz4mZH8ezjHlF/L6 5pdv7/Rb/LgFJo1OuI3Xh7laPkrb0o7gG5HJLulgSyKOuKG0mcBQLZtwMQEUSugnumF7 Ruu6jyYWfKVLJDfXBOhJsdJTQt3zymA7nawy0mD2bbwxCEJoVp7JmyaVMAwzxQm8VIlu sTA6S+pU/u42FPLOtJjmoFQFJf55h/r/7EEBB7uZzFnZYJWKH0N2/Rc4Cbx7xxligWIk BRsA== X-Gm-Message-State: APjAAAXq4DpHPErbcGdNY6JBAX1dlfZYpUV0AhUXh8S8Bx9M6v6q4PFl K46Rj5QbX79yw+psZu3v4RSfkhLHq6f0D+FgNJU= X-Google-Smtp-Source: APXvYqwinuQAMDKMiY7riODh/dhtGJ0BuhBJaVcAlvDyME/uMV+lDo60nFdaGKjW2VvC3IA1l7wYpJjPOeHPyMgu+rg= X-Received: by 2002:a67:d011:: with SMTP id r17mr5214599vsi.96.1553258564145; Fri, 22 Mar 2019 05:42:44 -0700 (PDT) MIME-Version: 1.0 References: <20190217132441.15139-1-marek.vasut@gmail.com> <20190322113133.GB24257@e107981-ln.cambridge.arm.com> <95d1076c-5490-3803-f394-9a0928c2cccb@gmail.com> <20190322121822.GA26257@e107981-ln.cambridge.arm.com> <9b432b16-35a1-c4ec-df97-8f6f854ab8b4@gmail.com> In-Reply-To: <9b432b16-35a1-c4ec-df97-8f6f854ab8b4@gmail.com> From: Geert Uytterhoeven Date: Fri, 22 Mar 2019 13:42:32 +0100 Message-ID: Subject: Re: [PATCH V2] PCI: rcar: Add the initialization of PCIe link in resume_noirq To: Marek Vasut Cc: Lorenzo Pieralisi , linux-pci , Kazufumi Ikeda , Gaku Inami , Marek Vasut , Geert Uytterhoeven , Phil Edworthy , Simon Horman , Wolfram Sang , Linux-Renesas Content-Type: text/plain; charset="UTF-8" Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Marek, On Fri, Mar 22, 2019 at 1:33 PM Marek Vasut wrote: > On 3/22/19 1:29 PM, Geert Uytterhoeven wrote: > > On Fri, Mar 22, 2019 at 1:18 PM Lorenzo Pieralisi > > wrote: > >> On Fri, Mar 22, 2019 at 01:09:13PM +0100, Marek Vasut wrote: > >>> On 3/22/19 12:31 PM, Lorenzo Pieralisi wrote: > >>>> On Sun, Feb 17, 2019 at 02:24:41PM +0100, marek.vasut@gmail.com wrote: > >>>>> From: Kazufumi Ikeda > >>>>> > >>>>> Reestablish the PCIe link very early in the resume process in case it > >>>>> went down to prevent PCI accesses from hanging the bus. Such accesses > >>>>> can happen early in the PCI resume process, in the resume_noirq, thus > >>>>> the link must be reestablished in the resume_noirq callback of the > >>>>> driver. > >>>> > >>>> This looks like a fix (most likely fixing initial S2R support, please > >>>> help me chase the commit ID), should we consider it for stable kernels ? > >>>> > >>>> Without it I understand S2R is actually broken on platforms with this > >>>> host bridge. > >>> I don't think this ever worked, so it's hard to find a Fixes: commit for > >>> this. > >> > >> If we want to send it to stable kernels we have to select which versions > >> we are covering. I think the only options for a Fixes: tag are either > >> the initial S2R support commit for the platforms this driver runs on > >> or the initial driver commit that harks back to v3.16 AFAICS. > > > > This only started to become an issue when support for arm64 platforms > > was added, where PSCI may power down the SoC, right? > > Wouldn't you also hit this on ARM32 LPAE ones ? This is about the PCI link issue on system resume, right? > > Hence: > > Fixes: e015f88c368da1e6 ("PCI: rcar: Add support for R-Car H3 to pcie-rcar") Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds