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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 E7124C10F06 for ; Thu, 28 Mar 2019 14:18:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD82B217D7 for ; Thu, 28 Mar 2019 14:18:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553782706; bh=tQCGp2wAo5O5h2JoFX7D0l6D6ldwpImuPbCDO0cSRTY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=hk5gLCafRlQYObkIgMdRjARD83/28HFltXO1jYJbeubQzAvBaSrgiuya1YzaYJsSK vHdN39RzD1S9G6E3djbyNCMAt6yf0a1m+xA9n2EtAdbTVgYNUJPfyYZg6M5ES+wtRO fa7oVi6xP2erzzxDtcfCOKvaeyd+tZJcP6sdT7Ss= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726171AbfC1OSZ (ORCPT ); Thu, 28 Mar 2019 10:18:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:39866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726076AbfC1OSZ (ORCPT ); Thu, 28 Mar 2019 10:18:25 -0400 Received: from localhost (173-25-63-173.client.mchsi.com [173.25.63.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A62C72075E; Thu, 28 Mar 2019 14:18:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553782703; bh=tQCGp2wAo5O5h2JoFX7D0l6D6ldwpImuPbCDO0cSRTY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rYRU141kixe1TjaGq332ay3WtbOJxKWSQeeyZfFmRFEMaAOT0/5oPs/uuQ5/9ylEl H6W4S7/TAvfxGvNPsumTGlTItsPK5KrR6U8S2oMmlGxCHf3/U/IWHTU0jW8ArjcN3r VCLBjVphHMzjzBRf2zUEXn7tIHl5iKrHTfXE64Wk= Date: Thu, 28 Mar 2019 09:18:22 -0500 From: Bjorn Helgaas To: marek.vasut@gmail.com Cc: linux-pci@vger.kernel.org, Kazufumi Ikeda , Gaku Inami , Marek Vasut , Lorenzo Pieralisi , Simon Horman , Wolfram Sang , stable@vger.kernel.org, Geert Uytterhoeven , Phil Edworthy , Wolfram Sang , linux-renesas-soc@vger.kernel.org Subject: Re: [PATCH V3] PCI: rcar: Add the initialization of PCIe link in resume_noirq() Message-ID: <20190328141822.GA156243@google.com> References: <20190325194319.12850-1-marek.vasut@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190325194319.12850-1-marek.vasut@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, Mar 25, 2019 at 08:43:19PM +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, as early as the > SUSPEND_RESUME_NOIRQ step, thus the link must be reestablished in the > driver resume_noirq() callback. > > Fixes: e015f88c368d ("PCI: rcar: Add support for R-Car H3 to pcie-rcar") I'm fine with the fix itself, but since e015f88c368d appeared more than two years ago in v4.5, the justification for merging this after the merge window is a little weak. Is there a more recent change that exposed this problem? The usual situation is that we merged something during the v5.1 merge window that caused a regression, and we're now fixing that before v5.1 final. Bjorn > Signed-off-by: Kazufumi Ikeda > Signed-off-by: Gaku Inami > Signed-off-by: Marek Vasut > [lorenzo.pieralisi@arm.com: reformatted commit log] > Signed-off-by: Lorenzo Pieralisi > Reviewed-by: Simon Horman > Acked-by: Wolfram Sang > Cc: stable@vger.kernel.org > Cc: Geert Uytterhoeven > Cc: Phil Edworthy > Cc: Simon Horman > Cc: Wolfram Sang > Cc: linux-renesas-soc@vger.kernel.org > --- > V2: - Use BIT() macro for (1 << n) > - Since polling in rcar_pcie_wait_for_dl() uses udelay(), do not > add extra changes to this function anymore > - Make resume_noirq return early and clean up parenthesis therein > V3: - Add missing PMSR register definition, dropped due to patch reshuffling > --- > drivers/pci/controller/pcie-rcar.c | 21 +++++++++++++++++++++ > 1 file changed, 21 insertions(+) > > diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c > index c8febb009454..6a4e435bd35f 100644 > --- a/drivers/pci/controller/pcie-rcar.c > +++ b/drivers/pci/controller/pcie-rcar.c > @@ -46,6 +46,7 @@ > > /* Transfer control */ > #define PCIETCTLR 0x02000 > +#define DL_DOWN BIT(3) > #define CFINIT 1 > #define PCIETSTR 0x02004 > #define DATA_LINK_ACTIVE 1 > @@ -94,6 +95,7 @@ > #define MACCTLR 0x011058 > #define SPEED_CHANGE BIT(24) > #define SCRAMBLE_DISABLE BIT(27) > +#define PMSR 0x01105c > #define MACS2R 0x011078 > #define MACCGSPSETR 0x011084 > #define SPCNGRSN BIT(31) > @@ -1130,6 +1132,7 @@ static int rcar_pcie_probe(struct platform_device *pdev) > pcie = pci_host_bridge_priv(bridge); > > pcie->dev = dev; > + platform_set_drvdata(pdev, pcie); > > err = pci_parse_request_of_pci_ranges(dev, &pcie->resources, NULL); > if (err) > @@ -1221,10 +1224,28 @@ static int rcar_pcie_probe(struct platform_device *pdev) > return err; > } > > +static int rcar_pcie_resume_noirq(struct device *dev) > +{ > + struct rcar_pcie *pcie = dev_get_drvdata(dev); > + > + if (rcar_pci_read_reg(pcie, PMSR) && > + !(rcar_pci_read_reg(pcie, PCIETCTLR) & DL_DOWN)) > + return 0; > + > + /* Re-establish the PCIe link */ > + rcar_pci_write_reg(pcie, CFINIT, PCIETCTLR); > + return rcar_pcie_wait_for_dl(pcie); > +} > + > +static const struct dev_pm_ops rcar_pcie_pm_ops = { > + .resume_noirq = rcar_pcie_resume_noirq, > +}; > + > static struct platform_driver rcar_pcie_driver = { > .driver = { > .name = "rcar-pcie", > .of_match_table = rcar_pcie_of_match, > + .pm = &rcar_pcie_pm_ops, > .suppress_bind_attrs = true, > }, > .probe = rcar_pcie_probe, > -- > 2.20.1 >