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 74A5CC433EF for ; Tue, 8 Feb 2022 11:31:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359473AbiBHLbh (ORCPT ); Tue, 8 Feb 2022 06:31:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356096AbiBHKJx (ORCPT ); Tue, 8 Feb 2022 05:09:53 -0500 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE13CC03FEC0; Tue, 8 Feb 2022 02:09:51 -0800 (PST) Received: by mail-ed1-x529.google.com with SMTP id u18so36010057edt.6; Tue, 08 Feb 2022 02:09:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=6I/rjvse3Om/FLStiyJ4zPHHDV5qURCXK6IN/dDjA2Y=; b=OYMgQRtALhGTq0ZaHfcxxyRrbOb5s3iySIWCA/41PPc2smh+40ANGf02xr7BdvKXXb 9AeaYlj9rC7eC/amw02RLD0FBYilOZDTW6C18E6/HzUinOMBfe5bN+nkveyL1CyKG+lR NUXzjEMWQU3+xBDw7ApVQ2V+jpdW+uibiTerLaLHSXEz/MwhCA7pkdwKgLUmOAIk2bpU J2BEWUPXCp0C6n/FMqvrh2JTkWJWyN2xL8Si+TBcYXmPTcUv1RUpGnFKL1zzSx2n5SS8 /JyKLnHvesc0AZ2Ndx4q6HyoWlKoWWL/TswFPEyglorBm/5ZomuMIiWZVBDDFCpHb1An C2wA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=6I/rjvse3Om/FLStiyJ4zPHHDV5qURCXK6IN/dDjA2Y=; b=7Po3QKdtE0Buafj58pXdPXoyV4yNCicYTCUZrFwQSga8QYljD+QQ1KeqJ75u/PkKtE NjQpL/RDOafpMBIhhHQXRawesCpGh2yHxLZe8FsuuscdaxKSE9ReaH6K9eIvJwLmxOIr c3EBH5t9oBYMili1iyiRuocR3MmJQS8Nya78tEnLVGgqsxqHvffmn3LKM08foBsSCCHK gtFcuua8+A02iKJK59wdbHvrGBEpekk+NVAMwPS49fK0U5z77l+66w1VxXDwtdtAcjHJ iO5O9r9iVJhqgAfjY2bXBFKbe3ogZgPRvk1Gu/Q+J8Xukgypd8itKLzBI85CpCV2iqc/ oZoQ== X-Gm-Message-State: AOAM530o3YBbouKKDvb+BS3JGwwhM62AjPjrJ1pqWn+D3BYU1EChUMg2 amIzJ7G3+L1/fwLgENNanrAE8u/uEhypBklmtHE= X-Google-Smtp-Source: ABdhPJxPKmtRUfGotwhepo8jmbA/Aggq6CASzSYHu7p78ImQqYjC93TuyPlPIPb3l6JBNgwAmzA4p2tLFIf9PS34qIg= X-Received: by 2002:aa7:dd0b:: with SMTP id i11mr3621700edv.81.1644314990255; Tue, 08 Feb 2022 02:09:50 -0800 (PST) MIME-Version: 1.0 References: <1644290735-3797-1-git-send-email-hongxing.zhu@nxp.com> <1644290735-3797-8-git-send-email-hongxing.zhu@nxp.com> In-Reply-To: <1644290735-3797-8-git-send-email-hongxing.zhu@nxp.com> From: Fabio Estevam Date: Tue, 8 Feb 2022 07:09:40 -0300 Message-ID: Subject: Re: [PATCH v6 7/8] PCI: imx6: Disable enabled clocks and regulators after link is down To: Richard Zhu Cc: Lucas Stach , Bjorn Helgaas , Mark Brown , Lorenzo Pieralisi , Jingoo Han , linux-pci@vger.kernel.org, NXP Linux Team , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , linux-kernel , Sascha Hauer Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Richard, On Tue, Feb 8, 2022 at 12:57 AM Richard Zhu wrote: > > Since i.MX PCIe doesn't support the hot-plug, and to save power > consumption as much as possible. Return error and disable the enabled > clocks and regulators when link is down,. It is OK to disable clocks and regulators, but I don't think we should return an error on dw_pcie_wait_for_link() failure. Please check: https://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/pci.git/commit/?h=pci/imx6&id=f81f095e87715e198471f4653952fe5e3f824874 and https://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/pci.git/commit/?h=pci/imx6&id=886a9c134755 as to why all the dwc PCI drivers should treat dw_pcie_wait_for_link() uniformly. > > Add a new host_exit() callback for i.MX PCIe driver to disable the > enabled clocks, regulators and so on in the error handling after > host_init is finished. > > Signed-off-by: Richard Zhu > --- > drivers/pci/controller/dwc/pci-imx6.c | 30 ++++++++++++++++++++++++--- > 1 file changed, 27 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index e165ad00989c..7a7d9204c6bc 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -848,7 +848,9 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) > /* Start LTSSM. */ > imx6_pcie_ltssm_enable(dev); > > - dw_pcie_wait_for_link(pci); > + ret = dw_pcie_wait_for_link(pci); > + if (ret) > + goto err_reset_phy; > > if (pci->link_gen == 2) { > /* Allow Gen2 mode after the link is up. */ > @@ -884,7 +886,9 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) > } > > /* Make sure link training is finished as well! */ > - dw_pcie_wait_for_link(pci); > + ret = dw_pcie_wait_for_link(pci); > + if (ret) > + goto err_reset_phy; > } else { > dev_info(dev, "Link: Gen2 disabled\n"); > } > @@ -897,7 +901,6 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) > dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n", > dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0), > dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1)); > - imx6_pcie_reset_phy(imx6_pcie); > return ret; > } > > @@ -921,8 +924,29 @@ static int imx6_pcie_host_init(struct pcie_port *pp) > return 0; > } > > +static void imx6_pcie_host_exit(struct pcie_port *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct device *dev = pci->dev; > + struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); > + > + imx6_pcie_reset_phy(imx6_pcie); > + imx6_pcie_clk_disable(imx6_pcie); > + switch (imx6_pcie->drvdata->variant) { > + case IMX8MM: > + if (phy_power_off(imx6_pcie->phy)) > + dev_err(dev, "unable to power off phy\n"); > + break; > + default: > + break; > + } > + if (imx6_pcie->vpcie) > + regulator_disable(imx6_pcie->vpcie); > +} > + > static const struct dw_pcie_host_ops imx6_pcie_host_ops = { > .host_init = imx6_pcie_host_init, > + .host_exit = imx6_pcie_host_exit, > }; > > static const struct dw_pcie_ops dw_pcie_ops = { > -- > 2.25.1 >