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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 56FA1C433C1 for ; Fri, 26 Mar 2021 09:42:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1374B61A3F for ; Fri, 26 Mar 2021 09:42:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229730AbhCZJmF (ORCPT ); Fri, 26 Mar 2021 05:42:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229622AbhCZJlj (ORCPT ); Fri, 26 Mar 2021 05:41:39 -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 6AFE3C0613AA for ; Fri, 26 Mar 2021 02:41:39 -0700 (PDT) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=[IPv6:::1]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lPiyD-0007tw-Uh; Fri, 26 Mar 2021 10:41:34 +0100 Message-ID: <5b376408a9521298dc289467f15bf6dc338cac6c.camel@pengutronix.de> Subject: Re: [PATCH v3 3/3] PCI: imx: clear vreg bypass when pcie vph voltage is 3v3 From: Lucas Stach To: Richard Zhu , andrew.smirnov@gmail.com, shawnguo@kernel.org, kw@linux.com, bhelgaas@google.com, stefan@agner.ch, lorenzo.pieralisi@arm.com Cc: linux-pci@vger.kernel.org, linux-imx@nxp.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de Date: Fri, 26 Mar 2021 10:41:32 +0100 In-Reply-To: <1616661882-26487-4-git-send-email-hongxing.zhu@nxp.com> References: <1616661882-26487-1-git-send-email-hongxing.zhu@nxp.com> <1616661882-26487-4-git-send-email-hongxing.zhu@nxp.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: l.stach@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-pci@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Am Donnerstag, dem 25.03.2021 um 16:44 +0800 schrieb Richard Zhu: > Both 1.8v and 3.3v power supplies can be used by i.MX8MQ PCIe PHY. > In default, the PCIE_VPH voltage is suggested to be 1.8v refer to data > sheet. When PCIE_VPH is supplied by 3.3v in the HW schematic design, > the VREG_BYPASS bits of GPR registers should be cleared from default > value 1b'1 to 1b'0. Thus, the internal 3v3 to 1v8 translator would be > turned on. > > Signed-off-by: Richard Zhu Reviewed-by: Lucas Stach > --- >  drivers/pci/controller/dwc/pci-imx6.c | 20 ++++++++++++++++++++ >  1 file changed, 20 insertions(+) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index 853ea8e82952..d9d534f0840f 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -37,6 +37,7 @@ >  #define IMX8MQ_GPR_PCIE_REF_USE_PAD BIT(9) >  #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN BIT(10) >  #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE BIT(11) > +#define IMX8MQ_GPR_PCIE_VREG_BYPASS BIT(12) >  #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE GENMASK(11, 8) >  #define IMX8MQ_PCIE2_BASE_ADDR 0x33c00000 >   > > > > @@ -80,6 +81,7 @@ struct imx6_pcie { >   u32 tx_swing_full; >   u32 tx_swing_low; >   struct regulator *vpcie; > + struct regulator *vph; >   void __iomem *phy_base; >   > > > >   /* power domain for pcie */ > @@ -621,6 +623,17 @@ static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie) >   imx6_pcie_grp_offset(imx6_pcie), >   IMX8MQ_GPR_PCIE_REF_USE_PAD, >   IMX8MQ_GPR_PCIE_REF_USE_PAD); > + /* > + * Regarding to the datasheet, the PCIE_VPH is suggested > + * to be 1.8V. If the PCIE_VPH is supplied by 3.3V, the > + * VREG_BYPASS should be cleared to zero. > + */ > + if (imx6_pcie->vph && > + regulator_get_voltage(imx6_pcie->vph) > 3000000) > + regmap_update_bits(imx6_pcie->iomuxc_gpr, > + imx6_pcie_grp_offset(imx6_pcie), > + IMX8MQ_GPR_PCIE_VREG_BYPASS, > + 0); >   break; >   case IMX7D: >   regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > @@ -1130,6 +1143,13 @@ static int imx6_pcie_probe(struct platform_device *pdev) >   imx6_pcie->vpcie = NULL; >   } >   > > > > + imx6_pcie->vph = devm_regulator_get_optional(&pdev->dev, "vph"); > + if (IS_ERR(imx6_pcie->vph)) { > + if (PTR_ERR(imx6_pcie->vph) != -ENODEV) > + return PTR_ERR(imx6_pcie->vph); > + imx6_pcie->vph = NULL; > + } > + >   platform_set_drvdata(pdev, imx6_pcie); >   > > > >   ret = imx6_pcie_attach_pd(dev);