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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 BD078C6778A for ; Tue, 24 Jul 2018 16:55:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7CDBB20856 for ; Tue, 24 Jul 2018 16:55:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7CDBB20856 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388451AbeGXSDQ (ORCPT ); Tue, 24 Jul 2018 14:03:16 -0400 Received: from metis.ext.pengutronix.de ([85.220.165.71]:39565 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388403AbeGXSDP (ORCPT ); Tue, 24 Jul 2018 14:03:15 -0400 Received: from kresse.hi.pengutronix.de ([2001:67c:670:100:1d::2a]) by metis.ext.pengutronix.de with esmtp (Exim 4.89) (envelope-from ) id 1fi0b8-0000aj-6j; Tue, 24 Jul 2018 18:55:42 +0200 Message-ID: <1532451341.32306.9.camel@pengutronix.de> Subject: Re: [PATCH v3 2/2] PCI: imx: Initial imx7d pm support From: Lucas Stach To: Leonard Crestez , Andrey Smirnov , Richard Zhu , Shawn Guo Cc: Anson Huang , Philipp Zabel , Bjorn Helgaas , Jingoo Han , Joao Pinto , Lorenzo Pieralisi , Fabio Estevam , Dong Aisheng , linux-imx@nxp.com, kernel@pengutronix.de, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Date: Tue, 24 Jul 2018 18:55:41 +0200 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1+deb9u1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::2a 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-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Dienstag, den 24.07.2018, 19:14 +0300 schrieb Leonard Crestez: > On imx7d the pcie-phy power domain is turned off in suspend and this can > make the system hang after resume when attempting any read from PCI. > > Fix this by adding minimal suspend/resume code from the nxp internal > tree. This will prepare for powering down on suspend and reset the block > on resume. > > Code is only for imx7d but a very similar sequence can be used for > other socs. > > > The original author is mostly Richard Zhu , this > patch adjusts the code to the upstream imx7d implemention using reset > controls and power domains. > > Signed-off-by: Leonard Crestez Reviewed-by: Lucas Stach > --- >  drivers/pci/controller/dwc/pci-imx6.c | 97 +++++++++++++++++++++++++-- >  1 file changed, 92 insertions(+), 5 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index 4a9a673b4777..65b6d1015723 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -540,10 +540,28 @@ static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie) >   > >   dev_err(dev, "Speed change timeout\n"); > >   return -EINVAL; >  } >   > +static void imx6_pcie_ltssm_enable(struct device *dev) > +{ > > + struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); > + > > + switch (imx6_pcie->variant) { > > + case IMX6Q: > > + case IMX6SX: > > + case IMX6QP: > > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > > +    IMX6Q_GPR12_PCIE_CTL_2, > > +    IMX6Q_GPR12_PCIE_CTL_2); > > + break; > > + case IMX7D: > > + reset_control_deassert(imx6_pcie->apps_reset); > > + break; > > + } > +} > + >  static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) >  { > >   struct dw_pcie *pci = imx6_pcie->pci; > >   struct device *dev = pci->dev; > >   u32 tmp; > @@ -558,15 +576,11 @@ static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie) > >   tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK; > >   tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1; > >   dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp); >   > >   /* Start LTSSM. */ > > - if (imx6_pcie->variant == IMX7D) > > - reset_control_deassert(imx6_pcie->apps_reset); > > - else > > - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > > -    IMX6Q_GPR12_PCIE_CTL_2, 1 << 10); > > + imx6_pcie_ltssm_enable(dev); >   > >   ret = imx6_pcie_wait_for_link(imx6_pcie); > >   if (ret) > >   goto err_reset_phy; >   > @@ -680,10 +694,82 @@ static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, >   >  static const struct dw_pcie_ops dw_pcie_ops = { > >   .link_up = imx6_pcie_link_up, >  }; >   > +#ifdef CONFIG_PM_SLEEP > +static void imx6_pcie_ltssm_disable(struct device *dev) > +{ > > + struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); > + > > + switch (imx6_pcie->variant) { > > + case IMX6SX: > > + case IMX6QP: > > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > > +    IMX6Q_GPR12_PCIE_CTL_2, 0); > > + break; > > + case IMX7D: > > + reset_control_assert(imx6_pcie->apps_reset); > > + break; > > + default: > > + dev_err(dev, "ltssm_disable not supported\n"); > > + } > +} > + > +static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie) > +{ > > + clk_disable_unprepare(imx6_pcie->pcie); > > + clk_disable_unprepare(imx6_pcie->pcie_phy); > > + clk_disable_unprepare(imx6_pcie->pcie_bus); > + > > + if (imx6_pcie->variant == IMX7D) { > > + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, > > +    IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, > > +    IMX7D_GPR12_PCIE_PHY_REFCLK_SEL); > > + } > +} > + > +static int imx6_pcie_suspend_noirq(struct device *dev) > +{ > > + struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); > + > > + if (imx6_pcie->variant != IMX7D) > > + return 0; > + > > + imx6_pcie_clk_disable(imx6_pcie); > > + imx6_pcie_ltssm_disable(dev); > + > > + return 0; > +} > + > +static int imx6_pcie_resume_noirq(struct device *dev) > +{ > > + int ret; > > + struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev); > > + struct pcie_port *pp = &imx6_pcie->pci->pp; > + > > + if (imx6_pcie->variant != IMX7D) > > + return 0; > + > > + imx6_pcie_assert_core_reset(imx6_pcie); > > + imx6_pcie_init_phy(imx6_pcie); > > + imx6_pcie_deassert_core_reset(imx6_pcie); > > + dw_pcie_setup_rc(pp); > + > > + ret = imx6_pcie_establish_link(imx6_pcie); > > + if (ret < 0) > > + dev_info(dev, "pcie link is down after resume.\n"); > + > > + return 0; > +} > +#endif > + > +static const struct dev_pm_ops imx6_pcie_pm_ops = { > > + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq, > > +       imx6_pcie_resume_noirq) > +}; > + >  static int imx6_pcie_probe(struct platform_device *pdev) >  { > >   struct device *dev = &pdev->dev; > >   struct dw_pcie *pci; > >   struct imx6_pcie *imx6_pcie; > @@ -846,10 +932,11 @@ static const struct of_device_id imx6_pcie_of_match[] = { >  static struct platform_driver imx6_pcie_driver = { > >   .driver = { > > >   .name = "imx6q-pcie", > >   .of_match_table = imx6_pcie_of_match, > >   .suppress_bind_attrs = true, > > + .pm = &imx6_pcie_pm_ops, > >   }, > >   .probe    = imx6_pcie_probe, > >   .shutdown = imx6_pcie_shutdown, >  }; >