From patchwork Fri Jul 1 03:25:31 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hongxing Zhu X-Patchwork-Id: 12902619 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 AA745C433EF for ; Fri, 1 Jul 2022 03:40:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232870AbiGADkh (ORCPT ); Thu, 30 Jun 2022 23:40:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234167AbiGADkc (ORCPT ); Thu, 30 Jun 2022 23:40:32 -0400 Received: from inva021.nxp.com (inva021.nxp.com [92.121.34.21]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8472F65D5A; Thu, 30 Jun 2022 20:40:31 -0700 (PDT) Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 1CECD201153; Fri, 1 Jul 2022 05:40:30 +0200 (CEST) Received: from aprdc01srsp001v.ap-rdc01.nxp.com (aprdc01srsp001v.ap-rdc01.nxp.com [165.114.16.16]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id DB1D32035BC; Fri, 1 Jul 2022 05:40:29 +0200 (CEST) Received: from localhost.localdomain (shlinux2.ap.freescale.net [10.192.224.44]) by aprdc01srsp001v.ap-rdc01.nxp.com (Postfix) with ESMTP id 4B75D1802204; Fri, 1 Jul 2022 11:40:28 +0800 (+08) From: Richard Zhu To: l.stach@pengutronix.de, bhelgaas@google.com, robh+dt@kernel.org, broonie@kernel.org, lorenzo.pieralisi@arm.com, festevam@gmail.com, francesco.dolcini@toradex.com Cc: hongxing.zhu@nxp.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de, linux-imx@nxp.com Subject: [PATCH v14 13/17] PCI: imx6: Reduce resume time by only starting link if it was up before suspend Date: Fri, 1 Jul 2022 11:25:31 +0800 Message-Id: <1656645935-1370-14-git-send-email-hongxing.zhu@nxp.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1656645935-1370-1-git-send-email-hongxing.zhu@nxp.com> References: <1656645935-1370-1-git-send-email-hongxing.zhu@nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Because i.MX PCIe doesn't support hot-plug feature. In the link down scenario, only start the PCIe link training in resume when the link is up before system suspend to avoid the long latency in the link training period. Signed-off-by: Richard Zhu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/dwc/pci-imx6.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index e236f824c808..5a06fbca82d6 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -67,6 +67,7 @@ struct imx6_pcie { struct dw_pcie *pci; int reset_gpio; bool gpio_active_high; + bool link_is_up; struct clk *pcie_bus; struct clk *pcie_phy; struct clk *pcie_inbound_axi; @@ -881,11 +882,13 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) dev_info(dev, "Link: Gen2 disabled\n"); } + imx6_pcie->link_is_up = true; tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA); dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS); return 0; err_reset_phy: + imx6_pcie->link_is_up = false; 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)); @@ -1032,9 +1035,8 @@ static int imx6_pcie_resume_noirq(struct device *dev) return ret; dw_pcie_setup_rc(pp); - ret = imx6_pcie_start_link(imx6_pcie->pci); - if (ret < 0) - dev_info(dev, "pcie link is down after resume.\n"); + if (imx6_pcie->link_is_up) + imx6_pcie_start_link(imx6_pcie->pci); return 0; }