From patchwork Thu Jul 14 07:31:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hongxing Zhu X-Patchwork-Id: 12917402 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 0D4FFC433EF for ; Thu, 14 Jul 2022 07:48:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237661AbiGNHsA (ORCPT ); Thu, 14 Jul 2022 03:48:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43326 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237562AbiGNHrY (ORCPT ); Thu, 14 Jul 2022 03:47:24 -0400 Received: from inva020.nxp.com (inva020.nxp.com [92.121.34.13]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 345C533E38; Thu, 14 Jul 2022 00:47:11 -0700 (PDT) Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id B7E511A2049; Thu, 14 Jul 2022 09:47:09 +0200 (CEST) Received: from aprdc01srsp001v.ap-rdc01.nxp.com (aprdc01srsp001v.ap-rdc01.nxp.com [165.114.16.16]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 7D17D1A2056; Thu, 14 Jul 2022 09:47:09 +0200 (CEST) Received: from localhost.localdomain (shlinux2.ap.freescale.net [10.192.224.44]) by aprdc01srsp001v.ap-rdc01.nxp.com (Postfix) with ESMTP id D4B06180222A; Thu, 14 Jul 2022 15:47:07 +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 v15 13/17] PCI: imx6: Reduce resume time by only starting link if it was up before suspend Date: Thu, 14 Jul 2022 15:31:05 +0800 Message-Id: <1657783869-19194-14-git-send-email-hongxing.zhu@nxp.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1657783869-19194-1-git-send-email-hongxing.zhu@nxp.com> References: <1657783869-19194-1-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 i.MX PCIe doesn't support hotplug. During resume, only start PCIe link training when the link was up before system suspend to avoid the long latency in the link training period. [bhelgaas: imx6_pcie_start_link() return value check removal moved to previous patch, pointed out by Lucas Stach ] Link: https://lore.kernel.org/r/1656645935-1370-14-git-send-email-hongxing.zhu@nxp.com Signed-off-by: Richard Zhu Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/dwc/pci-imx6.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index 3ac4f2aa91c5..ad0933c3dc70 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)); @@ -1032,7 +1035,9 @@ static int imx6_pcie_resume_noirq(struct device *dev) return ret; dw_pcie_setup_rc(pp); - imx6_pcie_start_link(imx6_pcie->pci); + if (imx6_pcie->link_is_up) + imx6_pcie_start_link(imx6_pcie->pci); + return 0; } #endif