From patchwork Mon Nov 1 06:17:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Zhu X-Patchwork-Id: 12595937 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F206C433F5 for ; Mon, 1 Nov 2021 06:44:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0825C60F4F for ; Mon, 1 Nov 2021 06:44:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231213AbhKAGqs (ORCPT ); Mon, 1 Nov 2021 02:46:48 -0400 Received: from inva021.nxp.com ([92.121.34.21]:45542 "EHLO inva021.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230520AbhKAGqn (ORCPT ); Mon, 1 Nov 2021 02:46:43 -0400 Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 4A0C5201219; Mon, 1 Nov 2021 07:44:09 +0100 (CET) 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 DCBF7201217; Mon, 1 Nov 2021 07:44:08 +0100 (CET) Received: from localhost.localdomain (shlinux2.ap.freescale.net [10.192.224.44]) by aprdc01srsp001v.ap-rdc01.nxp.com (Postfix) with ESMTP id 253B8183ACDC; Mon, 1 Nov 2021 14:44:05 +0800 (+08) From: Richard Zhu To: l.stach@pengutronix.de, bhelgaas@google.com, broonie@kernel.org, lorenzo.pieralisi@arm.com, jingoohan1@gmail.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, Richard Zhu Subject: [PATCH v4 6/6] PCI: imx6: Add the compliance tests mode support Date: Mon, 1 Nov 2021 14:17:58 +0800 Message-Id: <1635747478-25562-7-git-send-email-hongxing.zhu@nxp.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1635747478-25562-1-git-send-email-hongxing.zhu@nxp.com> References: <1635747478-25562-1-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 Refer to the system board signal Quality of PCIe archiecture PHY test specification. Signal quality tests(for example: jitters, differential eye opening and so on ) can be executed with devices in the polling.compliance state. To let the device support polling.compliance stat, the clocks and powers shouldn't be turned off when the probe of device driver is failed. Based on CLB(Compliance Load Board) Test Fixture and so on test equipments, the PHY link would be down during the compliance tests. Refer to this scenario, add the i.MX PCIe compliance tests mode enable support, and keep the clocks and powers on, and finish the driver probe without error return. Use the "pci_imx6.compliance=1" in kernel command line to enable the compliance tests mode. Signed-off-by: Richard Zhu --- drivers/pci/controller/dwc/pci-imx6.c | 33 +++++++++++++++++++-------- 1 file changed, 24 insertions(+), 9 deletions(-) diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index 8be4b8a9b564..d6769f95ca4e 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -143,6 +143,10 @@ struct imx6_pcie { #define PHY_RX_OVRD_IN_LO_RX_DATA_EN BIT(5) #define PHY_RX_OVRD_IN_LO_RX_PLL_EN BIT(3) +static bool imx6_pcie_cmp_mode; +module_param_named(compliance, imx6_pcie_cmp_mode, bool, 0644); +MODULE_PARM_DESC(compliance, "i.MX PCIe compliance test mode (1=compliance test mode enabled)"); + static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, bool exp_val) { struct dw_pcie *pci = imx6_pcie->pci; @@ -802,10 +806,12 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) * started in Gen2 mode, there is a possibility the devices on the * bus will not be detected at all. This happens with PCIe switches. */ - tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP); - tmp &= ~PCI_EXP_LNKCAP_SLS; - tmp |= PCI_EXP_LNKCAP_SLS_2_5GB; - dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp); + if (!imx6_pcie_cmp_mode) { + tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP); + tmp &= ~PCI_EXP_LNKCAP_SLS; + tmp |= PCI_EXP_LNKCAP_SLS_2_5GB; + dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp); + } /* Start LTSSM. */ imx6_pcie_ltssm_enable(dev); @@ -893,10 +899,12 @@ static void imx6_pcie_host_exit(struct pcie_port *pp) struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); - imx6_pcie_reset_phy(imx6_pcie); - imx6_pcie_clk_disable(imx6_pcie); - if (imx6_pcie->vpcie) - regulator_disable(imx6_pcie->vpcie); + if (!imx6_pcie_cmp_mode) { + imx6_pcie_reset_phy(imx6_pcie); + imx6_pcie_clk_disable(imx6_pcie); + if (imx6_pcie->vpcie) + regulator_disable(imx6_pcie->vpcie); + } } static const struct dw_pcie_host_ops imx6_pcie_host_ops = { @@ -1182,8 +1190,15 @@ static int imx6_pcie_probe(struct platform_device *pdev) return ret; ret = dw_pcie_host_init(&pci->pp); - if (ret < 0) + if (ret < 0) { + if (imx6_pcie_cmp_mode) { + dev_info(dev, "Driver loaded with compliance test mode enabled.\n"); + ret = 0; + } else { + dev_err(dev, "Unable to add pcie port.\n"); + } return ret; + } if (pci_msi_enabled()) { u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);