From patchwork Sat May 6 07:31:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manivannan Sadhasivam X-Patchwork-Id: 679602 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 C2E33C77B7F for ; Sat, 6 May 2023 07:32:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231172AbjEFHcO (ORCPT ); Sat, 6 May 2023 03:32:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37688 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230028AbjEFHcG (ORCPT ); Sat, 6 May 2023 03:32:06 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0909D11629 for ; Sat, 6 May 2023 00:32:00 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id d2e1a72fcca58-6439b410679so1408858b3a.0 for ; Sat, 06 May 2023 00:32:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1683358319; x=1685950319; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=gnprX8nF58MbC+8jk2bB2WSCWcm3GNiHBCtxvPm30dM=; b=IEPLhW3VjIQfoKFoGZMwj/5mHPFXFTkjY7vlMGmonbbPkTlEr7EHa294tNa/LOpUqr pmk7r1njQJX+hZRxDuvFkiUqzHGKuHFBGTLrIWZar5Y2x99dd4LPAX549Pk9AqIao9jO ElBb3tmmEOgCGjY35nqnHgq6QOiCGRyf0ZSctdPfrSTWw2FyoZ5x2n9aDgY+0795eYC8 AFHCPWTVc3cITjYxELTXD7CLzyL4AUksfaiEyytWqTGnYPPuoqhX/KKoB9uZW/zcNCaH Jdx/ztme3QMugbBBKg76PrOq9WuO9XjJuqL5YRcNGlD3UXniPpSI9EvDos+dZFpn+iwO ZqJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683358319; x=1685950319; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=gnprX8nF58MbC+8jk2bB2WSCWcm3GNiHBCtxvPm30dM=; b=GxbMP2XrO3FS8gSQt0veS3mheAamWE9dE5KIWVCtMl2Rt+YAnvO03INPRp6hDXQk+S sffOFthkh+sV2O0Iw8+VKsOmMudkfU2ezpPqS+lc++Z8xjyDbvbd/cxSEm4mkC9lIQvm wysckmeNxnOb3WKOTkhX39b7ofR3IliDMtcHWwImtnHB3PTu00qKtU1zwlT/xrJABJBP yB956pZxLEkJESQZNEiSoCeJ+Q/qBzY8EMIWPa0zZzVfa+o1R0Lw7qY3KZ4DwYtE/nk5 aO6Cf0Ity4E+KbDG724UkGk6NPlDqFHuOc5tVMAjwvb7ma9TKSk7sEW7ToGqcIMQwnMg TNPg== X-Gm-Message-State: AC+VfDyrQ0Wgs1feLzFLumU3BLTf4NApHc0KY6W5nHHcxOKV/RaWY51w nraAgaew3mAlu2VfQpuegqRD X-Google-Smtp-Source: ACHHUZ4e+3o0zhkMKnSQOeDFtRGJYjyqM20YY/XUi3h/jE50P7TPO9rF8YGTiQip+KkHLiSSpVhGZA== X-Received: by 2002:a05:6a00:24cf:b0:63d:3411:f9e3 with SMTP id d15-20020a056a0024cf00b0063d3411f9e3mr5929321pfv.19.1683358319465; Sat, 06 May 2023 00:31:59 -0700 (PDT) Received: from localhost.localdomain ([120.138.12.87]) by smtp.gmail.com with ESMTPSA id z16-20020aa785d0000000b0062a56e51fd7sm2627373pfn.188.2023.05.06.00.31.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 06 May 2023 00:31:59 -0700 (PDT) From: Manivannan Sadhasivam To: lpieralisi@kernel.org, kw@linux.com, bhelgaas@google.com Cc: robh@kernel.org, andersson@kernel.org, konrad.dybcio@linaro.org, linux-pci@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, steev@kali.org, quic_srichara@quicinc.com, Manivannan Sadhasivam Subject: [PATCH 3/8] PCI: qcom: Do not advertise hotplug capability for IPs v2.7.0 and v1.9.0 Date: Sat, 6 May 2023 13:01:34 +0530 Message-Id: <20230506073139.8789-4-manivannan.sadhasivam@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230506073139.8789-1-manivannan.sadhasivam@linaro.org> References: <20230506073139.8789-1-manivannan.sadhasivam@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org SoCs making use of Qcom PCIe controller IPs v2.7.0 and v1.9.0 do not support hotplug functionality. But the hotplug capability bit is set by default in the hardware. This causes the kernel PCI core to register hotplug service for the controller and send hotplug commands to it. But those commands will timeout generating messages as below during boot and suspend/resume. [ 5.782159] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x03c0 (issued 2020 msec ago) [ 5.810161] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x03c0 (issued 2048 msec ago) [ 7.838162] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x07c0 (issued 2020 msec ago) [ 7.870159] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x07c0 (issued 2052 msec ago) This not only spams the console output but also induces a delay of a couple of seconds. To fix this issue, let's clear the HPC bit in PCI_EXP_SLTCAP register as a part of the post init sequence to not advertise the hotplug capability for the controller. Signed-off-by: Manivannan Sadhasivam --- drivers/pci/controller/dwc/pcie-qcom.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c index 391a45d1e70a..00246726c21d 100644 --- a/drivers/pci/controller/dwc/pcie-qcom.c +++ b/drivers/pci/controller/dwc/pcie-qcom.c @@ -966,6 +966,23 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie) return ret; } +static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie) +{ + struct dw_pcie *pci = pcie->pci; + u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP); + u32 val; + + dw_pcie_dbi_ro_wr_en(pci); + + val = readl(pci->dbi_base + offset + PCI_EXP_SLTCAP); + val &= ~PCI_EXP_SLTCAP_HPC; + writel(val, pci->dbi_base + offset + PCI_EXP_SLTCAP); + + dw_pcie_dbi_ro_wr_dis(pci); + + return 0; +} + static void qcom_pcie_deinit_2_7_0(struct qcom_pcie *pcie) { struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0; @@ -1272,6 +1289,7 @@ static const struct qcom_pcie_ops ops_2_3_3 = { static const struct qcom_pcie_ops ops_2_7_0 = { .get_resources = qcom_pcie_get_resources_2_7_0, .init = qcom_pcie_init_2_7_0, + .post_init = qcom_pcie_post_init_2_7_0, .deinit = qcom_pcie_deinit_2_7_0, .ltssm_enable = qcom_pcie_2_3_2_ltssm_enable, }; @@ -1280,6 +1298,7 @@ static const struct qcom_pcie_ops ops_2_7_0 = { static const struct qcom_pcie_ops ops_1_9_0 = { .get_resources = qcom_pcie_get_resources_2_7_0, .init = qcom_pcie_init_2_7_0, + .post_init = qcom_pcie_post_init_2_7_0, .deinit = qcom_pcie_deinit_2_7_0, .ltssm_enable = qcom_pcie_2_3_2_ltssm_enable, .config_sid = qcom_pcie_config_sid_1_9_0,