From nobody Wed Feb 11 18:05:37 2026 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 B24ECC77B7F for ; Sat, 6 May 2023 07:33:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231825AbjEFHdJ (ORCPT ); Sat, 6 May 2023 03:33:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231510AbjEFHcj (ORCPT ); Sat, 6 May 2023 03:32:39 -0400 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE0EB11613 for ; Sat, 6 May 2023 00:32:19 -0700 (PDT) Received: by mail-pf1-x42a.google.com with SMTP id d2e1a72fcca58-6434e263962so2035365b3a.2 for ; Sat, 06 May 2023 00:32:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1683358338; x=1685950338; 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=+zAQtr5L4Bacr5B+5i29IgpdXCjszEPez4niVXikONQ=; b=wFH50Le/fmj4VFIj5E1ssn8UqO1UF/RgItUl8Ehkil1aR1oKGwi6jXvtdYOToJXE3r hPA9OvKYf9OGiXOZhCNaEbN9iohK87X74Oja/lyvHOZ/ctJKzU8ZzuHcp+zTZ3MIqgwc wZUyvPKfY5JXwjc1pOtVBd1+0wy6d7UlGBRdQpeT8WeuuCNXfY0ZWTlzP2RvgHEWeU2X JlPs68wMooNWK3vCjZRCI9umNG7+sgcTxraJde1qMguztx5qYRqKma+4V0E9qiXgIo/d QTU6WSw1lXq5FbF7Hi6q61rjFvGSz89PQ8lPpvRyu+UMgWMc5m97z/UueFj02OhvdCe8 FhJw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683358338; x=1685950338; 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=+zAQtr5L4Bacr5B+5i29IgpdXCjszEPez4niVXikONQ=; b=hV4pKu1Sdw9jYA1nOgf+INZqrTmCRw9qBocRtVvs/X1oS8R8B/vZkjxvcb1SsU89nB 7Nl4vy72JcJEK+6e+kGM3Eg6EnXAThC31zj1JwXzLnnIXrGdd+Dm+ZVn+mI+MSE/R43I i/j5GYQ3i0JoATRiOPg2bdIRI3jENWNKMTk52yitQTglsHpO8Ktyl65B1Ufuf4GlCfAQ gZSebdTRvlmQKFLyHm4/0hNODP1YR2hMClCYYk9DCJFxGHKTWcknEgJqZO/sUhFw2Avp k/w/o6RRun16NkVkki1lH+LhrnWeWnamQDe2nWmXN+J0vAgaeRJINnqAhLGJRg2YEU64 k7GQ== X-Gm-Message-State: AC+VfDz2mMXrUWqUHhEDEoYHroiJH37FAeDAxudL2v4ng+DRnAGcTx7I +LizyzNHYIMkpAvNnfS9W9nY X-Google-Smtp-Source: ACHHUZ5qcx9XvDHw8oJ/vjG0RfbrlAlD7KlYkZZ2mdQ3Z9TvV0vgD+Xn6mfSyl6YYSRdBqLK4dRXvQ== X-Received: by 2002:a05:6a00:1ad0:b0:63b:5f78:d6db with SMTP id f16-20020a056a001ad000b0063b5f78d6dbmr5591751pfv.21.1683358337796; Sat, 06 May 2023 00:32:17 -0700 (PDT) Received: from localhost.localdomain ([120.138.12.87]) by smtp.gmail.com with ESMTPSA id z16-20020aa785d0000000b0062a56e51fd7sm2627373pfn.188.2023.05.06.00.32.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 06 May 2023 00:32:17 -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 8/8] PCI: qcom: Do not advertise hotplug capability for IP v2.1.0 Date: Sat, 6 May 2023 13:01:39 +0530 Message-Id: <20230506073139.8789-9-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 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" SoCs making use of Qcom PCIe controller IP v2.1.0 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 0x= 03c0 (issued 2020 msec ago) [ 5.810161] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x= 03c0 (issued 2048 msec ago) [ 7.838162] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x= 07c0 (issued 2020 msec ago) [ 7.870159] pcieport 0001:00:00.0: pciehp: Timeout on hotplug command 0x= 07c0 (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 | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controlle= r/dwc/pcie-qcom.c index 6fbaf7b419e6..68af95c836d2 100644 --- a/drivers/pci/controller/dwc/pcie-qcom.c +++ b/drivers/pci/controller/dwc/pcie-qcom.c @@ -373,6 +373,7 @@ static int qcom_pcie_post_init_2_1_0(struct qcom_pcie *= pcie) { struct qcom_pcie_resources_2_1_0 *res =3D &pcie->res.v2_1_0; struct dw_pcie *pci =3D pcie->pci; + u16 offset =3D dw_pcie_find_capability(pci, PCI_CAP_ID_EXP); struct device *dev =3D pci->dev; struct device_node *node =3D dev->of_node; u32 val; @@ -424,6 +425,14 @@ static int qcom_pcie_post_init_2_1_0(struct qcom_pcie = *pcie) writel(CFG_BRIDGE_SB_INIT, pci->dbi_base + AXI_MSTR_RESP_COMP_CTRL1); =20 + dw_pcie_dbi_ro_wr_en(pci); + + val =3D readl(pci->dbi_base + offset + PCI_EXP_SLTCAP); + val &=3D ~PCI_EXP_SLTCAP_HPC; + writel(val, pci->dbi_base + offset + PCI_EXP_SLTCAP); + + dw_pcie_dbi_ro_wr_dis(pci); + return 0; } =20 --=20 2.25.1