From nobody Wed Apr 8 14:47:55 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 3E91BECAAD5 for ; Sat, 10 Sep 2022 06:32:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230452AbiIJGb7 (ORCPT ); Sat, 10 Sep 2022 02:31:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230253AbiIJGbq (ORCPT ); Sat, 10 Sep 2022 02:31:46 -0400 Received: from mail-wr1-x435.google.com (mail-wr1-x435.google.com [IPv6:2a00:1450:4864:20::435]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 100126D9E0 for ; Fri, 9 Sep 2022 23:31:41 -0700 (PDT) Received: by mail-wr1-x435.google.com with SMTP id bj14so6532138wrb.12 for ; Fri, 09 Sep 2022 23:31:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date; bh=BmOWU26gjLBIOonkKcZ0ILBj0OeiqDzaVAugyvdHpNQ=; b=l8jZi7lseGJa72/OntBTkuPuDk/P0PB9iXvlzvIORfvCfD3bXM3yCQTFf6XSgv1PF5 uyMWu5P81vkQ9UYzOTchcdoXPUH/ztw2MMP5AuTylhJ7nfkxrZq3IRBybGeFyJuZu9dO idUP2QdUQgCCi5gO7MNy+n5crbG3CzVDVYhL2ZRLnzdQXaz0bn2LqshBCiZ5EmqqiEBt 0nO03a9wvb+74+eBY4Y85UJmUmEzs1MeLuw38Nslu3sxwuY4TmmvZKozlCndTt9buUuk AoUxjpMHh9bck/Srs8CPpu+/xcz9pdxiXZ9IxqgbHLHPbYTR/CmXlOtmPVgs8f4cZohU X+2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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; bh=BmOWU26gjLBIOonkKcZ0ILBj0OeiqDzaVAugyvdHpNQ=; b=6xW8ZxRr3kHuVUSdHmy4IylE/gtONzCbJvCzKjQk1yJtmtcDZulvr0D2jtBBvdIsbd QkBLM9M/vhQTMluds9VHJ6oU1XjttMcL3UjkcKjbDyEnjJ5rUwJVsA6d1w/Q6BS16tIw Vi2wdZ2UGOGLVnnI8ZWq1TVZyUui9zRRls3CEZNasaBbrHynxHhthL5vTe69vXdTtl98 ERjlk+CJAwQMwTDm1VPilyoquJoMOiriKYiZNfqTbJ8gXCend/4qXd6y1PId2eS709nc 6GXKZKJP1IxGDRlQfP2HxQPhaDlgI9BKBCZ9WC7isrOI8YwGupsMjTVjmzgJEnFji0ve qnGw== X-Gm-Message-State: ACgBeo23Q+It932p3bTyHezLRAseef0kNlU/jr3Kaz3C0hEh3exJpst5 +PO1J4Z638qcdwGXmHHYuWAs X-Google-Smtp-Source: AA6agR5ZancBBxmGlu6F9A9DnmcErtq69rlt5YyM7B+L6IQsVG0GzH5XSK9uI+ElK78X2QCbI0zevg== X-Received: by 2002:a5d:6484:0:b0:226:dd0e:b09c with SMTP id o4-20020a5d6484000000b00226dd0eb09cmr9899589wri.388.1662791501106; Fri, 09 Sep 2022 23:31:41 -0700 (PDT) Received: from localhost.localdomain ([117.217.182.47]) by smtp.gmail.com with ESMTPSA id n16-20020a05600c4f9000b003a5c7a942edsm2828122wmq.28.2022.09.09.23.31.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 09 Sep 2022 23:31:40 -0700 (PDT) From: Manivannan Sadhasivam To: lpieralisi@kernel.org, robh@kernel.org, andersson@kernel.org Cc: kw@linux.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, konrad.dybcio@somainline.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, devicetree@vger.kernel.org, dmitry.baryshkov@linaro.org, Manivannan Sadhasivam Subject: [PATCH v3 05/12] PCI: qcom-ep: Expose link transition counts via debugfs Date: Sat, 10 Sep 2022 12:00:38 +0530 Message-Id: <20220910063045.16648-6-manivannan.sadhasivam@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220910063045.16648-1-manivannan.sadhasivam@linaro.org> References: <20220910063045.16648-1-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" Qualcomm PCIe controllers have debug registers in the MMIO region that count PCIe link transitions. Expose them over debugfs to userspace to help debug the low power issues. Signed-off-by: Manivannan Sadhasivam --- drivers/pci/controller/dwc/pcie-qcom-ep.c | 60 +++++++++++++++++++++++ 1 file changed, 60 insertions(+) diff --git a/drivers/pci/controller/dwc/pcie-qcom-ep.c b/drivers/pci/contro= ller/dwc/pcie-qcom-ep.c index 72eb6cacdb3a..2dc6d4e44aff 100644 --- a/drivers/pci/controller/dwc/pcie-qcom-ep.c +++ b/drivers/pci/controller/dwc/pcie-qcom-ep.c @@ -10,6 +10,7 @@ */ =20 #include +#include #include #include #include @@ -45,6 +46,11 @@ #define PARF_ATU_BASE_ADDR 0x634 #define PARF_ATU_BASE_ADDR_HI 0x638 #define PARF_SRIS_MODE 0x644 +#define PARF_DEBUG_CNT_PM_LINKST_IN_L2 0xc04 +#define PARF_DEBUG_CNT_PM_LINKST_IN_L1 0xc0c +#define PARF_DEBUG_CNT_PM_LINKST_IN_L0S 0xc10 +#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1 0xc84 +#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2 0xc88 #define PARF_DEVICE_TYPE 0x1000 #define PARF_BDF_TO_SID_CFG 0x2c00 =20 @@ -135,12 +141,14 @@ enum qcom_pcie_ep_link_status { * @pci: Designware PCIe controller struct * @parf: Qualcomm PCIe specific PARF register base * @elbi: Designware PCIe specific ELBI register base + * @mmio: MMIO register base * @perst_map: PERST regmap * @mmio_res: MMIO region resource * @core_reset: PCIe Endpoint core reset * @reset: PERST# GPIO * @wake: WAKE# GPIO * @phy: PHY controller block + * @debugfs: PCIe Endpoint Debugfs directory * @clks: PCIe clocks * @num_clks: PCIe clocks count * @perst_en: Flag for PERST enable @@ -154,6 +162,7 @@ struct qcom_pcie_ep { =20 void __iomem *parf; void __iomem *elbi; + void __iomem *mmio; struct regmap *perst_map; struct resource *mmio_res; =20 @@ -161,6 +170,7 @@ struct qcom_pcie_ep { struct gpio_desc *reset; struct gpio_desc *wake; struct phy *phy; + struct dentry *debugfs; =20 struct clk_bulk_data *clks; int num_clks; @@ -446,6 +456,9 @@ static int qcom_pcie_ep_get_io_resources(struct platfor= m_device *pdev, =20 pcie_ep->mmio_res =3D platform_get_resource_byname(pdev, IORESOURCE_MEM, "mmio"); + pcie_ep->mmio =3D devm_pci_remap_cfg_resource(dev, pcie_ep->mmio_res); + if (IS_ERR(pcie_ep->mmio)) + return PTR_ERR(pcie_ep->mmio); =20 syscon =3D of_parse_phandle(dev->of_node, "qcom,perst-regs", 0); if (!syscon) { @@ -629,6 +642,37 @@ static int qcom_pcie_ep_raise_irq(struct dw_pcie_ep *e= p, u8 func_no, } } =20 +static int qcom_pcie_ep_link_transition_count(struct seq_file *s, void *da= ta) +{ + struct qcom_pcie_ep *pcie_ep =3D (struct qcom_pcie_ep *) + dev_get_drvdata(s->private); + + seq_printf(s, "L0s transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L0S)); + + seq_printf(s, "L1 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L1)); + + seq_printf(s, "L1.1 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1)); + + seq_printf(s, "L1.2 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2)); + + seq_printf(s, "L2 transition count: %u\n", + readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L2)); + + return 0; +} + +static void qcom_pcie_ep_init_debugfs(struct qcom_pcie_ep *pcie_ep) +{ + struct dw_pcie *pci =3D &pcie_ep->pci; + + debugfs_create_devm_seqfile(pci->dev, "link_transition_count", pcie_ep->d= ebugfs, + qcom_pcie_ep_link_transition_count); +} + static const struct pci_epc_features qcom_pcie_epc_features =3D { .linkup_notifier =3D true, .core_init_notifier =3D true, @@ -661,6 +705,7 @@ static int qcom_pcie_ep_probe(struct platform_device *p= dev) { struct device *dev =3D &pdev->dev; struct qcom_pcie_ep *pcie_ep; + char *name; int ret; =20 pcie_ep =3D devm_kzalloc(dev, sizeof(*pcie_ep), GFP_KERNEL); @@ -686,8 +731,21 @@ static int qcom_pcie_ep_probe(struct platform_device *= pdev) if (ret) goto err_disable_resources; =20 + name =3D devm_kasprintf(dev, GFP_KERNEL, "%pOFP", dev->of_node); + if (!name) { + ret =3D -ENOMEM; + goto err_disable_irqs; + } + + pcie_ep->debugfs =3D debugfs_create_dir(name, NULL); + qcom_pcie_ep_init_debugfs(pcie_ep); + return 0; =20 +err_disable_irqs: + disable_irq(pcie_ep->global_irq); + disable_irq(pcie_ep->perst_irq); + err_disable_resources: qcom_pcie_disable_resources(pcie_ep); =20 @@ -701,6 +759,8 @@ static int qcom_pcie_ep_remove(struct platform_device *= pdev) disable_irq(pcie_ep->global_irq); disable_irq(pcie_ep->perst_irq); =20 + debugfs_remove_recursive(pcie_ep->debugfs); + if (pcie_ep->link_status =3D=3D QCOM_PCIE_EP_LINK_DISABLED) return 0; =20 --=20 2.25.1