From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx07-00178001.pphosted.com (mx07-00178001.pphosted.com [185.132.182.106]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7FA012D9795; Wed, 20 Aug 2025 07:59:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.132.182.106 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755676796; cv=none; b=TKVFe7xhYcPo8mzpzqZ0/qgwkmhwtQj4zmJbtXVchDPBJYOz7hZh1NgFduXVltsQHQl9OFSuNfJqMAtUgfr04DHO78a3uFy5Qq+XKADZ6tW8j05dK82pPqU5L4ZDuCsg03ERU3+if30n91htIr2WdaMiZd96V7HybB5K2NzGIPY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755676796; c=relaxed/simple; bh=E5OAxrCJtfqf/kJ4fq1ndAu8X5DfgdiE13ErNTuQ9Wo=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=q+vQCPveIleQP+g8S2GJJR7LRcIyY/e6dJsUbE/ZRoSrjHL45WOhEcmxZv7+sr6wIOGpZh0WZSZIIX2tcTs2oV5iuEhDnF6QKn6innjijf+1eTdgb8RwN0mUwKxTLQ5sYADI3hCMfvGXEIUmiKpA5s6kwUiQJZsxDzmjciouJZY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com; spf=pass smtp.mailfrom=foss.st.com; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b=5Zle2nhA; arc=none smtp.client-ip=185.132.182.106 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=foss.st.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=foss.st.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=foss.st.com header.i=@foss.st.com header.b="5Zle2nhA" Received: from pps.filterd (m0288072.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 57K7mDOm000448; Wed, 20 Aug 2025 09:59:26 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=selector1; bh= V7pDN2QsWi68h0Pgw4S/otGNcYYQUoSlPYlDoWrqANw=; b=5Zle2nhAqY8EV3uu dYw4wJaSVpmLoXLtusObC6iQF6g6K/QSW1iPxV0IwUO6A6L/y95W0led81yoL+oP 1i3KKqMdk3FPmbT1IuqYhXXBYuY2jcFWenlk2ZiLN9lXU5pcwnGBtwqOafltNQGS YmKkMyrpRqsrpM+338O1GIXfLE/Fmsv/2R0YTiqm7Hy8nkI1f5wF0KkZQNOCL4DN 4e3vAn20Pcgav5JT5F6cKbNO0OaHSCXR3zlyX9bVbUMvLA/Kgz0VrsP22s3qEwcR Pb+mI29EgD0oWYnSjZQzXp7pw4knT7d1tKFoFI+zLbTDUSfg6mgOmeKaQqtTP642 s+s2Fw== Received: from beta.dmz-ap.st.com (beta.dmz-ap.st.com [138.198.100.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 48n7548x92-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 20 Aug 2025 09:59:26 +0200 (MEST) Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-ap.st.com (STMicroelectronics) with ESMTP id A0F5D40044; Wed, 20 Aug 2025 09:57:31 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node3.st.com [10.75.129.71]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 8D7275E811F; Wed, 20 Aug 2025 09:56:08 +0200 (CEST) Received: from localhost (10.130.77.120) by SHFDAG1NODE3.st.com (10.75.129.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.39; Wed, 20 Aug 2025 09:56:08 +0200 From: Christian Bruel To: , , , , , , , , , , , , , , , , , , , CC: , , , , , , , Subject: [PATCH v13 06/11] PCI: stm32: Add PCIe Endpoint support for STM32MP25 Date: Wed, 20 Aug 2025 09:54:06 +0200 Message-ID: <20250820075411.1178729-7-christian.bruel@foss.st.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250820075411.1178729-1-christian.bruel@foss.st.com> References: <20250820075411.1178729-1-christian.bruel@foss.st.com> Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: SHFCAS1NODE1.st.com (10.75.129.72) To SHFDAG1NODE3.st.com (10.75.129.71) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-08-20_03,2025-08-20_01,2025-03-28_01 Add driver to configure the STM32MP25 SoC PCIe Gen1 2.5GT/s or Gen2 5GT/s controller based on the DesignWare PCIe core in endpoint mode. Uses the common reference clock provided by the host. The PCIe core_clk receives the pipe0_clk from the ComboPHY as input, and the ComboPHY PLL must be locked for pipe0_clk to be ready. Consequently, PCIe core registers cannot be accessed until the ComboPHY is fully initialised and REFCLK is enabled and ready. Signed-off-by: Christian Bruel --- drivers/pci/controller/dwc/Kconfig | 12 + drivers/pci/controller/dwc/Makefile | 1 + drivers/pci/controller/dwc/pcie-stm32-ep.c | 384 +++++++++++++++++++++ drivers/pci/controller/dwc/pcie-stm32.h | 1 + 4 files changed, 398 insertions(+) create mode 100644 drivers/pci/controller/dwc/pcie-stm32-ep.c diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig index a8174817fd5b..34abc859c107 100644 --- a/drivers/pci/controller/dwc/Kconfig +++ b/drivers/pci/controller/dwc/Kconfig @@ -435,6 +435,18 @@ config PCIE_STM32_HOST This driver can also be built as a module. If so, the module will be called pcie-stm32. +config PCIE_STM32_EP + tristate "STMicroelectronics STM32MP25 PCIe Controller (endpoint mode)" + depends on ARCH_STM32 || COMPILE_TEST + depends on PCI_ENDPOINT + select PCIE_DW_EP + help + Enables Endpoint (EP) support for the DesignWare core based PCIe + controller found in STM32MP25 SoC. + + This driver can also be built as a module. If so, the module + will be called pcie-stm32-ep. + config PCI_DRA7XX tristate diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile index 1307a87b1cf0..7ae28f3b0fb3 100644 --- a/drivers/pci/controller/dwc/Makefile +++ b/drivers/pci/controller/dwc/Makefile @@ -32,6 +32,7 @@ obj-$(CONFIG_PCIE_UNIPHIER_EP) += pcie-uniphier-ep.o obj-$(CONFIG_PCIE_VISCONTI_HOST) += pcie-visconti.o obj-$(CONFIG_PCIE_RCAR_GEN4) += pcie-rcar-gen4.o obj-$(CONFIG_PCIE_STM32_HOST) += pcie-stm32.o +obj-$(CONFIG_PCIE_STM32_EP) += pcie-stm32-ep.o # The following drivers are for devices that use the generic ACPI # pci_root.c driver but don't support standard ECAM config access. diff --git a/drivers/pci/controller/dwc/pcie-stm32-ep.c b/drivers/pci/controller/dwc/pcie-stm32-ep.c new file mode 100644 index 000000000000..1f46bcf0c79f --- /dev/null +++ b/drivers/pci/controller/dwc/pcie-stm32-ep.c @@ -0,0 +1,384 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * STMicroelectronics STM32MP25 PCIe endpoint driver. + * + * Copyright (C) 2025 STMicroelectronics + * Author: Christian Bruel + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "pcie-designware.h" +#include "pcie-stm32.h" + +enum stm32_pcie_ep_link_status { + STM32_PCIE_EP_LINK_DISABLED, + STM32_PCIE_EP_LINK_ENABLED, +}; + +struct stm32_pcie { + struct dw_pcie pci; + struct regmap *regmap; + struct reset_control *rst; + struct phy *phy; + struct clk *clk; + struct gpio_desc *perst_gpio; + enum stm32_pcie_ep_link_status link_status; + unsigned int perst_irq; +}; + +static void stm32_pcie_ep_init(struct dw_pcie_ep *ep) +{ + struct dw_pcie *pci = to_dw_pcie_from_ep(ep); + enum pci_barno bar; + + for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) + dw_pcie_ep_reset_bar(pci, bar); +} + +static int stm32_pcie_enable_link(struct dw_pcie *pci) +{ + struct stm32_pcie *stm32_pcie = to_stm32_pcie(pci); + + regmap_update_bits(stm32_pcie->regmap, SYSCFG_PCIECR, + STM32MP25_PCIECR_LTSSM_EN, + STM32MP25_PCIECR_LTSSM_EN); + + return dw_pcie_wait_for_link(pci); +} + +static void stm32_pcie_disable_link(struct dw_pcie *pci) +{ + struct stm32_pcie *stm32_pcie = to_stm32_pcie(pci); + + regmap_update_bits(stm32_pcie->regmap, SYSCFG_PCIECR, STM32MP25_PCIECR_LTSSM_EN, 0); +} + +static int stm32_pcie_start_link(struct dw_pcie *pci) +{ + struct stm32_pcie *stm32_pcie = to_stm32_pcie(pci); + int ret; + + if (stm32_pcie->link_status == STM32_PCIE_EP_LINK_ENABLED) { + dev_dbg(pci->dev, "Link is already enabled\n"); + return 0; + } + + dev_dbg(pci->dev, "Enable link\n"); + + ret = stm32_pcie_enable_link(pci); + if (ret) { + dev_err(pci->dev, "PCIe cannot establish link: %d\n", ret); + return ret; + } + + enable_irq(stm32_pcie->perst_irq); + + stm32_pcie->link_status = STM32_PCIE_EP_LINK_ENABLED; + + return 0; +} + +static void stm32_pcie_stop_link(struct dw_pcie *pci) +{ + struct stm32_pcie *stm32_pcie = to_stm32_pcie(pci); + + if (stm32_pcie->link_status == STM32_PCIE_EP_LINK_DISABLED) { + dev_dbg(pci->dev, "Link is already disabled\n"); + return; + } + + dev_dbg(pci->dev, "Disable link\n"); + + disable_irq(stm32_pcie->perst_irq); + + stm32_pcie_disable_link(pci); + + stm32_pcie->link_status = STM32_PCIE_EP_LINK_DISABLED; +} + +static int stm32_pcie_raise_irq(struct dw_pcie_ep *ep, u8 func_no, + unsigned int type, u16 interrupt_num) +{ + struct dw_pcie *pci = to_dw_pcie_from_ep(ep); + + switch (type) { + case PCI_IRQ_INTX: + return dw_pcie_ep_raise_intx_irq(ep, func_no); + case PCI_IRQ_MSI: + return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num); + default: + dev_err(pci->dev, "UNKNOWN IRQ type\n"); + return -EINVAL; + } +} + +static const struct pci_epc_features stm32_pcie_epc_features = { + .msi_capable = true, + .align = SZ_64K, +}; + +static const struct pci_epc_features* +stm32_pcie_get_features(struct dw_pcie_ep *ep) +{ + return &stm32_pcie_epc_features; +} + +static const struct dw_pcie_ep_ops stm32_pcie_ep_ops = { + .init = stm32_pcie_ep_init, + .raise_irq = stm32_pcie_raise_irq, + .get_features = stm32_pcie_get_features, +}; + +static const struct dw_pcie_ops dw_pcie_ops = { + .start_link = stm32_pcie_start_link, + .stop_link = stm32_pcie_stop_link, +}; + +static int stm32_pcie_enable_resources(struct stm32_pcie *stm32_pcie) +{ + int ret; + + ret = phy_init(stm32_pcie->phy); + if (ret) + return ret; + + ret = clk_prepare_enable(stm32_pcie->clk); + if (ret) + phy_exit(stm32_pcie->phy); + + return ret; +} + +static void stm32_pcie_disable_resources(struct stm32_pcie *stm32_pcie) +{ + clk_disable_unprepare(stm32_pcie->clk); + + phy_exit(stm32_pcie->phy); +} + +static void stm32_pcie_perst_assert(struct dw_pcie *pci) +{ + struct stm32_pcie *stm32_pcie = to_stm32_pcie(pci); + struct dw_pcie_ep *ep = &stm32_pcie->pci.ep; + struct device *dev = pci->dev; + + dev_dbg(dev, "PERST asserted by host\n"); + + pci_epc_deinit_notify(ep->epc); + + stm32_pcie_disable_resources(stm32_pcie); + + pm_runtime_put_sync(dev); +} + +static void stm32_pcie_perst_deassert(struct dw_pcie *pci) +{ + struct stm32_pcie *stm32_pcie = to_stm32_pcie(pci); + struct device *dev = pci->dev; + struct dw_pcie_ep *ep = &pci->ep; + int ret; + + dev_dbg(dev, "PERST de-asserted by host\n"); + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) { + dev_err(dev, "Failed to resume runtime PM: %d\n", ret); + return; + } + + ret = stm32_pcie_enable_resources(stm32_pcie); + if (ret) { + dev_err(dev, "Failed to enable resources: %d\n", ret); + goto err_pm_put_sync; + } + + /* + * Need to reprogram the configuration space registers here because the + * DBI registers were incorrectly reset by the PHY RCC during phy_init(). + */ + ret = dw_pcie_ep_init_registers(ep); + if (ret) { + dev_err(dev, "Failed to complete initialization: %d\n", ret); + goto err_disable_resources; + } + + pci_epc_init_notify(ep->epc); + + return; + +err_disable_resources: + stm32_pcie_disable_resources(stm32_pcie); + +err_pm_put_sync: + pm_runtime_put_sync(dev); +} + +static irqreturn_t stm32_pcie_ep_perst_irq_thread(int irq, void *data) +{ + struct stm32_pcie *stm32_pcie = data; + struct dw_pcie *pci = &stm32_pcie->pci; + u32 perst; + + perst = gpiod_get_value(stm32_pcie->perst_gpio); + if (perst) + stm32_pcie_perst_assert(pci); + else + stm32_pcie_perst_deassert(pci); + + irq_set_irq_type(gpiod_to_irq(stm32_pcie->perst_gpio), + (perst ? IRQF_TRIGGER_HIGH : IRQF_TRIGGER_LOW)); + + return IRQ_HANDLED; +} + +static int stm32_add_pcie_ep(struct stm32_pcie *stm32_pcie, + struct platform_device *pdev) +{ + struct dw_pcie_ep *ep = &stm32_pcie->pci.ep; + struct device *dev = &pdev->dev; + int ret; + + ret = regmap_update_bits(stm32_pcie->regmap, SYSCFG_PCIECR, + STM32MP25_PCIECR_TYPE_MASK, + STM32MP25_PCIECR_EP); + if (ret) + return ret; + + reset_control_assert(stm32_pcie->rst); + reset_control_deassert(stm32_pcie->rst); + + ep->ops = &stm32_pcie_ep_ops; + + ret = dw_pcie_ep_init(ep); + if (ret) { + dev_err(dev, "Failed to initialize ep: %d\n", ret); + return ret; + } + + ret = stm32_pcie_enable_resources(stm32_pcie); + if (ret) { + dev_err(dev, "Failed to enable resources: %d\n", ret); + dw_pcie_ep_deinit(ep); + return ret; + } + + return 0; +} + +static int stm32_pcie_probe(struct platform_device *pdev) +{ + struct stm32_pcie *stm32_pcie; + struct device *dev = &pdev->dev; + int ret; + + stm32_pcie = devm_kzalloc(dev, sizeof(*stm32_pcie), GFP_KERNEL); + if (!stm32_pcie) + return -ENOMEM; + + stm32_pcie->pci.dev = dev; + stm32_pcie->pci.ops = &dw_pcie_ops; + + stm32_pcie->regmap = syscon_regmap_lookup_by_compatible("st,stm32mp25-syscfg"); + if (IS_ERR(stm32_pcie->regmap)) + return dev_err_probe(dev, PTR_ERR(stm32_pcie->regmap), + "No syscfg specified\n"); + + stm32_pcie->phy = devm_phy_get(dev, NULL); + if (IS_ERR(stm32_pcie->phy)) + return dev_err_probe(dev, PTR_ERR(stm32_pcie->phy), + "failed to get pcie-phy\n"); + + stm32_pcie->clk = devm_clk_get(dev, NULL); + if (IS_ERR(stm32_pcie->clk)) + return dev_err_probe(dev, PTR_ERR(stm32_pcie->clk), + "Failed to get PCIe clock source\n"); + + stm32_pcie->rst = devm_reset_control_get_exclusive(dev, NULL); + if (IS_ERR(stm32_pcie->rst)) + return dev_err_probe(dev, PTR_ERR(stm32_pcie->rst), + "Failed to get PCIe reset\n"); + + stm32_pcie->perst_gpio = devm_gpiod_get(dev, "reset", GPIOD_IN); + if (IS_ERR(stm32_pcie->perst_gpio)) + return dev_err_probe(dev, PTR_ERR(stm32_pcie->perst_gpio), + "Failed to get reset GPIO\n"); + + ret = phy_set_mode(stm32_pcie->phy, PHY_MODE_PCIE); + if (ret) + return ret; + + platform_set_drvdata(pdev, stm32_pcie); + + pm_runtime_get_noresume(dev); + + ret = devm_pm_runtime_enable(dev); + if (ret < 0) { + pm_runtime_put_noidle(&pdev->dev); + return dev_err_probe(dev, ret, "Failed to enable runtime PM\n"); + } + + stm32_pcie->perst_irq = gpiod_to_irq(stm32_pcie->perst_gpio); + + /* Will be enabled in start_link when device is initialized. */ + irq_set_status_flags(stm32_pcie->perst_irq, IRQ_NOAUTOEN); + + ret = devm_request_threaded_irq(dev, stm32_pcie->perst_irq, NULL, + stm32_pcie_ep_perst_irq_thread, + IRQF_TRIGGER_HIGH | IRQF_ONESHOT, + "perst_irq", stm32_pcie); + if (ret) { + pm_runtime_put_noidle(&pdev->dev); + return dev_err_probe(dev, ret, "Failed to request PERST IRQ\n"); + } + + ret = stm32_add_pcie_ep(stm32_pcie, pdev); + if (ret) + pm_runtime_put_noidle(&pdev->dev); + + return ret; +} + +static void stm32_pcie_remove(struct platform_device *pdev) +{ + struct stm32_pcie *stm32_pcie = platform_get_drvdata(pdev); + struct dw_pcie *pci = &stm32_pcie->pci; + struct dw_pcie_ep *ep = &pci->ep; + + dw_pcie_stop_link(pci); + + pci_epc_deinit_notify(ep->epc); + dw_pcie_ep_deinit(ep); + + stm32_pcie_disable_resources(stm32_pcie); + + pm_runtime_put_sync(&pdev->dev); +} + +static const struct of_device_id stm32_pcie_ep_of_match[] = { + { .compatible = "st,stm32mp25-pcie-ep" }, + {}, +}; + +static struct platform_driver stm32_pcie_ep_driver = { + .probe = stm32_pcie_probe, + .remove = stm32_pcie_remove, + .driver = { + .name = "stm32-ep-pcie", + .of_match_table = stm32_pcie_ep_of_match, + }, +}; + +module_platform_driver(stm32_pcie_ep_driver); + +MODULE_AUTHOR("Christian Bruel "); +MODULE_DESCRIPTION("STM32MP25 PCIe Endpoint Controller driver"); +MODULE_LICENSE("GPL"); +MODULE_DEVICE_TABLE(of, stm32_pcie_ep_of_match); diff --git a/drivers/pci/controller/dwc/pcie-stm32.h b/drivers/pci/controller/dwc/pcie-stm32.h index 387112c4e42c..09d39f04e469 100644 --- a/drivers/pci/controller/dwc/pcie-stm32.h +++ b/drivers/pci/controller/dwc/pcie-stm32.h @@ -9,6 +9,7 @@ #define to_stm32_pcie(x) dev_get_drvdata((x)->dev) #define STM32MP25_PCIECR_TYPE_MASK GENMASK(11, 8) +#define STM32MP25_PCIECR_EP 0 #define STM32MP25_PCIECR_LTSSM_EN BIT(2) #define STM32MP25_PCIECR_RC BIT(10) -- 2.34.1