Re: [PATCH v13 04/11] PCI: stm32: Add PCIe host support for STM32MP25

[Philipp Zabel <p.zabel@pengutronix.de>]

On Mi, 2025-08-20 at 09:54 +0200, Christian Bruel wrote:
> Add driver for the STM32MP25 SoC PCIe Gen1 2.5 GT/s and Gen2 5GT/s
> controller based on the DesignWare PCIe core.
> 
> Supports MSI via GICv2m, Single Virtual Channel, Single Function
> 
> Supports WAKE# GPIO.
> 
> Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
> ---
>  drivers/pci/controller/dwc/Kconfig      |  12 +
>  drivers/pci/controller/dwc/Makefile     |   1 +
>  drivers/pci/controller/dwc/pcie-stm32.c | 360 ++++++++++++++++++++++++
>  drivers/pci/controller/dwc/pcie-stm32.h |  15 +
>  4 files changed, 388 insertions(+)
>  create mode 100644 drivers/pci/controller/dwc/pcie-stm32.c
>  create mode 100644 drivers/pci/controller/dwc/pcie-stm32.h
> 
> diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
> index deafc512b079..a8174817fd5b 100644
> --- a/drivers/pci/controller/dwc/Kconfig
> +++ b/drivers/pci/controller/dwc/Kconfig
> @@ -423,6 +423,18 @@ config PCIE_SPEAR13XX
>  	help
>  	  Say Y here if you want PCIe support on SPEAr13XX SoCs.
>  
> +config PCIE_STM32_HOST
> +	tristate "STMicroelectronics STM32MP25 PCIe Controller (host mode)"
> +	depends on ARCH_STM32 || COMPILE_TEST
> +	depends on PCI_MSI
> +	select PCIE_DW_HOST
> +	help
> +	  Enables Root Complex (RC) 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.
> +
>  config PCI_DRA7XX
>  	tristate
>  
> diff --git a/drivers/pci/controller/dwc/Makefile b/drivers/pci/controller/dwc/Makefile
> index 6919d27798d1..1307a87b1cf0 100644
> --- a/drivers/pci/controller/dwc/Makefile
> +++ b/drivers/pci/controller/dwc/Makefile
> @@ -31,6 +31,7 @@ obj-$(CONFIG_PCIE_UNIPHIER) += pcie-uniphier.o
>  obj-$(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
>  
>  # 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.c b/drivers/pci/controller/dwc/pcie-stm32.c
> new file mode 100644
> index 000000000000..964fa6f674c8
> --- /dev/null
> +++ b/drivers/pci/controller/dwc/pcie-stm32.c
> @@ -0,0 +1,360 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * STMicroelectronics STM32MP25 PCIe root complex driver.
> + *
> + * Copyright (C) 2025 STMicroelectronics
> + * Author: Christian Bruel <christian.bruel@foss.st.com>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/of_platform.h>
> +#include <linux/phy/phy.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/pm_wakeirq.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include "pcie-designware.h"
> +#include "pcie-stm32.h"
> +#include "../../pci.h"
> +
> +struct stm32_pcie {
> +	struct dw_pcie pci;
> +	struct regmap *regmap;
> +	struct reset_control *rst;

This could be a local variable in stm32_pcie_probe().

regards
Philipp