Re: [PATCH v6 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver
From: Rob Herring
Date: Wed Apr 29 2020 - 15:14:58 EST
On Fri, Apr 24, 2020 at 05:34:04PM +0530, Bharat Kumar Gogada wrote:
> - Add support for Versal CPM as Root Port.
> - The Versal ACAP devices include CCIX-PCIe Module (CPM). The integrated
> block for CPM along with the integrated bridge can function
> as PCIe Root Port.
> - Bridge error and legacy interrupts in Versal CPM are handled using
> Versal CPM specific MISC interrupt line.
>
> Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxxxxx>
> ---
> drivers/pci/controller/Kconfig | 9 +
> drivers/pci/controller/Makefile | 1 +
> drivers/pci/controller/pcie-xilinx-cpm.c | 521 +++++++++++++++++++++++++++++++
> 3 files changed, 531 insertions(+)
> create mode 100644 drivers/pci/controller/pcie-xilinx-cpm.c
>
> diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
> index 20bf00f..ca0ae24 100644
> --- a/drivers/pci/controller/Kconfig
> +++ b/drivers/pci/controller/Kconfig
> @@ -81,6 +81,15 @@ config PCIE_XILINX
> Say 'Y' here if you want kernel to support the Xilinx AXI PCIe
> Host Bridge driver.
>
> +config PCIE_XILINX_CPM
> + bool "Xilinx Versal CPM host bridge support"
Why can't this be a module?
> + depends on ARCH_ZYNQMP || COMPILE_TEST
> + select PCI_HOST_COMMON
> + help
> + Say 'Y' here if you want kernel support for the
> + Xilinx Versal CPM host bridge. The driver supports
> + MSI/MSI-X interrupts using GICv3 ITS feature.
> +
> config PCI_XGENE
> bool "X-Gene PCIe controller"
> depends on ARM64 || COMPILE_TEST
> diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
> index 01b2502..78dabda 100644
> --- a/drivers/pci/controller/Makefile
> +++ b/drivers/pci/controller/Makefile
> @@ -12,6 +12,7 @@ obj-$(CONFIG_PCI_HOST_COMMON) += pci-host-common.o
> obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
> obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
> obj-$(CONFIG_PCIE_XILINX_NWL) += pcie-xilinx-nwl.o
> +obj-$(CONFIG_PCIE_XILINX_CPM) += pcie-xilinx-cpm.o
> obj-$(CONFIG_PCI_V3_SEMI) += pci-v3-semi.o
> obj-$(CONFIG_PCI_XGENE_MSI) += pci-xgene-msi.o
> obj-$(CONFIG_PCI_VERSATILE) += pci-versatile.o
> diff --git a/drivers/pci/controller/pcie-xilinx-cpm.c b/drivers/pci/controller/pcie-xilinx-cpm.c
> new file mode 100644
> index 0000000..30ddec5
> --- /dev/null
> +++ b/drivers/pci/controller/pcie-xilinx-cpm.c
> @@ -0,0 +1,521 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * PCIe host controller driver for Xilinx Versal CPM DMA Bridge
> + *
> + * (C) Copyright 2019 - 2020, Xilinx, Inc.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_pci.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_irq.h>
> +#include <linux/pci.h>
> +#include <linux/platform_device.h>
> +#include <linux/pci-ecam.h>
> +
> +#include "../pci.h"
> +
> +/* Register definitions */
> +#define XILINX_CPM_PCIE_REG_IDR 0x00000E10
> +#define XILINX_CPM_PCIE_REG_IMR 0x00000E14
> +#define XILINX_CPM_PCIE_REG_PSCR 0x00000E1C
> +#define XILINX_CPM_PCIE_REG_RPSC 0x00000E20
> +#define XILINX_CPM_PCIE_REG_RPEFR 0x00000E2C
> +#define XILINX_CPM_PCIE_REG_IDRN 0x00000E38
> +#define XILINX_CPM_PCIE_REG_IDRN_MASK 0x00000E3C
> +#define XILINX_CPM_PCIE_MISC_IR_STATUS 0x00000340
> +#define XILINX_CPM_PCIE_MISC_IR_ENABLE 0x00000348
> +#define XILINX_CPM_PCIE_MISC_IR_LOCAL BIT(1)
> +
> +/* Interrupt registers definitions */
> +#define XILINX_CPM_PCIE_INTR_LINK_DOWN BIT(0)
> +#define XILINX_CPM_PCIE_INTR_HOT_RESET BIT(3)
> +#define XILINX_CPM_PCIE_INTR_CFG_TIMEOUT BIT(8)
> +#define XILINX_CPM_PCIE_INTR_CORRECTABLE BIT(9)
> +#define XILINX_CPM_PCIE_INTR_NONFATAL BIT(10)
> +#define XILINX_CPM_PCIE_INTR_FATAL BIT(11)
> +#define XILINX_CPM_PCIE_INTR_INTX BIT(16)
> +#define XILINX_CPM_PCIE_INTR_MSI BIT(17)
> +#define XILINX_CPM_PCIE_INTR_SLV_UNSUPP BIT(20)
> +#define XILINX_CPM_PCIE_INTR_SLV_UNEXP BIT(21)
> +#define XILINX_CPM_PCIE_INTR_SLV_COMPL BIT(22)
> +#define XILINX_CPM_PCIE_INTR_SLV_ERRP BIT(23)
> +#define XILINX_CPM_PCIE_INTR_SLV_CMPABT BIT(24)
> +#define XILINX_CPM_PCIE_INTR_SLV_ILLBUR BIT(25)
> +#define XILINX_CPM_PCIE_INTR_MST_DECERR BIT(26)
> +#define XILINX_CPM_PCIE_INTR_MST_SLVERR BIT(27)
> +#define XILINX_CPM_PCIE_IMR_ALL_MASK 0x1FF39FF9
> +#define XILINX_CPM_PCIE_IDR_ALL_MASK 0xFFFFFFFF
> +#define XILINX_CPM_PCIE_IDRN_MASK GENMASK(19, 16)
> +#define XILINX_CPM_PCIE_INTR_CFG_PCIE_TIMEOUT BIT(4)
> +#define XILINX_CPM_PCIE_INTR_CFG_ERR_POISON BIT(12)
> +#define XILINX_CPM_PCIE_INTR_PME_TO_ACK_RCVD BIT(15)
> +#define XILINX_CPM_PCIE_INTR_PM_PME_RCVD BIT(17)
> +#define XILINX_CPM_PCIE_INTR_SLV_PCIE_TIMEOUT BIT(28)
> +#define XILINX_CPM_PCIE_IDRN_SHIFT 16
> +
> +/* Root Port Error FIFO Read Register definitions */
> +#define XILINX_CPM_PCIE_RPEFR_ERR_VALID BIT(18)
> +#define XILINX_CPM_PCIE_RPEFR_REQ_ID GENMASK(15, 0)
> +#define XILINX_CPM_PCIE_RPEFR_ALL_MASK 0xFFFFFFFF
> +
> +/* Root Port Status/control Register definitions */
> +#define XILINX_CPM_PCIE_REG_RPSC_BEN BIT(0)
> +
> +/* Phy Status/Control Register definitions */
> +#define XILINX_CPM_PCIE_REG_PSCR_LNKUP BIT(11)
> +
> +/**
> + * struct xilinx_cpm_pcie_port - PCIe port information
> + * @reg_base: Bridge Register Base
> + * @cpm_base: CPM System Level Control and Status Register(SLCR) Base
> + * @irq: Interrupt number
> + * @root_busno: Root Bus number
> + * @dev: Device pointer
> + * @leg_domain: Legacy IRQ domain pointer
> + * @irq_misc: Legacy and error interrupt number
> + * @leg_mask_lock: lock for legacy interrupts
> + */
> +struct xilinx_cpm_pcie_port {
> + void __iomem *reg_base;
> + void __iomem *cpm_base;
> + u32 irq;
Unused?
> + u8 root_busno;
Shouldn't need this. The bus number gets stored in the bridge struct.
> + struct device *dev;
> + struct irq_domain *leg_domain;
> + struct pci_config_window *cfg;
> + int irq_misc;
> + raw_spinlock_t leg_mask_lock;
> +};
> +
> +static inline u32 pcie_read(struct xilinx_cpm_pcie_port *port, u32 reg)
> +{
> + return readl(port->reg_base + reg);
> +}
> +
> +static inline void pcie_write(struct xilinx_cpm_pcie_port *port,
> + u32 val, u32 reg)
> +{
> + writel(val, port->reg_base + reg);
> +}
> +
> +static inline bool cpm_pcie_link_up(struct xilinx_cpm_pcie_port *port)
> +{
> + return (pcie_read(port, XILINX_CPM_PCIE_REG_PSCR) &
> + XILINX_CPM_PCIE_REG_PSCR_LNKUP) ? 1 : 0;
> +}
> +
> +/**
> + * xilinx_cpm_pcie_clear_err_interrupts - Clear Error Interrupts
> + * @port: PCIe port information
> + */
> +static void cpm_pcie_clear_err_interrupts(struct xilinx_cpm_pcie_port *port)
> +{
> + unsigned long val = pcie_read(port, XILINX_CPM_PCIE_REG_RPEFR);
> +
> + if (val & XILINX_CPM_PCIE_RPEFR_ERR_VALID) {
> + dev_dbg(port->dev, "Requester ID %lu\n",
> + val & XILINX_CPM_PCIE_RPEFR_REQ_ID);
> + pcie_write(port, XILINX_CPM_PCIE_RPEFR_ALL_MASK,
> + XILINX_CPM_PCIE_REG_RPEFR);
> + }
> +}
> +
> +static void xilinx_cpm_mask_leg_irq(struct irq_data *data)
> +{
> + struct irq_desc *desc = irq_to_desc(data->irq);
> + struct xilinx_cpm_pcie_port *port;
> + unsigned long flags;
> + u32 mask;
> + u32 val;
> +
> + port = irq_desc_get_chip_data(desc);
> + mask = (1 << data->hwirq) << XILINX_CPM_PCIE_IDRN_SHIFT;
> + raw_spin_lock_irqsave(&port->leg_mask_lock, flags);
> + val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN_MASK);
> + pcie_write(port, (val & (~mask)), XILINX_CPM_PCIE_REG_IDRN_MASK);
> + raw_spin_unlock_irqrestore(&port->leg_mask_lock, flags);
> +}
> +
> +static void xilinx_cpm_unmask_leg_irq(struct irq_data *data)
> +{
> + struct irq_desc *desc = irq_to_desc(data->irq);
> + struct xilinx_cpm_pcie_port *port;
> + unsigned long flags;
> + u32 mask;
> + u32 val;
> +
> + port = irq_desc_get_chip_data(desc);
> + mask = (1 << data->hwirq) << XILINX_CPM_PCIE_IDRN_SHIFT;
> + raw_spin_lock_irqsave(&port->leg_mask_lock, flags);
> + val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN_MASK);
> + pcie_write(port, (val | mask), XILINX_CPM_PCIE_REG_IDRN_MASK);
> + raw_spin_unlock_irqrestore(&port->leg_mask_lock, flags);
> +}
> +
> +static struct irq_chip xilinx_cpm_leg_irq_chip = {
> + .name = "xilinx_cpm_pcie:legacy",
> + .irq_enable = xilinx_cpm_unmask_leg_irq,
> + .irq_disable = xilinx_cpm_mask_leg_irq,
> + .irq_mask = xilinx_cpm_mask_leg_irq,
> + .irq_unmask = xilinx_cpm_unmask_leg_irq,
> +};
> +
> +/**
> + * xilinx_cpm_pcie_intx_map - Set the handler for the INTx and mark IRQ as valid
> + * @domain: IRQ domain
> + * @irq: Virtual IRQ number
> + * @hwirq: HW interrupt number
> + *
> + * Return: Always returns 0.
> + */
> +static int xilinx_cpm_pcie_intx_map(struct irq_domain *domain,
> + unsigned int irq, irq_hw_number_t hwirq)
> +{
> + irq_set_chip_and_handler(irq, &xilinx_cpm_leg_irq_chip,
> + handle_level_irq);
> + irq_set_chip_data(irq, domain->host_data);
> + irq_set_status_flags(irq, IRQ_LEVEL);
> +
> + return 0;
> +}
> +
> +/* INTx IRQ Domain operations */
> +static const struct irq_domain_ops intx_domain_ops = {
> + .map = xilinx_cpm_pcie_intx_map,
> +};
> +
> +/**
> + * xilinx_cpm_pcie_intr_handler - Interrupt Service Handler
> + * @irq: IRQ number
> + * @data: PCIe port information
> + *
> + * Return: IRQ_HANDLED on success and IRQ_NONE on failure
> + */
> +static irqreturn_t xilinx_cpm_pcie_intr_handler(int irq, void *data)
> +{
> + struct xilinx_cpm_pcie_port *port = data;
> + struct device *dev = port->dev;
> + u32 val, mask, status, bit;
> + unsigned long intr_val;
> +
> + /* Read interrupt decode and mask registers */
> + val = pcie_read(port, XILINX_CPM_PCIE_REG_IDR);
> + mask = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
> +
> + status = val & mask;
> + if (!status)
> + return IRQ_NONE;
> +
> + if (status & XILINX_CPM_PCIE_INTR_LINK_DOWN)
> + dev_warn(dev, "Link Down\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_HOT_RESET)
> + dev_info(dev, "Hot reset\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_CFG_TIMEOUT)
> + dev_warn(dev, "ECAM access timeout\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_CORRECTABLE) {
> + dev_warn(dev, "Correctable error message\n");
> + cpm_pcie_clear_err_interrupts(port);
> + }
> +
> + if (status & XILINX_CPM_PCIE_INTR_NONFATAL) {
> + dev_warn(dev, "Non fatal error message\n");
> + cpm_pcie_clear_err_interrupts(port);
> + }
> +
> + if (status & XILINX_CPM_PCIE_INTR_FATAL) {
> + dev_warn(dev, "Fatal error message\n");
> + cpm_pcie_clear_err_interrupts(port);
> + }
> +
> + if (status & XILINX_CPM_PCIE_INTR_INTX) {
> + /* Handle INTx Interrupt */
> + intr_val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN);
> + intr_val = intr_val >> XILINX_CPM_PCIE_IDRN_SHIFT;
> +
> + for_each_set_bit(bit, &intr_val, PCI_NUM_INTX)
> + generic_handle_irq(irq_find_mapping(port->leg_domain,
> + bit));
> + }
> +
> + if (status & XILINX_CPM_PCIE_INTR_SLV_UNSUPP)
> + dev_warn(dev, "Slave unsupported request\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_SLV_UNEXP)
> + dev_warn(dev, "Slave unexpected completion\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_SLV_COMPL)
> + dev_warn(dev, "Slave completion timeout\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_SLV_ERRP)
> + dev_warn(dev, "Slave Error Poison\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_SLV_CMPABT)
> + dev_warn(dev, "Slave Completer Abort\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_SLV_ILLBUR)
> + dev_warn(dev, "Slave Illegal Burst\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_MST_DECERR)
> + dev_warn(dev, "Master decode error\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_MST_SLVERR)
> + dev_warn(dev, "Master slave error\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_CFG_PCIE_TIMEOUT)
> + dev_warn(dev, "PCIe ECAM access timeout\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_CFG_ERR_POISON)
> + dev_warn(dev, "ECAM poisoned completion received\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_PME_TO_ACK_RCVD)
> + dev_warn(dev, "PME_TO_ACK message received\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_PM_PME_RCVD)
> + dev_warn(dev, "PM_PME message received\n");
> +
> + if (status & XILINX_CPM_PCIE_INTR_SLV_PCIE_TIMEOUT)
> + dev_warn(dev, "PCIe completion timeout received\n");
> +
> + /* Clear the Interrupt Decode register */
> + pcie_write(port, status, XILINX_CPM_PCIE_REG_IDR);
> +
> + /*
> + * XILINX_CPM_PCIE_MISC_IR_STATUS register is mapped to
> + * CPM SLCR block.
> + */
> + val = readl(port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
> + if (val)
> + writel(val, port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
> +
> + return IRQ_HANDLED;
> +}
> +
> +/**
> + * xilinx_cpm_pcie_init_irq_domain - Initialize IRQ domain
> + * @port: PCIe port information
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_cpm_pcie_init_irq_domain(struct xilinx_cpm_pcie_port *port)
> +{
> + struct device *dev = port->dev;
> + struct device_node *node = dev->of_node;
> + struct device_node *pcie_intc_node;
> +
> + /* Setup INTx */
> + pcie_intc_node = of_get_next_child(node, NULL);
> + if (!pcie_intc_node) {
> + dev_err(dev, "No PCIe Intc node found\n");
> + return -EINVAL;
> + }
> +
> + port->leg_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
> + &intx_domain_ops,
> + port);
> + of_node_put(pcie_intc_node);
> + if (!port->leg_domain) {
> + dev_err(dev, "Failed to get a INTx IRQ domain\n");
> + return -ENOMEM;
> + }
> +
> + raw_spin_lock_init(&port->leg_mask_lock);
> + return 0;
> +}
> +
> +/**
> + * xilinx_cpm_pcie_init_port - Initialize hardware
> + * @port: PCIe port information
> + */
> +static void xilinx_cpm_pcie_init_port(struct xilinx_cpm_pcie_port *port)
> +{
> + if (cpm_pcie_link_up(port))
> + dev_info(port->dev, "PCIe Link is UP\n");
> + else
> + dev_info(port->dev, "PCIe Link is DOWN\n");
> +
> + /* Disable all interrupts */
> + pcie_write(port, ~XILINX_CPM_PCIE_IDR_ALL_MASK,
> + XILINX_CPM_PCIE_REG_IMR);
> +
> + /* Clear pending interrupts */
> + pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_IDR) &
> + XILINX_CPM_PCIE_IMR_ALL_MASK,
> + XILINX_CPM_PCIE_REG_IDR);
> +
> + /* Enable all interrupts */
> + pcie_write(port, XILINX_CPM_PCIE_IMR_ALL_MASK,
> + XILINX_CPM_PCIE_REG_IMR);
> + pcie_write(port, XILINX_CPM_PCIE_IDRN_MASK,
> + XILINX_CPM_PCIE_REG_IDRN_MASK);
> +
> + /*
> + * XILINX_CPM_PCIE_MISC_IR_ENABLE register is mapped to
> + * CPM SLCR block.
> + */
> + writel(XILINX_CPM_PCIE_MISC_IR_LOCAL,
> + port->cpm_base + XILINX_CPM_PCIE_MISC_IR_ENABLE);
> + /* Enable the Bridge enable bit */
> + pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_RPSC) |
> + XILINX_CPM_PCIE_REG_RPSC_BEN,
> + XILINX_CPM_PCIE_REG_RPSC);
> +}
> +
> +static int xilinx_cpm_request_misc_irq(struct xilinx_cpm_pcie_port *port)
> +{
> + struct device *dev = port->dev;
> + struct platform_device *pdev = to_platform_device(dev);
> + int err;
> +
> + port->irq_misc = platform_get_irq_byname(pdev, "misc");
> + if (port->irq_misc <= 0) {
> + dev_err(dev, "Unable to find misc IRQ line\n");
> + return port->irq_misc;
> + }
> + err = devm_request_irq(dev, port->irq_misc,
> + xilinx_cpm_pcie_intr_handler,
> + IRQF_SHARED | IRQF_NO_THREAD,
> + "xilinx-pcie", port);
> + if (err) {
> + dev_err(dev, "unable to request misc IRQ line %d\n",
> + port->irq_misc);
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * xilinx_cpm_pcie_parse_dt - Parse Device tree
> + * @port: PCIe port information
> + * @bus_range: Bus resource
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_cpm_pcie_parse_dt(struct xilinx_cpm_pcie_port *port,
> + struct resource *bus_range)
> +{
> + struct device *dev = port->dev;
> + struct platform_device *pdev = to_platform_device(dev);
> + struct resource *res;
> + int err;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> + if (res) {
if (!res)
return -ENXIO;
Less indentation and no need for 'else'.
> + port->cfg = pci_ecam_create(dev, res, bus_range,
> + &pci_generic_ecam_ops);
> + if (IS_ERR(port->cfg))
> + return PTR_ERR(port->cfg);
> + } else {
> + return -ENXIO;
> + }
> + port->reg_base = port->cfg->win;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> + "cpm_slcr");
> + if (res) {
> + port->cpm_base = devm_ioremap_resource(dev, res);
Use devm_platform_ioremap_resource_byname()
> + if (IS_ERR(port->cpm_base))
> + return PTR_ERR(port->cpm_base);
> + } else {
> + return -ENXIO;
> + }
> +
> + err = xilinx_cpm_request_misc_irq(port);
> + if (err)
> + return err;
> +
> + return 0;
> +}
> +
> +/**
> + * xilinx_cpm_pcie_probe - Probe function
> + * @pdev: Platform device pointer
> + *
> + * Return: '0' on success and error value on failure
> + */
> +static int xilinx_cpm_pcie_probe(struct platform_device *pdev)
> +{
> + struct xilinx_cpm_pcie_port *port;
> + struct device *dev = &pdev->dev;
> + struct pci_bus *bus;
> + struct pci_bus *child;
> + struct pci_host_bridge *bridge;
> + struct resource *bus_range;
> + int err;
> +
> + bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
> + if (!bridge)
> + return -ENODEV;
> +
> + port = pci_host_bridge_priv(bridge);
> +
> + port->dev = dev;
> +
> + err = pci_parse_request_of_pci_ranges(dev, &bridge->windows,
> + &bridge->dma_ranges, &bus_range);
> + if (err) {
> + dev_err(dev, "Getting bridge resources failed\n");
> + return err;
> + }
> +
> + err = xilinx_cpm_pcie_parse_dt(port, bus_range);
> + if (err) {
> + dev_err(dev, "Parsing DT failed\n");
> + return err;
> + }
> +
> + xilinx_cpm_pcie_init_port(port);
> +
> + err = xilinx_cpm_pcie_init_irq_domain(port);
> + if (err) {
> + dev_err(dev, "Failed creating IRQ Domain\n");
> + return err;
> + }
> +
> + bridge->dev.parent = dev;
> + bridge->sysdata = port->cfg;
> + bridge->busnr = port->root_busno;
> + bridge->ops = &pci_generic_ecam_ops.pci_ops;
> + bridge->map_irq = of_irq_parse_and_map_pci;
> + bridge->swizzle_irq = pci_common_swizzle;
> +
> + err = pci_scan_root_bus_bridge(bridge);
> + if (err) {
> + irq_domain_remove(port->leg_domain);
> + devm_free_irq(dev, port->irq_misc, port);
> + return err;
> + }
> +
> + bus = bridge->bus;
> +
> + pci_assign_unassigned_bus_resources(bus);
> + list_for_each_entry(child, &bus->children, node)
> + pcie_bus_configure_settings(child);
> + pci_bus_add_devices(bus);
All this can use pci_host_probe().
> + return 0;
> +}
> +
> +static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
> + { .compatible = "xlnx,versal-cpm-host-1.00", },
> + {}
> +};
> +
> +static struct platform_driver xilinx_cpm_pcie_driver = {
> + .driver = {
> + .name = "xilinx-cpm-pcie",
> + .of_match_table = xilinx_cpm_pcie_of_match,
> + .suppress_bind_attrs = true,
> + },
> + .probe = xilinx_cpm_pcie_probe,
> +};
> +
> +builtin_platform_driver(xilinx_cpm_pcie_driver);
> --
> 2.7.4
>