PCI: Collect all native drivers under drivers/pci/controller/

Native PCI drivers for root complex devices were originally all in
drivers/pci/host/.  Some of these devices can also be operated in endpoint
mode.  Drivers for endpoint mode didn't seem to fit in the "host"
directory, so we put both the root complex and endpoint drivers in
per-device directories, e.g., drivers/pci/dwc/, drivers/pci/cadence/, etc.

These per-device directories contain trivial Kconfig and Makefiles and
clutter drivers/pci/.  Make a new drivers/pci/controllers/ directory and
collect all the device-specific drivers there.

No functional change intended.

Link: https://lkml.kernel.org/r/1520304202-232891-1-git-send-email-shawn.lin@rock-chips.com
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 702 insertions, 0 deletions

diff --git a/drivers/pci/controller/pcie-xilinx.c b/drivers/pci/controller/pcie-xilinx.c
new file mode 100644
index 000000000000..b110a3a814e3
--- /dev/null
+++ b/drivers/pci/controller/pcie-xilinx.c
@@ -0,0 +1,702 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * PCIe host controller driver for Xilinx AXI PCIe Bridge
+ *
+ * Copyright (c) 2012 - 2014 Xilinx, Inc.
+ *
+ * Based on the Tegra PCIe driver
+ *
+ * Bits taken from Synopsys DesignWare Host controller driver and
+ * ARM PCI Host generic driver.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/msi.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 "../pci.h"
+
+/* Register definitions */
+#define XILINX_PCIE_REG_BIR		0x00000130
+#define XILINX_PCIE_REG_IDR		0x00000138
+#define XILINX_PCIE_REG_IMR		0x0000013c
+#define XILINX_PCIE_REG_PSCR		0x00000144
+#define XILINX_PCIE_REG_RPSC		0x00000148
+#define XILINX_PCIE_REG_MSIBASE1	0x0000014c
+#define XILINX_PCIE_REG_MSIBASE2	0x00000150
+#define XILINX_PCIE_REG_RPEFR		0x00000154
+#define XILINX_PCIE_REG_RPIFR1		0x00000158
+#define XILINX_PCIE_REG_RPIFR2		0x0000015c
+
+/* Interrupt registers definitions */
+#define XILINX_PCIE_INTR_LINK_DOWN	BIT(0)
+#define XILINX_PCIE_INTR_ECRC_ERR	BIT(1)
+#define XILINX_PCIE_INTR_STR_ERR	BIT(2)
+#define XILINX_PCIE_INTR_HOT_RESET	BIT(3)
+#define XILINX_PCIE_INTR_CFG_TIMEOUT	BIT(8)
+#define XILINX_PCIE_INTR_CORRECTABLE	BIT(9)
+#define XILINX_PCIE_INTR_NONFATAL	BIT(10)
+#define XILINX_PCIE_INTR_FATAL		BIT(11)
+#define XILINX_PCIE_INTR_INTX		BIT(16)
+#define XILINX_PCIE_INTR_MSI		BIT(17)
+#define XILINX_PCIE_INTR_SLV_UNSUPP	BIT(20)
+#define XILINX_PCIE_INTR_SLV_UNEXP	BIT(21)
+#define XILINX_PCIE_INTR_SLV_COMPL	BIT(22)
+#define XILINX_PCIE_INTR_SLV_ERRP	BIT(23)
+#define XILINX_PCIE_INTR_SLV_CMPABT	BIT(24)
+#define XILINX_PCIE_INTR_SLV_ILLBUR	BIT(25)
+#define XILINX_PCIE_INTR_MST_DECERR	BIT(26)
+#define XILINX_PCIE_INTR_MST_SLVERR	BIT(27)
+#define XILINX_PCIE_INTR_MST_ERRP	BIT(28)
+#define XILINX_PCIE_IMR_ALL_MASK	0x1FF30FED
+#define XILINX_PCIE_IMR_ENABLE_MASK	0x1FF30F0D
+#define XILINX_PCIE_IDR_ALL_MASK	0xFFFFFFFF
+
+/* Root Port Error FIFO Read Register definitions */
+#define XILINX_PCIE_RPEFR_ERR_VALID	BIT(18)
+#define XILINX_PCIE_RPEFR_REQ_ID	GENMASK(15, 0)
+#define XILINX_PCIE_RPEFR_ALL_MASK	0xFFFFFFFF
+
+/* Root Port Interrupt FIFO Read Register 1 definitions */
+#define XILINX_PCIE_RPIFR1_INTR_VALID	BIT(31)
+#define XILINX_PCIE_RPIFR1_MSI_INTR	BIT(30)
+#define XILINX_PCIE_RPIFR1_INTR_MASK	GENMASK(28, 27)
+#define XILINX_PCIE_RPIFR1_ALL_MASK	0xFFFFFFFF
+#define XILINX_PCIE_RPIFR1_INTR_SHIFT	27
+
+/* Bridge Info Register definitions */
+#define XILINX_PCIE_BIR_ECAM_SZ_MASK	GENMASK(18, 16)
+#define XILINX_PCIE_BIR_ECAM_SZ_SHIFT	16
+
+/* Root Port Interrupt FIFO Read Register 2 definitions */
+#define XILINX_PCIE_RPIFR2_MSG_DATA	GENMASK(15, 0)
+
+/* Root Port Status/control Register definitions */
+#define XILINX_PCIE_REG_RPSC_BEN	BIT(0)
+
+/* Phy Status/Control Register definitions */
+#define XILINX_PCIE_REG_PSCR_LNKUP	BIT(11)
+
+/* ECAM definitions */
+#define ECAM_BUS_NUM_SHIFT		20
+#define ECAM_DEV_NUM_SHIFT		12
+
+/* Number of MSI IRQs */
+#define XILINX_NUM_MSI_IRQS		128
+
+/**
+ * struct xilinx_pcie_port - PCIe port information
+ * @reg_base: IO Mapped Register Base
+ * @irq: Interrupt number
+ * @msi_pages: MSI pages
+ * @root_busno: Root Bus number
+ * @dev: Device pointer
+ * @msi_domain: MSI IRQ domain pointer
+ * @leg_domain: Legacy IRQ domain pointer
+ * @resources: Bus Resources
+ */
+struct xilinx_pcie_port {
+	void __iomem *reg_base;
+	u32 irq;
+	unsigned long msi_pages;
+	u8 root_busno;
+	struct device *dev;
+	struct irq_domain *msi_domain;
+	struct irq_domain *leg_domain;
+	struct list_head resources;
+};
+
+static DECLARE_BITMAP(msi_irq_in_use, XILINX_NUM_MSI_IRQS);
+
+static inline u32 pcie_read(struct xilinx_pcie_port *port, u32 reg)
+{
+	return readl(port->reg_base + reg);
+}
+
+static inline void pcie_write(struct xilinx_pcie_port *port, u32 val, u32 reg)
+{
+	writel(val, port->reg_base + reg);
+}
+
+static inline bool xilinx_pcie_link_up(struct xilinx_pcie_port *port)
+{
+	return (pcie_read(port, XILINX_PCIE_REG_PSCR) &
+		XILINX_PCIE_REG_PSCR_LNKUP) ? 1 : 0;
+}
+
+/**
+ * xilinx_pcie_clear_err_interrupts - Clear Error Interrupts
+ * @port: PCIe port information
+ */
+static void xilinx_pcie_clear_err_interrupts(struct xilinx_pcie_port *port)
+{
+	struct device *dev = port->dev;
+	unsigned long val = pcie_read(port, XILINX_PCIE_REG_RPEFR);
+
+	if (val & XILINX_PCIE_RPEFR_ERR_VALID) {
+		dev_dbg(dev, "Requester ID %lu\n",
+			val & XILINX_PCIE_RPEFR_REQ_ID);
+		pcie_write(port, XILINX_PCIE_RPEFR_ALL_MASK,
+			   XILINX_PCIE_REG_RPEFR);
+	}
+}
+
+/**
+ * xilinx_pcie_valid_device - Check if a valid device is present on bus
+ * @bus: PCI Bus structure
+ * @devfn: device/function
+ *
+ * Return: 'true' on success and 'false' if invalid device is found
+ */
+static bool xilinx_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
+{
+	struct xilinx_pcie_port *port = bus->sysdata;
+
+	/* Check if link is up when trying to access downstream ports */
+	if (bus->number != port->root_busno)
+		if (!xilinx_pcie_link_up(port))
+			return false;
+
+	/* Only one device down on each root port */
+	if (bus->number == port->root_busno && devfn > 0)
+		return false;
+
+	return true;
+}
+
+/**
+ * xilinx_pcie_map_bus - Get configuration base
+ * @bus: PCI Bus structure
+ * @devfn: Device/function
+ * @where: Offset from base
+ *
+ * Return: Base address of the configuration space needed to be
+ *	   accessed.
+ */
+static void __iomem *xilinx_pcie_map_bus(struct pci_bus *bus,
+					 unsigned int devfn, int where)
+{
+	struct xilinx_pcie_port *port = bus->sysdata;
+	int relbus;
+
+	if (!xilinx_pcie_valid_device(bus, devfn))
+		return NULL;
+
+	relbus = (bus->number << ECAM_BUS_NUM_SHIFT) |
+		 (devfn << ECAM_DEV_NUM_SHIFT);
+
+	return port->reg_base + relbus + where;
+}
+
+/* PCIe operations */
+static struct pci_ops xilinx_pcie_ops = {
+	.map_bus = xilinx_pcie_map_bus,
+	.read	= pci_generic_config_read,
+	.write	= pci_generic_config_write,
+};
+
+/* MSI functions */
+
+/**
+ * xilinx_pcie_destroy_msi - Free MSI number
+ * @irq: IRQ to be freed
+ */
+static void xilinx_pcie_destroy_msi(unsigned int irq)
+{
+	struct msi_desc *msi;
+	struct xilinx_pcie_port *port;
+	struct irq_data *d = irq_get_irq_data(irq);
+	irq_hw_number_t hwirq = irqd_to_hwirq(d);
+
+	if (!test_bit(hwirq, msi_irq_in_use)) {
+		msi = irq_get_msi_desc(irq);
+		port = msi_desc_to_pci_sysdata(msi);
+		dev_err(port->dev, "Trying to free unused MSI#%d\n", irq);
+	} else {
+		clear_bit(hwirq, msi_irq_in_use);
+	}
+}
+
+/**
+ * xilinx_pcie_assign_msi - Allocate MSI number
+ *
+ * Return: A valid IRQ on success and error value on failure.
+ */
+static int xilinx_pcie_assign_msi(void)
+{
+	int pos;
+
+	pos = find_first_zero_bit(msi_irq_in_use, XILINX_NUM_MSI_IRQS);
+	if (pos < XILINX_NUM_MSI_IRQS)
+		set_bit(pos, msi_irq_in_use);
+	else
+		return -ENOSPC;
+
+	return pos;
+}
+
+/**
+ * xilinx_msi_teardown_irq - Destroy the MSI
+ * @chip: MSI Chip descriptor
+ * @irq: MSI IRQ to destroy
+ */
+static void xilinx_msi_teardown_irq(struct msi_controller *chip,
+				    unsigned int irq)
+{
+	xilinx_pcie_destroy_msi(irq);
+	irq_dispose_mapping(irq);
+}
+
+/**
+ * xilinx_pcie_msi_setup_irq - Setup MSI request
+ * @chip: MSI chip pointer
+ * @pdev: PCIe device pointer
+ * @desc: MSI descriptor pointer
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_pcie_msi_setup_irq(struct msi_controller *chip,
+				     struct pci_dev *pdev,
+				     struct msi_desc *desc)
+{
+	struct xilinx_pcie_port *port = pdev->bus->sysdata;
+	unsigned int irq;
+	int hwirq;
+	struct msi_msg msg;
+	phys_addr_t msg_addr;
+
+	hwirq = xilinx_pcie_assign_msi();
+	if (hwirq < 0)
+		return hwirq;
+
+	irq = irq_create_mapping(port->msi_domain, hwirq);
+	if (!irq)
+		return -EINVAL;
+
+	irq_set_msi_desc(irq, desc);
+
+	msg_addr = virt_to_phys((void *)port->msi_pages);
+
+	msg.address_hi = 0;
+	msg.address_lo = msg_addr;
+	msg.data = irq;
+
+	pci_write_msi_msg(irq, &msg);
+
+	return 0;
+}
+
+/* MSI Chip Descriptor */
+static struct msi_controller xilinx_pcie_msi_chip = {
+	.setup_irq = xilinx_pcie_msi_setup_irq,
+	.teardown_irq = xilinx_msi_teardown_irq,
+};
+
+/* HW Interrupt Chip Descriptor */
+static struct irq_chip xilinx_msi_irq_chip = {
+	.name = "Xilinx PCIe MSI",
+	.irq_enable = pci_msi_unmask_irq,
+	.irq_disable = pci_msi_mask_irq,
+	.irq_mask = pci_msi_mask_irq,
+	.irq_unmask = pci_msi_unmask_irq,
+};
+
+/**
+ * xilinx_pcie_msi_map - Set the handler for the MSI and mark IRQ as valid
+ * @domain: IRQ domain
+ * @irq: Virtual IRQ number
+ * @hwirq: HW interrupt number
+ *
+ * Return: Always returns 0.
+ */
+static int xilinx_pcie_msi_map(struct irq_domain *domain, unsigned int irq,
+			       irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &xilinx_msi_irq_chip, handle_simple_irq);
+	irq_set_chip_data(irq, domain->host_data);
+
+	return 0;
+}
+
+/* IRQ Domain operations */
+static const struct irq_domain_ops msi_domain_ops = {
+	.map = xilinx_pcie_msi_map,
+};
+
+/**
+ * xilinx_pcie_enable_msi - Enable MSI support
+ * @port: PCIe port information
+ */
+static void xilinx_pcie_enable_msi(struct xilinx_pcie_port *port)
+{
+	phys_addr_t msg_addr;
+
+	port->msi_pages = __get_free_pages(GFP_KERNEL, 0);
+	msg_addr = virt_to_phys((void *)port->msi_pages);
+	pcie_write(port, 0x0, XILINX_PCIE_REG_MSIBASE1);
+	pcie_write(port, msg_addr, XILINX_PCIE_REG_MSIBASE2);
+}
+
+/* INTx Functions */
+
+/**
+ * xilinx_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_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
+				irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_simple_irq);
+	irq_set_chip_data(irq, domain->host_data);
+
+	return 0;
+}
+
+/* INTx IRQ Domain operations */
+static const struct irq_domain_ops intx_domain_ops = {
+	.map = xilinx_pcie_intx_map,
+	.xlate = pci_irqd_intx_xlate,
+};
+
+/* PCIe HW Functions */
+
+/**
+ * xilinx_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_pcie_intr_handler(int irq, void *data)
+{
+	struct xilinx_pcie_port *port = (struct xilinx_pcie_port *)data;
+	struct device *dev = port->dev;
+	u32 val, mask, status;
+
+	/* Read interrupt decode and mask registers */
+	val = pcie_read(port, XILINX_PCIE_REG_IDR);
+	mask = pcie_read(port, XILINX_PCIE_REG_IMR);
+
+	status = val & mask;
+	if (!status)
+		return IRQ_NONE;
+
+	if (status & XILINX_PCIE_INTR_LINK_DOWN)
+		dev_warn(dev, "Link Down\n");
+
+	if (status & XILINX_PCIE_INTR_ECRC_ERR)
+		dev_warn(dev, "ECRC failed\n");
+
+	if (status & XILINX_PCIE_INTR_STR_ERR)
+		dev_warn(dev, "Streaming error\n");
+
+	if (status & XILINX_PCIE_INTR_HOT_RESET)
+		dev_info(dev, "Hot reset\n");
+
+	if (status & XILINX_PCIE_INTR_CFG_TIMEOUT)
+		dev_warn(dev, "ECAM access timeout\n");
+
+	if (status & XILINX_PCIE_INTR_CORRECTABLE) {
+		dev_warn(dev, "Correctable error message\n");
+		xilinx_pcie_clear_err_interrupts(port);
+	}
+
+	if (status & XILINX_PCIE_INTR_NONFATAL) {
+		dev_warn(dev, "Non fatal error message\n");
+		xilinx_pcie_clear_err_interrupts(port);
+	}
+
+	if (status & XILINX_PCIE_INTR_FATAL) {
+		dev_warn(dev, "Fatal error message\n");
+		xilinx_pcie_clear_err_interrupts(port);
+	}
+
+	if (status & (XILINX_PCIE_INTR_INTX | XILINX_PCIE_INTR_MSI)) {
+		val = pcie_read(port, XILINX_PCIE_REG_RPIFR1);
+
+		/* Check whether interrupt valid */
+		if (!(val & XILINX_PCIE_RPIFR1_INTR_VALID)) {
+			dev_warn(dev, "RP Intr FIFO1 read error\n");
+			goto error;
+		}
+
+		/* Decode the IRQ number */
+		if (val & XILINX_PCIE_RPIFR1_MSI_INTR) {
+			val = pcie_read(port, XILINX_PCIE_REG_RPIFR2) &
+				XILINX_PCIE_RPIFR2_MSG_DATA;
+		} else {
+			val = (val & XILINX_PCIE_RPIFR1_INTR_MASK) >>
+				XILINX_PCIE_RPIFR1_INTR_SHIFT;
+			val = irq_find_mapping(port->leg_domain, val);
+		}
+
+		/* Clear interrupt FIFO register 1 */
+		pcie_write(port, XILINX_PCIE_RPIFR1_ALL_MASK,
+			   XILINX_PCIE_REG_RPIFR1);
+
+		/* Handle the interrupt */
+		if (IS_ENABLED(CONFIG_PCI_MSI) ||
+		    !(val & XILINX_PCIE_RPIFR1_MSI_INTR))
+			generic_handle_irq(val);
+	}
+
+	if (status & XILINX_PCIE_INTR_SLV_UNSUPP)
+		dev_warn(dev, "Slave unsupported request\n");
+
+	if (status & XILINX_PCIE_INTR_SLV_UNEXP)
+		dev_warn(dev, "Slave unexpected completion\n");
+
+	if (status & XILINX_PCIE_INTR_SLV_COMPL)
+		dev_warn(dev, "Slave completion timeout\n");
+
+	if (status & XILINX_PCIE_INTR_SLV_ERRP)
+		dev_warn(dev, "Slave Error Poison\n");
+
+	if (status & XILINX_PCIE_INTR_SLV_CMPABT)
+		dev_warn(dev, "Slave Completer Abort\n");
+
+	if (status & XILINX_PCIE_INTR_SLV_ILLBUR)
+		dev_warn(dev, "Slave Illegal Burst\n");
+
+	if (status & XILINX_PCIE_INTR_MST_DECERR)
+		dev_warn(dev, "Master decode error\n");
+
+	if (status & XILINX_PCIE_INTR_MST_SLVERR)
+		dev_warn(dev, "Master slave error\n");
+
+	if (status & XILINX_PCIE_INTR_MST_ERRP)
+		dev_warn(dev, "Master error poison\n");
+
+error:
+	/* Clear the Interrupt Decode register */
+	pcie_write(port, status, XILINX_PCIE_REG_IDR);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * xilinx_pcie_init_irq_domain - Initialize IRQ domain
+ * @port: PCIe port information
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_pcie_init_irq_domain(struct xilinx_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 -ENODEV;
+	}
+
+	port->leg_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
+						 &intx_domain_ops,
+						 port);
+	if (!port->leg_domain) {
+		dev_err(dev, "Failed to get a INTx IRQ domain\n");
+		return -ENODEV;
+	}
+
+	/* Setup MSI */
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		port->msi_domain = irq_domain_add_linear(node,
+							 XILINX_NUM_MSI_IRQS,
+							 &msi_domain_ops,
+							 &xilinx_pcie_msi_chip);
+		if (!port->msi_domain) {
+			dev_err(dev, "Failed to get a MSI IRQ domain\n");
+			return -ENODEV;
+		}
+
+		xilinx_pcie_enable_msi(port);
+	}
+
+	return 0;
+}
+
+/**
+ * xilinx_pcie_init_port - Initialize hardware
+ * @port: PCIe port information
+ */
+static void xilinx_pcie_init_port(struct xilinx_pcie_port *port)
+{
+	struct device *dev = port->dev;
+
+	if (xilinx_pcie_link_up(port))
+		dev_info(dev, "PCIe Link is UP\n");
+	else
+		dev_info(dev, "PCIe Link is DOWN\n");
+
+	/* Disable all interrupts */
+	pcie_write(port, ~XILINX_PCIE_IDR_ALL_MASK,
+		   XILINX_PCIE_REG_IMR);
+
+	/* Clear pending interrupts */
+	pcie_write(port, pcie_read(port, XILINX_PCIE_REG_IDR) &
+			 XILINX_PCIE_IMR_ALL_MASK,
+		   XILINX_PCIE_REG_IDR);
+
+	/* Enable all interrupts we handle */
+	pcie_write(port, XILINX_PCIE_IMR_ENABLE_MASK, XILINX_PCIE_REG_IMR);
+
+	/* Enable the Bridge enable bit */
+	pcie_write(port, pcie_read(port, XILINX_PCIE_REG_RPSC) |
+			 XILINX_PCIE_REG_RPSC_BEN,
+		   XILINX_PCIE_REG_RPSC);
+}
+
+/**
+ * xilinx_pcie_parse_dt - Parse Device tree
+ * @port: PCIe port information
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_pcie_parse_dt(struct xilinx_pcie_port *port)
+{
+	struct device *dev = port->dev;
+	struct device_node *node = dev->of_node;
+	struct resource regs;
+	const char *type;
+	int err;
+
+	type = of_get_property(node, "device_type", NULL);
+	if (!type || strcmp(type, "pci")) {
+		dev_err(dev, "invalid \"device_type\" %s\n", type);
+		return -EINVAL;
+	}
+
+	err = of_address_to_resource(node, 0, &regs);
+	if (err) {
+		dev_err(dev, "missing \"reg\" property\n");
+		return err;
+	}
+
+	port->reg_base = devm_pci_remap_cfg_resource(dev, &regs);
+	if (IS_ERR(port->reg_base))
+		return PTR_ERR(port->reg_base);
+
+	port->irq = irq_of_parse_and_map(node, 0);
+	err = devm_request_irq(dev, port->irq, xilinx_pcie_intr_handler,
+			       IRQF_SHARED | IRQF_NO_THREAD,
+			       "xilinx-pcie", port);
+	if (err) {
+		dev_err(dev, "unable to request irq %d\n", port->irq);
+		return err;
+	}
+
+	return 0;
+}
+
+/**
+ * xilinx_pcie_probe - Probe function
+ * @pdev: Platform device pointer
+ *
+ * Return: '0' on success and error value on failure
+ */
+static int xilinx_pcie_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct xilinx_pcie_port *port;
+	struct pci_bus *bus, *child;
+	struct pci_host_bridge *bridge;
+	int err;
+	resource_size_t iobase = 0;
+	LIST_HEAD(res);
+
+	if (!dev->of_node)
+		return -ENODEV;
+
+	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
+	if (!bridge)
+		return -ENODEV;
+
+	port = pci_host_bridge_priv(bridge);
+
+	port->dev = dev;
+
+	err = xilinx_pcie_parse_dt(port);
+	if (err) {
+		dev_err(dev, "Parsing DT failed\n");
+		return err;
+	}
+
+	xilinx_pcie_init_port(port);
+
+	err = xilinx_pcie_init_irq_domain(port);
+	if (err) {
+		dev_err(dev, "Failed creating IRQ Domain\n");
+		return err;
+	}
+
+	err = devm_of_pci_get_host_bridge_resources(dev, 0, 0xff, &res,
+						    &iobase);
+	if (err) {
+		dev_err(dev, "Getting bridge resources failed\n");
+		return err;
+	}
+
+	err = devm_request_pci_bus_resources(dev, &res);
+	if (err)
+		goto error;
+
+
+	list_splice_init(&res, &bridge->windows);
+	bridge->dev.parent = dev;
+	bridge->sysdata = port;
+	bridge->busnr = 0;
+	bridge->ops = &xilinx_pcie_ops;
+	bridge->map_irq = of_irq_parse_and_map_pci;
+	bridge->swizzle_irq = pci_common_swizzle;
+
+#ifdef CONFIG_PCI_MSI
+	xilinx_pcie_msi_chip.dev = dev;
+	bridge->msi = &xilinx_pcie_msi_chip;
+#endif
+	err = pci_scan_root_bus_bridge(bridge);
+	if (err < 0)
+		goto error;
+
+	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);
+	return 0;
+
+error:
+	pci_free_resource_list(&res);
+	return err;
+}
+
+static const struct of_device_id xilinx_pcie_of_match[] = {
+	{ .compatible = "xlnx,axi-pcie-host-1.00.a", },
+	{}
+};
+
+static struct platform_driver xilinx_pcie_driver = {
+	.driver = {
+		.name = "xilinx-pcie",
+		.of_match_table = xilinx_pcie_of_match,
+		.suppress_bind_attrs = true,
+	},
+	.probe = xilinx_pcie_probe,
+};
+builtin_platform_driver(xilinx_pcie_driver);