RE: [PATCH v9 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver

[Bharat Kumar Gogada]

Hi All,

Gentle ping.

Regards,
Bharat

> -----Original Message-----
> From: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxxxxx>
> Sent: Tuesday, June 16, 2020 6:27 PM
> To: linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Cc: bhelgaas@xxxxxxxxxx; lorenzo.pieralisi@xxxxxxx; robh@xxxxxxxxxx;
> maz@xxxxxxxxxx; Bharat Kumar Gogada <bharatku@xxxxxxxxxx>
> Subject: [PATCH v9 2/2] PCI: xilinx-cpm: Add Versal CPM Root Port driver
> 
> - 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 interrupt line.
> 
> Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@xxxxxxxxxx>
> ---
>  drivers/pci/controller/Kconfig           |   8 +
>  drivers/pci/controller/Makefile          |   1 +
>  drivers/pci/controller/pcie-xilinx-cpm.c | 617
> +++++++++++++++++++++++++++++++
>  3 files changed, 626 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..d9e393a 100644
> --- a/drivers/pci/controller/Kconfig
> +++ b/drivers/pci/controller/Kconfig
> @@ -81,6 +81,14 @@ 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"
> +	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.
> +
>  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..2592dbb4
> --- /dev/null
> +++ b/drivers/pci/controller/pcie-xilinx-cpm.c
> @@ -0,0 +1,617 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * PCIe host controller driver for Xilinx Versal CPM DMA Bridge
> + *
> + * (C) Copyright 2019 - 2020, Xilinx, Inc.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/irqchip.h>
> +#include <linux/irqchip/chained_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		0
> +#define XILINX_CPM_PCIE_INTR_HOT_RESET		3
> +#define XILINX_CPM_PCIE_INTR_CFG_PCIE_TIMEOUT	4
> +#define XILINX_CPM_PCIE_INTR_CFG_TIMEOUT	8
> +#define XILINX_CPM_PCIE_INTR_CORRECTABLE	9
> +#define XILINX_CPM_PCIE_INTR_NONFATAL		10
> +#define XILINX_CPM_PCIE_INTR_FATAL		11
> +#define XILINX_CPM_PCIE_INTR_CFG_ERR_POISON	12
> +#define XILINX_CPM_PCIE_INTR_PME_TO_ACK_RCVD	15
> +#define XILINX_CPM_PCIE_INTR_INTX		16
> +#define XILINX_CPM_PCIE_INTR_PM_PME_RCVD	17
> +#define XILINX_CPM_PCIE_INTR_SLV_UNSUPP		20
> +#define XILINX_CPM_PCIE_INTR_SLV_UNEXP		21
> +#define XILINX_CPM_PCIE_INTR_SLV_COMPL		22
> +#define XILINX_CPM_PCIE_INTR_SLV_ERRP		23
> +#define XILINX_CPM_PCIE_INTR_SLV_CMPABT		24
> +#define XILINX_CPM_PCIE_INTR_SLV_ILLBUR		25
> +#define XILINX_CPM_PCIE_INTR_MST_DECERR		26
> +#define XILINX_CPM_PCIE_INTR_MST_SLVERR		27
> +#define XILINX_CPM_PCIE_INTR_SLV_PCIE_TIMEOUT	28
> +
> +#define IMR(x) BIT(XILINX_CPM_PCIE_INTR_ ##x)
> +
> +#define XILINX_CPM_PCIE_IMR_ALL_MASK			\
> +	(						\
> +		IMR(LINK_DOWN)		|		\
> +		IMR(HOT_RESET)		|		\
> +		IMR(CFG_PCIE_TIMEOUT)	|		\
> +		IMR(CFG_TIMEOUT)	|		\
> +		IMR(CORRECTABLE)	|		\
> +		IMR(NONFATAL)		|		\
> +		IMR(FATAL)		|		\
> +		IMR(CFG_ERR_POISON)	|		\
> +		IMR(PME_TO_ACK_RCVD)	|		\
> +		IMR(INTX)		|		\
> +		IMR(PM_PME_RCVD)	|		\
> +		IMR(SLV_UNSUPP)		|		\
> +		IMR(SLV_UNEXP)		|		\
> +		IMR(SLV_COMPL)		|		\
> +		IMR(SLV_ERRP)		|		\
> +		IMR(SLV_CMPABT)		|		\
> +		IMR(SLV_ILLBUR)		|		\
> +		IMR(MST_DECERR)		|		\
> +		IMR(MST_SLVERR)		|		\
> +		IMR(SLV_PCIE_TIMEOUT)			\
> +	)
> +
> +#define XILINX_CPM_PCIE_IDR_ALL_MASK		0xFFFFFFFF
> +#define XILINX_CPM_PCIE_IDRN_MASK		GENMASK(19, 16)
> +#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
> + * @dev: Device pointer
> + * @intx_domain: Legacy IRQ domain pointer
> + * @cfg: Holds mappings of config space window
> + * @intx_irq: legacy interrupt number
> + * @irq: Error interrupt number
> + * @lock: lock protecting shared register access  */ struct
> +xilinx_cpm_pcie_port {
> +	void __iomem			*reg_base;
> +	void __iomem			*cpm_base;
> +	struct device			*dev;
> +	struct irq_domain		*intx_domain;
> +	struct irq_domain		*cpm_domain;
> +	struct pci_config_window	*cfg;
> +	int				intx_irq;
> +	int				irq;
> +	raw_spinlock_t			lock;
> +};
> +
> +static u32 pcie_read(struct xilinx_cpm_pcie_port *port, u32 reg) {
> +	return readl_relaxed(port->reg_base + reg); }
> +
> +static void pcie_write(struct xilinx_cpm_pcie_port *port,
> +		       u32 val, u32 reg)
> +{
> +	writel_relaxed(val, port->reg_base + reg); }
> +
> +static 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);
> +}
> +
> +/**
> + * 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 xilinx_cpm_pcie_port *port =
> irq_data_get_irq_chip_data(data);
> +	unsigned long flags;
> +	u32 mask;
> +	u32 val;
> +
> +	mask = BIT(data->hwirq + XILINX_CPM_PCIE_IDRN_SHIFT);
> +	raw_spin_lock_irqsave(&port->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->lock, flags); }
> +
> +static void xilinx_cpm_unmask_leg_irq(struct irq_data *data) {
> +	struct xilinx_cpm_pcie_port *port =
> irq_data_get_irq_chip_data(data);
> +	unsigned long flags;
> +	u32 mask;
> +	u32 val;
> +
> +	mask = BIT(data->hwirq + XILINX_CPM_PCIE_IDRN_SHIFT);
> +	raw_spin_lock_irqsave(&port->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->lock, flags); }
> +
> +static struct irq_chip xilinx_cpm_leg_irq_chip = {
> +	.name		= "INTx",
> +	.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,
> +};
> +
> +static void xilinx_cpm_pcie_intx_flow(struct irq_desc *desc) {
> +	struct xilinx_cpm_pcie_port *port =
> irq_desc_get_handler_data(desc);
> +	struct irq_chip *chip = irq_desc_get_chip(desc);
> +	unsigned long val;
> +	int i;
> +
> +	chained_irq_enter(chip, desc);
> +
> +	val = FIELD_GET(XILINX_CPM_PCIE_IDRN_MASK,
> +			pcie_read(port, XILINX_CPM_PCIE_REG_IDRN));
> +
> +	for_each_set_bit(i, &val, PCI_NUM_INTX)
> +		generic_handle_irq(irq_find_mapping(port->intx_domain, i));
> +
> +	chained_irq_exit(chip, desc);
> +}
> +
> +static void xilinx_cpm_mask_event_irq(struct irq_data *d) {
> +	struct xilinx_cpm_pcie_port *port = irq_data_get_irq_chip_data(d);
> +	u32 val;
> +
> +	raw_spin_lock(&port->lock);
> +	val = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
> +	val &= ~BIT(d->hwirq);
> +	pcie_write(port, val, XILINX_CPM_PCIE_REG_IMR);
> +	raw_spin_unlock(&port->lock);
> +}
> +
> +static void xilinx_cpm_unmask_event_irq(struct irq_data *d) {
> +	struct xilinx_cpm_pcie_port *port = irq_data_get_irq_chip_data(d);
> +	u32 val;
> +
> +	raw_spin_lock(&port->lock);
> +	val = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
> +	val |= BIT(d->hwirq);
> +	pcie_write(port, val, XILINX_CPM_PCIE_REG_IMR);
> +	raw_spin_unlock(&port->lock);
> +}
> +
> +static struct irq_chip xilinx_cpm_event_irq_chip = {
> +	.name		= "RC-Event",
> +	.irq_mask	= xilinx_cpm_mask_event_irq,
> +	.irq_unmask	= xilinx_cpm_unmask_event_irq,
> +};
> +
> +static int xilinx_cpm_pcie_event_map(struct irq_domain *domain,
> +				     unsigned int irq, irq_hw_number_t hwirq)
> {
> +	irq_set_chip_and_handler(irq, &xilinx_cpm_event_irq_chip,
> +				 handle_level_irq);
> +	irq_set_chip_data(irq, domain->host_data);
> +	irq_set_status_flags(irq, IRQ_LEVEL);
> +	return 0;
> +}
> +
> +static const struct irq_domain_ops event_domain_ops = {
> +	.map = xilinx_cpm_pcie_event_map,
> +};
> +
> +static void xilinx_cpm_pcie_event_flow(struct irq_desc *desc) {
> +	struct xilinx_cpm_pcie_port *port =
> irq_desc_get_handler_data(desc);
> +	struct irq_chip *chip = irq_desc_get_chip(desc);
> +	unsigned long val;
> +	int i;
> +
> +	chained_irq_enter(chip, desc);
> +	val =  pcie_read(port, XILINX_CPM_PCIE_REG_IDR);
> +	val &= pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
> +	for_each_set_bit(i, &val, 32)
> +		generic_handle_irq(irq_find_mapping(port->cpm_domain,
> i));
> +	pcie_write(port, val, XILINX_CPM_PCIE_REG_IDR);
> +
> +	/*
> +	 * XILINX_CPM_PCIE_MISC_IR_STATUS register is mapped to
> +	 * CPM SLCR block.
> +	 */
> +	val = readl_relaxed(port->cpm_base +
> XILINX_CPM_PCIE_MISC_IR_STATUS);
> +	if (val)
> +		writel_relaxed(val,
> +			       port->cpm_base +
> XILINX_CPM_PCIE_MISC_IR_STATUS);
> +
> +	chained_irq_exit(chip, desc);
> +}
> +
> +#define _IC(x, s)                              \
> +	[XILINX_CPM_PCIE_INTR_ ## x] = { __stringify(x), s }
> +
> +static const struct {
> +	const char      *sym;
> +	const char      *str;
> +} intr_cause[32] = {
> +	_IC(LINK_DOWN,		"Link Down"),
> +	_IC(HOT_RESET,		"Hot reset"),
> +	_IC(CFG_TIMEOUT,	"ECAM access timeout"),
> +	_IC(CORRECTABLE,	"Correctable error message"),
> +	_IC(NONFATAL,		"Non fatal error message"),
> +	_IC(FATAL,		"Fatal error message"),
> +	_IC(SLV_UNSUPP,		"Slave unsupported request"),
> +	_IC(SLV_UNEXP,		"Slave unexpected completion"),
> +	_IC(SLV_COMPL,		"Slave completion timeout"),
> +	_IC(SLV_ERRP,		"Slave Error Poison"),
> +	_IC(SLV_CMPABT,		"Slave Completer Abort"),
> +	_IC(SLV_ILLBUR,		"Slave Illegal Burst"),
> +	_IC(MST_DECERR,		"Master decode error"),
> +	_IC(MST_SLVERR,		"Master slave error"),
> +	_IC(CFG_PCIE_TIMEOUT,	"PCIe ECAM access timeout"),
> +	_IC(CFG_ERR_POISON,	"ECAM poisoned completion received"),
> +	_IC(PME_TO_ACK_RCVD,	"PME_TO_ACK message received"),
> +	_IC(PM_PME_RCVD,	"PM_PME message received"),
> +	_IC(SLV_PCIE_TIMEOUT,	"PCIe completion timeout received"),
> +};
> +
> +static irqreturn_t xilinx_cpm_pcie_intr_handler(int irq, void *dev_id)
> +{
> +	struct xilinx_cpm_pcie_port *port = dev_id;
> +	struct device *dev = port->dev;
> +	struct irq_data *d;
> +
> +	d = irq_domain_get_irq_data(port->cpm_domain, irq);
> +
> +	switch (d->hwirq) {
> +	case XILINX_CPM_PCIE_INTR_CORRECTABLE:
> +	case XILINX_CPM_PCIE_INTR_NONFATAL:
> +	case XILINX_CPM_PCIE_INTR_FATAL:
> +		cpm_pcie_clear_err_interrupts(port);
> +		fallthrough;
> +
> +	default:
> +		if (intr_cause[d->hwirq].str)
> +			dev_warn(dev, "%s\n", intr_cause[d->hwirq].str);
> +		else
> +			dev_warn(dev, "Unknown IRQ %ld\n", d->hwirq);
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void xilinx_cpm_free_irq_domains(struct xilinx_cpm_pcie_port
> +*port) {
> +	if (port->intx_domain) {
> +		irq_domain_remove(port->intx_domain);
> +		port->intx_domain = NULL;
> +	}
> +
> +	if (port->cpm_domain) {
> +		irq_domain_remove(port->cpm_domain);
> +		port->cpm_domain = NULL;
> +	}
> +}
> +
> +/**
> + * 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->cpm_domain = irq_domain_add_linear(pcie_intc_node, 32,
> +						 &event_domain_ops,
> +						 port);
> +	if (!port->cpm_domain)
> +		goto out;
> +
> +	irq_domain_update_bus_token(port->cpm_domain,
> DOMAIN_BUS_NEXUS);
> +
> +	port->intx_domain = irq_domain_add_linear(pcie_intc_node,
> PCI_NUM_INTX,
> +						  &intx_domain_ops,
> +						  port);
> +	if (!port->intx_domain)
> +		goto out;
> +
> +	irq_domain_update_bus_token(port->intx_domain,
> DOMAIN_BUS_WIRED);
> +
> +	of_node_put(pcie_intc_node);
> +	raw_spin_lock_init(&port->lock);
> +
> +	return 0;
> +out:
> +	xilinx_cpm_free_irq_domains(port);
> +	dev_err(dev, "Failed to allocate IRQ domains\n");
> +
> +	return -ENOMEM;
> +}
> +
> +static int xilinx_cpm_setup_irq(struct xilinx_cpm_pcie_port *port) {
> +	struct device *dev = port->dev;
> +	struct platform_device *pdev = to_platform_device(dev);
> +	int i, irq;
> +
> +	port->irq = platform_get_irq(pdev, 0);
> +	if (port->irq < 0)
> +		return port->irq;
> +
> +	for (i = 0; i < ARRAY_SIZE(intr_cause); i++) {
> +		int err;
> +
> +		if (!intr_cause[i].str)
> +			continue;
> +
> +		irq = irq_create_mapping(port->cpm_domain, i);
> +		if (!irq) {
> +			dev_err(dev, "Failed to map interrupt\n");
> +			return -ENXIO;
> +		}
> +
> +		err = devm_request_irq(dev, irq,
> xilinx_cpm_pcie_intr_handler,
> +				       0, intr_cause[i].sym, port);
> +		if (err) {
> +			dev_err(dev, "Failed to request IRQ %d\n", irq);
> +			return err;
> +		}
> +	}
> +
> +	port->intx_irq = irq_create_mapping(port->cpm_domain,
> +					    XILINX_CPM_PCIE_INTR_INTX);
> +	if (!port->intx_irq) {
> +		dev_err(dev, "Failed to map INTx interrupt\n");
> +		return -ENXIO;
> +	}
> +
> +	/* Plug the INTx chained handler */
> +	irq_set_chained_handler_and_data(port->intx_irq,
> +					 xilinx_cpm_pcie_intx_flow, port);
> +
> +	/* Plug the main event chained handler */
> +	irq_set_chained_handler_and_data(port->irq,
> +					 xilinx_cpm_pcie_event_flow, port);
> +
> +	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);
> +
> +	/*
> +	 * 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);
> +}
> +
> +/**
> + * 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;
> +
> +	port->cpm_base = devm_platform_ioremap_resource_byname(pdev,
> +							       "cpm_slcr");
> +	if (IS_ERR(port->cpm_base))
> +		return PTR_ERR(port->cpm_base);
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
> "cfg");
> +	if (!res)
> +		return -ENXIO;
> +
> +	port->cfg = pci_ecam_create(dev, res, bus_range,
> +				    &pci_generic_ecam_ops);
> +	if (IS_ERR(port->cfg))
> +		return PTR_ERR(port->cfg);
> +
> +	port->reg_base = port->cfg->win;
> +
> +	return 0;
> +}
> +
> +void xilinx_cpm_free_interrupts(struct xilinx_cpm_pcie_port *port) {
> +	irq_set_chained_handler_and_data(port->intx_irq, NULL, NULL);
> +	irq_set_chained_handler_and_data(port->irq, NULL, NULL); }
> +
> +/**
> + * 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_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_init_irq_domain(port);
> +	if (err)
> +		return err;
> +
> +	err = xilinx_cpm_pcie_parse_dt(port, bus_range);
> +	if (err) {
> +		dev_err(dev, "Parsing DT failed\n");
> +		goto err_parse_dt;
> +	}
> +
> +	xilinx_cpm_pcie_init_port(port);
> +
> +	err = xilinx_cpm_setup_irq(port);
> +	if (err) {
> +		dev_err(dev, "Failed to set up interrupts\n");
> +		goto err_setup_irq;
> +	}
> +
> +	bridge->dev.parent = dev;
> +	bridge->sysdata = port->cfg;
> +	bridge->busnr = port->cfg->busr.start;
> +	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_host_probe(bridge);
> +	if (err < 0)
> +		goto err_host_bridge;
> +
> +	return 0;
> +
> +err_host_bridge:
> +	xilinx_cpm_free_interrupts(port);
> +err_setup_irq:
> +	pci_ecam_free(port->cfg);
> +err_parse_dt:
> +	xilinx_cpm_free_irq_domains(port);
> +	return err;
> +}
> +
> +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