drivers/pci/host/pci-dra7xx.c - linux - Git at Google

 /*
  * pcie-dra7xx - PCIe controller driver for TI DRA7xx SoCs
  *
  * Copyright (C) 2013-2014 Texas Instruments Incorporated - http://www.ti.com
  *
  * Authors: Kishon Vijay Abraham I <kishon@ti.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_gpio.h>
 #include <linux/pci.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/resource.h>
 #include <linux/types.h>

 #include "pcie-designware.h"

 /* PCIe controller wrapper DRA7XX configuration registers */

 #define	PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN		0x0024
 #define	PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN		0x0028
 #define	ERR_SYS						BIT(0)
 #define	ERR_FATAL					BIT(1)
 #define	ERR_NONFATAL					BIT(2)
 #define	ERR_COR						BIT(3)
 #define	ERR_AXI						BIT(4)
 #define	ERR_ECRC					BIT(5)
 #define	PME_TURN_OFF					BIT(8)
 #define	PME_TO_ACK					BIT(9)
 #define	PM_PME						BIT(10)
 #define	LINK_REQ_RST					BIT(11)
 #define	LINK_UP_EVT					BIT(12)
 #define	CFG_BME_EVT					BIT(13)
 #define	CFG_MSE_EVT					BIT(14)
 #define	INTERRUPTS (ERR_SYS | ERR_FATAL | ERR_NONFATAL | ERR_COR | ERR_AXI | \
 			ERR_ECRC | PME_TURN_OFF | PME_TO_ACK | PM_PME | \
 			LINK_REQ_RST | LINK_UP_EVT | CFG_BME_EVT | CFG_MSE_EVT)

 #define	PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI		0x0034
 #define	PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI		0x0038
 #define	INTA						BIT(0)
 #define	INTB						BIT(1)
 #define	INTC						BIT(2)
 #define	INTD						BIT(3)
 #define	MSI						BIT(4)
 #define	LEG_EP_INTERRUPTS (INTA | INTB | INTC | INTD)

 #define	PCIECTRL_DRA7XX_CONF_DEVICE_CMD			0x0104
 #define	LTSSM_EN					0x1

 #define	PCIECTRL_DRA7XX_CONF_PHY_CS			0x010C
 #define	LINK_UP						BIT(16)
 #define	DRA7XX_CPU_TO_BUS_ADDR				0x0FFFFFFF

 struct dra7xx_pcie {
 	void __iomem		*base;
 	struct phy		**phy;
 	int			phy_count;
 	struct device		*dev;
 	struct pcie_port	pp;
 };

 #define to_dra7xx_pcie(x)	container_of((x), struct dra7xx_pcie, pp)

 static inline u32 dra7xx_pcie_readl(struct dra7xx_pcie *pcie, u32 offset)
 {
 	return readl(pcie->base + offset);
 }

 static inline void dra7xx_pcie_writel(struct dra7xx_pcie *pcie, u32 offset,
 				      u32 value)
 {
 	writel(value, pcie->base + offset);
 }

 static inline u32 dra7xx_pcie_readl_rc(struct pcie_port *pp, u32 offset)
 {
 	return readl(pp->dbi_base + offset);
 }

 static inline void dra7xx_pcie_writel_rc(struct pcie_port *pp, u32 offset,
 					 u32 value)
 {
 	writel(value, pp->dbi_base + offset);
 }

 static int dra7xx_pcie_link_up(struct pcie_port *pp)
 {
 	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 	u32 reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);

 	return !!(reg & LINK_UP);
 }

 static int dra7xx_pcie_establish_link(struct pcie_port *pp)
 {
 	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 	u32 reg;
 	unsigned int retries;

 	if (dw_pcie_link_up(pp)) {
 		dev_err(pp->dev, "link is already up\n");
 		return 0;
 	}

 	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
 	reg |= LTSSM_EN;
 	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);

 	for (retries = 0; retries < 1000; retries++) {
 		if (dw_pcie_link_up(pp))
 			return 0;
 		usleep_range(10, 20);
 	}

 	dev_err(pp->dev, "link is not up\n");
 	return -EINVAL;
 }

 static void dra7xx_pcie_enable_interrupts(struct pcie_port *pp)
 {
 	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);

 	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN,
 			   ~INTERRUPTS);
 	dra7xx_pcie_writel(dra7xx,
 			   PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN, INTERRUPTS);
 	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI,
 			   ~LEG_EP_INTERRUPTS & ~MSI);

 	if (IS_ENABLED(CONFIG_PCI_MSI))
 		dra7xx_pcie_writel(dra7xx,
 				   PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI, MSI);
 	else
 		dra7xx_pcie_writel(dra7xx,
 				   PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI,
 				   LEG_EP_INTERRUPTS);
 }

 static void dra7xx_pcie_host_init(struct pcie_port *pp)
 {
 	dw_pcie_setup_rc(pp);

 	pp->io_base &= DRA7XX_CPU_TO_BUS_ADDR;
 	pp->mem_base &= DRA7XX_CPU_TO_BUS_ADDR;
 	pp->cfg0_base &= DRA7XX_CPU_TO_BUS_ADDR;
 	pp->cfg1_base &= DRA7XX_CPU_TO_BUS_ADDR;

 	dra7xx_pcie_establish_link(pp);
 	if (IS_ENABLED(CONFIG_PCI_MSI))
 		dw_pcie_msi_init(pp);
 	dra7xx_pcie_enable_interrupts(pp);
 }

 static struct pcie_host_ops dra7xx_pcie_host_ops = {
 	.link_up = dra7xx_pcie_link_up,
 	.host_init = dra7xx_pcie_host_init,
 };

 static int dra7xx_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;
 }

 static const struct irq_domain_ops intx_domain_ops = {
 	.map = dra7xx_pcie_intx_map,
 };

 static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
 {
 	struct device *dev = pp->dev;
 	struct device_node *node = dev->of_node;
 	struct device_node *pcie_intc_node =  of_get_next_child(node, NULL);

 	if (!pcie_intc_node) {
 		dev_err(dev, "No PCIe Intc node found\n");
 		return PTR_ERR(pcie_intc_node);
 	}

 	pp->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
 					       &intx_domain_ops, pp);
 	if (!pp->irq_domain) {
 		dev_err(dev, "Failed to get a INTx IRQ domain\n");
 		return PTR_ERR(pp->irq_domain);
 	}

 	return 0;
 }

 static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
 {
 	struct pcie_port *pp = arg;
 	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
 	u32 reg;

 	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI);

 	switch (reg) {
 	case MSI:
 		dw_handle_msi_irq(pp);
 		break;
 	case INTA:
 	case INTB:
 	case INTC:
 	case INTD:
 		generic_handle_irq(irq_find_mapping(pp->irq_domain, ffs(reg)));
 		break;
 	}

 	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI, reg);

 	return IRQ_HANDLED;
 }


 static irqreturn_t dra7xx_pcie_irq_handler(int irq, void *arg)
 {
 	struct dra7xx_pcie *dra7xx = arg;
 	u32 reg;

 	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN);

 	if (reg & ERR_SYS)
 		dev_dbg(dra7xx->dev, "System Error\n");

 	if (reg & ERR_FATAL)
 		dev_dbg(dra7xx->dev, "Fatal Error\n");

 	if (reg & ERR_NONFATAL)
 		dev_dbg(dra7xx->dev, "Non Fatal Error\n");

 	if (reg & ERR_COR)
 		dev_dbg(dra7xx->dev, "Correctable Error\n");

 	if (reg & ERR_AXI)
 		dev_dbg(dra7xx->dev, "AXI tag lookup fatal Error\n");

 	if (reg & ERR_ECRC)
 		dev_dbg(dra7xx->dev, "ECRC Error\n");

 	if (reg & PME_TURN_OFF)
 		dev_dbg(dra7xx->dev,
 			"Power Management Event Turn-Off message received\n");

 	if (reg & PME_TO_ACK)
 		dev_dbg(dra7xx->dev,
 			"Power Management Turn-Off Ack message received\n");

 	if (reg & PM_PME)
 		dev_dbg(dra7xx->dev,
 			"PM Power Management Event message received\n");

 	if (reg & LINK_REQ_RST)
 		dev_dbg(dra7xx->dev, "Link Request Reset\n");

 	if (reg & LINK_UP_EVT)
 		dev_dbg(dra7xx->dev, "Link-up state change\n");

 	if (reg & CFG_BME_EVT)
 		dev_dbg(dra7xx->dev, "CFG 'Bus Master Enable' change\n");

 	if (reg & CFG_MSE_EVT)
 		dev_dbg(dra7xx->dev, "CFG 'Memory Space Enable' change\n");

 	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN, reg);

 	return IRQ_HANDLED;
 }

 static int __init dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx,
 				       struct platform_device *pdev)
 {
 	int ret;
 	struct pcie_port *pp;
 	struct resource *res;
 	struct device *dev = &pdev->dev;

 	pp = &dra7xx->pp;
 	pp->dev = dev;
 	pp->ops = &dra7xx_pcie_host_ops;

 	pp->irq = platform_get_irq(pdev, 1);
 	if (pp->irq < 0) {
 		dev_err(dev, "missing IRQ resource\n");
 		return -EINVAL;
 	}

 	ret = devm_request_irq(&pdev->dev, pp->irq,
 			       dra7xx_pcie_msi_irq_handler,
 			       IRQF_SHARED | IRQF_NO_THREAD,
 			       "dra7-pcie-msi",	pp);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to request irq\n");
 		return ret;
 	}

 	if (!IS_ENABLED(CONFIG_PCI_MSI)) {
 		ret = dra7xx_pcie_init_irq_domain(pp);
 		if (ret < 0)
 			return ret;
 	}

 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics");
 	pp->dbi_base = devm_ioremap(dev, res->start, resource_size(res));
 	if (!pp->dbi_base)
 		return -ENOMEM;

 	ret = dw_pcie_host_init(pp);
 	if (ret) {
 		dev_err(dra7xx->dev, "failed to initialize host\n");
 		return ret;
 	}

 	return 0;
 }

 static int __init dra7xx_pcie_probe(struct platform_device *pdev)
 {
 	u32 reg;
 	int ret;
 	int irq;
 	int i;
 	int phy_count;
 	struct phy **phy;
 	void __iomem *base;
 	struct resource *res;
 	struct dra7xx_pcie *dra7xx;
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
 	char name[10];
 	int gpio_sel;
 	enum of_gpio_flags flags;
 	unsigned long gpio_flags;

 	dra7xx = devm_kzalloc(dev, sizeof(*dra7xx), GFP_KERNEL);
 	if (!dra7xx)
 		return -ENOMEM;

 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
 		dev_err(dev, "missing IRQ resource\n");
 		return -EINVAL;
 	}

 	ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
 			       IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
 	if (ret) {
 		dev_err(dev, "failed to request irq\n");
 		return ret;
 	}

 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf");
 	base = devm_ioremap_nocache(dev, res->start, resource_size(res));
 	if (!base)
 		return -ENOMEM;

 	phy_count = of_property_count_strings(np, "phy-names");
 	if (phy_count < 0) {
 		dev_err(dev, "unable to find the strings\n");
 		return phy_count;
 	}

 	phy = devm_kzalloc(dev, sizeof(*phy) * phy_count, GFP_KERNEL);
 	if (!phy)
 		return -ENOMEM;

 	for (i = 0; i < phy_count; i++) {
 		snprintf(name, sizeof(name), "pcie-phy%d", i);
 		phy[i] = devm_phy_get(dev, name);
 		if (IS_ERR(phy[i]))
 			return PTR_ERR(phy[i]);

 		ret = phy_init(phy[i]);
 		if (ret < 0)
 			goto err_phy;

 		ret = phy_power_on(phy[i]);
 		if (ret < 0) {
 			phy_exit(phy[i]);
 			goto err_phy;
 		}
 	}

 	dra7xx->base = base;
 	dra7xx->phy = phy;
 	dra7xx->dev = dev;
 	dra7xx->phy_count = phy_count;

 	pm_runtime_enable(dev);
 	ret = pm_runtime_get_sync(dev);
 	if (ret < 0) {
 		dev_err(dev, "pm_runtime_get_sync failed\n");
 		goto err_get_sync;
 	}

 	gpio_sel = of_get_gpio_flags(dev->of_node, 0, &flags);
 	if (gpio_is_valid(gpio_sel)) {
 		gpio_flags = (flags & OF_GPIO_ACTIVE_LOW) ?
 				GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
 		ret = devm_gpio_request_one(dev, gpio_sel, gpio_flags,
 					    "pcie_reset");
 		if (ret) {
 			dev_err(&pdev->dev, "gpio%d request failed, ret %d\n",
 				gpio_sel, ret);
 			goto err_gpio;
 		}
 	} else if (gpio_sel == -EPROBE_DEFER) {
 		ret = -EPROBE_DEFER;
 		goto err_gpio;
 	}

 	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
 	reg &= ~LTSSM_EN;
 	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);

 	platform_set_drvdata(pdev, dra7xx);

 	ret = dra7xx_add_pcie_port(dra7xx, pdev);
 	if (ret < 0)
 		goto err_gpio;

 	return 0;

 err_gpio:
 	pm_runtime_put(dev);

 err_get_sync:
 	pm_runtime_disable(dev);

 err_phy:
 	while (--i >= 0) {
 		phy_power_off(phy[i]);
 		phy_exit(phy[i]);
 	}

 	return ret;
 }

 static int __exit dra7xx_pcie_remove(struct platform_device *pdev)
 {
 	struct dra7xx_pcie *dra7xx = platform_get_drvdata(pdev);
 	struct pcie_port *pp = &dra7xx->pp;
 	struct device *dev = &pdev->dev;
 	int count = dra7xx->phy_count;

 	if (pp->irq_domain)
 		irq_domain_remove(pp->irq_domain);
 	pm_runtime_put(dev);
 	pm_runtime_disable(dev);
 	while (count--) {
 		phy_power_off(dra7xx->phy[count]);
 		phy_exit(dra7xx->phy[count]);
 	}

 	return 0;
 }

 #ifdef CONFIG_PM_SLEEP
 static int dra7xx_pcie_suspend(struct device *dev)
 {
 	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 	struct pcie_port *pp = &dra7xx->pp;
 	u32 val;

 	/* clear MSE */
 	val = dra7xx_pcie_readl_rc(pp, PCI_COMMAND);
 	val &= ~PCI_COMMAND_MEMORY;
 	dra7xx_pcie_writel_rc(pp, PCI_COMMAND, val);

 	return 0;
 }

 static int dra7xx_pcie_resume(struct device *dev)
 {
 	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 	struct pcie_port *pp = &dra7xx->pp;
 	u32 val;

 	/* set MSE */
 	val = dra7xx_pcie_readl_rc(pp, PCI_COMMAND);
 	val |= PCI_COMMAND_MEMORY;
 	dra7xx_pcie_writel_rc(pp, PCI_COMMAND, val);

 	return 0;
 }

 static int dra7xx_pcie_suspend_noirq(struct device *dev)
 {
 	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 	int count = dra7xx->phy_count;

 	while (count--) {
 		phy_power_off(dra7xx->phy[count]);
 		phy_exit(dra7xx->phy[count]);
 	}

 	return 0;
 }

 static int dra7xx_pcie_resume_noirq(struct device *dev)
 {
 	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
 	int phy_count = dra7xx->phy_count;
 	int ret;
 	int i;

 	for (i = 0; i < phy_count; i++) {
 		ret = phy_init(dra7xx->phy[i]);
 		if (ret < 0)
 			goto err_phy;

 		ret = phy_power_on(dra7xx->phy[i]);
 		if (ret < 0) {
 			phy_exit(dra7xx->phy[i]);
 			goto err_phy;
 		}
 	}

 	return 0;

 err_phy:
 	while (--i >= 0) {
 		phy_power_off(dra7xx->phy[i]);
 		phy_exit(dra7xx->phy[i]);
 	}

 	return ret;
 }
 #endif

 static const struct dev_pm_ops dra7xx_pcie_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(dra7xx_pcie_suspend, dra7xx_pcie_resume)
 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(dra7xx_pcie_suspend_noirq,
 				      dra7xx_pcie_resume_noirq)
 };

 static const struct of_device_id of_dra7xx_pcie_match[] = {
 	{ .compatible = "ti,dra7-pcie", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, of_dra7xx_pcie_match);

 static struct platform_driver dra7xx_pcie_driver = {
 	.remove		= __exit_p(dra7xx_pcie_remove),
 	.driver = {
 		.name	= "dra7-pcie",
 		.of_match_table = of_dra7xx_pcie_match,
 		.pm	= &dra7xx_pcie_pm_ops,
 	},
 };

 module_platform_driver_probe(dra7xx_pcie_driver, dra7xx_pcie_probe);

 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
 MODULE_DESCRIPTION("TI PCIe controller driver");
 MODULE_LICENSE("GPL v2");
	/*
	* pcie-dra7xx - PCIe controller driver for TI DRA7xx SoCs
	*
	* Copyright (C) 2013-2014 Texas Instruments Incorporated - http://www.ti.com
	*
	* Authors: Kishon Vijay Abraham I <kishon@ti.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/delay.h>
	#include <linux/err.h>
	#include <linux/interrupt.h>
	#include <linux/irq.h>
	#include <linux/irqdomain.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of_gpio.h>
	#include <linux/pci.h>
	#include <linux/phy/phy.h>
	#include <linux/platform_device.h>
	#include <linux/pm_runtime.h>
	#include <linux/resource.h>
	#include <linux/types.h>

	#include "pcie-designware.h"

	/* PCIe controller wrapper DRA7XX configuration registers */

	#define PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN 0x0024
	#define PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN 0x0028
	#define ERR_SYS BIT(0)
	#define ERR_FATAL BIT(1)
	#define ERR_NONFATAL BIT(2)
	#define ERR_COR BIT(3)
	#define ERR_AXI BIT(4)
	#define ERR_ECRC BIT(5)
	#define PME_TURN_OFF BIT(8)
	#define PME_TO_ACK BIT(9)
	#define PM_PME BIT(10)
	#define LINK_REQ_RST BIT(11)
	#define LINK_UP_EVT BIT(12)
	#define CFG_BME_EVT BIT(13)
	#define CFG_MSE_EVT BIT(14)
	#define INTERRUPTS (ERR_SYS \| ERR_FATAL \| ERR_NONFATAL \| ERR_COR \| ERR_AXI \| \
	ERR_ECRC \| PME_TURN_OFF \| PME_TO_ACK \| PM_PME \| \
	LINK_REQ_RST \| LINK_UP_EVT \| CFG_BME_EVT \| CFG_MSE_EVT)

	#define PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI 0x0034
	#define PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI 0x0038
	#define INTA BIT(0)
	#define INTB BIT(1)
	#define INTC BIT(2)
	#define INTD BIT(3)
	#define MSI BIT(4)
	#define LEG_EP_INTERRUPTS (INTA \| INTB \| INTC \| INTD)

	#define PCIECTRL_DRA7XX_CONF_DEVICE_CMD 0x0104
	#define LTSSM_EN 0x1

	#define PCIECTRL_DRA7XX_CONF_PHY_CS 0x010C
	#define LINK_UP BIT(16)
	#define DRA7XX_CPU_TO_BUS_ADDR 0x0FFFFFFF

	struct dra7xx_pcie {
	void __iomem *base;
	struct phy **phy;
	int phy_count;
	struct device *dev;
	struct pcie_port pp;
	};

	#define to_dra7xx_pcie(x) container_of((x), struct dra7xx_pcie, pp)

	static inline u32 dra7xx_pcie_readl(struct dra7xx_pcie *pcie, u32 offset)
	{
	return readl(pcie->base + offset);
	}

	static inline void dra7xx_pcie_writel(struct dra7xx_pcie *pcie, u32 offset,
	u32 value)
	{
	writel(value, pcie->base + offset);
	}

	static inline u32 dra7xx_pcie_readl_rc(struct pcie_port *pp, u32 offset)
	{
	return readl(pp->dbi_base + offset);
	}

	static inline void dra7xx_pcie_writel_rc(struct pcie_port *pp, u32 offset,
	u32 value)
	{
	writel(value, pp->dbi_base + offset);
	}

	static int dra7xx_pcie_link_up(struct pcie_port *pp)
	{
	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
	u32 reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_PHY_CS);

	return !!(reg & LINK_UP);
	}

	static int dra7xx_pcie_establish_link(struct pcie_port *pp)
	{
	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
	u32 reg;
	unsigned int retries;

	if (dw_pcie_link_up(pp)) {
	dev_err(pp->dev, "link is already up\n");
	return 0;
	}

	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
	reg \|= LTSSM_EN;
	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);

	for (retries = 0; retries < 1000; retries++) {
	if (dw_pcie_link_up(pp))
	return 0;
	usleep_range(10, 20);
	}

	dev_err(pp->dev, "link is not up\n");
	return -EINVAL;
	}

	static void dra7xx_pcie_enable_interrupts(struct pcie_port *pp)
	{
	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);

	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN,
	~INTERRUPTS);
	dra7xx_pcie_writel(dra7xx,
	PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MAIN, INTERRUPTS);
	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI,
	~LEG_EP_INTERRUPTS & ~MSI);

	if (IS_ENABLED(CONFIG_PCI_MSI))
	dra7xx_pcie_writel(dra7xx,
	PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI, MSI);
	else
	dra7xx_pcie_writel(dra7xx,
	PCIECTRL_DRA7XX_CONF_IRQENABLE_SET_MSI,
	LEG_EP_INTERRUPTS);
	}

	static void dra7xx_pcie_host_init(struct pcie_port *pp)
	{
	dw_pcie_setup_rc(pp);

	pp->io_base &= DRA7XX_CPU_TO_BUS_ADDR;
	pp->mem_base &= DRA7XX_CPU_TO_BUS_ADDR;
	pp->cfg0_base &= DRA7XX_CPU_TO_BUS_ADDR;
	pp->cfg1_base &= DRA7XX_CPU_TO_BUS_ADDR;

	dra7xx_pcie_establish_link(pp);
	if (IS_ENABLED(CONFIG_PCI_MSI))
	dw_pcie_msi_init(pp);
	dra7xx_pcie_enable_interrupts(pp);
	}

	static struct pcie_host_ops dra7xx_pcie_host_ops = {
	.link_up = dra7xx_pcie_link_up,
	.host_init = dra7xx_pcie_host_init,
	};

	static int dra7xx_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;
	}

	static const struct irq_domain_ops intx_domain_ops = {
	.map = dra7xx_pcie_intx_map,
	};

	static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
	{
	struct device *dev = pp->dev;
	struct device_node *node = dev->of_node;
	struct device_node *pcie_intc_node = of_get_next_child(node, NULL);

	if (!pcie_intc_node) {
	dev_err(dev, "No PCIe Intc node found\n");
	return PTR_ERR(pcie_intc_node);
	}

	pp->irq_domain = irq_domain_add_linear(pcie_intc_node, 4,
	&intx_domain_ops, pp);
	if (!pp->irq_domain) {
	dev_err(dev, "Failed to get a INTx IRQ domain\n");
	return PTR_ERR(pp->irq_domain);
	}

	return 0;
	}

	static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
	{
	struct pcie_port *pp = arg;
	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pp);
	u32 reg;

	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI);

	switch (reg) {
	case MSI:
	dw_handle_msi_irq(pp);
	break;
	case INTA:
	case INTB:
	case INTC:
	case INTD:
	generic_handle_irq(irq_find_mapping(pp->irq_domain, ffs(reg)));
	break;
	}

	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI, reg);

	return IRQ_HANDLED;
	}


	static irqreturn_t dra7xx_pcie_irq_handler(int irq, void *arg)
	{
	struct dra7xx_pcie *dra7xx = arg;
	u32 reg;

	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN);

	if (reg & ERR_SYS)
	dev_dbg(dra7xx->dev, "System Error\n");

	if (reg & ERR_FATAL)
	dev_dbg(dra7xx->dev, "Fatal Error\n");

	if (reg & ERR_NONFATAL)
	dev_dbg(dra7xx->dev, "Non Fatal Error\n");

	if (reg & ERR_COR)
	dev_dbg(dra7xx->dev, "Correctable Error\n");

	if (reg & ERR_AXI)
	dev_dbg(dra7xx->dev, "AXI tag lookup fatal Error\n");

	if (reg & ERR_ECRC)
	dev_dbg(dra7xx->dev, "ECRC Error\n");

	if (reg & PME_TURN_OFF)
	dev_dbg(dra7xx->dev,
	"Power Management Event Turn-Off message received\n");

	if (reg & PME_TO_ACK)
	dev_dbg(dra7xx->dev,
	"Power Management Turn-Off Ack message received\n");

	if (reg & PM_PME)
	dev_dbg(dra7xx->dev,
	"PM Power Management Event message received\n");

	if (reg & LINK_REQ_RST)
	dev_dbg(dra7xx->dev, "Link Request Reset\n");

	if (reg & LINK_UP_EVT)
	dev_dbg(dra7xx->dev, "Link-up state change\n");

	if (reg & CFG_BME_EVT)
	dev_dbg(dra7xx->dev, "CFG 'Bus Master Enable' change\n");

	if (reg & CFG_MSE_EVT)
	dev_dbg(dra7xx->dev, "CFG 'Memory Space Enable' change\n");

	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MAIN, reg);

	return IRQ_HANDLED;
	}

	static int __init dra7xx_add_pcie_port(struct dra7xx_pcie *dra7xx,
	struct platform_device *pdev)
	{
	int ret;
	struct pcie_port *pp;
	struct resource *res;
	struct device *dev = &pdev->dev;

	pp = &dra7xx->pp;
	pp->dev = dev;
	pp->ops = &dra7xx_pcie_host_ops;

	pp->irq = platform_get_irq(pdev, 1);
	if (pp->irq < 0) {
	dev_err(dev, "missing IRQ resource\n");
	return -EINVAL;
	}

	ret = devm_request_irq(&pdev->dev, pp->irq,
	dra7xx_pcie_msi_irq_handler,
	IRQF_SHARED \| IRQF_NO_THREAD,
	"dra7-pcie-msi", pp);
	if (ret) {
	dev_err(&pdev->dev, "failed to request irq\n");
	return ret;
	}

	if (!IS_ENABLED(CONFIG_PCI_MSI)) {
	ret = dra7xx_pcie_init_irq_domain(pp);
	if (ret < 0)
	return ret;
	}

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rc_dbics");
	pp->dbi_base = devm_ioremap(dev, res->start, resource_size(res));
	if (!pp->dbi_base)
	return -ENOMEM;

	ret = dw_pcie_host_init(pp);
	if (ret) {
	dev_err(dra7xx->dev, "failed to initialize host\n");
	return ret;
	}

	return 0;
	}

	static int __init dra7xx_pcie_probe(struct platform_device *pdev)
	{
	u32 reg;
	int ret;
	int irq;
	int i;
	int phy_count;
	struct phy **phy;
	void __iomem *base;
	struct resource *res;
	struct dra7xx_pcie *dra7xx;
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	char name[10];
	int gpio_sel;
	enum of_gpio_flags flags;
	unsigned long gpio_flags;

	dra7xx = devm_kzalloc(dev, sizeof(*dra7xx), GFP_KERNEL);
	if (!dra7xx)
	return -ENOMEM;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
	dev_err(dev, "missing IRQ resource\n");
	return -EINVAL;
	}

	ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
	IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
	if (ret) {
	dev_err(dev, "failed to request irq\n");
	return ret;
	}

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ti_conf");
	base = devm_ioremap_nocache(dev, res->start, resource_size(res));
	if (!base)
	return -ENOMEM;

	phy_count = of_property_count_strings(np, "phy-names");
	if (phy_count < 0) {
	dev_err(dev, "unable to find the strings\n");
	return phy_count;
	}

	phy = devm_kzalloc(dev, sizeof(phy) phy_count, GFP_KERNEL);
	if (!phy)
	return -ENOMEM;

	for (i = 0; i < phy_count; i++) {
	snprintf(name, sizeof(name), "pcie-phy%d", i);
	phy[i] = devm_phy_get(dev, name);
	if (IS_ERR(phy[i]))
	return PTR_ERR(phy[i]);

	ret = phy_init(phy[i]);
	if (ret < 0)
	goto err_phy;

	ret = phy_power_on(phy[i]);
	if (ret < 0) {
	phy_exit(phy[i]);
	goto err_phy;
	}
	}

	dra7xx->base = base;
	dra7xx->phy = phy;
	dra7xx->dev = dev;
	dra7xx->phy_count = phy_count;

	pm_runtime_enable(dev);
	ret = pm_runtime_get_sync(dev);
	if (ret < 0) {
	dev_err(dev, "pm_runtime_get_sync failed\n");
	goto err_get_sync;
	}

	gpio_sel = of_get_gpio_flags(dev->of_node, 0, &flags);
	if (gpio_is_valid(gpio_sel)) {
	gpio_flags = (flags & OF_GPIO_ACTIVE_LOW) ?
	GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
	ret = devm_gpio_request_one(dev, gpio_sel, gpio_flags,
	"pcie_reset");
	if (ret) {
	dev_err(&pdev->dev, "gpio%d request failed, ret %d\n",
	gpio_sel, ret);
	goto err_gpio;
	}
	} else if (gpio_sel == -EPROBE_DEFER) {
	ret = -EPROBE_DEFER;
	goto err_gpio;
	}

	reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD);
	reg &= ~LTSSM_EN;
	dra7xx_pcie_writel(dra7xx, PCIECTRL_DRA7XX_CONF_DEVICE_CMD, reg);

	platform_set_drvdata(pdev, dra7xx);

	ret = dra7xx_add_pcie_port(dra7xx, pdev);
	if (ret < 0)
	goto err_gpio;

	return 0;

	err_gpio:
	pm_runtime_put(dev);

	err_get_sync:
	pm_runtime_disable(dev);

	err_phy:
	while (--i >= 0) {
	phy_power_off(phy[i]);
	phy_exit(phy[i]);
	}

	return ret;
	}

	static int __exit dra7xx_pcie_remove(struct platform_device *pdev)
	{
	struct dra7xx_pcie *dra7xx = platform_get_drvdata(pdev);
	struct pcie_port *pp = &dra7xx->pp;
	struct device *dev = &pdev->dev;
	int count = dra7xx->phy_count;

	if (pp->irq_domain)
	irq_domain_remove(pp->irq_domain);
	pm_runtime_put(dev);
	pm_runtime_disable(dev);
	while (count--) {
	phy_power_off(dra7xx->phy[count]);
	phy_exit(dra7xx->phy[count]);
	}

	return 0;
	}

	#ifdef CONFIG_PM_SLEEP
	static int dra7xx_pcie_suspend(struct device *dev)
	{
	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
	struct pcie_port *pp = &dra7xx->pp;
	u32 val;

	/* clear MSE */
	val = dra7xx_pcie_readl_rc(pp, PCI_COMMAND);
	val &= ~PCI_COMMAND_MEMORY;
	dra7xx_pcie_writel_rc(pp, PCI_COMMAND, val);

	return 0;
	}

	static int dra7xx_pcie_resume(struct device *dev)
	{
	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
	struct pcie_port *pp = &dra7xx->pp;
	u32 val;

	/* set MSE */
	val = dra7xx_pcie_readl_rc(pp, PCI_COMMAND);
	val \|= PCI_COMMAND_MEMORY;
	dra7xx_pcie_writel_rc(pp, PCI_COMMAND, val);

	return 0;
	}

	static int dra7xx_pcie_suspend_noirq(struct device *dev)
	{
	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
	int count = dra7xx->phy_count;

	while (count--) {
	phy_power_off(dra7xx->phy[count]);
	phy_exit(dra7xx->phy[count]);
	}

	return 0;
	}

	static int dra7xx_pcie_resume_noirq(struct device *dev)
	{
	struct dra7xx_pcie *dra7xx = dev_get_drvdata(dev);
	int phy_count = dra7xx->phy_count;
	int ret;
	int i;

	for (i = 0; i < phy_count; i++) {
	ret = phy_init(dra7xx->phy[i]);
	if (ret < 0)
	goto err_phy;

	ret = phy_power_on(dra7xx->phy[i]);
	if (ret < 0) {
	phy_exit(dra7xx->phy[i]);
	goto err_phy;
	}
	}

	return 0;

	err_phy:
	while (--i >= 0) {
	phy_power_off(dra7xx->phy[i]);
	phy_exit(dra7xx->phy[i]);
	}

	return ret;
	}
	#endif

	static const struct dev_pm_ops dra7xx_pcie_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(dra7xx_pcie_suspend, dra7xx_pcie_resume)
	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(dra7xx_pcie_suspend_noirq,
	dra7xx_pcie_resume_noirq)
	};

	static const struct of_device_id of_dra7xx_pcie_match[] = {
	{ .compatible = "ti,dra7-pcie", },
	{},
	};
	MODULE_DEVICE_TABLE(of, of_dra7xx_pcie_match);

	static struct platform_driver dra7xx_pcie_driver = {
	.remove = __exit_p(dra7xx_pcie_remove),
	.driver = {
	.name = "dra7-pcie",
	.of_match_table = of_dra7xx_pcie_match,
	.pm = &dra7xx_pcie_pm_ops,
	},
	};

	module_platform_driver_probe(dra7xx_pcie_driver, dra7xx_pcie_probe);

	MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
	MODULE_DESCRIPTION("TI PCIe controller driver");
	MODULE_LICENSE("GPL v2");