diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 16d43cd45619..17a26c17f7f5 100644
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c
@@ -545,6 +545,18 @@ void pci_common_init_dev(struct device *parent, struct hw_pci *hw)
 		 */
 		pci_bus_add_devices(bus);
 	}
+
+	list_for_each_entry(sys, &head, node) {
+		struct pci_bus *bus = sys->bus;
+
+		/* Configure PCI Express settings */
+		if (bus && !pci_has_flag(PCI_PROBE_ONLY)) {
+			struct pci_bus *child;
+
+			list_for_each_entry(child, &bus->children, node)
+				pcie_bus_configure_settings(child);
+		}
+	}
 }
 
 #ifndef CONFIG_PCI_HOST_ITE8152
diff --git a/drivers/edac/i82875p_edac.c b/drivers/edac/i82875p_edac.c
index 8d0450b9b9af..64b68320249f 100644
--- a/drivers/edac/i82875p_edac.c
+++ b/drivers/edac/i82875p_edac.c
@@ -275,7 +275,6 @@ static int i82875p_setup_overfl_dev(struct pci_dev *pdev,
 {
 	struct pci_dev *dev;
 	void __iomem *window;
-	int err;
 
 	*ovrfl_pdev = NULL;
 	*ovrfl_window = NULL;
@@ -293,13 +292,8 @@ static int i82875p_setup_overfl_dev(struct pci_dev *pdev,
 		if (dev == NULL)
 			return 1;
 
-		err = pci_bus_add_device(dev);
-		if (err) {
-			i82875p_printk(KERN_ERR,
-				"%s(): pci_bus_add_device() Failed\n",
-				__func__);
-		}
 		pci_bus_assign_resources(dev->bus);
+		pci_bus_add_device(dev);
 	}
 
 	*ovrfl_pdev = dev;
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index ba2bf55a38df..447d393725e1 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -235,7 +235,7 @@ void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
  *
  * This adds add sysfs entries and start device drivers
  */
-int pci_bus_add_device(struct pci_dev *dev)
+void pci_bus_add_device(struct pci_dev *dev)
 {
 	int retval;
 
@@ -252,8 +252,6 @@ int pci_bus_add_device(struct pci_dev *dev)
 	WARN_ON(retval < 0);
 
 	dev->is_added = 1;
-
-	return 0;
 }
 
 /**
@@ -266,16 +264,12 @@ void pci_bus_add_devices(const struct pci_bus *bus)
 {
 	struct pci_dev *dev;
 	struct pci_bus *child;
-	int retval;
 
 	list_for_each_entry(dev, &bus->devices, bus_list) {
 		/* Skip already-added devices */
 		if (dev->is_added)
 			continue;
-		retval = pci_bus_add_device(dev);
-		if (retval)
-			dev_err(&dev->dev, "Error adding device (%d)\n",
-				retval);
+		pci_bus_add_device(dev);
 	}
 
 	list_for_each_entry(dev, &bus->devices, bus_list) {
diff --git a/drivers/pci/host/pci-exynos.c b/drivers/pci/host/pci-exynos.c
index 81aa700a8ada..1632661c5b7f 100644
--- a/drivers/pci/host/pci-exynos.c
+++ b/drivers/pci/host/pci-exynos.c
@@ -415,9 +415,7 @@ static irqreturn_t exynos_pcie_msi_irq_handler(int irq, void *arg)
 {
 	struct pcie_port *pp = arg;
 
-	dw_handle_msi_irq(pp);
-
-	return IRQ_HANDLED;
+	return dw_handle_msi_irq(pp);
 }
 
 static void exynos_pcie_msi_init(struct pcie_port *pp)
@@ -511,7 +509,8 @@ static struct pcie_host_ops exynos_pcie_host_ops = {
 	.host_init = exynos_pcie_host_init,
 };
 
-static int add_pcie_port(struct pcie_port *pp, struct platform_device *pdev)
+static int __init add_pcie_port(struct pcie_port *pp,
+				struct platform_device *pdev)
 {
 	int ret;
 
diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index ee082509b0ba..a5645ae4aef0 100644
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -25,6 +25,7 @@
 #include <linux/resource.h>
 #include <linux/signal.h>
 #include <linux/types.h>
+#include <linux/interrupt.h>
 
 #include "pcie-designware.h"
 
@@ -32,13 +33,9 @@
 
 struct imx6_pcie {
 	int			reset_gpio;
-	int			power_on_gpio;
-	int			wake_up_gpio;
-	int			disable_gpio;
-	struct clk		*lvds_gate;
-	struct clk		*sata_ref_100m;
-	struct clk		*pcie_ref_125m;
-	struct clk		*pcie_axi;
+	struct clk		*pcie_bus;
+	struct clk		*pcie_phy;
+	struct clk		*pcie;
 	struct pcie_port	pp;
 	struct regmap		*iomuxc_gpr;
 	void __iomem		*mem_base;
@@ -231,36 +228,27 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
 	int ret;
 
-	if (gpio_is_valid(imx6_pcie->power_on_gpio))
-		gpio_set_value(imx6_pcie->power_on_gpio, 1);
-
 	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
 			IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
 	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
 			IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
 
-	ret = clk_prepare_enable(imx6_pcie->sata_ref_100m);
+	ret = clk_prepare_enable(imx6_pcie->pcie_phy);
 	if (ret) {
-		dev_err(pp->dev, "unable to enable sata_ref_100m\n");
-		goto err_sata_ref;
+		dev_err(pp->dev, "unable to enable pcie_phy clock\n");
+		goto err_pcie_phy;
 	}
 
-	ret = clk_prepare_enable(imx6_pcie->pcie_ref_125m);
+	ret = clk_prepare_enable(imx6_pcie->pcie_bus);
 	if (ret) {
-		dev_err(pp->dev, "unable to enable pcie_ref_125m\n");
-		goto err_pcie_ref;
+		dev_err(pp->dev, "unable to enable pcie_bus clock\n");
+		goto err_pcie_bus;
 	}
 
-	ret = clk_prepare_enable(imx6_pcie->lvds_gate);
+	ret = clk_prepare_enable(imx6_pcie->pcie);
 	if (ret) {
-		dev_err(pp->dev, "unable to enable lvds_gate\n");
-		goto err_lvds_gate;
-	}
-
-	ret = clk_prepare_enable(imx6_pcie->pcie_axi);
-	if (ret) {
-		dev_err(pp->dev, "unable to enable pcie_axi\n");
-		goto err_pcie_axi;
+		dev_err(pp->dev, "unable to enable pcie clock\n");
+		goto err_pcie;
 	}
 
 	/* allow the clocks to stabilize */
@@ -274,13 +262,11 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
 	}
 	return 0;
 
-err_pcie_axi:
-	clk_disable_unprepare(imx6_pcie->lvds_gate);
-err_lvds_gate:
-	clk_disable_unprepare(imx6_pcie->pcie_ref_125m);
-err_pcie_ref:
-	clk_disable_unprepare(imx6_pcie->sata_ref_100m);
-err_sata_ref:
+err_pcie:
+	clk_disable_unprepare(imx6_pcie->pcie_bus);
+err_pcie_bus:
+	clk_disable_unprepare(imx6_pcie->pcie_phy);
+err_pcie_phy:
 	return ret;
 
 }
@@ -329,6 +315,13 @@ static int imx6_pcie_wait_for_link(struct pcie_port *pp)
 	return 0;
 }
 
+static irqreturn_t imx6_pcie_msi_handler(int irq, void *arg)
+{
+	struct pcie_port *pp = arg;
+
+	return dw_handle_msi_irq(pp);
+}
+
 static int imx6_pcie_start_link(struct pcie_port *pp)
 {
 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
@@ -403,6 +396,9 @@ static void imx6_pcie_host_init(struct pcie_port *pp)
 	dw_pcie_setup_rc(pp);
 
 	imx6_pcie_start_link(pp);
+
+	if (IS_ENABLED(CONFIG_PCI_MSI))
+		dw_pcie_msi_init(pp);
 }
 
 static void imx6_pcie_reset_phy(struct pcie_port *pp)
@@ -487,15 +483,25 @@ static struct pcie_host_ops imx6_pcie_host_ops = {
 	.host_init = imx6_pcie_host_init,
 };
 
-static int imx6_add_pcie_port(struct pcie_port *pp,
+static int __init imx6_add_pcie_port(struct pcie_port *pp,
 			struct platform_device *pdev)
 {
 	int ret;
 
-	pp->irq = platform_get_irq(pdev, 0);
-	if (!pp->irq) {
-		dev_err(&pdev->dev, "failed to get irq\n");
-		return -ENODEV;
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		pp->msi_irq = platform_get_irq_byname(pdev, "msi");
+		if (pp->msi_irq <= 0) {
+			dev_err(&pdev->dev, "failed to get MSI irq\n");
+			return -ENODEV;
+		}
+
+		ret = devm_request_irq(&pdev->dev, pp->msi_irq,
+		                       imx6_pcie_msi_handler,
+		                       IRQF_SHARED, "mx6-pcie-msi", pp);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to request MSI irq\n");
+			return -ENODEV;
+		}
 	}
 
 	pp->root_bus_nr = -1;
@@ -546,69 +552,26 @@ static int __init imx6_pcie_probe(struct platform_device *pdev)
 		}
 	}
 
-	imx6_pcie->power_on_gpio = of_get_named_gpio(np, "power-on-gpio", 0);
-	if (gpio_is_valid(imx6_pcie->power_on_gpio)) {
-		ret = devm_gpio_request_one(&pdev->dev,
-					imx6_pcie->power_on_gpio,
-					GPIOF_OUT_INIT_LOW,
-					"PCIe power enable");
-		if (ret) {
-			dev_err(&pdev->dev, "unable to get power-on gpio\n");
-			return ret;
-		}
-	}
-
-	imx6_pcie->wake_up_gpio = of_get_named_gpio(np, "wake-up-gpio", 0);
-	if (gpio_is_valid(imx6_pcie->wake_up_gpio)) {
-		ret = devm_gpio_request_one(&pdev->dev,
-					imx6_pcie->wake_up_gpio,
-					GPIOF_IN,
-					"PCIe wake up");
-		if (ret) {
-			dev_err(&pdev->dev, "unable to get wake-up gpio\n");
-			return ret;
-		}
-	}
-
-	imx6_pcie->disable_gpio = of_get_named_gpio(np, "disable-gpio", 0);
-	if (gpio_is_valid(imx6_pcie->disable_gpio)) {
-		ret = devm_gpio_request_one(&pdev->dev,
-					imx6_pcie->disable_gpio,
-					GPIOF_OUT_INIT_HIGH,
-					"PCIe disable endpoint");
-		if (ret) {
-			dev_err(&pdev->dev, "unable to get disable-ep gpio\n");
-			return ret;
-		}
-	}
-
 	/* Fetch clocks */
-	imx6_pcie->lvds_gate = devm_clk_get(&pdev->dev, "lvds_gate");
-	if (IS_ERR(imx6_pcie->lvds_gate)) {
+	imx6_pcie->pcie_phy = devm_clk_get(&pdev->dev, "pcie_phy");
+	if (IS_ERR(imx6_pcie->pcie_phy)) {
 		dev_err(&pdev->dev,
-			"lvds_gate clock select missing or invalid\n");
-		return PTR_ERR(imx6_pcie->lvds_gate);
+			"pcie_phy clock source missing or invalid\n");
+		return PTR_ERR(imx6_pcie->pcie_phy);
 	}
 
-	imx6_pcie->sata_ref_100m = devm_clk_get(&pdev->dev, "sata_ref_100m");
-	if (IS_ERR(imx6_pcie->sata_ref_100m)) {
+	imx6_pcie->pcie_bus = devm_clk_get(&pdev->dev, "pcie_bus");
+	if (IS_ERR(imx6_pcie->pcie_bus)) {
 		dev_err(&pdev->dev,
-			"sata_ref_100m clock source missing or invalid\n");
-		return PTR_ERR(imx6_pcie->sata_ref_100m);
+			"pcie_bus clock source missing or invalid\n");
+		return PTR_ERR(imx6_pcie->pcie_bus);
 	}
 
-	imx6_pcie->pcie_ref_125m = devm_clk_get(&pdev->dev, "pcie_ref_125m");
-	if (IS_ERR(imx6_pcie->pcie_ref_125m)) {
+	imx6_pcie->pcie = devm_clk_get(&pdev->dev, "pcie");
+	if (IS_ERR(imx6_pcie->pcie)) {
 		dev_err(&pdev->dev,
-			"pcie_ref_125m clock source missing or invalid\n");
-		return PTR_ERR(imx6_pcie->pcie_ref_125m);
-	}
-
-	imx6_pcie->pcie_axi = devm_clk_get(&pdev->dev, "pcie_axi");
-	if (IS_ERR(imx6_pcie->pcie_axi)) {
-		dev_err(&pdev->dev,
-			"pcie_axi clock source missing or invalid\n");
-		return PTR_ERR(imx6_pcie->pcie_axi);
+			"pcie clock source missing or invalid\n");
+		return PTR_ERR(imx6_pcie->pcie);
 	}
 
 	/* Grab GPR config register range */
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 509a29d84509..77a649dd1473 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -155,15 +155,17 @@ static struct irq_chip dw_msi_irq_chip = {
 };
 
 /* MSI int handler */
-void dw_handle_msi_irq(struct pcie_port *pp)
+irqreturn_t dw_handle_msi_irq(struct pcie_port *pp)
 {
 	unsigned long val;
 	int i, pos, irq;
+	irqreturn_t ret = IRQ_NONE;
 
 	for (i = 0; i < MAX_MSI_CTRLS; i++) {
 		dw_pcie_rd_own_conf(pp, PCIE_MSI_INTR0_STATUS + i * 12, 4,
 				(u32 *)&val);
 		if (val) {
+			ret = IRQ_HANDLED;
 			pos = 0;
 			while ((pos = find_next_bit(&val, 32, pos)) != 32) {
 				irq = irq_find_mapping(pp->irq_domain,
@@ -176,6 +178,8 @@ void dw_handle_msi_irq(struct pcie_port *pp)
 			}
 		}
 	}
+
+	return ret;
 }
 
 void dw_pcie_msi_init(struct pcie_port *pp)
diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h
index 3063b3594d88..a169d22d517e 100644
--- a/drivers/pci/host/pcie-designware.h
+++ b/drivers/pci/host/pcie-designware.h
@@ -68,7 +68,7 @@ struct pcie_host_ops {
 
 int dw_pcie_cfg_read(void __iomem *addr, int where, int size, u32 *val);
 int dw_pcie_cfg_write(void __iomem *addr, int where, int size, u32 val);
-void dw_handle_msi_irq(struct pcie_port *pp);
+irqreturn_t dw_handle_msi_irq(struct pcie_port *pp);
 void dw_pcie_msi_init(struct pcie_port *pp);
 int dw_pcie_link_up(struct pcie_port *pp);
 void dw_pcie_setup_rc(struct pcie_port *pp);
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index de7a74782f92..cb6f24740ee3 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -106,7 +106,7 @@ static int virtfn_add(struct pci_dev *dev, int id, int reset)
 	pci_device_add(virtfn, virtfn->bus);
 	mutex_unlock(&iov->dev->sriov->lock);
 
-	rc = pci_bus_add_device(virtfn);
+	pci_bus_add_device(virtfn);
 	sprintf(buf, "virtfn%u", id);
 	rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);
 	if (rc)
diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index c5e082fb82fa..91ef69a52263 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -642,8 +642,7 @@ static void asus_rfkill_hotplug(struct asus_wmi *asus)
 			dev = pci_scan_single_device(bus, 0);
 			if (dev) {
 				pci_bus_assign_resources(bus);
-				if (pci_bus_add_device(dev))
-					pr_err("Unable to hotplug wifi\n");
+				pci_bus_add_device(dev);
 			}
 		} else {
 			dev = pci_get_slot(bus, 0);
diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index 399e8c562192..9b0c57cd1d4a 100644
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -633,8 +633,7 @@ static void eeepc_rfkill_hotplug(struct eeepc_laptop *eeepc, acpi_handle handle)
 			dev = pci_scan_single_device(bus, 0);
 			if (dev) {
 				pci_bus_assign_resources(bus);
-				if (pci_bus_add_device(dev))
-					pr_err("Unable to hotplug wifi\n");
+				pci_bus_add_device(dev);
 			}
 		} else {
 			dev = pci_get_slot(bus, 0);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 65f22e85612d..71d9673c1b2c 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -781,7 +781,7 @@ int pci_scan_slot(struct pci_bus *bus, int devfn);
 struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn);
 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus);
 unsigned int pci_scan_child_bus(struct pci_bus *bus);
-int __must_check pci_bus_add_device(struct pci_dev *dev);
+void pci_bus_add_device(struct pci_dev *dev);
 void pci_read_bridge_bases(struct pci_bus *child);
 struct resource *pci_find_parent_resource(const struct pci_dev *dev,
 					  struct resource *res);