Merge tag 'pci-v3.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for the v3.14 merge window:

  Resource management
    - Change pci_bus_region addresses to dma_addr_t (Bjorn Helgaas)
    - Support 64-bit AGP BARs (Bjorn Helgaas, Yinghai Lu)
    - Add pci_bus_address() to get bus address of a BAR (Bjorn Helgaas)
    - Use pci_resource_start() for CPU address of AGP BARs (Bjorn Helgaas)
    - Enforce bus address limits in resource allocation (Yinghai Lu)
    - Allocate 64-bit BARs above 4G when possible (Yinghai Lu)
    - Convert pcibios_resource_to_bus() to take pci_bus, not pci_dev (Yinghai Lu)

  PCI device hotplug
    - Major rescan/remove locking update (Rafael J. Wysocki)
    - Make ioapic builtin only (not modular) (Yinghai Lu)
    - Fix release/free issues (Yinghai Lu)
    - Clean up pciehp (Bjorn Helgaas)
    - Announce pciehp slot info during enumeration (Bjorn Helgaas)

  MSI
    - Add pci_msi_vec_count(), pci_msix_vec_count() (Alexander Gordeev)
    - Add pci_enable_msi_range(), pci_enable_msix_range() (Alexander Gordeev)
    - Deprecate "tri-state" interfaces: fail/success/fail+info (Alexander Gordeev)
    - Export MSI mode using attributes, not kobjects (Greg Kroah-Hartman)
    - Drop "irq" param from *_restore_msi_irqs() (DuanZhenzhong)

  SR-IOV
    - Clear NumVFs when disabling SR-IOV in sriov_init() (ethan.zhao)

  Virtualization
    - Add support for save/restore of extended capabilities (Alex Williamson)
    - Add Virtual Channel to save/restore support (Alex Williamson)
    - Never treat a VF as a multifunction device (Alex Williamson)
    - Add pci_try_reset_function(), et al (Alex Williamson)

  AER
    - Ignore non-PCIe error sources (Betty Dall)
    - Support ACPI HEST error sources for domains other than 0 (Betty Dall)
    - Consolidate HEST error source parsers (Bjorn Helgaas)
    - Add a TLP header print helper (Borislav Petkov)

  Freescale i.MX6
    - Remove unnecessary code (Fabio Estevam)
    - Make reset-gpio optional (Marek Vasut)
    - Report "link up" only after link training completes (Marek Vasut)
    - Start link in Gen1 before negotiating for Gen2 mode (Marek Vasut)
    - Fix PCIe startup code (Richard Zhu)

  Marvell MVEBU
    - Remove duplicate of_clk_get_by_name() call (Andrew Lunn)
    - Drop writes to bridge Secondary Status register (Jason Gunthorpe)
    - Obey bridge PCI_COMMAND_MEM and PCI_COMMAND_IO bits (Jason Gunthorpe)
    - Support a bridge with no IO port window (Jason Gunthorpe)
    - Use max_t() instead of max(resource_size_t,) (Jingoo Han)
    - Remove redundant of_match_ptr (Sachin Kamat)
    - Call pci_ioremap_io() at startup instead of dynamically (Thomas Petazzoni)

  NVIDIA Tegra
    - Disable Gen2 for Tegra20 and Tegra30 (Eric Brower)

  Renesas R-Car
    - Add runtime PM support (Valentine Barshak)
    - Fix rcar_pci_probe() return value check (Wei Yongjun)

  Synopsys DesignWare
    - Fix crash in dw_msi_teardown_irq() (Bjørn Erik Nilsen)
    - Remove redundant call to pci_write_config_word() (Bjørn Erik Nilsen)
    - Fix missing MSI IRQs (Harro Haan)
    - Add dw_pcie prefix before cfg_read/write (Pratyush Anand)
    - Fix I/O transfers by using CPU (not realio) address (Pratyush Anand)
    - Whitespace cleanup (Jingoo Han)

  EISA
    - Call put_device() if device_register() fails (Levente Kurusa)
    - Revert EISA initialization breakage ((Bjorn Helgaas)

  Miscellaneous
    - Remove unused code, including PCIe 3.0 interfaces (Stephen Hemminger)
    - Prevent bus conflicts while checking for bridge apertures (Bjorn Helgaas)
    - Stop clearing bridge Secondary Status when setting up I/O aperture (Bjorn Helgaas)
    - Use dev_is_pci() to identify PCI devices (Yijing Wang)
    - Deprecate DEFINE_PCI_DEVICE_TABLE (Joe Perches)
    - Update documentation 00-INDEX (Erik Ekman)"

* tag 'pci-v3.14-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (119 commits)
  Revert "EISA: Initialize device before its resources"
  Revert "EISA: Log device resources in dmesg"
  vfio-pci: Use pci "try" reset interface
  PCI: Check parent kobject in pci_destroy_dev()
  xen/pcifront: Use global PCI rescan-remove locking
  powerpc/eeh: Use global PCI rescan-remove locking
  PCI: Fix pci_check_and_unmask_intx() comment typos
  PCI: Add pci_try_reset_function(), pci_try_reset_slot(), pci_try_reset_bus()
  MPT / PCI: Use pci_stop_and_remove_bus_device_locked()
  platform / x86: Use global PCI rescan-remove locking
  PCI: hotplug: Use global PCI rescan-remove locking
  pcmcia: Use global PCI rescan-remove locking
  ACPI / hotplug / PCI: Use global PCI rescan-remove locking
  ACPI / PCI: Use global PCI rescan-remove locking in PCI root hotplug
  PCI: Add global pci_lock_rescan_remove()
  PCI: Cleanup pci.h whitespace
  PCI: Reorder so actual code comes before stubs
  PCI/AER: Support ACPI HEST AER error sources for PCI domains other than 0
  ACPICA: Add helper macros to extract bus/segment numbers from HEST table.
  PCI: Make local functions static
  ...

50 files changed, 1894 insertions, 1363 deletions

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index b6a99f7a9b20..893503fa1782 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -105,9 +105,10 @@ config PCI_PASID
 	  If unsure, say N.
 
 config PCI_IOAPIC
-	tristate "PCI IO-APIC hotplug support" if X86
+	bool "PCI IO-APIC hotplug support" if X86
 	depends on PCI
 	depends on ACPI
+	depends on X86_IO_APIC
 	default !X86
 
 config PCI_LABEL
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 6ebf5bf8e7a7..17d2b07ee67c 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -4,7 +4,7 @@
 
 obj-y		+= access.o bus.o probe.o host-bridge.o remove.o pci.o \
 			pci-driver.o search.o pci-sysfs.o rom.o setup-res.o \
-			irq.o vpd.o setup-bus.o
+			irq.o vpd.o setup-bus.o vc.o
 obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_SYSFS) += slot.o
 
diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 0857ca981fae..7f8b78c08879 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -381,30 +381,6 @@ int pci_vpd_pci22_init(struct pci_dev *dev)
 }
 
 /**
- * pci_vpd_truncate - Set available Vital Product Data size
- * @dev:	pci device struct
- * @size:	available memory in bytes
- *
- * Adjust size of available VPD area.
- */
-int pci_vpd_truncate(struct pci_dev *dev, size_t size)
-{
-	if (!dev->vpd)
-		return -EINVAL;
-
-	/* limited by the access method */
-	if (size > dev->vpd->len)
-		return -EINVAL;
-
-	dev->vpd->len = size;
-	if (dev->vpd->attr)
-		dev->vpd->attr->size = size;
-
-	return 0;
-}
-EXPORT_SYMBOL(pci_vpd_truncate);
-
-/**
  * pci_cfg_access_lock - Lock PCI config reads/writes
  * @dev:	pci device struct
  *
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index e52d7ffa38b9..a8099d4d0c9d 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -235,27 +235,6 @@ void pci_disable_pri(struct pci_dev *pdev)
 EXPORT_SYMBOL_GPL(pci_disable_pri);
 
 /**
- * pci_pri_enabled - Checks if PRI capability is enabled
- * @pdev: PCI device structure
- *
- * Returns true if PRI is enabled on the device, false otherwise
- */
-bool pci_pri_enabled(struct pci_dev *pdev)
-{
-	u16 control;
-	int pos;
-
-	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
-	if (!pos)
-		return false;
-
-	pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
-
-	return (control & PCI_PRI_CTRL_ENABLE) ? true : false;
-}
-EXPORT_SYMBOL_GPL(pci_pri_enabled);
-
-/**
  * pci_reset_pri - Resets device's PRI state
  * @pdev: PCI device structure
  *
@@ -282,67 +261,6 @@ int pci_reset_pri(struct pci_dev *pdev)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(pci_reset_pri);
-
-/**
- * pci_pri_stopped - Checks whether the PRI capability is stopped
- * @pdev: PCI device structure
- *
- * Returns true if the PRI capability on the device is disabled and the
- * device has no outstanding PRI requests, false otherwise. The device
- * indicates this via the STOPPED bit in the status register of the
- * capability.
- * The device internal state can be cleared by resetting the PRI state
- * with pci_reset_pri(). This can force the capability into the STOPPED
- * state.
- */
-bool pci_pri_stopped(struct pci_dev *pdev)
-{
-	u16 control, status;
-	int pos;
-
-	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
-	if (!pos)
-		return true;
-
-	pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
-	pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status);
-
-	if (control & PCI_PRI_CTRL_ENABLE)
-		return false;
-
-	return (status & PCI_PRI_STATUS_STOPPED) ? true : false;
-}
-EXPORT_SYMBOL_GPL(pci_pri_stopped);
-
-/**
- * pci_pri_status - Request PRI status of a device
- * @pdev: PCI device structure
- *
- * Returns negative value on failure, status on success. The status can
- * be checked against status-bits. Supported bits are currently:
- * PCI_PRI_STATUS_RF:      Response failure
- * PCI_PRI_STATUS_UPRGI:   Unexpected Page Request Group Index
- * PCI_PRI_STATUS_STOPPED: PRI has stopped
- */
-int pci_pri_status(struct pci_dev *pdev)
-{
-	u16 status, control;
-	int pos;
-
-	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
-	if (!pos)
-		return -EINVAL;
-
-	pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
-	pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status);
-
-	/* Stopped bit is undefined when enable == 1, so clear it */
-	if (control & PCI_PRI_CTRL_ENABLE)
-		status &= ~PCI_PRI_STATUS_STOPPED;
-
-	return status;
-}
-EXPORT_SYMBOL_GPL(pci_pri_status);
 #endif /* CONFIG_PCI_PRI */
 
 #ifdef CONFIG_PCI_PASID
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index fc1b74013743..00660cc502c5 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -98,41 +98,54 @@ void pci_bus_remove_resources(struct pci_bus *bus)
 	}
 }
 
-/**
- * pci_bus_alloc_resource - allocate a resource from a parent bus
- * @bus: PCI bus
- * @res: resource to allocate
- * @size: size of resource to allocate
- * @align: alignment of resource to allocate
- * @min: minimum /proc/iomem address to allocate
- * @type_mask: IORESOURCE_* type flags
- * @alignf: resource alignment function
- * @alignf_data: data argument for resource alignment function
- *
- * Given the PCI bus a device resides on, the size, minimum address,
- * alignment and type, try to find an acceptable resource allocation
- * for a specific device resource.
+static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+static struct pci_bus_region pci_64_bit = {0,
+				(dma_addr_t) 0xffffffffffffffffULL};
+static struct pci_bus_region pci_high = {(dma_addr_t) 0x100000000ULL,
+				(dma_addr_t) 0xffffffffffffffffULL};
+#endif
+
+/*
+ * @res contains CPU addresses.  Clip it so the corresponding bus addresses
+ * on @bus are entirely within @region.  This is used to control the bus
+ * addresses of resources we allocate, e.g., we may need a resource that
+ * can be mapped by a 32-bit BAR.
  */
-int
-pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
+static void pci_clip_resource_to_region(struct pci_bus *bus,
+					struct resource *res,
+					struct pci_bus_region *region)
+{
+	struct pci_bus_region r;
+
+	pcibios_resource_to_bus(bus, &r, res);
+	if (r.start < region->start)
+		r.start = region->start;
+	if (r.end > region->end)
+		r.end = region->end;
+
+	if (r.end < r.start)
+		res->end = res->start - 1;
+	else
+		pcibios_bus_to_resource(bus, res, &r);
+}
+
+static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
 		resource_size_t size, resource_size_t align,
 		resource_size_t min, unsigned int type_mask,
 		resource_size_t (*alignf)(void *,
 					  const struct resource *,
 					  resource_size_t,
 					  resource_size_t),
-		void *alignf_data)
+		void *alignf_data,
+		struct pci_bus_region *region)
 {
-	int i, ret = -ENOMEM;
-	struct resource *r;
-	resource_size_t max = -1;
+	int i, ret;
+	struct resource *r, avail;
+	resource_size_t max;
 
 	type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
 
-	/* don't allocate too high if the pref mem doesn't support 64bit*/
-	if (!(res->flags & IORESOURCE_MEM_64))
-		max = PCIBIOS_MAX_MEM_32;
-
 	pci_bus_for_each_resource(bus, r, i) {
 		if (!r)
 			continue;
@@ -147,15 +160,74 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
 		    !(res->flags & IORESOURCE_PREFETCH))
 			continue;
 
+		avail = *r;
+		pci_clip_resource_to_region(bus, &avail, region);
+		if (!resource_size(&avail))
+			continue;
+
+		/*
+		 * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
+		 * protect badly documented motherboard resources, but if
+		 * this is an already-configured bridge window, its start
+		 * overrides "min".
+		 */
+		if (avail.start)
+			min = avail.start;
+
+		max = avail.end;
+
 		/* Ok, try it out.. */
-		ret = allocate_resource(r, res, size,
-					r->start ? : min,
-					max, align,
-					alignf, alignf_data);
+		ret = allocate_resource(r, res, size, min, max,
+					align, alignf, alignf_data);
 		if (ret == 0)
-			break;
+			return 0;
 	}
-	return ret;
+	return -ENOMEM;
+}
+
+/**
+ * pci_bus_alloc_resource - allocate a resource from a parent bus
+ * @bus: PCI bus
+ * @res: resource to allocate
+ * @size: size of resource to allocate
+ * @align: alignment of resource to allocate
+ * @min: minimum /proc/iomem address to allocate
+ * @type_mask: IORESOURCE_* type flags
+ * @alignf: resource alignment function
+ * @alignf_data: data argument for resource alignment function
+ *
+ * Given the PCI bus a device resides on, the size, minimum address,
+ * alignment and type, try to find an acceptable resource allocation
+ * for a specific device resource.
+ */
+int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
+		resource_size_t size, resource_size_t align,
+		resource_size_t min, unsigned int type_mask,
+		resource_size_t (*alignf)(void *,
+					  const struct resource *,
+					  resource_size_t,
+					  resource_size_t),
+		void *alignf_data)
+{
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+	int rc;
+
+	if (res->flags & IORESOURCE_MEM_64) {
+		rc = pci_bus_alloc_from_region(bus, res, size, align, min,
+					       type_mask, alignf, alignf_data,
+					       &pci_high);
+		if (rc == 0)
+			return 0;
+
+		return pci_bus_alloc_from_region(bus, res, size, align, min,
+						 type_mask, alignf, alignf_data,
+						 &pci_64_bit);
+	}
+#endif
+
+	return pci_bus_alloc_from_region(bus, res, size, align, min,
+					 type_mask, alignf, alignf_data,
+					 &pci_32_bit);
 }
 
 void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
@@ -176,6 +248,7 @@ int pci_bus_add_device(struct pci_dev *dev)
 	 */
 	pci_fixup_device(pci_fixup_final, dev);
 	pci_create_sysfs_dev_files(dev);
+	pci_proc_attach_device(dev);
 
 	dev->match_driver = true;
 	retval = device_attach(&dev->dev);
diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c
index a68dc613a5be..06ace6248c61 100644
--- a/drivers/pci/host-bridge.c
+++ b/drivers/pci/host-bridge.c
@@ -9,22 +9,19 @@
 
 #include "pci.h"
 
-static struct pci_bus *find_pci_root_bus(struct pci_dev *dev)
+static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
 {
-	struct pci_bus *bus;
-
-	bus = dev->bus;
 	while (bus->parent)
 		bus = bus->parent;
 
 	return bus;
 }
 
-static struct pci_host_bridge *find_pci_host_bridge(struct pci_dev *dev)
+static struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus)
 {
-	struct pci_bus *bus = find_pci_root_bus(dev);
+	struct pci_bus *root_bus = find_pci_root_bus(bus);
 
-	return to_pci_host_bridge(bus->bridge);
+	return to_pci_host_bridge(root_bus->bridge);
 }
 
 void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
@@ -40,10 +37,10 @@ static bool resource_contains(struct resource *res1, struct resource *res2)
 	return res1->start <= res2->start && res1->end >= res2->end;
 }
 
-void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
+void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
 			     struct resource *res)
 {
-	struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
+	struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
 	struct pci_host_bridge_window *window;
 	resource_size_t offset = 0;
 
@@ -68,10 +65,10 @@ static bool region_contains(struct pci_bus_region *region1,
 	return region1->start <= region2->start && region1->end >= region2->end;
 }
 
-void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
+void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
 			     struct pci_bus_region *region)
 {
-	struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
+	struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
 	struct pci_host_bridge_window *window;
 	resource_size_t offset = 0;
 
diff --git a/drivers/pci/host/pci-exynos.c b/drivers/pci/host/pci-exynos.c
index 24beed38ddc7..3de6bfbbe8e9 100644
--- a/drivers/pci/host/pci-exynos.c
+++ b/drivers/pci/host/pci-exynos.c
@@ -468,7 +468,7 @@ static int exynos_pcie_rd_own_conf(struct pcie_port *pp, int where, int size,
 	int ret;
 
 	exynos_pcie_sideband_dbi_r_mode(pp, true);
-	ret = cfg_read(pp->dbi_base + (where & ~0x3), where, size, val);
+	ret = dw_pcie_cfg_read(pp->dbi_base + (where & ~0x3), where, size, val);
 	exynos_pcie_sideband_dbi_r_mode(pp, false);
 	return ret;
 }
@@ -479,7 +479,8 @@ static int exynos_pcie_wr_own_conf(struct pcie_port *pp, int where, int size,
 	int ret;
 
 	exynos_pcie_sideband_dbi_w_mode(pp, true);
-	ret = cfg_write(pp->dbi_base + (where & ~0x3), where, size, val);
+	ret = dw_pcie_cfg_write(pp->dbi_base + (where & ~0x3),
+			where, size, val);
 	exynos_pcie_sideband_dbi_w_mode(pp, false);
 	return ret;
 }
diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
index bd70af8f31ac..e8663a8c3406 100644
--- a/drivers/pci/host/pci-imx6.c
+++ b/drivers/pci/host/pci-imx6.c
@@ -44,10 +44,18 @@ struct imx6_pcie {
 	void __iomem		*mem_base;
 };
 
+/* PCIe Root Complex registers (memory-mapped) */
+#define PCIE_RC_LCR				0x7c
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1	0x1
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2	0x2
+#define PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK	0xf
+
 /* PCIe Port Logic registers (memory-mapped) */
 #define PL_OFFSET 0x700
 #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
 #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
+#define PCIE_PHY_DEBUG_R1_XMLH_LINK_IN_TRAINING	(1 << 29)
+#define PCIE_PHY_DEBUG_R1_XMLH_LINK_UP		(1 << 4)
 
 #define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
 #define PCIE_PHY_CTRL_DATA_LOC 0
@@ -59,6 +67,9 @@ struct imx6_pcie {
 #define PCIE_PHY_STAT (PL_OFFSET + 0x110)
 #define PCIE_PHY_STAT_ACK_LOC 16
 
+#define PCIE_LINK_WIDTH_SPEED_CONTROL	0x80C
+#define PORT_LOGIC_SPEED_CHANGE		(0x1 << 17)
+
 /* PHY registers (not memory-mapped) */
 #define PCIE_PHY_RX_ASIC_OUT 0x100D
 
@@ -209,15 +220,9 @@ static int imx6_pcie_assert_core_reset(struct pcie_port *pp)
 
 	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
 			IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
-	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
-			IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
 	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
 			IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
 
-	gpio_set_value(imx6_pcie->reset_gpio, 0);
-	msleep(100);
-	gpio_set_value(imx6_pcie->reset_gpio, 1);
-
 	return 0;
 }
 
@@ -261,6 +266,12 @@ static int imx6_pcie_deassert_core_reset(struct pcie_port *pp)
 	/* allow the clocks to stabilize */
 	usleep_range(200, 500);
 
+	/* Some boards don't have PCIe reset GPIO. */
+	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
+		gpio_set_value(imx6_pcie->reset_gpio, 0);
+		msleep(100);
+		gpio_set_value(imx6_pcie->reset_gpio, 1);
+	}
 	return 0;
 
 err_pcie_axi:
@@ -299,11 +310,90 @@ static void imx6_pcie_init_phy(struct pcie_port *pp)
 			IMX6Q_GPR8_TX_SWING_LOW, 127 << 25);
 }
 
-static void imx6_pcie_host_init(struct pcie_port *pp)
+static int imx6_pcie_wait_for_link(struct pcie_port *pp)
+{
+	int count = 200;
+
+	while (!dw_pcie_link_up(pp)) {
+		usleep_range(100, 1000);
+		if (--count)
+			continue;
+
+		dev_err(pp->dev, "phy link never came up\n");
+		dev_dbg(pp->dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
+			readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
+			readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int imx6_pcie_start_link(struct pcie_port *pp)
 {
-	int count = 0;
 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pp);
+	uint32_t tmp;
+	int ret, count;
 
+	/*
+	 * Force Gen1 operation when starting the link.  In case the link is
+	 * started in Gen2 mode, there is a possibility the devices on the
+	 * bus will not be detected at all.  This happens with PCIe switches.
+	 */
+	tmp = readl(pp->dbi_base + PCIE_RC_LCR);
+	tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+	tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1;
+	writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+
+	/* Start LTSSM. */
+	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
+			IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
+
+	ret = imx6_pcie_wait_for_link(pp);
+	if (ret)
+		return ret;
+
+	/* Allow Gen2 mode after the link is up. */
+	tmp = readl(pp->dbi_base + PCIE_RC_LCR);
+	tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
+	tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
+	writel(tmp, pp->dbi_base + PCIE_RC_LCR);
+
+	/*
+	 * Start Directed Speed Change so the best possible speed both link
+	 * partners support can be negotiated.
+	 */
+	tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+	tmp |= PORT_LOGIC_SPEED_CHANGE;
+	writel(tmp, pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+
+	count = 200;
+	while (count--) {
+		tmp = readl(pp->dbi_base + PCIE_LINK_WIDTH_SPEED_CONTROL);
+		/* Test if the speed change finished. */
+		if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
+			break;
+		usleep_range(100, 1000);
+	}
+
+	/* Make sure link training is finished as well! */
+	if (count)
+		ret = imx6_pcie_wait_for_link(pp);
+	else
+		ret = -EINVAL;
+
+	if (ret) {
+		dev_err(pp->dev, "Failed to bring link up!\n");
+	} else {
+		tmp = readl(pp->dbi_base + 0x80);
+		dev_dbg(pp->dev, "Link up, Gen=%i\n", (tmp >> 16) & 0xf);
+	}
+
+	return ret;
+}
+
+static void imx6_pcie_host_init(struct pcie_port *pp)
+{
 	imx6_pcie_assert_core_reset(pp);
 
 	imx6_pcie_init_phy(pp);
@@ -312,33 +402,41 @@ static void imx6_pcie_host_init(struct pcie_port *pp)
 
 	dw_pcie_setup_rc(pp);
 
-	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
-			IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
+	imx6_pcie_start_link(pp);
+}
 
-	while (!dw_pcie_link_up(pp)) {
-		usleep_range(100, 1000);
-		count++;
-		if (count >= 200) {
-			dev_err(pp->dev, "phy link never came up\n");
-			dev_dbg(pp->dev,
-				"DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
-				readl(pp->dbi_base + PCIE_PHY_DEBUG_R0),
-				readl(pp->dbi_base + PCIE_PHY_DEBUG_R1));
-			break;
-		}
-	}
+static void imx6_pcie_reset_phy(struct pcie_port *pp)
+{
+	uint32_t temp;
+
+	pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
+	temp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+		 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+	pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
+
+	usleep_range(2000, 3000);
 
-	return;
+	pcie_phy_read(pp->dbi_base, PHY_RX_OVRD_IN_LO, &temp);
+	temp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
+		  PHY_RX_OVRD_IN_LO_RX_PLL_EN);
+	pcie_phy_write(pp->dbi_base, PHY_RX_OVRD_IN_LO, temp);
 }
 
 static int imx6_pcie_link_up(struct pcie_port *pp)
 {
-	u32 rc, ltssm, rx_valid, temp;
+	u32 rc, ltssm, rx_valid;
 
-	/* link is debug bit 36, debug register 1 starts at bit 32 */
-	rc = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1) & (0x1 << (36 - 32));
-	if (rc)
-		return -EAGAIN;
+	/*
+	 * Test if the PHY reports that the link is up and also