diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h
index 174170f14f069f94931a8bb0dfaee96a61efd366..7a47498b0aac0d732e3ca2c3c5d774c395adc336 100644
--- a/drivers/usb/core/hcd.h
+++ b/drivers/usb/core/hcd.h
@@ -173,6 +173,7 @@ struct hc_driver {
 #define	HCD_LOCAL_MEM	0x0002		/* HC needs local memory */
 #define	HCD_USB11	0x0010		/* USB 1.1 */
 #define	HCD_USB2	0x0020		/* USB 2.0 */
+#define	HCD_USB3	0x0040		/* USB 3.0 */
 
 	/* called to init HCD and root hub */
 	int	(*reset) (struct usb_hcd *hcd);
diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 033c2846ce5923e05f0805bff889ab45268ea056..83b5f9cea85ac9f43af8d3b1eb87a259517cc05c 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -15,6 +15,7 @@
 #include <linux/delay.h>
 #include <linux/acpi.h>
 #include "pci-quirks.h"
+#include "xhci-ext-caps.h"
 
 
 #define UHCI_USBLEGSUP		0xc0		/* legacy support */
@@ -341,7 +342,127 @@ static void __devinit quirk_usb_disable_ehci(struct pci_dev *pdev)
 	return;
 }
 
+/*
+ * handshake - spin reading a register until handshake completes
+ * @ptr: address of hc register to be read
+ * @mask: bits to look at in result of read
+ * @done: value of those bits when handshake succeeds
+ * @wait_usec: timeout in microseconds
+ * @delay_usec: delay in microseconds to wait between polling
+ *
+ * Polls a register every delay_usec microseconds.
+ * Returns 0 when the mask bits have the value done.
+ * Returns -ETIMEDOUT if this condition is not true after
+ * wait_usec microseconds have passed.
+ */
+static int handshake(void __iomem *ptr, u32 mask, u32 done,
+		int wait_usec, int delay_usec)
+{
+	u32	result;
+
+	do {
+		result = readl(ptr);
+		result &= mask;
+		if (result == done)
+			return 0;
+		udelay(delay_usec);
+		wait_usec -= delay_usec;
+	} while (wait_usec > 0);
+	return -ETIMEDOUT;
+}
+
+/**
+ * PCI Quirks for xHCI.
+ *
+ * Takes care of the handoff between the Pre-OS (i.e. BIOS) and the OS.
+ * It signals to the BIOS that the OS wants control of the host controller,
+ * and then waits 5 seconds for the BIOS to hand over control.
+ * If we timeout, assume the BIOS is broken and take control anyway.
+ */
+static void __devinit quirk_usb_handoff_xhci(struct pci_dev *pdev)
+{
+	void __iomem *base;
+	int ext_cap_offset;
+	void __iomem *op_reg_base;
+	u32 val;
+	int timeout;
+
+	if (!mmio_resource_enabled(pdev, 0))
+		return;
+
+	base = ioremap_nocache(pci_resource_start(pdev, 0),
+				pci_resource_len(pdev, 0));
+	if (base == NULL)
+		return;
 
+	/*
+	 * Find the Legacy Support Capability register -
+	 * this is optional for xHCI host controllers.
+	 */
+	ext_cap_offset = xhci_find_next_cap_offset(base, XHCI_HCC_PARAMS_OFFSET);
+	do {
+		if (!ext_cap_offset)
+			/* We've reached the end of the extended capabilities */
+			goto hc_init;
+		val = readl(base + ext_cap_offset);
+		if (XHCI_EXT_CAPS_ID(val) == XHCI_EXT_CAPS_LEGACY)
+			break;
+		ext_cap_offset = xhci_find_next_cap_offset(base, ext_cap_offset);
+	} while (1);
+
+	/* If the BIOS owns the HC, signal that the OS wants it, and wait */
+	if (val & XHCI_HC_BIOS_OWNED) {
+		writel(val & XHCI_HC_OS_OWNED, base + ext_cap_offset);
+
+		/* Wait for 5 seconds with 10 microsecond polling interval */
+		timeout = handshake(base + ext_cap_offset, XHCI_HC_BIOS_OWNED,
+				0, 5000, 10);
+
+		/* Assume a buggy BIOS and take HC ownership anyway */
+		if (timeout) {
+			dev_warn(&pdev->dev, "xHCI BIOS handoff failed"
+					" (BIOS bug ?) %08x\n", val);
+			writel(val & ~XHCI_HC_BIOS_OWNED, base + ext_cap_offset);
+		}
+	}
+
+	/* Disable any BIOS SMIs */
+	writel(XHCI_LEGACY_DISABLE_SMI,
+			base + ext_cap_offset + XHCI_LEGACY_CONTROL_OFFSET);
+
+hc_init:
+	op_reg_base = base + XHCI_HC_LENGTH(readl(base));
+
+	/* Wait for the host controller to be ready before writing any
+	 * operational or runtime registers.  Wait 5 seconds and no more.
+	 */
+	timeout = handshake(op_reg_base + XHCI_STS_OFFSET, XHCI_STS_CNR, 0,
+			5000, 10);
+	/* Assume a buggy HC and start HC initialization anyway */
+	if (timeout) {
+		val = readl(op_reg_base + XHCI_STS_OFFSET);
+		dev_warn(&pdev->dev,
+				"xHCI HW not ready after 5 sec (HC bug?) "
+				"status = 0x%x\n", val);
+	}
+
+	/* Send the halt and disable interrupts command */
+	val = readl(op_reg_base + XHCI_CMD_OFFSET);
+	val &= ~(XHCI_CMD_RUN | XHCI_IRQS);
+	writel(val, op_reg_base + XHCI_CMD_OFFSET);
+
+	/* Wait for the HC to halt - poll every 125 usec (one microframe). */
+	timeout = handshake(op_reg_base + XHCI_STS_OFFSET, XHCI_STS_HALT, 1,
+			XHCI_MAX_HALT_USEC, 125);
+	if (timeout) {
+		val = readl(op_reg_base + XHCI_STS_OFFSET);
+		dev_warn(&pdev->dev,
+				"xHCI HW did not halt within %d usec "
+				"status = 0x%x\n", XHCI_MAX_HALT_USEC, val);
+	}
+
+	iounmap(base);
+}
 
 static void __devinit quirk_usb_early_handoff(struct pci_dev *pdev)
 {
@@ -351,5 +472,7 @@ static void __devinit quirk_usb_early_handoff(struct pci_dev *pdev)
 		quirk_usb_handoff_ohci(pdev);
 	else if (pdev->class == PCI_CLASS_SERIAL_USB_EHCI)
 		quirk_usb_disable_ehci(pdev);
+	else if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI)
+		quirk_usb_handoff_xhci(pdev);
 }
 DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_usb_early_handoff);
diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c
new file mode 100644
index 0000000000000000000000000000000000000000..64fcc22e9d59a44c34c2198724455b236c6a9e9e
--- /dev/null
+++ b/drivers/usb/host/xhci-hcd.c
@@ -0,0 +1,377 @@
+/*
+ * xHCI host controller driver
+ *
+ * Copyright (C) 2008 Intel Corp.
+ *
+ * Author: Sarah Sharp
+ * Some code borrowed from the Linux EHCI driver.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+
+#include "xhci.h"
+
+#define DRIVER_AUTHOR "Sarah Sharp"
+#define DRIVER_DESC "'eXtensible' Host Controller (xHC) Driver"
+
+/* TODO: copied from ehci-hcd.c - can this be refactored? */
+/*
+ * handshake - spin reading hc until handshake completes or fails
+ * @ptr: address of hc register to be read
+ * @mask: bits to look at in result of read
+ * @done: value of those bits when handshake succeeds
+ * @usec: timeout in microseconds
+ *
+ * Returns negative errno, or zero on success
+ *
+ * Success happens when the "mask" bits have the specified value (hardware
+ * handshake done).  There are two failure modes:  "usec" have passed (major
+ * hardware flakeout), or the register reads as all-ones (hardware removed).
+ */
+static int handshake(struct xhci_hcd *xhci, void __iomem *ptr,
+		      u32 mask, u32 done, int usec)
+{
+	u32	result;
+
+	do {
+		result = xhci_readl(xhci, ptr);
+		if (result == ~(u32)0)		/* card removed */
+			return -ENODEV;
+		result &= mask;
+		if (result == done)
+			return 0;
+		udelay(1);
+		usec--;
+	} while (usec > 0);
+	return -ETIMEDOUT;
+}
+
+/*
+ * Force HC into halt state.
+ *
+ * Disable any IRQs and clear the run/stop bit.
+ * HC will complete any current and actively pipelined transactions, and
+ * should halt within 16 microframes of the run/stop bit being cleared.
+ * Read HC Halted bit in the status register to see when the HC is finished.
+ * XXX: shouldn't we set HC_STATE_HALT here somewhere?
+ */
+int xhci_halt(struct xhci_hcd *xhci)
+{
+	u32 halted;
+	u32 cmd;
+	u32 mask;
+
+	xhci_dbg(xhci, "// Halt the HC\n");
+	/* Disable all interrupts from the host controller */
+	mask = ~(XHCI_IRQS);
+	halted = xhci_readl(xhci, &xhci->op_regs->status) & STS_HALT;
+	if (!halted)
+		mask &= ~CMD_RUN;
+
+	cmd = xhci_readl(xhci, &xhci->op_regs->command);
+	cmd &= mask;
+	xhci_writel(xhci, cmd, &xhci->op_regs->command);
+
+	return handshake(xhci, &xhci->op_regs->status,
+			STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC);
+}
+
+/*
+ * Reset a halted HC, and set the internal HC state to HC_STATE_HALT.
+ *
+ * This resets pipelines, timers, counters, state machines, etc.
+ * Transactions will be terminated immediately, and operational registers
+ * will be set to their defaults.
+ */
+int xhci_reset(struct xhci_hcd *xhci)
+{
+	u32 command;
+	u32 state;
+
+	state = xhci_readl(xhci, &xhci->op_regs->status);
+	BUG_ON((state & STS_HALT) == 0);
+
+	xhci_dbg(xhci, "// Reset the HC\n");
+	command = xhci_readl(xhci, &xhci->op_regs->command);
+	command |= CMD_RESET;
+	xhci_writel(xhci, command, &xhci->op_regs->command);
+	/* XXX: Why does EHCI set this here?  Shouldn't other code do this? */
+	xhci_to_hcd(xhci)->state = HC_STATE_HALT;
+
+	return handshake(xhci, &xhci->op_regs->command, CMD_RESET, 0, 250 * 1000);
+}
+
+/*
+ * Stop the HC from processing the endpoint queues.
+ */
+static void xhci_quiesce(struct xhci_hcd *xhci)
+{
+	/*
+	 * Queues are per endpoint, so we need to disable an endpoint or slot.
+	 *
+	 * To disable a slot, we need to insert a disable slot command on the
+	 * command ring and ring the doorbell.  This will also free any internal
+	 * resources associated with the slot (which might not be what we want).
+	 *
+	 * A Release Endpoint command sounds better - doesn't free internal HC
+	 * memory, but removes the endpoints from the schedule and releases the
+	 * bandwidth, disables the doorbells, and clears the endpoint enable
+	 * flag.  Usually used prior to a set interface command.
+	 *
+	 * TODO: Implement after command ring code is done.
+	 */
+	BUG_ON(!HC_IS_RUNNING(xhci_to_hcd(xhci)->state));
+	xhci_dbg(xhci, "Finished quiescing -- code not written yet\n");
+}
+
+#if 0
+/* Set up MSI-X table for entry 0 (may claim other entries later) */
+static int xhci_setup_msix(struct xhci_hcd *xhci)
+{
+	int ret;
+	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
+
+	xhci->msix_count = 0;
+	/* XXX: did I do this right?  ixgbe does kcalloc for more than one */
+	xhci->msix_entries = kmalloc(sizeof(struct msix_entry), GFP_KERNEL);
+	if (!xhci->msix_entries) {
+		xhci_err(xhci, "Failed to allocate MSI-X entries\n");
+		return -ENOMEM;
+	}
+	xhci->msix_entries[0].entry = 0;
+
+	ret = pci_enable_msix(pdev, xhci->msix_entries, xhci->msix_count);
+	if (ret) {
+		xhci_err(xhci, "Failed to enable MSI-X\n");
+		goto free_entries;
+	}
+
+	/*
+	 * Pass the xhci pointer value as the request_irq "cookie".
+	 * If more irqs are added, this will need to be unique for each one.
+	 */
+	ret = request_irq(xhci->msix_entries[0].vector, &xhci_irq, 0,
+			"xHCI", xhci_to_hcd(xhci));
+	if (ret) {
+		xhci_err(xhci, "Failed to allocate MSI-X interrupt\n");
+		goto disable_msix;
+	}
+	xhci_dbg(xhci, "Finished setting up MSI-X\n");
+	return 0;
+
+disable_msix:
+	pci_disable_msix(pdev);
+free_entries:
+	kfree(xhci->msix_entries);
+	xhci->msix_entries = NULL;
+	return ret;
+}
+
+/* XXX: code duplication; can xhci_setup_msix call this? */
+/* Free any IRQs and disable MSI-X */
+static void xhci_cleanup_msix(struct xhci_hcd *xhci)
+{
+	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
+	if (!xhci->msix_entries)
+		return;
+
+	free_irq(xhci->msix_entries[0].vector, xhci);
+	pci_disable_msix(pdev);
+	kfree(xhci->msix_entries);
+	xhci->msix_entries = NULL;
+	xhci_dbg(xhci, "Finished cleaning up MSI-X\n");
+}
+#endif
+
+/*
+ * Initialize memory for HCD and xHC (one-time init).
+ *
+ * Program the PAGESIZE register, initialize the device context array, create
+ * device contexts (?), set up a command ring segment (or two?), create event
+ * ring (one for now).
+ */
+int xhci_init(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	int retval = 0;
+
+	xhci_dbg(xhci, "xhci_init\n");
+	spin_lock_init(&xhci->lock);
+	retval = xhci_mem_init(xhci, GFP_KERNEL);
+	xhci_dbg(xhci, "Finished xhci_init\n");
+
+	return retval;
+}
+
+/*
+ * Start the HC after it was halted.
+ *
+ * This function is called by the USB core when the HC driver is added.
+ * Its opposite is xhci_stop().
+ *
+ * xhci_init() must be called once before this function can be called.
+ * Reset the HC, enable device slot contexts, program DCBAAP, and
+ * set command ring pointer and event ring pointer.
+ *
+ * Setup MSI-X vectors and enable interrupts.
+ */
+int xhci_run(struct usb_hcd *hcd)
+{
+	u32 temp;
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	xhci_dbg(xhci, "xhci_run\n");
+
+#if 0	/* FIXME: MSI not setup yet */
+	/* Do this at the very last minute */
+	ret = xhci_setup_msix(xhci);
+	if (!ret)
+		return ret;
+
+	return -ENOSYS;
+#endif
+	xhci_dbg(xhci, "// Set the interrupt modulation register\n");
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_control);
+	temp &= 0xffff;
+	temp |= (u32) 160;
+	xhci_writel(xhci, temp, &xhci->ir_set->irq_control);
+
+	/* Set the HCD state before we enable the irqs */
+	hcd->state = HC_STATE_RUNNING;
+	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	temp |= (CMD_EIE);
+	xhci_dbg(xhci, "// Enable interrupts, cmd = 0x%x.\n",
+			temp);
+	xhci_writel(xhci, temp, &xhci->op_regs->command);
+
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+	xhci_dbg(xhci, "// Enabling event ring interrupter 0x%x"
+			" by writing 0x%x to irq_pending\n",
+			(unsigned int) xhci->ir_set,
+			(unsigned int) ER_IRQ_ENABLE(temp));
+	xhci_writel(xhci, ER_IRQ_ENABLE(temp),
+			&xhci->ir_set->irq_pending);
+	xhci_print_ir_set(xhci, xhci->ir_set, 0);
+
+	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	temp |= (CMD_RUN);
+	xhci_dbg(xhci, "// Turn on HC, cmd = 0x%x.\n",
+			temp);
+	xhci_writel(xhci, temp, &xhci->op_regs->command);
+	/* Flush PCI posted writes */
+	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	xhci_dbg(xhci, "// @%x = 0x%x\n",
+			(unsigned int) &xhci->op_regs->command, temp);
+
+	xhci_dbg(xhci, "Finished xhci_run\n");
+	return 0;
+}
+
+/*
+ * Stop xHCI driver.
+ *
+ * This function is called by the USB core when the HC driver is removed.
+ * Its opposite is xhci_run().
+ *
+ * Disable device contexts, disable IRQs, and quiesce the HC.
+ * Reset the HC, finish any completed transactions, and cleanup memory.
+ */
+void xhci_stop(struct usb_hcd *hcd)
+{
+	u32 temp;
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+
+	spin_lock_irq(&xhci->lock);
+	if (HC_IS_RUNNING(hcd->state))
+		xhci_quiesce(xhci);
+	xhci_halt(xhci);
+	xhci_reset(xhci);
+	spin_unlock_irq(&xhci->lock);
+
+#if 0	/* No MSI yet */
+	xhci_cleanup_msix(xhci);
+#endif
+	xhci_dbg(xhci, "// Disabling event ring interrupts\n");
+	temp = xhci_readl(xhci, &xhci->op_regs->status);
+	xhci_writel(xhci, temp & ~STS_EINT, &xhci->op_regs->status);
+	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
+	xhci_writel(xhci, ER_IRQ_DISABLE(temp),
+			&xhci->ir_set->irq_pending);
+	xhci_print_ir_set(xhci, xhci->ir_set, 0);
+
+	xhci_dbg(xhci, "cleaning up memory\n");
+	xhci_mem_cleanup(xhci);
+	xhci_dbg(xhci, "xhci_stop completed - status = %x\n",
+		    xhci_readl(xhci, &xhci->op_regs->status));
+}
+
+/*
+ * Shutdown HC (not bus-specific)
+ *
+ * This is called when the machine is rebooting or halting.  We assume that the
+ * machine will be powered off, and the HC's internal state will be reset.
+ * Don't bother to free memory.
+ */
+void xhci_shutdown(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+
+	spin_lock_irq(&xhci->lock);
+	xhci_halt(xhci);
+	spin_unlock_irq(&xhci->lock);
+
+#if 0
+	xhci_cleanup_msix(xhci);
+#endif
+
+	xhci_dbg(xhci, "xhci_shutdown completed - status = %x\n",
+		    xhci_readl(xhci, &xhci->op_regs->status));
+}
+
+int xhci_get_frame(struct usb_hcd *hcd)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+	/* EHCI mods by the periodic size.  Why? */
+	return xhci_readl(xhci, &xhci->run_regs->microframe_index) >> 3;
+}
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_LICENSE("GPL");
+
+static int __init xhci_hcd_init(void)
+{
+#ifdef CONFIG_PCI
+	int retval = 0;
+
+	retval = xhci_register_pci();
+
+	if (retval < 0) {
+		printk(KERN_DEBUG "Problem registering PCI driver.");
+		return retval;
+	}
+#endif
+	return 0;
+}
+module_init(xhci_hcd_init);
+
+static void __exit xhci_hcd_cleanup(void)
+{
+#ifdef CONFIG_PCI
+	xhci_unregister_pci();
+#endif
+}
+module_exit(xhci_hcd_cleanup);
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
new file mode 100644
index 0000000000000000000000000000000000000000..0e383f9c380ca5337fb2c043ce735068e0a00fe7
--- /dev/null
+++ b/drivers/usb/host/xhci-mem.c
@@ -0,0 +1,75 @@
+/*
+ * xHCI host controller driver
+ *
+ * Copyright (C) 2008 Intel Corp.
+ *
+ * Author: Sarah Sharp
+ * Some code borrowed from the Linux EHCI driver.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/usb.h>
+
+#include "xhci.h"
+
+void xhci_mem_cleanup(struct xhci_hcd *xhci)
+{
+	xhci->page_size = 0;
+	xhci->page_shift = 0;
+}
+
+int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
+{
+	unsigned int	val, val2;
+	u32 page_size;
+	int i;
+
+	page_size = xhci_readl(xhci, &xhci->op_regs->page_size);
+	xhci_dbg(xhci, "Supported page size register = 0x%x\n", page_size);
+	for (i = 0; i < 16; i++) {
+		if ((0x1 & page_size) != 0)
+			break;
+		page_size = page_size >> 1;
+	}
+	if (i < 16)
+		xhci_dbg(xhci, "Supported page size of %iK\n", (1 << (i+12)) / 1024);
+	else
+		xhci_warn(xhci, "WARN: no supported page size\n");
+	/* Use 4K pages, since that's common and the minimum the HC supports */
+	xhci->page_shift = 12;
+	xhci->page_size = 1 << xhci->page_shift;
+	xhci_dbg(xhci, "HCD page size set to %iK\n", xhci->page_size / 1024);
+
+	/*
+	 * Program the Number of Device Slots Enabled field in the CONFIG
+	 * register with the max value of slots the HC can handle.
+	 */
+	val = HCS_MAX_SLOTS(xhci_readl(xhci, &xhci->cap_regs->hcs_params1));
+	xhci_dbg(xhci, "// xHC can handle at most %d device slots.\n",
+			(unsigned int) val);
+	val2 = xhci_readl(xhci, &xhci->op_regs->config_reg);
+	val |= (val2 & ~HCS_SLOTS_MASK);
+	xhci_dbg(xhci, "// Setting Max device slots reg = 0x%x.\n",
+			(unsigned int) val);
+	xhci_writel(xhci, val, &xhci->op_regs->config_reg);
+
+	xhci->ir_set = &xhci->run_regs->ir_set[0];
+
+	return 0;
+fail:
+	xhci_warn(xhci, "Couldn't initialize memory\n");
+	xhci_mem_cleanup(xhci);
+	return -ENOMEM;
+}
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
new file mode 100644
index 0000000000000000000000000000000000000000..4015082adf60037e221cff5625ffdc5115b06687
--- /dev/null
+++ b/drivers/usb/host/xhci-pci.c
@@ -0,0 +1,150 @@
+/*
+ * xHCI host controller driver PCI Bus Glue.
+ *
+ * Copyright (C) 2008 Intel Corp.
+ *
+ * Author: Sarah Sharp
+ * Some code borrowed from the Linux EHCI driver.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/pci.h>
+
+#include "xhci.h"
+
+static const char hcd_name[] = "xhci_hcd";
+
+/* called after powerup, by probe or system-pm "wakeup" */
+static int xhci_pci_reinit(struct xhci_hcd *xhci, struct pci_dev *pdev)
+{
+	/*
+	 * TODO: Implement finding debug ports later.
+	 * TODO: see if there are any quirks that need to be added to handle
+	 * new extended capabilities.
+	 */
+
+	/* PCI Memory-Write-Invalidate cycle support is optional (uncommon) */
+	if (!pci_set_mwi(pdev))
+		xhci_dbg(xhci, "MWI active\n");
+
+	xhci_dbg(xhci, "Finished xhci_pci_reinit\n");
+	return 0;
+}
+
+/* called during probe() after chip reset completes */
+static int xhci_pci_setup(struct usb_hcd *hcd)
+{
+	struct xhci_hcd		*xhci = hcd_to_xhci(hcd);
+	struct pci_dev		*pdev = to_pci_dev(hcd->self.controller);
+	int			retval;
+
+	xhci->cap_regs = hcd->regs;
+	xhci->op_regs = hcd->regs +
+		HC_LENGTH(xhci_readl(xhci, &xhci->cap_regs->hc_capbase));
+	xhci->run_regs = hcd->regs +
+		(xhci_readl(xhci, &xhci->cap_regs->run_regs_off) & RTSOFF_MASK);
+	/* Cache read-only capability registers */
+	xhci->hcs_params1 = xhci_readl(xhci, &xhci->cap_regs->hcs_params1);
+	xhci->hcs_params2 = xhci_readl(xhci, &xhci->cap_regs->hcs_params2);
+	xhci->hcs_params3 = xhci_readl(xhci, &xhci->cap_regs->hcs_params3);
+	xhci->hcc_params = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
+	xhci_print_registers(xhci);
+
+	/* Make sure the HC is halted. */
+	retval = xhci_halt(xhci);
+	if (retval)
+		return retval;
+
+	xhci_dbg(xhci, "Resetting HCD\n");
+	/* Reset the internal HC memory state and registers. */
+	retval = xhci_reset(xhci);
+	if (retval)
+		return retval;
+	xhci_dbg(xhci, "Reset complete\n");
+
+	xhci_dbg(xhci, "Calling HCD init\n");
+	/* Initialize HCD and host controller data structures. */
+	retval = xhci_init(hcd);
+	if (retval)
+		return retval;
+	xhci_dbg(xhci, "Called HCD init\n");
+
+	pci_read_config_byte(pdev, XHCI_SBRN_OFFSET, &xhci->sbrn);
+	xhci_dbg(xhci, "Got SBRN %u\n", (unsigned int) xhci->sbrn);
+
+	/* Find any debug ports */
+	return xhci_pci_reinit(xhci, pdev);
+}
+
+static const struct hc_driver xhci_pci_hc_driver = {
+	.description =		hcd_name,
+	.product_desc =		"xHCI Host Controller",
+	.hcd_priv_size =	sizeof(struct xhci_hcd),
+
+	/*
+	 * generic hardware linkage
+	 */
+	.flags =		HCD_MEMORY | HCD_USB3,
+
+	/*
+	 * basic lifecycle operations
+	 */
+	.reset =		xhci_pci_setup,
+	.start =		xhci_run,
+	/* suspend and resume implemented later */
+	.stop =			xhci_stop,
+	.shutdown =		xhci_shutdown,
+
+	/*
+	 * scheduling support
+	 */
+	.get_frame_number =	xhci_get_frame,
+
+	/* Implement root hub support later. */
+};
+
+/*-------------------------------------------------------------------------*/
+
+/* PCI driver selection metadata; PCI hotplugging uses this */
+static const struct pci_device_id pci_ids[] = { {
+	/* handle any USB 3.0 xHCI controller */
+	PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_XHCI, ~0),
+	.driver_data =	(unsigned long) &xhci_pci_hc_driver,
+	},
+	{ /* end: all zeroes */ }
+};
+MODULE_DEVICE_TABLE(pci, pci_ids);
+
+/* pci driver glue; this is a "new style" PCI driver module */
+static struct pci_driver xhci_pci_driver = {
+	.name =		(char *) hcd_name,
+	.id_table =	pci_ids,
+
+	.probe =	usb_hcd_pci_probe,
+	.remove =	usb_hcd_pci_remove,
+	/* suspend and resume implemented later */
+
+	.shutdown = 	usb_hcd_pci_shutdown,
+};
+
+int xhci_register_pci()
+{
+	return pci_register_driver(&xhci_pci_driver);
+}
+
+void xhci_unregister_pci()
+{
+	pci_unregister_driver(&xhci_pci_driver);
+}
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index a4d44aad06973a465914f5025e291a03bec7617b..59fae2e5ea59ab246cdc2acbc47343392ca23fae 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -32,6 +32,9 @@
 /* xHCI PCI Configuration Registers */
 #define XHCI_SBRN_OFFSET	(0x60)
 
+/* Max number of USB devices for any host controller - limit in section 6.1 */
+#define MAX_HC_SLOTS		256
+
 /*
  * xHCI register interface.
  * This corresponds to the eXtensible Host Controller Interface (xHCI)
@@ -359,10 +362,35 @@ struct intr_reg {
 	u32	erst_dequeue[2];
 } __attribute__ ((packed));
 
+/* irq_pending bitmasks */
 #define	ER_IRQ_PENDING(p)	((p) & 0x1)
-#define	ER_IRQ_ENABLE(p)	((p) | 0x2)
+/* bits 2:31 need to be preserved */
+#define	ER_IRQ_CLEAR(p)		((p) & 0xfffffffe)
+#define	ER_IRQ_ENABLE(p)	((ER_IRQ_CLEAR(p)) | 0x2)
+#define	ER_IRQ_DISABLE(p)	((ER_IRQ_CLEAR(p)) & ~(0x2))
+
+/* irq_control bitmasks */
+/* Minimum interval between interrupts (in 250ns intervals).  The interval
+ * between interrupts will be longer if there are no events on the event ring.
+ * Default is 4000 (1 ms).
+ */
+#define ER_IRQ_INTERVAL_MASK	(0xffff)
+/* Counter used to count down the time to the next interrupt - HW use only */
+#define ER_IRQ_COUNTER_MASK	(0xffff << 16)
+
+/* erst_size bitmasks */
 /* Preserve bits 16:31 of erst_size */
-#define	ERST_SIZE_MASK	(0xffff<<16)
+#define	ERST_SIZE_MASK		(0xffff << 16)
+
+/* erst_dequeue bitmasks */
+/* Dequeue ERST Segment Index (DESI) - Segment number (or alias)
+ * where the current dequeue pointer lies.  This is an optional HW hint.
+ */
+#define ERST_DESI_MASK		(0x7)
+/* Event Handler Busy (EHB) - is the event ring scheduled to be serviced by
+ * a work queue (or delayed service routine)?
+ */
+#define ERST_EHB		(1 << 3)
 
 /**
  * struct xhci_run_regs
@@ -386,6 +414,8 @@ struct xhci_hcd {
 	struct xhci_cap_regs __iomem *cap_regs;
 	struct xhci_op_regs __iomem *op_regs;
 	struct xhci_run_regs __iomem *run_regs;
+	/* Our HCD's current interrupter register set */
+	struct	intr_reg __iomem *ir_set;
 
 	/* Cached register copies of read-only HC data */
 	__u32		hcs_params1;
@@ -404,7 +434,13 @@ struct xhci_hcd {
 	u8		isoc_threshold;
 	int		event_ring_max;
 	int		addr_64;
+	/* 4KB min, 128MB max */
 	int		page_size;
+	/* Valid values are 12 to 20, inclusive */
+	int		page_shift;
+	/* only one MSI vector for now, but might need more later */
+	int		msix_count;
+	struct msix_entry	*msix_entries;
 };
 
 /* convert between an HCD pointer and the corresponding EHCI_HCD */
@@ -449,4 +485,27 @@ static inline void xhci_writel(const struct xhci_hcd *xhci,
 	writel(val, regs);
 }
 
+/* xHCI debugging */
+void xhci_print_ir_set(struct xhci_hcd *xhci, struct intr_reg *ir_set, int set_num);
+void xhci_print_registers(struct xhci_hcd *xhci);
+
+/* xHCI memory managment */
+void xhci_mem_cleanup(struct xhci_hcd *xhci);
+int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags);
+
+#ifdef CONFIG_PCI
+/* xHCI PCI glue */
+int xhci_register_pci(void);
+void xhci_unregister_pci(void);
+#endif
+
+/* xHCI host controller glue */
+int xhci_halt(struct xhci_hcd *xhci);
+int xhci_reset(struct xhci_hcd *xhci);
+int xhci_init(struct usb_hcd *hcd);
+int xhci_run(struct usb_hcd *hcd);
+void xhci_stop(struct usb_hcd *hcd);
+void xhci_shutdown(struct usb_hcd *hcd);
+int xhci_get_frame(struct usb_hcd *hcd);
+
 #endif /* __LINUX_XHCI_HCD_H */
diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index aa01d38c9971a745feec8bb70b0fa93392dcc08e..a3b0003657955da3651542059572387fda381308 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -104,6 +104,7 @@
 #define PCI_CLASS_SERIAL_USB_UHCI	0x0c0300
 #define PCI_CLASS_SERIAL_USB_OHCI	0x0c0310
 #define PCI_CLASS_SERIAL_USB_EHCI	0x0c0320
+#define PCI_CLASS_SERIAL_USB_XHCI	0x0c0330
 #define PCI_CLASS_SERIAL_FIBER		0x0c04
 #define PCI_CLASS_SERIAL_SMBUS		0x0c05