[PATCH] pci/vmd: Move vmd driver to drivers/pci/host

[Keith Busch <keith.busch@intel.com>]

This moves the driver source and Kconfig to the pci host bridge drivers
directory, relocating the config option to a more approrpiate sub-menu
instead of occupying the top level location.

The Kconfig option for VMD has been updated with its X86_64 dependency
that was implicitly included from the previous location, and added
missing information for building this driver as a loadable module.

Cc: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
---
 arch/x86/Kconfig          |  13 -
 arch/x86/pci/Makefile     |   2 -
 arch/x86/pci/vmd.c        | 766 ----------------------------------------------
 drivers/pci/host/Kconfig  |  16 +
 drivers/pci/host/Makefile |   1 +
 drivers/pci/host/vmd.c    | 766 ++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 783 insertions(+), 781 deletions(-)
 delete mode 100644 arch/x86/pci/vmd.c
 create mode 100644 drivers/pci/host/vmd.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 5c6e747..c320838 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2744,19 +2744,6 @@ config PMC_ATOM
 	def_bool y
         depends on PCI
 
-config VMD
-	depends on PCI_MSI
-	tristate "Volume Management Device Driver"
-	default N
-	---help---
-	  Adds support for the Intel Volume Management Device (VMD). VMD is a
-	  secondary PCI host bridge that allows PCI Express root ports,
-	  and devices attached to them, to be removed from the default
-	  PCI domain and placed within the VMD domain. This provides
-	  more bus resources than are otherwise possible with a
-	  single domain. If you know your system provides one of these and
-	  has devices attached to it, say Y; if you are not sure, say N.
-
 source "net/Kconfig"
 
 source "drivers/Kconfig"
diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile
index 97062a6..5c6fc35 100644
--- a/arch/x86/pci/Makefile
+++ b/arch/x86/pci/Makefile
@@ -23,8 +23,6 @@ obj-y				+= bus_numa.o
 obj-$(CONFIG_AMD_NB)		+= amd_bus.o
 obj-$(CONFIG_PCI_CNB20LE_QUIRK)	+= broadcom_bus.o
 
-obj-$(CONFIG_VMD) += vmd.o
-
 ifeq ($(CONFIG_PCI_DEBUG),y)
 EXTRA_CFLAGS += -DDEBUG
 endif
diff --git a/arch/x86/pci/vmd.c b/arch/x86/pci/vmd.c
deleted file mode 100644
index a021b7b..0000000
--- a/arch/x86/pci/vmd.c
+++ /dev/null
@@ -1,766 +0,0 @@
-/*
- * Volume Management Device driver
- * Copyright (c) 2015, Intel Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope 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.
- */
-
-#include <linux/device.h>
-#include <linux/interrupt.h>
-#include <linux/irq.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/msi.h>
-#include <linux/pci.h>
-#include <linux/rculist.h>
-#include <linux/rcupdate.h>
-
-#include <asm/irqdomain.h>
-#include <asm/device.h>
-#include <asm/msi.h>
-#include <asm/msidef.h>
-
-#define VMD_CFGBAR	0
-#define VMD_MEMBAR1	2
-#define VMD_MEMBAR2	4
-
-/*
- * Lock for manipulating VMD IRQ lists.
- */
-static DEFINE_RAW_SPINLOCK(list_lock);
-
-/**
- * struct vmd_irq - private data to map driver IRQ to the VMD shared vector
- * @node:	list item for parent traversal.
- * @rcu:	RCU callback item for freeing.
- * @irq:	back pointer to parent.
- * @virq:	the virtual IRQ value provided to the requesting driver.
- *
- * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
- * a VMD IRQ using this structure.
- */
-struct vmd_irq {
-	struct list_head	node;
-	struct rcu_head		rcu;
-	struct vmd_irq_list	*irq;
-	unsigned int		virq;
-};
-
-/**
- * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
- * @irq_list:	the list of irq's the VMD one demuxes to.
- * @vmd_vector:	the h/w IRQ assigned to the VMD.
- * @index:	index into the VMD MSI-X table; used for message routing.
- * @count:	number of child IRQs assigned to this vector; used to track
- *		sharing.
- */
-struct vmd_irq_list {
-	struct list_head	irq_list;
-	struct vmd_dev		*vmd;
-	unsigned int		vmd_vector;
-	unsigned int		index;
-	unsigned int		count;
-};
-
-struct vmd_dev {
-	struct pci_dev		*dev;
-
-	spinlock_t		cfg_lock;
-	char __iomem		*cfgbar;
-
-	int msix_count;
-	struct msix_entry	*msix_entries;
-	struct vmd_irq_list	*irqs;
-
-	struct pci_sysdata	sysdata;
-	struct resource		resources[3];
-	struct irq_domain	*irq_domain;
-	struct pci_bus		*bus;
-
-#ifdef CONFIG_X86_DEV_DMA_OPS
-	struct dma_map_ops	dma_ops;
-	struct dma_domain	dma_domain;
-#endif
-};
-
-static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
-{
-	return container_of(bus->sysdata, struct vmd_dev, sysdata);
-}
-
-/*
- * Drivers managing a device in a VMD domain allocate their own IRQs as before,
- * but the MSI entry for the hardware it's driving will be programmed with a
- * destination ID for the VMD MSI-X table.  The VMD muxes interrupts in its
- * domain into one of its own, and the VMD driver de-muxes these for the
- * handlers sharing that VMD IRQ.  The vmd irq_domain provides the operations
- * and irq_chip to set this up.
- */
-static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
-{
-	struct vmd_irq *vmdirq = data->chip_data;
-	struct vmd_irq_list *irq = vmdirq->irq;
-
-	msg->address_hi = MSI_ADDR_BASE_HI;
-	msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_DEST_ID(irq->index);
-	msg->data = 0;
-}
-
-/*
- * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
- */
-static void vmd_irq_enable(struct irq_data *data)
-{
-	struct vmd_irq *vmdirq = data->chip_data;
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&list_lock, flags);
-	list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
-	raw_spin_unlock_irqrestore(&list_lock, flags);
-
-	data->chip->irq_unmask(data);
-}
-
-static void vmd_irq_disable(struct irq_data *data)
-{
-	struct vmd_irq *vmdirq = data->chip_data;
-	unsigned long flags;
-
-	data->chip->irq_mask(data);
-
-	raw_spin_lock_irqsave(&list_lock, flags);
-	list_del_rcu(&vmdirq->node);
-	INIT_LIST_HEAD_RCU(&vmdirq->node);
-	raw_spin_unlock_irqrestore(&list_lock, flags);
-}
-
-/*
- * XXX: Stubbed until we develop acceptable way to not create conflicts with
- * other devices sharing the same vector.
- */
-static int vmd_irq_set_affinity(struct irq_data *data,
-				const struct cpumask *dest, bool force)
-{
-	return -EINVAL;
-}
-
-static struct irq_chip vmd_msi_controller = {
-	.name			= "VMD-MSI",
-	.irq_enable		= vmd_irq_enable,
-	.irq_disable		= vmd_irq_disable,
-	.irq_compose_msi_msg	= vmd_compose_msi_msg,
-	.irq_set_affinity	= vmd_irq_set_affinity,
-};
-
-static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
-				     msi_alloc_info_t *arg)
-{
-	return 0;
-}
-
-/*
- * XXX: We can be even smarter selecting the best IRQ once we solve the
- * affinity problem.
- */
-static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
-{
-	int i, best = 1;
-	unsigned long flags;
-
-	if (!desc->msi_attrib.is_msix || vmd->msix_count == 1)
-		return &vmd->irqs[0];
-
-	raw_spin_lock_irqsave(&list_lock, flags);
-	for (i = 1; i < vmd->msix_count; i++)
-		if (vmd->irqs[i].count < vmd->irqs[best].count)
-			best = i;
-	vmd->irqs[best].count++;
-	raw_spin_unlock_irqrestore(&list_lock, flags);
-
-	return &vmd->irqs[best];
-}
-
-static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
-			unsigned int virq, irq_hw_number_t hwirq,
-			msi_alloc_info_t *arg)
-{
-	struct msi_desc *desc = arg->desc;
-	struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
-	struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
-
-	if (!vmdirq)
-		return -ENOMEM;
-
-	INIT_LIST_HEAD(&vmdirq->node);
-	vmdirq->irq = vmd_next_irq(vmd, desc);
-	vmdirq->virq = virq;
-
-	irq_domain_set_info(domain, virq, vmdirq->irq->vmd_vector, info->chip,
-			    vmdirq, handle_untracked_irq, vmd, NULL);
-	return 0;
-}
-
-static void vmd_msi_free(struct irq_domain *domain,
-			struct msi_domain_info *info, unsigned int virq)
-{
-	struct vmd_irq *vmdirq = irq_get_chip_data(virq);
-	unsigned long flags;
-
-	/* XXX: Potential optimization to rebalance */
-	raw_spin_lock_irqsave(&list_lock, flags);
-	vmdirq->irq->count--;
-	raw_spin_unlock_irqrestore(&list_lock, flags);
-
-	kfree_rcu(vmdirq, rcu);
-}
-
-static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
-			   int nvec, msi_alloc_info_t *arg)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
-
-	if (nvec > vmd->msix_count)
-		return vmd->msix_count;
-
-	memset(arg, 0, sizeof(*arg));
-	return 0;
-}
-
-static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
-{
-	arg->desc = desc;
-}
-
-static struct msi_domain_ops vmd_msi_domain_ops = {
-	.get_hwirq	= vmd_get_hwirq,
-	.msi_init	= vmd_msi_init,
-	.msi_free	= vmd_msi_free,
-	.msi_prepare	= vmd_msi_prepare,
-	.set_desc	= vmd_set_desc,
-};
-
-static struct msi_domain_info vmd_msi_domain_info = {
-	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
-			  MSI_FLAG_PCI_MSIX,
-	.ops		= &vmd_msi_domain_ops,
-	.chip		= &vmd_msi_controller,
-};
-
-#ifdef CONFIG_X86_DEV_DMA_OPS
-/*
- * VMD replaces the requester ID with its own.  DMA mappings for devices in a
- * VMD domain need to be mapped for the VMD, not the device requiring
- * the mapping.
- */
-static struct device *to_vmd_dev(struct device *dev)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
-
-	return &vmd->dev->dev;
-}
-
-static struct dma_map_ops *vmd_dma_ops(struct device *dev)
-{
-	return get_dma_ops(to_vmd_dev(dev));
-}
-
-static void *vmd_alloc(struct device *dev, size_t size, dma_addr_t *addr,
-		       gfp_t flag, unsigned long attrs)
-{
-	return vmd_dma_ops(dev)->alloc(to_vmd_dev(dev), size, addr, flag,
-				       attrs);
-}
-
-static void vmd_free(struct device *dev, size_t size, void *vaddr,
-		     dma_addr_t addr, unsigned long attrs)
-{
-	return vmd_dma_ops(dev)->free(to_vmd_dev(dev), size, vaddr, addr,
-				      attrs);
-}
-
-static int vmd_mmap(struct device *dev, struct vm_area_struct *vma,
-		    void *cpu_addr, dma_addr_t addr, size_t size,
-		    unsigned long attrs)
-{
-	return vmd_dma_ops(dev)->mmap(to_vmd_dev(dev), vma, cpu_addr, addr,
-				      size, attrs);
-}
-
-static int vmd_get_sgtable(struct device *dev, struct sg_table *sgt,
-			   void *cpu_addr, dma_addr_t addr, size_t size,
-			   unsigned long attrs)
-{
-	return vmd_dma_ops(dev)->get_sgtable(to_vmd_dev(dev), sgt, cpu_addr,
-					     addr, size, attrs);
-}
-
-static dma_addr_t vmd_map_page(struct device *dev, struct page *page,
-			       unsigned long offset, size_t size,
-			       enum dma_data_direction dir,
-			       unsigned long attrs)
-{
-	return vmd_dma_ops(dev)->map_page(to_vmd_dev(dev), page, offset, size,
-					  dir, attrs);
-}
-
-static void vmd_unmap_page(struct device *dev, dma_addr_t addr, size_t size,
-			   enum dma_data_direction dir, unsigned long attrs)
-{
-	vmd_dma_ops(dev)->unmap_page(to_vmd_dev(dev), addr, size, dir, attrs);
-}
-
-static int vmd_map_sg(struct device *dev, struct scatterlist *sg, int nents,
-		      enum dma_data_direction dir, unsigned long attrs)
-{
-	return vmd_dma_ops(dev)->map_sg(to_vmd_dev(dev), sg, nents, dir, attrs);
-}
-
-static void vmd_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
-			 enum dma_data_direction dir, unsigned long attrs)
-{
-	vmd_dma_ops(dev)->unmap_sg(to_vmd_dev(dev), sg, nents, dir, attrs);
-}
-
-static void vmd_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
-				    size_t size, enum dma_data_direction dir)
-{
-	vmd_dma_ops(dev)->sync_single_for_cpu(to_vmd_dev(dev), addr, size, dir);
-}
-
-static void vmd_sync_single_for_device(struct device *dev, dma_addr_t addr,
-				       size_t size, enum dma_data_direction dir)
-{
-	vmd_dma_ops(dev)->sync_single_for_device(to_vmd_dev(dev), addr, size,
-						 dir);
-}
-
-static void vmd_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
-				int nents, enum dma_data_direction dir)
-{
-	vmd_dma_ops(dev)->sync_sg_for_cpu(to_vmd_dev(dev), sg, nents, dir);
-}
-
-static void vmd_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
-				   int nents, enum dma_data_direction dir)
-{
-	vmd_dma_ops(dev)->sync_sg_for_device(to_vmd_dev(dev), sg, nents, dir);
-}
-
-static int vmd_mapping_error(struct device *dev, dma_addr_t addr)
-{
-	return vmd_dma_ops(dev)->mapping_error(to_vmd_dev(dev), addr);
-}
-
-static int vmd_dma_supported(struct device *dev, u64 mask)
-{
-	return vmd_dma_ops(dev)->dma_supported(to_vmd_dev(dev), mask);
-}
-
-#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
-static u64 vmd_get_required_mask(struct device *dev)
-{
-	return vmd_dma_ops(dev)->get_required_mask(to_vmd_dev(dev));
-}
-#endif
-
-static void vmd_teardown_dma_ops(struct vmd_dev *vmd)
-{
-	struct dma_domain *domain = &vmd->dma_domain;
-
-	if (get_dma_ops(&vmd->dev->dev))
-		del_dma_domain(domain);
-}
-
-#define ASSIGN_VMD_DMA_OPS(source, dest, fn)	\
-	do {					\
-		if (source->fn)			\
-			dest->fn = vmd_##fn;	\
-	} while (0)
-
-static void vmd_setup_dma_ops(struct vmd_dev *vmd)
-{
-	const struct dma_map_ops *source = get_dma_ops(&vmd->dev->dev);
-	struct dma_map_ops *dest = &vmd->dma_ops;
-	struct dma_domain *domain = &vmd->dma_domain;
-
-	domain->domain_nr = vmd->sysdata.domain;
-	domain->dma_ops = dest;
-
-	if (!source)
-		return;
-	ASSIGN_VMD_DMA_OPS(source, dest, alloc);
-	ASSIGN_VMD_DMA_OPS(source, dest, free);
-	ASSIGN_VMD_DMA_OPS(source, dest, mmap);
-	ASSIGN_VMD_DMA_OPS(source, dest, get_sgtable);
-	ASSIGN_VMD_DMA_OPS(source, dest, map_page);
-	ASSIGN_VMD_DMA_OPS(source, dest, unmap_page);
-	ASSIGN_VMD_DMA_OPS(source, dest, map_sg);
-	ASSIGN_VMD_DMA_OPS(source, dest, unmap_sg);
-	ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_cpu);
-	ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_device);
-	ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_cpu);
-	ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_device);
-	ASSIGN_VMD_DMA_OPS(source, dest, mapping_error);
-	ASSIGN_VMD_DMA_OPS(source, dest, dma_supported);
-#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
-	ASSIGN_VMD_DMA_OPS(source, dest, get_required_mask);
-#endif
-	add_dma_domain(domain);
-}
-#undef ASSIGN_VMD_DMA_OPS
-#else
-static void vmd_teardown_dma_ops(struct vmd_dev *vmd) {}
-static void vmd_setup_dma_ops(struct vmd_dev *vmd) {}
-#endif
-
-static char __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
-				  unsigned int devfn, int reg, int len)
-{
-	char __iomem *addr = vmd->cfgbar +
-			     (bus->number << 20) + (devfn << 12) + reg;
-
-	if ((addr - vmd->cfgbar) + len >=
-	    resource_size(&vmd->dev->resource[VMD_CFGBAR]))
-		return NULL;
-
-	return addr;
-}
-
-/*
- * CPU may deadlock if config space is not serialized on some versions of this
- * hardware, so all config space access is done under a spinlock.
- */
-static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg,
-			int len, u32 *value)
-{
-	struct vmd_dev *vmd = vmd_from_bus(bus);
-	char __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
-	unsigned long flags;
-	int ret = 0;
-
-	if (!addr)
-		return -EFAULT;
-
-	spin_lock_irqsave(&vmd->cfg_lock, flags);
-	switch (len) {
-	case 1:
-		*value = readb(addr);
-		break;
-	case 2:
-		*value = readw(addr);
-		break;
-	case 4:
-		*value = readl(addr);
-		break;
-	default:
-		ret = -EINVAL;
-		break;
-	}
-	spin_unlock_irqrestore(&vmd->cfg_lock, flags);
-	return ret;
-}
-
-/*
- * VMD h/w converts non-posted config writes to posted memory writes. The
- * read-back in this function forces the completion so it returns only after
- * the config space was written, as expected.
- */
-static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg,
-			 int len, u32 value)
-{
-	struct vmd_dev *vmd = vmd_from_bus(bus);
-	char __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
-	unsigned long flags;
-	int ret = 0;
-
-	if (!addr)
-		return -EFAULT;
-
-	spin_lock_irqsave(&vmd->cfg_lock, flags);
-	switch (len) {
-	case 1:
-		writeb(value, addr);
-		readb(addr);
-		break;
-	case 2:
-		writew(value, addr);
-		readw(addr);
-		break;
-	case 4:
-		writel(value, addr);
-		readl(addr);
-		break;
-	default:
-		ret = -EINVAL;
-		break;
-	}
-	spin_unlock_irqrestore(&vmd->cfg_lock, flags);
-	return ret;
-}
-
-static struct pci_ops vmd_ops = {
-	.read		= vmd_pci_read,
-	.write		= vmd_pci_write,
-};
-
-static void vmd_attach_resources(struct vmd_dev *vmd)
-{
-	vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1];
-	vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2];
-}
-
-static void vmd_detach_resources(struct vmd_dev *vmd)
-{
-	vmd->dev->resource[VMD_MEMBAR1].child = NULL;
-	vmd->dev->resource[VMD_MEMBAR2].child = NULL;
-}
-
-/*
- * VMD domains start at 0x1000 to not clash with ACPI _SEG domains.
- */
-static int vmd_find_free_domain(void)
-{
-	int domain = 0xffff;
-	struct pci_bus *bus = NULL;
-
-	while ((bus = pci_find_next_bus(bus)) != NULL)
-		domain = max_t(int, domain, pci_domain_nr(bus));
-	return domain + 1;
-}
-
-static int vmd_enable_domain(struct vmd_dev *vmd)
-{
-	struct pci_sysdata *sd = &vmd->sysdata;
-	struct resource *res;
-	u32 upper_bits;
-	unsigned long flags;
-	LIST_HEAD(resources);
-
-	res = &vmd->dev->resource[VMD_CFGBAR];
-	vmd->resources[0] = (struct resource) {
-		.name  = "VMD CFGBAR",
-		.start = 0,
-		.end   = (resource_size(res) >> 20) - 1,
-		.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED,
-	};
-
-	/*
-	 * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can
-	 * put 32-bit resources in the window.
-	 *
-	 * There's no hardware reason why a 64-bit window *couldn't*
-	 * contain a 32-bit resource, but pbus_size_mem() computes the
-	 * bridge window size assuming a 64-bit window will contain no
-	 * 32-bit resources.  __pci_assign_resource() enforces that
-	 * artificial restriction to make sure everything will fit.
-	 *
-	 * The only way we could use a 64-bit non-prefechable MEMBAR is
-	 * if its address is <4GB so that we can convert it to a 32-bit
-	 * resource.  To be visible to the host OS, all VMD endpoints must
-	 * be initially configured by platform BIOS, which includes setting
-	 * up these resources.  We can assume the device is configured
-	 * according to the platform needs.
-	 */
-	res = &vmd->dev->resource[VMD_MEMBAR1];
-	upper_bits = upper_32_bits(res->end);
-	flags = res->flags & ~IORESOURCE_SIZEALIGN;
-	if (!upper_bits)
-		flags &= ~IORESOURCE_MEM_64;
-	vmd->resources[1] = (struct resource) {
-		.name  = "VMD MEMBAR1",
-		.start = res->start,
-		.end   = res->end,
-		.flags = flags,
-		.parent = res,
-	};
-
-	res = &vmd->dev->resource[VMD_MEMBAR2];
-	upper_bits = upper_32_bits(res->end);
-	flags = res->flags & ~IORESOURCE_SIZEALIGN;
-	if (!upper_bits)
-		flags &= ~IORESOURCE_MEM_64;
-	vmd->resources[2] = (struct resource) {
-		.name  = "VMD MEMBAR2",
-		.start = res->start + 0x2000,
-		.end   = res->end,
-		.flags = flags,
-		.parent = res,
-	};
-
-	sd->vmd_domain = true;
-	sd->domain = vmd_find_free_domain();
-	if (sd->domain < 0)
-		return sd->domain;
-
-	sd->node = pcibus_to_node(vmd->dev->bus);
-
-	vmd->irq_domain = pci_msi_create_irq_domain(NULL, &vmd_msi_domain_info,
-						    x86_vector_domain);
-	if (!vmd->irq_domain)
-		return -ENODEV;
-
-	pci_add_resource(&resources, &vmd->resources[0]);
-	pci_add_resource(&resources, &vmd->resources[1]);
-	pci_add_resource(&resources, &vmd->resources[2]);
-	vmd->bus = pci_create_root_bus(&vmd->dev->dev, 0, &vmd_ops, sd,
-				       &resources);
-	if (!vmd->bus) {
-		pci_free_resource_list(&resources);
-		irq_domain_remove(vmd->irq_domain);
-		return -ENODEV;
-	}
-
-	vmd_attach_resources(vmd);
-	vmd_setup_dma_ops(vmd);
-	dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain);
-	pci_rescan_bus(vmd->bus);
-
-	WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj,
-			       "domain"), "Can't create symlink to domain\n");
-	return 0;
-}
-
-static irqreturn_t vmd_irq(int irq, void *data)
-{
-	struct vmd_irq_list *irqs = data;
-	struct vmd_irq *vmdirq;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
-		generic_handle_irq(vmdirq->virq);
-	rcu_read_unlock();
-
-	return IRQ_HANDLED;
-}
-
-static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
-{
-	struct vmd_dev *vmd;
-	int i, err;
-
-	if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
-		return -ENOMEM;
-
-	vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
-	if (!vmd)
-		return -ENOMEM;
-
-	vmd->dev = dev;
-	err = pcim_enable_device(dev);
-	if (err < 0)
-		return err;
-
-	vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
-	if (!vmd->cfgbar)
-		return -ENOMEM;
-
-	pci_set_master(dev);
-	if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
-	    dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32)))
-		return -ENODEV;
-
-	vmd->msix_count = pci_msix_vec_count(dev);
-	if (vmd->msix_count < 0)
-		return -ENODEV;
-
-	vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
-				 GFP_KERNEL);
-	if (!vmd->irqs)
-		return -ENOMEM;
-
-	vmd->msix_entries = devm_kcalloc(&dev->dev, vmd->msix_count,
-					 sizeof(*vmd->msix_entries),
-					 GFP_KERNEL);
-	if (!vmd->msix_entries)
-		return -ENOMEM;
-	for (i = 0; i < vmd->msix_count; i++)
-		vmd->msix_entries[i].entry = i;
-
-	vmd->msix_count = pci_enable_msix_range(vmd->dev, vmd->msix_entries, 1,
-						vmd->msix_count);
-	if (vmd->msix_count < 0)
-		return vmd->msix_count;
-
-	for (i = 0; i < vmd->msix_count; i++) {
-		INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
-		vmd->irqs[i].vmd_vector = vmd->msix_entries[i].vector;
-		vmd->irqs[i].index = i;
-
-		err = devm_request_irq(&dev->dev, vmd->irqs[i].vmd_vector,
-				       vmd_irq, 0, "vmd", &vmd->irqs[i]);
-		if (err)
-			return err;
-	}
-
-	spin_lock_init(&vmd->cfg_lock);
-	pci_set_drvdata(dev, vmd);
-	err = vmd_enable_domain(vmd);
-	if (err)
-		return err;
-
-	dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
-		 vmd->sysdata.domain);
-	return 0;
-}
-
-static void vmd_remove(struct pci_dev *dev)
-{
-	struct vmd_dev *vmd = pci_get_drvdata(dev);
-
-	vmd_detach_resources(vmd);
-	pci_set_drvdata(dev, NULL);
-	sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
-	pci_stop_root_bus(vmd->bus);
-	pci_remove_root_bus(vmd->bus);
-	vmd_teardown_dma_ops(vmd);
-	irq_domain_remove(vmd->irq_domain);
-}
-
-#ifdef CONFIG_PM
-static int vmd_suspend(struct device *dev)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-
-	pci_save_state(pdev);
-	return 0;
-}
-
-static int vmd_resume(struct device *dev)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-
-	pci_restore_state(pdev);
-	return 0;
-}
-#endif
-static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume);
-
-static const struct pci_device_id vmd_ids[] = {
-	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x201d),},
-	{0,}
-};
-MODULE_DEVICE_TABLE(pci, vmd_ids);
-
-static struct pci_driver vmd_drv = {
-	.name		= "vmd",
-	.id_table	= vmd_ids,
-	.probe		= vmd_probe,
-	.remove		= vmd_remove,
-	.driver		= {
-		.pm	= &vmd_dev_pm_ops,
-	},
-};
-module_pci_driver(vmd_drv);
-
-MODULE_AUTHOR("Intel Corporation");
-MODULE_LICENSE("GPL v2");
-MODULE_VERSION("0.6");
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 9b485d8..93865eb 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -274,4 +274,20 @@ config PCIE_ARTPEC6
 	  Say Y here to enable PCIe controller support on Axis ARTPEC-6
 	  SoCs.  This PCIe controller uses the DesignWare core.
 
+config VMD
+	depends on PCI_MSI && X86_64
+	tristate "Intel Volume Management Device Driver"
+	default N
+	---help---
+	  Adds support for the Intel Volume Management Device (VMD). VMD is a
+	  secondary PCI host bridge that allows PCI Express root ports,
+	  and devices attached to them, to be removed from the default
+	  PCI domain and placed within the VMD domain. This provides
+	  more bus resources than are otherwise possible with a
+	  single domain. If you know your system provides one of these and
+	  has devices attached to it, say Y; if you are not sure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called vmd.
+
 endmenu
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 8843410..afea1c6 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -31,3 +31,4 @@ obj-$(CONFIG_PCI_HOST_THUNDER_ECAM) += pci-thunder-ecam.o
 obj-$(CONFIG_PCI_HOST_THUNDER_PEM) += pci-thunder-pem.o
 obj-$(CONFIG_PCIE_ARMADA_8K) += pcie-armada8k.o
 obj-$(CONFIG_PCIE_ARTPEC6) += pcie-artpec6.o
+obj-$(CONFIG_VMD) += vmd.o
diff --git a/drivers/pci/host/vmd.c b/drivers/pci/host/vmd.c
new file mode 100644
index 0000000..a021b7b
--- /dev/null
+++ b/drivers/pci/host/vmd.c
@@ -0,0 +1,766 @@
+/*
+ * Volume Management Device driver
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/pci.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+
+#include <asm/irqdomain.h>
+#include <asm/device.h>
+#include <asm/msi.h>
+#include <asm/msidef.h>
+
+#define VMD_CFGBAR	0
+#define VMD_MEMBAR1	2
+#define VMD_MEMBAR2	4
+
+/*
+ * Lock for manipulating VMD IRQ lists.
+ */
+static DEFINE_RAW_SPINLOCK(list_lock);
+
+/**
+ * struct vmd_irq - private data to map driver IRQ to the VMD shared vector
+ * @node:	list item for parent traversal.
+ * @rcu:	RCU callback item for freeing.
+ * @irq:	back pointer to parent.
+ * @virq:	the virtual IRQ value provided to the requesting driver.
+ *
+ * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to
+ * a VMD IRQ using this structure.
+ */
+struct vmd_irq {
+	struct list_head	node;
+	struct rcu_head		rcu;
+	struct vmd_irq_list	*irq;
+	unsigned int		virq;
+};
+
+/**
+ * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
+ * @irq_list:	the list of irq's the VMD one demuxes to.
+ * @vmd_vector:	the h/w IRQ assigned to the VMD.
+ * @index:	index into the VMD MSI-X table; used for message routing.
+ * @count:	number of child IRQs assigned to this vector; used to track
+ *		sharing.
+ */
+struct vmd_irq_list {
+	struct list_head	irq_list;
+	struct vmd_dev		*vmd;
+	unsigned int		vmd_vector;
+	unsigned int		index;
+	unsigned int		count;
+};
+
+struct vmd_dev {
+	struct pci_dev		*dev;
+
+	spinlock_t		cfg_lock;
+	char __iomem		*cfgbar;
+
+	int msix_count;
+	struct msix_entry	*msix_entries;
+	struct vmd_irq_list	*irqs;
+
+	struct pci_sysdata	sysdata;
+	struct resource		resources[3];
+	struct irq_domain	*irq_domain;
+	struct pci_bus		*bus;
+
+#ifdef CONFIG_X86_DEV_DMA_OPS
+	struct dma_map_ops	dma_ops;
+	struct dma_domain	dma_domain;
+#endif
+};
+
+static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
+{
+	return container_of(bus->sysdata, struct vmd_dev, sysdata);
+}
+
+/*
+ * Drivers managing a device in a VMD domain allocate their own IRQs as before,
+ * but the MSI entry for the hardware it's driving will be programmed with a
+ * destination ID for the VMD MSI-X table.  The VMD muxes interrupts in its
+ * domain into one of its own, and the VMD driver de-muxes these for the
+ * handlers sharing that VMD IRQ.  The vmd irq_domain provides the operations
+ * and irq_chip to set this up.
+ */
+static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+	struct vmd_irq *vmdirq = data->chip_data;
+	struct vmd_irq_list *irq = vmdirq->irq;
+
+	msg->address_hi = MSI_ADDR_BASE_HI;
+	msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_DEST_ID(irq->index);
+	msg->data = 0;
+}
+
+/*
+ * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops.
+ */
+static void vmd_irq_enable(struct irq_data *data)
+{
+	struct vmd_irq *vmdirq = data->chip_data;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&list_lock, flags);
+	list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list);
+	raw_spin_unlock_irqrestore(&list_lock, flags);
+
+	data->chip->irq_unmask(data);
+}
+
+static void vmd_irq_disable(struct irq_data *data)
+{
+	struct vmd_irq *vmdirq = data->chip_data;
+	unsigned long flags;
+
+	data->chip->irq_mask(data);
+
+	raw_spin_lock_irqsave(&list_lock, flags);
+	list_del_rcu(&vmdirq->node);
+	INIT_LIST_HEAD_RCU(&vmdirq->node);
+	raw_spin_unlock_irqrestore(&list_lock, flags);
+}
+
+/*
+ * XXX: Stubbed until we develop acceptable way to not create conflicts with
+ * other devices sharing the same vector.
+ */
+static int vmd_irq_set_affinity(struct irq_data *data,
+				const struct cpumask *dest, bool force)
+{
+	return -EINVAL;
+}
+
+static struct irq_chip vmd_msi_controller = {
+	.name			= "VMD-MSI",
+	.irq_enable		= vmd_irq_enable,
+	.irq_disable		= vmd_irq_disable,
+	.irq_compose_msi_msg	= vmd_compose_msi_msg,
+	.irq_set_affinity	= vmd_irq_set_affinity,
+};
+
+static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
+				     msi_alloc_info_t *arg)
+{
+	return 0;
+}
+
+/*
+ * XXX: We can be even smarter selecting the best IRQ once we solve the
+ * affinity problem.
+ */
+static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
+{
+	int i, best = 1;
+	unsigned long flags;
+
+	if (!desc->msi_attrib.is_msix || vmd->msix_count == 1)
+		return &vmd->irqs[0];
+
+	raw_spin_lock_irqsave(&list_lock, flags);
+	for (i = 1; i < vmd->msix_count; i++)
+		if (vmd->irqs[i].count < vmd->irqs[best].count)
+			best = i;
+	vmd->irqs[best].count++;
+	raw_spin_unlock_irqrestore(&list_lock, flags);
+
+	return &vmd->irqs[best];
+}
+
+static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
+			unsigned int virq, irq_hw_number_t hwirq,
+			msi_alloc_info_t *arg)
+{
+	struct msi_desc *desc = arg->desc;
+	struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
+	struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
+
+	if (!vmdirq)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&vmdirq->node);
+	vmdirq->irq = vmd_next_irq(vmd, desc);
+	vmdirq->virq = virq;
+
+	irq_domain_set_info(domain, virq, vmdirq->irq->vmd_vector, info->chip,
+			    vmdirq, handle_untracked_irq, vmd, NULL);
+	return 0;
+}
+
+static void vmd_msi_free(struct irq_domain *domain,
+			struct msi_domain_info *info, unsigned int virq)
+{
+	struct vmd_irq *vmdirq = irq_get_chip_data(virq);
+	unsigned long flags;
+
+	/* XXX: Potential optimization to rebalance */
+	raw_spin_lock_irqsave(&list_lock, flags);
+	vmdirq->irq->count--;
+	raw_spin_unlock_irqrestore(&list_lock, flags);
+
+	kfree_rcu(vmdirq, rcu);
+}
+
+static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
+			   int nvec, msi_alloc_info_t *arg)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
+
+	if (nvec > vmd->msix_count)
+		return vmd->msix_count;
+
+	memset(arg, 0, sizeof(*arg));
+	return 0;
+}
+
+static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
+{
+	arg->desc = desc;
+}
+
+static struct msi_domain_ops vmd_msi_domain_ops = {
+	.get_hwirq	= vmd_get_hwirq,
+	.msi_init	= vmd_msi_init,
+	.msi_free	= vmd_msi_free,
+	.msi_prepare	= vmd_msi_prepare,
+	.set_desc	= vmd_set_desc,
+};
+
+static struct msi_domain_info vmd_msi_domain_info = {
+	.flags		= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+			  MSI_FLAG_PCI_MSIX,
+	.ops		= &vmd_msi_domain_ops,
+	.chip		= &vmd_msi_controller,
+};
+
+#ifdef CONFIG_X86_DEV_DMA_OPS
+/*
+ * VMD replaces the requester ID with its own.  DMA mappings for devices in a
+ * VMD domain need to be mapped for the VMD, not the device requiring
+ * the mapping.
+ */
+static struct device *to_vmd_dev(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct vmd_dev *vmd = vmd_from_bus(pdev->bus);
+
+	return &vmd->dev->dev;
+}
+
+static struct dma_map_ops *vmd_dma_ops(struct device *dev)
+{
+	return get_dma_ops(to_vmd_dev(dev));
+}
+
+static void *vmd_alloc(struct device *dev, size_t size, dma_addr_t *addr,
+		       gfp_t flag, unsigned long attrs)
+{
+	return vmd_dma_ops(dev)->alloc(to_vmd_dev(dev), size, addr, flag,
+				       attrs);
+}
+
+static void vmd_free(struct device *dev, size_t size, void *vaddr,
+		     dma_addr_t addr, unsigned long attrs)
+{
+	return vmd_dma_ops(dev)->free(to_vmd_dev(dev), size, vaddr, addr,
+				      attrs);
+}
+
+static int vmd_mmap(struct device *dev, struct vm_area_struct *vma,
+		    void *cpu_addr, dma_addr_t addr, size_t size,
+		    unsigned long attrs)
+{
+	return vmd_dma_ops(dev)->mmap(to_vmd_dev(dev), vma, cpu_addr, addr,
+				      size, attrs);
+}
+
+static int vmd_get_sgtable(struct device *dev, struct sg_table *sgt,
+			   void *cpu_addr, dma_addr_t addr, size_t size,
+			   unsigned long attrs)
+{
+	return vmd_dma_ops(dev)->get_sgtable(to_vmd_dev(dev), sgt, cpu_addr,
+					     addr, size, attrs);
+}
+
+static dma_addr_t vmd_map_page(struct device *dev, struct page *page,
+			       unsigned long offset, size_t size,
+			       enum dma_data_direction dir,
+			       unsigned long attrs)
+{
+	return vmd_dma_ops(dev)->map_page(to_vmd_dev(dev), page, offset, size,
+					  dir, attrs);
+}
+
+static void vmd_unmap_page(struct device *dev, dma_addr_t addr, size_t size,
+			   enum dma_data_direction dir, unsigned long attrs)
+{
+	vmd_dma_ops(dev)->unmap_page(to_vmd_dev(dev), addr, size, dir, attrs);
+}
+
+static int vmd_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+		      enum dma_data_direction dir, unsigned long attrs)
+{
+	return vmd_dma_ops(dev)->map_sg(to_vmd_dev(dev), sg, nents, dir, attrs);
+}
+
+static void vmd_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+			 enum dma_data_direction dir, unsigned long attrs)
+{
+	vmd_dma_ops(dev)->unmap_sg(to_vmd_dev(dev), sg, nents, dir, attrs);
+}
+
+static void vmd_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
+				    size_t size, enum dma_data_direction dir)
+{
+	vmd_dma_ops(dev)->sync_single_for_cpu(to_vmd_dev(dev), addr, size, dir);
+}
+
+static void vmd_sync_single_for_device(struct device *dev, dma_addr_t addr,
+				       size_t size, enum dma_data_direction dir)
+{
+	vmd_dma_ops(dev)->sync_single_for_device(to_vmd_dev(dev), addr, size,
+						 dir);
+}
+
+static void vmd_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+				int nents, enum dma_data_direction dir)
+{
+	vmd_dma_ops(dev)->sync_sg_for_cpu(to_vmd_dev(dev), sg, nents, dir);
+}
+
+static void vmd_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+				   int nents, enum dma_data_direction dir)
+{
+	vmd_dma_ops(dev)->sync_sg_for_device(to_vmd_dev(dev), sg, nents, dir);
+}
+
+static int vmd_mapping_error(struct device *dev, dma_addr_t addr)
+{
+	return vmd_dma_ops(dev)->mapping_error(to_vmd_dev(dev), addr);
+}
+
+static int vmd_dma_supported(struct device *dev, u64 mask)
+{
+	return vmd_dma_ops(dev)->dma_supported(to_vmd_dev(dev), mask);
+}
+
+#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
+static u64 vmd_get_required_mask(struct device *dev)
+{
+	return vmd_dma_ops(dev)->get_required_mask(to_vmd_dev(dev));
+}
+#endif
+
+static void vmd_teardown_dma_ops(struct vmd_dev *vmd)
+{
+	struct dma_domain *domain = &vmd->dma_domain;
+
+	if (get_dma_ops(&vmd->dev->dev))
+		del_dma_domain(domain);
+}
+
+#define ASSIGN_VMD_DMA_OPS(source, dest, fn)	\
+	do {					\
+		if (source->fn)			\
+			dest->fn = vmd_##fn;	\
+	} while (0)
+
+static void vmd_setup_dma_ops(struct vmd_dev *vmd)
+{
+	const struct dma_map_ops *source = get_dma_ops(&vmd->dev->dev);
+	struct dma_map_ops *dest = &vmd->dma_ops;
+	struct dma_domain *domain = &vmd->dma_domain;
+
+	domain->domain_nr = vmd->sysdata.domain;
+	domain->dma_ops = dest;
+
+	if (!source)
+		return;
+	ASSIGN_VMD_DMA_OPS(source, dest, alloc);
+	ASSIGN_VMD_DMA_OPS(source, dest, free);
+	ASSIGN_VMD_DMA_OPS(source, dest, mmap);
+	ASSIGN_VMD_DMA_OPS(source, dest, get_sgtable);
+	ASSIGN_VMD_DMA_OPS(source, dest, map_page);
+	ASSIGN_VMD_DMA_OPS(source, dest, unmap_page);
+	ASSIGN_VMD_DMA_OPS(source, dest, map_sg);
+	ASSIGN_VMD_DMA_OPS(source, dest, unmap_sg);
+	ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_cpu);
+	ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_device);
+	ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_cpu);
+	ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_device);
+	ASSIGN_VMD_DMA_OPS(source, dest, mapping_error);
+	ASSIGN_VMD_DMA_OPS(source, dest, dma_supported);
+#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
+	ASSIGN_VMD_DMA_OPS(source, dest, get_required_mask);
+#endif
+	add_dma_domain(domain);
+}
+#undef ASSIGN_VMD_DMA_OPS
+#else
+static void vmd_teardown_dma_ops(struct vmd_dev *vmd) {}
+static void vmd_setup_dma_ops(struct vmd_dev *vmd) {}
+#endif
+
+static char __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
+				  unsigned int devfn, int reg, int len)
+{
+	char __iomem *addr = vmd->cfgbar +
+			     (bus->number << 20) + (devfn << 12) + reg;
+
+	if ((addr - vmd->cfgbar) + len >=
+	    resource_size(&vmd->dev->resource[VMD_CFGBAR]))
+		return NULL;
+
+	return addr;
+}
+
+/*
+ * CPU may deadlock if config space is not serialized on some versions of this
+ * hardware, so all config space access is done under a spinlock.
+ */
+static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg,
+			int len, u32 *value)
+{
+	struct vmd_dev *vmd = vmd_from_bus(bus);
+	char __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
+	unsigned long flags;
+	int ret = 0;
+
+	if (!addr)
+		return -EFAULT;
+
+	spin_lock_irqsave(&vmd->cfg_lock, flags);
+	switch (len) {
+	case 1:
+		*value = readb(addr);
+		break;
+	case 2:
+		*value = readw(addr);
+		break;
+	case 4:
+		*value = readl(addr);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	spin_unlock_irqrestore(&vmd->cfg_lock, flags);
+	return ret;
+}
+
+/*
+ * VMD h/w converts non-posted config writes to posted memory writes. The
+ * read-back in this function forces the completion so it returns only after
+ * the config space was written, as expected.
+ */
+static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg,
+			 int len, u32 value)
+{
+	struct vmd_dev *vmd = vmd_from_bus(bus);
+	char __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len);
+	unsigned long flags;
+	int ret = 0;
+
+	if (!addr)
+		return -EFAULT;
+
+	spin_lock_irqsave(&vmd->cfg_lock, flags);
+	switch (len) {
+	case 1:
+		writeb(value, addr);
+		readb(addr);
+		break;
+	case 2:
+		writew(value, addr);
+		readw(addr);
+		break;
+	case 4:
+		writel(value, addr);
+		readl(addr);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	spin_unlock_irqrestore(&vmd->cfg_lock, flags);
+	return ret;
+}
+
+static struct pci_ops vmd_ops = {
+	.read		= vmd_pci_read,
+	.write		= vmd_pci_write,
+};
+
+static void vmd_attach_resources(struct vmd_dev *vmd)
+{
+	vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1];
+	vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2];
+}
+
+static void vmd_detach_resources(struct vmd_dev *vmd)
+{
+	vmd->dev->resource[VMD_MEMBAR1].child = NULL;
+	vmd->dev->resource[VMD_MEMBAR2].child = NULL;
+}
+
+/*
+ * VMD domains start at 0x1000 to not clash with ACPI _SEG domains.
+ */
+static int vmd_find_free_domain(void)
+{
+	int domain = 0xffff;
+	struct pci_bus *bus = NULL;
+
+	while ((bus = pci_find_next_bus(bus)) != NULL)
+		domain = max_t(int, domain, pci_domain_nr(bus));
+	return domain + 1;
+}
+
+static int vmd_enable_domain(struct vmd_dev *vmd)
+{
+	struct pci_sysdata *sd = &vmd->sysdata;
+	struct resource *res;
+	u32 upper_bits;
+	unsigned long flags;
+	LIST_HEAD(resources);
+
+	res = &vmd->dev->resource[VMD_CFGBAR];
+	vmd->resources[0] = (struct resource) {
+		.name  = "VMD CFGBAR",
+		.start = 0,
+		.end   = (resource_size(res) >> 20) - 1,
+		.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED,
+	};
+
+	/*
+	 * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can
+	 * put 32-bit resources in the window.
+	 *
+	 * There's no hardware reason why a 64-bit window *couldn't*
+	 * contain a 32-bit resource, but pbus_size_mem() computes the
+	 * bridge window size assuming a 64-bit window will contain no
+	 * 32-bit resources.  __pci_assign_resource() enforces that
+	 * artificial restriction to make sure everything will fit.
+	 *
+	 * The only way we could use a 64-bit non-prefechable MEMBAR is
+	 * if its address is <4GB so that we can convert it to a 32-bit
+	 * resource.  To be visible to the host OS, all VMD endpoints must
+	 * be initially configured by platform BIOS, which includes setting
+	 * up these resources.  We can assume the device is configured
+	 * according to the platform needs.
+	 */
+	res = &vmd->dev->resource[VMD_MEMBAR1];
+	upper_bits = upper_32_bits(res->end);
+	flags = res->flags & ~IORESOURCE_SIZEALIGN;
+	if (!upper_bits)
+		flags &= ~IORESOURCE_MEM_64;
+	vmd->resources[1] = (struct resource) {
+		.name  = "VMD MEMBAR1",
+		.start = res->start,
+		.end   = res->end,
+		.flags = flags,
+		.parent = res,
+	};
+
+	res = &vmd->dev->resource[VMD_MEMBAR2];
+	upper_bits = upper_32_bits(res->end);
+	flags = res->flags & ~IORESOURCE_SIZEALIGN;
+	if (!upper_bits)
+		flags &= ~IORESOURCE_MEM_64;
+	vmd->resources[2] = (struct resource) {
+		.name  = "VMD MEMBAR2",
+		.start = res->start + 0x2000,
+		.end   = res->end,
+		.flags = flags,
+		.parent = res,
+	};
+
+	sd->vmd_domain = true;
+	sd->domain = vmd_find_free_domain();
+	if (sd->domain < 0)
+		return sd->domain;
+
+	sd->node = pcibus_to_node(vmd->dev->bus);
+
+	vmd->irq_domain = pci_msi_create_irq_domain(NULL, &vmd_msi_domain_info,
+						    x86_vector_domain);
+	if (!vmd->irq_domain)
+		return -ENODEV;
+
+	pci_add_resource(&resources, &vmd->resources[0]);
+	pci_add_resource(&resources, &vmd->resources[1]);
+	pci_add_resource(&resources, &vmd->resources[2]);
+	vmd->bus = pci_create_root_bus(&vmd->dev->dev, 0, &vmd_ops, sd,
+				       &resources);
+	if (!vmd->bus) {
+		pci_free_resource_list(&resources);
+		irq_domain_remove(vmd->irq_domain);
+		return -ENODEV;
+	}
+
+	vmd_attach_resources(vmd);
+	vmd_setup_dma_ops(vmd);
+	dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain);
+	pci_rescan_bus(vmd->bus);
+
+	WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj,
+			       "domain"), "Can't create symlink to domain\n");
+	return 0;
+}
+
+static irqreturn_t vmd_irq(int irq, void *data)
+{
+	struct vmd_irq_list *irqs = data;
+	struct vmd_irq *vmdirq;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
+		generic_handle_irq(vmdirq->virq);
+	rcu_read_unlock();
+
+	return IRQ_HANDLED;
+}
+
+static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	struct vmd_dev *vmd;
+	int i, err;
+
+	if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
+		return -ENOMEM;
+
+	vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
+	if (!vmd)
+		return -ENOMEM;
+
+	vmd->dev = dev;
+	err = pcim_enable_device(dev);
+	if (err < 0)
+		return err;
+
+	vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
+	if (!vmd->cfgbar)
+		return -ENOMEM;
+
+	pci_set_master(dev);
+	if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
+	    dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32)))
+		return -ENODEV;
+
+	vmd->msix_count = pci_msix_vec_count(dev);
+	if (vmd->msix_count < 0)
+		return -ENODEV;
+
+	vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
+				 GFP_KERNEL);
+	if (!vmd->irqs)
+		return -ENOMEM;
+
+	vmd->msix_entries = devm_kcalloc(&dev->dev, vmd->msix_count,
+					 sizeof(*vmd->msix_entries),
+					 GFP_KERNEL);
+	if (!vmd->msix_entries)
+		return -ENOMEM;
+	for (i = 0; i < vmd->msix_count; i++)
+		vmd->msix_entries[i].entry = i;
+
+	vmd->msix_count = pci_enable_msix_range(vmd->dev, vmd->msix_entries, 1,
+						vmd->msix_count);
+	if (vmd->msix_count < 0)
+		return vmd->msix_count;
+
+	for (i = 0; i < vmd->msix_count; i++) {
+		INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
+		vmd->irqs[i].vmd_vector = vmd->msix_entries[i].vector;
+		vmd->irqs[i].index = i;
+
+		err = devm_request_irq(&dev->dev, vmd->irqs[i].vmd_vector,
+				       vmd_irq, 0, "vmd", &vmd->irqs[i]);
+		if (err)
+			return err;
+	}
+
+	spin_lock_init(&vmd->cfg_lock);
+	pci_set_drvdata(dev, vmd);
+	err = vmd_enable_domain(vmd);
+	if (err)
+		return err;
+
+	dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
+		 vmd->sysdata.domain);
+	return 0;
+}
+
+static void vmd_remove(struct pci_dev *dev)
+{
+	struct vmd_dev *vmd = pci_get_drvdata(dev);
+
+	vmd_detach_resources(vmd);
+	pci_set_drvdata(dev, NULL);
+	sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
+	pci_stop_root_bus(vmd->bus);
+	pci_remove_root_bus(vmd->bus);
+	vmd_teardown_dma_ops(vmd);
+	irq_domain_remove(vmd->irq_domain);
+}
+
+#ifdef CONFIG_PM
+static int vmd_suspend(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	pci_save_state(pdev);
+	return 0;
+}
+
+static int vmd_resume(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	pci_restore_state(pdev);
+	return 0;
+}
+#endif
+static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume);
+
+static const struct pci_device_id vmd_ids[] = {
+	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x201d),},
+	{0,}
+};
+MODULE_DEVICE_TABLE(pci, vmd_ids);
+
+static struct pci_driver vmd_drv = {
+	.name		= "vmd",
+	.id_table	= vmd_ids,
+	.probe		= vmd_probe,
+	.remove		= vmd_remove,
+	.driver		= {
+		.pm	= &vmd_dev_pm_ops,
+	},
+};
+module_pci_driver(vmd_drv);
+
+MODULE_AUTHOR("Intel Corporation");
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION("0.6");
-- 
2.7.2