diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index f567965..265fa88 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -185,6 +185,8 @@
 }
 
 #ifdef CONFIG_XEN_DOM0
+static bool __read_mostly pci_seg_supported = true;
+
 static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
 	int ret = 0;
@@ -202,10 +204,11 @@
 
 		memset(&map_irq, 0, sizeof(map_irq));
 		map_irq.domid = domid;
-		map_irq.type = MAP_PIRQ_TYPE_MSI;
+		map_irq.type = MAP_PIRQ_TYPE_MSI_SEG;
 		map_irq.index = -1;
 		map_irq.pirq = -1;
-		map_irq.bus = dev->bus->number;
+		map_irq.bus = dev->bus->number |
+			      (pci_domain_nr(dev->bus) << 16);
 		map_irq.devfn = dev->devfn;
 
 		if (type == PCI_CAP_ID_MSIX) {
@@ -222,7 +225,20 @@
 			map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
 		}
 
-		ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+		ret = -EINVAL;
+		if (pci_seg_supported)
+			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
+						    &map_irq);
+		if (ret == -EINVAL && !pci_domain_nr(dev->bus)) {
+			map_irq.type = MAP_PIRQ_TYPE_MSI;
+			map_irq.index = -1;
+			map_irq.pirq = -1;
+			map_irq.bus = dev->bus->number;
+			ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq,
+						    &map_irq);
+			if (ret != -EINVAL)
+				pci_seg_supported = false;
+		}
 		if (ret) {
 			dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n",
 				 ret, domid);
diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
index 02c402b..6605707 100644
--- a/drivers/xen/pci.c
+++ b/drivers/xen/pci.c
@@ -18,6 +18,7 @@
  */
 
 #include <linux/pci.h>
+#include <linux/acpi.h>
 #include <xen/xen.h>
 #include <xen/interface/physdev.h>
 #include <xen/interface/xen.h>
@@ -26,26 +27,85 @@
 #include <asm/xen/hypercall.h>
 #include "../pci/pci.h"
 
+static bool __read_mostly pci_seg_supported = true;
+
 static int xen_add_device(struct device *dev)
 {
 	int r;
 	struct pci_dev *pci_dev = to_pci_dev(dev);
+#ifdef CONFIG_PCI_IOV
+	struct pci_dev *physfn = pci_dev->physfn;
+#endif
+
+	if (pci_seg_supported) {
+		struct physdev_pci_device_add add = {
+			.seg = pci_domain_nr(pci_dev->bus),
+			.bus = pci_dev->bus->number,
+			.devfn = pci_dev->devfn
+		};
+#ifdef CONFIG_ACPI
+		acpi_handle handle;
+#endif
 
 #ifdef CONFIG_PCI_IOV
-	if (pci_dev->is_virtfn) {
+		if (pci_dev->is_virtfn) {
+			add.flags = XEN_PCI_DEV_VIRTFN;
+			add.physfn.bus = physfn->bus->number;
+			add.physfn.devfn = physfn->devfn;
+		} else
+#endif
+		if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
+			add.flags = XEN_PCI_DEV_EXTFN;
+
+#ifdef CONFIG_ACPI
+		handle = DEVICE_ACPI_HANDLE(&pci_dev->dev);
+		if (!handle)
+			handle = DEVICE_ACPI_HANDLE(pci_dev->bus->bridge);
+#ifdef CONFIG_PCI_IOV
+		if (!handle && pci_dev->is_virtfn)
+			handle = DEVICE_ACPI_HANDLE(physfn->bus->bridge);
+#endif
+		if (handle) {
+			acpi_status status;
+
+			do {
+				unsigned long long pxm;
+
+				status = acpi_evaluate_integer(handle, "_PXM",
+							       NULL, &pxm);
+				if (ACPI_SUCCESS(status)) {
+					add.optarr[0] = pxm;
+					add.flags |= XEN_PCI_DEV_PXM;
+					break;
+				}
+				status = acpi_get_parent(handle, &handle);
+			} while (ACPI_SUCCESS(status));
+		}
+#endif /* CONFIG_ACPI */
+
+		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
+		if (r != -ENOSYS)
+			return r;
+		pci_seg_supported = false;
+	}
+
+	if (pci_domain_nr(pci_dev->bus))
+		r = -ENOSYS;
+#ifdef CONFIG_PCI_IOV
+	else if (pci_dev->is_virtfn) {
 		struct physdev_manage_pci_ext manage_pci_ext = {
 			.bus		= pci_dev->bus->number,
 			.devfn		= pci_dev->devfn,
 			.is_virtfn 	= 1,
-			.physfn.bus	= pci_dev->physfn->bus->number,
-			.physfn.devfn	= pci_dev->physfn->devfn,
+			.physfn.bus	= physfn->bus->number,
+			.physfn.devfn	= physfn->devfn,
 		};
 
 		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 			&manage_pci_ext);
-	} else
+	}
 #endif
-	if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
+	else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
 		struct physdev_manage_pci_ext manage_pci_ext = {
 			.bus		= pci_dev->bus->number,
 			.devfn		= pci_dev->devfn,
@@ -71,13 +131,27 @@
 {
 	int r;
 	struct pci_dev *pci_dev = to_pci_dev(dev);
-	struct physdev_manage_pci manage_pci;
 
-	manage_pci.bus = pci_dev->bus->number;
-	manage_pci.devfn = pci_dev->devfn;
+	if (pci_seg_supported) {
+		struct physdev_pci_device device = {
+			.seg = pci_domain_nr(pci_dev->bus),
+			.bus = pci_dev->bus->number,
+			.devfn = pci_dev->devfn
+		};
 
-	r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
-		&manage_pci);
+		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
+					  &device);
+	} else if (pci_domain_nr(pci_dev->bus))
+		r = -ENOSYS;
+	else {
+		struct physdev_manage_pci manage_pci = {
+			.bus = pci_dev->bus->number,
+			.devfn = pci_dev->devfn
+		};
+
+		r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
+					  &manage_pci);
+	}
 
 	return r;
 }
diff --git a/include/xen/interface/physdev.h b/include/xen/interface/physdev.h
index 534cac8..c1080d9 100644
--- a/include/xen/interface/physdev.h
+++ b/include/xen/interface/physdev.h
@@ -109,6 +109,7 @@
 #define MAP_PIRQ_TYPE_MSI		0x0
 #define MAP_PIRQ_TYPE_GSI		0x1
 #define MAP_PIRQ_TYPE_UNKNOWN		0x2
+#define MAP_PIRQ_TYPE_MSI_SEG		0x3
 
 #define PHYSDEVOP_map_pirq		13
 struct physdev_map_pirq {
@@ -119,7 +120,7 @@
     int index;
     /* IN or OUT */
     int pirq;
-    /* IN */
+    /* IN - high 16 bits hold segment for MAP_PIRQ_TYPE_MSI_SEG */
     int bus;
     /* IN */
     int devfn;
@@ -198,6 +199,37 @@
     uint32_t pirq;
 };
 
+#define XEN_PCI_DEV_EXTFN              0x1
+#define XEN_PCI_DEV_VIRTFN             0x2
+#define XEN_PCI_DEV_PXM                0x4
+
+#define PHYSDEVOP_pci_device_add        25
+struct physdev_pci_device_add {
+    /* IN */
+    uint16_t seg;
+    uint8_t bus;
+    uint8_t devfn;
+    uint32_t flags;
+    struct {
+        uint8_t bus;
+        uint8_t devfn;
+    } physfn;
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
+    uint32_t optarr[];
+#elif defined(__GNUC__)
+    uint32_t optarr[0];
+#endif
+};
+
+#define PHYSDEVOP_pci_device_remove     26
+#define PHYSDEVOP_restore_msi_ext       27
+struct physdev_pci_device {
+    /* IN */
+    uint16_t seg;
+    uint8_t bus;
+    uint8_t devfn;
+};
+
 /*
  * Notify that some PIRQ-bound event channels have been unmasked.
  * ** This command is obsolete since interface version 0x00030202 and is **