diff --git a/hw/pc.h b/hw/pc.h
index feb8a7a..85662c3 100644
--- a/hw/pc.h
+++ b/hw/pc.h
@@ -176,6 +176,7 @@ struct PCII440FXState;
 typedef struct PCII440FXState PCII440FXState;
 
 PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix_devfn, qemu_irq *pic, ram_addr_t ram_size);
+PCIBus *i440fx_xen_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *pic, ram_addr_t ram_size);
 void i440fx_init_memory_mappings(PCII440FXState *d);
 
 /* piix4.c */
diff --git a/hw/pc_piix.c b/hw/pc_piix.c
index 8e5023e..b9b99d2 100644
--- a/hw/pc_piix.c
+++ b/hw/pc_piix.c
@@ -109,7 +109,11 @@ static void pc_init1(ram_addr_t ram_size,
     isa_irq = qemu_allocate_irqs(isa_irq_handler, isa_irq_state, 24);
 
     if (pci_enabled) {
-        pci_bus = i440fx_init(&i440fx_state, &piix3_devfn, isa_irq, ram_size);
+        if (!xen_enabled()) {
+            pci_bus = i440fx_init(&i440fx_state, &piix3_devfn, isa_irq, ram_size);
+        } else {
+            pci_bus = i440fx_xen_init(&i440fx_state, &piix3_devfn, isa_irq, ram_size);
+        }
     } else {
         pci_bus = NULL;
         i440fx_state = NULL;
diff --git a/hw/piix_pci.c b/hw/piix_pci.c
index 358da58..c11a7f6 100644
--- a/hw/piix_pci.c
+++ b/hw/piix_pci.c
@@ -29,6 +29,7 @@
 #include "isa.h"
 #include "sysbus.h"
 #include "range.h"
+#include "xen.h"
 
 /*
  * I440FX chipset data sheet.
@@ -151,6 +152,13 @@ static void i440fx_write_config(PCIDevice *dev,
     }
 }
 
+static void i440fx_write_config_xen(PCIDevice *dev,
+                                    uint32_t address, uint32_t val, int len)
+{
+    xen_piix_pci_write_config_client(address, val, len);
+    i440fx_write_config(dev, address, val, len);
+}
+
 static int i440fx_load_old(QEMUFile* f, void *opaque, int version_id)
 {
     PCII440FXState *d = opaque;
@@ -216,7 +224,10 @@ static int i440fx_initfn(PCIDevice *dev)
     return 0;
 }
 
-PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *pic, ram_addr_t ram_size)
+static PCIBus *i440fx_common_init(const char *device_name,
+                                  PCII440FXState **pi440fx_state,
+                                  int *piix3_devfn,
+                                  qemu_irq *pic, ram_addr_t ram_size)
 {
     DeviceState *dev;
     PCIBus *b;
@@ -230,13 +241,13 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *
     s->bus = b;
     qdev_init_nofail(dev);
 
-    d = pci_create_simple(b, 0, "i440FX");
+    d = pci_create_simple(b, 0, device_name);
     *pi440fx_state = DO_UPCAST(PCII440FXState, dev, d);
 
     piix3 = DO_UPCAST(PIIX3State, dev,
                       pci_create_simple_multifunction(b, -1, true, "PIIX3"));
     piix3->pic = pic;
-    pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, piix3, 4);
+
     (*pi440fx_state)->piix3 = piix3;
 
     *piix3_devfn = piix3->dev.devfn;
@@ -249,6 +260,28 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *
     return b;
 }
 
+PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn,
+                    qemu_irq *pic, ram_addr_t ram_size)
+{
+    PCIBus *b;
+
+    b = i440fx_common_init("i440FX", pi440fx_state, piix3_devfn, pic, ram_size);
+    pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, (*pi440fx_state)->piix3, 4);
+
+    return b;
+}
+
+PCIBus *i440fx_xen_init(PCII440FXState **pi440fx_state, int *piix3_devfn,
+                        qemu_irq *pic, ram_addr_t ram_size)
+{
+    PCIBus *b;
+
+    b = i440fx_common_init("i440FX-xen", pi440fx_state, piix3_devfn, pic, ram_size);
+    pci_bus_irqs(b, xen_piix3_set_irq, xen_pci_slot_get_pirq, (*pi440fx_state)->piix3, 4);
+
+    return b;
+}
+
 /* PIIX3 PCI to ISA bridge */
 
 static void piix3_set_irq(void *opaque, int irq_num, int level)
@@ -352,6 +385,14 @@ static PCIDeviceInfo i440fx_info[] = {
         .init         = i440fx_initfn,
         .config_write = i440fx_write_config,
     },{
+        .qdev.name    = "i440FX-xen",
+        .qdev.desc    = "Host bridge",
+        .qdev.size    = sizeof(PCII440FXState),
+        .qdev.vmsd    = &vmstate_i440fx,
+        .qdev.no_user = 1,
+        .init         = i440fx_initfn,
+        .config_write = i440fx_write_config_xen,
+    },{
         .qdev.name    = "PIIX3",
         .qdev.desc    = "ISA bridge",
         .qdev.size    = sizeof(PIIX3State),
diff --git a/hw/xen.h b/hw/xen.h
index 726360a..620827d 100644
--- a/hw/xen.h
+++ b/hw/xen.h
@@ -8,6 +8,8 @@
  */
 #include <inttypes.h>
 
+#include "qemu-common.h"
+
 /* xen-machine.c */
 enum xen_mode {
     XEN_EMULATE = 0,  // xen emulation, using xenner (default)
@@ -29,6 +31,10 @@ static inline int xen_enabled(void)
 #endif
 }
 
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num);
+void xen_piix3_set_irq(void *opaque, int irq_num, int level);
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len);
+
 int xen_init(void);
 
 #if defined(CONFIG_XEN) && CONFIG_XEN_CTRL_INTERFACE_VERSION < 400
diff --git a/xen-all.c b/xen-all.c
index e2872f9..0bc0978 100644
--- a/xen-all.c
+++ b/xen-all.c
@@ -6,9 +6,40 @@
  *
  */
 
+#include "hw/pci.h"
 #include "hw/xen_common.h"
 #include "hw/xen_backend.h"
 
+/* Xen specific function for piix pci */
+
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
+{
+    return irq_num + ((pci_dev->devfn >> 3) << 2);
+}
+
+void xen_piix3_set_irq(void *opaque, int irq_num, int level)
+{
+    xc_hvm_set_pci_intx_level(xen_xc, xen_domid, 0, 0, irq_num >> 2,
+                              irq_num & 3, level);
+}
+
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len)
+{
+    int i;
+
+    /* Scan for updates to PCI link routes (0x60-0x63). */
+    for (i = 0; i < len; i++) {
+        uint8_t v = (val >> (8 * i)) & 0xff;
+        if (v & 0x80) {
+            v = 0;
+        }
+        v &= 0xf;
+        if (((address + i) >= 0x60) && ((address + i) <= 0x63)) {
+            xc_hvm_set_pci_link_route(xen_xc, xen_domid, address + i - 0x60, v);
+        }
+    }
+}
+
 /* Initialise Xen */
 
 int xen_init(void)
diff --git a/xen-stub.c b/xen-stub.c
index beb982f..dc90f10 100644
--- a/xen-stub.c
+++ b/xen-stub.c
@@ -9,6 +9,19 @@
 #include "qemu-common.h"
 #include "hw/xen.h"
 
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
+{
+    return -1;
+}
+
+void xen_piix3_set_irq(void *opaque, int irq_num, int level)
+{
+}
+
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len)
+{
+}
+
 int xen_init(void)
 {
     return -ENOSYS;
