diff --git a/Makefile b/Makefile
index 47f5625..cee286a 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,7 @@ SRCBOTH=misc.c pmm.c stacks.c output.c util.c block.c floppy.c ata.c mouse.c \
         kbd.c pci.c serial.c clock.c pic.c cdrom.c ps2port.c smp.c resume.c \
         pnpbios.c pirtable.c vgahooks.c ramdisk.c pcibios.c blockcmd.c \
         usb.c usb-uhci.c usb-ohci.c usb-ehci.c usb-hid.c usb-msc.c \
-        virtio-ring.c virtio-pci.c virtio-blk.c
+        virtio-ring.c virtio-pci.c virtio-blk.c iommu.c
 SRC16=$(SRCBOTH) system.c disk.c apm.c font.c
 SRC32FLAT=$(SRCBOTH) post.c shadow.c memmap.c coreboot.c boot.c \
       acpi.c smm.c mptable.c smbios.c pciinit.c optionroms.c mtrr.c \
diff --git a/src/iommu.c b/src/iommu.c
new file mode 100644
index 0000000..4ff62fc
--- /dev/null
+++ b/src/iommu.c
@@ -0,0 +1,63 @@
+// AMD IOMMU initialization code.
+//
+// Copyright (C) 2010  Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "iommu.h"
+#include "pci.h"
+#include "types.h"
+
+#define IOMMU_CAP_BAR_LOW       0x04
+#define IOMMU_CAP_BAR_HIGH      0x08
+#define IOMMU_CAP_RANGE         0x0C
+#define IOMMU_CAP_MISC          0x10
+
+static int iommu_bdf = -1;
+static u8 iommu_cap_offset;
+static u32 iommu_base;
+
+void iommu_init(int bdf, u32 base)
+{
+    u8 ptr, cap, type;
+
+    /* Only one IOMMU is supported. */
+    if (iommu_bdf >= 0)
+        return;
+
+    foreachcap(bdf, ptr, cap) {
+        type = pci_config_readb(bdf, cap);
+        if (type == PCI_CAP_ID_SEC)
+            break;
+    }
+    if (!cap)
+        return;
+
+    pci_config_writel(bdf, cap + IOMMU_CAP_RANGE, 0);
+    pci_config_writel(bdf, cap + IOMMU_CAP_BAR_HIGH, 0);
+    pci_config_writel(bdf, cap + IOMMU_CAP_BAR_LOW, base | 1);
+
+    iommu_bdf = bdf;
+    iommu_cap_offset = cap;
+    iommu_base = base;
+}
+
+int iommu_get_bdf(void)
+{
+    return iommu_bdf;
+}
+
+u8 iommu_get_cap_offset(void)
+{
+    return iommu_cap_offset;
+}
+
+u32 iommu_get_misc(void)
+{
+    return pci_config_readw(iommu_bdf, iommu_cap_offset + IOMMU_CAP_MISC + 2);
+}
+
+u32 iommu_get_base(void)
+{
+    return iommu_base;
+}
diff --git a/src/iommu.h b/src/iommu.h
new file mode 100644
index 0000000..27ae2c7
--- /dev/null
+++ b/src/iommu.h
@@ -0,0 +1,12 @@
+#ifndef __IOMMU_H
+#define __IOMMU_H
+
+#include "types.h"
+
+void iommu_init(int bdf, u32 base);
+int iommu_get_bdf(void);
+u8 iommu_get_cap_offset(void);
+u32 iommu_get_misc(void);
+u32 iommu_get_base(void);
+
+#endif // __IOMMU_H
diff --git a/src/pci_ids.h b/src/pci_ids.h
index 441c086..6876fbe 100644
--- a/src/pci_ids.h
+++ b/src/pci_ids.h
@@ -72,6 +72,7 @@
 #define PCI_CLASS_SYSTEM_RTC            0x0803
 #define PCI_CLASS_SYSTEM_PCI_HOTPLUG    0x0804
 #define PCI_CLASS_SYSTEM_SDHCI          0x0805
+#define PCI_CLASS_SYSTEM_IOMMU          0x0806
 #define PCI_CLASS_SYSTEM_OTHER          0x0880
 
 #define PCI_BASE_CLASS_INPUT            0x09
diff --git a/src/pci_regs.h b/src/pci_regs.h
index e6180ce..46b048f 100644
--- a/src/pci_regs.h
+++ b/src/pci_regs.h
@@ -208,6 +208,7 @@
 #define  PCI_CAP_ID_SHPC        0x0C    /* PCI Standard Hot-Plug Controller */
 #define  PCI_CAP_ID_SSVID       0x0D    /* Bridge subsystem vendor/device ID */
 #define  PCI_CAP_ID_AGP3        0x0E    /* AGP Target PCI-PCI bridge */
+#define  PCI_CAP_ID_SEC         0x0F    /* Secure Device (AMD IOMMU) */
 #define  PCI_CAP_ID_EXP         0x10    /* PCI Express */
 #define  PCI_CAP_ID_MSIX        0x11    /* MSI-X */
 #define PCI_CAP_LIST_NEXT       1       /* Next capability in the list */
diff --git a/src/pciinit.c b/src/pciinit.c
index f75e552..7cb67c6 100644
--- a/src/pciinit.c
+++ b/src/pciinit.c
@@ -11,6 +11,7 @@
 #include "pci_ids.h" // PCI_VENDOR_ID_INTEL
 #include "pci_regs.h" // PCI_COMMAND
 #include "dev-i440fx.h"
+#include "iommu.h"
 
 #define PCI_ROM_SLOT 6
 #define PCI_NUM_REGIONS 7
@@ -262,6 +263,16 @@ static void apple_macio_init(u16 bdf, void *arg)
     pci_set_io_region_addr(bdf, 0, 0x80800000);
 }
 
+static void pci_bios_init_iommu(u16 bdf, void *arg)
+{
+    u32 base;
+
+    base = ALIGN(pci_bios_mem_addr, 0x4000);
+    pci_bios_mem_addr += 0x4000;
+
+    iommu_init(bdf, base);
+}
+
 static const struct pci_device_id pci_class_tbl[] = {
     /* STORAGE IDE */
     PCI_DEVICE_CLASS(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371SB_1,
@@ -285,6 +296,10 @@ static const struct pci_device_id pci_class_tbl[] = {
     PCI_DEVICE_CLASS(PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_BRIDGE_PCI,
                      pci_bios_init_device_bridge),
 
+    /* AMD IOMMU */
+    PCI_DEVICE_CLASS(PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_SYSTEM_IOMMU,
+                     pci_bios_init_iommu),
+
     /* default */
     PCI_DEVICE(PCI_ANY_ID, PCI_ANY_ID, pci_bios_allocate_regions),
 
