diff --git a/Makefile b/Makefile
index fe0c1ce..98f253d 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,7 @@ OUT=out/
 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
+        usb.c usb-uhci.c usb-ohci.c usb-ehci.c usb-hid.c usb-msc.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/acpi.c b/src/acpi.c
index 0559443..7ea9c55 100644
--- a/src/acpi.c
+++ b/src/acpi.c
@@ -6,6 +6,7 @@
 // This file may be distributed under the terms of the GNU LGPLv3 license.
 
 #include "acpi.h" // struct rsdp_descriptor
+#include "iommu.h"
 #include "util.h" // memcpy
 #include "pci.h" // pci_find_device
 #include "biosvar.h" // GET_EBDA
@@ -268,6 +269,36 @@ struct srat_memory_affinity
     u32    reserved3[2];
 } PACKED;
 
+/*
+ * IVRS (I/O Virtualization Reporting Structure) table.
+ *
+ * Describes the AMD IOMMU, as per:
+ * "AMD I/O Virtualization Technology (IOMMU) Specification", rev 1.26
+ */
+
+struct ivrs_ivhd
+{
+    u8    type;
+    u8    flags;
+    u16   length;
+    u16   devid;
+    u16   capab_off;
+    u32   iommu_base_low;
+    u32   iommu_base_high;
+    u16   pci_seg_group;
+    u16   iommu_info;
+    u32   reserved;
+    u8    entry[0];
+} PACKED;
+
+struct ivrs_table
+{
+    ACPI_TABLE_HEADER_DEF    /* ACPI common table header. */
+    u32                iv_info;
+    u32                reserved[2];
+    struct ivrs_ivhd   ivhd;
+} PACKED;
+
 #include "acpi-dsdt.hex"
 
 static inline u16 cpu_to_le16(u16 x)
@@ -599,6 +630,53 @@ build_srat(void)
     return srat;
 }
 
+#define IVRS_SIGNATURE 0x53525649 // IVRS
+#define IVRS_MAX_DEVS  32
+static void *
+build_ivrs(void)
+{
+    int iommu_bdf, bdf, max, i;
+    struct ivrs_table *ivrs;
+    struct ivrs_ivhd *ivhd;
+
+    iommu_bdf = pci_find_class(PCI_CLASS_SYSTEM_IOMMU);
+    if (iommu_bdf < 0)
+        return NULL;
+
+    ivrs = malloc_high(sizeof(struct ivrs_table) + 4 * IVRS_MAX_DEVS);
+    ivrs->iv_info = iommu_get_misc() & ~0x000F;
+
+    ivhd = &ivrs->ivhd;
+    ivhd->type              = 0x10;
+    ivhd->flags             = 0;
+    ivhd->length            = sizeof(struct ivrs_ivhd);
+    ivhd->devid             = iommu_get_bdf();
+    ivhd->capab_off         = iommu_get_cap_offset();
+    ivhd->iommu_base_low    = iommu_get_base();
+    ivhd->iommu_base_high   = 0;
+    ivhd->pci_seg_group     = 0;
+    ivhd->iommu_info        = 0;
+    ivhd->reserved          = 0;
+
+    i = 0;
+    foreachpci(bdf, max) {
+        if (bdf == ivhd->devid)
+            continue;
+        ivhd->entry[4 * i + 0] = 2;
+        ivhd->entry[4 * i + 1] = bdf & 0xFF;
+        ivhd->entry[4 * i + 2] = (bdf >> 8) & 0xFF;
+        ivhd->entry[4 * i + 3] = ~(1 << 3);
+        ivhd->length += 4;
+        if (++i >= IVRS_MAX_DEVS)
+            break;
+    }
+
+    build_header((void *) ivrs, IVRS_SIGNATURE,
+                 sizeof(struct ivrs_table) + 4 * i, 1);
+
+    return ivrs;
+}
+
 struct rsdp_descriptor *RsdpAddr;
 
 #define MAX_ACPI_TABLES 20
@@ -639,6 +717,7 @@ acpi_bios_init(void)
     ACPI_INIT_TABLE(build_madt());
     ACPI_INIT_TABLE(build_hpet());
     ACPI_INIT_TABLE(build_srat());
+    ACPI_INIT_TABLE(build_ivrs());
 
     u16 i, external_tables = qemu_cfg_acpi_additional_tables();
 
diff --git a/src/iommu.c b/src/iommu.c
new file mode 100644
index 0000000..97af24a
--- /dev/null
+++ b/src/iommu.c
@@ -0,0 +1,64 @@
+// 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..105af25
--- /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);
+
+#endif
+
diff --git a/src/pci.h b/src/pci.h
index eea5b09..3f38a0e 100644
--- a/src/pci.h
+++ b/src/pci.h
@@ -39,6 +39,10 @@ int pci_next(int bdf, int *pmax);
     for (MAX=0x0100, BDF=pci_next(0, &MAX)      \
          ; BDF >= 0                             \
          ; BDF=pci_next(BDF+1, &MAX))
+#define foreachcap(BDF, PTR, CAP)                                         \
+    for (PTR = PCI_CAPABILITY_LIST, CAP = pci_config_readb(BDF, PTR);     \
+         CAP;                                                             \
+         PTR = CAP + PCI_CAP_LIST_NEXT, CAP = pci_config_readb(BDF, PTR))
 
 // pirtable.c
 void create_pirtable(void);
diff --git a/src/pci_ids.h b/src/pci_ids.h
index 1800f1d..3c695b2 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 e5effd4..600df4d 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 bfc669f..cad9114 100644
--- a/src/pciinit.c
+++ b/src/pciinit.c
@@ -85,6 +85,14 @@ static inline u32 pci_bios_alloc(u32 *region, u32 size)
     return ret;
 }
 
+static void pci_bios_init_iommu(u16 bdf)
+{
+    u32 base;
+
+    base = pci_bios_alloc(&pci_bios_mem_addr, 0x4000);
+    iommu_init(bdf, base);
+}
+
 static void pci_bios_init_device(u16 bdf)
 {
     int class;
@@ -130,6 +138,9 @@ static void pci_bios_init_device(u16 bdf)
             pci_set_io_region_addr(bdf, 0, 0x80800000);
         }
         break;
+    case PCI_CLASS_SYSTEM_IOMMU:
+        pci_bios_init_iommu(bdf);
+        break;
     default:
     default_map:
         /* default memory mappings */
