diff --git a/tools/firmware/hvmloader/acpi/acpi2_0.h b/tools/firmware/hvmloader/acpi/acpi2_0.h
index 78eb43d..ddcee74 100644
--- a/tools/firmware/hvmloader/acpi/acpi2_0.h
+++ b/tools/firmware/hvmloader/acpi/acpi2_0.h
@@ -449,17 +449,6 @@ struct acpi_20_slit {
 #define ACPI_2_0_SRAT_REVISION 0x01
 #define ACPI_2_0_SLIT_REVISION 0x01
 
-#pragma pack ()
-
-struct acpi_config {
-    unsigned char *dsdt_anycpu;
-    int dsdt_anycpu_len;
-    unsigned char *dsdt_15cpu;
-    int dsdt_15cpu_len;
-};
-
-void acpi_build_tables(struct acpi_config *config, unsigned int physical);
-
 #endif /* _ACPI_2_0_H_ */
 
 /*
diff --git a/tools/firmware/hvmloader/acpi/build.c b/tools/firmware/hvmloader/acpi/build.c
index 1f7103e..1092b4e 100644
--- a/tools/firmware/hvmloader/acpi/build.c
+++ b/tools/firmware/hvmloader/acpi/build.c
@@ -16,6 +16,7 @@
  */
 
 #include "acpi2_0.h"
+#include "libacpi.h"
 #include "ssdt_s3.h"
 #include "ssdt_s4.h"
 #include "ssdt_tpm.h"
@@ -38,24 +39,6 @@ extern struct acpi_20_fadt Fadt;
 extern struct acpi_20_facs Facs;
 extern struct acpi_20_waet Waet;
 
-/*
- * Located at ACPI_INFO_PHYSICAL_ADDRESS.
- *
- * This must match the Field("BIOS"....) definition in the DSDT.
- */
-struct acpi_info {
-    uint8_t  com1_present:1;    /* 0[0] - System has COM1? */
-    uint8_t  com2_present:1;    /* 0[1] - System has COM2? */
-    uint8_t  lpt1_present:1;    /* 0[2] - System has LPT1? */
-    uint8_t  hpet_present:1;    /* 0[3] - System has HPET? */
-    uint16_t nr_cpus;           /* 2    - Number of CPUs */
-    uint32_t pci_min, pci_len;  /* 4, 8 - PCI I/O hole boundaries */
-    uint32_t madt_csum_addr;    /* 12   - Address of MADT checksum */
-    uint32_t madt_lapic0_addr;  /* 16   - Address of first MADT LAPIC struct */
-    uint32_t vm_gid_addr;       /* 20   - Address of VM generation id buffer */
-    uint64_t pci_hi_min, pci_hi_len; /* 24, 32 - PCI I/O hole boundaries */
-};
-
 static void set_checksum(
     void *table, uint32_t checksum_offset, uint32_t length)
 {
@@ -358,7 +341,7 @@ static int construct_secondary_tables(unsigned long *table_ptrs,
     }
 
     /* HPET. */
-    if ( hpet_exists(ACPI_HPET_ADDRESS) )
+    if ( info->hpet_present )
     {
         hpet = construct_hpet();
         if (!hpet) return -1;
@@ -493,9 +476,8 @@ static int new_vm_gid(struct acpi_info *acpi_info)
     return 1;
 }
 
-void acpi_build_tables(struct acpi_config *config, unsigned int physical)
+void acpi_build_tables(struct acpi_config *config)
 {
-    struct acpi_info *acpi_info;
     struct acpi_20_rsdp *rsdp;
     struct acpi_20_rsdt *rsdt;
     struct acpi_20_xsdt *xsdt;
@@ -506,11 +488,6 @@ void acpi_build_tables(struct acpi_config *config, unsigned int physical)
     unsigned long        secondary_tables[ACPI_MAX_SECONDARY_TABLES];
     int                  nr_secondaries, i;
 
-    /* Allocate and initialise the acpi info area. */
-    mem_hole_populate_ram(ACPI_INFO_PHYSICAL_ADDRESS >> PAGE_SHIFT, 1);
-    acpi_info = (struct acpi_info *)ACPI_INFO_PHYSICAL_ADDRESS;
-    memset(acpi_info, 0, sizeof(*acpi_info));
-
     /*
      * Fill in high-memory data structures, starting at @buf.
      */
@@ -570,7 +547,8 @@ void acpi_build_tables(struct acpi_config *config, unsigned int physical)
                  offsetof(struct acpi_header, checksum),
                  sizeof(struct acpi_20_fadt));
 
-    nr_secondaries = construct_secondary_tables(secondary_tables, acpi_info);
+    nr_secondaries = construct_secondary_tables(secondary_tables,
+                                                &config->ainfo);
     if ( nr_secondaries < 0 )
         goto oom;
 
@@ -603,7 +581,7 @@ void acpi_build_tables(struct acpi_config *config, unsigned int physical)
     /*
      * Fill in low-memory data structures: acpi_info and RSDP.
      */
-    rsdp = (struct acpi_20_rsdp *)physical;
+    rsdp = (struct acpi_20_rsdp *)config->rsdp;
 
     memcpy(rsdp, &Rsdp, sizeof(struct acpi_20_rsdp));
     rsdp->rsdt_address = (unsigned long)rsdt;
@@ -615,20 +593,10 @@ void acpi_build_tables(struct acpi_config *config, unsigned int physical)
                  offsetof(struct acpi_20_rsdp, extended_checksum),
                  sizeof(struct acpi_20_rsdp));
 
-    if ( !new_vm_gid(acpi_info) )
+    if ( !new_vm_gid(&config->ainfo) )
         goto oom;
 
-    acpi_info->com1_present = uart_exists(0x3f8);
-    acpi_info->com2_present = uart_exists(0x2f8);
-    acpi_info->lpt1_present = lpt_exists(0x378);
-    acpi_info->hpet_present = hpet_exists(ACPI_HPET_ADDRESS);
-    acpi_info->pci_min = pci_mem_start;
-    acpi_info->pci_len = pci_mem_end - pci_mem_start;
-    if ( pci_hi_mem_end > pci_hi_mem_start )
-    {
-        acpi_info->pci_hi_min = pci_hi_mem_start;
-        acpi_info->pci_hi_len = pci_hi_mem_end - pci_hi_mem_start;
-    }
+    *(struct acpi_info *)config->ainfop = config->ainfo;
 
     return;
 
diff --git a/tools/firmware/hvmloader/acpi/libacpi.h b/tools/firmware/hvmloader/acpi/libacpi.h
new file mode 100644
index 0000000..098eee1
--- /dev/null
+++ b/tools/firmware/hvmloader/acpi/libacpi.h
@@ -0,0 +1,80 @@
+/******************************************************************************
+ * libacpi.h
+ * 
+ * libacpi interfaces
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (c) 2016 Oracle and/or its affiliates. All rights reserved.
+ */
+
+
+#ifndef __LIBACPI_H__
+#define __LIBACPI_H__
+
+#pragma pack ()
+
+/*
+ * This must match the Field("BIOS"....) definition in the DSDT.
+ */
+struct acpi_info {
+    uint8_t  com1_present:1;    /* 0[0] - System has COM1? */
+    uint8_t  com2_present:1;    /* 0[1] - System has COM2? */
+    uint8_t  lpt1_present:1;    /* 0[2] - System has LPT1? */
+    uint8_t  hpet_present:1;    /* 0[3] - System has HPET? */
+    uint16_t nr_cpus;           /* 2    - Number of CPUs */
+    uint32_t pci_min, pci_len;  /* 4, 8 - PCI I/O hole boundaries */
+    uint32_t madt_csum_addr;    /* 12   - Address of MADT checksum */
+    uint32_t madt_lapic0_addr;  /* 16   - Address of first MADT LAPIC struct */
+    uint32_t vm_gid_addr;       /* 20   - Address of VM generation id buffer */
+    uint64_t pci_hi_min, pci_hi_len; /* 24, 32 - PCI I/O hole boundaries */
+};
+
+struct acpi_config {
+    const unsigned char *dsdt_anycpu;
+    unsigned int dsdt_anycpu_len;
+    const unsigned char *dsdt_15cpu;
+    unsigned int dsdt_15cpu_len;
+
+    /* May have some fields updated by acpi_build_table() */
+    struct acpi_info ainfo;
+    /*
+     * Address where acpi_info should be placed.
+     * This must match the OperationRegion(BIOS, SystemMemory, ....)
+     * definition in the DSDT
+     */
+    unsigned int ainfop;
+
+    /* RSDP address */
+    unsigned int rsdp;
+};
+
+void acpi_build_tables(struct acpi_config *config);
+
+#endif /* __LIBACPI_H__ */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/firmware/hvmloader/seabios.c b/tools/firmware/hvmloader/seabios.c
index 9f66a79..2fbc3af 100644
--- a/tools/firmware/hvmloader/seabios.c
+++ b/tools/firmware/hvmloader/seabios.c
@@ -26,6 +26,7 @@
 
 #include "smbios_types.h"
 #include "acpi/acpi2_0.h"
+#include "acpi/libacpi.h"
 
 #define ROM_INCLUDE_SEABIOS
 #include "roms.inc"
diff --git a/tools/firmware/hvmloader/util.c b/tools/firmware/hvmloader/util.c
index 9af29b1..4293efa 100644
--- a/tools/firmware/hvmloader/util.c
+++ b/tools/firmware/hvmloader/util.c
@@ -22,6 +22,7 @@
 #include "hypercall.h"
 #include "ctype.h"
 #include "acpi/acpi2_0.h"
+#include "acpi/libacpi.h"
 #include <stdint.h>
 #include <xen/xen.h>
 #include <xen/memory.h>
@@ -860,7 +861,25 @@ int hpet_exists(unsigned long hpet_base)
 void hvmloader_acpi_build_tables(struct acpi_config *config,
                                  unsigned int physical)
 {
-    acpi_build_tables(config, physical);
+    /* Allocate and initialise the acpi info area. */
+    mem_hole_populate_ram(ACPI_INFO_PHYSICAL_ADDRESS >> PAGE_SHIFT, 1);
+
+    config->ainfo.com1_present = uart_exists(0x3f8);
+    config->ainfo.com2_present = uart_exists(0x2f8);
+    config->ainfo.lpt1_present = lpt_exists(0x378);
+    config->ainfo.hpet_present = hpet_exists(ACPI_HPET_ADDRESS);
+    config->ainfo.pci_min = pci_mem_start;
+    config->ainfo.pci_len = pci_mem_end - pci_mem_start;
+    if ( pci_hi_mem_end > pci_hi_mem_start )
+    {
+        config->ainfo.pci_hi_min = pci_hi_mem_start;
+        config->ainfo.pci_hi_len = pci_hi_mem_end - pci_hi_mem_start;
+    }
+
+    config->rsdp = physical;
+    config->ainfop = ACPI_INFO_PHYSICAL_ADDRESS;
+
+    acpi_build_tables(config);
 }
 
 /*
