diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index 6c90b1b..7504780 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -87,13 +87,13 @@ prelink-efi_lto.o: $(ALL_OBJS) efi/runtime.o efi/compat.o
 prelink.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink_lto.o
 	$(LD) $(LDFLAGS) -r -o $@ $^
 
-prelink-efi.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink-efi_lto.o efi/boot.init.o
+prelink-efi.o: $(patsubst %/built_in.o,%/built_in_bin.o,$(ALL_OBJS)) prelink-efi_lto.o efi/boot.init.o efi/efi-shared.o
 	$(guard) $(LD) $(LDFLAGS) -r -o $@ $^
 else
 prelink.o: $(ALL_OBJS)
 	$(LD) $(LDFLAGS) -r -o $@ $^
 
-prelink-efi.o: $(ALL_OBJS) efi/boot.init.o efi/runtime.o efi/compat.o
+prelink-efi.o: $(ALL_OBJS) efi/boot.init.o efi/runtime.o efi/compat.o efi/efi-shared.o
 	$(guard) $(LD) $(LDFLAGS) -r -o $@ $(filter-out %/efi/built_in.o,$^)
 endif
 
diff --git a/xen/arch/x86/efi/Makefile b/xen/arch/x86/efi/Makefile
index 1daa7ac..9c198d2 100644
--- a/xen/arch/x86/efi/Makefile
+++ b/xen/arch/x86/efi/Makefile
@@ -9,6 +9,6 @@ efi := $(if $(efi),$(shell $(CC) $(filter-out $(CFLAGS-y) .%.d,$(CFLAGS)) -c che
 efi := $(if $(efi),$(shell $(LD) -mi386pep --subsystem=10 -o check.efi check.o 2>disabled && echo y))
 efi := $(if $(efi),$(shell rm disabled)y,$(shell $(call create,boot.init.o); $(call create,runtime.o)))
 
-extra-$(efi) += boot.init.o relocs-dummy.o runtime.o compat.o
+extra-$(efi) += boot.init.o relocs-dummy.o runtime.o compat.o efi-shared.o
 
 stub.o: $(extra-y)
diff --git a/xen/arch/x86/efi/boot.c b/xen/arch/x86/efi/boot.c
index 2b515f2..2b6bea3 100644
--- a/xen/arch/x86/efi/boot.c
+++ b/xen/arch/x86/efi/boot.c
@@ -1,6 +1,7 @@
 #include "efi.h"
 #include <efi/efiprot.h>
 #include <efi/efipciio.h>
+#include <efi/efi-shared.h>
 #include <public/xen.h>
 #include <xen/compile.h>
 #include <xen/ctype.h>
@@ -44,25 +45,16 @@ typedef struct {
 extern char start[];
 extern u32 cpuid_ext_features;
 
-union string {
-    CHAR16 *w;
-    char *s;
-    const char *cs;
-};
 
-struct file {
-    UINTN size;
-    union {
-        EFI_PHYSICAL_ADDRESS addr;
-        void *ptr;
-    };
-};
+/* Variables supplied/used by shared EFI code. */
+extern CHAR16 __initdata newline[];
+extern EFI_BOOT_SERVICES *__initdata efi_bs;
+extern SIMPLE_TEXT_OUTPUT_INTERFACE *__initdata StdOut;
+extern SIMPLE_TEXT_OUTPUT_INTERFACE *__initdata StdErr;
+
 
-static EFI_BOOT_SERVICES *__initdata efi_bs;
 static EFI_HANDLE __initdata efi_ih;
 
-static SIMPLE_TEXT_OUTPUT_INTERFACE *__initdata StdOut;
-static SIMPLE_TEXT_OUTPUT_INTERFACE *__initdata StdErr;
 
 static UINT32 __initdata mdesc_ver;
 
@@ -77,111 +69,6 @@ static multiboot_info_t __initdata mbi = {
 };
 static module_t __initdata mb_modules[3];
 
-static CHAR16 __initdata newline[] = L"\r\n";
-
-#define PrintStr(s) StdOut->OutputString(StdOut, s)
-#define PrintErr(s) StdErr->OutputString(StdErr, s)
-
-static CHAR16 *__init FormatDec(UINT64 Val, CHAR16 *Buffer)
-{
-    if ( Val >= 10 )
-        Buffer = FormatDec(Val / 10, Buffer);
-    *Buffer = (CHAR16)(L'0' + Val % 10);
-    return Buffer + 1;
-}
-
-static CHAR16 *__init FormatHex(UINT64 Val, UINTN Width, CHAR16 *Buffer)
-{
-    if ( Width > 1 || Val >= 0x10 )
-        Buffer = FormatHex(Val >> 4, Width ? Width - 1 : 0, Buffer);
-    *Buffer = (CHAR16)((Val &= 0xf) < 10 ? L'0' + Val : L'a' + Val - 10);
-    return Buffer + 1;
-}
-
-static void __init DisplayUint(UINT64 Val, INTN Width)
-{
-    CHAR16 PrintString[32], *end;
-
-    if (Width < 0)
-        end = FormatDec(Val, PrintString);
-    else
-    {
-        PrintStr(L"0x");
-        end = FormatHex(Val, Width, PrintString);
-    }
-    *end = 0;
-    PrintStr(PrintString);
-}
-
-static CHAR16 *__init wstrcpy(CHAR16 *d, const CHAR16 *s)
-{
-    CHAR16 *r = d;
-
-    while ( (*d++ = *s++) != 0 )
-        ;
-    return r;
-}
-
-static int __init wstrcmp(const CHAR16 *s1, const CHAR16 *s2)
-{
-    while ( *s1 && *s1 == *s2 )
-    {
-        ++s1;
-        ++s2;
-    }
-    return *s1 - *s2;
-}
-
-static int __init wstrncmp(const CHAR16 *s1, const CHAR16 *s2, UINTN n)
-{
-    while ( n && *s1 && *s1 == *s2 )
-    {
-        --n;
-        ++s1;
-        ++s2;
-    }
-    return n ? *s1 - *s2 : 0;
-}
-
-static CHAR16 *__init s2w(union string *str)
-{
-    const char *s = str->s;
-    CHAR16 *w;
-    void *ptr;
-
-    if ( efi_bs->AllocatePool(EfiLoaderData, (strlen(s) + 1) * sizeof(*w),
-                              &ptr) != EFI_SUCCESS )
-        return NULL;
-
-    w = str->w = ptr;
-    do {
-        *w = *s++;
-    } while ( *w++ );
-
-    return str->w;
-}
-
-static char *__init w2s(const union string *str)
-{
-    const CHAR16 *w = str->w;
-    char *s = str->s;
-
-    do {
-        if ( *w > 0x007f )
-            return NULL;
-        *s = *w++;
-    } while ( *s++ );
-
-    return str->s;
-}
-
-static bool_t __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2)
-{
-    return guid1->Data1 == guid2->Data1 &&
-           guid1->Data2 == guid2->Data2 &&
-           guid1->Data3 == guid2->Data3 &&
-           !memcmp(guid1->Data4, guid2->Data4, sizeof(guid1->Data4));
-}
 
 static void __init noreturn blexit(const CHAR16 *str)
 {
diff --git a/xen/arch/x86/efi/efi-shared.c b/xen/arch/x86/efi/efi-shared.c
new file mode 100644
index 0000000..b9c563a
--- /dev/null
+++ b/xen/arch/x86/efi/efi-shared.c
@@ -0,0 +1,122 @@
+/* EFI code shared between architectures. */
+
+#include "efi.h"
+#include <efi/efiprot.h>
+#include <efi/efipciio.h>
+#include <efi/efi-shared.h>
+#include <public/xen.h>
+#include <efi/efi-shared.h>
+#include <xen/compile.h>
+#include <xen/ctype.h>
+#include <xen/init.h>
+#include <asm/processor.h>
+
+
+SIMPLE_TEXT_OUTPUT_INTERFACE *__initdata StdOut;
+SIMPLE_TEXT_OUTPUT_INTERFACE *__initdata StdErr;
+EFI_BOOT_SERVICES *__initdata efi_bs;
+
+
+CHAR16 __initdata newline[] = L"\r\n";
+
+CHAR16 *__init FormatDec(UINT64 Val, CHAR16 *Buffer)
+{
+    if ( Val >= 10 )
+        Buffer = FormatDec(Val / 10, Buffer);
+    *Buffer = (CHAR16)(L'0' + Val % 10);
+    return Buffer + 1;
+}
+
+CHAR16 *__init FormatHex(UINT64 Val, UINTN Width, CHAR16 *Buffer)
+{
+    if ( Width > 1 || Val >= 0x10 )
+        Buffer = FormatHex(Val >> 4, Width ? Width - 1 : 0, Buffer);
+    *Buffer = (CHAR16)((Val &= 0xf) < 10 ? L'0' + Val : L'a' + Val - 10);
+    return Buffer + 1;
+}
+
+
+void __init DisplayUint(UINT64 Val, INTN Width)
+{
+    CHAR16 PrintString[32], *end;
+
+    if (Width < 0)
+        end = FormatDec(Val, PrintString);
+    else
+    {
+        PrintStr(L"0x");
+        end = FormatHex(Val, Width, PrintString);
+    }
+    *end = 0;
+    PrintStr(PrintString);
+}
+
+CHAR16 *__init wstrcpy(CHAR16 *d, const CHAR16 *s)
+{
+    CHAR16 *r = d;
+
+    while ( (*d++ = *s++) != 0 )
+        ;
+    return r;
+}
+
+int __init wstrcmp(const CHAR16 *s1, const CHAR16 *s2)
+{
+    while ( *s1 && *s1 == *s2 )
+    {
+        ++s1;
+        ++s2;
+    }
+    return *s1 - *s2;
+}
+
+int __init wstrncmp(const CHAR16 *s1, const CHAR16 *s2, UINTN n)
+{
+    while ( n && *s1 && *s1 == *s2 )
+    {
+        --n;
+        ++s1;
+        ++s2;
+    }
+    return n ? *s1 - *s2 : 0;
+}
+
+CHAR16 *__init s2w(union string *str)
+{
+    const char *s = str->s;
+    CHAR16 *w;
+    void *ptr;
+
+    if ( efi_bs->AllocatePool(EfiLoaderData, (strlen(s) + 1) * sizeof(*w),
+                              &ptr) != EFI_SUCCESS )
+        return NULL;
+
+    w = str->w = ptr;
+    do {
+        *w = *s++;
+    } while ( *w++ );
+
+    return str->w;
+}
+
+char *__init w2s(const union string *str)
+{
+    const CHAR16 *w = str->w;
+    char *s = str->s;
+
+    do {
+        if ( *w > 0x007f )
+            return NULL;
+        *s = *w++;
+    } while ( *s++ );
+
+    return str->s;
+}
+
+bool_t __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2)
+{
+    return guid1->Data1 == guid2->Data1 &&
+           guid1->Data2 == guid2->Data2 &&
+           guid1->Data3 == guid2->Data3 &&
+           !memcmp(guid1->Data4, guid2->Data4, sizeof(guid1->Data4));
+}
diff --git a/xen/include/efi/efi-shared.h b/xen/include/efi/efi-shared.h
new file mode 100644
index 0000000..b4c7ac5
--- /dev/null
+++ b/xen/include/efi/efi-shared.h
@@ -0,0 +1,39 @@
+#ifndef __EFI_SHARED_H__
+#define __EFI_SHARED_H__
+
+#include <efi/efidef.h>
+#include <xen/init.h>
+
+
+union string {
+    CHAR16 *w;
+    char *s;
+    const char *cs;
+};
+
+struct file {
+    UINTN size;
+    union {
+        EFI_PHYSICAL_ADDRESS addr;
+        void *ptr;
+    };
+};
+
+
+#define PrintStr(s) StdOut->OutputString(StdOut, s)
+#define PrintErr(s) StdErr->OutputString(StdErr, s)
+
+
+
+CHAR16 * FormatDec(UINT64 Val, CHAR16 *Buffer);
+CHAR16 * FormatHex(UINT64 Val, UINTN Width, CHAR16 *Buffer);
+
+void __init DisplayUint(UINT64 Val, INTN Width);
+CHAR16 *__init wstrcpy(CHAR16 *d, const CHAR16 *s);
+int __init wstrcmp(const CHAR16 *s1, const CHAR16 *s2);
+int __init wstrncmp(const CHAR16 *s1, const CHAR16 *s2, UINTN n);
+CHAR16 *__init s2w(union string *str);
+char *__init w2s(const union string *str);
+bool_t __init match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2);
+
+#endif
