diff --git a/xen/arch/x86/dmi_scan.c b/xen/arch/x86/dmi_scan.c
index 8e07f8d..4cd38c8 100644
--- a/xen/arch/x86/dmi_scan.c
+++ b/xen/arch/x86/dmi_scan.c
@@ -238,7 +238,7 @@ const char *__init dmi_get_table(paddr_t *base, u32 *len)
 {
 	static unsigned int __initdata instance;
 
-	if (efi_enabled) {
+	if (efi_enabled(EFI_PLATFORM)) {
 		if (efi_smbios3_size && !(instance & 1)) {
 			*base = efi_smbios3_address;
 			*len = efi_smbios3_size;
@@ -702,7 +702,7 @@ static void __init dmi_decode(struct dmi_header *dm)
 
 void __init dmi_scan_machine(void)
 {
-	if ((!efi_enabled ? dmi_iterate(dmi_decode) :
+	if ((!efi_enabled(EFI_PLATFORM) ? dmi_iterate(dmi_decode) :
 	                    dmi_efi_iterate(dmi_decode)) == 0)
  		dmi_check_system(dmi_blacklist);
 	else
diff --git a/xen/arch/x86/domain_page.c b/xen/arch/x86/domain_page.c
index d86f8fe..fdf0d8a 100644
--- a/xen/arch/x86/domain_page.c
+++ b/xen/arch/x86/domain_page.c
@@ -36,7 +36,7 @@ static inline struct vcpu *mapcache_current_vcpu(void)
      * domain's page tables but current may point at another domain's VCPU.
      * Return NULL as though current is not properly set up yet.
      */
-    if ( efi_enabled && efi_rs_using_pgtables() )
+    if ( efi_enabled(EFI_PLATFORM) && efi_rs_using_pgtables() )
         return NULL;
 
     /*
diff --git a/xen/arch/x86/efi/stub.c b/xen/arch/x86/efi/stub.c
index e6c99b5..c5ae369 100644
--- a/xen/arch/x86/efi/stub.c
+++ b/xen/arch/x86/efi/stub.c
@@ -4,11 +4,8 @@
 #include <xen/lib.h>
 #include <asm/page.h>
 
-#ifndef efi_enabled
-const bool_t efi_enabled = 0;
-#endif
-
 struct efi __read_mostly efi = {
+	.flags   = 0, /* Initialized later. */
 	.acpi    = EFI_INVALID_TABLE_ADDR,
 	.acpi20  = EFI_INVALID_TABLE_ADDR,
 	.mps     = EFI_INVALID_TABLE_ADDR,
diff --git a/xen/arch/x86/mpparse.c b/xen/arch/x86/mpparse.c
index ef6557c..ff26b5a 100644
--- a/xen/arch/x86/mpparse.c
+++ b/xen/arch/x86/mpparse.c
@@ -564,7 +564,7 @@ static inline void __init construct_default_ISA_mptable(int mpc_default_type)
 
 static __init void efi_unmap_mpf(void)
 {
-	if (efi_enabled)
+	if (efi_enabled(EFI_PLATFORM))
 		clear_fixmap(FIX_EFI_MPF);
 }
 
@@ -722,7 +722,7 @@ void __init find_smp_config (void)
 {
 	unsigned int address;
 
-	if (efi_enabled) {
+	if (efi_enabled(EFI_PLATFORM)) {
 		efi_check_config();
 		return;
 	}
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index c5c332d..5d80868 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -434,8 +434,8 @@ static void __init parse_video_info(void)
 {
     struct boot_video_info *bvi = &bootsym(boot_vid_info);
 
-    /* The EFI loader fills vga_console_info directly. */
-    if ( efi_enabled )
+    /* vga_console_info is filled directly on EFI platform. */
+    if ( efi_enabled(EFI_PLATFORM) )
         return;
 
     if ( (bvi->orig_video_isVGA == 1) && (bvi->orig_video_mode == 3) )
@@ -715,7 +715,7 @@ void __init noreturn __start_xen(unsigned long mbi_p)
     if ( !(mbi->flags & MBI_MODULES) || (mbi->mods_count == 0) )
         panic("dom0 kernel not specified. Check bootloader configuration.");
 
-    if ( efi_enabled )
+    if ( efi_enabled(EFI_PLATFORM) )
     {
         set_pdx_range(xen_phys_start >> PAGE_SHIFT,
                       (xen_phys_start + BOOTSTRAP_MAP_BASE) >> PAGE_SHIFT);
@@ -826,7 +826,7 @@ void __init noreturn __start_xen(unsigned long mbi_p)
      * we can relocate the dom0 kernel and other multiboot modules. Also, on
      * x86/64, we relocate Xen to higher memory.
      */
-    for ( i = 0; !efi_enabled && i < mbi->mods_count; i++ )
+    for ( i = 0; !efi_enabled(EFI_PLATFORM) && i < mbi->mods_count; i++ )
     {
         if ( mod[i].mod_start & (PAGE_SIZE - 1) )
             panic("Bootloader didn't honor module alignment request.");
@@ -1057,7 +1057,7 @@ void __init noreturn __start_xen(unsigned long mbi_p)
 
     if ( !xen_phys_start )
         panic("Not enough memory to relocate Xen.");
-    reserve_e820_ram(&boot_e820, efi_enabled ? mbi->mem_upper : __pa(&_start),
+    reserve_e820_ram(&boot_e820, efi_enabled(EFI_PLATFORM) ? mbi->mem_upper : __pa(&_start),
                      __pa(&_end));
 
     /* Late kexec reservation (dynamic start address). */
diff --git a/xen/arch/x86/shutdown.c b/xen/arch/x86/shutdown.c
index 0e1499d..79dcd16 100644
--- a/xen/arch/x86/shutdown.c
+++ b/xen/arch/x86/shutdown.c
@@ -116,7 +116,7 @@ void machine_halt(void)
 static void default_reboot_type(void)
 {
     if ( reboot_type == BOOT_INVALID )
-        reboot_type = efi_enabled ? BOOT_EFI
+        reboot_type = efi_enabled(EFI_PLATFORM) ? BOOT_EFI
                                   : acpi_disabled ? BOOT_KBD
                                                   : BOOT_ACPI;
 }
diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index 687e39b..ffd39b2 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -686,7 +686,7 @@ static unsigned long get_cmos_time(void)
     static bool_t __read_mostly cmos_rtc_probe;
     boolean_param("cmos-rtc-probe", cmos_rtc_probe);
 
-    if ( efi_enabled )
+    if ( efi_enabled(EFI_PLATFORM) )
     {
         res = efi_get_time();
         if ( res )
diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index 125c9ce..f006575 100644
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -934,6 +934,10 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
     char *option_str;
     bool_t use_cfg_file;
 
+#ifndef CONFIG_ARM /* Disabled until runtime services implemented. */
+    set_bit(EFI_PLATFORM, &efi.flags);
+#endif
+
     efi_init(ImageHandle, SystemTable);
 
     use_cfg_file = efi_arch_use_config_file(SystemTable);
diff --git a/xen/common/efi/runtime.c b/xen/common/efi/runtime.c
index ae87557..aa064e7 100644
--- a/xen/common/efi/runtime.c
+++ b/xen/common/efi/runtime.c
@@ -10,14 +10,10 @@ DEFINE_XEN_GUEST_HANDLE(CHAR16);
 
 #ifndef COMPAT
 
-#ifdef CONFIG_ARM  /* Disabled until runtime services implemented */
-const bool_t efi_enabled = 0;
-#else
+#ifndef CONFIG_ARM
 # include <asm/i387.h>
 # include <asm/xstate.h>
 # include <public/platform.h>
-
-const bool_t efi_enabled = 1;
 #endif
 
 unsigned int __read_mostly efi_num_ct;
@@ -42,11 +38,12 @@ UINT64 __read_mostly efi_boot_remain_var_store_size;
 UINT64 __read_mostly efi_boot_max_var_size;
 
 struct efi __read_mostly efi = {
-	.acpi   = EFI_INVALID_TABLE_ADDR,
-	.acpi20 = EFI_INVALID_TABLE_ADDR,
-	.mps    = EFI_INVALID_TABLE_ADDR,
-	.smbios = EFI_INVALID_TABLE_ADDR,
-	.smbios3 = EFI_INVALID_TABLE_ADDR,
+	.flags   = 0, /* Initialized later. */
+	.acpi    = EFI_INVALID_TABLE_ADDR,
+	.acpi20  = EFI_INVALID_TABLE_ADDR,
+	.mps     = EFI_INVALID_TABLE_ADDR,
+	.smbios  = EFI_INVALID_TABLE_ADDR,
+	.smbios3 = EFI_INVALID_TABLE_ADDR
 };
 
 const struct efi_pci_rom *__read_mostly efi_pci_roms;
diff --git a/xen/drivers/acpi/osl.c b/xen/drivers/acpi/osl.c
index 8a28d87..eb8bc12 100644
--- a/xen/drivers/acpi/osl.c
+++ b/xen/drivers/acpi/osl.c
@@ -66,7 +66,7 @@ void __init acpi_os_vprintf(const char *fmt, va_list args)
 
 acpi_physical_address __init acpi_os_get_root_pointer(void)
 {
-	if (efi_enabled) {
+	if (efi_enabled(EFI_PLATFORM)) {
 		if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
 			return efi.acpi20;
 		else if (efi.acpi != EFI_INVALID_TABLE_ADDR)
diff --git a/xen/include/xen/efi.h b/xen/include/xen/efi.h
index e74dad1..659c7c4 100644
--- a/xen/include/xen/efi.h
+++ b/xen/include/xen/efi.h
@@ -2,15 +2,17 @@
 #define __XEN_EFI_H__
 
 #ifndef __ASSEMBLY__
+#include <xen/bitops.h>
 #include <xen/types.h>
 #endif
 
-extern const bool_t efi_enabled;
-
 #define EFI_INVALID_TABLE_ADDR (~0UL)
 
+#define EFI_PLATFORM	0
+
 /* Add fields here only if they need to be referenced from non-EFI code. */
 struct efi {
+    unsigned long flags;
     unsigned long mps;          /* MPS table */
     unsigned long acpi;         /* ACPI table (IA64 ext 0.71) */
     unsigned long acpi20;       /* ACPI table (ACPI 2.0) */
@@ -40,6 +42,12 @@ int efi_runtime_call(struct xenpf_efi_runtime_call *);
 int efi_compat_get_info(uint32_t idx, union compat_pf_efi_info *);
 int efi_compat_runtime_call(struct compat_pf_efi_runtime_call *);
 
+/* Test whether the above EFI_* bits are enabled. */
+static inline bool_t efi_enabled(int feature)
+{
+    return test_bit(feature, &efi.flags) != 0;
+}
+
 #endif /* !__ASSEMBLY__ */
 
 #endif /* __XEN_EFI_H__ */
