diff --git a/gcc/config/aarch64/aarch64-opts.h b/gcc/config/aarch64/aarch64-opts.h
index 98d4519..b5bdf37 100644
--- a/gcc/config/aarch64/aarch64-opts.h
+++ b/gcc/config/aarch64/aarch64-opts.h
@@ -35,4 +35,10 @@ enum aarch64_processor
   aarch64_none
 };
 
+/* TLS types.  */
+enum aarch64_tls_type {
+  TLS_TRADITIONAL,
+  TLS_DESCRIPTORS
+};
+
 #endif
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 34d0475..129684b 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -188,9 +188,6 @@ static const struct aarch64_option_extension all_extensions[] =
    increment address.  */
 static enum machine_mode aarch64_memory_reference_mode;
 
-/* TLS dialects.  */
-enum tls_dialect aarch64_tls_dialect = TLS_DIALECT_DESC;
-
 /* Used to force GTY into this file.  */
 static GTY(()) int gty_dummy;
 
@@ -390,7 +387,7 @@ tls_symbolic_operand_type (rtx addr)
    add  dest, tmp, #:tlsgd_lo12:imm
    bl   __tls_get_addr
 
-   Global Dynamic - TLS Desc:
+   Global Dynamic - TLS Descriptors:
    adrp dest, :tlsdesc:imm
    ldr  tmp, [dest, #:tlsdesc_lo12:imm]
    add  dest, dest, #:tlsdesc_lo12:imm
@@ -4625,16 +4622,6 @@ aarch64_override_options (void)
 
   aarch64_build_bitmask_table ();
 
-  if (aarch64_tls_dialect_string)
-    {
-      if (strcmp (aarch64_tls_dialect_string, "traditional") == 0)
-        aarch64_tls_dialect = TLS_DIALECT_TRADITIONAL;
-      else if (strcmp (aarch64_tls_dialect_string, "desc") == 0)
-        aarch64_tls_dialect = TLS_DIALECT_DESC;
-      else
-        error ("bad value (%s) for -mtls-dialect", aarch64_tls_dialect_string);
-    }
-
   /* This target defaults to strict volatile bitfields.  */
   if (flag_strict_volatile_bitfields < 0 && abi_version_at_least (2))
     flag_strict_volatile_bitfields = 1;
diff --git a/gcc/config/aarch64/aarch64.h b/gcc/config/aarch64/aarch64.h
index 4a39d0b..7ad18d1 100644
--- a/gcc/config/aarch64/aarch64.h
+++ b/gcc/config/aarch64/aarch64.h
@@ -792,14 +792,8 @@ enum aarch64_builtins
 #define HARD_REGNO_CALL_PART_CLOBBERED(REGNO, MODE) \
 		(FP_REGNUM_P (REGNO) && GET_MODE_SIZE (MODE) > 8)
 
-#define TARGET_TLS_TRADITIONAL	(aarch64_tls_dialect == TLS_DIALECT_TRADITIONAL)
-#define TARGET_TLS_DESC		(aarch64_tls_dialect == TLS_DIALECT_DESC)
-
-enum tls_dialect
-{
-  TLS_DIALECT_TRADITIONAL,
-  TLS_DIALECT_DESC
-};
+/* Check TLS Descriptors mechanism is selected.  */
+#define TARGET_TLS_DESC (aarch64_tls_dialect == TLS_DESCRIPTORS)
 
 /* Used for the code generation strategy dependent on the
    memory model being used.
@@ -831,8 +825,6 @@ enum aarch64_memory_model
   AARCH64_MEM_MODEL_LARGE_PIC
 };
 
-extern enum tls_dialect aarch64_tls_dialect;
-
 extern enum aarch64_memory_model aarch64_default_mem_model;
 
 /* When using the tiny addressing model conditional and unconditional branches
diff --git a/gcc/config/aarch64/aarch64.opt b/gcc/config/aarch64/aarch64.opt
index 3cdd335..64e9ba8 100644
--- a/gcc/config/aarch64/aarch64.opt
+++ b/gcc/config/aarch64/aarch64.opt
@@ -21,6 +21,18 @@
 HeaderInclude
 config/aarch64/aarch64-opts.h
 
+; The TLS dialect names to use with -mtls-dialect.
+
+Enum
+Name(tls_type) Type(enum aarch64_tls_type)
+The possible TLS dialects:
+
+EnumValue
+Enum(tls_type) String(trad) Value(TLS_TRADITIONAL)
+
+EnumValue
+Enum(tls_type) String(desc) Value(TLS_DESCRIPTORS)
+
 ; The cpu/arch option names to use in cpu/arch selection.
 
 Variable
@@ -57,8 +69,8 @@ Target Report Save Var(flag_omit_leaf_frame_pointer) Init(1)
 Omit the frame pointer in leaf functions
 
 mtls-dialect=
-Target RejectNegative Joined Var(aarch64_tls_dialect_string)
-Use given thread-local storage dialect
+Target RejectNegative Joined Enum(tls_type) Var(aarch64_tls_dialect) Init(TLS_DESCRIPTORS)
+Specify TLS dialect
 
 march=
 Target RejectNegative Joined Var(aarch64_arch_string)