1 files changed, 3 insertions, 0 deletions
diff --git a/README b/README
index ff4926040b..216f0c70aa 100644
--- a/README
+++ b/README
@@ -3470,6 +3470,9 @@ typically in board_init_f() and board_init_r().
 Configuration Settings:
 -----------------------
 
+- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
+		Optionally it can be defined to support 64-bit memory commands.
+
 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
 		undefine this when you're short of memory.