diff --git a/configs/iocon_defconfig b/configs/iocon_defconfig
index 211a734..c74df94 100644
--- a/configs/iocon_defconfig
+++ b/configs/iocon_defconfig
@@ -21,6 +21,7 @@
 CONFIG_CMD_MII=y
 CONFIG_CMD_PING=y
 CONFIG_CMD_CACHE=y
+CONFIG_CMD_DIAG=y
 # CONFIG_MMC is not set
 CONFIG_MTD_NOR_FLASH=y
 # CONFIG_PCI is not set