diff --git a/arch/nios2/lib/bootm.c b/arch/nios2/lib/bootm.c
index 114e146..51597ea 100644
--- a/arch/nios2/lib/bootm.c
+++ b/arch/nios2/lib/bootm.c
@@ -45,6 +45,12 @@
 	if (of_flat_tree)
 		initrd_end = (ulong)of_flat_tree;
 
+	/*
+	 * allow the PREP bootm subcommand, it is required for bootm to work
+	 */
+	if (flag & BOOTM_STATE_OS_PREP)
+		return 0;
+
 	if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
 		return 1;