diff --git a/include/configs/at91sam9n12ek.h b/include/configs/at91sam9n12ek.h
index be8a28c..28a7925 100644
--- a/include/configs/at91sam9n12ek.h
+++ b/include/configs/at91sam9n12ek.h
@@ -122,6 +122,9 @@
 #define CONFIG_PMECC_CAP		2
 #define CONFIG_PMECC_SECTOR_SIZE	512
 #define CONFIG_PMECC_INDEX_TABLE_OFFSET	0x8000
+
+#define CONFIG_CMD_NAND_TRIMFFS
+
 #endif
 
 #define CONFIG_MTD_PARTITIONS
diff --git a/include/configs/at91sam9x5ek.h b/include/configs/at91sam9x5ek.h
index 2b1533c..b866a4b 100644
--- a/include/configs/at91sam9x5ek.h
+++ b/include/configs/at91sam9x5ek.h
@@ -123,6 +123,8 @@
 #define CONFIG_PMECC_SECTOR_SIZE	512
 #define CONFIG_PMECC_INDEX_TABLE_OFFSET	0x8000
 
+#define CONFIG_CMD_NAND_TRIMFFS
+
 #define CONFIG_MTD_DEVICE
 #define CONFIG_CMD_MTDPARTS
 #define CONFIG_MTD_PARTITIONS