diff --git a/configs/sama5d3-xplained/README.txt b/configs/sama5d3-xplained/README.txt
index 966ffa2a1cc..4e05e5feb09 100644
--- a/configs/sama5d3-xplained/README.txt
+++ b/configs/sama5d3-xplained/README.txt
@@ -501,7 +501,9 @@ Load NuttX with U-Boot on AT91 boards
     image with header information, CRC32 checksum, etc.
 
     mkimage comes in source code with U-Boot distribution and it is built
-    during U-Boot compilation (u-boot-source-dir/tools/mkimage).
+    during U-Boot compilation (u-boot-source-dir/tools/mkimage).  There
+    are also sites where you can download pre-built mkimage binaries.  For
+    example: http://www.trimslice.com/wiki/index.php/U-Boot_images
 
     See the U-Boot README file for more information.  More information is
     also available in the mkimage man page (for example,
@@ -524,6 +526,8 @@ Load NuttX with U-Boot on AT91 boards
       -n nuttx: Set image name.
       -d nuttx.bin: Use image data from nuttx.bin.
 
+    This will generate a binary called uImage.
+
   Loading through network
 
     On a development system, it is useful to get the kernel and root file
diff --git a/configs/sama5d3x-ek/README.txt b/configs/sama5d3x-ek/README.txt
index 18158b2b645..e1ac624faa3 100644
--- a/configs/sama5d3x-ek/README.txt
+++ b/configs/sama5d3x-ek/README.txt
@@ -622,7 +622,9 @@ Load NuttX with U-Boot on AT91 boards
     image with header information, CRC32 checksum, etc.
 
     mkimage comes in source code with U-Boot distribution and it is built
-    during U-Boot compilation (u-boot-source-dir/tools/mkimage).
+    during U-Boot compilation (u-boot-source-dir/tools/mkimage).  There
+    are also sites where you can download pre-built mkimage binaries.  For
+    example: http://www.trimslice.com/wiki/index.php/U-Boot_images
 
     See the U-Boot README file for more information.  More information is
     also available in the mkimage man page (for example,
@@ -645,6 +647,8 @@ Load NuttX with U-Boot on AT91 boards
       -n nuttx: Set image name.
       -d nuttx.bin: Use image data from nuttx.bin.
 
+    This will generate a binary called uImage.
+
   Loading through network
 
     On a development system, it is useful to get the kernel and root file