diff --git a/README b/README
index 0a60097..c16bb5d 100644
--- a/README
+++ b/README
@@ -22,11 +22,11 @@ Required Options:
                 am335x-bone-serial
                 am335x-bone-video
                 am335x-boneblack
-                omap3-beagle
+                omap3-beagle (serial only)
                 omap3-beagle-xm
-                omap4-panda
-                omap4-panda-a4
-                omap4-panda-es
+                omap4-panda (serial only)
+                omap4-panda-a4 (serial only)
+                omap4-panda-es (serial only)
 
 Optional:
 --distro <distro>
diff --git a/mk_mmc.sh b/mk_mmc.sh
index ced61e9..66199e6 100755
--- a/mk_mmc.sh
+++ b/mk_mmc.sh
@@ -1623,11 +1623,11 @@ usage () {
 			                am335x-bone-serial
 			                am335x-bone-video
 			                am335x-boneblack
-			                omap3-beagle
+			                omap3-beagle (serial only)
 			                omap3-beagle-xm
-			                omap4-panda
-			                omap4-panda-a4
-			                omap4-panda-es
+			                omap4-panda (serial only)
+			                omap4-panda-a4 (serial only)
+			                omap4-panda-es (serial only)
 
 			Optional:
 			--distro <distro>