diff --git a/mkroot/mkroot.sh b/mkroot/mkroot.sh
index 1a2326345..d2cbd44f1 100755
--- a/mkroot/mkroot.sh
+++ b/mkroot/mkroot.sh
@@ -254,9 +254,8 @@ get_target_config()
       KCONF+=,64BIT,CPU_MIPS64_R1,MIPS32_O32
     [ "${CROSS%el}" != "$CROSS" ] && KCONF+=,CPU_LITTLE_ENDIAN
   elif [ "$CROSS" == or1k ]; then
-    KARCH=openrisc QEMU_M=or1k-sim KARGS=FIXME BUILTIN=1
+    KARCH=openrisc QEMU_M=or1k-sim KARGS=ttyS0
     KCONF="$(be2csv ETHOC SERIO SERIAL_OF_PLATFORM SERIAL_8250{,_CONSOLE})"
-    KCONF+=,OPENRISC_BUILTIN_DTB=\"or1ksim\"
   elif [ "$CROSS" == powerpc ]; then
     KARCH=powerpc QEMU="ppc -M g3beige"
     KCONF="$(be2csv ALTIVEC PATA_MACIO BLK_DEV_SD MACINTOSH_DRIVERS SERIO \