Run the emulation with:
  
   qemu-system-mips64el -M malta -kernel output/images/vmlinux -serial stdio -drive file=output/images/rootfs.ext2,format=raw -append "root=/dev/hda"
  
  The login prompt will appear in the terminal that started Qemu. The
  graphical window is the framebuffer.
  
  Tested with QEMU 2.5.0