[fedora-arm] BeagleBone Black CPU speed

Hi, It looks like the BeagleBone Black is still running at 550MHz with the latest Fedora 20. Does anyone know what is holding it back from running at 1GHz? Is the a uboot thing, or a kernel thing, or something else? I saw a version of uboot referred to as making the BBB run at 1GHz, but when I tried experimenting with that I got the same 550MHz clock speed. Regards, Steve