I have been working on Angstrom2010.07 build all these years. I could change the value of 'scaling_governor' in this built. On changing from 'Userspace' to 'Performance' mode, the BogoMIPS value gets modified from around 500 to 720 in Beagleboard.
I later downloaded a new Angstrom built v2012.05. On doing the above method, no changes occur to BogoMIPS. The value remains 600, no matter whatever the value of scaling_governor be.
Is this a bug in the built, or is their any thing that I am missing