Android screen resolution change. how to do?

Hello!

I wanna change my screen resolution but i don't know how to do..

I searched and found one solution. but it said "change your kernel source".. is it right? if it does, plz let me know how to change and build. if not, plz let me know how to change.

my os: android jb 4.2.2 provider: TI
my display: 7inch touch hdmi lcd 800x480
my board: bbb
my host: x32 ubuntu, win7

I NEED YOUR HELP
Thank you