Here's a couple cheats that i found for you. Hopefully they are what you were looking for but if not then just let me now and i'll see if i can find some more for you. Enter the Goals/Notes/Images screen. Press L2, R2, L1, R1, Start, Start, Start to display another tab on this screen with the following options:
God
Full Health
Full Energy
Full Ammo
Full Mods
All Skills
Full Credits
Tantalus
Well, i hope that you enjoy posting and have fun gaming. :thumbsup: