Thanks Biser for the hint.
First: I should update my resources.
Second: Regarding the PRUSS i will investigate the possibilities, thanks.
Additional:
For Bitbanging, the PRUSS sounds good. But for high input/output data Rates, the Input datatransfer is limited because of the needed PRUSS-Code. (http://e2e.ti.com/support/arm/sitara_arm/f/791/t/149413.aspx)
For high data throughput, the gpmc interface sounds good. (http://e2e.ti.com/support/arm/sitara_arm/f/791/t/312694.aspx)
Greetings
Martin