Fast (memory mapped) GPIO pin access

Lubo

I need to implement fast GPIOs in my c-code application, so I try to use
mraa_gpio_use_mmaped()
However it return %UNSUPPORTED_FEATURE% error ..., so I am not able to use mraa for this probebly. Is tehre any other way to have quick acess to GPIO ?
I have UPBoard with Ubilinux installed.