How to calculate the Code Length of PN sequence Block?

I have used the PN sequence block in my simulink model, which is a communication link consists of a transmitter, channel and reciever. And the PN sequence is used to spread the signal.

i need to vary the length of the code for my analyze but i don know how to measure the length of the code in PN sequence code using generator polynomials and its initial state.

 At the moment my generator polinomial is [1 1 0 0 0 1 1] and the initial state is [1 0 1 0 0 1]. If some one can help to measure the length of the code it would be greatfull.
Need help Please.