DTS question - MPC5200b

[Nick]

Hi,

I need some help.  I am trying to access timer 7 on the MPC5200B 
processor.  I have the DTS file setup like this

        gpt at 670 {    // General Purpose Timer
          device_type = "gpt";
            compatible = "fsl,mpc5200b-gpt","fsl,mpc5200-gpt";
            cell-index = <7>;
            reg = <670 10>;
            interrupts = <1 10 0>;
            interrupt-parent = <&mpc5200_pic>;
        };

I have timers 0 to 6 defined the same way except the cell-index reflects 
the timer number.

In my platform file where I am doing my board setup, I tried the  following.

timer7 = mpc52xx_find_and_map ("mpc5200b-gpt");

How do I specify the timer based on the cell-index?

Thanks

Nick