mpc852t boot question!

 I made a MPC852T board. I set the HW config word to 0x04600000(D5,D9,D10
pulled up).So the [ISB]=00, 
 
and the IMMR = 0x00000000. 
 
 When the CPU is power up, can it boot from external boot flash(39vf040)? Or
just run from internal 
 
memory space(because the IMMR=0x0)?