[U-Boot-Users] Questions about the U-Boot README, esp. CFG_IMMR

I got another question

About CFG_IMMR the README says: DO NOT CHANGE! (MPC8xx systems only)

This confuses me. As the IMMR is a SPR (special purpose register) in the MPC8xx, assigning it an address seems to make no sense.

Nevertheless CFG_IMMR is used everywhere in the U-Boot code, so there must be a preset for it, which I can't find in the source. Also, almost any config in include/configs sets this to 0xFF000000. So what is it good for and what should I choose?

Peter Asemann