[U-Boot-Users] Can MPC processors boot though the IMMR is at 0x0 (default configuration)?

[Dan Malek]

On May 22, 2005, at 10:06 AM, Peter Asemann wrote:

> I'm going to try booting u-boot on a custom MPC875 board.
> It has flash at the boot memory bank (bank 0).
> It has no circuit to pull up pin 7/8 of the MPC data bus at processor
> start, so (the manual says) the IMMR/the internal memory is configured
> to reside at 0x0.

The default configuration if you don't pull up any of the
configuration pins is IMMR at 0, rom boot vector at 0xfff00100,
and 32-bit flash (among other things you need to verify).
If this matches your hardware configuration, you can boot it,
and then the U-Boot relocates itself and IMMR to standard locations.

> The board designer says he can't believe the MPC875 default
> configuration is like that boards which use it can't boot.

I'd find a new designer because they obviously don't know
how this processor works.

Thanks.


	-- Dan