TLB and CSSBAR problems with MPC8540 and BDI2000

Matthew S. McClintock mattsm at
Sat Jan 10 09:18:18 EST 2004

>      Yes, but that isn't the problem.
> >         Could anyone familiar with that workaround listed below verify
> > that
> > this could be causing the CPU to freeze/crash?
>      I've been there and done it.  The CCSRBAR can't be changing while you
>      are using the BDI2000 for debug.  The debug registers the BDI2000 is
>      trying to access are in this space.  If you move the space without the
>      BDI2000 knowing (i.e. in your code), the BDI2000 doesn't seem to be
>      able to track those changes and continues to try and access the
>      debug registers in the last known space.
>      So, what you have to do is (simply :-) ensure the CCSRBAR isn't
>      changing when you are debugging the software.

That leaves me with one question. When I don't do anything in the init
section of the bdi2000 except one command which is to remove the L2SRAM
from the initial MMU page and then I proceed with booting the board
boots fine. If I halt the board examine the CCSRBAR it has moved from
the default location.

I must be missing something, any ideas?


Matthew S. McClintock <mattsm at>

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