SDRAM failures on MPC5200B

[lokowich]

We're working on bringing up a MPC5200B version of our original MPC5200 
board using U-Boot 1.1.4 configured for Icecube/Lite5200B.  Other than 
the CPU, the board is identical.  The bootloader crashes just after 
relocation to RAM, often with a Program Check Exception, typically a 
memory corruption issue.  I noticed failures at different stages after 
relocation based on content, suggesting problems with upper SDRAM.  If I 
force the initram to 1/2 the determined size (64MB instead of 128MB), 
then everything works well through kernel load and initialization.  
We've added termination resistors to improve AD signals, to no avail.  
Memory tests work fine too.  Any help is appreciated.

Thanks,
Mark Lokowich
Systems Engineer
Advanced Communication Design
7901 12th Ave. So.
Bloomington, MN 55425
952-854-4000
lokowich at acdstar.com

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