[U-Boot-Users] errata CPU10 for MPC855 ?

Steven Scholz steven.scholz at imc-berlin.de
Wed Feb 5 17:17:10 CET 2003

Hi there,

I just stumbled over an old errata:

CPU10. Possible Excess Current Consumption in Deep Sleep Mode.

Certain nodes of the multiplier hardware are not initialized at reset, and may 
thus result in non-destructive internal contention. As a result, if the 
processor is put into Deep Sleep mode without first putting the multiplier
into a known state, current consumption in this mode may be higher than expected.

Execute a mullw instruction at any point after reset; this will put the internal 
nodes in an orderly state. Deep Sleep mode may then be entered at any time 

The only mullw's I found in post/cpu/asm.S.

I am not sure, but I guess these functions will only get called if I enable POST!?

So should we put "a mullw instruction at any point after reset"???



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