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Re: 32 Meg sdram



Mark Schapira wrote:
> are doing this by replacing the 16 Meg ram chip on our board with a 32
> Meg ram chip. We have recompiled the kernel to accomodate the 32 Megs

It's not that simple, at least 16 bit 32 MiB chips have one more address
line than 16 MiB chips, so you have to take care of that. And you have to
change the sdram_config register accordingly, see chapter 19 of Etrax100LX
designers reference.
Just draw the address bits for 32 MiB on paper, divide them to
column/row/bank select lines (see sdram datasheet) and calculate bit shift
values for the config register.
I think I once saw a howto-like document about this on the Axis website.


Good luck with the calculations.

Jarkko