[U-Boot-Users] Ebony board with 32-bit DDR memory width

Brian Padalino bpadalino at perigee.com
Tue Aug 26 18:36:36 CEST 2003

I am trying to do a proof-of-concept here and I am just trying to make sure
that I am setting my registers properly, unfortunately I am not 100% certain
that the CPU is actually running in the mode I intend it to.

I have the original Ebony evaluation board, but , for testing purposes, I
need to run the 128meg stick of DDR memory it comes with in 32-bit mode.

These are the steps I have done in trying to do this.

1. ./u-boot/boards/ebony/ebony.c
  a. Line 182: 0x00084001 instead of 0x000a4001 (mem_b0cr)
  b. Line 193: 0x84800000 instead of 0x86000000 (mem_cfg0)
  c. Line 202: return ( 64 * 1024 * 1024 ) instead of ( 128 * 1024 * 1024 )

2. ./u-boot/include/config.h
  a. Make sure to undefine CONFIG_SPD_EEPROM so fixed_sdram() is used.

U-Boot says there is only 64-meg which I believe should be right, but I
don't know if that is simply because I am forcing it to say 64-meg or what.
I tried to replace it and say there was still 128-meg and that led to a
horrible fault.

When I boot into my Linux kernel, it also reports 64-meg of memory - but I
don't know if it is just getting that from u-boot or if it is going out and
finding it itself.

If anyone has any sugguestions or reassurances that this may be
proper/improper, correct/incorrect then it would be very helpful.

Brian Padalino

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