[PATCH] PPC440EPx SDRAM width

Josh Boyer jwboyer at linux.vnet.ibm.com
Thu Apr 23 23:45:38 EST 2009


On Thu, Apr 23, 2009 at 09:36:12AM -0400, Steven A. Falco wrote:
>There is an error in the way ibm4xx_denali_fixup_memsize calculates
>memory size.  When testing the DDR_REDUC bit, the polarity is
>backwards.  A "1" implies 32-bit wide memory while a "0" implies
>64-bit wide memory.
>
>For a 32-bit wide system, this bug causes twice the memory to be
>reported, leading to boot failure.
>
>Signed-off-by: Steven A. Falco <sfalco at harris.com>

So we had a previous patch for this, and a very long discussion on what the
right solution was.  Either we never came to a resolution, or I have just
forgotten what it was.

Stefan, Valentine, do either of you remember?  IIRC, it wasn't something that
effected Sequoia or Rainier, but it could (and obviously does) effect custom
boards.  I don't remember what we agreed on for the proper fix.

josh



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