[U-Boot-Users] data bus bit reversal

Wolfgang Denk wd at denx.de
Tue Apr 1 00:23:46 CEST 2003

In message <01C2F78D.563A35A0.robdlg at att.net> you wrote:
> I have a question that isn't strictly related to U-Boot.  I hope it's not 
> unacceptable.

This is perfectly ok. I could not think of a  better  place  to  ask,

> The old PPCBoot source included a macro used during Flash programming on a 
> Musenki board (I suppose the U-Boot code still contains this, but I haven't 

It should still be there. At least I'm not aware that it was thrown out.

> My question is this: are there other Flash programmers (such as the one in 
> the BDI2000) that can indeed compensate for the bit reversal?

The standard firmware for the BDI2000 does not provide this  feature.
But  I  know  that  Abatron provided such a solution as part of their
excellent support - within less than a day AFAIR.

I guess this solution is still available.

> My current plan is to use custom Flash programming code running in SDRAM, 
> but it would be nice if there was a tool that let me bypass this process.

We encountered similar problems before; this is one of the  very  few
cases  where I think that starting with a version of U-Boot that gets
loaded to RAM first actually makes sense.

> Again, I hope this message isn't too far off-topic.  Thanks for any help.

You are welcome.

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
The IQ of the group is the lowest IQ of a member of the group divided
by the number of people in the group.

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