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From: Sylvain Munaut <tnt@246tNt•com>
To: Mark Chambers <markc@mail•com>
Cc: linuxppc-embedded@ozlabs•org
Subject: Re: MPC5200 PCI byte-swapping
Date: Sat, 01 Jan 2005 23:39:26 +0100	[thread overview]
Message-ID: <41D7269E.1070906@246tNt.com> (raw)
In-Reply-To: <061001c4eeaf$0b5e1860$0301a8c0@chuck2>

Mark Chambers wrote:

>I've just realized that the 5200 does byte-lane swapping
>on all PCI accesses.  That is, if you write a 32 bit word
>0x12345678, 0x12 will go out on byte 0, 0x34 on byte 1,
>etc.  Unfortunately, my target, a T.I. DM642, does not
>do this, so I've got a big/little endian mismatch.  A couple
>of questions if anybody knows:
>
>- Do all MPC8xxx processors do this - byte swap on
>all PCI accesses, not just configuration space?
>
>- Is there an elegant (simple) way to re-swap the bytes?
>It's not a big problem really, but if there were a way to 
>set LE mode on a particular page or something like that
>it might be worth it.
>
>  
>
I'm not sure of what you mean but look at the mapping
aroung pdf page 337 of the user manual. It's not configurable
as far as I can see.


    Sylvain

  reply	other threads:[~2005-01-01 22:38 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-12-30 11:46 SMC/SCC uart problem with MPC852T David Jander
2004-12-30 15:30 ` Dan Malek
2004-12-30 20:35   ` MPC5200 PCI byte-swapping Mark Chambers
2005-01-01 22:39     ` Sylvain Munaut [this message]
2005-01-03 14:07       ` Mark Chambers
2005-01-03 16:47         ` Sylvain Munaut
2005-01-04  9:37           ` Stefan Nickl

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