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Date: Wed, 08 Aug 2007 11:49:29 -0500
From: Scott Wood <scottwood@freescale.com>
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To: Yoni Levin <yoni.l@slyde-tech.com>
Subject: Re: how the bytes ordered in mpc8313
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Yoni Levin wrote:
> I have mpc83xx,
> 
> I saw that I need to use swab32 to any read\write operation from registers,

Only little endian registers (such as PCI).

> Why in the mpc8313 reference in registers description some bits look like
> 31,30,29,.,3,2,1,0
> 
> And some: 0,1,2,3.,30,31

Most PowerPC documentation numbers bits in the same endianness as the 
bytes in the register.

> Is it just mistake? Or some registers are different then other? 

I consider big-endian bit numbering to be a mistake, but good luck 
getting them to fix it. :-)

-Scott