how the bytes ordered in mpc8313

Scott Wood scottwood at
Thu Aug 9 02:49:29 EST 2007

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. :-)


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