Endianness versus too many byte swaps??

["Charles Krinke" <ckrinke@istor.com>]

This is probably a Timur question, but any enlightment is appreciated. =
This concerns Linux-2.6.17.11 from kernel.org with some modifications =
for our custom 8541 board. The original BSP was evolved from =
mpc85xx_cds.
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Down in the guts of arch/ppc/syslib/ppc85xx_seteup.c is a routine called =
mpc85xx_setup_pci1(). In this routine we do an assignment of some =
outbound window registers and I am most interested in POTAR2, POWAR2 & =
POWBAR2 right now.
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This routine uses a ccsr_pci struct to assign potar2, powar2, powbar2 =
and others like this:
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pci->potar2     =3D 0x00100000;
pci->powar2   =3D 0x8004401a;
pci->powbar2 =3D 0x00888000;
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Where I have changed the constants for our board. The issue is that when =
I call readl to read back these same registers at the end of this same =
subroutine, I get into endianess issues. That is, I read back
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POTAR2     =3D=3D 0x00001000
POWAR2   =3D=3D 0x1A400480
POWBAR2 =3D=3D 0x00800800
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Where the four bytes in each 32bit word are now exchanged so that =
80_04_40_1A became 1A_40_04_80.
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I understand big versus little endian, that isn't the question. The =
question is "What is really in the POTAR2, POWAR2 & POWBAR2 registers =
and how can I prove that what is in the registers is really what I wish =
to be in the registers?"
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It may be that one or more endian swap things are going on within Linux =
and I have inherited some source from others, so actually proving what =
is in the registers is becoming important.
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Charles