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From: Segher Boessenkool <segher@kernel.crashing.org>
Date: Thu, 14 Jul 2005 15:29:30 +0200
To: David Gibson <david@gibson.dropbear.id.au>
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Cc: "linuxppc-dev@ozlabs.org" <linuxppc-dev@ozlabs.org>
Subject: Re: PATCH: Add memreserve to DTC
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> My mistake, I misunderstood the terminology.  But the basic point is
> that lots of things in the kernel already assume a cell is 32-bits, so
> it would be silly to try and change that here.  This is not true for
> the memreserve values.

Of course you should use 32-bit values; but please just don't call it
a cell, there's nothing more confusing than messing up terminology.

>> Btw -- beware of the fact that such an "int" does _not_ have any
>> alignment restrictions -- so you better read it byte by byte...
>
> Erm.. in what context.  dtc never reads ints from the blob format as
> ints - properties are just byte strings to it.  At present you can't
> mix cell input format with other sorts, which means the ints must, in
> fact, be aligned, since properties are.

When reading integers from properties that have been created by an OF
implementation.  Whether this is a problem for DTC or not, I don't know;
I just thought I'd mention the problem to you, people fall in that trap
again and again.


Segher