dtc: Don't force alignment of cell list data

Jon Loeliger jdl at jdl.com
Tue Nov 6 01:59:44 EST 2007

So, like, the other day David Gibson mumbled:
> At present, defining a property as, say:
> 	foo = [abcd], <ffffffff>;
> Will cause dtc to insert 2 bytes of zeros between the abcd and the
> ffffffff, to align the cell form data.
> Doing so seemed like a good idea at the time, but I don't believe
> there are any users who actually rely on this behaviour.  Segher
> claims that OF has some defined bindings which include properties an
> unaligned subsection of which is interpreted as 32-bit ints (i.e. like
> cell data).
> Worse, this alignment will cause nothing but pain when we add
> expression support to dtc (when celldata is included in a larger
> bytestring expession, we won't know the size of the preceding chunk of
> the expression until it's evaluated, so we would have to carry
> alignment fixup information right through the expression evaluation
> process).
> Therefore, this patch kills off this alignment behaviour.
> Signed-off-by: David Gibson <david at gibson.dropbear.id.au>



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