[fedora-arm] Alignment Issues - TI OMAP and Marvell Kirkwood processors

[Matthew Wilson]

On 2 July 2010 15:03, Chris Tyler <chris at tylers.info> wrote:
> Oddly, the OMAP system always calculated the right value regardless of
> the fixups setting, while the Kirkwood needed fixups enabled to display
> the right value. Why do the two processors act differently? Does the
> OMAP processor have additional logic handle to handle non-aligned
> access? [snip]

Yes.  The OMAP3530's Cortex-A8 supports unaligned memory accesses.
There will be an overhead for accessing what is actually two memory
locations and fixing the result, but it'll be nothing like the
overhead of causing an abort and handling it in the kernel.

See, for example:

http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0344k/Beihgifg.html

Hope that helps,
Matthew