From mboxrd@z Thu Jan  1 00:00:00 1970
From: will.deacon@arm.com (Will Deacon)
Date: Tue, 9 Jul 2013 09:05:24 +0100
Subject: kernel decompressor problem for ARMv7
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To: linux-arm-kernel@lists.infradead.org
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On Tue, Jul 09, 2013 at 08:53:05AM +0100, Lin Ming wrote:
> On Tue, Jul 9, 2013 at 3:39 PM, Nicolas Pitre <nicolas.pitre@linaro.org> wrote:
> > No more info needed.  The kernel has to be booted with the MMU disabled
> > as per the booting protocol documentation. You therefore have to fix
> > your
> > bootloader.
> 
> OK.
> 
> But I have to also revert below commit to make decompressor work.
> 
> commit 5010192:
> ARM: 7583/1: decompressor: Enable unaligned memory access for v6 and above
> 
> It seems like caused by bootloader has Alignment fault checking enabled.
> Any suggestion how to fix it?

Well step 1 is to disable the MMU. Once you've done that, you really don't
want to be issuing unaligned accesses (since memory will be treated as
strongly-ordered), so the value of the alignment trap bit is irrelevant.

Will