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Subject: Re: RFC on writel and writel_relaxed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Will Deacon <will.deacon@arm.com>
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Date: Tue, 27 Mar 2018 22:21:27 +1100
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On Tue, 2018-03-27 at 10:57 +0100, Will Deacon wrote:
> > 
> > The interesting thing is that we do seem to have a whole LOT of these
> > spurrious wmb before writel all over the tree, I suspect because of
> > that incorrect recommendation in memory-barriers.txt.
> > 
> > We should fix that.
> 
> Patch below. Thoughts?

Looks good, we should probably also have a clearer (explicit)
definition of that ordering in the driver-api doco.

Now, to remove all those useless wmb's and find what other bugs they
were papering over ... ;-)

Cheers,
Ben.