From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: RFC on writel and writel_relaxed
Date: Wed, 28 Mar 2018 20:50:16 +1100
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To: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>, Jonathan Corbet <corbet@lwn.net>, "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>, Sinan Kaya <okaya@codeaurora.org>, Jason Gunthorpe <jgg@ziepe.ca>, Peter Zijlstra <peterz@infradead.org>, David Laight <David.Laight@aculab.com>, Oliver <oohall@gmail.com>, "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, "open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)" <linuxppc-dev@lists.ozlabs.org>, Ingo Molnar <mingo@redhat.com>
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On Wed, 2018-03-28 at 09:53 +0100, Will Deacon wrote:
> For arm/arm64 these end up behaving exactly the same as readX/writeX, but
> I'm nervous about changing the documentation without understanding why it's
> like it is currently. Maybe another ia64 thing?.

I doubt it ... the Intel ancestry here would make me think they are
completely ordered there too.

powerpc and ARM can't quite make them synchronous I think, but at least
they should have the same semantics as writel.

Cheers,
Ben.