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Date:   Mon, 21 Feb 2022 16:42:52 +0000 (GMT)
From:   "Maciej W. Rozycki" <macro@orcam.me.uk>
To:     Jiaxun Yang <jiaxun.yang@flygoat.com>
cc:     linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
        chenhuacai@kernel.org, tsbogend@alpha.franken.de
Subject: Re: [RFC PATCH 2/3] MIPS: io.h use barrier terminology from
 asm-generic
In-Reply-To: <20220221145531.10479-3-jiaxun.yang@flygoat.com>
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References: <20220221145531.10479-1-jiaxun.yang@flygoat.com> <20220221145531.10479-3-jiaxun.yang@flygoat.com>
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On Mon, 21 Feb 2022, Jiaxun Yang wrote:

> So we can share understanding of those barriers with other archs
> and hopefully one day we will be able to switch asm-generic.

 You're mixing the ordering of DMA WRT MMIO here with the ordering of MMIO 
WRT itself, and this single line of justification does not explain why it 
is a change worth making.  You're free to define additional DMA barriers 
if we're missing some.

  Maciej