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Date:   Mon, 13 Jan 2020 15:58:20 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc:     linux-mips@vger.kernel.org, chenhc@lemote.com,
        paul.burton@mips.com, linux-kernel@vger.kernel.org, hch@lst.de
Subject: Re: [PATCH 1/2] MIPS: Define pgprot_dmacoherent according to
 coherentio status
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References: <20200113140705.74605-1-jiaxun.yang@flygoat.com>
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On Mon, Jan 13, 2020 at 10:07:04PM +0800, Jiaxun Yang wrote:
> For MIPS chips that support coherentio DMA, it's always safe
> to make DMA requests cached.

For DMA coherent devices pgprot_dmacoherent isn't even used, so this
doesn't make sense.