Message-ID: <54f204eb-79b5-5c1c-fffb-696939644d8c@arm.com>
Date:   Tue, 21 Feb 2023 19:35:05 +0000
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Subject: Re: [PATCH 4/7] dma-mapping: Always provide dma_default_coherent
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To:     Christoph Hellwig <hch@lst.de>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc:     linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org, tsbogend@alpha.franken.de,
        mpe@ellerman.id.au, paul.walmsley@sifive.com, palmer@dabbelt.com,
        robh+dt@kernel.org, m.szyprowski@samsung.com
References: <20230221124613.2859-1-jiaxun.yang@flygoat.com>
 <20230221124613.2859-5-jiaxun.yang@flygoat.com>
 <20230221175813.GC15247@lst.de>
From:   Robin Murphy <robin.murphy@arm.com>
In-Reply-To: <20230221175813.GC15247@lst.de>
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On 2023-02-21 17:58, Christoph Hellwig wrote:
> On Tue, Feb 21, 2023 at 12:46:10PM +0000, Jiaxun Yang wrote:
>> dma_default_coherent can be useful for determine default coherency
>> even on arches without noncoherent support.
> 
> How?

Indeed, "default" is conceptually meaningless when there is no possible 
alternative :/

Robin.