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Date:   Fri, 27 Mar 2020 14:26:34 +0800
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Subject: Re: [PATCH v2 2/3] MIPS: Loongson: Add DMA support for 7A1000
To:     Christoph Hellwig <hch@infradead.org>,
        Tiezhu Yang <yangtiezhu@loongson.cn>
CC:     Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Huacai Chen <chenhc@lemote.com>, linux-mips@vger.kernel.org,
        linux-kernel@vger.kernel.org, Xuefeng Li <lixuefeng@loongson.cn>
From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-ID: <7786800D-3B37-4F0D-8E55-17F595D97EF2@flygoat.com>
Sender: linux-kernel-owner@vger.kernel.org
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=E4=BA=8E 2020=E5=B9=B43=E6=9C=8825=E6=97=A5 GMT+08:00 =E4=B8=8B=E5=8D=889=
:27:56, Christoph Hellwig <hch@infradead=2Eorg> =E5=86=99=E5=88=B0:
>On Mon, Mar 23, 2020 at 10:59:14AM +0800, Tiezhu Yang wrote:
>> Implement __phys_to_dma() and __dma_to_phys() according to the
>> node id offset in the 7A1000 DMA route config register=2E
>
>Can you please try to just use the dma_pfn_offset field in struct
>device
>for all loongson platforms?  I'm pretty sure I asked for that last time
>around=2E=2E

Here we have a problem that dma_pfn_offset doesn't fit our platform=2E

We have multiple dma-ranges that translate in to different address and
dma_pfn_offset can only handle single range=20
with fixed offset=2E

Thanks=2E

--=20
Jiaxun Yang