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Subject: Re: [PATCH 0/7] MIPS DMA coherence fixes
From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
In-Reply-To: <20230221175423.GA15247@lst.de>
Date:   Tue, 21 Feb 2023 18:15:51 +0000
Cc:     "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org>,
        linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        mpe@ellerman.id.au, paul.walmsley@sifive.com, palmer@dabbelt.com,
        Rob Herring <robh+dt@kernel.org>, m.szyprowski@samsung.com,
        robin.murphy@arm.com
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Message-Id: <A8AC22A0-E883-4D9B-A629-5A3721B976C5@flygoat.com>
References: <20230221124613.2859-1-jiaxun.yang@flygoat.com>
 <20230221175423.GA15247@lst.de>
To:     Christoph Hellwig <hch@lst.de>
Precedence: bulk


> 2023=E5=B9=B42=E6=9C=8821=E6=97=A5 17:54=EF=BC=8CChristoph Hellwig =
<hch@lst.de> =E5=86=99=E9=81=93=EF=BC=9A
>=20
> Can you explain the motivation here?  Also why riscv patches are at
> the end of a mips f=D1=96xes series?

Ah sorry for any confusion.

So the main purpose of this patch is to fix MIPS=E2=80=99s broken =
per-device coherency.
To be more precise, we want to be able to control the default coherency =
for all devices probed from
devicetree in early boot code.

To achieve that I decided to reuse dma_default_coherent to set default =
coherency for devicetree.
And all later patches are severing for this purpose.

Thanks
- Jiaxun=