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From:   Rob Herring <robh+dt@kernel.org>
Date:   Tue, 28 Mar 2023 09:15:20 -0500
Message-ID: <CAL_JsqKxJ-u4owKhY1tSiDyBo0=92iQoJM0G6TAZ7BSNpJAZAw@mail.gmail.com>
Subject: Re: [PATCH v3 1/4] of: address: Fix default coherency for MIPS
To:     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,
        hch@lst.de, m.szyprowski@samsung.com, robin.murphy@arm.com,
        linux-riscv@lists.infradead.org
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On Tue, Mar 21, 2023 at 6:08=E2=80=AFAM Jiaxun Yang <jiaxun.yang@flygoat.co=
m> wrote:
>
> DT-based MIPS doesn't use OF_DMA_DEFAULT_COHERENT, but
> might override the system-wide default at runtime.
>
> Use dma_default_coherent to override default coherence for
> MIPS.
>

I assume you want this tagged for stable? Otherwise, I don't
understand why you add this here and then remove in patch 4.

> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> ---
>  drivers/of/address.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 4c0b169ef9bf..c105d66a1fa4 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -1105,6 +1105,14 @@ bool of_dma_is_coherent(struct device_node *np)
>         struct device_node *node;
>         bool is_coherent =3D IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT);
>
> +       /*
> +        * DT-based MIPS doesn't use OF_DMA_DEFAULT_COHERENT, but
> +        * might override the system-wide default at runtime.
> +        */
> +#if defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
> +       is_coherent =3D dma_default_coherent;
> +#endif
> +
>         node =3D of_node_get(np);
>
>         while (node) {
> --
> 2.37.1 (Apple Git-137.1)
>