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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Fri, 31 Mar 2023 11:01:51 +0200
Message-ID: <CACRpkdbMry_UUYN1MuXTUpRXV+Tj9RSDvN-iBdvR8hDfkTaX4w@mail.gmail.com>
Subject: Re: [PATCH 15/21] ARM: dma-mapping: always invalidate WT caches
 before DMA
To:     Arnd Bergmann <arnd@kernel.org>
Cc:     linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
        Vineet Gupta <vgupta@kernel.org>,
        Russell King <linux@armlinux.org.uk>,
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On Mon, Mar 27, 2023 at 2:16=E2=80=AFPM Arnd Bergmann <arnd@kernel.org> wro=
te:

> From: Arnd Bergmann <arnd@arndb.de>
>
> Most ARM CPUs can have write-back caches and that require
> cache management to be done in the dma_sync_*_for_device()
> operation. This is typically done in both writeback and
> writethrough mode.
>
> The cache-v4.S (arm720/740/7tdmi/9tdmi) and cache-v4wt.S
> (arm920t, arm940t) implementations are the exception here,
> and only do the cache management after the DMA is complete,
> in the dma_sync_*_for_cpu() operation.
>
> Change this for consistency with the other platforms. This
> should have no user visible effect.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Looks good to me.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij