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Date:   Wed, 29 Mar 2023 21:16:10 +0100
From:   Conor Dooley <conor@kernel.org>
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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Subject: Re: [PATCH 09/21] riscv: dma-mapping: skip invalidation before
 bidirectional DMA
Message-ID: <764e8d2f-ed98-49dc-8fdb-112d59359148@spud>
References: <20230327121317.4081816-1-arnd@kernel.org>
 <20230327121317.4081816-10-arnd@kernel.org>
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On Mon, Mar 27, 2023 at 02:13:05PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>=20
> For a DMA_BIDIRECTIONAL transfer, the caches have to be cleaned
> first to let the device see data written by the CPU, and invalidated
> after the transfer to let the CPU see data written by the device.
>=20
> riscv also invalidates the caches before the transfer, which does
> not appear to serve any purpose.

Rationale makes sense to me..
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Thanks for working on all of this Arnd!

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