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    SubjectRe: [PATCH 09/21] riscv: dma-mapping: skip invalidation before bidirectional DMA
    On Mon, Mar 27, 2023 at 02:13:05PM +0200, Arnd Bergmann wrote:
    > From: Arnd Bergmann <arnd@arndb.de>
    >
    > 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.
    >
    > 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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