[PATCH 15/21] ARM: dma-mapping: always invalidate WT caches before DMA

Linus Walleij linus.walleij at linaro.org
Fri Mar 31 02:01:51 PDT 2023


On Mon, Mar 27, 2023 at 2:16 PM Arnd Bergmann <arnd at kernel.org> wrote:

> From: Arnd Bergmann <arnd at 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 at arndb.de>

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

Yours,
Linus Walleij



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