Re: [PATCH] mmc: dw_mmc: Reset DMA before enabling IDMAC

From: Doug Anderson
Date: Mon Oct 06 2014 - 14:11:12 EST


Sonny,

On Mon, Oct 6, 2014 at 10:53 AM, Sonny Rao <sonnyrao@xxxxxxxxxxxx> wrote:
> We've already got a reset of DMA after it's done. Add one before we
> start DMA too. This fixes a data corruption on Rockchip SoCs which
> will get bad data when doing a DMA transfer after doing a PIO transfer.
>
> We tested this on an Exynos 5800 with HS200 and didn't notice any
> difference in sequential read throughput.
>
> Signed-off-by: Sonny Rao <sonnyrao@xxxxxxxxxxxx>
> Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx>
> ---
> drivers/mmc/host/dw_mmc.c | 4 ++++
> 1 file changed, 4 insertions(+)

Reviewed-by: Doug Anderson <dianders@xxxxxxxxxxxx>
Tested-by: Doug Anderson <dianders@xxxxxxxxxxxx>
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