Re: [PATCH v4 11/18] dmaengine: dma-jz4780: Add missing residue DTC mask

Vinod
2018-08-27T05:00:57Z

On 07-08-18, 13:42, Paul Cercueil wrote:
> From: Daniel Silsby <dansilsby@gmail.com>
>
> The 'dtc' word in jz DMA descriptors contains two fields: The
> lowest 24 bits are the transfer count, and upper 8 bits are the DOA
> offset to next descriptor. The upper 8 bits are now correctly masked
> off when computing residue in jz4780_dma_desc_residue(). Note that
> reads of the DTCn hardware reg are automatically masked this way.
>
> Signed-off-by: Daniel Silsby <dansilsby@gmail.com>
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Tested-by: Mathieu Malaterre <malat@debian.org>
> ---
> drivers/dma/dma-jz4780.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> v2: No change
>
> v3: No change
>
> v4: Add my Signed-off-by
>
> diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c
> index 3a4d0a4b550d..a4292ac4c686 100644
> --- a/drivers/dma/dma-jz4780.c
> +++ b/drivers/dma/dma-jz4780.c
> @@ -616,7 +616,8 @@ static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan,
> residue = 0;
>
> for (i = next_sg; i < desc->count; i++)
> - residue += desc->desc[i].dtc << jzchan->transfer_shift;
> + residue += (desc->desc[i].dtc & 0xffffff) <<

GENMASK(23, 0) please.

--
~Vinod