Re: [PATCH 07/14] dmaengine: dma-jz4780: Enable Fast DMA to the AIC

From: PrasannaKumar Muralidharan
Date: Wed Jul 04 2018 - 13:00:50 EST


On 3 July 2018 at 18:02, Paul Cercueil <paul@xxxxxxxxxxxxxxx> wrote:
> With the fast DMA bit set, the DMA will transfer twice as much data
> per clock period to the AIC, so there is little point not to set it.
>
> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> ---
> drivers/dma/dma-jz4780.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c
> index 922e4031e70e..7ee2c121948f 100644
> --- a/drivers/dma/dma-jz4780.c
> +++ b/drivers/dma/dma-jz4780.c
> @@ -52,6 +52,7 @@
> #define JZ_DMA_DMAC_DMAE BIT(0)
> #define JZ_DMA_DMAC_AR BIT(2)
> #define JZ_DMA_DMAC_HLT BIT(3)
> +#define JZ_DMA_DMAC_FAIC BIT(27)
> #define JZ_DMA_DMAC_FMSC BIT(31)
>
> #define JZ_DMA_DRT_AUTO 0x8
> @@ -929,8 +930,8 @@ static int jz4780_dma_probe(struct platform_device *pdev)
> * Also set the FMSC bit - it increases MSC performance, so it makes
> * little sense not to enable it.
> */
> - jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMAC,
> - JZ_DMA_DMAC_DMAE | JZ_DMA_DMAC_FMSC);
> + jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMAC, JZ_DMA_DMAC_DMAE |
> + JZ_DMA_DMAC_FAIC | JZ_DMA_DMAC_FMSC);
>
> if (jzdma->version == ID_JZ4780)
> jz4780_dma_ctrl_writel(jzdma, JZ_DMA_REG_DMACP, 0);
> --
> 2.18.0
>
>

Reviewed-by: PrasannaKumar Muralidharan <prasannatsmkumar@xxxxxxxxx>.