Re: [PATCH v2 3/3] spi: spi-davinci: convert to DMA engine API

From: Vinod Koul
Date: Tue Aug 21 2012 - 23:43:50 EST


On Tue, 2012-08-21 at 14:43 -0400, Matt Porter wrote:
> Removes use of the DaVinci EDMA private DMA API and replaces
> it with use of the DMA engine API.
>
> Signed-off-by: Matt Porter <mporter@xxxxxx>
> ---

> + struct dma_slave_config dma_rx_conf = {
> + .direction = DMA_DEV_TO_MEM,
> + .src_addr = (unsigned long)dspi->pbase + SPIBUF,
> + .src_addr_width = data_type,
> + .src_maxburst = 1,
what does 1 mean in this context? We define as number of units that
needs to be transfered, so are you sure that you want only one unit to
be dma'ed in a single burst. that seems like killing your dmac,
shouldn't you be using larger bursts for a better dma performance?


--
~Vinod

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