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Combine these into > one write operation to reduce bus overhead. > Additionally, avoid redundant channel starts in xilinx_dma_start_transfer() > and xilinx_mcdma_start_transfer() by only calling xilinx_dma_start() when > the channel is actually idle. > > Tested-by: Folker Schwesinger > Signed-off-by: Suraj Gupta > Co-developed-by: Srinivas Neeli > Signed-off-by: Srinivas Neeli Reviewed-by: Radhey Shyam Pandey Thanks! > --- > drivers/dma/xilinx/xilinx_dma.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c > index 6e7b183cb499..829601d8a16f 100644 > --- a/drivers/dma/xilinx/xilinx_dma.c > +++ b/drivers/dma/xilinx/xilinx_dma.c > @@ -1603,7 +1603,6 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan) > reg &= ~XILINX_DMA_CR_COALESCE_MAX; > reg |= chan->desc_pendingcount << > XILINX_DMA_CR_COALESCE_SHIFT; > - dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg); > } > > if (chan->has_sg && list_empty(&chan->active_list)) > @@ -1614,7 +1613,8 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan) > reg |= XILINX_DMA_DMAXR_ALL_IRQ_MASK; > dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg); > > - xilinx_dma_start(chan); > + if (chan->idle) > + xilinx_dma_start(chan); > > if (chan->err) > return; > @@ -1703,7 +1703,8 @@ static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan) > reg |= XILINX_MCDMA_CR_RUNSTOP_MASK; > dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg); > > - xilinx_dma_start(chan); > + if (chan->idle) > + xilinx_dma_start(chan); > > if (chan->err) > return;