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However, it also programs > that unencoded value directly into the hardware fields. A value of 256 > therefore overflows the 8-bit fields and can cause AXI decode errors. > > Subtract one only when constructing hardware descriptors, while keeping > the actual value for dma_device.max_burst. > > Fixes: c454d16a7d5a ("dmaengine: dw-axi-dmac: Burst length settings") > Signed-off-by: Jia Wang > --- suggest switch to use FIELD_PREP() later Reviewed-by: Frank Li > drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c > index eebed2474210..742e08cfab43 100644 > --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c > +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c > @@ -706,7 +706,7 @@ static int dw_axi_dma_set_hw_desc(struct axi_dma_chan *chan, > ctlhi = CH_CTL_H_LLI_VALID; > > if (chan->chip->dw->hdata->restrict_axi_burst_len) { > - burst_len = chan->chip->dw->hdata->axi_rw_burst_len; > + burst_len = chan->chip->dw->hdata->axi_rw_burst_len - 1; > ctlhi |= CH_CTL_H_ARLEN_EN | CH_CTL_H_AWLEN_EN | > burst_len << CH_CTL_H_ARLEN_POS | > burst_len << CH_CTL_H_AWLEN_POS; > @@ -975,7 +975,7 @@ dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr, > > reg = CH_CTL_H_LLI_VALID; > if (chan->chip->dw->hdata->restrict_axi_burst_len) { > - u32 burst_len = chan->chip->dw->hdata->axi_rw_burst_len; > + u32 burst_len = chan->chip->dw->hdata->axi_rw_burst_len - 1; > > reg |= (CH_CTL_H_ARLEN_EN | > burst_len << CH_CTL_H_ARLEN_POS | > > -- > 2.34.1 >