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Ref spec section [...] > > "It is thus essential for the Arm platform to program them before any DMA > request is triggered to the SDMA, otherwise an unpredictable combination > of channels may be started." SDMA hardware configuration is postponed to the transfer phase, so enabling the DMA request too early may cause unpredictable channel activation. Then keep dma request disabled before dma transfer setup. Frank > > Signed-off-by: Carlos Song > Signed-off-by: Robin Gong > --- > drivers/spi/spi-imx.c | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c > index cd40db61d8d1..765ea507dd8d 100644 > --- a/drivers/spi/spi-imx.c > +++ b/drivers/spi/spi-imx.c > @@ -529,9 +529,15 @@ static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx) > { > u32 reg; > > - reg = readl(spi_imx->base + MX51_ECSPI_CTRL); > - reg |= MX51_ECSPI_CTRL_XCH; > - writel(reg, spi_imx->base + MX51_ECSPI_CTRL); > + if (spi_imx->usedma) { > + reg = readl(spi_imx->base + MX51_ECSPI_DMA); > + reg |= MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN; > + writel(reg, spi_imx->base + MX51_ECSPI_DMA); > + } else { > + reg = readl(spi_imx->base + MX51_ECSPI_CTRL); > + reg |= MX51_ECSPI_CTRL_XCH; > + writel(reg, spi_imx->base + MX51_ECSPI_CTRL); > + } > } > > static void mx51_ecspi_disable(struct spi_imx_data *spi_imx) > @@ -772,7 +778,6 @@ static void mx51_setup_wml(struct spi_imx_data *spi_imx) > writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) | > MX51_ECSPI_DMA_TX_WML(tx_wml) | > MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) | > - MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN | > MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA); > } > > @@ -1539,6 +1544,8 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx, > reinit_completion(&spi_imx->dma_tx_completion); > dma_async_issue_pending(controller->dma_tx); > > + spi_imx->devtype_data->trigger(spi_imx); > + > transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len); > > /* Wait SDMA to finish the data transfer.*/ > -- > 2.34.1 >