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spi: imx: keep dma request disabled before dma transfer setup

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Since sdma hardware configure postpone to transfer phase, have to disable
dma request before dma transfer setup because there is a hardware
limitation on sdma event enable(ENBLn) as below:

"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."

Signed-off-by: Carlos Song <carlos.song@nxp.com>
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Link: https://patch.msgid.link/20251024055320.408482-1-carlos.song@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Robin Gong
2025-10-24 13:53:20 +08:00
committed by Mark Brown
parent 3cd2018e15
commit 86d57d9c07
1 changed files with 11 additions and 4 deletions
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15
drivers/spi/spi-imx.c
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@@ -519,9 +519,15 @@ 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)
@@ -759,7 +765,6 @@ 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);
}
@@ -1520,6 +1525,8 @@ 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.*/