[PATCH V2 05/15] mmc: sdhci-esdhci-imx: disable DLL delay line settings explicitly

[Dong Aisheng]

From: Dong Aisheng <aisheng.dong at freescale.com>

Disable DLL delay line settings explicitly during driver initialization
in case ROM/uBoot had set an invalid delay.
e.g. MX6DL ROM has set the default delay line(DLLCTRL) to 0x1000021,
the uSDHC clock timing will become marginal when works on DDR mode
due to default delay and will possibly see CRC errors in case the board
is not perfectly designed on the eMMC chip layout.

Acked-by: Adrian Hunter <adrian.hunter at intel.com>
Signed-off-by: Dong Aisheng <aisheng.dong at nxp.com>
---
 drivers/mmc/host/sdhci-esdhc-imx.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 91c6a6864e15..874d5105f83c 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -1187,6 +1187,9 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev)
 		*/
 		writel(readl(host->ioaddr + 0x6c) | BIT(7),
 			host->ioaddr + 0x6c);
+
+		/* disable DLL_CTRL delay line settings */
+		writel(0x0, host->ioaddr + ESDHC_DLL_CTRL);
 	}
 
 	if (imx_data->socdata->flags & ESDHC_FLAG_MAN_TUNING)
-- 
1.9.1