[U-Boot] [PATCH V3 07/13] mmc: tmio: Do not set divider to 1 in DDR mode

Marek Vasut marek.vasut at gmail.com
Fri Nov 2 15:03:22 UTC 2018


The TMIO core has a quirk where divider == 1 must not be set in DDR modes.
Handle this by setting divider to 2, as suggested in the documentation.

Signed-off-by: Marek Vasut <marek.vasut+renesas at gmail.com>
Cc: Masahiro Yamada <yamada.masahiro at socionext.com>
---
V2: No change
V3: No change
---
 drivers/mmc/tmio-common.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/mmc/tmio-common.c b/drivers/mmc/tmio-common.c
index 3ba2f07460..424b60ce52 100644
--- a/drivers/mmc/tmio-common.c
+++ b/drivers/mmc/tmio-common.c
@@ -574,6 +574,10 @@ static void tmio_sd_set_clk_rate(struct tmio_sd_priv *priv,
 
 	divisor = DIV_ROUND_UP(mclk, mmc->clock);
 
+	/* Do not set divider to 0xff in DDR mode */
+	if (mmc->ddr_mode && (divisor == 1))
+		divisor = 2;
+
 	if (divisor <= 1)
 		val = (priv->caps & TMIO_SD_CAP_RCAR) ?
 		      TMIO_SD_CLKCTL_RCAR_DIV1 : TMIO_SD_CLKCTL_DIV1;
-- 
2.18.0



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