[PATCH] mmc: tmio: Disable 1/1024 clock divider on Renesas R-Car platforms

[Marek Vasut]

The R-Car Gen3 SD_CLK_CTRL register does not use BIT(16) to implement
divider 1/1024, instead BIT(16) is reserved bit and divider 1/1024 is
not supported. The divider 1/1024 is specific to Socionext variant of
the IP, as is indicated by Linux commit:

0196c8db8363 ("mmc: tmio: move tmio_mmc_set_clock() to platform hook")
"
Socionext (and Panasonic) uses bit 10 (CLKSEL) for 1/1.  Also, newer
versions of UniPhier SoC variants use bit 16 for 1/1024.
"

Do not set the TMIO_SD_CAP_DIV1024 on Renesas R-Car platforms even if
the IP VERSION register does exist, and indicates IP version is newer
or equal to version 1.0 . The IP version 1.0 or newer does not imply
presence of the 1/1024 divider.

Since the TMIO driver is used exactly by two supported platforms, that
is Renesas R-Car and Socionext UniPhier, it is OK to check whether the
TMIO_SD_CAP_RCAR capability is not set to identify the UniPhier platform
and add the capability only on that platform.

Fixes: 58c35b17aa8f ("mmc: matsushita-common: Always check controller version")
Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
---
Cc: Jaehoon Chung <jh80.chung at samsung.com>
Cc: Nobuhiro Iwamatsu <iwamatsu at nigauri.org>
Cc: Paul Barker <paul.barker.ct at bp.renesas.com>
Cc: Peng Fan <peng.fan at nxp.com>
---
 drivers/mmc/tmio-common.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/tmio-common.c b/drivers/mmc/tmio-common.c
index 83eaf361f0c..890c496b535 100644
--- a/drivers/mmc/tmio-common.c
+++ b/drivers/mmc/tmio-common.c
@@ -759,7 +759,8 @@ int tmio_sd_probe(struct udevice *dev, u32 quirks)
 	dev_dbg(dev, "version %x\n", priv->version);
 	if (priv->version >= 0x10) {
 		priv->caps |= TMIO_SD_CAP_DMA_INTERNAL;
-		priv->caps |= TMIO_SD_CAP_DIV1024;
+		if (!(priv->caps & TMIO_SD_CAP_RCAR))
+			priv->caps |= TMIO_SD_CAP_DIV1024;
 	}
 
 	if (fdt_get_property(gd->fdt_blob, dev_of_offset(dev), "non-removable",
-- 
2.42.0