On some SoCs, depending on the boot device, the MMC clock block may be left in a weird state by the ROM code, in which no decent clock may be provided. Reset the related register to make sure a sane MMC clock is ready for the controller.
Reviewed-by: Neil Armstrong narmstrong@baylibre.com Tested-by: Anand Moon linux.amoon@gmail.com Signed-off-by: Jerome Brunet jbrunet@baylibre.com --- drivers/clk/meson/axg.c | 7 +++++++ drivers/clk/meson/g12a.c | 7 +++++++ drivers/clk/meson/gxbb.c | 7 +++++++ 3 files changed, 21 insertions(+)
diff --git a/drivers/clk/meson/axg.c b/drivers/clk/meson/axg.c index 32cbf752aed8..0ba6c303e122 100644 --- a/drivers/clk/meson/axg.c +++ b/drivers/clk/meson/axg.c @@ -290,6 +290,13 @@ static int meson_clk_probe(struct udevice *dev) if (IS_ERR(priv->map)) return PTR_ERR(priv->map);
+ /* + * Depending on the boot src, the state of the MMC clock might + * be different. Reset it to make sure we won't get stuck + */ + regmap_write(priv->map, HHI_NAND_CLK_CNTL, 0); + regmap_write(priv->map, HHI_SD_EMMC_CLK_CNTL, 0); + debug("meson-clk-axg: probed\n");
return 0; diff --git a/drivers/clk/meson/g12a.c b/drivers/clk/meson/g12a.c index 1b2523bbf1fe..03d885d986b8 100644 --- a/drivers/clk/meson/g12a.c +++ b/drivers/clk/meson/g12a.c @@ -976,6 +976,13 @@ static int meson_clk_probe(struct udevice *dev) if (IS_ERR(priv->map)) return PTR_ERR(priv->map);
+ /* + * Depending on the boot src, the state of the MMC clock might + * be different. Reset it to make sure we won't get stuck + */ + regmap_write(priv->map, HHI_NAND_CLK_CNTL, 0); + regmap_write(priv->map, HHI_SD_EMMC_CLK_CNTL, 0); + debug("meson-clk-g12a: probed\n");
return 0; diff --git a/drivers/clk/meson/gxbb.c b/drivers/clk/meson/gxbb.c index abb5337e7829..aedba991603f 100644 --- a/drivers/clk/meson/gxbb.c +++ b/drivers/clk/meson/gxbb.c @@ -886,6 +886,13 @@ static int meson_clk_probe(struct udevice *dev) if (IS_ERR(priv->map)) return PTR_ERR(priv->map);
+ /* + * Depending on the boot src, the state of the MMC clock might + * be different. Reset it to make sure we won't get stuck + */ + regmap_write(priv->map, HHI_NAND_CLK_CNTL, 0); + regmap_write(priv->map, HHI_SD_EMMC_CLK_CNTL, 0); + debug("meson-clk: probed\n");
return 0;