From b3d69aa596599c7c940f7ad463c04b693589ff9a Mon Sep 17 00:00:00 2001
From: Jerome Brunet <jbrunet@baylibre.com>
Date: Thu, 5 Mar 2020 12:12:37 +0100
Subject: [PATCH] clk: meson: reset mmc clock on probe
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>
Signed-off-by: Neil Armstrong <narmstrong@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 7035b59a13..4b0028d04b 100644
--- a/drivers/clk/meson/axg.c
+++ b/drivers/clk/meson/axg.c
@@ -291,6 +291,13 @@ 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 cada80e6b5..c1976aa1ef 100644
--- a/drivers/clk/meson/g12a.c
+++ b/drivers/clk/meson/g12a.c
@@ -978,6 +978,13 @@ 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 e781e08d9d..5ef4dd794d 100644
--- a/drivers/clk/meson/gxbb.c
+++ b/drivers/clk/meson/gxbb.c
@@ -887,6 +887,13 @@ 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;
--
2.39.5