clk: actions: Add Actions Semi Owl SoCs Reset Management Unit support
Add Reset Management Unit (RMU) support for Actions Semi Owl SoCs.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
diff --git a/drivers/clk/actions/Kconfig b/drivers/clk/actions/Kconfig
index dc38c85..04f0a63 100644
--- a/drivers/clk/actions/Kconfig
+++ b/drivers/clk/actions/Kconfig
@@ -2,6 +2,7 @@
bool "Clock driver for Actions Semi SoCs"
depends on ARCH_ACTIONS || COMPILE_TEST
select REGMAP_MMIO
+ select RESET_CONTROLLER
default ARCH_ACTIONS
if CLK_ACTIONS
diff --git a/drivers/clk/actions/Makefile b/drivers/clk/actions/Makefile
index 78c17d5..ccfdf97 100644
--- a/drivers/clk/actions/Makefile
+++ b/drivers/clk/actions/Makefile
@@ -7,6 +7,7 @@
clk-owl-y += owl-factor.o
clk-owl-y += owl-composite.o
clk-owl-y += owl-pll.o
+clk-owl-y += owl-reset.o
# SoC support
obj-$(CONFIG_CLK_OWL_S700) += owl-s700.o
diff --git a/drivers/clk/actions/owl-common.h b/drivers/clk/actions/owl-common.h
index 56f01f7..5a866a8 100644
--- a/drivers/clk/actions/owl-common.h
+++ b/drivers/clk/actions/owl-common.h
@@ -26,6 +26,8 @@
struct owl_clk_common **clks;
unsigned long num_clks;
struct clk_hw_onecell_data *hw_clks;
+ const struct owl_reset_map *resets;
+ unsigned long num_resets;
struct regmap *regmap;
};
diff --git a/drivers/clk/actions/owl-reset.c b/drivers/clk/actions/owl-reset.c
new file mode 100644
index 0000000..203f8f3
--- /dev/null
+++ b/drivers/clk/actions/owl-reset.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+//
+// Actions Semi Owl SoCs Reset Management Unit driver
+//
+// Copyright (c) 2018 Linaro Ltd.
+// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+
+#include <linux/delay.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+#include "owl-reset.h"
+
+static int owl_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct owl_reset *reset = to_owl_reset(rcdev);
+ const struct owl_reset_map *map = &reset->reset_map[id];
+
+ return regmap_update_bits(reset->regmap, map->reg, map->bit, 0);
+}
+
+static int owl_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct owl_reset *reset = to_owl_reset(rcdev);
+ const struct owl_reset_map *map = &reset->reset_map[id];
+
+ return regmap_update_bits(reset->regmap, map->reg, map->bit, map->bit);
+}
+
+static int owl_reset_reset(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ owl_reset_assert(rcdev, id);
+ udelay(1);
+ owl_reset_deassert(rcdev, id);
+
+ return 0;
+}
+
+static int owl_reset_status(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct owl_reset *reset = to_owl_reset(rcdev);
+ const struct owl_reset_map *map = &reset->reset_map[id];
+ u32 reg;
+ int ret;
+
+ ret = regmap_read(reset->regmap, map->reg, ®);
+ if (ret)
+ return ret;
+
+ /*
+ * The reset control API expects 0 if reset is not asserted,
+ * which is the opposite of what our hardware uses.
+ */
+ return !(map->bit & reg);
+}
+
+const struct reset_control_ops owl_reset_ops = {
+ .assert = owl_reset_assert,
+ .deassert = owl_reset_deassert,
+ .reset = owl_reset_reset,
+ .status = owl_reset_status,
+};
diff --git a/drivers/clk/actions/owl-reset.h b/drivers/clk/actions/owl-reset.h
new file mode 100644
index 0000000..10f5774
--- /dev/null
+++ b/drivers/clk/actions/owl-reset.h
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+//
+// Actions Semi Owl SoCs Reset Management Unit driver
+//
+// Copyright (c) 2018 Linaro Ltd.
+// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+
+#ifndef _OWL_RESET_H_
+#define _OWL_RESET_H_
+
+#include <linux/reset-controller.h>
+
+struct owl_reset_map {
+ u32 reg;
+ u32 bit;
+};
+
+struct owl_reset {
+ struct reset_controller_dev rcdev;
+ const struct owl_reset_map *reset_map;
+ struct regmap *regmap;
+};
+
+static inline struct owl_reset *to_owl_reset(struct reset_controller_dev *rcdev)
+{
+ return container_of(rcdev, struct owl_reset, rcdev);
+}
+
+extern const struct reset_control_ops owl_reset_ops;
+
+#endif /* _OWL_RESET_H_ */