Add Reset Management Unit (RMU) support for Actions Semi Owl SoCs. Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> --- drivers/clk/actions/Kconfig | 1 + drivers/clk/actions/Makefile | 1 + drivers/clk/actions/owl-common.h | 2 + drivers/clk/actions/owl-reset.c | 66 ++++++++++++++++++++++++++++++++ drivers/clk/actions/owl-reset.h | 31 +++++++++++++++ 5 files changed, 101 insertions(+) create mode 100644 drivers/clk/actions/owl-reset.c create mode 100644 drivers/clk/actions/owl-reset.h diff --git a/drivers/clk/actions/Kconfig b/drivers/clk/actions/Kconfig index dc38c85a4833..04f0a6355726 100644 --- a/drivers/clk/actions/Kconfig +++ b/drivers/clk/actions/Kconfig @@ -2,6 +2,7 @@ config CLK_ACTIONS 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 78c17d56f991..ccfdf9781cef 100644 --- a/drivers/clk/actions/Makefile +++ b/drivers/clk/actions/Makefile @@ -7,6 +7,7 @@ clk-owl-y += owl-divider.o 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 56f01f7774aa..5a866a8b913d 100644 --- a/drivers/clk/actions/owl-common.h +++ b/drivers/clk/actions/owl-common.h @@ -26,6 +26,8 @@ struct owl_clk_desc { 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 000000000000..203f8f34a8d4 --- /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@xxxxxxxxxx> + +#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 000000000000..10f5774979a6 --- /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@xxxxxxxxxx> + +#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_ */ -- 2.17.1