From: Owen Chen owen.chen@mediatek.com
On both MT8183 & MT6765, there add "set/clr" register for each clkmux setting, and one update register to trigger value change. It is designed to prevent read-modify-write racing issue. The sw design need to add a new API to handle this hw change with a new mtk_clk_mux/mtk_mux struct in new file "clk-mux.c", "clk-mux.h".
Signed-off-by: Owen Chen owen.chen@mediatek.com Signed-off-by: Weiyi Lu weiyi.lu@mediatek.com --- drivers/clk/mediatek/Makefile | 3 +- drivers/clk/mediatek/clk-mux.c | 229 +++++++++++++++++++++++++++++++++ drivers/clk/mediatek/clk-mux.h | 101 +++++++++++++++ 3 files changed, 332 insertions(+), 1 deletion(-) create mode 100644 drivers/clk/mediatek/clk-mux.c create mode 100644 drivers/clk/mediatek/clk-mux.h
diff --git a/drivers/clk/mediatek/Makefile b/drivers/clk/mediatek/Makefile index 844b55d2770d..00e4d405231e 100644 --- a/drivers/clk/mediatek/Makefile +++ b/drivers/clk/mediatek/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_COMMON_CLK_MEDIATEK) += clk-mtk.o clk-pll.o clk-gate.o clk-apmixed.o clk-cpumux.o reset.o +obj-$(CONFIG_COMMON_CLK_MEDIATEK) += clk-mtk.o clk-pll.o clk-gate.o clk-apmixed.o clk-cpumux.o reset.o clk-mux.o + obj-$(CONFIG_COMMON_CLK_MT6797) += clk-mt6797.o obj-$(CONFIG_COMMON_CLK_MT6797_IMGSYS) += clk-mt6797-img.o obj-$(CONFIG_COMMON_CLK_MT6797_MMSYS) += clk-mt6797-mm.o diff --git a/drivers/clk/mediatek/clk-mux.c b/drivers/clk/mediatek/clk-mux.c new file mode 100644 index 000000000000..efbbb35eb185 --- /dev/null +++ b/drivers/clk/mediatek/clk-mux.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018 MediaTek Inc. + * Author: Owen Chen owen.chen@mediatek.com + */ + +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/slab.h> +#include <linux/mfd/syscon.h> + +#include "clk-mtk.h" +#include "clk-mux.h" + +static inline struct mtk_clk_mux *to_mtk_clk_mux(struct clk_hw *hw) +{ + return container_of(hw, struct mtk_clk_mux, hw); +} + +static int mtk_clk_mux_enable(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 mask = BIT(mux->gate_shift); + + return regmap_update_bits(mux->regmap, mux->mux_ofs, mask, ~mask); +} + +static void mtk_clk_mux_disable(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 mask = BIT(mux->gate_shift); + + regmap_update_bits(mux->regmap, mux->mux_ofs, mask, mask); +} + +static int mtk_clk_mux_enable_setclr(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + + return regmap_write(mux->regmap, mux->mux_clr_ofs, + BIT(mux->gate_shift)); +} + +static void mtk_clk_mux_disable_setclr(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + + regmap_write(mux->regmap, mux->mux_set_ofs, BIT(mux->gate_shift)); +} + +static int mtk_clk_mux_is_enabled(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 val; + + regmap_read(mux->regmap, mux->mux_ofs, &val); + + return (val & BIT(mux->gate_shift)) == 0; +} + +static u8 mtk_clk_mux_get_parent(struct clk_hw *hw) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 mask = GENMASK(mux->mux_width - 1, 0); + u32 val; + + regmap_read(mux->regmap, mux->mux_ofs, &val); + val = (val >> mux->mux_shift) & mask; + + return val; +} + +static int mtk_clk_mux_set_parent_lock(struct clk_hw *hw, u8 index) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 mask = GENMASK(mux->mux_width - 1, 0); + unsigned long flags; + + if (mux->lock) + spin_lock_irqsave(mux->lock, flags); + else + __acquire(mux->lock); + + regmap_update_bits(mux->regmap, mux->mux_ofs, mask, + index << mux->mux_shift); + + if (mux->lock) + spin_unlock_irqrestore(mux->lock, flags); + else + __release(mux->lock); + + return 0; +} + +static int mtk_clk_mux_set_parent_setclr_lock(struct clk_hw *hw, u8 index) +{ + struct mtk_clk_mux *mux = to_mtk_clk_mux(hw); + u32 mask = GENMASK(mux->mux_width - 1, 0); + u32 val, orig; + unsigned long flags; + + if (mux->lock) + spin_lock_irqsave(mux->lock, flags); + else + __acquire(mux->lock); + + regmap_read(mux->regmap, mux->mux_ofs, &orig); + val = (orig & ~(mask << mux->mux_shift)) | (index << mux->mux_shift); + + if (val != orig) { + regmap_write(mux->regmap, mux->mux_clr_ofs, + mask << mux->mux_shift); + regmap_write(mux->regmap, mux->mux_set_ofs, + index << mux->mux_shift); + + if (mux->upd_shift >= 0) + regmap_write(mux->regmap, mux->upd_ofs, + BIT(mux->upd_shift)); + } + + if (mux->lock) + spin_unlock_irqrestore(mux->lock, flags); + else + __release(mux->lock); + + return 0; +} + +const struct clk_ops mtk_mux_ops = { + .get_parent = mtk_clk_mux_get_parent, + .set_parent = mtk_clk_mux_set_parent_lock, +}; + +const struct clk_ops mtk_mux_clr_set_upd_ops = { + .get_parent = mtk_clk_mux_get_parent, + .set_parent = mtk_clk_mux_set_parent_setclr_lock, +}; + +const struct clk_ops mtk_mux_gate_ops = { + .enable = mtk_clk_mux_enable, + .disable = mtk_clk_mux_disable, + .is_enabled = mtk_clk_mux_is_enabled, + .get_parent = mtk_clk_mux_get_parent, + .set_parent = mtk_clk_mux_set_parent_lock, +}; + +const struct clk_ops mtk_mux_gate_clr_set_upd_ops = { + .enable = mtk_clk_mux_enable_setclr, + .disable = mtk_clk_mux_disable_setclr, + .is_enabled = mtk_clk_mux_is_enabled, + .get_parent = mtk_clk_mux_get_parent, + .set_parent = mtk_clk_mux_set_parent_setclr_lock, +}; + +struct clk *mtk_clk_register_mux(const struct mtk_mux *mux, + struct regmap *regmap, + spinlock_t *lock) +{ + struct mtk_clk_mux *mtk_mux; + struct clk_init_data init; + struct clk *clk; + + mtk_mux = kzalloc(sizeof(*mtk_mux), GFP_KERNEL); + if (!mtk_mux) + return ERR_PTR(-ENOMEM); + + init.name = mux->name; + init.flags = mux->flags | CLK_SET_RATE_PARENT; + init.parent_names = mux->parent_names; + init.num_parents = mux->num_parents; + init.ops = mux->ops; + + mtk_mux->regmap = regmap; + mtk_mux->name = mux->name; + mtk_mux->mux_ofs = mux->mux_ofs; + mtk_mux->mux_set_ofs = mux->set_ofs; + mtk_mux->mux_clr_ofs = mux->clr_ofs; + mtk_mux->upd_ofs = mux->upd_ofs; + mtk_mux->mux_shift = mux->mux_shift; + mtk_mux->mux_width = mux->mux_width; + mtk_mux->gate_shift = mux->gate_shift; + mtk_mux->upd_shift = mux->upd_shift; + + mtk_mux->lock = lock; + mtk_mux->hw.init = &init; + + clk = clk_register(NULL, &mtk_mux->hw); + if (IS_ERR(clk)) { + kfree(mtk_mux); + return clk; + } + + return clk; +} + +int mtk_clk_register_muxes(const struct mtk_mux *muxes, + int num, struct device_node *node, + spinlock_t *lock, + struct clk_onecell_data *clk_data) +{ + struct regmap *regmap; + struct clk *clk; + int i; + + regmap = syscon_node_to_regmap(node); + if (IS_ERR(regmap)) { + pr_err("Cannot find regmap for %pOF: %ld\n", node, + PTR_ERR(regmap)); + return PTR_ERR(regmap); + } + + for (i = 0; i < num; i++) { + const struct mtk_mux *mux = &muxes[i]; + + if (IS_ERR_OR_NULL(clk_data->clks[mux->id])) { + clk = mtk_clk_register_mux(mux, regmap, lock); + + if (IS_ERR(clk)) { + pr_err("Failed to register clk %s: %ld\n", + mux->name, PTR_ERR(clk)); + continue; + } + + clk_data->clks[mux->id] = clk; + } + } + + return 0; +} diff --git a/drivers/clk/mediatek/clk-mux.h b/drivers/clk/mediatek/clk-mux.h new file mode 100644 index 000000000000..830a6117e670 --- /dev/null +++ b/drivers/clk/mediatek/clk-mux.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2018 MediaTek Inc. + * Author: Owen Chen owen.chen@mediatek.com + */ + +#ifndef __DRV_CLK_MTK_MUX_H +#define __DRV_CLK_MTK_MUX_H + +#include <linux/clk-provider.h> + +struct mtk_clk_mux { + struct clk_hw hw; + struct regmap *regmap; + + const char *name; + + u32 mux_set_ofs; + u32 mux_clr_ofs; + u32 mux_ofs; + u32 upd_ofs; + + u8 mux_shift; + u8 mux_width; + u8 gate_shift; + s8 upd_shift; + + spinlock_t *lock; +}; + +struct mtk_mux { + int id; + const char *name; + const char * const *parent_names; + unsigned int flags; + + u32 mux_ofs; + u32 set_ofs; + u32 clr_ofs; + u32 upd_ofs; + + u8 mux_shift; + u8 mux_width; + u8 gate_shift; + s8 upd_shift; + + const struct clk_ops *ops; + + signed char num_parents; +}; + +extern const struct clk_ops mtk_mux_ops; +extern const struct clk_ops mtk_mux_clr_set_upd_ops; +extern const struct clk_ops mtk_mux_gate_ops; +extern const struct clk_ops mtk_mux_gate_clr_set_upd_ops; + +#define GATE_CLR_SET_UPD_FLAGS(_id, _name, _parents, _mux_ofs, \ + _mux_set_ofs, _mux_clr_ofs, _shift, _width, \ + _gate, _upd_ofs, _upd, _flags, _ops) { \ + .id = _id, \ + .name = _name, \ + .mux_ofs = _mux_ofs, \ + .set_ofs = _mux_set_ofs, \ + .clr_ofs = _mux_clr_ofs, \ + .upd_ofs = _upd_ofs, \ + .mux_shift = _shift, \ + .mux_width = _width, \ + .gate_shift = _gate, \ + .upd_shift = _upd, \ + .parent_names = _parents, \ + .num_parents = ARRAY_SIZE(_parents), \ + .flags = _flags, \ + .ops = &_ops, \ + } + +#define MUX_GATE_CLR_SET_UPD_FLAGS(_id, _name, _parents, _mux_ofs, \ + _mux_set_ofs, _mux_clr_ofs, _shift, _width, \ + _gate, _upd_ofs, _upd, _flags) \ + GATE_CLR_SET_UPD_FLAGS(_id, _name, _parents, _mux_ofs, \ + _mux_set_ofs, _mux_clr_ofs, _shift, _width, \ + _gate, _upd_ofs, _upd, _flags, \ + mtk_mux_gate_clr_set_upd_ops) + +#define MUX_GATE_CLR_SET_UPD(_id, _name, _parents, _mux_ofs, \ + _mux_set_ofs, _mux_clr_ofs, _shift, _width, \ + _gate, _upd_ofs, _upd) \ + MUX_GATE_CLR_SET_UPD_FLAGS(_id, _name, _parents, \ + _mux_ofs, _mux_set_ofs, _mux_clr_ofs, _shift, \ + _width, _gate, _upd_ofs, _upd, \ + CLK_SET_RATE_PARENT) + +struct clk *mtk_clk_register_mux(const struct mtk_mux *mux, + struct regmap *regmap, + spinlock_t *lock); + +int mtk_clk_register_muxes(const struct mtk_mux *muxes, + int num, struct device_node *node, + spinlock_t *lock, + struct clk_onecell_data *clk_data); + +#endif /* __DRV_CLK_MTK_MUX_H */