From 2792c37e94c80ae374ddabe24d624286566d4f3d Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Mon, 26 Mar 2018 23:09:04 +0530 Subject: [PATCH] clk: actions: Add pll clock support Add support for Actions Semi PLL clock. Signed-off-by: Manivannan Sadhasivam Signed-off-by: Stephen Boyd --- drivers/clk/actions/Makefile | 1 + drivers/clk/actions/owl-pll.c | 194 ++++++++++++++++++++++++++++++++++ drivers/clk/actions/owl-pll.h | 92 ++++++++++++++++ 3 files changed, 287 insertions(+) create mode 100644 drivers/clk/actions/owl-pll.c create mode 100644 drivers/clk/actions/owl-pll.h diff --git a/drivers/clk/actions/Makefile b/drivers/clk/actions/Makefile index 53431aef6e9c..31b68eab9309 100644 --- a/drivers/clk/actions/Makefile +++ b/drivers/clk/actions/Makefile @@ -6,3 +6,4 @@ clk-owl-y += owl-mux.o clk-owl-y += owl-divider.o clk-owl-y += owl-factor.o clk-owl-y += owl-composite.o +clk-owl-y += owl-pll.o diff --git a/drivers/clk/actions/owl-pll.c b/drivers/clk/actions/owl-pll.c new file mode 100644 index 000000000000..058e06d7099f --- /dev/null +++ b/drivers/clk/actions/owl-pll.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// OWL pll clock driver +// +// Copyright (c) 2014 Actions Semi Inc. +// Author: David Liu +// +// Copyright (c) 2018 Linaro Ltd. +// Author: Manivannan Sadhasivam + +#include +#include +#include +#include + +#include "owl-pll.h" + +static u32 owl_pll_calculate_mul(struct owl_pll_hw *pll_hw, unsigned long rate) +{ + u32 mul; + + mul = DIV_ROUND_CLOSEST(rate, pll_hw->bfreq); + if (mul < pll_hw->min_mul) + mul = pll_hw->min_mul; + else if (mul > pll_hw->max_mul) + mul = pll_hw->max_mul; + + return mul &= mul_mask(pll_hw); +} + +static unsigned long _get_table_rate(const struct clk_pll_table *table, + unsigned int val) +{ + const struct clk_pll_table *clkt; + + for (clkt = table; clkt->rate; clkt++) + if (clkt->val == val) + return clkt->rate; + + return 0; +} + +static const struct clk_pll_table *_get_pll_table( + const struct clk_pll_table *table, unsigned long rate) +{ + const struct clk_pll_table *clkt; + + for (clkt = table; clkt->rate; clkt++) { + if (clkt->rate == rate) { + table = clkt; + break; + } else if (clkt->rate < rate) + table = clkt; + } + + return table; +} + +static long owl_pll_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct owl_pll *pll = hw_to_owl_pll(hw); + struct owl_pll_hw *pll_hw = &pll->pll_hw; + const struct clk_pll_table *clkt; + u32 mul; + + if (pll_hw->table) { + clkt = _get_pll_table(pll_hw->table, rate); + return clkt->rate; + } + + /* fixed frequency */ + if (pll_hw->width == 0) + return pll_hw->bfreq; + + mul = owl_pll_calculate_mul(pll_hw, rate); + + return pll_hw->bfreq * mul; +} + +static unsigned long owl_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct owl_pll *pll = hw_to_owl_pll(hw); + struct owl_pll_hw *pll_hw = &pll->pll_hw; + const struct owl_clk_common *common = &pll->common; + u32 val; + + if (pll_hw->table) { + regmap_read(common->regmap, pll_hw->reg, &val); + + val = val >> pll_hw->shift; + val &= mul_mask(pll_hw); + + return _get_table_rate(pll_hw->table, val); + } + + /* fixed frequency */ + if (pll_hw->width == 0) + return pll_hw->bfreq; + + regmap_read(common->regmap, pll_hw->reg, &val); + + val = val >> pll_hw->shift; + val &= mul_mask(pll_hw); + + return pll_hw->bfreq * val; +} + +static int owl_pll_is_enabled(struct clk_hw *hw) +{ + struct owl_pll *pll = hw_to_owl_pll(hw); + struct owl_pll_hw *pll_hw = &pll->pll_hw; + const struct owl_clk_common *common = &pll->common; + u32 reg; + + regmap_read(common->regmap, pll_hw->reg, ®); + + return !!(reg & BIT(pll_hw->bit_idx)); +} + +static void owl_pll_set(const struct owl_clk_common *common, + const struct owl_pll_hw *pll_hw, bool enable) +{ + u32 reg; + + regmap_read(common->regmap, pll_hw->reg, ®); + + if (enable) + reg |= BIT(pll_hw->bit_idx); + else + reg &= ~BIT(pll_hw->bit_idx); + + regmap_write(common->regmap, pll_hw->reg, reg); +} + +static int owl_pll_enable(struct clk_hw *hw) +{ + struct owl_pll *pll = hw_to_owl_pll(hw); + const struct owl_clk_common *common = &pll->common; + + owl_pll_set(common, &pll->pll_hw, true); + + return 0; +} + +static void owl_pll_disable(struct clk_hw *hw) +{ + struct owl_pll *pll = hw_to_owl_pll(hw); + const struct owl_clk_common *common = &pll->common; + + owl_pll_set(common, &pll->pll_hw, false); +} + +static int owl_pll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct owl_pll *pll = hw_to_owl_pll(hw); + struct owl_pll_hw *pll_hw = &pll->pll_hw; + const struct owl_clk_common *common = &pll->common; + const struct clk_pll_table *clkt; + u32 val, reg; + + /* fixed frequency */ + if (pll_hw->width == 0) + return 0; + + if (pll_hw->table) { + clkt = _get_pll_table(pll_hw->table, rate); + val = clkt->val; + } else { + val = owl_pll_calculate_mul(pll_hw, rate); + } + + regmap_read(common->regmap, pll_hw->reg, ®); + + reg &= ~mul_mask(pll_hw); + reg |= val << pll_hw->shift; + + regmap_write(common->regmap, pll_hw->reg, reg); + + udelay(PLL_STABILITY_WAIT_US); + + return 0; +} + +const struct clk_ops owl_pll_ops = { + .enable = owl_pll_enable, + .disable = owl_pll_disable, + .is_enabled = owl_pll_is_enabled, + .round_rate = owl_pll_round_rate, + .recalc_rate = owl_pll_recalc_rate, + .set_rate = owl_pll_set_rate, +}; diff --git a/drivers/clk/actions/owl-pll.h b/drivers/clk/actions/owl-pll.h new file mode 100644 index 000000000000..0aae30abd5dc --- /dev/null +++ b/drivers/clk/actions/owl-pll.h @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// OWL pll clock driver +// +// Copyright (c) 2014 Actions Semi Inc. +// Author: David Liu +// +// Copyright (c) 2018 Linaro Ltd. +// Author: Manivannan Sadhasivam + +#ifndef _OWL_PLL_H_ +#define _OWL_PLL_H_ + +#include "owl-common.h" + +/* last entry should have rate = 0 */ +struct clk_pll_table { + unsigned int val; + unsigned long rate; +}; + +struct owl_pll_hw { + u32 reg; + u32 bfreq; + u8 bit_idx; + u8 shift; + u8 width; + u8 min_mul; + u8 max_mul; + const struct clk_pll_table *table; +}; + +struct owl_pll { + struct owl_pll_hw pll_hw; + struct owl_clk_common common; +}; + +#define OWL_PLL_HW(_reg, _bfreq, _bit_idx, _shift, \ + _width, _min_mul, _max_mul, _table) \ + { \ + .reg = _reg, \ + .bfreq = _bfreq, \ + .bit_idx = _bit_idx, \ + .shift = _shift, \ + .width = _width, \ + .min_mul = _min_mul, \ + .max_mul = _max_mul, \ + .table = _table, \ + } + +#define OWL_PLL(_struct, _name, _parent, _reg, _bfreq, _bit_idx, \ + _shift, _width, _min_mul, _max_mul, _table, _flags) \ + struct owl_pll _struct = { \ + .pll_hw = OWL_PLL_HW(_reg, _bfreq, _bit_idx, _shift, \ + _width, _min_mul, \ + _max_mul, _table), \ + .common = { \ + .regmap = NULL, \ + .hw.init = CLK_HW_INIT(_name, \ + _parent, \ + &owl_pll_ops, \ + _flags), \ + }, \ + } + +#define OWL_PLL_NO_PARENT(_struct, _name, _reg, _bfreq, _bit_idx, \ + _shift, _width, _min_mul, _max_mul, _table, _flags) \ + struct owl_pll _struct = { \ + .pll_hw = OWL_PLL_HW(_reg, _bfreq, _bit_idx, _shift, \ + _width, _min_mul, \ + _max_mul, _table), \ + .common = { \ + .regmap = NULL, \ + .hw.init = CLK_HW_INIT_NO_PARENT(_name, \ + &owl_pll_ops, \ + _flags), \ + }, \ + } + +#define mul_mask(m) ((1 << ((m)->width)) - 1) +#define PLL_STABILITY_WAIT_US (50) + +static inline struct owl_pll *hw_to_owl_pll(const struct clk_hw *hw) +{ + struct owl_clk_common *common = hw_to_owl_clk_common(hw); + + return container_of(common, struct owl_pll, common); +} + +extern const struct clk_ops owl_pll_ops; + +#endif /* _OWL_PLL_H_ */