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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (C) 2016 Socionext Inc.4 * Author: Masahiro Yamada <yamada.masahiro@socionext.com>5 */6 7#include <linux/clk-provider.h>8#include <linux/device.h>9#include <linux/regmap.h>10 11#include "clk-uniphier.h"12 13#define UNIPHIER_CLK_CPUGEAR_STAT 0 /* status */14#define UNIPHIER_CLK_CPUGEAR_SET 4 /* set */15#define UNIPHIER_CLK_CPUGEAR_UPD 8 /* update */16#define UNIPHIER_CLK_CPUGEAR_UPD_BIT BIT(0)17 18struct uniphier_clk_cpugear {19 struct clk_hw hw;20 struct regmap *regmap;21 unsigned int regbase;22 unsigned int mask;23};24 25#define to_uniphier_clk_cpugear(_hw) \26 container_of(_hw, struct uniphier_clk_cpugear, hw)27 28static int uniphier_clk_cpugear_set_parent(struct clk_hw *hw, u8 index)29{30 struct uniphier_clk_cpugear *gear = to_uniphier_clk_cpugear(hw);31 int ret;32 unsigned int val;33 34 ret = regmap_write_bits(gear->regmap,35 gear->regbase + UNIPHIER_CLK_CPUGEAR_SET,36 gear->mask, index);37 if (ret)38 return ret;39 40 ret = regmap_write_bits(gear->regmap,41 gear->regbase + UNIPHIER_CLK_CPUGEAR_UPD,42 UNIPHIER_CLK_CPUGEAR_UPD_BIT,43 UNIPHIER_CLK_CPUGEAR_UPD_BIT);44 if (ret)45 return ret;46 47 return regmap_read_poll_timeout(gear->regmap,48 gear->regbase + UNIPHIER_CLK_CPUGEAR_UPD,49 val, !(val & UNIPHIER_CLK_CPUGEAR_UPD_BIT),50 0, 1);51}52 53static u8 uniphier_clk_cpugear_get_parent(struct clk_hw *hw)54{55 struct uniphier_clk_cpugear *gear = to_uniphier_clk_cpugear(hw);56 int num_parents = clk_hw_get_num_parents(hw);57 int ret;58 unsigned int val;59 60 ret = regmap_read(gear->regmap,61 gear->regbase + UNIPHIER_CLK_CPUGEAR_STAT, &val);62 if (ret)63 return ret;64 65 val &= gear->mask;66 67 return val < num_parents ? val : -EINVAL;68}69 70static const struct clk_ops uniphier_clk_cpugear_ops = {71 .determine_rate = __clk_mux_determine_rate,72 .set_parent = uniphier_clk_cpugear_set_parent,73 .get_parent = uniphier_clk_cpugear_get_parent,74};75 76struct clk_hw *uniphier_clk_register_cpugear(struct device *dev,77 struct regmap *regmap,78 const char *name,79 const struct uniphier_clk_cpugear_data *data)80{81 struct uniphier_clk_cpugear *gear;82 struct clk_init_data init;83 int ret;84 85 gear = devm_kzalloc(dev, sizeof(*gear), GFP_KERNEL);86 if (!gear)87 return ERR_PTR(-ENOMEM);88 89 init.name = name;90 init.ops = &uniphier_clk_cpugear_ops;91 init.flags = CLK_SET_RATE_PARENT;92 init.parent_names = data->parent_names;93 init.num_parents = data->num_parents;94 95 gear->regmap = regmap;96 gear->regbase = data->regbase;97 gear->mask = data->mask;98 gear->hw.init = &init;99 100 ret = devm_clk_hw_register(dev, &gear->hw);101 if (ret)102 return ERR_PTR(ret);103 104 return &gear->hw;105}106