1 // SPDX-License-Identifier: GPL-2.0+ 2 // 3 // OWL pll clock driver 4 // 5 // Copyright (c) 2014 Actions Semi Inc. 6 // Author: David Liu <liuwei@actions-semi.com> 7 // 8 // Copyright (c) 2018 Linaro Ltd. 9 // Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> 10 11 #include <linux/clk-provider.h> 12 #include <linux/slab.h> 13 #include <linux/io.h> 14 #include <linux/delay.h> 15 16 #include "owl-pll.h" 17 18 static u32 owl_pll_calculate_mul(struct owl_pll_hw *pll_hw, unsigned long rate) 19 { 20 u32 mul; 21 22 mul = DIV_ROUND_CLOSEST(rate, pll_hw->bfreq); 23 if (mul < pll_hw->min_mul) 24 mul = pll_hw->min_mul; 25 else if (mul > pll_hw->max_mul) 26 mul = pll_hw->max_mul; 27 28 return mul &= mul_mask(pll_hw); 29 } 30 31 static unsigned long _get_table_rate(const struct clk_pll_table *table, 32 unsigned int val) 33 { 34 const struct clk_pll_table *clkt; 35 36 for (clkt = table; clkt->rate; clkt++) 37 if (clkt->val == val) 38 return clkt->rate; 39 40 return 0; 41 } 42 43 static const struct clk_pll_table *_get_pll_table( 44 const struct clk_pll_table *table, unsigned long rate) 45 { 46 const struct clk_pll_table *clkt; 47 48 for (clkt = table; clkt->rate; clkt++) { 49 if (clkt->rate == rate) { 50 table = clkt; 51 break; 52 } else if (clkt->rate < rate) 53 table = clkt; 54 } 55 56 return table; 57 } 58 59 static long owl_pll_round_rate(struct clk_hw *hw, unsigned long rate, 60 unsigned long *parent_rate) 61 { 62 struct owl_pll *pll = hw_to_owl_pll(hw); 63 struct owl_pll_hw *pll_hw = &pll->pll_hw; 64 const struct clk_pll_table *clkt; 65 u32 mul; 66 67 if (pll_hw->table) { 68 clkt = _get_pll_table(pll_hw->table, rate); 69 return clkt->rate; 70 } 71 72 /* fixed frequency */ 73 if (pll_hw->width == 0) 74 return pll_hw->bfreq; 75 76 mul = owl_pll_calculate_mul(pll_hw, rate); 77 78 return pll_hw->bfreq * mul; 79 } 80 81 static unsigned long owl_pll_recalc_rate(struct clk_hw *hw, 82 unsigned long parent_rate) 83 { 84 struct owl_pll *pll = hw_to_owl_pll(hw); 85 struct owl_pll_hw *pll_hw = &pll->pll_hw; 86 const struct owl_clk_common *common = &pll->common; 87 u32 val; 88 89 if (pll_hw->table) { 90 regmap_read(common->regmap, pll_hw->reg, &val); 91 92 val = val >> pll_hw->shift; 93 val &= mul_mask(pll_hw); 94 95 return _get_table_rate(pll_hw->table, val); 96 } 97 98 /* fixed frequency */ 99 if (pll_hw->width == 0) 100 return pll_hw->bfreq; 101 102 regmap_read(common->regmap, pll_hw->reg, &val); 103 104 val = val >> pll_hw->shift; 105 val &= mul_mask(pll_hw); 106 107 return pll_hw->bfreq * val; 108 } 109 110 static int owl_pll_is_enabled(struct clk_hw *hw) 111 { 112 struct owl_pll *pll = hw_to_owl_pll(hw); 113 struct owl_pll_hw *pll_hw = &pll->pll_hw; 114 const struct owl_clk_common *common = &pll->common; 115 u32 reg; 116 117 regmap_read(common->regmap, pll_hw->reg, ®); 118 119 return !!(reg & BIT(pll_hw->bit_idx)); 120 } 121 122 static void owl_pll_set(const struct owl_clk_common *common, 123 const struct owl_pll_hw *pll_hw, bool enable) 124 { 125 u32 reg; 126 127 regmap_read(common->regmap, pll_hw->reg, ®); 128 129 if (enable) 130 reg |= BIT(pll_hw->bit_idx); 131 else 132 reg &= ~BIT(pll_hw->bit_idx); 133 134 regmap_write(common->regmap, pll_hw->reg, reg); 135 } 136 137 static int owl_pll_enable(struct clk_hw *hw) 138 { 139 struct owl_pll *pll = hw_to_owl_pll(hw); 140 const struct owl_clk_common *common = &pll->common; 141 142 owl_pll_set(common, &pll->pll_hw, true); 143 144 return 0; 145 } 146 147 static void owl_pll_disable(struct clk_hw *hw) 148 { 149 struct owl_pll *pll = hw_to_owl_pll(hw); 150 const struct owl_clk_common *common = &pll->common; 151 152 owl_pll_set(common, &pll->pll_hw, false); 153 } 154 155 static int owl_pll_set_rate(struct clk_hw *hw, unsigned long rate, 156 unsigned long parent_rate) 157 { 158 struct owl_pll *pll = hw_to_owl_pll(hw); 159 struct owl_pll_hw *pll_hw = &pll->pll_hw; 160 const struct owl_clk_common *common = &pll->common; 161 const struct clk_pll_table *clkt; 162 u32 val, reg; 163 164 /* fixed frequency */ 165 if (pll_hw->width == 0) 166 return 0; 167 168 if (pll_hw->table) { 169 clkt = _get_pll_table(pll_hw->table, rate); 170 val = clkt->val; 171 } else { 172 val = owl_pll_calculate_mul(pll_hw, rate); 173 } 174 175 regmap_read(common->regmap, pll_hw->reg, ®); 176 177 reg &= ~mul_mask(pll_hw); 178 reg |= val << pll_hw->shift; 179 180 regmap_write(common->regmap, pll_hw->reg, reg); 181 182 udelay(pll_hw->delay); 183 184 return 0; 185 } 186 187 const struct clk_ops owl_pll_ops = { 188 .enable = owl_pll_enable, 189 .disable = owl_pll_disable, 190 .is_enabled = owl_pll_is_enabled, 191 .round_rate = owl_pll_round_rate, 192 .recalc_rate = owl_pll_recalc_rate, 193 .set_rate = owl_pll_set_rate, 194 }; 195