1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2016 Maxime Ripard 4 * Maxime Ripard <maxime.ripard@free-electrons.com> 5 */ 6 7 #include <linux/clk-provider.h> 8 #include <linux/io.h> 9 10 #include "ccu_frac.h" 11 #include "ccu_gate.h" 12 #include "ccu_nm.h" 13 14 struct _ccu_nm { 15 unsigned long n, min_n, max_n; 16 unsigned long m, min_m, max_m; 17 }; 18 19 static unsigned long ccu_nm_calc_rate(unsigned long parent, 20 unsigned long n, unsigned long m) 21 { 22 u64 rate = parent; 23 24 rate *= n; 25 do_div(rate, m); 26 27 return rate; 28 } 29 30 static unsigned long ccu_nm_find_best(struct ccu_common *common, unsigned long parent, 31 unsigned long rate, struct _ccu_nm *nm) 32 { 33 unsigned long best_rate = 0; 34 unsigned long best_n = 0, best_m = 0; 35 unsigned long _n, _m; 36 37 for (_n = nm->min_n; _n <= nm->max_n; _n++) { 38 for (_m = nm->min_m; _m <= nm->max_m; _m++) { 39 unsigned long tmp_rate = ccu_nm_calc_rate(parent, 40 _n, _m); 41 42 if (ccu_is_better_rate(common, rate, tmp_rate, best_rate)) { 43 best_rate = tmp_rate; 44 best_n = _n; 45 best_m = _m; 46 } 47 } 48 } 49 50 nm->n = best_n; 51 nm->m = best_m; 52 53 return best_rate; 54 } 55 56 static void ccu_nm_disable(struct clk_hw *hw) 57 { 58 struct ccu_nm *nm = hw_to_ccu_nm(hw); 59 60 return ccu_gate_helper_disable(&nm->common, nm->enable); 61 } 62 63 static int ccu_nm_enable(struct clk_hw *hw) 64 { 65 struct ccu_nm *nm = hw_to_ccu_nm(hw); 66 67 return ccu_gate_helper_enable(&nm->common, nm->enable); 68 } 69 70 static int ccu_nm_is_enabled(struct clk_hw *hw) 71 { 72 struct ccu_nm *nm = hw_to_ccu_nm(hw); 73 74 return ccu_gate_helper_is_enabled(&nm->common, nm->enable); 75 } 76 77 static unsigned long ccu_nm_recalc_rate(struct clk_hw *hw, 78 unsigned long parent_rate) 79 { 80 struct ccu_nm *nm = hw_to_ccu_nm(hw); 81 unsigned long rate; 82 unsigned long n, m; 83 u32 reg; 84 85 if (ccu_frac_helper_is_enabled(&nm->common, &nm->frac)) { 86 rate = ccu_frac_helper_read_rate(&nm->common, &nm->frac); 87 88 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 89 rate /= nm->fixed_post_div; 90 91 return rate; 92 } 93 94 reg = readl(nm->common.base + nm->common.reg); 95 96 n = reg >> nm->n.shift; 97 n &= (1 << nm->n.width) - 1; 98 n += nm->n.offset; 99 if (!n) 100 n++; 101 102 m = reg >> nm->m.shift; 103 m &= (1 << nm->m.width) - 1; 104 m += nm->m.offset; 105 if (!m) 106 m++; 107 108 if (ccu_sdm_helper_is_enabled(&nm->common, &nm->sdm)) 109 rate = ccu_sdm_helper_read_rate(&nm->common, &nm->sdm, m, n); 110 else 111 rate = ccu_nm_calc_rate(parent_rate, n, m); 112 113 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 114 rate /= nm->fixed_post_div; 115 116 return rate; 117 } 118 119 static long ccu_nm_round_rate(struct clk_hw *hw, unsigned long rate, 120 unsigned long *parent_rate) 121 { 122 struct ccu_nm *nm = hw_to_ccu_nm(hw); 123 struct _ccu_nm _nm; 124 125 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 126 rate *= nm->fixed_post_div; 127 128 if (rate < nm->min_rate) { 129 rate = nm->min_rate; 130 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 131 rate /= nm->fixed_post_div; 132 return rate; 133 } 134 135 if (nm->max_rate && rate > nm->max_rate) { 136 rate = nm->max_rate; 137 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 138 rate /= nm->fixed_post_div; 139 return rate; 140 } 141 142 if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) { 143 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 144 rate /= nm->fixed_post_div; 145 return rate; 146 } 147 148 if (ccu_sdm_helper_has_rate(&nm->common, &nm->sdm, rate)) { 149 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 150 rate /= nm->fixed_post_div; 151 return rate; 152 } 153 154 _nm.min_n = nm->n.min ?: 1; 155 _nm.max_n = nm->n.max ?: 1 << nm->n.width; 156 _nm.min_m = 1; 157 _nm.max_m = nm->m.max ?: 1 << nm->m.width; 158 159 rate = ccu_nm_find_best(&nm->common, *parent_rate, rate, &_nm); 160 161 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 162 rate /= nm->fixed_post_div; 163 164 return rate; 165 } 166 167 static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate, 168 unsigned long parent_rate) 169 { 170 struct ccu_nm *nm = hw_to_ccu_nm(hw); 171 struct _ccu_nm _nm; 172 unsigned long flags; 173 u32 reg; 174 175 /* Adjust target rate according to post-dividers */ 176 if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV) 177 rate = rate * nm->fixed_post_div; 178 179 if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) { 180 spin_lock_irqsave(nm->common.lock, flags); 181 182 /* most SoCs require M to be 0 if fractional mode is used */ 183 reg = readl(nm->common.base + nm->common.reg); 184 reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift); 185 writel(reg, nm->common.base + nm->common.reg); 186 187 spin_unlock_irqrestore(nm->common.lock, flags); 188 189 ccu_frac_helper_enable(&nm->common, &nm->frac); 190 191 return ccu_frac_helper_set_rate(&nm->common, &nm->frac, 192 rate, nm->lock); 193 } else { 194 ccu_frac_helper_disable(&nm->common, &nm->frac); 195 } 196 197 _nm.min_n = nm->n.min ?: 1; 198 _nm.max_n = nm->n.max ?: 1 << nm->n.width; 199 _nm.min_m = 1; 200 _nm.max_m = nm->m.max ?: 1 << nm->m.width; 201 202 if (ccu_sdm_helper_has_rate(&nm->common, &nm->sdm, rate)) { 203 ccu_sdm_helper_enable(&nm->common, &nm->sdm, rate); 204 205 /* Sigma delta modulation requires specific N and M factors */ 206 ccu_sdm_helper_get_factors(&nm->common, &nm->sdm, rate, 207 &_nm.m, &_nm.n); 208 } else { 209 ccu_sdm_helper_disable(&nm->common, &nm->sdm); 210 ccu_nm_find_best(&nm->common, parent_rate, rate, &_nm); 211 } 212 213 spin_lock_irqsave(nm->common.lock, flags); 214 215 reg = readl(nm->common.base + nm->common.reg); 216 reg &= ~GENMASK(nm->n.width + nm->n.shift - 1, nm->n.shift); 217 reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift); 218 219 reg |= (_nm.n - nm->n.offset) << nm->n.shift; 220 reg |= (_nm.m - nm->m.offset) << nm->m.shift; 221 writel(reg, nm->common.base + nm->common.reg); 222 223 spin_unlock_irqrestore(nm->common.lock, flags); 224 225 ccu_helper_wait_for_lock(&nm->common, nm->lock); 226 227 return 0; 228 } 229 230 const struct clk_ops ccu_nm_ops = { 231 .disable = ccu_nm_disable, 232 .enable = ccu_nm_enable, 233 .is_enabled = ccu_nm_is_enabled, 234 235 .recalc_rate = ccu_nm_recalc_rate, 236 .round_rate = ccu_nm_round_rate, 237 .set_rate = ccu_nm_set_rate, 238 }; 239 EXPORT_SYMBOL_NS_GPL(ccu_nm_ops, SUNXI_CCU); 240