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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 | // SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com> */ #include <linux/clk-provider.h> #include <linux/clkdev.h> #include <linux/clk/at91_pmc.h> #include <linux/of.h> #include <linux/mfd/syscon.h> #include <linux/regmap.h> #include <soc/at91/atmel-sfr.h> #include "pmc.h" /* * The purpose of this clock is to generate a 480 MHz signal. A different * rate can't be configured. */ #define UTMI_RATE 480000000 struct clk_utmi { struct clk_hw hw; struct regmap *regmap_pmc; struct regmap *regmap_sfr; struct at91_clk_pms pms; }; #define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw) static inline bool clk_utmi_ready(struct regmap *regmap) { unsigned int status; regmap_read(regmap, AT91_PMC_SR, &status); return status & AT91_PMC_LOCKU; } static int clk_utmi_prepare(struct clk_hw *hw) { struct clk_hw *hw_parent; struct clk_utmi *utmi = to_clk_utmi(hw); unsigned int uckr = AT91_PMC_UPLLEN | AT91_PMC_UPLLCOUNT | AT91_PMC_BIASEN; unsigned int utmi_ref_clk_freq; unsigned long parent_rate; /* * If mainck rate is different from 12 MHz, we have to configure the * FREQ field of the SFR_UTMICKTRIM register to generate properly * the utmi clock. */ hw_parent = clk_hw_get_parent(hw); parent_rate = clk_hw_get_rate(hw_parent); switch (parent_rate) { case 12000000: utmi_ref_clk_freq = 0; break; case 16000000: utmi_ref_clk_freq = 1; break; case 24000000: utmi_ref_clk_freq = 2; break; /* * Not supported on SAMA5D2 but it's not an issue since MAINCK * maximum value is 24 MHz. */ case 48000000: utmi_ref_clk_freq = 3; break; default: pr_err("UTMICK: unsupported mainck rate\n"); return -EINVAL; } if (utmi->regmap_sfr) { regmap_update_bits(utmi->regmap_sfr, AT91_SFR_UTMICKTRIM, AT91_UTMICKTRIM_FREQ, utmi_ref_clk_freq); } else if (utmi_ref_clk_freq) { pr_err("UTMICK: sfr node required\n"); return -EINVAL; } regmap_update_bits(utmi->regmap_pmc, AT91_CKGR_UCKR, uckr, uckr); while (!clk_utmi_ready(utmi->regmap_pmc)) cpu_relax(); return 0; } static int clk_utmi_is_prepared(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); return clk_utmi_ready(utmi->regmap_pmc); } static void clk_utmi_unprepare(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); regmap_update_bits(utmi->regmap_pmc, AT91_CKGR_UCKR, AT91_PMC_UPLLEN, 0); } static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { /* UTMI clk rate is fixed. */ return UTMI_RATE; } static int clk_utmi_save_context(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); utmi->pms.status = clk_utmi_is_prepared(hw); return 0; } static void clk_utmi_restore_context(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); if (utmi->pms.status) clk_utmi_prepare(hw); } static const struct clk_ops utmi_ops = { .prepare = clk_utmi_prepare, .unprepare = clk_utmi_unprepare, .is_prepared = clk_utmi_is_prepared, .recalc_rate = clk_utmi_recalc_rate, .save_context = clk_utmi_save_context, .restore_context = clk_utmi_restore_context, }; static struct clk_hw * __init at91_clk_register_utmi_internal(struct regmap *regmap_pmc, struct regmap *regmap_sfr, const char *name, const char *parent_name, const struct clk_ops *ops, unsigned long flags) { struct clk_utmi *utmi; struct clk_hw *hw; struct clk_init_data init; int ret; utmi = kzalloc(sizeof(*utmi), GFP_KERNEL); if (!utmi) return ERR_PTR(-ENOMEM); init.name = name; init.ops = ops; init.parent_names = parent_name ? &parent_name : NULL; init.num_parents = parent_name ? 1 : 0; init.flags = flags; utmi->hw.init = &init; utmi->regmap_pmc = regmap_pmc; utmi->regmap_sfr = regmap_sfr; hw = &utmi->hw; ret = clk_hw_register(NULL, &utmi->hw); if (ret) { kfree(utmi); hw = ERR_PTR(ret); } return hw; } struct clk_hw * __init at91_clk_register_utmi(struct regmap *regmap_pmc, struct regmap *regmap_sfr, const char *name, const char *parent_name) { return at91_clk_register_utmi_internal(regmap_pmc, regmap_sfr, name, parent_name, &utmi_ops, CLK_SET_RATE_GATE); } static int clk_utmi_sama7g5_prepare(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); struct clk_hw *hw_parent; unsigned long parent_rate; unsigned int val; hw_parent = clk_hw_get_parent(hw); parent_rate = clk_hw_get_rate(hw_parent); switch (parent_rate) { case 16000000: val = 0; break; case 20000000: val = 2; break; case 24000000: val = 3; break; case 32000000: val = 5; break; default: pr_err("UTMICK: unsupported main_xtal rate\n"); return -EINVAL; } regmap_write(utmi->regmap_pmc, AT91_PMC_XTALF, val); return 0; } static int clk_utmi_sama7g5_is_prepared(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); struct clk_hw *hw_parent; unsigned long parent_rate; unsigned int val; hw_parent = clk_hw_get_parent(hw); parent_rate = clk_hw_get_rate(hw_parent); regmap_read(utmi->regmap_pmc, AT91_PMC_XTALF, &val); switch (val & 0x7) { case 0: if (parent_rate == 16000000) return 1; break; case 2: if (parent_rate == 20000000) return 1; break; case 3: if (parent_rate == 24000000) return 1; break; case 5: if (parent_rate == 32000000) return 1; break; default: break; } return 0; } static int clk_utmi_sama7g5_save_context(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); utmi->pms.status = clk_utmi_sama7g5_is_prepared(hw); return 0; } static void clk_utmi_sama7g5_restore_context(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); if (utmi->pms.status) clk_utmi_sama7g5_prepare(hw); } static const struct clk_ops sama7g5_utmi_ops = { .prepare = clk_utmi_sama7g5_prepare, .is_prepared = clk_utmi_sama7g5_is_prepared, .recalc_rate = clk_utmi_recalc_rate, .save_context = clk_utmi_sama7g5_save_context, .restore_context = clk_utmi_sama7g5_restore_context, }; struct clk_hw * __init at91_clk_sama7g5_register_utmi(struct regmap *regmap_pmc, const char *name, const char *parent_name) { return at91_clk_register_utmi_internal(regmap_pmc, NULL, name, parent_name, &sama7g5_utmi_ops, 0); } |