1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2014 MediaTek Inc. 4 * Author: James Liao <jamesjj.liao@mediatek.com> 5 */ 6 7 #include <linux/clk-provider.h> 8 #include <linux/container_of.h> 9 #include <linux/delay.h> 10 #include <linux/err.h> 11 #include <linux/io.h> 12 #include <linux/module.h> 13 #include <linux/of_address.h> 14 #include <linux/slab.h> 15 16 #include "clk-pll.h" 17 18 #define MHZ (1000 * 1000) 19 20 #define REG_CON0 0 21 #define REG_CON1 4 22 23 #define CON0_BASE_EN BIT(0) 24 #define CON0_PWR_ON BIT(0) 25 #define CON0_ISO_EN BIT(1) 26 #define PCW_CHG_MASK BIT(31) 27 28 #define AUDPLL_TUNER_EN BIT(31) 29 30 /* default 7 bits integer, can be overridden with pcwibits. */ 31 #define INTEGER_BITS 7 32 33 int mtk_pll_is_prepared(struct clk_hw *hw) 34 { 35 struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); 36 37 return (readl(pll->en_addr) & BIT(pll->data->pll_en_bit)) != 0; 38 } 39 40 static unsigned long __mtk_pll_recalc_rate(struct mtk_clk_pll *pll, u32 fin, 41 u32 pcw, int postdiv) 42 { 43 int pcwbits = pll->data->pcwbits; 44 int pcwfbits = 0; 45 int ibits; 46 u64 vco; 47 u8 c = 0; 48 49 /* The fractional part of the PLL divider. */ 50 ibits = pll->data->pcwibits ? pll->data->pcwibits : INTEGER_BITS; 51 if (pcwbits > ibits) 52 pcwfbits = pcwbits - ibits; 53 54 vco = (u64)fin * pcw; 55 56 if (pcwfbits && (vco & GENMASK(pcwfbits - 1, 0))) 57 c = 1; 58 59 vco >>= pcwfbits; 60 61 if (c) 62 vco++; 63 64 return ((unsigned long)vco + postdiv - 1) / postdiv; 65 } 66 67 static void __mtk_pll_tuner_enable(struct mtk_clk_pll *pll) 68 { 69 u32 r; 70 71 if (pll->tuner_en_addr) { 72 r = readl(pll->tuner_en_addr) | BIT(pll->data->tuner_en_bit); 73 writel(r, pll->tuner_en_addr); 74 } else if (pll->tuner_addr) { 75 r = readl(pll->tuner_addr) | AUDPLL_TUNER_EN; 76 writel(r, pll->tuner_addr); 77 } 78 } 79 80 static void __mtk_pll_tuner_disable(struct mtk_clk_pll *pll) 81 { 82 u32 r; 83 84 if (pll->tuner_en_addr) { 85 r = readl(pll->tuner_en_addr) & ~BIT(pll->data->tuner_en_bit); 86 writel(r, pll->tuner_en_addr); 87 } else if (pll->tuner_addr) { 88 r = readl(pll->tuner_addr) & ~AUDPLL_TUNER_EN; 89 writel(r, pll->tuner_addr); 90 } 91 } 92 93 static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw, 94 int postdiv) 95 { 96 u32 chg, val; 97 98 /* disable tuner */ 99 __mtk_pll_tuner_disable(pll); 100 101 /* set postdiv */ 102 val = readl(pll->pd_addr); 103 val &= ~(POSTDIV_MASK << pll->data->pd_shift); 104 val |= (ffs(postdiv) - 1) << pll->data->pd_shift; 105 106 /* postdiv and pcw need to set at the same time if on same register */ 107 if (pll->pd_addr != pll->pcw_addr) { 108 writel(val, pll->pd_addr); 109 val = readl(pll->pcw_addr); 110 } 111 112 /* set pcw */ 113 val &= ~GENMASK(pll->data->pcw_shift + pll->data->pcwbits - 1, 114 pll->data->pcw_shift); 115 val |= pcw << pll->data->pcw_shift; 116 writel(val, pll->pcw_addr); 117 chg = readl(pll->pcw_chg_addr) | PCW_CHG_MASK; 118 writel(chg, pll->pcw_chg_addr); 119 if (pll->tuner_addr) 120 writel(val + 1, pll->tuner_addr); 121 122 /* restore tuner_en */ 123 __mtk_pll_tuner_enable(pll); 124 125 udelay(20); 126 } 127 128 /* 129 * mtk_pll_calc_values - calculate good values for a given input frequency. 130 * @pll: The pll 131 * @pcw: The pcw value (output) 132 * @postdiv: The post divider (output) 133 * @freq: The desired target frequency 134 * @fin: The input frequency 135 * 136 */ 137 void mtk_pll_calc_values(struct mtk_clk_pll *pll, u32 *pcw, u32 *postdiv, 138 u32 freq, u32 fin) 139 { 140 unsigned long fmin = pll->data->fmin ? pll->data->fmin : (1000 * MHZ); 141 const struct mtk_pll_div_table *div_table = pll->data->div_table; 142 u64 _pcw; 143 int ibits; 144 u32 val; 145 146 if (freq > pll->data->fmax) 147 freq = pll->data->fmax; 148 149 if (div_table) { 150 if (freq > div_table[0].freq) 151 freq = div_table[0].freq; 152 153 for (val = 0; div_table[val + 1].freq != 0; val++) { 154 if (freq > div_table[val + 1].freq) 155 break; 156 } 157 *postdiv = 1 << val; 158 } else { 159 for (val = 0; val < 5; val++) { 160 *postdiv = 1 << val; 161 if ((u64)freq * *postdiv >= fmin) 162 break; 163 } 164 } 165 166 /* _pcw = freq * postdiv / fin * 2^pcwfbits */ 167 ibits = pll->data->pcwibits ? pll->data->pcwibits : INTEGER_BITS; 168 _pcw = ((u64)freq << val) << (pll->data->pcwbits - ibits); 169 do_div(_pcw, fin); 170 171 *pcw = (u32)_pcw; 172 } 173 174 int mtk_pll_set_rate(struct clk_hw *hw, unsigned long rate, 175 unsigned long parent_rate) 176 { 177 struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); 178 u32 pcw = 0; 179 u32 postdiv; 180 181 mtk_pll_calc_values(pll, &pcw, &postdiv, rate, parent_rate); 182 mtk_pll_set_rate_regs(pll, pcw, postdiv); 183 184 return 0; 185 } 186 187 unsigned long mtk_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) 188 { 189 struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); 190 u32 postdiv; 191 u32 pcw; 192 193 postdiv = (readl(pll->pd_addr) >> pll->data->pd_shift) & POSTDIV_MASK; 194 postdiv = 1 << postdiv; 195 196 pcw = readl(pll->pcw_addr) >> pll->data->pcw_shift; 197 pcw &= GENMASK(pll->data->pcwbits - 1, 0); 198 199 return __mtk_pll_recalc_rate(pll, parent_rate, pcw, postdiv); 200 } 201 202 long mtk_pll_round_rate(struct clk_hw *hw, unsigned long rate, 203 unsigned long *prate) 204 { 205 struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); 206 u32 pcw = 0; 207 int postdiv; 208 209 mtk_pll_calc_values(pll, &pcw, &postdiv, rate, *prate); 210 211 return __mtk_pll_recalc_rate(pll, *prate, pcw, postdiv); 212 } 213 214 int mtk_pll_prepare(struct clk_hw *hw) 215 { 216 struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); 217 u32 r; 218 219 r = readl(pll->pwr_addr) | CON0_PWR_ON; 220 writel(r, pll->pwr_addr); 221 udelay(1); 222 223 r = readl(pll->pwr_addr) & ~CON0_ISO_EN; 224 writel(r, pll->pwr_addr); 225 udelay(1); 226 227 r = readl(pll->en_addr) | BIT(pll->data->pll_en_bit); 228 writel(r, pll->en_addr); 229 230 if (pll->data->en_mask) { 231 r = readl(pll->base_addr + REG_CON0) | pll->data->en_mask; 232 writel(r, pll->base_addr + REG_CON0); 233 } 234 235 __mtk_pll_tuner_enable(pll); 236 237 udelay(20); 238 239 if (pll->data->flags & HAVE_RST_BAR) { 240 r = readl(pll->base_addr + REG_CON0); 241 r |= pll->data->rst_bar_mask; 242 writel(r, pll->base_addr + REG_CON0); 243 } 244 245 return 0; 246 } 247 248 void mtk_pll_unprepare(struct clk_hw *hw) 249 { 250 struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); 251 u32 r; 252 253 if (pll->data->flags & HAVE_RST_BAR) { 254 r = readl(pll->base_addr + REG_CON0); 255 r &= ~pll->data->rst_bar_mask; 256 writel(r, pll->base_addr + REG_CON0); 257 } 258 259 __mtk_pll_tuner_disable(pll); 260 261 if (pll->data->en_mask) { 262 r = readl(pll->base_addr + REG_CON0) & ~pll->data->en_mask; 263 writel(r, pll->base_addr + REG_CON0); 264 } 265 266 r = readl(pll->en_addr) & ~BIT(pll->data->pll_en_bit); 267 writel(r, pll->en_addr); 268 269 r = readl(pll->pwr_addr) | CON0_ISO_EN; 270 writel(r, pll->pwr_addr); 271 272 r = readl(pll->pwr_addr) & ~CON0_PWR_ON; 273 writel(r, pll->pwr_addr); 274 } 275 276 const struct clk_ops mtk_pll_ops = { 277 .is_prepared = mtk_pll_is_prepared, 278 .prepare = mtk_pll_prepare, 279 .unprepare = mtk_pll_unprepare, 280 .recalc_rate = mtk_pll_recalc_rate, 281 .round_rate = mtk_pll_round_rate, 282 .set_rate = mtk_pll_set_rate, 283 }; 284 285 struct clk_hw *mtk_clk_register_pll_ops(struct mtk_clk_pll *pll, 286 const struct mtk_pll_data *data, 287 void __iomem *base, 288 const struct clk_ops *pll_ops) 289 { 290 struct clk_init_data init = {}; 291 int ret; 292 const char *parent_name = "clk26m"; 293 294 pll->base_addr = base + data->reg; 295 pll->pwr_addr = base + data->pwr_reg; 296 pll->pd_addr = base + data->pd_reg; 297 pll->pcw_addr = base + data->pcw_reg; 298 if (data->pcw_chg_reg) 299 pll->pcw_chg_addr = base + data->pcw_chg_reg; 300 else 301 pll->pcw_chg_addr = pll->base_addr + REG_CON1; 302 if (data->tuner_reg) 303 pll->tuner_addr = base + data->tuner_reg; 304 if (data->tuner_en_reg || data->tuner_en_bit) 305 pll->tuner_en_addr = base + data->tuner_en_reg; 306 if (data->en_reg) 307 pll->en_addr = base + data->en_reg; 308 else 309 pll->en_addr = pll->base_addr + REG_CON0; 310 pll->hw.init = &init; 311 pll->data = data; 312 313 init.name = data->name; 314 init.flags = (data->flags & PLL_AO) ? CLK_IS_CRITICAL : 0; 315 init.ops = pll_ops; 316 if (data->parent_name) 317 init.parent_names = &data->parent_name; 318 else 319 init.parent_names = &parent_name; 320 init.num_parents = 1; 321 322 ret = clk_hw_register(NULL, &pll->hw); 323 324 if (ret) { 325 kfree(pll); 326 return ERR_PTR(ret); 327 } 328 329 return &pll->hw; 330 } 331 332 struct clk_hw *mtk_clk_register_pll(const struct mtk_pll_data *data, 333 void __iomem *base) 334 { 335 struct mtk_clk_pll *pll; 336 struct clk_hw *hw; 337 338 pll = kzalloc(sizeof(*pll), GFP_KERNEL); 339 if (!pll) 340 return ERR_PTR(-ENOMEM); 341 342 hw = mtk_clk_register_pll_ops(pll, data, base, &mtk_pll_ops); 343 344 return hw; 345 } 346 347 void mtk_clk_unregister_pll(struct clk_hw *hw) 348 { 349 struct mtk_clk_pll *pll; 350 351 if (!hw) 352 return; 353 354 pll = to_mtk_clk_pll(hw); 355 356 clk_hw_unregister(hw); 357 kfree(pll); 358 } 359 360 int mtk_clk_register_plls(struct device_node *node, 361 const struct mtk_pll_data *plls, int num_plls, 362 struct clk_hw_onecell_data *clk_data) 363 { 364 void __iomem *base; 365 int i; 366 struct clk_hw *hw; 367 368 base = of_iomap(node, 0); 369 if (!base) { 370 pr_err("%s(): ioremap failed\n", __func__); 371 return -EINVAL; 372 } 373 374 for (i = 0; i < num_plls; i++) { 375 const struct mtk_pll_data *pll = &plls[i]; 376 377 if (!IS_ERR_OR_NULL(clk_data->hws[pll->id])) { 378 pr_warn("%pOF: Trying to register duplicate clock ID: %d\n", 379 node, pll->id); 380 continue; 381 } 382 383 hw = mtk_clk_register_pll(pll, base); 384 385 if (IS_ERR(hw)) { 386 pr_err("Failed to register clk %s: %pe\n", pll->name, 387 hw); 388 goto err; 389 } 390 391 clk_data->hws[pll->id] = hw; 392 } 393 394 return 0; 395 396 err: 397 while (--i >= 0) { 398 const struct mtk_pll_data *pll = &plls[i]; 399 400 mtk_clk_unregister_pll(clk_data->hws[pll->id]); 401 clk_data->hws[pll->id] = ERR_PTR(-ENOENT); 402 } 403 404 iounmap(base); 405 406 return PTR_ERR(hw); 407 } 408 EXPORT_SYMBOL_GPL(mtk_clk_register_plls); 409 410 __iomem void *mtk_clk_pll_get_base(struct clk_hw *hw, 411 const struct mtk_pll_data *data) 412 { 413 struct mtk_clk_pll *pll = to_mtk_clk_pll(hw); 414 415 return pll->base_addr - data->reg; 416 } 417 418 void mtk_clk_unregister_plls(const struct mtk_pll_data *plls, int num_plls, 419 struct clk_hw_onecell_data *clk_data) 420 { 421 __iomem void *base = NULL; 422 int i; 423 424 if (!clk_data) 425 return; 426 427 for (i = num_plls; i > 0; i--) { 428 const struct mtk_pll_data *pll = &plls[i - 1]; 429 430 if (IS_ERR_OR_NULL(clk_data->hws[pll->id])) 431 continue; 432 433 /* 434 * This is quite ugly but unfortunately the clks don't have 435 * any device tied to them, so there's no place to store the 436 * pointer to the I/O region base address. We have to fetch 437 * it from one of the registered clks. 438 */ 439 base = mtk_clk_pll_get_base(clk_data->hws[pll->id], pll); 440 441 mtk_clk_unregister_pll(clk_data->hws[pll->id]); 442 clk_data->hws[pll->id] = ERR_PTR(-ENOENT); 443 } 444 445 iounmap(base); 446 } 447 EXPORT_SYMBOL_GPL(mtk_clk_unregister_plls); 448 449 MODULE_LICENSE("GPL"); 450