1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright 2017-2018 NXP. 4 */ 5 6 #define pr_fmt(fmt) "pll14xx: " fmt 7 8 #include <linux/bitfield.h> 9 #include <linux/bits.h> 10 #include <linux/clk-provider.h> 11 #include <linux/err.h> 12 #include <linux/export.h> 13 #include <linux/io.h> 14 #include <linux/iopoll.h> 15 #include <linux/slab.h> 16 #include <linux/jiffies.h> 17 18 #include "clk.h" 19 20 #define GNRL_CTL 0x0 21 #define DIV_CTL0 0x4 22 #define DIV_CTL1 0x8 23 #define LOCK_STATUS BIT(31) 24 #define LOCK_SEL_MASK BIT(29) 25 #define CLKE_MASK BIT(11) 26 #define RST_MASK BIT(9) 27 #define BYPASS_MASK BIT(4) 28 #define MDIV_MASK GENMASK(21, 12) 29 #define PDIV_MASK GENMASK(9, 4) 30 #define SDIV_MASK GENMASK(2, 0) 31 #define KDIV_MASK GENMASK(15, 0) 32 #define KDIV_MIN SHRT_MIN 33 #define KDIV_MAX SHRT_MAX 34 35 #define LOCK_TIMEOUT_US 10000 36 37 struct clk_pll14xx { 38 struct clk_hw hw; 39 void __iomem *base; 40 enum imx_pll14xx_type type; 41 const struct imx_pll14xx_rate_table *rate_table; 42 int rate_count; 43 }; 44 45 #define to_clk_pll14xx(_hw) container_of(_hw, struct clk_pll14xx, hw) 46 47 static const struct imx_pll14xx_rate_table imx_pll1416x_tbl[] = { 48 PLL_1416X_RATE(1800000000U, 225, 3, 0), 49 PLL_1416X_RATE(1600000000U, 200, 3, 0), 50 PLL_1416X_RATE(1500000000U, 375, 3, 1), 51 PLL_1416X_RATE(1400000000U, 350, 3, 1), 52 PLL_1416X_RATE(1200000000U, 300, 3, 1), 53 PLL_1416X_RATE(1000000000U, 250, 3, 1), 54 PLL_1416X_RATE(800000000U, 200, 3, 1), 55 PLL_1416X_RATE(750000000U, 250, 2, 2), 56 PLL_1416X_RATE(700000000U, 350, 3, 2), 57 PLL_1416X_RATE(640000000U, 320, 3, 2), 58 PLL_1416X_RATE(600000000U, 300, 3, 2), 59 PLL_1416X_RATE(320000000U, 160, 3, 2), 60 }; 61 62 static const struct imx_pll14xx_rate_table imx_pll1443x_tbl[] = { 63 PLL_1443X_RATE(1039500000U, 173, 2, 1, 16384), 64 PLL_1443X_RATE(650000000U, 325, 3, 2, 0), 65 PLL_1443X_RATE(594000000U, 198, 2, 2, 0), 66 PLL_1443X_RATE(519750000U, 173, 2, 2, 16384), 67 }; 68 69 struct imx_pll14xx_clk imx_1443x_pll = { 70 .type = PLL_1443X, 71 .rate_table = imx_pll1443x_tbl, 72 .rate_count = ARRAY_SIZE(imx_pll1443x_tbl), 73 }; 74 EXPORT_SYMBOL_GPL(imx_1443x_pll); 75 76 struct imx_pll14xx_clk imx_1443x_dram_pll = { 77 .type = PLL_1443X, 78 .rate_table = imx_pll1443x_tbl, 79 .rate_count = ARRAY_SIZE(imx_pll1443x_tbl), 80 .flags = CLK_GET_RATE_NOCACHE, 81 }; 82 EXPORT_SYMBOL_GPL(imx_1443x_dram_pll); 83 84 struct imx_pll14xx_clk imx_1416x_pll = { 85 .type = PLL_1416X, 86 .rate_table = imx_pll1416x_tbl, 87 .rate_count = ARRAY_SIZE(imx_pll1416x_tbl), 88 }; 89 EXPORT_SYMBOL_GPL(imx_1416x_pll); 90 91 static const struct imx_pll14xx_rate_table *imx_get_pll_settings( 92 struct clk_pll14xx *pll, unsigned long rate) 93 { 94 const struct imx_pll14xx_rate_table *rate_table = pll->rate_table; 95 int i; 96 97 for (i = 0; i < pll->rate_count; i++) 98 if (rate == rate_table[i].rate) 99 return &rate_table[i]; 100 101 return NULL; 102 } 103 104 static long pll14xx_calc_rate(struct clk_pll14xx *pll, int mdiv, int pdiv, 105 int sdiv, int kdiv, unsigned long prate) 106 { 107 u64 fvco = prate; 108 109 /* fvco = (m * 65536 + k) * Fin / (p * 65536) */ 110 fvco *= (mdiv * 65536 + kdiv); 111 pdiv *= 65536; 112 113 do_div(fvco, pdiv << sdiv); 114 115 return fvco; 116 } 117 118 static long pll1443x_calc_kdiv(int mdiv, int pdiv, int sdiv, 119 unsigned long rate, unsigned long prate) 120 { 121 long kdiv; 122 123 /* calc kdiv = round(rate * pdiv * 65536 * 2^sdiv / prate) - (mdiv * 65536) */ 124 kdiv = ((rate * ((pdiv * 65536) << sdiv) + prate / 2) / prate) - (mdiv * 65536); 125 126 return clamp_t(short, kdiv, KDIV_MIN, KDIV_MAX); 127 } 128 129 static void imx_pll14xx_calc_settings(struct clk_pll14xx *pll, unsigned long rate, 130 unsigned long prate, struct imx_pll14xx_rate_table *t) 131 { 132 u32 pll_div_ctl0, pll_div_ctl1; 133 int mdiv, pdiv, sdiv, kdiv; 134 long fvco, rate_min, rate_max, dist, best = LONG_MAX; 135 const struct imx_pll14xx_rate_table *tt; 136 137 /* 138 * Fractional PLL constrains: 139 * 140 * a) 1 <= p <= 63 141 * b) 64 <= m <= 1023 142 * c) 0 <= s <= 6 143 * d) -32768 <= k <= 32767 144 * 145 * fvco = (m * 65536 + k) * prate / (p * 65536) 146 */ 147 148 /* First try if we can get the desired rate from one of the static entries */ 149 tt = imx_get_pll_settings(pll, rate); 150 if (tt) { 151 pr_debug("%s: in=%ld, want=%ld, Using PLL setting from table\n", 152 clk_hw_get_name(&pll->hw), prate, rate); 153 t->rate = tt->rate; 154 t->mdiv = tt->mdiv; 155 t->pdiv = tt->pdiv; 156 t->sdiv = tt->sdiv; 157 t->kdiv = tt->kdiv; 158 return; 159 } 160 161 pll_div_ctl0 = readl_relaxed(pll->base + DIV_CTL0); 162 mdiv = FIELD_GET(MDIV_MASK, pll_div_ctl0); 163 pdiv = FIELD_GET(PDIV_MASK, pll_div_ctl0); 164 sdiv = FIELD_GET(SDIV_MASK, pll_div_ctl0); 165 pll_div_ctl1 = readl_relaxed(pll->base + DIV_CTL1); 166 167 /* Then see if we can get the desired rate by only adjusting kdiv (glitch free) */ 168 rate_min = pll14xx_calc_rate(pll, mdiv, pdiv, sdiv, KDIV_MIN, prate); 169 rate_max = pll14xx_calc_rate(pll, mdiv, pdiv, sdiv, KDIV_MAX, prate); 170 171 if (rate >= rate_min && rate <= rate_max) { 172 kdiv = pll1443x_calc_kdiv(mdiv, pdiv, sdiv, rate, prate); 173 pr_debug("%s: in=%ld, want=%ld Only adjust kdiv %ld -> %d\n", 174 clk_hw_get_name(&pll->hw), prate, rate, 175 FIELD_GET(KDIV_MASK, pll_div_ctl1), kdiv); 176 fvco = pll14xx_calc_rate(pll, mdiv, pdiv, sdiv, kdiv, prate); 177 t->rate = (unsigned int)fvco; 178 t->mdiv = mdiv; 179 t->pdiv = pdiv; 180 t->sdiv = sdiv; 181 t->kdiv = kdiv; 182 return; 183 } 184 185 /* Finally calculate best values */ 186 for (pdiv = 1; pdiv <= 63; pdiv++) { 187 for (sdiv = 0; sdiv <= 6; sdiv++) { 188 /* calc mdiv = round(rate * pdiv * 2^sdiv) / prate) */ 189 mdiv = DIV_ROUND_CLOSEST(rate * (pdiv << sdiv), prate); 190 mdiv = clamp(mdiv, 64, 1023); 191 192 kdiv = pll1443x_calc_kdiv(mdiv, pdiv, sdiv, rate, prate); 193 fvco = pll14xx_calc_rate(pll, mdiv, pdiv, sdiv, kdiv, prate); 194 195 /* best match */ 196 dist = abs((long)rate - (long)fvco); 197 if (dist < best) { 198 best = dist; 199 t->rate = (unsigned int)fvco; 200 t->mdiv = mdiv; 201 t->pdiv = pdiv; 202 t->sdiv = sdiv; 203 t->kdiv = kdiv; 204 205 if (!dist) 206 goto found; 207 } 208 } 209 } 210 found: 211 pr_debug("%s: in=%ld, want=%ld got=%d (pdiv=%d sdiv=%d mdiv=%d kdiv=%d)\n", 212 clk_hw_get_name(&pll->hw), prate, rate, t->rate, t->pdiv, t->sdiv, 213 t->mdiv, t->kdiv); 214 } 215 216 static long clk_pll1416x_round_rate(struct clk_hw *hw, unsigned long rate, 217 unsigned long *prate) 218 { 219 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 220 const struct imx_pll14xx_rate_table *rate_table = pll->rate_table; 221 int i; 222 223 /* Assuming rate_table is in descending order */ 224 for (i = 0; i < pll->rate_count; i++) 225 if (rate >= rate_table[i].rate) 226 return rate_table[i].rate; 227 228 /* return minimum supported value */ 229 return rate_table[pll->rate_count - 1].rate; 230 } 231 232 static long clk_pll1443x_round_rate(struct clk_hw *hw, unsigned long rate, 233 unsigned long *prate) 234 { 235 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 236 struct imx_pll14xx_rate_table t; 237 238 imx_pll14xx_calc_settings(pll, rate, *prate, &t); 239 240 return t.rate; 241 } 242 243 static unsigned long clk_pll14xx_recalc_rate(struct clk_hw *hw, 244 unsigned long parent_rate) 245 { 246 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 247 u32 mdiv, pdiv, sdiv, kdiv, pll_div_ctl0, pll_div_ctl1; 248 249 pll_div_ctl0 = readl_relaxed(pll->base + DIV_CTL0); 250 mdiv = FIELD_GET(MDIV_MASK, pll_div_ctl0); 251 pdiv = FIELD_GET(PDIV_MASK, pll_div_ctl0); 252 sdiv = FIELD_GET(SDIV_MASK, pll_div_ctl0); 253 254 if (pll->type == PLL_1443X) { 255 pll_div_ctl1 = readl_relaxed(pll->base + DIV_CTL1); 256 kdiv = (s16)FIELD_GET(KDIV_MASK, pll_div_ctl1); 257 } else { 258 kdiv = 0; 259 } 260 261 return pll14xx_calc_rate(pll, mdiv, pdiv, sdiv, kdiv, parent_rate); 262 } 263 264 static inline bool clk_pll14xx_mp_change(const struct imx_pll14xx_rate_table *rate, 265 u32 pll_div) 266 { 267 u32 old_mdiv, old_pdiv; 268 269 old_mdiv = FIELD_GET(MDIV_MASK, pll_div); 270 old_pdiv = FIELD_GET(PDIV_MASK, pll_div); 271 272 return rate->mdiv != old_mdiv || rate->pdiv != old_pdiv; 273 } 274 275 static int clk_pll14xx_wait_lock(struct clk_pll14xx *pll) 276 { 277 u32 val; 278 279 return readl_poll_timeout(pll->base + GNRL_CTL, val, val & LOCK_STATUS, 0, 280 LOCK_TIMEOUT_US); 281 } 282 283 static int clk_pll1416x_set_rate(struct clk_hw *hw, unsigned long drate, 284 unsigned long prate) 285 { 286 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 287 const struct imx_pll14xx_rate_table *rate; 288 u32 tmp, div_val; 289 int ret; 290 291 rate = imx_get_pll_settings(pll, drate); 292 if (!rate) { 293 pr_err("Invalid rate %lu for pll clk %s\n", drate, 294 clk_hw_get_name(hw)); 295 return -EINVAL; 296 } 297 298 tmp = readl_relaxed(pll->base + DIV_CTL0); 299 300 if (!clk_pll14xx_mp_change(rate, tmp)) { 301 tmp &= ~SDIV_MASK; 302 tmp |= FIELD_PREP(SDIV_MASK, rate->sdiv); 303 writel_relaxed(tmp, pll->base + DIV_CTL0); 304 305 return 0; 306 } 307 308 /* Bypass clock and set lock to pll output lock */ 309 tmp = readl_relaxed(pll->base + GNRL_CTL); 310 tmp |= LOCK_SEL_MASK; 311 writel_relaxed(tmp, pll->base + GNRL_CTL); 312 313 /* Enable RST */ 314 tmp &= ~RST_MASK; 315 writel_relaxed(tmp, pll->base + GNRL_CTL); 316 317 /* Enable BYPASS */ 318 tmp |= BYPASS_MASK; 319 writel(tmp, pll->base + GNRL_CTL); 320 321 div_val = FIELD_PREP(MDIV_MASK, rate->mdiv) | FIELD_PREP(PDIV_MASK, rate->pdiv) | 322 FIELD_PREP(SDIV_MASK, rate->sdiv); 323 writel_relaxed(div_val, pll->base + DIV_CTL0); 324 325 /* 326 * According to SPEC, t3 - t2 need to be greater than 327 * 1us and 1/FREF, respectively. 328 * FREF is FIN / Prediv, the prediv is [1, 63], so choose 329 * 3us. 330 */ 331 udelay(3); 332 333 /* Disable RST */ 334 tmp |= RST_MASK; 335 writel_relaxed(tmp, pll->base + GNRL_CTL); 336 337 /* Wait Lock */ 338 ret = clk_pll14xx_wait_lock(pll); 339 if (ret) 340 return ret; 341 342 /* Bypass */ 343 tmp &= ~BYPASS_MASK; 344 writel_relaxed(tmp, pll->base + GNRL_CTL); 345 346 return 0; 347 } 348 349 static int clk_pll1443x_set_rate(struct clk_hw *hw, unsigned long drate, 350 unsigned long prate) 351 { 352 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 353 struct imx_pll14xx_rate_table rate; 354 u32 gnrl_ctl, div_ctl0; 355 int ret; 356 357 imx_pll14xx_calc_settings(pll, drate, prate, &rate); 358 359 div_ctl0 = readl_relaxed(pll->base + DIV_CTL0); 360 361 if (!clk_pll14xx_mp_change(&rate, div_ctl0)) { 362 /* only sdiv and/or kdiv changed - no need to RESET PLL */ 363 div_ctl0 &= ~SDIV_MASK; 364 div_ctl0 |= FIELD_PREP(SDIV_MASK, rate.sdiv); 365 writel_relaxed(div_ctl0, pll->base + DIV_CTL0); 366 367 writel_relaxed(FIELD_PREP(KDIV_MASK, rate.kdiv), 368 pll->base + DIV_CTL1); 369 370 return 0; 371 } 372 373 /* Enable RST */ 374 gnrl_ctl = readl_relaxed(pll->base + GNRL_CTL); 375 gnrl_ctl &= ~RST_MASK; 376 writel_relaxed(gnrl_ctl, pll->base + GNRL_CTL); 377 378 /* Enable BYPASS */ 379 gnrl_ctl |= BYPASS_MASK; 380 writel_relaxed(gnrl_ctl, pll->base + GNRL_CTL); 381 382 div_ctl0 = FIELD_PREP(MDIV_MASK, rate.mdiv) | 383 FIELD_PREP(PDIV_MASK, rate.pdiv) | 384 FIELD_PREP(SDIV_MASK, rate.sdiv); 385 writel_relaxed(div_ctl0, pll->base + DIV_CTL0); 386 387 writel_relaxed(FIELD_PREP(KDIV_MASK, rate.kdiv), pll->base + DIV_CTL1); 388 389 /* 390 * According to SPEC, t3 - t2 need to be greater than 391 * 1us and 1/FREF, respectively. 392 * FREF is FIN / Prediv, the prediv is [1, 63], so choose 393 * 3us. 394 */ 395 udelay(3); 396 397 /* Disable RST */ 398 gnrl_ctl |= RST_MASK; 399 writel_relaxed(gnrl_ctl, pll->base + GNRL_CTL); 400 401 /* Wait Lock*/ 402 ret = clk_pll14xx_wait_lock(pll); 403 if (ret) 404 return ret; 405 406 /* Bypass */ 407 gnrl_ctl &= ~BYPASS_MASK; 408 writel_relaxed(gnrl_ctl, pll->base + GNRL_CTL); 409 410 return 0; 411 } 412 413 static int clk_pll14xx_prepare(struct clk_hw *hw) 414 { 415 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 416 u32 val; 417 int ret; 418 419 /* 420 * RESETB = 1 from 0, PLL starts its normal 421 * operation after lock time 422 */ 423 val = readl_relaxed(pll->base + GNRL_CTL); 424 if (val & RST_MASK) 425 return 0; 426 val |= BYPASS_MASK; 427 writel_relaxed(val, pll->base + GNRL_CTL); 428 val |= RST_MASK; 429 writel_relaxed(val, pll->base + GNRL_CTL); 430 431 ret = clk_pll14xx_wait_lock(pll); 432 if (ret) 433 return ret; 434 435 val &= ~BYPASS_MASK; 436 writel_relaxed(val, pll->base + GNRL_CTL); 437 438 return 0; 439 } 440 441 static int clk_pll14xx_is_prepared(struct clk_hw *hw) 442 { 443 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 444 u32 val; 445 446 val = readl_relaxed(pll->base + GNRL_CTL); 447 448 return (val & RST_MASK) ? 1 : 0; 449 } 450 451 static void clk_pll14xx_unprepare(struct clk_hw *hw) 452 { 453 struct clk_pll14xx *pll = to_clk_pll14xx(hw); 454 u32 val; 455 456 /* 457 * Set RST to 0, power down mode is enabled and 458 * every digital block is reset 459 */ 460 val = readl_relaxed(pll->base + GNRL_CTL); 461 val &= ~RST_MASK; 462 writel_relaxed(val, pll->base + GNRL_CTL); 463 } 464 465 static const struct clk_ops clk_pll1416x_ops = { 466 .prepare = clk_pll14xx_prepare, 467 .unprepare = clk_pll14xx_unprepare, 468 .is_prepared = clk_pll14xx_is_prepared, 469 .recalc_rate = clk_pll14xx_recalc_rate, 470 .round_rate = clk_pll1416x_round_rate, 471 .set_rate = clk_pll1416x_set_rate, 472 }; 473 474 static const struct clk_ops clk_pll1416x_min_ops = { 475 .recalc_rate = clk_pll14xx_recalc_rate, 476 }; 477 478 static const struct clk_ops clk_pll1443x_ops = { 479 .prepare = clk_pll14xx_prepare, 480 .unprepare = clk_pll14xx_unprepare, 481 .is_prepared = clk_pll14xx_is_prepared, 482 .recalc_rate = clk_pll14xx_recalc_rate, 483 .round_rate = clk_pll1443x_round_rate, 484 .set_rate = clk_pll1443x_set_rate, 485 }; 486 487 struct clk_hw *imx_dev_clk_hw_pll14xx(struct device *dev, const char *name, 488 const char *parent_name, void __iomem *base, 489 const struct imx_pll14xx_clk *pll_clk) 490 { 491 struct clk_pll14xx *pll; 492 struct clk_hw *hw; 493 struct clk_init_data init; 494 int ret; 495 u32 val; 496 497 pll = kzalloc(sizeof(*pll), GFP_KERNEL); 498 if (!pll) 499 return ERR_PTR(-ENOMEM); 500 501 init.name = name; 502 init.flags = pll_clk->flags; 503 init.parent_names = &parent_name; 504 init.num_parents = 1; 505 506 switch (pll_clk->type) { 507 case PLL_1416X: 508 if (!pll_clk->rate_table) 509 init.ops = &clk_pll1416x_min_ops; 510 else 511 init.ops = &clk_pll1416x_ops; 512 break; 513 case PLL_1443X: 514 init.ops = &clk_pll1443x_ops; 515 break; 516 default: 517 pr_err("Unknown pll type for pll clk %s\n", name); 518 kfree(pll); 519 return ERR_PTR(-EINVAL); 520 } 521 522 pll->base = base; 523 pll->hw.init = &init; 524 pll->type = pll_clk->type; 525 pll->rate_table = pll_clk->rate_table; 526 pll->rate_count = pll_clk->rate_count; 527 528 val = readl_relaxed(pll->base + GNRL_CTL); 529 val &= ~BYPASS_MASK; 530 writel_relaxed(val, pll->base + GNRL_CTL); 531 532 hw = &pll->hw; 533 534 ret = clk_hw_register(dev, hw); 535 if (ret) { 536 pr_err("failed to register pll %s %d\n", name, ret); 537 kfree(pll); 538 return ERR_PTR(ret); 539 } 540 541 return hw; 542 } 543 EXPORT_SYMBOL_GPL(imx_dev_clk_hw_pll14xx); 544