1 /* 2 * This program is free software; you can redistribute it and/or 3 * modify it under the terms of the GNU General Public License as 4 * published by the Free Software Foundation version 2. 5 * 6 * This program is distributed "as is" WITHOUT ANY WARRANTY of any 7 * kind, whether express or implied; without even the implied warranty 8 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 9 * GNU General Public License for more details. 10 */ 11 12 #include <linux/clk-provider.h> 13 #include <linux/delay.h> 14 #include <linux/err.h> 15 #include <linux/math64.h> 16 #include <linux/of.h> 17 #include <linux/of_address.h> 18 #include <linux/clk/ti.h> 19 20 /* FAPLL Control Register PLL_CTRL */ 21 #define FAPLL_MAIN_MULT_N_SHIFT 16 22 #define FAPLL_MAIN_DIV_P_SHIFT 8 23 #define FAPLL_MAIN_LOCK BIT(7) 24 #define FAPLL_MAIN_PLLEN BIT(3) 25 #define FAPLL_MAIN_BP BIT(2) 26 #define FAPLL_MAIN_LOC_CTL BIT(0) 27 28 #define FAPLL_MAIN_MAX_MULT_N 0xffff 29 #define FAPLL_MAIN_MAX_DIV_P 0xff 30 #define FAPLL_MAIN_CLEAR_MASK \ 31 ((FAPLL_MAIN_MAX_MULT_N << FAPLL_MAIN_MULT_N_SHIFT) | \ 32 (FAPLL_MAIN_DIV_P_SHIFT << FAPLL_MAIN_DIV_P_SHIFT) | \ 33 FAPLL_MAIN_LOC_CTL) 34 35 /* FAPLL powerdown register PWD */ 36 #define FAPLL_PWD_OFFSET 4 37 38 #define MAX_FAPLL_OUTPUTS 7 39 #define FAPLL_MAX_RETRIES 1000 40 41 #define to_fapll(_hw) container_of(_hw, struct fapll_data, hw) 42 #define to_synth(_hw) container_of(_hw, struct fapll_synth, hw) 43 44 /* The bypass bit is inverted on the ddr_pll.. */ 45 #define fapll_is_ddr_pll(va) (((u32)(va) & 0xffff) == 0x0440) 46 47 /* 48 * The audio_pll_clk1 input is hard wired to the 27MHz bypass clock, 49 * and the audio_pll_clk1 synthesizer is hardwared to 32KiHz output. 50 */ 51 #define is_ddr_pll_clk1(va) (((u32)(va) & 0xffff) == 0x044c) 52 #define is_audio_pll_clk1(va) (((u32)(va) & 0xffff) == 0x04a8) 53 54 /* Synthesizer divider register */ 55 #define SYNTH_LDMDIV1 BIT(8) 56 57 /* Synthesizer frequency register */ 58 #define SYNTH_LDFREQ BIT(31) 59 60 #define SYNTH_PHASE_K 8 61 #define SYNTH_MAX_INT_DIV 0xf 62 #define SYNTH_MAX_DIV_M 0xff 63 64 struct fapll_data { 65 struct clk_hw hw; 66 void __iomem *base; 67 const char *name; 68 struct clk *clk_ref; 69 struct clk *clk_bypass; 70 struct clk_onecell_data outputs; 71 bool bypass_bit_inverted; 72 }; 73 74 struct fapll_synth { 75 struct clk_hw hw; 76 struct fapll_data *fd; 77 int index; 78 void __iomem *freq; 79 void __iomem *div; 80 const char *name; 81 struct clk *clk_pll; 82 }; 83 84 static bool ti_fapll_clock_is_bypass(struct fapll_data *fd) 85 { 86 u32 v = readl_relaxed(fd->base); 87 88 if (fd->bypass_bit_inverted) 89 return !(v & FAPLL_MAIN_BP); 90 else 91 return !!(v & FAPLL_MAIN_BP); 92 } 93 94 static void ti_fapll_set_bypass(struct fapll_data *fd) 95 { 96 u32 v = readl_relaxed(fd->base); 97 98 if (fd->bypass_bit_inverted) 99 v &= ~FAPLL_MAIN_BP; 100 else 101 v |= FAPLL_MAIN_BP; 102 writel_relaxed(v, fd->base); 103 } 104 105 static void ti_fapll_clear_bypass(struct fapll_data *fd) 106 { 107 u32 v = readl_relaxed(fd->base); 108 109 if (fd->bypass_bit_inverted) 110 v |= FAPLL_MAIN_BP; 111 else 112 v &= ~FAPLL_MAIN_BP; 113 writel_relaxed(v, fd->base); 114 } 115 116 static int ti_fapll_wait_lock(struct fapll_data *fd) 117 { 118 int retries = FAPLL_MAX_RETRIES; 119 u32 v; 120 121 while ((v = readl_relaxed(fd->base))) { 122 if (v & FAPLL_MAIN_LOCK) 123 return 0; 124 125 if (retries-- <= 0) 126 break; 127 128 udelay(1); 129 } 130 131 pr_err("%s failed to lock\n", fd->name); 132 133 return -ETIMEDOUT; 134 } 135 136 static int ti_fapll_enable(struct clk_hw *hw) 137 { 138 struct fapll_data *fd = to_fapll(hw); 139 u32 v = readl_relaxed(fd->base); 140 141 v |= FAPLL_MAIN_PLLEN; 142 writel_relaxed(v, fd->base); 143 ti_fapll_wait_lock(fd); 144 145 return 0; 146 } 147 148 static void ti_fapll_disable(struct clk_hw *hw) 149 { 150 struct fapll_data *fd = to_fapll(hw); 151 u32 v = readl_relaxed(fd->base); 152 153 v &= ~FAPLL_MAIN_PLLEN; 154 writel_relaxed(v, fd->base); 155 } 156 157 static int ti_fapll_is_enabled(struct clk_hw *hw) 158 { 159 struct fapll_data *fd = to_fapll(hw); 160 u32 v = readl_relaxed(fd->base); 161 162 return v & FAPLL_MAIN_PLLEN; 163 } 164 165 static unsigned long ti_fapll_recalc_rate(struct clk_hw *hw, 166 unsigned long parent_rate) 167 { 168 struct fapll_data *fd = to_fapll(hw); 169 u32 fapll_n, fapll_p, v; 170 long long rate; 171 172 if (ti_fapll_clock_is_bypass(fd)) 173 return parent_rate; 174 175 rate = parent_rate; 176 177 /* PLL pre-divider is P and multiplier is N */ 178 v = readl_relaxed(fd->base); 179 fapll_p = (v >> 8) & 0xff; 180 if (fapll_p) 181 do_div(rate, fapll_p); 182 fapll_n = v >> 16; 183 if (fapll_n) 184 rate *= fapll_n; 185 186 return rate; 187 } 188 189 static u8 ti_fapll_get_parent(struct clk_hw *hw) 190 { 191 struct fapll_data *fd = to_fapll(hw); 192 193 if (ti_fapll_clock_is_bypass(fd)) 194 return 1; 195 196 return 0; 197 } 198 199 static int ti_fapll_set_div_mult(unsigned long rate, 200 unsigned long parent_rate, 201 u32 *pre_div_p, u32 *mult_n) 202 { 203 /* 204 * So far no luck getting decent clock with PLL divider, 205 * PLL does not seem to lock and the signal does not look 206 * right. It seems the divider can only be used together 207 * with the multiplier? 208 */ 209 if (rate < parent_rate) { 210 pr_warn("FAPLL main divider rates unsupported\n"); 211 return -EINVAL; 212 } 213 214 *mult_n = rate / parent_rate; 215 if (*mult_n > FAPLL_MAIN_MAX_MULT_N) 216 return -EINVAL; 217 *pre_div_p = 1; 218 219 return 0; 220 } 221 222 static long ti_fapll_round_rate(struct clk_hw *hw, unsigned long rate, 223 unsigned long *parent_rate) 224 { 225 u32 pre_div_p, mult_n; 226 int error; 227 228 if (!rate) 229 return -EINVAL; 230 231 error = ti_fapll_set_div_mult(rate, *parent_rate, 232 &pre_div_p, &mult_n); 233 if (error) 234 return error; 235 236 rate = *parent_rate / pre_div_p; 237 rate *= mult_n; 238 239 return rate; 240 } 241 242 static int ti_fapll_set_rate(struct clk_hw *hw, unsigned long rate, 243 unsigned long parent_rate) 244 { 245 struct fapll_data *fd = to_fapll(hw); 246 u32 pre_div_p, mult_n, v; 247 int error; 248 249 if (!rate) 250 return -EINVAL; 251 252 error = ti_fapll_set_div_mult(rate, parent_rate, 253 &pre_div_p, &mult_n); 254 if (error) 255 return error; 256 257 ti_fapll_set_bypass(fd); 258 v = readl_relaxed(fd->base); 259 v &= ~FAPLL_MAIN_CLEAR_MASK; 260 v |= pre_div_p << FAPLL_MAIN_DIV_P_SHIFT; 261 v |= mult_n << FAPLL_MAIN_MULT_N_SHIFT; 262 writel_relaxed(v, fd->base); 263 if (ti_fapll_is_enabled(hw)) 264 ti_fapll_wait_lock(fd); 265 ti_fapll_clear_bypass(fd); 266 267 return 0; 268 } 269 270 static struct clk_ops ti_fapll_ops = { 271 .enable = ti_fapll_enable, 272 .disable = ti_fapll_disable, 273 .is_enabled = ti_fapll_is_enabled, 274 .recalc_rate = ti_fapll_recalc_rate, 275 .get_parent = ti_fapll_get_parent, 276 .round_rate = ti_fapll_round_rate, 277 .set_rate = ti_fapll_set_rate, 278 }; 279 280 static int ti_fapll_synth_enable(struct clk_hw *hw) 281 { 282 struct fapll_synth *synth = to_synth(hw); 283 u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET); 284 285 v &= ~(1 << synth->index); 286 writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET); 287 288 return 0; 289 } 290 291 static void ti_fapll_synth_disable(struct clk_hw *hw) 292 { 293 struct fapll_synth *synth = to_synth(hw); 294 u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET); 295 296 v |= 1 << synth->index; 297 writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET); 298 } 299 300 static int ti_fapll_synth_is_enabled(struct clk_hw *hw) 301 { 302 struct fapll_synth *synth = to_synth(hw); 303 u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET); 304 305 return !(v & (1 << synth->index)); 306 } 307 308 /* 309 * See dm816x TRM chapter 1.10.3 Flying Adder PLL fore more info 310 */ 311 static unsigned long ti_fapll_synth_recalc_rate(struct clk_hw *hw, 312 unsigned long parent_rate) 313 { 314 struct fapll_synth *synth = to_synth(hw); 315 u32 synth_div_m; 316 long long rate; 317 318 /* The audio_pll_clk1 is hardwired to produce 32.768KiHz clock */ 319 if (!synth->div) 320 return 32768; 321 322 /* 323 * PLL in bypass sets the synths in bypass mode too. The PLL rate 324 * can be also be set to 27MHz, so we can't use parent_rate to 325 * check for bypass mode. 326 */ 327 if (ti_fapll_clock_is_bypass(synth->fd)) 328 return parent_rate; 329 330 rate = parent_rate; 331 332 /* 333 * Synth frequency integer and fractional divider. 334 * Note that the phase output K is 8, so the result needs 335 * to be multiplied by SYNTH_PHASE_K. 336 */ 337 if (synth->freq) { 338 u32 v, synth_int_div, synth_frac_div, synth_div_freq; 339 340 v = readl_relaxed(synth->freq); 341 synth_int_div = (v >> 24) & 0xf; 342 synth_frac_div = v & 0xffffff; 343 synth_div_freq = (synth_int_div * 10000000) + synth_frac_div; 344 rate *= 10000000; 345 do_div(rate, synth_div_freq); 346 rate *= SYNTH_PHASE_K; 347 } 348 349 /* Synth post-divider M */ 350 synth_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M; 351 352 return DIV_ROUND_UP_ULL(rate, synth_div_m); 353 } 354 355 static unsigned long ti_fapll_synth_get_frac_rate(struct clk_hw *hw, 356 unsigned long parent_rate) 357 { 358 struct fapll_synth *synth = to_synth(hw); 359 unsigned long current_rate, frac_rate; 360 u32 post_div_m; 361 362 current_rate = ti_fapll_synth_recalc_rate(hw, parent_rate); 363 post_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M; 364 frac_rate = current_rate * post_div_m; 365 366 return frac_rate; 367 } 368 369 static u32 ti_fapll_synth_set_frac_rate(struct fapll_synth *synth, 370 unsigned long rate, 371 unsigned long parent_rate) 372 { 373 u32 post_div_m, synth_int_div = 0, synth_frac_div = 0, v; 374 375 post_div_m = DIV_ROUND_UP_ULL((u64)parent_rate * SYNTH_PHASE_K, rate); 376 post_div_m = post_div_m / SYNTH_MAX_INT_DIV; 377 if (post_div_m > SYNTH_MAX_DIV_M) 378 return -EINVAL; 379 if (!post_div_m) 380 post_div_m = 1; 381 382 for (; post_div_m < SYNTH_MAX_DIV_M; post_div_m++) { 383 synth_int_div = DIV_ROUND_UP_ULL((u64)parent_rate * 384 SYNTH_PHASE_K * 385 10000000, 386 rate * post_div_m); 387 synth_frac_div = synth_int_div % 10000000; 388 synth_int_div /= 10000000; 389 390 if (synth_int_div <= SYNTH_MAX_INT_DIV) 391 break; 392 } 393 394 if (synth_int_div > SYNTH_MAX_INT_DIV) 395 return -EINVAL; 396 397 v = readl_relaxed(synth->freq); 398 v &= ~0x1fffffff; 399 v |= (synth_int_div & SYNTH_MAX_INT_DIV) << 24; 400 v |= (synth_frac_div & 0xffffff); 401 v |= SYNTH_LDFREQ; 402 writel_relaxed(v, synth->freq); 403 404 return post_div_m; 405 } 406 407 static long ti_fapll_synth_round_rate(struct clk_hw *hw, unsigned long rate, 408 unsigned long *parent_rate) 409 { 410 struct fapll_synth *synth = to_synth(hw); 411 struct fapll_data *fd = synth->fd; 412 unsigned long r; 413 414 if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate) 415 return -EINVAL; 416 417 /* Only post divider m available with no fractional divider? */ 418 if (!synth->freq) { 419 unsigned long frac_rate; 420 u32 synth_post_div_m; 421 422 frac_rate = ti_fapll_synth_get_frac_rate(hw, *parent_rate); 423 synth_post_div_m = DIV_ROUND_UP(frac_rate, rate); 424 r = DIV_ROUND_UP(frac_rate, synth_post_div_m); 425 goto out; 426 } 427 428 r = *parent_rate * SYNTH_PHASE_K; 429 if (rate > r) 430 goto out; 431 432 r = DIV_ROUND_UP_ULL(r, SYNTH_MAX_INT_DIV * SYNTH_MAX_DIV_M); 433 if (rate < r) 434 goto out; 435 436 r = rate; 437 out: 438 return r; 439 } 440 441 static int ti_fapll_synth_set_rate(struct clk_hw *hw, unsigned long rate, 442 unsigned long parent_rate) 443 { 444 struct fapll_synth *synth = to_synth(hw); 445 struct fapll_data *fd = synth->fd; 446 unsigned long frac_rate, post_rate = 0; 447 u32 post_div_m = 0, v; 448 449 if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate) 450 return -EINVAL; 451 452 /* Produce the rate with just post divider M? */ 453 frac_rate = ti_fapll_synth_get_frac_rate(hw, parent_rate); 454 if (frac_rate < rate) { 455 if (!synth->freq) 456 return -EINVAL; 457 } else { 458 post_div_m = DIV_ROUND_UP(frac_rate, rate); 459 if (post_div_m && (post_div_m <= SYNTH_MAX_DIV_M)) 460 post_rate = DIV_ROUND_UP(frac_rate, post_div_m); 461 if (!synth->freq && !post_rate) 462 return -EINVAL; 463 } 464 465 /* Need to recalculate the fractional divider? */ 466 if ((post_rate != rate) && synth->freq) 467 post_div_m = ti_fapll_synth_set_frac_rate(synth, 468 rate, 469 parent_rate); 470 471 v = readl_relaxed(synth->div); 472 v &= ~SYNTH_MAX_DIV_M; 473 v |= post_div_m; 474 v |= SYNTH_LDMDIV1; 475 writel_relaxed(v, synth->div); 476 477 return 0; 478 } 479 480 static struct clk_ops ti_fapll_synt_ops = { 481 .enable = ti_fapll_synth_enable, 482 .disable = ti_fapll_synth_disable, 483 .is_enabled = ti_fapll_synth_is_enabled, 484 .recalc_rate = ti_fapll_synth_recalc_rate, 485 .round_rate = ti_fapll_synth_round_rate, 486 .set_rate = ti_fapll_synth_set_rate, 487 }; 488 489 static struct clk * __init ti_fapll_synth_setup(struct fapll_data *fd, 490 void __iomem *freq, 491 void __iomem *div, 492 int index, 493 const char *name, 494 const char *parent, 495 struct clk *pll_clk) 496 { 497 struct clk_init_data *init; 498 struct fapll_synth *synth; 499 500 init = kzalloc(sizeof(*init), GFP_KERNEL); 501 if (!init) 502 return ERR_PTR(-ENOMEM); 503 504 init->ops = &ti_fapll_synt_ops; 505 init->name = name; 506 init->parent_names = &parent; 507 init->num_parents = 1; 508 509 synth = kzalloc(sizeof(*synth), GFP_KERNEL); 510 if (!synth) 511 goto free; 512 513 synth->fd = fd; 514 synth->index = index; 515 synth->freq = freq; 516 synth->div = div; 517 synth->name = name; 518 synth->hw.init = init; 519 synth->clk_pll = pll_clk; 520 521 return clk_register(NULL, &synth->hw); 522 523 free: 524 kfree(synth); 525 kfree(init); 526 527 return ERR_PTR(-ENOMEM); 528 } 529 530 static void __init ti_fapll_setup(struct device_node *node) 531 { 532 struct fapll_data *fd; 533 struct clk_init_data *init = NULL; 534 const char *parent_name[2]; 535 struct clk *pll_clk; 536 int i; 537 538 fd = kzalloc(sizeof(*fd), GFP_KERNEL); 539 if (!fd) 540 return; 541 542 fd->outputs.clks = kzalloc(sizeof(struct clk *) * 543 MAX_FAPLL_OUTPUTS + 1, 544 GFP_KERNEL); 545 if (!fd->outputs.clks) 546 goto free; 547 548 init = kzalloc(sizeof(*init), GFP_KERNEL); 549 if (!init) 550 goto free; 551 552 init->ops = &ti_fapll_ops; 553 init->name = node->name; 554 555 init->num_parents = of_clk_get_parent_count(node); 556 if (init->num_parents != 2) { 557 pr_err("%s must have two parents\n", node->name); 558 goto free; 559 } 560 561 parent_name[0] = of_clk_get_parent_name(node, 0); 562 parent_name[1] = of_clk_get_parent_name(node, 1); 563 init->parent_names = parent_name; 564 565 fd->clk_ref = of_clk_get(node, 0); 566 if (IS_ERR(fd->clk_ref)) { 567 pr_err("%s could not get clk_ref\n", node->name); 568 goto free; 569 } 570 571 fd->clk_bypass = of_clk_get(node, 1); 572 if (IS_ERR(fd->clk_bypass)) { 573 pr_err("%s could not get clk_bypass\n", node->name); 574 goto free; 575 } 576 577 fd->base = of_iomap(node, 0); 578 if (!fd->base) { 579 pr_err("%s could not get IO base\n", node->name); 580 goto free; 581 } 582 583 if (fapll_is_ddr_pll(fd->base)) 584 fd->bypass_bit_inverted = true; 585 586 fd->name = node->name; 587 fd->hw.init = init; 588 589 /* Register the parent PLL */ 590 pll_clk = clk_register(NULL, &fd->hw); 591 if (IS_ERR(pll_clk)) 592 goto unmap; 593 594 fd->outputs.clks[0] = pll_clk; 595 fd->outputs.clk_num++; 596 597 /* 598 * Set up the child synthesizers starting at index 1 as the 599 * PLL output is at index 0. We need to check the clock-indices 600 * for numbering in case there are holes in the synth mapping, 601 * and then probe the synth register to see if it has a FREQ 602 * register available. 603 */ 604 for (i = 0; i < MAX_FAPLL_OUTPUTS; i++) { 605 const char *output_name; 606 void __iomem *freq, *div; 607 struct clk *synth_clk; 608 int output_instance; 609 u32 v; 610 611 if (of_property_read_string_index(node, "clock-output-names", 612 i, &output_name)) 613 continue; 614 615 if (of_property_read_u32_index(node, "clock-indices", i, 616 &output_instance)) 617 output_instance = i; 618 619 freq = fd->base + (output_instance * 8); 620 div = freq + 4; 621 622 /* Check for hardwired audio_pll_clk1 */ 623 if (is_audio_pll_clk1(freq)) { 624 freq = 0; 625 div = 0; 626 } else { 627 /* Does the synthesizer have a FREQ register? */ 628 v = readl_relaxed(freq); 629 if (!v) 630 freq = 0; 631 } 632 synth_clk = ti_fapll_synth_setup(fd, freq, div, output_instance, 633 output_name, node->name, 634 pll_clk); 635 if (IS_ERR(synth_clk)) 636 continue; 637 638 fd->outputs.clks[output_instance] = synth_clk; 639 fd->outputs.clk_num++; 640 641 clk_register_clkdev(synth_clk, output_name, NULL); 642 } 643 644 /* Register the child synthesizers as the FAPLL outputs */ 645 of_clk_add_provider(node, of_clk_src_onecell_get, &fd->outputs); 646 /* Add clock alias for the outputs */ 647 648 kfree(init); 649 650 return; 651 652 unmap: 653 iounmap(fd->base); 654 free: 655 if (fd->clk_bypass) 656 clk_put(fd->clk_bypass); 657 if (fd->clk_ref) 658 clk_put(fd->clk_ref); 659 kfree(fd->outputs.clks); 660 kfree(fd); 661 kfree(init); 662 } 663 664 CLK_OF_DECLARE(ti_fapll_clock, "ti,dm816-fapll-clock", ti_fapll_setup); 665