1 /* 2 * TI clock support 3 * 4 * Copyright (C) 2013 Texas Instruments, Inc. 5 * 6 * Tero Kristo <t-kristo@ti.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 * This program is distributed "as is" WITHOUT ANY WARRANTY of any 13 * kind, whether express or implied; without even the implied warranty 14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 */ 17 18 #include <linux/clk.h> 19 #include <linux/clk-provider.h> 20 #include <linux/clkdev.h> 21 #include <linux/clk/ti.h> 22 #include <linux/io.h> 23 #include <linux/of.h> 24 #include <linux/of_address.h> 25 #include <linux/list.h> 26 #include <linux/regmap.h> 27 #include <linux/memblock.h> 28 #include <linux/device.h> 29 30 #include "clock.h" 31 32 #undef pr_fmt 33 #define pr_fmt(fmt) "%s: " fmt, __func__ 34 35 static LIST_HEAD(clk_hw_omap_clocks); 36 struct ti_clk_ll_ops *ti_clk_ll_ops; 37 static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS]; 38 39 struct ti_clk_features ti_clk_features; 40 41 struct clk_iomap { 42 struct regmap *regmap; 43 void __iomem *mem; 44 }; 45 46 static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS]; 47 48 static void clk_memmap_writel(u32 val, const struct clk_omap_reg *reg) 49 { 50 struct clk_iomap *io = clk_memmaps[reg->index]; 51 52 if (reg->ptr) 53 writel_relaxed(val, reg->ptr); 54 else if (io->regmap) 55 regmap_write(io->regmap, reg->offset, val); 56 else 57 writel_relaxed(val, io->mem + reg->offset); 58 } 59 60 static void _clk_rmw(u32 val, u32 mask, void __iomem *ptr) 61 { 62 u32 v; 63 64 v = readl_relaxed(ptr); 65 v &= ~mask; 66 v |= val; 67 writel_relaxed(v, ptr); 68 } 69 70 static void clk_memmap_rmw(u32 val, u32 mask, const struct clk_omap_reg *reg) 71 { 72 struct clk_iomap *io = clk_memmaps[reg->index]; 73 74 if (reg->ptr) { 75 _clk_rmw(val, mask, reg->ptr); 76 } else if (io->regmap) { 77 regmap_update_bits(io->regmap, reg->offset, mask, val); 78 } else { 79 _clk_rmw(val, mask, io->mem + reg->offset); 80 } 81 } 82 83 static u32 clk_memmap_readl(const struct clk_omap_reg *reg) 84 { 85 u32 val; 86 struct clk_iomap *io = clk_memmaps[reg->index]; 87 88 if (reg->ptr) 89 val = readl_relaxed(reg->ptr); 90 else if (io->regmap) 91 regmap_read(io->regmap, reg->offset, &val); 92 else 93 val = readl_relaxed(io->mem + reg->offset); 94 95 return val; 96 } 97 98 /** 99 * ti_clk_setup_ll_ops - setup low level clock operations 100 * @ops: low level clock ops descriptor 101 * 102 * Sets up low level clock operations for TI clock driver. This is used 103 * to provide various callbacks for the clock driver towards platform 104 * specific code. Returns 0 on success, -EBUSY if ll_ops have been 105 * registered already. 106 */ 107 int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops) 108 { 109 if (ti_clk_ll_ops) { 110 pr_err("Attempt to register ll_ops multiple times.\n"); 111 return -EBUSY; 112 } 113 114 ti_clk_ll_ops = ops; 115 ops->clk_readl = clk_memmap_readl; 116 ops->clk_writel = clk_memmap_writel; 117 ops->clk_rmw = clk_memmap_rmw; 118 119 return 0; 120 } 121 122 /* 123 * Eventually we could standardize to using '_' for clk-*.c files to follow the 124 * TRM naming and leave out the tmp name here. 125 */ 126 static struct device_node *ti_find_clock_provider(struct device_node *from, 127 const char *name) 128 { 129 struct device_node *np; 130 bool found = false; 131 const char *n; 132 char *tmp; 133 134 tmp = kstrdup(name, GFP_KERNEL); 135 if (!tmp) 136 return NULL; 137 strreplace(tmp, '-', '_'); 138 139 /* Node named "clock" with "clock-output-names" */ 140 for_each_of_allnodes_from(from, np) { 141 if (of_property_read_string_index(np, "clock-output-names", 142 0, &n)) 143 continue; 144 145 if (!strncmp(n, tmp, strlen(tmp))) { 146 found = true; 147 break; 148 } 149 } 150 of_node_put(from); 151 kfree(tmp); 152 153 if (found) 154 return np; 155 156 /* Fall back to using old node name base provider name */ 157 return of_find_node_by_name(from, name); 158 } 159 160 /** 161 * ti_dt_clocks_register - register DT alias clocks during boot 162 * @oclks: list of clocks to register 163 * 164 * Register alias or non-standard DT clock entries during boot. By 165 * default, DT clocks are found based on their clock-output-names 166 * property, or the clock node name for legacy cases. If any 167 * additional con-id / dev-id -> clock mapping is required, use this 168 * function to list these. 169 */ 170 void __init ti_dt_clocks_register(struct ti_dt_clk oclks[]) 171 { 172 struct ti_dt_clk *c; 173 struct device_node *node, *parent, *child; 174 struct clk *clk; 175 struct of_phandle_args clkspec; 176 char buf[64]; 177 char *ptr; 178 char *tags[2]; 179 int i; 180 int num_args; 181 int ret; 182 static bool clkctrl_nodes_missing; 183 static bool has_clkctrl_data; 184 static bool compat_mode; 185 186 compat_mode = ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT; 187 188 for (c = oclks; c->node_name != NULL; c++) { 189 strcpy(buf, c->node_name); 190 ptr = buf; 191 for (i = 0; i < 2; i++) 192 tags[i] = NULL; 193 num_args = 0; 194 while (*ptr) { 195 if (*ptr == ':') { 196 if (num_args >= 2) { 197 pr_warn("Bad number of tags on %s\n", 198 c->node_name); 199 return; 200 } 201 tags[num_args++] = ptr + 1; 202 *ptr = 0; 203 } 204 ptr++; 205 } 206 207 if (num_args && clkctrl_nodes_missing) 208 continue; 209 210 node = ti_find_clock_provider(NULL, buf); 211 if (num_args && compat_mode) { 212 parent = node; 213 child = of_get_child_by_name(parent, "clock"); 214 if (!child) 215 child = of_get_child_by_name(parent, "clk"); 216 if (child) { 217 of_node_put(parent); 218 node = child; 219 } 220 } 221 222 clkspec.np = node; 223 clkspec.args_count = num_args; 224 for (i = 0; i < num_args; i++) { 225 ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i); 226 if (ret) { 227 pr_warn("Bad tag in %s at %d: %s\n", 228 c->node_name, i, tags[i]); 229 of_node_put(node); 230 return; 231 } 232 } 233 clk = of_clk_get_from_provider(&clkspec); 234 of_node_put(node); 235 if (!IS_ERR(clk)) { 236 c->lk.clk = clk; 237 clkdev_add(&c->lk); 238 } else { 239 if (num_args && !has_clkctrl_data) { 240 struct device_node *np; 241 242 np = of_find_compatible_node(NULL, NULL, 243 "ti,clkctrl"); 244 if (np) { 245 has_clkctrl_data = true; 246 of_node_put(np); 247 } else { 248 clkctrl_nodes_missing = true; 249 250 pr_warn("missing clkctrl nodes, please update your dts.\n"); 251 continue; 252 } 253 } 254 255 pr_warn("failed to lookup clock node %s, ret=%ld\n", 256 c->node_name, PTR_ERR(clk)); 257 } 258 } 259 } 260 261 struct clk_init_item { 262 struct device_node *node; 263 void *user; 264 ti_of_clk_init_cb_t func; 265 struct list_head link; 266 }; 267 268 static LIST_HEAD(retry_list); 269 270 /** 271 * ti_clk_retry_init - retries a failed clock init at later phase 272 * @node: device not for the clock 273 * @user: user data pointer 274 * @func: init function to be called for the clock 275 * 276 * Adds a failed clock init to the retry list. The retry list is parsed 277 * once all the other clocks have been initialized. 278 */ 279 int __init ti_clk_retry_init(struct device_node *node, void *user, 280 ti_of_clk_init_cb_t func) 281 { 282 struct clk_init_item *retry; 283 284 pr_debug("%pOFn: adding to retry list...\n", node); 285 retry = kzalloc(sizeof(*retry), GFP_KERNEL); 286 if (!retry) 287 return -ENOMEM; 288 289 retry->node = node; 290 retry->func = func; 291 retry->user = user; 292 list_add(&retry->link, &retry_list); 293 294 return 0; 295 } 296 297 /** 298 * ti_clk_get_reg_addr - get register address for a clock register 299 * @node: device node for the clock 300 * @index: register index from the clock node 301 * @reg: pointer to target register struct 302 * 303 * Builds clock register address from device tree information, and returns 304 * the data via the provided output pointer @reg. Returns 0 on success, 305 * negative error value on failure. 306 */ 307 int ti_clk_get_reg_addr(struct device_node *node, int index, 308 struct clk_omap_reg *reg) 309 { 310 u32 val; 311 int i; 312 313 for (i = 0; i < CLK_MAX_MEMMAPS; i++) { 314 if (clocks_node_ptr[i] == node->parent) 315 break; 316 if (clocks_node_ptr[i] == node->parent->parent) 317 break; 318 } 319 320 if (i == CLK_MAX_MEMMAPS) { 321 pr_err("clk-provider not found for %pOFn!\n", node); 322 return -ENOENT; 323 } 324 325 reg->index = i; 326 327 if (of_property_read_u32_index(node, "reg", index, &val)) { 328 if (of_property_read_u32_index(node->parent, "reg", 329 index, &val)) { 330 pr_err("%pOFn or parent must have reg[%d]!\n", 331 node, index); 332 return -EINVAL; 333 } 334 } 335 336 reg->offset = val; 337 reg->ptr = NULL; 338 339 return 0; 340 } 341 342 void ti_clk_latch(struct clk_omap_reg *reg, s8 shift) 343 { 344 u32 latch; 345 346 if (shift < 0) 347 return; 348 349 latch = 1 << shift; 350 351 ti_clk_ll_ops->clk_rmw(latch, latch, reg); 352 ti_clk_ll_ops->clk_rmw(0, latch, reg); 353 ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */ 354 } 355 356 /** 357 * omap2_clk_provider_init - init master clock provider 358 * @parent: master node 359 * @index: internal index for clk_reg_ops 360 * @syscon: syscon regmap pointer for accessing clock registers 361 * @mem: iomem pointer for the clock provider memory area, only used if 362 * syscon is not provided 363 * 364 * Initializes a master clock IP block. This basically sets up the 365 * mapping from clocks node to the memory map index. All the clocks 366 * are then initialized through the common of_clk_init call, and the 367 * clocks will access their memory maps based on the node layout. 368 * Returns 0 in success. 369 */ 370 int __init omap2_clk_provider_init(struct device_node *parent, int index, 371 struct regmap *syscon, void __iomem *mem) 372 { 373 struct device_node *clocks; 374 struct clk_iomap *io; 375 376 /* get clocks for this parent */ 377 clocks = of_get_child_by_name(parent, "clocks"); 378 if (!clocks) { 379 pr_err("%pOFn missing 'clocks' child node.\n", parent); 380 return -EINVAL; 381 } 382 383 /* add clocks node info */ 384 clocks_node_ptr[index] = clocks; 385 386 io = kzalloc(sizeof(*io), GFP_KERNEL); 387 if (!io) 388 return -ENOMEM; 389 390 io->regmap = syscon; 391 io->mem = mem; 392 393 clk_memmaps[index] = io; 394 395 return 0; 396 } 397 398 /** 399 * omap2_clk_legacy_provider_init - initialize a legacy clock provider 400 * @index: index for the clock provider 401 * @mem: iomem pointer for the clock provider memory area 402 * 403 * Initializes a legacy clock provider memory mapping. 404 */ 405 void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem) 406 { 407 struct clk_iomap *io; 408 409 io = memblock_alloc(sizeof(*io), SMP_CACHE_BYTES); 410 if (!io) 411 panic("%s: Failed to allocate %zu bytes\n", __func__, 412 sizeof(*io)); 413 414 io->mem = mem; 415 416 clk_memmaps[index] = io; 417 } 418 419 /** 420 * ti_dt_clk_init_retry_clks - init clocks from the retry list 421 * 422 * Initializes any clocks that have failed to initialize before, 423 * reasons being missing parent node(s) during earlier init. This 424 * typically happens only for DPLLs which need to have both of their 425 * parent clocks ready during init. 426 */ 427 void ti_dt_clk_init_retry_clks(void) 428 { 429 struct clk_init_item *retry; 430 struct clk_init_item *tmp; 431 int retries = 5; 432 433 while (!list_empty(&retry_list) && retries) { 434 list_for_each_entry_safe(retry, tmp, &retry_list, link) { 435 pr_debug("retry-init: %pOFn\n", retry->node); 436 retry->func(retry->user, retry->node); 437 list_del(&retry->link); 438 kfree(retry); 439 } 440 retries--; 441 } 442 } 443 444 static const struct of_device_id simple_clk_match_table[] __initconst = { 445 { .compatible = "fixed-clock" }, 446 { .compatible = "fixed-factor-clock" }, 447 { } 448 }; 449 450 /** 451 * ti_dt_clk_name - init clock name from first output name or node name 452 * @np: device node 453 * 454 * Use the first clock-output-name for the clock name if found. Fall back 455 * to legacy naming based on node name. 456 */ 457 const char *ti_dt_clk_name(struct device_node *np) 458 { 459 const char *name; 460 461 if (!of_property_read_string_index(np, "clock-output-names", 0, 462 &name)) 463 return name; 464 465 return np->name; 466 } 467 468 /** 469 * ti_clk_add_aliases - setup clock aliases 470 * 471 * Sets up any missing clock aliases. No return value. 472 */ 473 void __init ti_clk_add_aliases(void) 474 { 475 struct device_node *np; 476 struct clk *clk; 477 478 for_each_matching_node(np, simple_clk_match_table) { 479 struct of_phandle_args clkspec; 480 481 clkspec.np = np; 482 clk = of_clk_get_from_provider(&clkspec); 483 484 ti_clk_add_alias(NULL, clk, ti_dt_clk_name(np)); 485 } 486 } 487 488 /** 489 * ti_clk_setup_features - setup clock features flags 490 * @features: features definition to use 491 * 492 * Initializes the clock driver features flags based on platform 493 * provided data. No return value. 494 */ 495 void __init ti_clk_setup_features(struct ti_clk_features *features) 496 { 497 memcpy(&ti_clk_features, features, sizeof(*features)); 498 } 499 500 /** 501 * ti_clk_get_features - get clock driver features flags 502 * 503 * Get TI clock driver features description. Returns a pointer 504 * to the current feature setup. 505 */ 506 const struct ti_clk_features *ti_clk_get_features(void) 507 { 508 return &ti_clk_features; 509 } 510 511 /** 512 * omap2_clk_enable_init_clocks - prepare & enable a list of clocks 513 * @clk_names: ptr to an array of strings of clock names to enable 514 * @num_clocks: number of clock names in @clk_names 515 * 516 * Prepare and enable a list of clocks, named by @clk_names. No 517 * return value. XXX Deprecated; only needed until these clocks are 518 * properly claimed and enabled by the drivers or core code that uses 519 * them. XXX What code disables & calls clk_put on these clocks? 520 */ 521 void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks) 522 { 523 struct clk *init_clk; 524 int i; 525 526 for (i = 0; i < num_clocks; i++) { 527 init_clk = clk_get(NULL, clk_names[i]); 528 if (WARN(IS_ERR(init_clk), "could not find init clock %s\n", 529 clk_names[i])) 530 continue; 531 clk_prepare_enable(init_clk); 532 } 533 } 534 535 /** 536 * ti_clk_add_alias - add a clock alias for a TI clock 537 * @dev: device alias for this clock 538 * @clk: clock handle to create alias for 539 * @con: connection ID for this clock 540 * 541 * Creates a clock alias for a TI clock. Allocates the clock lookup entry 542 * and assigns the data to it. Returns 0 if successful, negative error 543 * value otherwise. 544 */ 545 int ti_clk_add_alias(struct device *dev, struct clk *clk, const char *con) 546 { 547 struct clk_lookup *cl; 548 549 if (!clk) 550 return 0; 551 552 if (IS_ERR(clk)) 553 return PTR_ERR(clk); 554 555 cl = kzalloc(sizeof(*cl), GFP_KERNEL); 556 if (!cl) 557 return -ENOMEM; 558 559 if (dev) 560 cl->dev_id = dev_name(dev); 561 cl->con_id = con; 562 cl->clk = clk; 563 564 clkdev_add(cl); 565 566 return 0; 567 } 568 569 /** 570 * ti_clk_register - register a TI clock to the common clock framework 571 * @dev: device for this clock 572 * @hw: hardware clock handle 573 * @con: connection ID for this clock 574 * 575 * Registers a TI clock to the common clock framework, and adds a clock 576 * alias for it. Returns a handle to the registered clock if successful, 577 * ERR_PTR value in failure. 578 */ 579 struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw, 580 const char *con) 581 { 582 struct clk *clk; 583 int ret; 584 585 clk = clk_register(dev, hw); 586 if (IS_ERR(clk)) 587 return clk; 588 589 ret = ti_clk_add_alias(dev, clk, con); 590 if (ret) { 591 clk_unregister(clk); 592 return ERR_PTR(ret); 593 } 594 595 return clk; 596 } 597 598 /** 599 * ti_clk_register_omap_hw - register a clk_hw_omap to the clock framework 600 * @dev: device for this clock 601 * @hw: hardware clock handle 602 * @con: connection ID for this clock 603 * 604 * Registers a clk_hw_omap clock to the clock framewor, adds a clock alias 605 * for it, and adds the list to the available clk_hw_omap type clocks. 606 * Returns a handle to the registered clock if successful, ERR_PTR value 607 * in failure. 608 */ 609 struct clk *ti_clk_register_omap_hw(struct device *dev, struct clk_hw *hw, 610 const char *con) 611 { 612 struct clk *clk; 613 struct clk_hw_omap *oclk; 614 615 clk = ti_clk_register(dev, hw, con); 616 if (IS_ERR(clk)) 617 return clk; 618 619 oclk = to_clk_hw_omap(hw); 620 621 list_add(&oclk->node, &clk_hw_omap_clocks); 622 623 return clk; 624 } 625 626 /** 627 * omap2_clk_for_each - call function for each registered clk_hw_omap 628 * @fn: pointer to a callback function 629 * 630 * Call @fn for each registered clk_hw_omap, passing @hw to each 631 * function. @fn must return 0 for success or any other value for 632 * failure. If @fn returns non-zero, the iteration across clocks 633 * will stop and the non-zero return value will be passed to the 634 * caller of omap2_clk_for_each(). 635 */ 636 int omap2_clk_for_each(int (*fn)(struct clk_hw_omap *hw)) 637 { 638 int ret; 639 struct clk_hw_omap *hw; 640 641 list_for_each_entry(hw, &clk_hw_omap_clocks, node) { 642 ret = (*fn)(hw); 643 if (ret) 644 break; 645 } 646 647 return ret; 648 } 649 650 /** 651 * omap2_clk_is_hw_omap - check if the provided clk_hw is OMAP clock 652 * @hw: clk_hw to check if it is an omap clock or not 653 * 654 * Checks if the provided clk_hw is OMAP clock or not. Returns true if 655 * it is, false otherwise. 656 */ 657 bool omap2_clk_is_hw_omap(struct clk_hw *hw) 658 { 659 struct clk_hw_omap *oclk; 660 661 list_for_each_entry(oclk, &clk_hw_omap_clocks, node) { 662 if (&oclk->hw == hw) 663 return true; 664 } 665 666 return false; 667 } 668