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 * ti_dt_clocks_register - register DT alias clocks during boot 124 * @oclks: list of clocks to register 125 * 126 * Register alias or non-standard DT clock entries during boot. By 127 * default, DT clocks are found based on their node name. If any 128 * additional con-id / dev-id -> clock mapping is required, use this 129 * function to list these. 130 */ 131 void __init ti_dt_clocks_register(struct ti_dt_clk oclks[]) 132 { 133 struct ti_dt_clk *c; 134 struct device_node *node, *parent; 135 struct clk *clk; 136 struct of_phandle_args clkspec; 137 char buf[64]; 138 char *ptr; 139 char *tags[2]; 140 int i; 141 int num_args; 142 int ret; 143 static bool clkctrl_nodes_missing; 144 static bool has_clkctrl_data; 145 static bool compat_mode; 146 147 compat_mode = ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT; 148 149 for (c = oclks; c->node_name != NULL; c++) { 150 strcpy(buf, c->node_name); 151 ptr = buf; 152 for (i = 0; i < 2; i++) 153 tags[i] = NULL; 154 num_args = 0; 155 while (*ptr) { 156 if (*ptr == ':') { 157 if (num_args >= 2) { 158 pr_warn("Bad number of tags on %s\n", 159 c->node_name); 160 return; 161 } 162 tags[num_args++] = ptr + 1; 163 *ptr = 0; 164 } 165 ptr++; 166 } 167 168 if (num_args && clkctrl_nodes_missing) 169 continue; 170 171 node = of_find_node_by_name(NULL, buf); 172 if (num_args && compat_mode) { 173 parent = node; 174 node = of_get_child_by_name(parent, "clock"); 175 if (!node) 176 node = of_get_child_by_name(parent, "clk"); 177 of_node_put(parent); 178 } 179 180 clkspec.np = node; 181 clkspec.args_count = num_args; 182 for (i = 0; i < num_args; i++) { 183 ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i); 184 if (ret) { 185 pr_warn("Bad tag in %s at %d: %s\n", 186 c->node_name, i, tags[i]); 187 of_node_put(node); 188 return; 189 } 190 } 191 clk = of_clk_get_from_provider(&clkspec); 192 of_node_put(node); 193 if (!IS_ERR(clk)) { 194 c->lk.clk = clk; 195 clkdev_add(&c->lk); 196 } else { 197 if (num_args && !has_clkctrl_data) { 198 struct device_node *np; 199 200 np = of_find_compatible_node(NULL, NULL, 201 "ti,clkctrl"); 202 if (np) { 203 has_clkctrl_data = true; 204 of_node_put(np); 205 } else { 206 clkctrl_nodes_missing = true; 207 208 pr_warn("missing clkctrl nodes, please update your dts.\n"); 209 continue; 210 } 211 } 212 213 pr_warn("failed to lookup clock node %s, ret=%ld\n", 214 c->node_name, PTR_ERR(clk)); 215 } 216 } 217 } 218 219 struct clk_init_item { 220 struct device_node *node; 221 void *user; 222 ti_of_clk_init_cb_t func; 223 struct list_head link; 224 }; 225 226 static LIST_HEAD(retry_list); 227 228 /** 229 * ti_clk_retry_init - retries a failed clock init at later phase 230 * @node: device not for the clock 231 * @user: user data pointer 232 * @func: init function to be called for the clock 233 * 234 * Adds a failed clock init to the retry list. The retry list is parsed 235 * once all the other clocks have been initialized. 236 */ 237 int __init ti_clk_retry_init(struct device_node *node, void *user, 238 ti_of_clk_init_cb_t func) 239 { 240 struct clk_init_item *retry; 241 242 pr_debug("%pOFn: adding to retry list...\n", node); 243 retry = kzalloc(sizeof(*retry), GFP_KERNEL); 244 if (!retry) 245 return -ENOMEM; 246 247 retry->node = node; 248 retry->func = func; 249 retry->user = user; 250 list_add(&retry->link, &retry_list); 251 252 return 0; 253 } 254 255 /** 256 * ti_clk_get_reg_addr - get register address for a clock register 257 * @node: device node for the clock 258 * @index: register index from the clock node 259 * @reg: pointer to target register struct 260 * 261 * Builds clock register address from device tree information, and returns 262 * the data via the provided output pointer @reg. Returns 0 on success, 263 * negative error value on failure. 264 */ 265 int ti_clk_get_reg_addr(struct device_node *node, int index, 266 struct clk_omap_reg *reg) 267 { 268 u32 val; 269 int i; 270 271 for (i = 0; i < CLK_MAX_MEMMAPS; i++) { 272 if (clocks_node_ptr[i] == node->parent) 273 break; 274 } 275 276 if (i == CLK_MAX_MEMMAPS) { 277 pr_err("clk-provider not found for %pOFn!\n", node); 278 return -ENOENT; 279 } 280 281 reg->index = i; 282 283 if (of_property_read_u32_index(node, "reg", index, &val)) { 284 pr_err("%pOFn must have reg[%d]!\n", node, index); 285 return -EINVAL; 286 } 287 288 reg->offset = val; 289 reg->ptr = NULL; 290 291 return 0; 292 } 293 294 void ti_clk_latch(struct clk_omap_reg *reg, s8 shift) 295 { 296 u32 latch; 297 298 if (shift < 0) 299 return; 300 301 latch = 1 << shift; 302 303 ti_clk_ll_ops->clk_rmw(latch, latch, reg); 304 ti_clk_ll_ops->clk_rmw(0, latch, reg); 305 ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */ 306 } 307 308 /** 309 * omap2_clk_provider_init - init master clock provider 310 * @parent: master node 311 * @index: internal index for clk_reg_ops 312 * @syscon: syscon regmap pointer for accessing clock registers 313 * @mem: iomem pointer for the clock provider memory area, only used if 314 * syscon is not provided 315 * 316 * Initializes a master clock IP block. This basically sets up the 317 * mapping from clocks node to the memory map index. All the clocks 318 * are then initialized through the common of_clk_init call, and the 319 * clocks will access their memory maps based on the node layout. 320 * Returns 0 in success. 321 */ 322 int __init omap2_clk_provider_init(struct device_node *parent, int index, 323 struct regmap *syscon, void __iomem *mem) 324 { 325 struct device_node *clocks; 326 struct clk_iomap *io; 327 328 /* get clocks for this parent */ 329 clocks = of_get_child_by_name(parent, "clocks"); 330 if (!clocks) { 331 pr_err("%pOFn missing 'clocks' child node.\n", parent); 332 return -EINVAL; 333 } 334 335 /* add clocks node info */ 336 clocks_node_ptr[index] = clocks; 337 338 io = kzalloc(sizeof(*io), GFP_KERNEL); 339 if (!io) 340 return -ENOMEM; 341 342 io->regmap = syscon; 343 io->mem = mem; 344 345 clk_memmaps[index] = io; 346 347 return 0; 348 } 349 350 /** 351 * omap2_clk_legacy_provider_init - initialize a legacy clock provider 352 * @index: index for the clock provider 353 * @mem: iomem pointer for the clock provider memory area 354 * 355 * Initializes a legacy clock provider memory mapping. 356 */ 357 void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem) 358 { 359 struct clk_iomap *io; 360 361 io = memblock_alloc(sizeof(*io), SMP_CACHE_BYTES); 362 if (!io) 363 panic("%s: Failed to allocate %zu bytes\n", __func__, 364 sizeof(*io)); 365 366 io->mem = mem; 367 368 clk_memmaps[index] = io; 369 } 370 371 /** 372 * ti_dt_clk_init_retry_clks - init clocks from the retry list 373 * 374 * Initializes any clocks that have failed to initialize before, 375 * reasons being missing parent node(s) during earlier init. This 376 * typically happens only for DPLLs which need to have both of their 377 * parent clocks ready during init. 378 */ 379 void ti_dt_clk_init_retry_clks(void) 380 { 381 struct clk_init_item *retry; 382 struct clk_init_item *tmp; 383 int retries = 5; 384 385 while (!list_empty(&retry_list) && retries) { 386 list_for_each_entry_safe(retry, tmp, &retry_list, link) { 387 pr_debug("retry-init: %pOFn\n", retry->node); 388 retry->func(retry->user, retry->node); 389 list_del(&retry->link); 390 kfree(retry); 391 } 392 retries--; 393 } 394 } 395 396 static const struct of_device_id simple_clk_match_table[] __initconst = { 397 { .compatible = "fixed-clock" }, 398 { .compatible = "fixed-factor-clock" }, 399 { } 400 }; 401 402 /** 403 * ti_clk_add_aliases - setup clock aliases 404 * 405 * Sets up any missing clock aliases. No return value. 406 */ 407 void __init ti_clk_add_aliases(void) 408 { 409 struct device_node *np; 410 struct clk *clk; 411 412 for_each_matching_node(np, simple_clk_match_table) { 413 struct of_phandle_args clkspec; 414 415 clkspec.np = np; 416 clk = of_clk_get_from_provider(&clkspec); 417 418 ti_clk_add_alias(NULL, clk, np->name); 419 } 420 } 421 422 /** 423 * ti_clk_setup_features - setup clock features flags 424 * @features: features definition to use 425 * 426 * Initializes the clock driver features flags based on platform 427 * provided data. No return value. 428 */ 429 void __init ti_clk_setup_features(struct ti_clk_features *features) 430 { 431 memcpy(&ti_clk_features, features, sizeof(*features)); 432 } 433 434 /** 435 * ti_clk_get_features - get clock driver features flags 436 * 437 * Get TI clock driver features description. Returns a pointer 438 * to the current feature setup. 439 */ 440 const struct ti_clk_features *ti_clk_get_features(void) 441 { 442 return &ti_clk_features; 443 } 444 445 /** 446 * omap2_clk_enable_init_clocks - prepare & enable a list of clocks 447 * @clk_names: ptr to an array of strings of clock names to enable 448 * @num_clocks: number of clock names in @clk_names 449 * 450 * Prepare and enable a list of clocks, named by @clk_names. No 451 * return value. XXX Deprecated; only needed until these clocks are 452 * properly claimed and enabled by the drivers or core code that uses 453 * them. XXX What code disables & calls clk_put on these clocks? 454 */ 455 void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks) 456 { 457 struct clk *init_clk; 458 int i; 459 460 for (i = 0; i < num_clocks; i++) { 461 init_clk = clk_get(NULL, clk_names[i]); 462 if (WARN(IS_ERR(init_clk), "could not find init clock %s\n", 463 clk_names[i])) 464 continue; 465 clk_prepare_enable(init_clk); 466 } 467 } 468 469 /** 470 * ti_clk_add_alias - add a clock alias for a TI clock 471 * @dev: device alias for this clock 472 * @clk: clock handle to create alias for 473 * @con: connection ID for this clock 474 * 475 * Creates a clock alias for a TI clock. Allocates the clock lookup entry 476 * and assigns the data to it. Returns 0 if successful, negative error 477 * value otherwise. 478 */ 479 int ti_clk_add_alias(struct device *dev, struct clk *clk, const char *con) 480 { 481 struct clk_lookup *cl; 482 483 if (!clk) 484 return 0; 485 486 if (IS_ERR(clk)) 487 return PTR_ERR(clk); 488 489 cl = kzalloc(sizeof(*cl), GFP_KERNEL); 490 if (!cl) 491 return -ENOMEM; 492 493 if (dev) 494 cl->dev_id = dev_name(dev); 495 cl->con_id = con; 496 cl->clk = clk; 497 498 clkdev_add(cl); 499 500 return 0; 501 } 502 503 /** 504 * ti_clk_register - register a TI clock to the common clock framework 505 * @dev: device for this clock 506 * @hw: hardware clock handle 507 * @con: connection ID for this clock 508 * 509 * Registers a TI clock to the common clock framework, and adds a clock 510 * alias for it. Returns a handle to the registered clock if successful, 511 * ERR_PTR value in failure. 512 */ 513 struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw, 514 const char *con) 515 { 516 struct clk *clk; 517 int ret; 518 519 clk = clk_register(dev, hw); 520 if (IS_ERR(clk)) 521 return clk; 522 523 ret = ti_clk_add_alias(dev, clk, con); 524 if (ret) { 525 clk_unregister(clk); 526 return ERR_PTR(ret); 527 } 528 529 return clk; 530 } 531 532 /** 533 * ti_clk_register_omap_hw - register a clk_hw_omap to the clock framework 534 * @dev: device for this clock 535 * @hw: hardware clock handle 536 * @con: connection ID for this clock 537 * 538 * Registers a clk_hw_omap clock to the clock framewor, adds a clock alias 539 * for it, and adds the list to the available clk_hw_omap type clocks. 540 * Returns a handle to the registered clock if successful, ERR_PTR value 541 * in failure. 542 */ 543 struct clk *ti_clk_register_omap_hw(struct device *dev, struct clk_hw *hw, 544 const char *con) 545 { 546 struct clk *clk; 547 struct clk_hw_omap *oclk; 548 549 clk = ti_clk_register(dev, hw, con); 550 if (IS_ERR(clk)) 551 return clk; 552 553 oclk = to_clk_hw_omap(hw); 554 555 list_add(&oclk->node, &clk_hw_omap_clocks); 556 557 return clk; 558 } 559 560 /** 561 * omap2_clk_for_each - call function for each registered clk_hw_omap 562 * @fn: pointer to a callback function 563 * 564 * Call @fn for each registered clk_hw_omap, passing @hw to each 565 * function. @fn must return 0 for success or any other value for 566 * failure. If @fn returns non-zero, the iteration across clocks 567 * will stop and the non-zero return value will be passed to the 568 * caller of omap2_clk_for_each(). 569 */ 570 int omap2_clk_for_each(int (*fn)(struct clk_hw_omap *hw)) 571 { 572 int ret; 573 struct clk_hw_omap *hw; 574 575 list_for_each_entry(hw, &clk_hw_omap_clocks, node) { 576 ret = (*fn)(hw); 577 if (ret) 578 break; 579 } 580 581 return ret; 582 } 583 584 /** 585 * omap2_clk_is_hw_omap - check if the provided clk_hw is OMAP clock 586 * @hw: clk_hw to check if it is an omap clock or not 587 * 588 * Checks if the provided clk_hw is OMAP clock or not. Returns true if 589 * it is, false otherwise. 590 */ 591 bool omap2_clk_is_hw_omap(struct clk_hw *hw) 592 { 593 struct clk_hw_omap *oclk; 594 595 list_for_each_entry(oclk, &clk_hw_omap_clocks, node) { 596 if (&oclk->hw == hw) 597 return true; 598 } 599 600 return false; 601 } 602