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 35static LIST_HEAD(clk_hw_omap_clocks); 36struct ti_clk_ll_ops *ti_clk_ll_ops; 37static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS]; 38 39struct ti_clk_features ti_clk_features; 40 41struct clk_iomap { 42 struct regmap *regmap; 43 void __iomem *mem; 44}; 45 46static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS]; 47 48static 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 60static 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 70static 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 83static 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 */ 107int 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 */ 131void __init ti_dt_clocks_register(struct ti_dt_clk oclks[]) 132{ 133 struct ti_dt_clk *c; 134 struct device_node *node, *parent, *child; 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 child = of_get_child_by_name(parent, "clock"); 175 if (!child) 176 child = of_get_child_by_name(parent, "clk"); 177 if (child) { 178 of_node_put(parent); 179 node = child; 180 } 181 } 182 183 clkspec.np = node; 184 clkspec.args_count = num_args; 185 for (i = 0; i < num_args; i++) { 186 ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i); 187 if (ret) { 188 pr_warn("Bad tag in %s at %d: %s\n", 189 c->node_name, i, tags[i]); 190 of_node_put(node); 191 return; 192 } 193 } 194 clk = of_clk_get_from_provider(&clkspec); 195 of_node_put(node); 196 if (!IS_ERR(clk)) { 197 c->lk.clk = clk; 198 clkdev_add(&c->lk); 199 } else { 200 if (num_args && !has_clkctrl_data) { 201 struct device_node *np; 202 203 np = of_find_compatible_node(NULL, NULL, 204 "ti,clkctrl"); 205 if (np) { 206 has_clkctrl_data = true; 207 of_node_put(np); 208 } else { 209 clkctrl_nodes_missing = true; 210 211 pr_warn("missing clkctrl nodes, please update your dts.\n"); 212 continue; 213 } 214 } 215 216 pr_warn("failed to lookup clock node %s, ret=%ld\n", 217 c->node_name, PTR_ERR(clk)); 218 } 219 } 220} 221 222struct clk_init_item { 223 struct device_node *node; 224 void *user; 225 ti_of_clk_init_cb_t func; 226 struct list_head link; 227}; 228 229static LIST_HEAD(retry_list); 230 231/** 232 * ti_clk_retry_init - retries a failed clock init at later phase 233 * @node: device not for the clock 234 * @user: user data pointer 235 * @func: init function to be called for the clock 236 * 237 * Adds a failed clock init to the retry list. The retry list is parsed 238 * once all the other clocks have been initialized. 239 */ 240int __init ti_clk_retry_init(struct device_node *node, void *user, 241 ti_of_clk_init_cb_t func) 242{ 243 struct clk_init_item *retry; 244 245 pr_debug("%pOFn: adding to retry list...\n", node); 246 retry = kzalloc(sizeof(*retry), GFP_KERNEL); 247 if (!retry) 248 return -ENOMEM; 249 250 retry->node = node; 251 retry->func = func; 252 retry->user = user; 253 list_add(&retry->link, &retry_list); 254 255 return 0; 256} 257 258/** 259 * ti_clk_get_reg_addr - get register address for a clock register 260 * @node: device node for the clock 261 * @index: register index from the clock node 262 * @reg: pointer to target register struct 263 * 264 * Builds clock register address from device tree information, and returns 265 * the data via the provided output pointer @reg. Returns 0 on success, 266 * negative error value on failure. 267 */ 268int ti_clk_get_reg_addr(struct device_node *node, int index, 269 struct clk_omap_reg *reg) 270{ 271 u32 val; 272 int i; 273 274 for (i = 0; i < CLK_MAX_MEMMAPS; i++) { 275 if (clocks_node_ptr[i] == node->parent) 276 break; 277 } 278 279 if (i == CLK_MAX_MEMMAPS) { 280 pr_err("clk-provider not found for %pOFn!\n", node); 281 return -ENOENT; 282 } 283 284 reg->index = i; 285 286 if (of_property_read_u32_index(node, "reg", index, &val)) { 287 pr_err("%pOFn must have reg[%d]!\n", node, index); 288 return -EINVAL; 289 } 290 291 reg->offset = val; 292 reg->ptr = NULL; 293 294 return 0; 295} 296 297void ti_clk_latch(struct clk_omap_reg *reg, s8 shift) 298{ 299 u32 latch; 300 301 if (shift < 0) 302 return; 303 304 latch = 1 << shift; 305 306 ti_clk_ll_ops->clk_rmw(latch, latch, reg); 307 ti_clk_ll_ops->clk_rmw(0, latch, reg); 308 ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */ 309} 310 311/** 312 * omap2_clk_provider_init - init master clock provider 313 * @parent: master node 314 * @index: internal index for clk_reg_ops 315 * @syscon: syscon regmap pointer for accessing clock registers 316 * @mem: iomem pointer for the clock provider memory area, only used if 317 * syscon is not provided 318 * 319 * Initializes a master clock IP block. This basically sets up the 320 * mapping from clocks node to the memory map index. All the clocks 321 * are then initialized through the common of_clk_init call, and the 322 * clocks will access their memory maps based on the node layout. 323 * Returns 0 in success. 324 */ 325int __init omap2_clk_provider_init(struct device_node *parent, int index, 326 struct regmap *syscon, void __iomem *mem) 327{ 328 struct device_node *clocks; 329 struct clk_iomap *io; 330 331 /* get clocks for this parent */ 332 clocks = of_get_child_by_name(parent, "clocks"); 333 if (!clocks) { 334 pr_err("%pOFn missing 'clocks' child node.\n", parent); 335 return -EINVAL; 336 } 337 338 /* add clocks node info */ 339 clocks_node_ptr[index] = clocks; 340 341 io = kzalloc(sizeof(*io), GFP_KERNEL); 342 if (!io) 343 return -ENOMEM; 344 345 io->regmap = syscon; 346 io->mem = mem; 347 348 clk_memmaps[index] = io; 349 350 return 0; 351} 352 353/** 354 * omap2_clk_legacy_provider_init - initialize a legacy clock provider 355 * @index: index for the clock provider 356 * @mem: iomem pointer for the clock provider memory area 357 * 358 * Initializes a legacy clock provider memory mapping. 359 */ 360void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem) 361{ 362 struct clk_iomap *io; 363 364 io = memblock_alloc(sizeof(*io), SMP_CACHE_BYTES); 365 if (!io) 366 panic("%s: Failed to allocate %zu bytes\n", __func__, 367 sizeof(*io)); 368 369 io->mem = mem; 370 371 clk_memmaps[index] = io; 372} 373 374/** 375 * ti_dt_clk_init_retry_clks - init clocks from the retry list 376 * 377 * Initializes any clocks that have failed to initialize before, 378 * reasons being missing parent node(s) during earlier init. This 379 * typically happens only for DPLLs which need to have both of their 380 * parent clocks ready during init. 381 */ 382void ti_dt_clk_init_retry_clks(void) 383{ 384 struct clk_init_item *retry; 385 struct clk_init_item *tmp; 386 int retries = 5; 387 388 while (!list_empty(&retry_list) && retries) { 389 list_for_each_entry_safe(retry, tmp, &retry_list, link) { 390 pr_debug("retry-init: %pOFn\n", retry->node); 391 retry->func(retry->user, retry->node); 392 list_del(&retry->link); 393 kfree(retry); 394 } 395 retries--; 396 } 397} 398 399static const struct of_device_id simple_clk_match_table[] __initconst = { 400 { .compatible = "fixed-clock" }, 401 { .compatible = "fixed-factor-clock" }, 402 { } 403}; 404 405/** 406 * ti_dt_clk_name - init clock name from first output name or node name 407 * @np: device node 408 * 409 * Use the first clock-output-name for the clock name if found. Fall back 410 * to legacy naming based on node name. 411 */ 412const char *ti_dt_clk_name(struct device_node *np) 413{ 414 const char *name; 415 416 if (!of_property_read_string_index(np, "clock-output-names", 0, 417 &name)) 418 return name; 419 420 return np->name; 421} 422 423/** 424 * ti_clk_add_aliases - setup clock aliases 425 * 426 * Sets up any missing clock aliases. No return value. 427 */ 428void __init ti_clk_add_aliases(void) 429{ 430 struct device_node *np; 431 struct clk *clk; 432 433 for_each_matching_node(np, simple_clk_match_table) { 434 struct of_phandle_args clkspec; 435 436 clkspec.np = np; 437 clk = of_clk_get_from_provider(&clkspec); 438 439 ti_clk_add_alias(clk, ti_dt_clk_name(np)); 440 } 441} 442 443/** 444 * ti_clk_setup_features - setup clock features flags 445 * @features: features definition to use 446 * 447 * Initializes the clock driver features flags based on platform 448 * provided data. No return value. 449 */ 450void __init ti_clk_setup_features(struct ti_clk_features *features) 451{ 452 memcpy(&ti_clk_features, features, sizeof(*features)); 453} 454 455/** 456 * ti_clk_get_features - get clock driver features flags 457 * 458 * Get TI clock driver features description. Returns a pointer 459 * to the current feature setup. 460 */ 461const struct ti_clk_features *ti_clk_get_features(void) 462{ 463 return &ti_clk_features; 464} 465 466/** 467 * omap2_clk_enable_init_clocks - prepare & enable a list of clocks 468 * @clk_names: ptr to an array of strings of clock names to enable 469 * @num_clocks: number of clock names in @clk_names 470 * 471 * Prepare and enable a list of clocks, named by @clk_names. No 472 * return value. XXX Deprecated; only needed until these clocks are 473 * properly claimed and enabled by the drivers or core code that uses 474 * them. XXX What code disables & calls clk_put on these clocks? 475 */ 476void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks) 477{ 478 struct clk *init_clk; 479 int i; 480 481 for (i = 0; i < num_clocks; i++) { 482 init_clk = clk_get(NULL, clk_names[i]); 483 if (WARN(IS_ERR(init_clk), "could not find init clock %s\n", 484 clk_names[i])) 485 continue; 486 clk_prepare_enable(init_clk); 487 } 488} 489 490/** 491 * ti_clk_add_alias - add a clock alias for a TI clock 492 * @clk: clock handle to create alias for 493 * @con: connection ID for this clock 494 * 495 * Creates a clock alias for a TI clock. Allocates the clock lookup entry 496 * and assigns the data to it. Returns 0 if successful, negative error 497 * value otherwise. 498 */ 499int ti_clk_add_alias(struct clk *clk, const char *con) 500{ 501 struct clk_lookup *cl; 502 503 if (!clk) 504 return 0; 505 506 if (IS_ERR(clk)) 507 return PTR_ERR(clk); 508 509 cl = kzalloc(sizeof(*cl), GFP_KERNEL); 510 if (!cl) 511 return -ENOMEM; 512 513 cl->con_id = con; 514 cl->clk = clk; 515 516 clkdev_add(cl); 517 518 return 0; 519} 520 521/** 522 * of_ti_clk_register - register a TI clock to the common clock framework 523 * @node: device node for this clock 524 * @hw: hardware clock handle 525 * @con: connection ID for this clock 526 * 527 * Registers a TI clock to the common clock framework, and adds a clock 528 * alias for it. Returns a handle to the registered clock if successful, 529 * ERR_PTR value in failure. 530 */ 531struct clk *of_ti_clk_register(struct device_node *node, struct clk_hw *hw, 532 const char *con) 533{ 534 struct clk *clk; 535 int ret; 536 537 ret = of_clk_hw_register(node, hw); 538 if (ret) 539 return ERR_PTR(ret); 540 541 clk = hw->clk; 542 ret = ti_clk_add_alias(clk, con); 543 if (ret) { 544 clk_unregister(clk); 545 return ERR_PTR(ret); 546 } 547 548 return clk; 549} 550 551/** 552 * of_ti_clk_register_omap_hw - register a clk_hw_omap to the clock framework 553 * @node: device node for this clock 554 * @hw: hardware clock handle 555 * @con: connection ID for this clock 556 * 557 * Registers a clk_hw_omap clock to the clock framewor, adds a clock alias 558 * for it, and adds the list to the available clk_hw_omap type clocks. 559 * Returns a handle to the registered clock if successful, ERR_PTR value 560 * in failure. 561 */ 562struct clk *of_ti_clk_register_omap_hw(struct device_node *node, 563 struct clk_hw *hw, const char *con) 564{ 565 struct clk *clk; 566 struct clk_hw_omap *oclk; 567 568 clk = of_ti_clk_register(node, hw, con); 569 if (IS_ERR(clk)) 570 return clk; 571 572 oclk = to_clk_hw_omap(hw); 573 574 list_add(&oclk->node, &clk_hw_omap_clocks); 575 576 return clk; 577} 578 579/** 580 * omap2_clk_for_each - call function for each registered clk_hw_omap 581 * @fn: pointer to a callback function 582 * 583 * Call @fn for each registered clk_hw_omap, passing @hw to each 584 * function. @fn must return 0 for success or any other value for 585 * failure. If @fn returns non-zero, the iteration across clocks 586 * will stop and the non-zero return value will be passed to the 587 * caller of omap2_clk_for_each(). 588 */ 589int omap2_clk_for_each(int (*fn)(struct clk_hw_omap *hw)) 590{ 591 int ret; 592 struct clk_hw_omap *hw; 593 594 list_for_each_entry(hw, &clk_hw_omap_clocks, node) { 595 ret = (*fn)(hw); 596 if (ret) 597 break; 598 } 599 600 return ret; 601} 602 603/** 604 * omap2_clk_is_hw_omap - check if the provided clk_hw is OMAP clock 605 * @hw: clk_hw to check if it is an omap clock or not 606 * 607 * Checks if the provided clk_hw is OMAP clock or not. Returns true if 608 * it is, false otherwise. 609 */ 610bool omap2_clk_is_hw_omap(struct clk_hw *hw) 611{ 612 struct clk_hw_omap *oclk; 613 614 list_for_each_entry(oclk, &clk_hw_omap_clocks, node) { 615 if (&oclk->hw == hw) 616 return true; 617 } 618 619 return false; 620} 621