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/of.h> 23 #include <linux/of_address.h> 24 #include <linux/list.h> 25 #include <linux/regmap.h> 26 #include <linux/bootmem.h> 27 #include <linux/device.h> 28 29 #include "clock.h" 30 31 #undef pr_fmt 32 #define pr_fmt(fmt) "%s: " fmt, __func__ 33 34 struct ti_clk_ll_ops *ti_clk_ll_ops; 35 static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS]; 36 37 static struct ti_clk_features ti_clk_features; 38 39 struct clk_iomap { 40 struct regmap *regmap; 41 void __iomem *mem; 42 }; 43 44 static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS]; 45 46 static void clk_memmap_writel(u32 val, const struct clk_omap_reg *reg) 47 { 48 struct clk_iomap *io = clk_memmaps[reg->index]; 49 50 if (reg->ptr) 51 writel_relaxed(val, reg->ptr); 52 else if (io->regmap) 53 regmap_write(io->regmap, reg->offset, val); 54 else 55 writel_relaxed(val, io->mem + reg->offset); 56 } 57 58 static void _clk_rmw(u32 val, u32 mask, void __iomem *ptr) 59 { 60 u32 v; 61 62 v = readl_relaxed(ptr); 63 v &= ~mask; 64 v |= val; 65 writel_relaxed(v, ptr); 66 } 67 68 static void clk_memmap_rmw(u32 val, u32 mask, const struct clk_omap_reg *reg) 69 { 70 struct clk_iomap *io = clk_memmaps[reg->index]; 71 72 if (reg->ptr) { 73 _clk_rmw(val, mask, reg->ptr); 74 } else if (io->regmap) { 75 regmap_update_bits(io->regmap, reg->offset, mask, val); 76 } else { 77 _clk_rmw(val, mask, io->mem + reg->offset); 78 } 79 } 80 81 static u32 clk_memmap_readl(const struct clk_omap_reg *reg) 82 { 83 u32 val; 84 struct clk_iomap *io = clk_memmaps[reg->index]; 85 86 if (reg->ptr) 87 val = readl_relaxed(reg->ptr); 88 else if (io->regmap) 89 regmap_read(io->regmap, reg->offset, &val); 90 else 91 val = readl_relaxed(io->mem + reg->offset); 92 93 return val; 94 } 95 96 /** 97 * ti_clk_setup_ll_ops - setup low level clock operations 98 * @ops: low level clock ops descriptor 99 * 100 * Sets up low level clock operations for TI clock driver. This is used 101 * to provide various callbacks for the clock driver towards platform 102 * specific code. Returns 0 on success, -EBUSY if ll_ops have been 103 * registered already. 104 */ 105 int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops) 106 { 107 if (ti_clk_ll_ops) { 108 pr_err("Attempt to register ll_ops multiple times.\n"); 109 return -EBUSY; 110 } 111 112 ti_clk_ll_ops = ops; 113 ops->clk_readl = clk_memmap_readl; 114 ops->clk_writel = clk_memmap_writel; 115 ops->clk_rmw = clk_memmap_rmw; 116 117 return 0; 118 } 119 120 /** 121 * ti_dt_clocks_register - register DT alias clocks during boot 122 * @oclks: list of clocks to register 123 * 124 * Register alias or non-standard DT clock entries during boot. By 125 * default, DT clocks are found based on their node name. If any 126 * additional con-id / dev-id -> clock mapping is required, use this 127 * function to list these. 128 */ 129 void __init ti_dt_clocks_register(struct ti_dt_clk oclks[]) 130 { 131 struct ti_dt_clk *c; 132 struct device_node *node; 133 struct clk *clk; 134 struct of_phandle_args clkspec; 135 char buf[64]; 136 char *ptr; 137 char *tags[2]; 138 int i; 139 int num_args; 140 int ret; 141 static bool clkctrl_nodes_missing; 142 static bool has_clkctrl_data; 143 144 for (c = oclks; c->node_name != NULL; c++) { 145 strcpy(buf, c->node_name); 146 ptr = buf; 147 for (i = 0; i < 2; i++) 148 tags[i] = NULL; 149 num_args = 0; 150 while (*ptr) { 151 if (*ptr == ':') { 152 if (num_args >= 2) { 153 pr_warn("Bad number of tags on %s\n", 154 c->node_name); 155 return; 156 } 157 tags[num_args++] = ptr + 1; 158 *ptr = 0; 159 } 160 ptr++; 161 } 162 163 if (num_args && clkctrl_nodes_missing) 164 continue; 165 166 node = of_find_node_by_name(NULL, buf); 167 if (num_args) 168 node = of_find_node_by_name(node, "clk"); 169 clkspec.np = node; 170 clkspec.args_count = num_args; 171 for (i = 0; i < num_args; i++) { 172 ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i); 173 if (ret) { 174 pr_warn("Bad tag in %s at %d: %s\n", 175 c->node_name, i, tags[i]); 176 return; 177 } 178 } 179 clk = of_clk_get_from_provider(&clkspec); 180 181 if (!IS_ERR(clk)) { 182 c->lk.clk = clk; 183 clkdev_add(&c->lk); 184 } else { 185 if (num_args && !has_clkctrl_data) { 186 if (of_find_compatible_node(NULL, NULL, 187 "ti,clkctrl")) { 188 has_clkctrl_data = true; 189 } else { 190 clkctrl_nodes_missing = true; 191 192 pr_warn("missing clkctrl nodes, please update your dts.\n"); 193 continue; 194 } 195 } 196 197 pr_warn("failed to lookup clock node %s, ret=%ld\n", 198 c->node_name, PTR_ERR(clk)); 199 } 200 } 201 } 202 203 struct clk_init_item { 204 struct device_node *node; 205 void *user; 206 ti_of_clk_init_cb_t func; 207 struct list_head link; 208 }; 209 210 static LIST_HEAD(retry_list); 211 212 /** 213 * ti_clk_retry_init - retries a failed clock init at later phase 214 * @node: device not for the clock 215 * @user: user data pointer 216 * @func: init function to be called for the clock 217 * 218 * Adds a failed clock init to the retry list. The retry list is parsed 219 * once all the other clocks have been initialized. 220 */ 221 int __init ti_clk_retry_init(struct device_node *node, void *user, 222 ti_of_clk_init_cb_t func) 223 { 224 struct clk_init_item *retry; 225 226 pr_debug("%s: adding to retry list...\n", node->name); 227 retry = kzalloc(sizeof(*retry), GFP_KERNEL); 228 if (!retry) 229 return -ENOMEM; 230 231 retry->node = node; 232 retry->func = func; 233 retry->user = user; 234 list_add(&retry->link, &retry_list); 235 236 return 0; 237 } 238 239 /** 240 * ti_clk_get_reg_addr - get register address for a clock register 241 * @node: device node for the clock 242 * @index: register index from the clock node 243 * @reg: pointer to target register struct 244 * 245 * Builds clock register address from device tree information, and returns 246 * the data via the provided output pointer @reg. Returns 0 on success, 247 * negative error value on failure. 248 */ 249 int ti_clk_get_reg_addr(struct device_node *node, int index, 250 struct clk_omap_reg *reg) 251 { 252 u32 val; 253 int i; 254 255 for (i = 0; i < CLK_MAX_MEMMAPS; i++) { 256 if (clocks_node_ptr[i] == node->parent) 257 break; 258 } 259 260 if (i == CLK_MAX_MEMMAPS) { 261 pr_err("clk-provider not found for %s!\n", node->name); 262 return -ENOENT; 263 } 264 265 reg->index = i; 266 267 if (of_property_read_u32_index(node, "reg", index, &val)) { 268 pr_err("%s must have reg[%d]!\n", node->name, index); 269 return -EINVAL; 270 } 271 272 reg->offset = val; 273 reg->ptr = NULL; 274 275 return 0; 276 } 277 278 void ti_clk_latch(struct clk_omap_reg *reg, s8 shift) 279 { 280 u32 latch; 281 282 if (shift < 0) 283 return; 284 285 latch = 1 << shift; 286 287 ti_clk_ll_ops->clk_rmw(latch, latch, reg); 288 ti_clk_ll_ops->clk_rmw(0, latch, reg); 289 ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */ 290 } 291 292 /** 293 * omap2_clk_provider_init - init master clock provider 294 * @parent: master node 295 * @index: internal index for clk_reg_ops 296 * @syscon: syscon regmap pointer for accessing clock registers 297 * @mem: iomem pointer for the clock provider memory area, only used if 298 * syscon is not provided 299 * 300 * Initializes a master clock IP block. This basically sets up the 301 * mapping from clocks node to the memory map index. All the clocks 302 * are then initialized through the common of_clk_init call, and the 303 * clocks will access their memory maps based on the node layout. 304 * Returns 0 in success. 305 */ 306 int __init omap2_clk_provider_init(struct device_node *parent, int index, 307 struct regmap *syscon, void __iomem *mem) 308 { 309 struct device_node *clocks; 310 struct clk_iomap *io; 311 312 /* get clocks for this parent */ 313 clocks = of_get_child_by_name(parent, "clocks"); 314 if (!clocks) { 315 pr_err("%s missing 'clocks' child node.\n", parent->name); 316 return -EINVAL; 317 } 318 319 /* add clocks node info */ 320 clocks_node_ptr[index] = clocks; 321 322 io = kzalloc(sizeof(*io), GFP_KERNEL); 323 if (!io) 324 return -ENOMEM; 325 326 io->regmap = syscon; 327 io->mem = mem; 328 329 clk_memmaps[index] = io; 330 331 return 0; 332 } 333 334 /** 335 * omap2_clk_legacy_provider_init - initialize a legacy clock provider 336 * @index: index for the clock provider 337 * @mem: iomem pointer for the clock provider memory area 338 * 339 * Initializes a legacy clock provider memory mapping. 340 */ 341 void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem) 342 { 343 struct clk_iomap *io; 344 345 io = memblock_virt_alloc(sizeof(*io), 0); 346 347 io->mem = mem; 348 349 clk_memmaps[index] = io; 350 } 351 352 /** 353 * ti_dt_clk_init_retry_clks - init clocks from the retry list 354 * 355 * Initializes any clocks that have failed to initialize before, 356 * reasons being missing parent node(s) during earlier init. This 357 * typically happens only for DPLLs which need to have both of their 358 * parent clocks ready during init. 359 */ 360 void ti_dt_clk_init_retry_clks(void) 361 { 362 struct clk_init_item *retry; 363 struct clk_init_item *tmp; 364 int retries = 5; 365 366 while (!list_empty(&retry_list) && retries) { 367 list_for_each_entry_safe(retry, tmp, &retry_list, link) { 368 pr_debug("retry-init: %s\n", retry->node->name); 369 retry->func(retry->user, retry->node); 370 list_del(&retry->link); 371 kfree(retry); 372 } 373 retries--; 374 } 375 } 376 377 static const struct of_device_id simple_clk_match_table[] __initconst = { 378 { .compatible = "fixed-clock" }, 379 { .compatible = "fixed-factor-clock" }, 380 { } 381 }; 382 383 /** 384 * ti_clk_add_aliases - setup clock aliases 385 * 386 * Sets up any missing clock aliases. No return value. 387 */ 388 void __init ti_clk_add_aliases(void) 389 { 390 struct device_node *np; 391 struct clk *clk; 392 393 for_each_matching_node(np, simple_clk_match_table) { 394 struct of_phandle_args clkspec; 395 396 clkspec.np = np; 397 clk = of_clk_get_from_provider(&clkspec); 398 399 ti_clk_add_alias(NULL, clk, np->name); 400 } 401 } 402 403 /** 404 * ti_clk_setup_features - setup clock features flags 405 * @features: features definition to use 406 * 407 * Initializes the clock driver features flags based on platform 408 * provided data. No return value. 409 */ 410 void __init ti_clk_setup_features(struct ti_clk_features *features) 411 { 412 memcpy(&ti_clk_features, features, sizeof(*features)); 413 } 414 415 /** 416 * ti_clk_get_features - get clock driver features flags 417 * 418 * Get TI clock driver features description. Returns a pointer 419 * to the current feature setup. 420 */ 421 const struct ti_clk_features *ti_clk_get_features(void) 422 { 423 return &ti_clk_features; 424 } 425 426 /** 427 * omap2_clk_enable_init_clocks - prepare & enable a list of clocks 428 * @clk_names: ptr to an array of strings of clock names to enable 429 * @num_clocks: number of clock names in @clk_names 430 * 431 * Prepare and enable a list of clocks, named by @clk_names. No 432 * return value. XXX Deprecated; only needed until these clocks are 433 * properly claimed and enabled by the drivers or core code that uses 434 * them. XXX What code disables & calls clk_put on these clocks? 435 */ 436 void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks) 437 { 438 struct clk *init_clk; 439 int i; 440 441 for (i = 0; i < num_clocks; i++) { 442 init_clk = clk_get(NULL, clk_names[i]); 443 if (WARN(IS_ERR(init_clk), "could not find init clock %s\n", 444 clk_names[i])) 445 continue; 446 clk_prepare_enable(init_clk); 447 } 448 } 449 450 /** 451 * ti_clk_add_alias - add a clock alias for a TI clock 452 * @dev: device alias for this clock 453 * @clk: clock handle to create alias for 454 * @con: connection ID for this clock 455 * 456 * Creates a clock alias for a TI clock. Allocates the clock lookup entry 457 * and assigns the data to it. Returns 0 if successful, negative error 458 * value otherwise. 459 */ 460 int ti_clk_add_alias(struct device *dev, struct clk *clk, const char *con) 461 { 462 struct clk_lookup *cl; 463 464 if (!clk) 465 return 0; 466 467 if (IS_ERR(clk)) 468 return PTR_ERR(clk); 469 470 cl = kzalloc(sizeof(*cl), GFP_KERNEL); 471 if (!cl) 472 return -ENOMEM; 473 474 if (dev) 475 cl->dev_id = dev_name(dev); 476 cl->con_id = con; 477 cl->clk = clk; 478 479 clkdev_add(cl); 480 481 return 0; 482 } 483 484 /** 485 * ti_clk_register - register a TI clock to the common clock framework 486 * @dev: device for this clock 487 * @hw: hardware clock handle 488 * @con: connection ID for this clock 489 * 490 * Registers a TI clock to the common clock framework, and adds a clock 491 * alias for it. Returns a handle to the registered clock if successful, 492 * ERR_PTR value in failure. 493 */ 494 struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw, 495 const char *con) 496 { 497 struct clk *clk; 498 int ret; 499 500 clk = clk_register(dev, hw); 501 if (IS_ERR(clk)) 502 return clk; 503 504 ret = ti_clk_add_alias(dev, clk, con); 505 if (ret) { 506 clk_unregister(clk); 507 return ERR_PTR(ret); 508 } 509 510 return clk; 511 } 512