drivers/clk/ti/clk.c

   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 u32 clk_memmap_readl(const struct clk_omap_reg *reg)
  59 {
  60         u32 val;
  61         struct clk_iomap *io = clk_memmaps[reg->index];
  62
  63         if (reg->ptr)
  64                 val = readl_relaxed(reg->ptr);
  65         else if (io->regmap)
  66                 regmap_read(io->regmap, reg->offset, &val);
  67         else
  68                 val = readl_relaxed(io->mem + reg->offset);
  69
  70         return val;
  71 }
  72
  73 /**
  74  * ti_clk_setup_ll_ops - setup low level clock operations
  75  * @ops: low level clock ops descriptor
  76  *
  77  * Sets up low level clock operations for TI clock driver. This is used
  78  * to provide various callbacks for the clock driver towards platform
  79  * specific code. Returns 0 on success, -EBUSY if ll_ops have been
  80  * registered already.
  81  */
  82 int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops)
  83 {
  84         if (ti_clk_ll_ops) {
  85                 pr_err("Attempt to register ll_ops multiple times.\n");
  86                 return -EBUSY;
  87         }
  88
  89         ti_clk_ll_ops = ops;
  90         ops->clk_readl = clk_memmap_readl;
  91         ops->clk_writel = clk_memmap_writel;
  92
  93         return 0;
  94 }
  95
  96 /**
  97  * ti_dt_clocks_register - register DT alias clocks during boot
  98  * @oclks: list of clocks to register
  99  *
 100  * Register alias or non-standard DT clock entries during boot. By
 101  * default, DT clocks are found based on their node name. If any
 102  * additional con-id / dev-id -> clock mapping is required, use this
 103  * function to list these.
 104  */
 105 void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
 106 {
 107         struct ti_dt_clk *c;
 108         struct device_node *node;
 109         struct clk *clk;
 110         struct of_phandle_args clkspec;
 111
 112         for (c = oclks; c->node_name != NULL; c++) {
 113                 node = of_find_node_by_name(NULL, c->node_name);
 114                 clkspec.np = node;
 115                 clk = of_clk_get_from_provider(&clkspec);
 116
 117                 if (!IS_ERR(clk)) {
 118                         c->lk.clk = clk;
 119                         clkdev_add(&c->lk);
 120                 } else {
 121                         pr_warn("failed to lookup clock node %s\n",
 122                                 c->node_name);
 123                 }
 124         }
 125 }
 126
 127 struct clk_init_item {
 128         struct device_node *node;
 129         struct clk_hw *hw;
 130         ti_of_clk_init_cb_t func;
 131         struct list_head link;
 132 };
 133
 134 static LIST_HEAD(retry_list);
 135
 136 /**
 137  * ti_clk_retry_init - retries a failed clock init at later phase
 138  * @node: device not for the clock
 139  * @hw: partially initialized clk_hw struct for the clock
 140  * @func: init function to be called for the clock
 141  *
 142  * Adds a failed clock init to the retry list. The retry list is parsed
 143  * once all the other clocks have been initialized.
 144  */
 145 int __init ti_clk_retry_init(struct device_node *node, struct clk_hw *hw,
 146                               ti_of_clk_init_cb_t func)
 147 {
 148         struct clk_init_item *retry;
 149
 150         pr_debug("%s: adding to retry list...\n", node->name);
 151         retry = kzalloc(sizeof(*retry), GFP_KERNEL);
 152         if (!retry)
 153                 return -ENOMEM;
 154
 155         retry->node = node;
 156         retry->func = func;
 157         retry->hw = hw;
 158         list_add(&retry->link, &retry_list);
 159
 160         return 0;
 161 }
 162
 163 /**
 164  * ti_clk_get_reg_addr - get register address for a clock register
 165  * @node: device node for the clock
 166  * @index: register index from the clock node
 167  * @reg: pointer to target register struct
 168  *
 169  * Builds clock register address from device tree information, and returns
 170  * the data via the provided output pointer @reg. Returns 0 on success,
 171  * negative error value on failure.
 172  */
 173 int ti_clk_get_reg_addr(struct device_node *node, int index,
 174                         struct clk_omap_reg *reg)
 175 {
 176         u32 val;
 177         int i;
 178
 179         for (i = 0; i < CLK_MAX_MEMMAPS; i++) {
 180                 if (clocks_node_ptr[i] == node->parent)
 181                         break;
 182         }
 183
 184         if (i == CLK_MAX_MEMMAPS) {
 185                 pr_err("clk-provider not found for %s!\n", node->name);
 186                 return -ENOENT;
 187         }
 188
 189         reg->index = i;
 190
 191         if (of_property_read_u32_index(node, "reg", index, &val)) {
 192                 pr_err("%s must have reg[%d]!\n", node->name, index);
 193                 return -EINVAL;
 194         }
 195
 196         reg->offset = val;
 197         reg->ptr = NULL;
 198
 199         return 0;
 200 }
 201
 202 /**
 203  * omap2_clk_provider_init - init master clock provider
 204  * @parent: master node
 205  * @index: internal index for clk_reg_ops
 206  * @syscon: syscon regmap pointer for accessing clock registers
 207  * @mem: iomem pointer for the clock provider memory area, only used if
 208  *       syscon is not provided
 209  *
 210  * Initializes a master clock IP block. This basically sets up the
 211  * mapping from clocks node to the memory map index. All the clocks
 212  * are then initialized through the common of_clk_init call, and the
 213  * clocks will access their memory maps based on the node layout.
 214  * Returns 0 in success.
 215  */
 216 int __init omap2_clk_provider_init(struct device_node *parent, int index,
 217                                    struct regmap *syscon, void __iomem *mem)
 218 {
 219         struct device_node *clocks;
 220         struct clk_iomap *io;
 221
 222         /* get clocks for this parent */
 223         clocks = of_get_child_by_name(parent, "clocks");
 224         if (!clocks) {
 225                 pr_err("%s missing 'clocks' child node.\n", parent->name);
 226                 return -EINVAL;
 227         }
 228
 229         /* add clocks node info */
 230         clocks_node_ptr[index] = clocks;
 231
 232         io = kzalloc(sizeof(*io), GFP_KERNEL);
 233         if (!io)
 234                 return -ENOMEM;
 235
 236         io->regmap = syscon;
 237         io->mem = mem;
 238
 239         clk_memmaps[index] = io;
 240
 241         return 0;
 242 }
 243
 244 /**
 245  * omap2_clk_legacy_provider_init - initialize a legacy clock provider
 246  * @index: index for the clock provider
 247  * @mem: iomem pointer for the clock provider memory area
 248  *
 249  * Initializes a legacy clock provider memory mapping.
 250  */
 251 void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)
 252 {
 253         struct clk_iomap *io;
 254
 255         io = memblock_virt_alloc(sizeof(*io), 0);
 256
 257         io->mem = mem;
 258
 259         clk_memmaps[index] = io;
 260 }
 261
 262 /**
 263  * ti_dt_clk_init_retry_clks - init clocks from the retry list
 264  *
 265  * Initializes any clocks that have failed to initialize before,
 266  * reasons being missing parent node(s) during earlier init. This
 267  * typically happens only for DPLLs which need to have both of their
 268  * parent clocks ready during init.
 269  */
 270 void ti_dt_clk_init_retry_clks(void)
 271 {
 272         struct clk_init_item *retry;
 273         struct clk_init_item *tmp;
 274         int retries = 5;
 275
 276         while (!list_empty(&retry_list) && retries) {
 277                 list_for_each_entry_safe(retry, tmp, &retry_list, link) {
 278                         pr_debug("retry-init: %s\n", retry->node->name);
 279                         retry->func(retry->hw, retry->node);
 280                         list_del(&retry->link);
 281                         kfree(retry);
 282                 }
 283                 retries--;
 284         }
 285 }
 286
 287 #if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_ATAGS)
 288 void __init ti_clk_patch_legacy_clks(struct ti_clk **patch)
 289 {
 290         while (*patch) {
 291                 memcpy((*patch)->patch, *patch, sizeof(**patch));
 292                 patch++;
 293         }
 294 }
 295
 296 struct clk __init *ti_clk_register_clk(struct ti_clk *setup)
 297 {
 298         struct clk *clk;
 299         struct ti_clk_fixed *fixed;
 300         struct ti_clk_fixed_factor *fixed_factor;
 301         struct clk_hw *clk_hw;
 302         int ret;
 303
 304         if (setup->clk)
 305                 return setup->clk;
 306
 307         switch (setup->type) {
 308         case TI_CLK_FIXED:
 309                 fixed = setup->data;
 310
 311                 clk = clk_register_fixed_rate(NULL, setup->name, NULL, 0,
 312                                               fixed->frequency);
 313                 if (!IS_ERR(clk)) {
 314                         ret = ti_clk_add_alias(NULL, clk, setup->name);
 315                         if (ret) {
 316                                 clk_unregister(clk);
 317                                 clk = ERR_PTR(ret);
 318                         }
 319                 }
 320                 break;
 321         case TI_CLK_MUX:
 322                 clk = ti_clk_register_mux(setup);
 323                 break;
 324         case TI_CLK_DIVIDER:
 325                 clk = ti_clk_register_divider(setup);
 326                 break;
 327         case TI_CLK_COMPOSITE:
 328                 clk = ti_clk_register_composite(setup);
 329                 break;
 330         case TI_CLK_FIXED_FACTOR:
 331                 fixed_factor = setup->data;
 332
 333                 clk = clk_register_fixed_factor(NULL, setup->name,
 334                                                 fixed_factor->parent,
 335                                                 0, fixed_factor->mult,
 336                                                 fixed_factor->div);
 337                 if (!IS_ERR(clk)) {
 338                         ret = ti_clk_add_alias(NULL, clk, setup->name);
 339                         if (ret) {
 340                                 clk_unregister(clk);
 341                                 clk = ERR_PTR(ret);
 342                         }
 343                 }
 344                 break;
 345         case TI_CLK_GATE:
 346                 clk = ti_clk_register_gate(setup);
 347                 break;
 348         case TI_CLK_DPLL:
 349                 clk = ti_clk_register_dpll(setup);
 350                 break;
 351         default:
 352                 pr_err("bad type for %s!\n", setup->name);
 353                 clk = ERR_PTR(-EINVAL);
 354         }
 355
 356         if (!IS_ERR(clk)) {
 357                 setup->clk = clk;
 358                 if (setup->clkdm_name) {
 359                         clk_hw = __clk_get_hw(clk);
 360                         if (clk_hw_get_flags(clk_hw) & CLK_IS_BASIC) {
 361                                 pr_warn("can't setup clkdm for basic clk %s\n",
 362                                         setup->name);
 363                         } else {
 364                                 to_clk_hw_omap(clk_hw)->clkdm_name =
 365                                         setup->clkdm_name;
 366                                 omap2_init_clk_clkdm(clk_hw);
 367                         }
 368                 }
 369         }
 370
 371         return clk;
 372 }
 373
 374 int __init ti_clk_register_legacy_clks(struct ti_clk_alias *clks)
 375 {
 376         struct clk *clk;
 377         bool retry;
 378         struct ti_clk_alias *retry_clk;
 379         struct ti_clk_alias *tmp;
 380
 381         while (clks->clk) {
 382                 clk = ti_clk_register_clk(clks->clk);
 383                 if (IS_ERR(clk)) {
 384                         if (PTR_ERR(clk) == -EAGAIN) {
 385                                 list_add(&clks->link, &retry_list);
 386                         } else {
 387                                 pr_err("register for %s failed: %ld\n",
 388                                        clks->clk->name, PTR_ERR(clk));
 389                                 return PTR_ERR(clk);
 390                         }
 391                 }
 392                 clks++;
 393         }
 394
 395         retry = true;
 396
 397         while (!list_empty(&retry_list) && retry) {
 398                 retry = false;
 399                 list_for_each_entry_safe(retry_clk, tmp, &retry_list, link) {
 400                         pr_debug("retry-init: %s\n", retry_clk->clk->name);
 401                         clk = ti_clk_register_clk(retry_clk->clk);
 402                         if (IS_ERR(clk)) {
 403                                 if (PTR_ERR(clk) == -EAGAIN) {
 404                                         continue;
 405                                 } else {
 406                                         pr_err("register for %s failed: %ld\n",
 407                                                retry_clk->clk->name,
 408                                                PTR_ERR(clk));
 409                                         return PTR_ERR(clk);
 410                                 }
 411                         } else {
 412                                 retry = true;
 413                                 list_del(&retry_clk->link);
 414                         }
 415                 }
 416         }
 417
 418         return 0;
 419 }
 420 #endif
 421
 422 static const struct of_device_id simple_clk_match_table[] __initconst = {
 423         { .compatible = "fixed-clock" },
 424         { .compatible = "fixed-factor-clock" },
 425         { }
 426 };
 427
 428 /**
 429  * ti_clk_add_aliases - setup clock aliases
 430  *
 431  * Sets up any missing clock aliases. No return value.
 432  */
 433 void __init ti_clk_add_aliases(void)
 434 {
 435         struct device_node *np;
 436         struct clk *clk;
 437
 438         for_each_matching_node(np, simple_clk_match_table) {
 439                 struct of_phandle_args clkspec;
 440
 441                 clkspec.np = np;
 442                 clk = of_clk_get_from_provider(&clkspec);
 443
 444                 ti_clk_add_alias(NULL, clk, np->name);
 445         }
 446 }
 447
 448 /**
 449  * ti_clk_setup_features - setup clock features flags
 450  * @features: features definition to use
 451  *
 452  * Initializes the clock driver features flags based on platform
 453  * provided data. No return value.
 454  */
 455 void __init ti_clk_setup_features(struct ti_clk_features *features)
 456 {
 457         memcpy(&ti_clk_features, features, sizeof(*features));
 458 }
 459
 460 /**
 461  * ti_clk_get_features - get clock driver features flags
 462  *
 463  * Get TI clock driver features description. Returns a pointer
 464  * to the current feature setup.
 465  */
 466 const struct ti_clk_features *ti_clk_get_features(void)
 467 {
 468         return &ti_clk_features;
 469 }
 470
 471 /**
 472  * omap2_clk_enable_init_clocks - prepare & enable a list of clocks
 473  * @clk_names: ptr to an array of strings of clock names to enable
 474  * @num_clocks: number of clock names in @clk_names
 475  *
 476  * Prepare and enable a list of clocks, named by @clk_names.  No
 477  * return value. XXX Deprecated; only needed until these clocks are
 478  * properly claimed and enabled by the drivers or core code that uses
 479  * them.  XXX What code disables & calls clk_put on these clocks?
 480  */
 481 void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)
 482 {
 483         struct clk *init_clk;
 484         int i;
 485
 486         for (i = 0; i < num_clocks; i++) {
 487                 init_clk = clk_get(NULL, clk_names[i]);
 488                 if (WARN(IS_ERR(init_clk), "could not find init clock %s\n",
 489                          clk_names[i]))
 490                         continue;
 491                 clk_prepare_enable(init_clk);
 492         }
 493 }
 494
 495 /**
 496  * ti_clk_add_alias - add a clock alias for a TI clock
 497  * @dev: device alias for this clock
 498  * @clk: clock handle to create alias for
 499  * @con: connection ID for this clock
 500  *
 501  * Creates a clock alias for a TI clock. Allocates the clock lookup entry
 502  * and assigns the data to it. Returns 0 if successful, negative error
 503  * value otherwise.
 504  */
 505 int ti_clk_add_alias(struct device *dev, struct clk *clk, const char *con)
 506 {
 507         struct clk_lookup *cl;
 508
 509         if (!clk)
 510                 return 0;
 511
 512         if (IS_ERR(clk))
 513                 return PTR_ERR(clk);
 514
 515         cl = kzalloc(sizeof(*cl), GFP_KERNEL);
 516         if (!cl)
 517                 return -ENOMEM;
 518
 519         if (dev)
 520                 cl->dev_id = dev_name(dev);
 521         cl->con_id = con;
 522         cl->clk = clk;
 523
 524         clkdev_add(cl);
 525
 526         return 0;
 527 }
 528
 529 /**
 530  * ti_clk_register - register a TI clock to the common clock framework
 531  * @dev: device for this clock
 532  * @hw: hardware clock handle
 533  * @con: connection ID for this clock
 534  *
 535  * Registers a TI clock to the common clock framework, and adds a clock
 536  * alias for it. Returns a handle to the registered clock if successful,
 537  * ERR_PTR value in failure.
 538  */
 539 struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw,
 540                             const char *con)
 541 {
 542         struct clk *clk;
 543         int ret;
 544
 545         clk = clk_register(dev, hw);
 546         if (IS_ERR(clk))
 547                 return clk;
 548
 549         ret = ti_clk_add_alias(dev, clk, con);
 550         if (ret) {
 551                 clk_unregister(clk);
 552                 return ERR_PTR(ret);
 553         }
 554
 555         return clk;
 556 }