Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 1 | /* |
Paul Mundt | de9186c | 2010-10-18 21:32:58 +0900 | [diff] [blame] | 2 | * SuperH clock framework |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 3 | * |
Paul Mundt | 960bc36 | 2010-08-20 19:10:38 +0900 | [diff] [blame] | 4 | * Copyright (C) 2005 - 2010 Paul Mundt |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 5 | * |
| 6 | * This clock framework is derived from the OMAP version by: |
| 7 | * |
| 8 | * Copyright (C) 2004 - 2008 Nokia Corporation |
| 9 | * Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com> |
| 10 | * |
| 11 | * Modified for omap shared clock framework by Tony Lindgren <tony@atomide.com> |
| 12 | * |
| 13 | * This file is subject to the terms and conditions of the GNU General Public |
| 14 | * License. See the file "COPYING" in the main directory of this archive |
| 15 | * for more details. |
| 16 | */ |
Paul Mundt | 550a1ef | 2010-10-13 19:24:55 +0900 | [diff] [blame] | 17 | #define pr_fmt(fmt) "clock: " fmt |
| 18 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 19 | #include <linux/kernel.h> |
| 20 | #include <linux/init.h> |
| 21 | #include <linux/module.h> |
| 22 | #include <linux/mutex.h> |
| 23 | #include <linux/list.h> |
| 24 | #include <linux/kobject.h> |
| 25 | #include <linux/sysdev.h> |
| 26 | #include <linux/seq_file.h> |
| 27 | #include <linux/err.h> |
Paul Mundt | 28085bc | 2010-10-15 16:46:37 +0900 | [diff] [blame] | 28 | #include <linux/io.h> |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 29 | #include <linux/debugfs.h> |
| 30 | #include <linux/cpufreq.h> |
| 31 | #include <linux/clk.h> |
| 32 | #include <linux/sh_clk.h> |
| 33 | |
| 34 | static LIST_HEAD(clock_list); |
| 35 | static DEFINE_SPINLOCK(clock_lock); |
| 36 | static DEFINE_MUTEX(clock_list_sem); |
| 37 | |
| 38 | void clk_rate_table_build(struct clk *clk, |
| 39 | struct cpufreq_frequency_table *freq_table, |
| 40 | int nr_freqs, |
| 41 | struct clk_div_mult_table *src_table, |
| 42 | unsigned long *bitmap) |
| 43 | { |
| 44 | unsigned long mult, div; |
| 45 | unsigned long freq; |
| 46 | int i; |
| 47 | |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 48 | clk->nr_freqs = nr_freqs; |
| 49 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 50 | for (i = 0; i < nr_freqs; i++) { |
| 51 | div = 1; |
| 52 | mult = 1; |
| 53 | |
| 54 | if (src_table->divisors && i < src_table->nr_divisors) |
| 55 | div = src_table->divisors[i]; |
| 56 | |
| 57 | if (src_table->multipliers && i < src_table->nr_multipliers) |
| 58 | mult = src_table->multipliers[i]; |
| 59 | |
| 60 | if (!div || !mult || (bitmap && !test_bit(i, bitmap))) |
| 61 | freq = CPUFREQ_ENTRY_INVALID; |
| 62 | else |
| 63 | freq = clk->parent->rate * mult / div; |
| 64 | |
| 65 | freq_table[i].index = i; |
| 66 | freq_table[i].frequency = freq; |
| 67 | } |
| 68 | |
| 69 | /* Termination entry */ |
| 70 | freq_table[i].index = i; |
| 71 | freq_table[i].frequency = CPUFREQ_TABLE_END; |
| 72 | } |
| 73 | |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 74 | struct clk_rate_round_data; |
| 75 | |
| 76 | struct clk_rate_round_data { |
| 77 | unsigned long rate; |
| 78 | unsigned int min, max; |
Paul Mundt | 8e122db | 2010-10-15 18:33:24 +0900 | [diff] [blame] | 79 | long (*func)(unsigned int, struct clk_rate_round_data *); |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 80 | void *arg; |
| 81 | }; |
| 82 | |
| 83 | #define for_each_frequency(pos, r, freq) \ |
Paul Mundt | e5690e0 | 2010-10-16 00:51:05 +0900 | [diff] [blame] | 84 | for (pos = r->min, freq = r->func(pos, r); \ |
Kuninori Morimoto | c2590f4 | 2010-10-18 03:50:29 +0000 | [diff] [blame] | 85 | pos <= r->max; pos++, freq = r->func(pos, r)) \ |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 86 | if (unlikely(freq == 0)) \ |
| 87 | ; \ |
| 88 | else |
| 89 | |
| 90 | static long clk_rate_round_helper(struct clk_rate_round_data *rounder) |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 91 | { |
| 92 | unsigned long rate_error, rate_error_prev = ~0UL; |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 93 | unsigned long highest, lowest, freq; |
Paul Mundt | 5aefa34 | 2010-11-01 15:30:31 -0400 | [diff] [blame] | 94 | long rate_best_fit = -ENOENT; |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 95 | int i; |
| 96 | |
Paul Mundt | 960bc36 | 2010-08-20 19:10:38 +0900 | [diff] [blame] | 97 | highest = 0; |
| 98 | lowest = ~0UL; |
| 99 | |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 100 | for_each_frequency(i, rounder, freq) { |
Paul Mundt | 960bc36 | 2010-08-20 19:10:38 +0900 | [diff] [blame] | 101 | if (freq > highest) |
| 102 | highest = freq; |
| 103 | if (freq < lowest) |
| 104 | lowest = freq; |
| 105 | |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 106 | rate_error = abs(freq - rounder->rate); |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 107 | if (rate_error < rate_error_prev) { |
| 108 | rate_best_fit = freq; |
| 109 | rate_error_prev = rate_error; |
| 110 | } |
| 111 | |
| 112 | if (rate_error == 0) |
| 113 | break; |
| 114 | } |
| 115 | |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 116 | if (rounder->rate >= highest) |
Paul Mundt | 960bc36 | 2010-08-20 19:10:38 +0900 | [diff] [blame] | 117 | rate_best_fit = highest; |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 118 | if (rounder->rate <= lowest) |
Paul Mundt | 960bc36 | 2010-08-20 19:10:38 +0900 | [diff] [blame] | 119 | rate_best_fit = lowest; |
| 120 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 121 | return rate_best_fit; |
| 122 | } |
| 123 | |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 124 | static long clk_rate_table_iter(unsigned int pos, |
| 125 | struct clk_rate_round_data *rounder) |
| 126 | { |
| 127 | struct cpufreq_frequency_table *freq_table = rounder->arg; |
| 128 | unsigned long freq = freq_table[pos].frequency; |
| 129 | |
| 130 | if (freq == CPUFREQ_ENTRY_INVALID) |
| 131 | freq = 0; |
| 132 | |
| 133 | return freq; |
| 134 | } |
| 135 | |
| 136 | long clk_rate_table_round(struct clk *clk, |
| 137 | struct cpufreq_frequency_table *freq_table, |
| 138 | unsigned long rate) |
| 139 | { |
| 140 | struct clk_rate_round_data table_round = { |
| 141 | .min = 0, |
Kuninori Morimoto | c2590f4 | 2010-10-18 03:50:29 +0000 | [diff] [blame] | 142 | .max = clk->nr_freqs - 1, |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 143 | .func = clk_rate_table_iter, |
| 144 | .arg = freq_table, |
| 145 | .rate = rate, |
| 146 | }; |
| 147 | |
Kuninori Morimoto | c2590f4 | 2010-10-18 03:50:29 +0000 | [diff] [blame] | 148 | if (clk->nr_freqs < 1) |
Paul Mundt | 5aefa34 | 2010-11-01 15:30:31 -0400 | [diff] [blame] | 149 | return -ENOSYS; |
Kuninori Morimoto | c2590f4 | 2010-10-18 03:50:29 +0000 | [diff] [blame] | 150 | |
Paul Mundt | f586903 | 2010-10-15 18:17:35 +0900 | [diff] [blame] | 151 | return clk_rate_round_helper(&table_round); |
| 152 | } |
| 153 | |
Paul Mundt | 8e122db | 2010-10-15 18:33:24 +0900 | [diff] [blame] | 154 | static long clk_rate_div_range_iter(unsigned int pos, |
| 155 | struct clk_rate_round_data *rounder) |
| 156 | { |
| 157 | return clk_get_rate(rounder->arg) / pos; |
| 158 | } |
| 159 | |
| 160 | long clk_rate_div_range_round(struct clk *clk, unsigned int div_min, |
| 161 | unsigned int div_max, unsigned long rate) |
| 162 | { |
| 163 | struct clk_rate_round_data div_range_round = { |
| 164 | .min = div_min, |
| 165 | .max = div_max, |
| 166 | .func = clk_rate_div_range_iter, |
| 167 | .arg = clk_get_parent(clk), |
| 168 | .rate = rate, |
| 169 | }; |
| 170 | |
| 171 | return clk_rate_round_helper(&div_range_round); |
| 172 | } |
| 173 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 174 | int clk_rate_table_find(struct clk *clk, |
| 175 | struct cpufreq_frequency_table *freq_table, |
| 176 | unsigned long rate) |
| 177 | { |
| 178 | int i; |
| 179 | |
| 180 | for (i = 0; freq_table[i].frequency != CPUFREQ_TABLE_END; i++) { |
| 181 | unsigned long freq = freq_table[i].frequency; |
| 182 | |
| 183 | if (freq == CPUFREQ_ENTRY_INVALID) |
| 184 | continue; |
| 185 | |
| 186 | if (freq == rate) |
| 187 | return i; |
| 188 | } |
| 189 | |
| 190 | return -ENOENT; |
| 191 | } |
| 192 | |
| 193 | /* Used for clocks that always have same value as the parent clock */ |
| 194 | unsigned long followparent_recalc(struct clk *clk) |
| 195 | { |
| 196 | return clk->parent ? clk->parent->rate : 0; |
| 197 | } |
| 198 | |
| 199 | int clk_reparent(struct clk *child, struct clk *parent) |
| 200 | { |
| 201 | list_del_init(&child->sibling); |
| 202 | if (parent) |
| 203 | list_add(&child->sibling, &parent->children); |
| 204 | child->parent = parent; |
| 205 | |
| 206 | /* now do the debugfs renaming to reattach the child |
| 207 | to the proper parent */ |
| 208 | |
| 209 | return 0; |
| 210 | } |
| 211 | |
| 212 | /* Propagate rate to children */ |
| 213 | void propagate_rate(struct clk *tclk) |
| 214 | { |
| 215 | struct clk *clkp; |
| 216 | |
| 217 | list_for_each_entry(clkp, &tclk->children, sibling) { |
| 218 | if (clkp->ops && clkp->ops->recalc) |
| 219 | clkp->rate = clkp->ops->recalc(clkp); |
| 220 | |
| 221 | propagate_rate(clkp); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | static void __clk_disable(struct clk *clk) |
| 226 | { |
Magnus Damm | 6939539 | 2010-10-13 07:44:36 +0000 | [diff] [blame] | 227 | if (WARN(!clk->usecount, "Trying to disable clock %p with 0 usecount\n", |
| 228 | clk)) |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 229 | return; |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 230 | |
| 231 | if (!(--clk->usecount)) { |
| 232 | if (likely(clk->ops && clk->ops->disable)) |
| 233 | clk->ops->disable(clk); |
| 234 | if (likely(clk->parent)) |
| 235 | __clk_disable(clk->parent); |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | void clk_disable(struct clk *clk) |
| 240 | { |
| 241 | unsigned long flags; |
| 242 | |
| 243 | if (!clk) |
| 244 | return; |
| 245 | |
| 246 | spin_lock_irqsave(&clock_lock, flags); |
| 247 | __clk_disable(clk); |
| 248 | spin_unlock_irqrestore(&clock_lock, flags); |
| 249 | } |
| 250 | EXPORT_SYMBOL_GPL(clk_disable); |
| 251 | |
| 252 | static int __clk_enable(struct clk *clk) |
| 253 | { |
| 254 | int ret = 0; |
| 255 | |
| 256 | if (clk->usecount++ == 0) { |
| 257 | if (clk->parent) { |
| 258 | ret = __clk_enable(clk->parent); |
| 259 | if (unlikely(ret)) |
| 260 | goto err; |
| 261 | } |
| 262 | |
| 263 | if (clk->ops && clk->ops->enable) { |
| 264 | ret = clk->ops->enable(clk); |
| 265 | if (ret) { |
| 266 | if (clk->parent) |
| 267 | __clk_disable(clk->parent); |
| 268 | goto err; |
| 269 | } |
| 270 | } |
| 271 | } |
| 272 | |
| 273 | return ret; |
| 274 | err: |
| 275 | clk->usecount--; |
| 276 | return ret; |
| 277 | } |
| 278 | |
| 279 | int clk_enable(struct clk *clk) |
| 280 | { |
| 281 | unsigned long flags; |
| 282 | int ret; |
| 283 | |
| 284 | if (!clk) |
| 285 | return -EINVAL; |
| 286 | |
| 287 | spin_lock_irqsave(&clock_lock, flags); |
| 288 | ret = __clk_enable(clk); |
| 289 | spin_unlock_irqrestore(&clock_lock, flags); |
| 290 | |
| 291 | return ret; |
| 292 | } |
| 293 | EXPORT_SYMBOL_GPL(clk_enable); |
| 294 | |
| 295 | static LIST_HEAD(root_clks); |
| 296 | |
| 297 | /** |
| 298 | * recalculate_root_clocks - recalculate and propagate all root clocks |
| 299 | * |
| 300 | * Recalculates all root clocks (clocks with no parent), which if the |
| 301 | * clock's .recalc is set correctly, should also propagate their rates. |
| 302 | * Called at init. |
| 303 | */ |
| 304 | void recalculate_root_clocks(void) |
| 305 | { |
| 306 | struct clk *clkp; |
| 307 | |
| 308 | list_for_each_entry(clkp, &root_clks, sibling) { |
| 309 | if (clkp->ops && clkp->ops->recalc) |
| 310 | clkp->rate = clkp->ops->recalc(clkp); |
| 311 | propagate_rate(clkp); |
| 312 | } |
| 313 | } |
| 314 | |
Paul Mundt | 28085bc | 2010-10-15 16:46:37 +0900 | [diff] [blame] | 315 | static struct clk_mapping dummy_mapping; |
| 316 | |
| 317 | static struct clk *lookup_root_clock(struct clk *clk) |
| 318 | { |
| 319 | while (clk->parent) |
| 320 | clk = clk->parent; |
| 321 | |
| 322 | return clk; |
| 323 | } |
| 324 | |
| 325 | static int clk_establish_mapping(struct clk *clk) |
| 326 | { |
| 327 | struct clk_mapping *mapping = clk->mapping; |
| 328 | |
| 329 | /* |
| 330 | * Propagate mappings. |
| 331 | */ |
| 332 | if (!mapping) { |
| 333 | struct clk *clkp; |
| 334 | |
| 335 | /* |
| 336 | * dummy mapping for root clocks with no specified ranges |
| 337 | */ |
| 338 | if (!clk->parent) { |
| 339 | clk->mapping = &dummy_mapping; |
| 340 | return 0; |
| 341 | } |
| 342 | |
| 343 | /* |
| 344 | * If we're on a child clock and it provides no mapping of its |
| 345 | * own, inherit the mapping from its root clock. |
| 346 | */ |
| 347 | clkp = lookup_root_clock(clk); |
| 348 | mapping = clkp->mapping; |
| 349 | BUG_ON(!mapping); |
| 350 | } |
| 351 | |
| 352 | /* |
| 353 | * Establish initial mapping. |
| 354 | */ |
| 355 | if (!mapping->base && mapping->phys) { |
| 356 | kref_init(&mapping->ref); |
| 357 | |
| 358 | mapping->base = ioremap_nocache(mapping->phys, mapping->len); |
| 359 | if (unlikely(!mapping->base)) |
| 360 | return -ENXIO; |
| 361 | } else if (mapping->base) { |
| 362 | /* |
| 363 | * Bump the refcount for an existing mapping |
| 364 | */ |
| 365 | kref_get(&mapping->ref); |
| 366 | } |
| 367 | |
| 368 | clk->mapping = mapping; |
| 369 | return 0; |
| 370 | } |
| 371 | |
| 372 | static void clk_destroy_mapping(struct kref *kref) |
| 373 | { |
| 374 | struct clk_mapping *mapping; |
| 375 | |
| 376 | mapping = container_of(kref, struct clk_mapping, ref); |
| 377 | |
| 378 | iounmap(mapping->base); |
| 379 | } |
| 380 | |
| 381 | static void clk_teardown_mapping(struct clk *clk) |
| 382 | { |
| 383 | struct clk_mapping *mapping = clk->mapping; |
| 384 | |
| 385 | /* Nothing to do */ |
| 386 | if (mapping == &dummy_mapping) |
| 387 | return; |
| 388 | |
| 389 | kref_put(&mapping->ref, clk_destroy_mapping); |
| 390 | clk->mapping = NULL; |
| 391 | } |
| 392 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 393 | int clk_register(struct clk *clk) |
| 394 | { |
Paul Mundt | 28085bc | 2010-10-15 16:46:37 +0900 | [diff] [blame] | 395 | int ret; |
| 396 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 397 | if (clk == NULL || IS_ERR(clk)) |
| 398 | return -EINVAL; |
| 399 | |
| 400 | /* |
| 401 | * trap out already registered clocks |
| 402 | */ |
| 403 | if (clk->node.next || clk->node.prev) |
| 404 | return 0; |
| 405 | |
| 406 | mutex_lock(&clock_list_sem); |
| 407 | |
| 408 | INIT_LIST_HEAD(&clk->children); |
| 409 | clk->usecount = 0; |
| 410 | |
Paul Mundt | 28085bc | 2010-10-15 16:46:37 +0900 | [diff] [blame] | 411 | ret = clk_establish_mapping(clk); |
| 412 | if (unlikely(ret)) |
| 413 | goto out_unlock; |
| 414 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 415 | if (clk->parent) |
| 416 | list_add(&clk->sibling, &clk->parent->children); |
| 417 | else |
| 418 | list_add(&clk->sibling, &root_clks); |
| 419 | |
| 420 | list_add(&clk->node, &clock_list); |
| 421 | if (clk->ops && clk->ops->init) |
| 422 | clk->ops->init(clk); |
Paul Mundt | 28085bc | 2010-10-15 16:46:37 +0900 | [diff] [blame] | 423 | |
| 424 | out_unlock: |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 425 | mutex_unlock(&clock_list_sem); |
| 426 | |
Paul Mundt | 28085bc | 2010-10-15 16:46:37 +0900 | [diff] [blame] | 427 | return ret; |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 428 | } |
| 429 | EXPORT_SYMBOL_GPL(clk_register); |
| 430 | |
| 431 | void clk_unregister(struct clk *clk) |
| 432 | { |
| 433 | mutex_lock(&clock_list_sem); |
| 434 | list_del(&clk->sibling); |
| 435 | list_del(&clk->node); |
Paul Mundt | 28085bc | 2010-10-15 16:46:37 +0900 | [diff] [blame] | 436 | clk_teardown_mapping(clk); |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 437 | mutex_unlock(&clock_list_sem); |
| 438 | } |
| 439 | EXPORT_SYMBOL_GPL(clk_unregister); |
| 440 | |
| 441 | void clk_enable_init_clocks(void) |
| 442 | { |
| 443 | struct clk *clkp; |
| 444 | |
| 445 | list_for_each_entry(clkp, &clock_list, node) |
| 446 | if (clkp->flags & CLK_ENABLE_ON_INIT) |
| 447 | clk_enable(clkp); |
| 448 | } |
| 449 | |
| 450 | unsigned long clk_get_rate(struct clk *clk) |
| 451 | { |
| 452 | return clk->rate; |
| 453 | } |
| 454 | EXPORT_SYMBOL_GPL(clk_get_rate); |
| 455 | |
| 456 | int clk_set_rate(struct clk *clk, unsigned long rate) |
| 457 | { |
| 458 | return clk_set_rate_ex(clk, rate, 0); |
| 459 | } |
| 460 | EXPORT_SYMBOL_GPL(clk_set_rate); |
| 461 | |
| 462 | int clk_set_rate_ex(struct clk *clk, unsigned long rate, int algo_id) |
| 463 | { |
| 464 | int ret = -EOPNOTSUPP; |
| 465 | unsigned long flags; |
| 466 | |
| 467 | spin_lock_irqsave(&clock_lock, flags); |
| 468 | |
| 469 | if (likely(clk->ops && clk->ops->set_rate)) { |
| 470 | ret = clk->ops->set_rate(clk, rate, algo_id); |
| 471 | if (ret != 0) |
| 472 | goto out_unlock; |
| 473 | } else { |
| 474 | clk->rate = rate; |
| 475 | ret = 0; |
| 476 | } |
| 477 | |
| 478 | if (clk->ops && clk->ops->recalc) |
| 479 | clk->rate = clk->ops->recalc(clk); |
| 480 | |
| 481 | propagate_rate(clk); |
| 482 | |
| 483 | out_unlock: |
| 484 | spin_unlock_irqrestore(&clock_lock, flags); |
| 485 | |
| 486 | return ret; |
| 487 | } |
| 488 | EXPORT_SYMBOL_GPL(clk_set_rate_ex); |
| 489 | |
| 490 | int clk_set_parent(struct clk *clk, struct clk *parent) |
| 491 | { |
| 492 | unsigned long flags; |
| 493 | int ret = -EINVAL; |
| 494 | |
| 495 | if (!parent || !clk) |
| 496 | return ret; |
| 497 | if (clk->parent == parent) |
| 498 | return 0; |
| 499 | |
| 500 | spin_lock_irqsave(&clock_lock, flags); |
| 501 | if (clk->usecount == 0) { |
| 502 | if (clk->ops->set_parent) |
| 503 | ret = clk->ops->set_parent(clk, parent); |
| 504 | else |
| 505 | ret = clk_reparent(clk, parent); |
| 506 | |
| 507 | if (ret == 0) { |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 508 | if (clk->ops->recalc) |
| 509 | clk->rate = clk->ops->recalc(clk); |
Paul Mundt | 550a1ef | 2010-10-13 19:24:55 +0900 | [diff] [blame] | 510 | pr_debug("set parent of %p to %p (new rate %ld)\n", |
Magnus Damm | 6939539 | 2010-10-13 07:44:36 +0000 | [diff] [blame] | 511 | clk, clk->parent, clk->rate); |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 512 | propagate_rate(clk); |
| 513 | } |
| 514 | } else |
| 515 | ret = -EBUSY; |
| 516 | spin_unlock_irqrestore(&clock_lock, flags); |
| 517 | |
| 518 | return ret; |
| 519 | } |
| 520 | EXPORT_SYMBOL_GPL(clk_set_parent); |
| 521 | |
| 522 | struct clk *clk_get_parent(struct clk *clk) |
| 523 | { |
| 524 | return clk->parent; |
| 525 | } |
| 526 | EXPORT_SYMBOL_GPL(clk_get_parent); |
| 527 | |
| 528 | long clk_round_rate(struct clk *clk, unsigned long rate) |
| 529 | { |
| 530 | if (likely(clk->ops && clk->ops->round_rate)) { |
| 531 | unsigned long flags, rounded; |
| 532 | |
| 533 | spin_lock_irqsave(&clock_lock, flags); |
| 534 | rounded = clk->ops->round_rate(clk, rate); |
| 535 | spin_unlock_irqrestore(&clock_lock, flags); |
| 536 | |
| 537 | return rounded; |
| 538 | } |
| 539 | |
| 540 | return clk_get_rate(clk); |
| 541 | } |
| 542 | EXPORT_SYMBOL_GPL(clk_round_rate); |
| 543 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 544 | long clk_round_parent(struct clk *clk, unsigned long target, |
| 545 | unsigned long *best_freq, unsigned long *parent_freq, |
| 546 | unsigned int div_min, unsigned int div_max) |
| 547 | { |
| 548 | struct cpufreq_frequency_table *freq, *best = NULL; |
| 549 | unsigned long error = ULONG_MAX, freq_high, freq_low, div; |
| 550 | struct clk *parent = clk_get_parent(clk); |
| 551 | |
| 552 | if (!parent) { |
| 553 | *parent_freq = 0; |
| 554 | *best_freq = clk_round_rate(clk, target); |
| 555 | return abs(target - *best_freq); |
| 556 | } |
| 557 | |
| 558 | for (freq = parent->freq_table; freq->frequency != CPUFREQ_TABLE_END; |
| 559 | freq++) { |
| 560 | if (freq->frequency == CPUFREQ_ENTRY_INVALID) |
| 561 | continue; |
| 562 | |
| 563 | if (unlikely(freq->frequency / target <= div_min - 1)) { |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 564 | unsigned long freq_max; |
| 565 | |
| 566 | freq_max = (freq->frequency + div_min / 2) / div_min; |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 567 | if (error > target - freq_max) { |
| 568 | error = target - freq_max; |
| 569 | best = freq; |
| 570 | if (best_freq) |
| 571 | *best_freq = freq_max; |
| 572 | } |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 573 | |
| 574 | pr_debug("too low freq %lu, error %lu\n", freq->frequency, |
| 575 | target - freq_max); |
| 576 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 577 | if (!error) |
| 578 | break; |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 579 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 580 | continue; |
| 581 | } |
| 582 | |
| 583 | if (unlikely(freq->frequency / target >= div_max)) { |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 584 | unsigned long freq_min; |
| 585 | |
| 586 | freq_min = (freq->frequency + div_max / 2) / div_max; |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 587 | if (error > freq_min - target) { |
| 588 | error = freq_min - target; |
| 589 | best = freq; |
| 590 | if (best_freq) |
| 591 | *best_freq = freq_min; |
| 592 | } |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 593 | |
| 594 | pr_debug("too high freq %lu, error %lu\n", freq->frequency, |
| 595 | freq_min - target); |
| 596 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 597 | if (!error) |
| 598 | break; |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 599 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 600 | continue; |
| 601 | } |
| 602 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 603 | div = freq->frequency / target; |
| 604 | freq_high = freq->frequency / div; |
| 605 | freq_low = freq->frequency / (div + 1); |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 606 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 607 | if (freq_high - target < error) { |
| 608 | error = freq_high - target; |
| 609 | best = freq; |
| 610 | if (best_freq) |
| 611 | *best_freq = freq_high; |
| 612 | } |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 613 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 614 | if (target - freq_low < error) { |
| 615 | error = target - freq_low; |
| 616 | best = freq; |
| 617 | if (best_freq) |
| 618 | *best_freq = freq_low; |
| 619 | } |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 620 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 621 | pr_debug("%u / %lu = %lu, / %lu = %lu, best %lu, parent %u\n", |
| 622 | freq->frequency, div, freq_high, div + 1, freq_low, |
| 623 | *best_freq, best->frequency); |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 624 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 625 | if (!error) |
| 626 | break; |
| 627 | } |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 628 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 629 | if (parent_freq) |
| 630 | *parent_freq = best->frequency; |
Paul Mundt | a766b29 | 2010-11-08 09:40:23 +0900 | [diff] [blame^] | 631 | |
Guennadi Liakhovetski | 6af26c6 | 2010-11-02 11:27:24 +0000 | [diff] [blame] | 632 | return error; |
| 633 | } |
| 634 | EXPORT_SYMBOL_GPL(clk_round_parent); |
| 635 | |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 636 | #ifdef CONFIG_PM |
| 637 | static int clks_sysdev_suspend(struct sys_device *dev, pm_message_t state) |
| 638 | { |
| 639 | static pm_message_t prev_state; |
| 640 | struct clk *clkp; |
| 641 | |
| 642 | switch (state.event) { |
| 643 | case PM_EVENT_ON: |
| 644 | /* Resumeing from hibernation */ |
| 645 | if (prev_state.event != PM_EVENT_FREEZE) |
| 646 | break; |
| 647 | |
| 648 | list_for_each_entry(clkp, &clock_list, node) { |
| 649 | if (likely(clkp->ops)) { |
| 650 | unsigned long rate = clkp->rate; |
| 651 | |
| 652 | if (likely(clkp->ops->set_parent)) |
| 653 | clkp->ops->set_parent(clkp, |
| 654 | clkp->parent); |
| 655 | if (likely(clkp->ops->set_rate)) |
| 656 | clkp->ops->set_rate(clkp, |
| 657 | rate, NO_CHANGE); |
| 658 | else if (likely(clkp->ops->recalc)) |
| 659 | clkp->rate = clkp->ops->recalc(clkp); |
| 660 | } |
| 661 | } |
| 662 | break; |
| 663 | case PM_EVENT_FREEZE: |
| 664 | break; |
| 665 | case PM_EVENT_SUSPEND: |
| 666 | break; |
| 667 | } |
| 668 | |
| 669 | prev_state = state; |
| 670 | return 0; |
| 671 | } |
| 672 | |
| 673 | static int clks_sysdev_resume(struct sys_device *dev) |
| 674 | { |
| 675 | return clks_sysdev_suspend(dev, PMSG_ON); |
| 676 | } |
| 677 | |
| 678 | static struct sysdev_class clks_sysdev_class = { |
| 679 | .name = "clks", |
| 680 | }; |
| 681 | |
| 682 | static struct sysdev_driver clks_sysdev_driver = { |
| 683 | .suspend = clks_sysdev_suspend, |
| 684 | .resume = clks_sysdev_resume, |
| 685 | }; |
| 686 | |
| 687 | static struct sys_device clks_sysdev_dev = { |
| 688 | .cls = &clks_sysdev_class, |
| 689 | }; |
| 690 | |
| 691 | static int __init clk_sysdev_init(void) |
| 692 | { |
| 693 | sysdev_class_register(&clks_sysdev_class); |
| 694 | sysdev_driver_register(&clks_sysdev_class, &clks_sysdev_driver); |
| 695 | sysdev_register(&clks_sysdev_dev); |
| 696 | |
| 697 | return 0; |
| 698 | } |
| 699 | subsys_initcall(clk_sysdev_init); |
| 700 | #endif |
| 701 | |
| 702 | /* |
| 703 | * debugfs support to trace clock tree hierarchy and attributes |
| 704 | */ |
| 705 | static struct dentry *clk_debugfs_root; |
| 706 | |
| 707 | static int clk_debugfs_register_one(struct clk *c) |
| 708 | { |
| 709 | int err; |
| 710 | struct dentry *d, *child, *child_tmp; |
| 711 | struct clk *pa = c->parent; |
| 712 | char s[255]; |
| 713 | char *p = s; |
| 714 | |
Magnus Damm | 6939539 | 2010-10-13 07:44:36 +0000 | [diff] [blame] | 715 | p += sprintf(p, "%p", c); |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 716 | d = debugfs_create_dir(s, pa ? pa->dentry : clk_debugfs_root); |
| 717 | if (!d) |
| 718 | return -ENOMEM; |
| 719 | c->dentry = d; |
| 720 | |
| 721 | d = debugfs_create_u8("usecount", S_IRUGO, c->dentry, (u8 *)&c->usecount); |
| 722 | if (!d) { |
| 723 | err = -ENOMEM; |
| 724 | goto err_out; |
| 725 | } |
| 726 | d = debugfs_create_u32("rate", S_IRUGO, c->dentry, (u32 *)&c->rate); |
| 727 | if (!d) { |
| 728 | err = -ENOMEM; |
| 729 | goto err_out; |
| 730 | } |
| 731 | d = debugfs_create_x32("flags", S_IRUGO, c->dentry, (u32 *)&c->flags); |
| 732 | if (!d) { |
| 733 | err = -ENOMEM; |
| 734 | goto err_out; |
| 735 | } |
| 736 | return 0; |
| 737 | |
| 738 | err_out: |
| 739 | d = c->dentry; |
| 740 | list_for_each_entry_safe(child, child_tmp, &d->d_subdirs, d_u.d_child) |
| 741 | debugfs_remove(child); |
| 742 | debugfs_remove(c->dentry); |
| 743 | return err; |
| 744 | } |
| 745 | |
| 746 | static int clk_debugfs_register(struct clk *c) |
| 747 | { |
| 748 | int err; |
| 749 | struct clk *pa = c->parent; |
| 750 | |
| 751 | if (pa && !pa->dentry) { |
| 752 | err = clk_debugfs_register(pa); |
| 753 | if (err) |
| 754 | return err; |
| 755 | } |
| 756 | |
Magnus Damm | 6939539 | 2010-10-13 07:44:36 +0000 | [diff] [blame] | 757 | if (!c->dentry) { |
Magnus Damm | 8b5ee11 | 2010-05-11 13:29:25 +0000 | [diff] [blame] | 758 | err = clk_debugfs_register_one(c); |
| 759 | if (err) |
| 760 | return err; |
| 761 | } |
| 762 | return 0; |
| 763 | } |
| 764 | |
| 765 | static int __init clk_debugfs_init(void) |
| 766 | { |
| 767 | struct clk *c; |
| 768 | struct dentry *d; |
| 769 | int err; |
| 770 | |
| 771 | d = debugfs_create_dir("clock", NULL); |
| 772 | if (!d) |
| 773 | return -ENOMEM; |
| 774 | clk_debugfs_root = d; |
| 775 | |
| 776 | list_for_each_entry(c, &clock_list, node) { |
| 777 | err = clk_debugfs_register(c); |
| 778 | if (err) |
| 779 | goto err_out; |
| 780 | } |
| 781 | return 0; |
| 782 | err_out: |
| 783 | debugfs_remove_recursive(clk_debugfs_root); |
| 784 | return err; |
| 785 | } |
| 786 | late_initcall(clk_debugfs_init); |