1 /* 2 * OMAP clkctrl clock support 3 * 4 * Copyright (C) 2017 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-provider.h> 19 #include <linux/slab.h> 20 #include <linux/of.h> 21 #include <linux/of_address.h> 22 #include <linux/clk/ti.h> 23 #include <linux/delay.h> 24 #include <linux/timekeeping.h> 25 #include "clock.h" 26 27 #define NO_IDLEST 0 28 29 #define OMAP4_MODULEMODE_MASK 0x3 30 31 #define MODULEMODE_HWCTRL 0x1 32 #define MODULEMODE_SWCTRL 0x2 33 34 #define OMAP4_IDLEST_MASK (0x3 << 16) 35 #define OMAP4_IDLEST_SHIFT 16 36 37 #define OMAP4_STBYST_MASK BIT(18) 38 #define OMAP4_STBYST_SHIFT 18 39 40 #define CLKCTRL_IDLEST_FUNCTIONAL 0x0 41 #define CLKCTRL_IDLEST_INTERFACE_IDLE 0x2 42 #define CLKCTRL_IDLEST_DISABLED 0x3 43 44 /* These timeouts are in us */ 45 #define OMAP4_MAX_MODULE_READY_TIME 2000 46 #define OMAP4_MAX_MODULE_DISABLE_TIME 5000 47 48 static bool _early_timeout = true; 49 50 struct omap_clkctrl_provider { 51 void __iomem *base; 52 struct list_head clocks; 53 char *clkdm_name; 54 }; 55 56 struct omap_clkctrl_clk { 57 struct clk_hw *clk; 58 u16 reg_offset; 59 int bit_offset; 60 struct list_head node; 61 }; 62 63 union omap4_timeout { 64 u32 cycles; 65 ktime_t start; 66 }; 67 68 static const struct omap_clkctrl_data default_clkctrl_data[] __initconst = { 69 { 0 }, 70 }; 71 72 static u32 _omap4_idlest(u32 val) 73 { 74 val &= OMAP4_IDLEST_MASK; 75 val >>= OMAP4_IDLEST_SHIFT; 76 77 return val; 78 } 79 80 static bool _omap4_is_idle(u32 val) 81 { 82 val = _omap4_idlest(val); 83 84 return val == CLKCTRL_IDLEST_DISABLED; 85 } 86 87 static bool _omap4_is_ready(u32 val) 88 { 89 val = _omap4_idlest(val); 90 91 return val == CLKCTRL_IDLEST_FUNCTIONAL || 92 val == CLKCTRL_IDLEST_INTERFACE_IDLE; 93 } 94 95 static bool _omap4_is_timeout(union omap4_timeout *time, u32 timeout) 96 { 97 /* 98 * There are two special cases where ktime_to_ns() can't be 99 * used to track the timeouts. First one is during early boot 100 * when the timers haven't been initialized yet. The second 101 * one is during suspend-resume cycle while timekeeping is 102 * being suspended / resumed. Clocksource for the system 103 * can be from a timer that requires pm_runtime access, which 104 * will eventually bring us here with timekeeping_suspended, 105 * during both suspend entry and resume paths. This happens 106 * at least on am43xx platform. Account for flakeyness 107 * with udelay() by multiplying the timeout value by 2. 108 */ 109 if (unlikely(_early_timeout || timekeeping_suspended)) { 110 if (time->cycles++ < timeout) { 111 udelay(1 * 2); 112 return false; 113 } 114 } else { 115 if (!ktime_to_ns(time->start)) { 116 time->start = ktime_get(); 117 return false; 118 } 119 120 if (ktime_us_delta(ktime_get(), time->start) < timeout) { 121 cpu_relax(); 122 return false; 123 } 124 } 125 126 return true; 127 } 128 129 static int __init _omap4_disable_early_timeout(void) 130 { 131 _early_timeout = false; 132 133 return 0; 134 } 135 arch_initcall(_omap4_disable_early_timeout); 136 137 static int _omap4_clkctrl_clk_enable(struct clk_hw *hw) 138 { 139 struct clk_hw_omap *clk = to_clk_hw_omap(hw); 140 u32 val; 141 int ret; 142 union omap4_timeout timeout = { 0 }; 143 144 if (clk->clkdm) { 145 ret = ti_clk_ll_ops->clkdm_clk_enable(clk->clkdm, hw->clk); 146 if (ret) { 147 WARN(1, 148 "%s: could not enable %s's clockdomain %s: %d\n", 149 __func__, clk_hw_get_name(hw), 150 clk->clkdm_name, ret); 151 return ret; 152 } 153 } 154 155 if (!clk->enable_bit) 156 return 0; 157 158 val = ti_clk_ll_ops->clk_readl(&clk->enable_reg); 159 160 val &= ~OMAP4_MODULEMODE_MASK; 161 val |= clk->enable_bit; 162 163 ti_clk_ll_ops->clk_writel(val, &clk->enable_reg); 164 165 if (test_bit(NO_IDLEST, &clk->flags)) 166 return 0; 167 168 /* Wait until module is enabled */ 169 while (!_omap4_is_ready(ti_clk_ll_ops->clk_readl(&clk->enable_reg))) { 170 if (_omap4_is_timeout(&timeout, OMAP4_MAX_MODULE_READY_TIME)) { 171 pr_err("%s: failed to enable\n", clk_hw_get_name(hw)); 172 return -EBUSY; 173 } 174 } 175 176 return 0; 177 } 178 179 static void _omap4_clkctrl_clk_disable(struct clk_hw *hw) 180 { 181 struct clk_hw_omap *clk = to_clk_hw_omap(hw); 182 u32 val; 183 union omap4_timeout timeout = { 0 }; 184 185 if (!clk->enable_bit) 186 goto exit; 187 188 val = ti_clk_ll_ops->clk_readl(&clk->enable_reg); 189 190 val &= ~OMAP4_MODULEMODE_MASK; 191 192 ti_clk_ll_ops->clk_writel(val, &clk->enable_reg); 193 194 if (test_bit(NO_IDLEST, &clk->flags)) 195 goto exit; 196 197 /* Wait until module is disabled */ 198 while (!_omap4_is_idle(ti_clk_ll_ops->clk_readl(&clk->enable_reg))) { 199 if (_omap4_is_timeout(&timeout, 200 OMAP4_MAX_MODULE_DISABLE_TIME)) { 201 pr_err("%s: failed to disable\n", clk_hw_get_name(hw)); 202 break; 203 } 204 } 205 206 exit: 207 if (clk->clkdm) 208 ti_clk_ll_ops->clkdm_clk_disable(clk->clkdm, hw->clk); 209 } 210 211 static int _omap4_clkctrl_clk_is_enabled(struct clk_hw *hw) 212 { 213 struct clk_hw_omap *clk = to_clk_hw_omap(hw); 214 u32 val; 215 216 val = ti_clk_ll_ops->clk_readl(&clk->enable_reg); 217 218 if (val & clk->enable_bit) 219 return 1; 220 221 return 0; 222 } 223 224 static const struct clk_ops omap4_clkctrl_clk_ops = { 225 .enable = _omap4_clkctrl_clk_enable, 226 .disable = _omap4_clkctrl_clk_disable, 227 .is_enabled = _omap4_clkctrl_clk_is_enabled, 228 .init = omap2_init_clk_clkdm, 229 }; 230 231 static struct clk_hw *_ti_omap4_clkctrl_xlate(struct of_phandle_args *clkspec, 232 void *data) 233 { 234 struct omap_clkctrl_provider *provider = data; 235 struct omap_clkctrl_clk *entry; 236 bool found = false; 237 238 if (clkspec->args_count != 2) 239 return ERR_PTR(-EINVAL); 240 241 pr_debug("%s: looking for %x:%x\n", __func__, 242 clkspec->args[0], clkspec->args[1]); 243 244 list_for_each_entry(entry, &provider->clocks, node) { 245 if (entry->reg_offset == clkspec->args[0] && 246 entry->bit_offset == clkspec->args[1]) { 247 found = true; 248 break; 249 } 250 } 251 252 if (!found) 253 return ERR_PTR(-EINVAL); 254 255 return entry->clk; 256 } 257 258 /* Get clkctrl clock base name based on clkctrl_name or dts node */ 259 static const char * __init clkctrl_get_clock_name(struct device_node *np, 260 const char *clkctrl_name, 261 int offset, int index, 262 bool legacy_naming) 263 { 264 char *clock_name; 265 266 /* l4per-clkctrl:1234:0 style naming based on clkctrl_name */ 267 if (clkctrl_name && !legacy_naming) { 268 clock_name = kasprintf(GFP_KERNEL, "%s-clkctrl:%04x:%d", 269 clkctrl_name, offset, index); 270 strreplace(clock_name, '_', '-'); 271 272 return clock_name; 273 } 274 275 /* l4per:1234:0 old style naming based on clkctrl_name */ 276 if (clkctrl_name) 277 return kasprintf(GFP_KERNEL, "%s_cm:clk:%04x:%d", 278 clkctrl_name, offset, index); 279 280 /* l4per_cm:1234:0 old style naming based on parent node name */ 281 if (legacy_naming) 282 return kasprintf(GFP_KERNEL, "%pOFn:clk:%04x:%d", 283 np->parent, offset, index); 284 285 /* l4per-clkctrl:1234:0 style naming based on node name */ 286 return kasprintf(GFP_KERNEL, "%pOFn:%04x:%d", np, offset, index); 287 } 288 289 static int __init 290 _ti_clkctrl_clk_register(struct omap_clkctrl_provider *provider, 291 struct device_node *node, struct clk_hw *clk_hw, 292 u16 offset, u8 bit, const char * const *parents, 293 int num_parents, const struct clk_ops *ops, 294 const char *clkctrl_name) 295 { 296 struct clk_init_data init = { NULL }; 297 struct clk *clk; 298 struct omap_clkctrl_clk *clkctrl_clk; 299 int ret = 0; 300 301 init.name = clkctrl_get_clock_name(node, clkctrl_name, offset, bit, 302 ti_clk_get_features()->flags & 303 TI_CLK_CLKCTRL_COMPAT); 304 305 clkctrl_clk = kzalloc(sizeof(*clkctrl_clk), GFP_KERNEL); 306 if (!init.name || !clkctrl_clk) { 307 ret = -ENOMEM; 308 goto cleanup; 309 } 310 311 clk_hw->init = &init; 312 init.parent_names = parents; 313 init.num_parents = num_parents; 314 init.ops = ops; 315 init.flags = 0; 316 317 clk = ti_clk_register(NULL, clk_hw, init.name); 318 if (IS_ERR_OR_NULL(clk)) { 319 ret = -EINVAL; 320 goto cleanup; 321 } 322 323 clkctrl_clk->reg_offset = offset; 324 clkctrl_clk->bit_offset = bit; 325 clkctrl_clk->clk = clk_hw; 326 327 list_add(&clkctrl_clk->node, &provider->clocks); 328 329 return 0; 330 331 cleanup: 332 kfree(init.name); 333 kfree(clkctrl_clk); 334 return ret; 335 } 336 337 static void __init 338 _ti_clkctrl_setup_gate(struct omap_clkctrl_provider *provider, 339 struct device_node *node, u16 offset, 340 const struct omap_clkctrl_bit_data *data, 341 void __iomem *reg, const char *clkctrl_name) 342 { 343 struct clk_hw_omap *clk_hw; 344 345 clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL); 346 if (!clk_hw) 347 return; 348 349 clk_hw->enable_bit = data->bit; 350 clk_hw->enable_reg.ptr = reg; 351 352 if (_ti_clkctrl_clk_register(provider, node, &clk_hw->hw, offset, 353 data->bit, data->parents, 1, 354 &omap_gate_clk_ops, clkctrl_name)) 355 kfree(clk_hw); 356 } 357 358 static void __init 359 _ti_clkctrl_setup_mux(struct omap_clkctrl_provider *provider, 360 struct device_node *node, u16 offset, 361 const struct omap_clkctrl_bit_data *data, 362 void __iomem *reg, const char *clkctrl_name) 363 { 364 struct clk_omap_mux *mux; 365 int num_parents = 0; 366 const char * const *pname; 367 368 mux = kzalloc(sizeof(*mux), GFP_KERNEL); 369 if (!mux) 370 return; 371 372 pname = data->parents; 373 while (*pname) { 374 num_parents++; 375 pname++; 376 } 377 378 mux->mask = num_parents; 379 if (!(mux->flags & CLK_MUX_INDEX_ONE)) 380 mux->mask--; 381 382 mux->mask = (1 << fls(mux->mask)) - 1; 383 384 mux->shift = data->bit; 385 mux->reg.ptr = reg; 386 387 if (_ti_clkctrl_clk_register(provider, node, &mux->hw, offset, 388 data->bit, data->parents, num_parents, 389 &ti_clk_mux_ops, clkctrl_name)) 390 kfree(mux); 391 } 392 393 static void __init 394 _ti_clkctrl_setup_div(struct omap_clkctrl_provider *provider, 395 struct device_node *node, u16 offset, 396 const struct omap_clkctrl_bit_data *data, 397 void __iomem *reg, const char *clkctrl_name) 398 { 399 struct clk_omap_divider *div; 400 const struct omap_clkctrl_div_data *div_data = data->data; 401 u8 div_flags = 0; 402 403 div = kzalloc(sizeof(*div), GFP_KERNEL); 404 if (!div) 405 return; 406 407 div->reg.ptr = reg; 408 div->shift = data->bit; 409 div->flags = div_data->flags; 410 411 if (div->flags & CLK_DIVIDER_POWER_OF_TWO) 412 div_flags |= CLKF_INDEX_POWER_OF_TWO; 413 414 if (ti_clk_parse_divider_data((int *)div_data->dividers, 0, 415 div_data->max_div, div_flags, 416 div)) { 417 pr_err("%s: Data parsing for %pOF:%04x:%d failed\n", __func__, 418 node, offset, data->bit); 419 kfree(div); 420 return; 421 } 422 423 if (_ti_clkctrl_clk_register(provider, node, &div->hw, offset, 424 data->bit, data->parents, 1, 425 &ti_clk_divider_ops, clkctrl_name)) 426 kfree(div); 427 } 428 429 static void __init 430 _ti_clkctrl_setup_subclks(struct omap_clkctrl_provider *provider, 431 struct device_node *node, 432 const struct omap_clkctrl_reg_data *data, 433 void __iomem *reg, const char *clkctrl_name) 434 { 435 const struct omap_clkctrl_bit_data *bits = data->bit_data; 436 437 if (!bits) 438 return; 439 440 while (bits->bit) { 441 switch (bits->type) { 442 case TI_CLK_GATE: 443 _ti_clkctrl_setup_gate(provider, node, data->offset, 444 bits, reg, clkctrl_name); 445 break; 446 447 case TI_CLK_DIVIDER: 448 _ti_clkctrl_setup_div(provider, node, data->offset, 449 bits, reg, clkctrl_name); 450 break; 451 452 case TI_CLK_MUX: 453 _ti_clkctrl_setup_mux(provider, node, data->offset, 454 bits, reg, clkctrl_name); 455 break; 456 457 default: 458 pr_err("%s: bad subclk type: %d\n", __func__, 459 bits->type); 460 return; 461 } 462 bits++; 463 } 464 } 465 466 static void __init _clkctrl_add_provider(void *data, 467 struct device_node *np) 468 { 469 of_clk_add_hw_provider(np, _ti_omap4_clkctrl_xlate, data); 470 } 471 472 /* Get clock name based on compatible string for clkctrl */ 473 static char * __init clkctrl_get_name(struct device_node *np) 474 { 475 struct property *prop; 476 const int prefix_len = 11; 477 const char *compat; 478 char *name; 479 480 of_property_for_each_string(np, "compatible", prop, compat) { 481 if (!strncmp("ti,clkctrl-", compat, prefix_len)) { 482 /* Two letter minimum name length for l3, l4 etc */ 483 if (strnlen(compat + prefix_len, 16) < 2) 484 continue; 485 name = kasprintf(GFP_KERNEL, "%s", compat + prefix_len); 486 if (!name) 487 continue; 488 strreplace(name, '-', '_'); 489 490 return name; 491 } 492 } 493 494 return NULL; 495 } 496 497 static void __init _ti_omap4_clkctrl_setup(struct device_node *node) 498 { 499 struct omap_clkctrl_provider *provider; 500 const struct omap_clkctrl_data *data = default_clkctrl_data; 501 const struct omap_clkctrl_reg_data *reg_data; 502 struct clk_init_data init = { NULL }; 503 struct clk_hw_omap *hw; 504 struct clk *clk; 505 struct omap_clkctrl_clk *clkctrl_clk = NULL; 506 const __be32 *addrp; 507 bool legacy_naming; 508 char *clkctrl_name; 509 u32 addr; 510 int ret; 511 char *c; 512 u16 soc_mask = 0; 513 514 if (!(ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT) && 515 of_node_name_eq(node, "clk")) 516 ti_clk_features.flags |= TI_CLK_CLKCTRL_COMPAT; 517 518 addrp = of_get_address(node, 0, NULL, NULL); 519 addr = (u32)of_translate_address(node, addrp); 520 521 #ifdef CONFIG_ARCH_OMAP4 522 if (of_machine_is_compatible("ti,omap4")) 523 data = omap4_clkctrl_data; 524 #endif 525 #ifdef CONFIG_SOC_OMAP5 526 if (of_machine_is_compatible("ti,omap5")) 527 data = omap5_clkctrl_data; 528 #endif 529 #ifdef CONFIG_SOC_DRA7XX 530 if (of_machine_is_compatible("ti,dra7")) { 531 if (ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT) 532 data = dra7_clkctrl_compat_data; 533 else 534 data = dra7_clkctrl_data; 535 } 536 537 if (of_machine_is_compatible("ti,dra72")) 538 soc_mask = CLKF_SOC_DRA72; 539 if (of_machine_is_compatible("ti,dra74")) 540 soc_mask = CLKF_SOC_DRA74; 541 if (of_machine_is_compatible("ti,dra76")) 542 soc_mask = CLKF_SOC_DRA76; 543 #endif 544 #ifdef CONFIG_SOC_AM33XX 545 if (of_machine_is_compatible("ti,am33xx")) { 546 if (ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT) 547 data = am3_clkctrl_compat_data; 548 else 549 data = am3_clkctrl_data; 550 } 551 #endif 552 #ifdef CONFIG_SOC_AM43XX 553 if (of_machine_is_compatible("ti,am4372")) { 554 if (ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT) 555 data = am4_clkctrl_compat_data; 556 else 557 data = am4_clkctrl_data; 558 } 559 560 if (of_machine_is_compatible("ti,am438x")) { 561 if (ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT) 562 data = am438x_clkctrl_compat_data; 563 else 564 data = am438x_clkctrl_data; 565 } 566 #endif 567 #ifdef CONFIG_SOC_TI81XX 568 if (of_machine_is_compatible("ti,dm814")) 569 data = dm814_clkctrl_data; 570 571 if (of_machine_is_compatible("ti,dm816")) 572 data = dm816_clkctrl_data; 573 #endif 574 575 if (ti_clk_get_features()->flags & TI_CLK_DEVICE_TYPE_GP) 576 soc_mask |= CLKF_SOC_NONSEC; 577 578 while (data->addr) { 579 if (addr == data->addr) 580 break; 581 582 data++; 583 } 584 585 if (!data->addr) { 586 pr_err("%pOF not found from clkctrl data.\n", node); 587 return; 588 } 589 590 provider = kzalloc(sizeof(*provider), GFP_KERNEL); 591 if (!provider) 592 return; 593 594 provider->base = of_iomap(node, 0); 595 596 legacy_naming = ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT; 597 clkctrl_name = clkctrl_get_name(node); 598 if (clkctrl_name) { 599 provider->clkdm_name = kasprintf(GFP_KERNEL, 600 "%s_clkdm", clkctrl_name); 601 goto clkdm_found; 602 } 603 604 /* 605 * The code below can be removed when all clkctrl nodes use domain 606 * specific compatible proprerty and standard clock node naming 607 */ 608 if (legacy_naming) { 609 provider->clkdm_name = kasprintf(GFP_KERNEL, "%pOFnxxx", node->parent); 610 if (!provider->clkdm_name) { 611 kfree(provider); 612 return; 613 } 614 615 /* 616 * Create default clkdm name, replace _cm from end of parent 617 * node name with _clkdm 618 */ 619 provider->clkdm_name[strlen(provider->clkdm_name) - 2] = 0; 620 } else { 621 provider->clkdm_name = kasprintf(GFP_KERNEL, "%pOFn", node); 622 if (!provider->clkdm_name) { 623 kfree(provider); 624 return; 625 } 626 627 /* 628 * Create default clkdm name, replace _clkctrl from end of 629 * node name with _clkdm 630 */ 631 provider->clkdm_name[strlen(provider->clkdm_name) - 7] = 0; 632 } 633 634 strcat(provider->clkdm_name, "clkdm"); 635 636 /* Replace any dash from the clkdm name with underscore */ 637 c = provider->clkdm_name; 638 639 while (*c) { 640 if (*c == '-') 641 *c = '_'; 642 c++; 643 } 644 clkdm_found: 645 INIT_LIST_HEAD(&provider->clocks); 646 647 /* Generate clocks */ 648 reg_data = data->regs; 649 650 while (reg_data->parent) { 651 if ((reg_data->flags & CLKF_SOC_MASK) && 652 (reg_data->flags & soc_mask) == 0) { 653 reg_data++; 654 continue; 655 } 656 657 hw = kzalloc(sizeof(*hw), GFP_KERNEL); 658 if (!hw) 659 return; 660 661 hw->enable_reg.ptr = provider->base + reg_data->offset; 662 663 _ti_clkctrl_setup_subclks(provider, node, reg_data, 664 hw->enable_reg.ptr, clkctrl_name); 665 666 if (reg_data->flags & CLKF_SW_SUP) 667 hw->enable_bit = MODULEMODE_SWCTRL; 668 if (reg_data->flags & CLKF_HW_SUP) 669 hw->enable_bit = MODULEMODE_HWCTRL; 670 if (reg_data->flags & CLKF_NO_IDLEST) 671 set_bit(NO_IDLEST, &hw->flags); 672 673 if (reg_data->clkdm_name) 674 hw->clkdm_name = reg_data->clkdm_name; 675 else 676 hw->clkdm_name = provider->clkdm_name; 677 678 init.parent_names = ®_data->parent; 679 init.num_parents = 1; 680 init.flags = 0; 681 if (reg_data->flags & CLKF_SET_RATE_PARENT) 682 init.flags |= CLK_SET_RATE_PARENT; 683 684 init.name = clkctrl_get_clock_name(node, clkctrl_name, 685 reg_data->offset, 0, 686 legacy_naming); 687 if (!init.name) 688 goto cleanup; 689 690 clkctrl_clk = kzalloc(sizeof(*clkctrl_clk), GFP_KERNEL); 691 if (!clkctrl_clk) 692 goto cleanup; 693 694 init.ops = &omap4_clkctrl_clk_ops; 695 hw->hw.init = &init; 696 697 clk = ti_clk_register_omap_hw(NULL, &hw->hw, init.name); 698 if (IS_ERR_OR_NULL(clk)) 699 goto cleanup; 700 701 clkctrl_clk->reg_offset = reg_data->offset; 702 clkctrl_clk->clk = &hw->hw; 703 704 list_add(&clkctrl_clk->node, &provider->clocks); 705 706 reg_data++; 707 } 708 709 ret = of_clk_add_hw_provider(node, _ti_omap4_clkctrl_xlate, provider); 710 if (ret == -EPROBE_DEFER) 711 ti_clk_retry_init(node, provider, _clkctrl_add_provider); 712 713 kfree(clkctrl_name); 714 715 return; 716 717 cleanup: 718 kfree(hw); 719 kfree(init.name); 720 kfree(clkctrl_name); 721 kfree(clkctrl_clk); 722 } 723 CLK_OF_DECLARE(ti_omap4_clkctrl_clock, "ti,clkctrl", 724 _ti_omap4_clkctrl_setup); 725 726 /** 727 * ti_clk_is_in_standby - Check if clkctrl clock is in standby or not 728 * @clk: clock to check standby status for 729 * 730 * Finds whether the provided clock is in standby mode or not. Returns 731 * true if the provided clock is a clkctrl type clock and it is in standby, 732 * false otherwise. 733 */ 734 bool ti_clk_is_in_standby(struct clk *clk) 735 { 736 struct clk_hw *hw; 737 struct clk_hw_omap *hwclk; 738 u32 val; 739 740 hw = __clk_get_hw(clk); 741 742 if (!omap2_clk_is_hw_omap(hw)) 743 return false; 744 745 hwclk = to_clk_hw_omap(hw); 746 747 val = ti_clk_ll_ops->clk_readl(&hwclk->enable_reg); 748 749 if (val & OMAP4_STBYST_MASK) 750 return true; 751 752 return false; 753 } 754 EXPORT_SYMBOL_GPL(ti_clk_is_in_standby); 755