1/* 2 * OMAP2/3/4 clockdomain framework functions 3 * 4 * Copyright (C) 2008-2010 Texas Instruments, Inc. 5 * Copyright (C) 2008-2010 Nokia Corporation 6 * 7 * Written by Paul Walmsley and Jouni H��gander 8 * Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@ti.com> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 */ 14#undef DEBUG 15 16#include <linux/module.h> 17#include <linux/kernel.h> 18#include <linux/device.h> 19#include <linux/list.h> 20#include <linux/errno.h> 21#include <linux/delay.h> 22#include <linux/clk.h> 23#include <linux/limits.h> 24#include <linux/err.h> 25 26#include <linux/io.h> 27 28#include <linux/bitops.h> 29 30#include "prm.h" 31#include "prm-regbits-24xx.h" 32#include "cm.h" 33 34#include <plat/clock.h> 35#include <plat/powerdomain.h> 36#include <plat/clockdomain.h> 37#include <plat/prcm.h> 38 39/* clkdm_list contains all registered struct clockdomains */ 40static LIST_HEAD(clkdm_list); 41 42/* array of clockdomain deps to be added/removed when clkdm in hwsup mode */ 43static struct clkdm_autodep *autodeps; 44 45 46/* Private functions */ 47 48static struct clockdomain *_clkdm_lookup(const char *name) 49{ 50 struct clockdomain *clkdm, *temp_clkdm; 51 52 if (!name) 53 return NULL; 54 55 clkdm = NULL; 56 57 list_for_each_entry(temp_clkdm, &clkdm_list, node) { 58 if (!strcmp(name, temp_clkdm->name)) { 59 clkdm = temp_clkdm; 60 break; 61 } 62 } 63 64 return clkdm; 65} 66 67/** 68 * _clkdm_register - register a clockdomain 69 * @clkdm: struct clockdomain * to register 70 * 71 * Adds a clockdomain to the internal clockdomain list. 72 * Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is 73 * already registered by the provided name, or 0 upon success. 74 */ 75static int _clkdm_register(struct clockdomain *clkdm) 76{ 77 struct powerdomain *pwrdm; 78 79 if (!clkdm || !clkdm->name) 80 return -EINVAL; 81 82 if (!omap_chip_is(clkdm->omap_chip)) 83 return -EINVAL; 84 85 pwrdm = pwrdm_lookup(clkdm->pwrdm.name); 86 if (!pwrdm) { 87 pr_err("clockdomain: %s: powerdomain %s does not exist\n", 88 clkdm->name, clkdm->pwrdm.name); 89 return -EINVAL; 90 } 91 clkdm->pwrdm.ptr = pwrdm; 92 93 /* Verify that the clockdomain is not already registered */ 94 if (_clkdm_lookup(clkdm->name)) 95 return -EEXIST; 96 97 list_add(&clkdm->node, &clkdm_list); 98 99 pwrdm_add_clkdm(pwrdm, clkdm); 100 101 pr_debug("clockdomain: registered %s\n", clkdm->name); 102 103 return 0; 104} 105 106/* _clkdm_deps_lookup - look up the specified clockdomain in a clkdm list */ 107static struct clkdm_dep *_clkdm_deps_lookup(struct clockdomain *clkdm, 108 struct clkdm_dep *deps) 109{ 110 struct clkdm_dep *cd; 111 112 if (!clkdm || !deps || !omap_chip_is(clkdm->omap_chip)) 113 return ERR_PTR(-EINVAL); 114 115 for (cd = deps; cd->clkdm_name; cd++) { 116 if (!omap_chip_is(cd->omap_chip)) 117 continue; 118 119 if (!cd->clkdm && cd->clkdm_name) 120 cd->clkdm = _clkdm_lookup(cd->clkdm_name); 121 122 if (cd->clkdm == clkdm) 123 break; 124 } 125 126 if (!cd->clkdm_name) 127 return ERR_PTR(-ENOENT); 128 129 return cd; 130} 131 132/* 133 * _autodep_lookup - resolve autodep clkdm names to clkdm pointers; store 134 * @autodep: struct clkdm_autodep * to resolve 135 * 136 * Resolve autodep clockdomain names to clockdomain pointers via 137 * clkdm_lookup() and store the pointers in the autodep structure. An 138 * "autodep" is a clockdomain sleep/wakeup dependency that is 139 * automatically added and removed whenever clocks in the associated 140 * clockdomain are enabled or disabled (respectively) when the 141 * clockdomain is in hardware-supervised mode. Meant to be called 142 * once at clockdomain layer initialization, since these should remain 143 * fixed for a particular architecture. No return value. 144 */ 145static void _autodep_lookup(struct clkdm_autodep *autodep) 146{ 147 struct clockdomain *clkdm; 148 149 if (!autodep) 150 return; 151 152 if (!omap_chip_is(autodep->omap_chip)) 153 return; 154 155 clkdm = clkdm_lookup(autodep->clkdm.name); 156 if (!clkdm) { 157 pr_err("clockdomain: autodeps: clockdomain %s does not exist\n", 158 autodep->clkdm.name); 159 clkdm = ERR_PTR(-ENOENT); 160 } 161 autodep->clkdm.ptr = clkdm; 162} 163 164/* 165 * _clkdm_add_autodeps - add auto sleepdeps/wkdeps to clkdm upon clock enable 166 * @clkdm: struct clockdomain * 167 * 168 * Add the "autodep" sleep & wakeup dependencies to clockdomain 'clkdm' 169 * in hardware-supervised mode. Meant to be called from clock framework 170 * when a clock inside clockdomain 'clkdm' is enabled. No return value. 171 */ 172static void _clkdm_add_autodeps(struct clockdomain *clkdm) 173{ 174 struct clkdm_autodep *autodep; 175 176 if (!autodeps) 177 return; 178 179 for (autodep = autodeps; autodep->clkdm.ptr; autodep++) { 180 if (IS_ERR(autodep->clkdm.ptr)) 181 continue; 182 183 if (!omap_chip_is(autodep->omap_chip)) 184 continue; 185 186 pr_debug("clockdomain: adding %s sleepdep/wkdep for " 187 "clkdm %s\n", autodep->clkdm.ptr->name, 188 clkdm->name); 189 190 clkdm_add_sleepdep(clkdm, autodep->clkdm.ptr); 191 clkdm_add_wkdep(clkdm, autodep->clkdm.ptr); 192 } 193} 194 195/* 196 * _clkdm_add_autodeps - remove auto sleepdeps/wkdeps from clkdm 197 * @clkdm: struct clockdomain * 198 * 199 * Remove the "autodep" sleep & wakeup dependencies from clockdomain 'clkdm' 200 * in hardware-supervised mode. Meant to be called from clock framework 201 * when a clock inside clockdomain 'clkdm' is disabled. No return value. 202 */ 203static void _clkdm_del_autodeps(struct clockdomain *clkdm) 204{ 205 struct clkdm_autodep *autodep; 206 207 if (!autodeps) 208 return; 209 210 for (autodep = autodeps; autodep->clkdm.ptr; autodep++) { 211 if (IS_ERR(autodep->clkdm.ptr)) 212 continue; 213 214 if (!omap_chip_is(autodep->omap_chip)) 215 continue; 216 217 pr_debug("clockdomain: removing %s sleepdep/wkdep for " 218 "clkdm %s\n", autodep->clkdm.ptr->name, 219 clkdm->name); 220 221 clkdm_del_sleepdep(clkdm, autodep->clkdm.ptr); 222 clkdm_del_wkdep(clkdm, autodep->clkdm.ptr); 223 } 224} 225 226/* 227 * _omap2_clkdm_set_hwsup - set the hwsup idle transition bit 228 * @clkdm: struct clockdomain * 229 * @enable: int 0 to disable, 1 to enable 230 * 231 * Internal helper for actually switching the bit that controls hwsup 232 * idle transitions for clkdm. 233 */ 234static void _omap2_clkdm_set_hwsup(struct clockdomain *clkdm, int enable) 235{ 236 u32 bits, v; 237 238 if (cpu_is_omap24xx()) { 239 if (enable) 240 bits = OMAP24XX_CLKSTCTRL_ENABLE_AUTO; 241 else 242 bits = OMAP24XX_CLKSTCTRL_DISABLE_AUTO; 243 } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) { 244 if (enable) 245 bits = OMAP34XX_CLKSTCTRL_ENABLE_AUTO; 246 else 247 bits = OMAP34XX_CLKSTCTRL_DISABLE_AUTO; 248 } else { 249 BUG(); 250 } 251 252 bits = bits << __ffs(clkdm->clktrctrl_mask); 253 254 v = __raw_readl(clkdm->clkstctrl_reg); 255 v &= ~(clkdm->clktrctrl_mask); 256 v |= bits; 257 __raw_writel(v, clkdm->clkstctrl_reg); 258 259} 260 261/** 262 * _init_wkdep_usecount - initialize wkdep usecounts to match hardware 263 * @clkdm: clockdomain to initialize wkdep usecounts 264 * 265 * Initialize the wakeup dependency usecount variables for clockdomain @clkdm. 266 * If a wakeup dependency is present in the hardware, the usecount will be 267 * set to 1; otherwise, it will be set to 0. Software should clear all 268 * software wakeup dependencies prior to calling this function if it wishes 269 * to ensure that all usecounts start at 0. No return value. 270 */ 271static void _init_wkdep_usecount(struct clockdomain *clkdm) 272{ 273 u32 v; 274 struct clkdm_dep *cd; 275 276 if (!clkdm->wkdep_srcs) 277 return; 278 279 for (cd = clkdm->wkdep_srcs; cd->clkdm_name; cd++) { 280 if (!omap_chip_is(cd->omap_chip)) 281 continue; 282 283 if (!cd->clkdm && cd->clkdm_name) 284 cd->clkdm = _clkdm_lookup(cd->clkdm_name); 285 286 if (!cd->clkdm) { 287 WARN(!cd->clkdm, "clockdomain: %s: wkdep clkdm %s not " 288 "found\n", clkdm->name, cd->clkdm_name); 289 continue; 290 } 291 292 v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs, 293 PM_WKDEP, 294 (1 << cd->clkdm->dep_bit)); 295 296 if (v) 297 pr_debug("clockdomain: %s: wakeup dependency already " 298 "set to wake up when %s wakes\n", 299 clkdm->name, cd->clkdm->name); 300 301 atomic_set(&cd->wkdep_usecount, (v) ? 1 : 0); 302 } 303} 304 305/** 306 * _init_sleepdep_usecount - initialize sleepdep usecounts to match hardware 307 * @clkdm: clockdomain to initialize sleepdep usecounts 308 * 309 * Initialize the sleep dependency usecount variables for clockdomain @clkdm. 310 * If a sleep dependency is present in the hardware, the usecount will be 311 * set to 1; otherwise, it will be set to 0. Software should clear all 312 * software sleep dependencies prior to calling this function if it wishes 313 * to ensure that all usecounts start at 0. No return value. 314 */ 315static void _init_sleepdep_usecount(struct clockdomain *clkdm) 316{ 317 u32 v; 318 struct clkdm_dep *cd; 319 320 if (!cpu_is_omap34xx()) 321 return; 322 323 if (!clkdm->sleepdep_srcs) 324 return; 325 326 for (cd = clkdm->sleepdep_srcs; cd->clkdm_name; cd++) { 327 if (!omap_chip_is(cd->omap_chip)) 328 continue; 329 330 if (!cd->clkdm && cd->clkdm_name) 331 cd->clkdm = _clkdm_lookup(cd->clkdm_name); 332 333 if (!cd->clkdm) { 334 WARN(!cd->clkdm, "clockdomain: %s: sleepdep clkdm %s " 335 "not found\n", clkdm->name, cd->clkdm_name); 336 continue; 337 } 338 339 v = prm_read_mod_bits_shift(clkdm->pwrdm.ptr->prcm_offs, 340 OMAP3430_CM_SLEEPDEP, 341 (1 << cd->clkdm->dep_bit)); 342 343 if (v) 344 pr_debug("clockdomain: %s: sleep dependency already " 345 "set to prevent from idling until %s " 346 "idles\n", clkdm->name, cd->clkdm->name); 347 348 atomic_set(&cd->sleepdep_usecount, (v) ? 1 : 0); 349 } 350}; 351 352/* Public functions */ 353 354/** 355 * clkdm_init - set up the clockdomain layer 356 * @clkdms: optional pointer to an array of clockdomains to register 357 * @init_autodeps: optional pointer to an array of autodeps to register 358 * 359 * Set up internal state. If a pointer to an array of clockdomains 360 * @clkdms was supplied, loop through the list of clockdomains, 361 * register all that are available on the current platform. Similarly, 362 * if a pointer to an array of clockdomain autodependencies 363 * @init_autodeps was provided, register those. No return value. 364 */ 365void clkdm_init(struct clockdomain **clkdms, 366 struct clkdm_autodep *init_autodeps) 367{ 368 struct clockdomain **c = NULL; 369 struct clockdomain *clkdm; 370 struct clkdm_autodep *autodep = NULL; 371 372 if (clkdms) 373 for (c = clkdms; *c; c++) 374 _clkdm_register(*c); 375 376 autodeps = init_autodeps; 377 if (autodeps) 378 for (autodep = autodeps; autodep->clkdm.ptr; autodep++) 379 _autodep_lookup(autodep); 380 381 /* 382 * Ensure that the *dep_usecount registers reflect the current 383 * state of the PRCM. 384 */ 385 list_for_each_entry(clkdm, &clkdm_list, node) { 386 _init_wkdep_usecount(clkdm); 387 _init_sleepdep_usecount(clkdm); 388 } 389} 390 391/** 392 * clkdm_lookup - look up a clockdomain by name, return a pointer 393 * @name: name of clockdomain 394 * 395 * Find a registered clockdomain by its name @name. Returns a pointer 396 * to the struct clockdomain if found, or NULL otherwise. 397 */ 398struct clockdomain *clkdm_lookup(const char *name) 399{ 400 struct clockdomain *clkdm, *temp_clkdm; 401 402 if (!name) 403 return NULL; 404 405 clkdm = NULL; 406 407 list_for_each_entry(temp_clkdm, &clkdm_list, node) { 408 if (!strcmp(name, temp_clkdm->name)) { 409 clkdm = temp_clkdm; 410 break; 411 } 412 } 413 414 return clkdm; 415} 416 417/** 418 * clkdm_for_each - call function on each registered clockdomain 419 * @fn: callback function * 420 * 421 * Call the supplied function @fn for each registered clockdomain. 422 * The callback function @fn can return anything but 0 to bail 423 * out early from the iterator. The callback function is called with 424 * the clkdm_mutex held, so no clockdomain structure manipulation 425 * functions should be called from the callback, although hardware 426 * clockdomain control functions are fine. Returns the last return 427 * value of the callback function, which should be 0 for success or 428 * anything else to indicate failure; or -EINVAL if the function pointer 429 * is null. 430 */ 431int clkdm_for_each(int (*fn)(struct clockdomain *clkdm, void *user), 432 void *user) 433{ 434 struct clockdomain *clkdm; 435 int ret = 0; 436 437 if (!fn) 438 return -EINVAL; 439 440 list_for_each_entry(clkdm, &clkdm_list, node) { 441 ret = (*fn)(clkdm, user); 442 if (ret) 443 break; 444 } 445 446 return ret; 447} 448 449 450/** 451 * clkdm_get_pwrdm - return a ptr to the pwrdm that this clkdm resides in 452 * @clkdm: struct clockdomain * 453 * 454 * Return a pointer to the struct powerdomain that the specified clockdomain 455 * @clkdm exists in, or returns NULL if @clkdm is NULL. 456 */ 457struct powerdomain *clkdm_get_pwrdm(struct clockdomain *clkdm) 458{ 459 if (!clkdm) 460 return NULL; 461 462 return clkdm->pwrdm.ptr; 463} 464 465 466/* Hardware clockdomain control */ 467 468/** 469 * clkdm_add_wkdep - add a wakeup dependency from clkdm2 to clkdm1 470 * @clkdm1: wake this struct clockdomain * up (dependent) 471 * @clkdm2: when this struct clockdomain * wakes up (source) 472 * 473 * When the clockdomain represented by @clkdm2 wakes up, wake up 474 * @clkdm1. Implemented in hardware on the OMAP, this feature is 475 * designed to reduce wakeup latency of the dependent clockdomain @clkdm1. 476 * Returns -EINVAL if presented with invalid clockdomain pointers, 477 * -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or 0 upon 478 * success. 479 */ 480int clkdm_add_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) 481{ 482 struct clkdm_dep *cd; 483 484 if (!clkdm1 || !clkdm2) 485 return -EINVAL; 486 487 cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); 488 if (IS_ERR(cd)) { 489 pr_debug("clockdomain: hardware cannot set/clear wake up of " 490 "%s when %s wakes up\n", clkdm1->name, clkdm2->name); 491 return PTR_ERR(cd); 492 } 493 494 if (atomic_inc_return(&cd->wkdep_usecount) == 1) { 495 pr_debug("clockdomain: hardware will wake up %s when %s wakes " 496 "up\n", clkdm1->name, clkdm2->name); 497 498 prm_set_mod_reg_bits((1 << clkdm2->dep_bit), 499 clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); 500 } 501 502 return 0; 503} 504 505/** 506 * clkdm_del_wkdep - remove a wakeup dependency from clkdm2 to clkdm1 507 * @clkdm1: wake this struct clockdomain * up (dependent) 508 * @clkdm2: when this struct clockdomain * wakes up (source) 509 * 510 * Remove a wakeup dependency causing @clkdm1 to wake up when @clkdm2 511 * wakes up. Returns -EINVAL if presented with invalid clockdomain 512 * pointers, -ENOENT if @clkdm2 cannot wake up clkdm1 in hardware, or 513 * 0 upon success. 514 */ 515int clkdm_del_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) 516{ 517 struct clkdm_dep *cd; 518 519 if (!clkdm1 || !clkdm2) 520 return -EINVAL; 521 522 cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); 523 if (IS_ERR(cd)) { 524 pr_debug("clockdomain: hardware cannot set/clear wake up of " 525 "%s when %s wakes up\n", clkdm1->name, clkdm2->name); 526 return PTR_ERR(cd); 527 } 528 529 if (atomic_dec_return(&cd->wkdep_usecount) == 0) { 530 pr_debug("clockdomain: hardware will no longer wake up %s " 531 "after %s wakes up\n", clkdm1->name, clkdm2->name); 532 533 prm_clear_mod_reg_bits((1 << clkdm2->dep_bit), 534 clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP); 535 } 536 537 return 0; 538} 539 540/** 541 * clkdm_read_wkdep - read wakeup dependency state from clkdm2 to clkdm1 542 * @clkdm1: wake this struct clockdomain * up (dependent) 543 * @clkdm2: when this struct clockdomain * wakes up (source) 544 * 545 * Return 1 if a hardware wakeup dependency exists wherein @clkdm1 will be 546 * awoken when @clkdm2 wakes up; 0 if dependency is not set; -EINVAL 547 * if either clockdomain pointer is invalid; or -ENOENT if the hardware 548 * is incapable. 549 * 550 * REVISIT: Currently this function only represents software-controllable 551 * wakeup dependencies. Wakeup dependencies fixed in hardware are not 552 * yet handled here. 553 */ 554int clkdm_read_wkdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) 555{ 556 struct clkdm_dep *cd; 557 558 if (!clkdm1 || !clkdm2) 559 return -EINVAL; 560 561 cd = _clkdm_deps_lookup(clkdm2, clkdm1->wkdep_srcs); 562 if (IS_ERR(cd)) { 563 pr_debug("clockdomain: hardware cannot set/clear wake up of " 564 "%s when %s wakes up\n", clkdm1->name, clkdm2->name); 565 return PTR_ERR(cd); 566 } 567 568 return prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs, PM_WKDEP, 569 (1 << clkdm2->dep_bit)); 570} 571 572/** 573 * clkdm_clear_all_wkdeps - remove all wakeup dependencies from target clkdm 574 * @clkdm: struct clockdomain * to remove all wakeup dependencies from 575 * 576 * Remove all inter-clockdomain wakeup dependencies that could cause 577 * @clkdm to wake. Intended to be used during boot to initialize the 578 * PRCM to a known state, after all clockdomains are put into swsup idle 579 * and woken up. Returns -EINVAL if @clkdm pointer is invalid, or 580 * 0 upon success. 581 */ 582int clkdm_clear_all_wkdeps(struct clockdomain *clkdm) 583{ 584 struct clkdm_dep *cd; 585 u32 mask = 0; 586 587 if (!clkdm) 588 return -EINVAL; 589 590 for (cd = clkdm->wkdep_srcs; cd && cd->clkdm_name; cd++) { 591 if (!omap_chip_is(cd->omap_chip)) 592 continue; 593 594 /* PRM accesses are slow, so minimize them */ 595 mask |= 1 << cd->clkdm->dep_bit; 596 atomic_set(&cd->wkdep_usecount, 0); 597 } 598 599 prm_clear_mod_reg_bits(mask, clkdm->pwrdm.ptr->prcm_offs, PM_WKDEP); 600 601 return 0; 602} 603 604/** 605 * clkdm_add_sleepdep - add a sleep dependency from clkdm2 to clkdm1 606 * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) 607 * @clkdm2: when this struct clockdomain * is active (source) 608 * 609 * Prevent @clkdm1 from automatically going inactive (and then to 610 * retention or off) if @clkdm2 is active. Returns -EINVAL if 611 * presented with invalid clockdomain pointers or called on a machine 612 * that does not support software-configurable hardware sleep 613 * dependencies, -ENOENT if the specified dependency cannot be set in 614 * hardware, or 0 upon success. 615 */ 616int clkdm_add_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) 617{ 618 struct clkdm_dep *cd; 619 620 if (!cpu_is_omap34xx()) 621 return -EINVAL; 622 623 if (!clkdm1 || !clkdm2) 624 return -EINVAL; 625 626 cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); 627 if (IS_ERR(cd)) { 628 pr_debug("clockdomain: hardware cannot set/clear sleep " 629 "dependency affecting %s from %s\n", clkdm1->name, 630 clkdm2->name); 631 return PTR_ERR(cd); 632 } 633 634 if (atomic_inc_return(&cd->sleepdep_usecount) == 1) { 635 pr_debug("clockdomain: will prevent %s from sleeping if %s " 636 "is active\n", clkdm1->name, clkdm2->name); 637 638 cm_set_mod_reg_bits((1 << clkdm2->dep_bit), 639 clkdm1->pwrdm.ptr->prcm_offs, 640 OMAP3430_CM_SLEEPDEP); 641 } 642 643 return 0; 644} 645 646/** 647 * clkdm_del_sleepdep - remove a sleep dependency from clkdm2 to clkdm1 648 * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) 649 * @clkdm2: when this struct clockdomain * is active (source) 650 * 651 * Allow @clkdm1 to automatically go inactive (and then to retention or 652 * off), independent of the activity state of @clkdm2. Returns -EINVAL 653 * if presented with invalid clockdomain pointers or called on a machine 654 * that does not support software-configurable hardware sleep dependencies, 655 * -ENOENT if the specified dependency cannot be cleared in hardware, or 656 * 0 upon success. 657 */ 658int clkdm_del_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) 659{ 660 struct clkdm_dep *cd; 661 662 if (!cpu_is_omap34xx()) 663 return -EINVAL; 664 665 if (!clkdm1 || !clkdm2) 666 return -EINVAL; 667 668 cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); 669 if (IS_ERR(cd)) { 670 pr_debug("clockdomain: hardware cannot set/clear sleep " 671 "dependency affecting %s from %s\n", clkdm1->name, 672 clkdm2->name); 673 return PTR_ERR(cd); 674 } 675 676 if (atomic_dec_return(&cd->sleepdep_usecount) == 0) { 677 pr_debug("clockdomain: will no longer prevent %s from " 678 "sleeping if %s is active\n", clkdm1->name, 679 clkdm2->name); 680 681 cm_clear_mod_reg_bits((1 << clkdm2->dep_bit), 682 clkdm1->pwrdm.ptr->prcm_offs, 683 OMAP3430_CM_SLEEPDEP); 684 } 685 686 return 0; 687} 688 689/** 690 * clkdm_read_sleepdep - read sleep dependency state from clkdm2 to clkdm1 691 * @clkdm1: prevent this struct clockdomain * from sleeping (dependent) 692 * @clkdm2: when this struct clockdomain * is active (source) 693 * 694 * Return 1 if a hardware sleep dependency exists wherein @clkdm1 will 695 * not be allowed to automatically go inactive if @clkdm2 is active; 696 * 0 if @clkdm1's automatic power state inactivity transition is independent 697 * of @clkdm2's; -EINVAL if either clockdomain pointer is invalid or called 698 * on a machine that does not support software-configurable hardware sleep 699 * dependencies; or -ENOENT if the hardware is incapable. 700 * 701 * REVISIT: Currently this function only represents software-controllable 702 * sleep dependencies. Sleep dependencies fixed in hardware are not 703 * yet handled here. 704 */ 705int clkdm_read_sleepdep(struct clockdomain *clkdm1, struct clockdomain *clkdm2) 706{ 707 struct clkdm_dep *cd; 708 709 if (!cpu_is_omap34xx()) 710 return -EINVAL; 711 712 if (!clkdm1 || !clkdm2) 713 return -EINVAL; 714 715 cd = _clkdm_deps_lookup(clkdm2, clkdm1->sleepdep_srcs); 716 if (IS_ERR(cd)) { 717 pr_debug("clockdomain: hardware cannot set/clear sleep " 718 "dependency affecting %s from %s\n", clkdm1->name, 719 clkdm2->name); 720 return PTR_ERR(cd); 721 } 722 723 return prm_read_mod_bits_shift(clkdm1->pwrdm.ptr->prcm_offs, 724 OMAP3430_CM_SLEEPDEP, 725 (1 << clkdm2->dep_bit)); 726} 727 728/** 729 * clkdm_clear_all_sleepdeps - remove all sleep dependencies from target clkdm 730 * @clkdm: struct clockdomain * to remove all sleep dependencies from 731 * 732 * Remove all inter-clockdomain sleep dependencies that could prevent 733 * @clkdm from idling. Intended to be used during boot to initialize the 734 * PRCM to a known state, after all clockdomains are put into swsup idle 735 * and woken up. Returns -EINVAL if @clkdm pointer is invalid, or 736 * 0 upon success. 737 */ 738int clkdm_clear_all_sleepdeps(struct clockdomain *clkdm) 739{ 740 struct clkdm_dep *cd; 741 u32 mask = 0; 742 743 if (!cpu_is_omap34xx()) 744 return -EINVAL; 745 746 if (!clkdm) 747 return -EINVAL; 748 749 for (cd = clkdm->sleepdep_srcs; cd && cd->clkdm_name; cd++) { 750 if (!omap_chip_is(cd->omap_chip)) 751 continue; 752 753 /* PRM accesses are slow, so minimize them */ 754 mask |= 1 << cd->clkdm->dep_bit; 755 atomic_set(&cd->sleepdep_usecount, 0); 756 } 757 758 prm_clear_mod_reg_bits(mask, clkdm->pwrdm.ptr->prcm_offs, 759 OMAP3430_CM_SLEEPDEP); 760 761 return 0; 762} 763 764/** 765 * omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode 766 * @clkdm: struct clkdm * of a clockdomain 767 * 768 * Return the clockdomain @clkdm current state transition mode from the 769 * corresponding domain CM_CLKSTCTRL register. Returns -EINVAL if @clkdm 770 * is NULL or the current mode upon success. 771 */ 772static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm) 773{ 774 u32 v; 775 776 if (!clkdm) 777 return -EINVAL; 778 779 v = __raw_readl(clkdm->clkstctrl_reg); 780 v &= clkdm->clktrctrl_mask; 781 v >>= __ffs(clkdm->clktrctrl_mask); 782 783 return v; 784} 785 786/** 787 * omap2_clkdm_sleep - force clockdomain sleep transition 788 * @clkdm: struct clockdomain * 789 * 790 * Instruct the CM to force a sleep transition on the specified 791 * clockdomain @clkdm. Returns -EINVAL if @clkdm is NULL or if 792 * clockdomain does not support software-initiated sleep; 0 upon 793 * success. 794 */ 795int omap2_clkdm_sleep(struct clockdomain *clkdm) 796{ 797 if (!clkdm) 798 return -EINVAL; 799 800 if (!(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) { 801 pr_debug("clockdomain: %s does not support forcing " 802 "sleep via software\n", clkdm->name); 803 return -EINVAL; 804 } 805 806 pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name); 807 808 if (cpu_is_omap24xx()) { 809 810 cm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK, 811 clkdm->pwrdm.ptr->prcm_offs, OMAP2_PM_PWSTCTRL); 812 813 } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) { 814 815 u32 bits = (OMAP34XX_CLKSTCTRL_FORCE_SLEEP << 816 __ffs(clkdm->clktrctrl_mask)); 817 818 u32 v = __raw_readl(clkdm->clkstctrl_reg); 819 v &= ~(clkdm->clktrctrl_mask); 820 v |= bits; 821 __raw_writel(v, clkdm->clkstctrl_reg); 822 823 } else { 824 BUG(); 825 }; 826 827 return 0; 828} 829 830/** 831 * omap2_clkdm_wakeup - force clockdomain wakeup transition 832 * @clkdm: struct clockdomain * 833 * 834 * Instruct the CM to force a wakeup transition on the specified 835 * clockdomain @clkdm. Returns -EINVAL if @clkdm is NULL or if the 836 * clockdomain does not support software-controlled wakeup; 0 upon 837 * success. 838 */ 839int omap2_clkdm_wakeup(struct clockdomain *clkdm) 840{ 841 if (!clkdm) 842 return -EINVAL; 843 844 if (!(clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)) { 845 pr_debug("clockdomain: %s does not support forcing " 846 "wakeup via software\n", clkdm->name); 847 return -EINVAL; 848 } 849 850 pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name); 851 852 if (cpu_is_omap24xx()) { 853 854 cm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK, 855 clkdm->pwrdm.ptr->prcm_offs, OMAP2_PM_PWSTCTRL); 856 857 } else if (cpu_is_omap34xx() || cpu_is_omap44xx()) { 858 859 u32 bits = (OMAP34XX_CLKSTCTRL_FORCE_WAKEUP << 860 __ffs(clkdm->clktrctrl_mask)); 861 862 u32 v = __raw_readl(clkdm->clkstctrl_reg); 863 v &= ~(clkdm->clktrctrl_mask); 864 v |= bits; 865 __raw_writel(v, clkdm->clkstctrl_reg); 866 867 } else { 868 BUG(); 869 }; 870 871 return 0; 872} 873 874/** 875 * omap2_clkdm_allow_idle - enable hwsup idle transitions for clkdm 876 * @clkdm: struct clockdomain * 877 * 878 * Allow the hardware to automatically switch the clockdomain @clkdm into 879 * active or idle states, as needed by downstream clocks. If the 880 * clockdomain has any downstream clocks enabled in the clock 881 * framework, wkdep/sleepdep autodependencies are added; this is so 882 * device drivers can read and write to the device. No return value. 883 */ 884void omap2_clkdm_allow_idle(struct clockdomain *clkdm) 885{ 886 if (!clkdm) 887 return; 888 889 if (!(clkdm->flags & CLKDM_CAN_ENABLE_AUTO)) { 890 pr_debug("clock: automatic idle transitions cannot be enabled " 891 "on clockdomain %s\n", clkdm->name); 892 return; 893 } 894 895 pr_debug("clockdomain: enabling automatic idle transitions for %s\n", 896 clkdm->name); 897 898 if (cpu_is_omap44xx()) { 899 WARN_ONCE(1, "clockdomain: OMAP4 wakeup/sleep dependency " 900 "support is not yet implemented\n"); 901 } else { 902 if (atomic_read(&clkdm->usecount) > 0) 903 _clkdm_add_autodeps(clkdm); 904 } 905 906 _omap2_clkdm_set_hwsup(clkdm, 1); 907 908 pwrdm_clkdm_state_switch(clkdm); 909} 910 911/** 912 * omap2_clkdm_deny_idle - disable hwsup idle transitions for clkdm 913 * @clkdm: struct clockdomain * 914 * 915 * Prevent the hardware from automatically switching the clockdomain 916 * @clkdm into inactive or idle states. If the clockdomain has 917 * downstream clocks enabled in the clock framework, wkdep/sleepdep 918 * autodependencies are removed. No return value. 919 */ 920void omap2_clkdm_deny_idle(struct clockdomain *clkdm) 921{ 922 if (!clkdm) 923 return; 924 925 if (!(clkdm->flags & CLKDM_CAN_DISABLE_AUTO)) { 926 pr_debug("clockdomain: automatic idle transitions cannot be " 927 "disabled on %s\n", clkdm->name); 928 return; 929 } 930 931 pr_debug("clockdomain: disabling automatic idle transitions for %s\n", 932 clkdm->name); 933 934 _omap2_clkdm_set_hwsup(clkdm, 0); 935 936 if (cpu_is_omap44xx()) { 937 WARN_ONCE(1, "clockdomain: OMAP4 wakeup/sleep dependency " 938 "support is not yet implemented\n"); 939 } else { 940 if (atomic_read(&clkdm->usecount) > 0) 941 _clkdm_del_autodeps(clkdm); 942 } 943} 944 945 946/* Clockdomain-to-clock framework interface code */ 947 948/** 949 * omap2_clkdm_clk_enable - add an enabled downstream clock to this clkdm 950 * @clkdm: struct clockdomain * 951 * @clk: struct clk * of the enabled downstream clock 952 * 953 * Increment the usecount of the clockdomain @clkdm and ensure that it 954 * is awake before @clk is enabled. Intended to be called by 955 * clk_enable() code. If the clockdomain is in software-supervised 956 * idle mode, force the clockdomain to wake. If the clockdomain is in 957 * hardware-supervised idle mode, add clkdm-pwrdm autodependencies, to 958 * ensure that devices in the clockdomain can be read from/written to 959 * by on-chip processors. Returns -EINVAL if passed null pointers; 960 * returns 0 upon success or if the clockdomain is in hwsup idle mode. 961 */ 962int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk) 963{ 964 int v; 965 966 967 if (!clkdm || !clk) 968 return -EINVAL; 969 970 if (atomic_inc_return(&clkdm->usecount) > 1) 971 return 0; 972 973 /* Clockdomain now has one enabled downstream clock */ 974 975 pr_debug("clockdomain: clkdm %s: clk %s now enabled\n", clkdm->name, 976 clk->name); 977 978 if (!clkdm->clkstctrl_reg) 979 return 0; 980 981 v = omap2_clkdm_clktrctrl_read(clkdm); 982 983 if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) || 984 (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) { 985 /* Disable HW transitions when we are changing deps */ 986 _omap2_clkdm_set_hwsup(clkdm, 0); 987 _clkdm_add_autodeps(clkdm); 988 _omap2_clkdm_set_hwsup(clkdm, 1); 989 } else { 990 omap2_clkdm_wakeup(clkdm); 991 } 992 993 pwrdm_wait_transition(clkdm->pwrdm.ptr); 994 pwrdm_clkdm_state_switch(clkdm); 995 996 return 0; 997} 998 999/** 1000 * omap2_clkdm_clk_disable - remove an enabled downstream clock from this clkdm 1001 * @clkdm: struct clockdomain * 1002 * @clk: struct clk * of the disabled downstream clock 1003 * 1004 * Decrement the usecount of this clockdomain @clkdm when @clk is 1005 * disabled. Intended to be called by clk_disable() code. If the 1006 * clockdomain usecount goes to 0, put the clockdomain to sleep 1007 * (software-supervised mode) or remove the clkdm autodependencies 1008 * (hardware-supervised mode). Returns -EINVAL if passed null 1009 * pointers; -ERANGE if the @clkdm usecount underflows and debugging 1010 * is enabled; or returns 0 upon success or if the clockdomain is in 1011 * hwsup idle mode. 1012 */ 1013int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk) 1014{ 1015 int v; 1016 1017 1018 if (!clkdm || !clk) 1019 return -EINVAL; 1020 1021#ifdef DEBUG 1022 if (atomic_read(&clkdm->usecount) == 0) { 1023 WARN_ON(1); /* underflow */ 1024 return -ERANGE; 1025 } 1026#endif 1027 1028 if (atomic_dec_return(&clkdm->usecount) > 0) 1029 return 0; 1030 1031 /* All downstream clocks of this clockdomain are now disabled */ 1032 1033 pr_debug("clockdomain: clkdm %s: clk %s now disabled\n", clkdm->name, 1034 clk->name); 1035 1036 if (!clkdm->clkstctrl_reg) 1037 return 0; 1038 1039 v = omap2_clkdm_clktrctrl_read(clkdm); 1040 1041 if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) || 1042 (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO)) { 1043 /* Disable HW transitions when we are changing deps */ 1044 _omap2_clkdm_set_hwsup(clkdm, 0); 1045 _clkdm_del_autodeps(clkdm); 1046 _omap2_clkdm_set_hwsup(clkdm, 1); 1047 } else { 1048 omap2_clkdm_sleep(clkdm); 1049 } 1050 1051 pwrdm_clkdm_state_switch(clkdm); 1052 1053 return 0; 1054} 1055