1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * OMAP4 CM instance functions 4 * 5 * Copyright (C) 2009 Nokia Corporation 6 * Copyright (C) 2008-2011 Texas Instruments, Inc. 7 * Paul Walmsley 8 * Rajendra Nayak <rnayak@ti.com> 9 * 10 * This is needed since CM instances can be in the PRM, PRCM_MPU, CM1, 11 * or CM2 hardware modules. For example, the EMU_CM CM instance is in 12 * the PRM hardware module. What a mess... 13 */ 14 15 #include <linux/kernel.h> 16 #include <linux/types.h> 17 #include <linux/errno.h> 18 #include <linux/err.h> 19 #include <linux/io.h> 20 21 #include "clockdomain.h" 22 #include "cm.h" 23 #include "cm1_44xx.h" 24 #include "cm2_44xx.h" 25 #include "cm44xx.h" 26 #include "cm-regbits-34xx.h" 27 #include "prcm44xx.h" 28 #include "prm44xx.h" 29 #include "prcm_mpu44xx.h" 30 #include "prcm-common.h" 31 32 #define OMAP4430_IDLEST_SHIFT 16 33 #define OMAP4430_IDLEST_MASK (0x3 << 16) 34 #define OMAP4430_CLKTRCTRL_SHIFT 0 35 #define OMAP4430_CLKTRCTRL_MASK (0x3 << 0) 36 #define OMAP4430_MODULEMODE_SHIFT 0 37 #define OMAP4430_MODULEMODE_MASK (0x3 << 0) 38 39 /* 40 * CLKCTRL_IDLEST_*: possible values for the CM_*_CLKCTRL.IDLEST bitfield: 41 * 42 * 0x0 func: Module is fully functional, including OCP 43 * 0x1 trans: Module is performing transition: wakeup, or sleep, or sleep 44 * abortion 45 * 0x2 idle: Module is in Idle mode (only OCP part). It is functional if 46 * using separate functional clock 47 * 0x3 disabled: Module is disabled and cannot be accessed 48 * 49 */ 50 #define CLKCTRL_IDLEST_FUNCTIONAL 0x0 51 #define CLKCTRL_IDLEST_INTRANSITION 0x1 52 #define CLKCTRL_IDLEST_INTERFACE_IDLE 0x2 53 #define CLKCTRL_IDLEST_DISABLED 0x3 54 55 static struct omap_domain_base _cm_bases[OMAP4_MAX_PRCM_PARTITIONS]; 56 57 /** 58 * omap_cm_base_init - Populates the cm partitions 59 * 60 * Populates the base addresses of the _cm_bases 61 * array used for read/write of cm module registers. 62 */ 63 static void omap_cm_base_init(void) 64 { 65 memcpy(&_cm_bases[OMAP4430_PRM_PARTITION], &prm_base, sizeof(prm_base)); 66 memcpy(&_cm_bases[OMAP4430_CM1_PARTITION], &cm_base, sizeof(cm_base)); 67 memcpy(&_cm_bases[OMAP4430_CM2_PARTITION], &cm2_base, sizeof(cm2_base)); 68 memcpy(&_cm_bases[OMAP4430_PRCM_MPU_PARTITION], &prcm_mpu_base, 69 sizeof(prcm_mpu_base)); 70 } 71 72 /* Private functions */ 73 74 static u32 omap4_cminst_read_inst_reg(u8 part, u16 inst, u16 idx); 75 76 /** 77 * _clkctrl_idlest - read a CM_*_CLKCTRL register; mask & shift IDLEST bitfield 78 * @part: PRCM partition ID that the CM_CLKCTRL register exists in 79 * @inst: CM instance register offset (*_INST macro) 80 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) 81 * 82 * Return the IDLEST bitfield of a CM_*_CLKCTRL register, shifted down to 83 * bit 0. 84 */ 85 static u32 _clkctrl_idlest(u8 part, u16 inst, u16 clkctrl_offs) 86 { 87 u32 v = omap4_cminst_read_inst_reg(part, inst, clkctrl_offs); 88 v &= OMAP4430_IDLEST_MASK; 89 v >>= OMAP4430_IDLEST_SHIFT; 90 return v; 91 } 92 93 /** 94 * _is_module_ready - can module registers be accessed without causing an abort? 95 * @part: PRCM partition ID that the CM_CLKCTRL register exists in 96 * @inst: CM instance register offset (*_INST macro) 97 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) 98 * 99 * Returns true if the module's CM_*_CLKCTRL.IDLEST bitfield is either 100 * *FUNCTIONAL or *INTERFACE_IDLE; false otherwise. 101 */ 102 static bool _is_module_ready(u8 part, u16 inst, u16 clkctrl_offs) 103 { 104 u32 v; 105 106 v = _clkctrl_idlest(part, inst, clkctrl_offs); 107 108 return (v == CLKCTRL_IDLEST_FUNCTIONAL || 109 v == CLKCTRL_IDLEST_INTERFACE_IDLE) ? true : false; 110 } 111 112 /* Read a register in a CM instance */ 113 static u32 omap4_cminst_read_inst_reg(u8 part, u16 inst, u16 idx) 114 { 115 BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS || 116 part == OMAP4430_INVALID_PRCM_PARTITION || 117 !_cm_bases[part].va); 118 return readl_relaxed(_cm_bases[part].va + inst + idx); 119 } 120 121 /* Write into a register in a CM instance */ 122 static void omap4_cminst_write_inst_reg(u32 val, u8 part, u16 inst, u16 idx) 123 { 124 BUG_ON(part >= OMAP4_MAX_PRCM_PARTITIONS || 125 part == OMAP4430_INVALID_PRCM_PARTITION || 126 !_cm_bases[part].va); 127 writel_relaxed(val, _cm_bases[part].va + inst + idx); 128 } 129 130 /* Read-modify-write a register in CM1. Caller must lock */ 131 static u32 omap4_cminst_rmw_inst_reg_bits(u32 mask, u32 bits, u8 part, u16 inst, 132 s16 idx) 133 { 134 u32 v; 135 136 v = omap4_cminst_read_inst_reg(part, inst, idx); 137 v &= ~mask; 138 v |= bits; 139 omap4_cminst_write_inst_reg(v, part, inst, idx); 140 141 return v; 142 } 143 144 static u32 omap4_cminst_set_inst_reg_bits(u32 bits, u8 part, u16 inst, s16 idx) 145 { 146 return omap4_cminst_rmw_inst_reg_bits(bits, bits, part, inst, idx); 147 } 148 149 static u32 omap4_cminst_clear_inst_reg_bits(u32 bits, u8 part, u16 inst, 150 s16 idx) 151 { 152 return omap4_cminst_rmw_inst_reg_bits(bits, 0x0, part, inst, idx); 153 } 154 155 static u32 omap4_cminst_read_inst_reg_bits(u8 part, u16 inst, s16 idx, u32 mask) 156 { 157 u32 v; 158 159 v = omap4_cminst_read_inst_reg(part, inst, idx); 160 v &= mask; 161 v >>= __ffs(mask); 162 163 return v; 164 } 165 166 /* 167 * 168 */ 169 170 /** 171 * _clktrctrl_write - write @c to a CM_CLKSTCTRL.CLKTRCTRL register bitfield 172 * @c: CLKTRCTRL register bitfield (LSB = bit 0, i.e., unshifted) 173 * @part: PRCM partition ID that the CM_CLKSTCTRL register exists in 174 * @inst: CM instance register offset (*_INST macro) 175 * @cdoffs: Clockdomain register offset (*_CDOFFS macro) 176 * 177 * @c must be the unshifted value for CLKTRCTRL - i.e., this function 178 * will handle the shift itself. 179 */ 180 static void _clktrctrl_write(u8 c, u8 part, u16 inst, u16 cdoffs) 181 { 182 u32 v; 183 184 v = omap4_cminst_read_inst_reg(part, inst, cdoffs + OMAP4_CM_CLKSTCTRL); 185 v &= ~OMAP4430_CLKTRCTRL_MASK; 186 v |= c << OMAP4430_CLKTRCTRL_SHIFT; 187 omap4_cminst_write_inst_reg(v, part, inst, cdoffs + OMAP4_CM_CLKSTCTRL); 188 } 189 190 /** 191 * omap4_cminst_is_clkdm_in_hwsup - is a clockdomain in hwsup idle mode? 192 * @part: PRCM partition ID that the CM_CLKSTCTRL register exists in 193 * @inst: CM instance register offset (*_INST macro) 194 * @cdoffs: Clockdomain register offset (*_CDOFFS macro) 195 * 196 * Returns true if the clockdomain referred to by (@part, @inst, @cdoffs) 197 * is in hardware-supervised idle mode, or 0 otherwise. 198 */ 199 static bool omap4_cminst_is_clkdm_in_hwsup(u8 part, u16 inst, u16 cdoffs) 200 { 201 u32 v; 202 203 v = omap4_cminst_read_inst_reg(part, inst, cdoffs + OMAP4_CM_CLKSTCTRL); 204 v &= OMAP4430_CLKTRCTRL_MASK; 205 v >>= OMAP4430_CLKTRCTRL_SHIFT; 206 207 return (v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ? true : false; 208 } 209 210 /** 211 * omap4_cminst_clkdm_enable_hwsup - put a clockdomain in hwsup-idle mode 212 * @part: PRCM partition ID that the clockdomain registers exist in 213 * @inst: CM instance register offset (*_INST macro) 214 * @cdoffs: Clockdomain register offset (*_CDOFFS macro) 215 * 216 * Put a clockdomain referred to by (@part, @inst, @cdoffs) into 217 * hardware-supervised idle mode. No return value. 218 */ 219 static void omap4_cminst_clkdm_enable_hwsup(u8 part, u16 inst, u16 cdoffs) 220 { 221 _clktrctrl_write(OMAP34XX_CLKSTCTRL_ENABLE_AUTO, part, inst, cdoffs); 222 } 223 224 /** 225 * omap4_cminst_clkdm_disable_hwsup - put a clockdomain in swsup-idle mode 226 * @part: PRCM partition ID that the clockdomain registers exist in 227 * @inst: CM instance register offset (*_INST macro) 228 * @cdoffs: Clockdomain register offset (*_CDOFFS macro) 229 * 230 * Put a clockdomain referred to by (@part, @inst, @cdoffs) into 231 * software-supervised idle mode, i.e., controlled manually by the 232 * Linux OMAP clockdomain code. No return value. 233 */ 234 static void omap4_cminst_clkdm_disable_hwsup(u8 part, u16 inst, u16 cdoffs) 235 { 236 _clktrctrl_write(OMAP34XX_CLKSTCTRL_DISABLE_AUTO, part, inst, cdoffs); 237 } 238 239 /** 240 * omap4_cminst_clkdm_force_sleep - try to take a clockdomain out of idle 241 * @part: PRCM partition ID that the clockdomain registers exist in 242 * @inst: CM instance register offset (*_INST macro) 243 * @cdoffs: Clockdomain register offset (*_CDOFFS macro) 244 * 245 * Take a clockdomain referred to by (@part, @inst, @cdoffs) out of idle, 246 * waking it up. No return value. 247 */ 248 static void omap4_cminst_clkdm_force_wakeup(u8 part, u16 inst, u16 cdoffs) 249 { 250 _clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_WAKEUP, part, inst, cdoffs); 251 } 252 253 /* 254 * 255 */ 256 257 static void omap4_cminst_clkdm_force_sleep(u8 part, u16 inst, u16 cdoffs) 258 { 259 _clktrctrl_write(OMAP34XX_CLKSTCTRL_FORCE_SLEEP, part, inst, cdoffs); 260 } 261 262 /** 263 * omap4_cminst_wait_module_ready - wait for a module to be in 'func' state 264 * @part: PRCM partition ID that the CM_CLKCTRL register exists in 265 * @inst: CM instance register offset (*_INST macro) 266 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) 267 * @bit_shift: bit shift for the register, ignored for OMAP4+ 268 * 269 * Wait for the module IDLEST to be functional. If the idle state is in any 270 * the non functional state (trans, idle or disabled), module and thus the 271 * sysconfig cannot be accessed and will probably lead to an "imprecise 272 * external abort" 273 */ 274 static int omap4_cminst_wait_module_ready(u8 part, s16 inst, u16 clkctrl_offs, 275 u8 bit_shift) 276 { 277 int i = 0; 278 279 omap_test_timeout(_is_module_ready(part, inst, clkctrl_offs), 280 MAX_MODULE_READY_TIME, i); 281 282 return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY; 283 } 284 285 /** 286 * omap4_cminst_wait_module_idle - wait for a module to be in 'disabled' 287 * state 288 * @part: PRCM partition ID that the CM_CLKCTRL register exists in 289 * @inst: CM instance register offset (*_INST macro) 290 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) 291 * @bit_shift: Bit shift for the register, ignored for OMAP4+ 292 * 293 * Wait for the module IDLEST to be disabled. Some PRCM transition, 294 * like reset assertion or parent clock de-activation must wait the 295 * module to be fully disabled. 296 */ 297 static int omap4_cminst_wait_module_idle(u8 part, s16 inst, u16 clkctrl_offs, 298 u8 bit_shift) 299 { 300 int i = 0; 301 302 omap_test_timeout((_clkctrl_idlest(part, inst, clkctrl_offs) == 303 CLKCTRL_IDLEST_DISABLED), 304 MAX_MODULE_DISABLE_TIME, i); 305 306 return (i < MAX_MODULE_DISABLE_TIME) ? 0 : -EBUSY; 307 } 308 309 /** 310 * omap4_cminst_module_enable - Enable the modulemode inside CLKCTRL 311 * @mode: Module mode (SW or HW) 312 * @part: PRCM partition ID that the CM_CLKCTRL register exists in 313 * @inst: CM instance register offset (*_INST macro) 314 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) 315 * 316 * No return value. 317 */ 318 static void omap4_cminst_module_enable(u8 mode, u8 part, u16 inst, 319 u16 clkctrl_offs) 320 { 321 u32 v; 322 323 v = omap4_cminst_read_inst_reg(part, inst, clkctrl_offs); 324 v &= ~OMAP4430_MODULEMODE_MASK; 325 v |= mode << OMAP4430_MODULEMODE_SHIFT; 326 omap4_cminst_write_inst_reg(v, part, inst, clkctrl_offs); 327 } 328 329 /** 330 * omap4_cminst_module_disable - Disable the module inside CLKCTRL 331 * @part: PRCM partition ID that the CM_CLKCTRL register exists in 332 * @inst: CM instance register offset (*_INST macro) 333 * @clkctrl_offs: Module clock control register offset (*_CLKCTRL macro) 334 * 335 * No return value. 336 */ 337 static void omap4_cminst_module_disable(u8 part, u16 inst, u16 clkctrl_offs) 338 { 339 u32 v; 340 341 v = omap4_cminst_read_inst_reg(part, inst, clkctrl_offs); 342 v &= ~OMAP4430_MODULEMODE_MASK; 343 omap4_cminst_write_inst_reg(v, part, inst, clkctrl_offs); 344 } 345 346 /* 347 * Clockdomain low-level functions 348 */ 349 350 static int omap4_clkdm_add_wkup_sleep_dep(struct clockdomain *clkdm1, 351 struct clockdomain *clkdm2) 352 { 353 omap4_cminst_set_inst_reg_bits((1 << clkdm2->dep_bit), 354 clkdm1->prcm_partition, 355 clkdm1->cm_inst, clkdm1->clkdm_offs + 356 OMAP4_CM_STATICDEP); 357 return 0; 358 } 359 360 static int omap4_clkdm_del_wkup_sleep_dep(struct clockdomain *clkdm1, 361 struct clockdomain *clkdm2) 362 { 363 omap4_cminst_clear_inst_reg_bits((1 << clkdm2->dep_bit), 364 clkdm1->prcm_partition, 365 clkdm1->cm_inst, clkdm1->clkdm_offs + 366 OMAP4_CM_STATICDEP); 367 return 0; 368 } 369 370 static int omap4_clkdm_read_wkup_sleep_dep(struct clockdomain *clkdm1, 371 struct clockdomain *clkdm2) 372 { 373 return omap4_cminst_read_inst_reg_bits(clkdm1->prcm_partition, 374 clkdm1->cm_inst, 375 clkdm1->clkdm_offs + 376 OMAP4_CM_STATICDEP, 377 (1 << clkdm2->dep_bit)); 378 } 379 380 static int omap4_clkdm_clear_all_wkup_sleep_deps(struct clockdomain *clkdm) 381 { 382 struct clkdm_dep *cd; 383 u32 mask = 0; 384 385 if (!clkdm->prcm_partition) 386 return 0; 387 388 for (cd = clkdm->wkdep_srcs; cd && cd->clkdm_name; cd++) { 389 if (!cd->clkdm) 390 continue; /* only happens if data is erroneous */ 391 392 mask |= 1 << cd->clkdm->dep_bit; 393 cd->wkdep_usecount = 0; 394 } 395 396 omap4_cminst_clear_inst_reg_bits(mask, clkdm->prcm_partition, 397 clkdm->cm_inst, clkdm->clkdm_offs + 398 OMAP4_CM_STATICDEP); 399 return 0; 400 } 401 402 static int omap4_clkdm_sleep(struct clockdomain *clkdm) 403 { 404 if (clkdm->flags & CLKDM_CAN_HWSUP) 405 omap4_cminst_clkdm_enable_hwsup(clkdm->prcm_partition, 406 clkdm->cm_inst, 407 clkdm->clkdm_offs); 408 else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP) 409 omap4_cminst_clkdm_force_sleep(clkdm->prcm_partition, 410 clkdm->cm_inst, 411 clkdm->clkdm_offs); 412 else 413 return -EINVAL; 414 415 return 0; 416 } 417 418 static int omap4_clkdm_wakeup(struct clockdomain *clkdm) 419 { 420 omap4_cminst_clkdm_force_wakeup(clkdm->prcm_partition, 421 clkdm->cm_inst, clkdm->clkdm_offs); 422 return 0; 423 } 424 425 static void omap4_clkdm_allow_idle(struct clockdomain *clkdm) 426 { 427 omap4_cminst_clkdm_enable_hwsup(clkdm->prcm_partition, 428 clkdm->cm_inst, clkdm->clkdm_offs); 429 } 430 431 static void omap4_clkdm_deny_idle(struct clockdomain *clkdm) 432 { 433 if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) 434 omap4_clkdm_wakeup(clkdm); 435 else 436 omap4_cminst_clkdm_disable_hwsup(clkdm->prcm_partition, 437 clkdm->cm_inst, 438 clkdm->clkdm_offs); 439 } 440 441 static int omap4_clkdm_clk_enable(struct clockdomain *clkdm) 442 { 443 if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP) 444 return omap4_clkdm_wakeup(clkdm); 445 446 return 0; 447 } 448 449 static int omap4_clkdm_clk_disable(struct clockdomain *clkdm) 450 { 451 bool hwsup = false; 452 453 if (!clkdm->prcm_partition) 454 return 0; 455 456 /* 457 * The CLKDM_MISSING_IDLE_REPORTING flag documentation has 458 * more details on the unpleasant problem this is working 459 * around 460 */ 461 if (clkdm->flags & CLKDM_MISSING_IDLE_REPORTING && 462 !(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) { 463 omap4_clkdm_allow_idle(clkdm); 464 return 0; 465 } 466 467 hwsup = omap4_cminst_is_clkdm_in_hwsup(clkdm->prcm_partition, 468 clkdm->cm_inst, clkdm->clkdm_offs); 469 470 if (!hwsup && (clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) 471 omap4_clkdm_sleep(clkdm); 472 473 return 0; 474 } 475 476 static u32 omap4_cminst_xlate_clkctrl(u8 part, u16 inst, u16 offset) 477 { 478 return _cm_bases[part].pa + inst + offset; 479 } 480 481 /** 482 * omap4_clkdm_save_context - Save the clockdomain modulemode context 483 * @clkdm: The clockdomain pointer whose context needs to be saved 484 * 485 * Save the clockdomain modulemode context. 486 */ 487 static int omap4_clkdm_save_context(struct clockdomain *clkdm) 488 { 489 clkdm->context = omap4_cminst_read_inst_reg(clkdm->prcm_partition, 490 clkdm->cm_inst, 491 clkdm->clkdm_offs + 492 OMAP4_CM_CLKSTCTRL); 493 clkdm->context &= OMAP4430_MODULEMODE_MASK; 494 return 0; 495 } 496 497 /** 498 * omap4_clkdm_restore_context - Restore the clockdomain modulemode context 499 * @clkdm: The clockdomain pointer whose context needs to be restored 500 * 501 * Restore the clockdomain modulemode context. 502 */ 503 static int omap4_clkdm_restore_context(struct clockdomain *clkdm) 504 { 505 switch (clkdm->context) { 506 case OMAP34XX_CLKSTCTRL_DISABLE_AUTO: 507 omap4_clkdm_deny_idle(clkdm); 508 break; 509 case OMAP34XX_CLKSTCTRL_FORCE_SLEEP: 510 omap4_clkdm_sleep(clkdm); 511 break; 512 case OMAP34XX_CLKSTCTRL_FORCE_WAKEUP: 513 omap4_clkdm_wakeup(clkdm); 514 break; 515 case OMAP34XX_CLKSTCTRL_ENABLE_AUTO: 516 omap4_clkdm_allow_idle(clkdm); 517 break; 518 } 519 return 0; 520 } 521 522 struct clkdm_ops omap4_clkdm_operations = { 523 .clkdm_add_wkdep = omap4_clkdm_add_wkup_sleep_dep, 524 .clkdm_del_wkdep = omap4_clkdm_del_wkup_sleep_dep, 525 .clkdm_read_wkdep = omap4_clkdm_read_wkup_sleep_dep, 526 .clkdm_clear_all_wkdeps = omap4_clkdm_clear_all_wkup_sleep_deps, 527 .clkdm_add_sleepdep = omap4_clkdm_add_wkup_sleep_dep, 528 .clkdm_del_sleepdep = omap4_clkdm_del_wkup_sleep_dep, 529 .clkdm_read_sleepdep = omap4_clkdm_read_wkup_sleep_dep, 530 .clkdm_clear_all_sleepdeps = omap4_clkdm_clear_all_wkup_sleep_deps, 531 .clkdm_sleep = omap4_clkdm_sleep, 532 .clkdm_wakeup = omap4_clkdm_wakeup, 533 .clkdm_allow_idle = omap4_clkdm_allow_idle, 534 .clkdm_deny_idle = omap4_clkdm_deny_idle, 535 .clkdm_clk_enable = omap4_clkdm_clk_enable, 536 .clkdm_clk_disable = omap4_clkdm_clk_disable, 537 .clkdm_save_context = omap4_clkdm_save_context, 538 .clkdm_restore_context = omap4_clkdm_restore_context, 539 }; 540 541 struct clkdm_ops am43xx_clkdm_operations = { 542 .clkdm_sleep = omap4_clkdm_sleep, 543 .clkdm_wakeup = omap4_clkdm_wakeup, 544 .clkdm_allow_idle = omap4_clkdm_allow_idle, 545 .clkdm_deny_idle = omap4_clkdm_deny_idle, 546 .clkdm_clk_enable = omap4_clkdm_clk_enable, 547 .clkdm_clk_disable = omap4_clkdm_clk_disable, 548 }; 549 550 static const struct cm_ll_data omap4xxx_cm_ll_data = { 551 .wait_module_ready = &omap4_cminst_wait_module_ready, 552 .wait_module_idle = &omap4_cminst_wait_module_idle, 553 .module_enable = &omap4_cminst_module_enable, 554 .module_disable = &omap4_cminst_module_disable, 555 .xlate_clkctrl = &omap4_cminst_xlate_clkctrl, 556 }; 557 558 int __init omap4_cm_init(const struct omap_prcm_init_data *data) 559 { 560 omap_cm_base_init(); 561 562 return cm_register(&omap4xxx_cm_ll_data); 563 } 564 565 static void __exit omap4_cm_exit(void) 566 { 567 cm_unregister(&omap4xxx_cm_ll_data); 568 } 569 __exitcall(omap4_cm_exit); 570