drivers/cpufreq/exynos4210-cpufreq.c

   1 /*
   2  * Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
   3  *              http://www.samsung.com
   4  *
   5  * EXYNOS4 - CPU frequency scaling support
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10 */
  11
  12 #include <linux/types.h>
  13 #include <linux/kernel.h>
  14 #include <linux/err.h>
  15 #include <linux/clk.h>
  16 #include <linux/io.h>
  17 #include <linux/slab.h>
  18 #include <linux/regulator/consumer.h>
  19 #include <linux/cpufreq.h>
  20 #include <linux/notifier.h>
  21 #include <linux/suspend.h>
  22
  23 #include <mach/map.h>
  24 #include <mach/regs-clock.h>
  25 #include <mach/regs-mem.h>
  26
  27 #include <plat/clock.h>
  28 #include <plat/pm.h>
  29
  30 static struct clk *cpu_clk;
  31 static struct clk *moutcore;
  32 static struct clk *mout_mpll;
  33 static struct clk *mout_apll;
  34
  35 static struct regulator *arm_regulator;
  36 static struct regulator *int_regulator;
  37
  38 static struct cpufreq_freqs freqs;
  39 static unsigned int memtype;
  40
  41 static unsigned int locking_frequency;
  42 static bool frequency_locked;
  43 static DEFINE_MUTEX(cpufreq_lock);
  44
  45 enum exynos4_memory_type {
  46         DDR2 = 4,
  47         LPDDR2,
  48         DDR3,
  49 };
  50
  51 enum cpufreq_level_index {
  52         L0, L1, L2, L3, CPUFREQ_LEVEL_END,
  53 };
  54
  55 static struct cpufreq_frequency_table exynos4_freq_table[] = {
  56         {L0, 1000*1000},
  57         {L1, 800*1000},
  58         {L2, 400*1000},
  59         {L3, 100*1000},
  60         {0, CPUFREQ_TABLE_END},
  61 };
  62
  63 static unsigned int clkdiv_cpu0[CPUFREQ_LEVEL_END][7] = {
  64         /*
  65          * Clock divider value for following
  66          * { DIVCORE, DIVCOREM0, DIVCOREM1, DIVPERIPH,
  67          *              DIVATB, DIVPCLK_DBG, DIVAPLL }
  68          */
  69
  70         /* ARM L0: 1000MHz */
  71         { 0, 3, 7, 3, 3, 0, 1 },
  72
  73         /* ARM L1: 800MHz */
  74         { 0, 3, 7, 3, 3, 0, 1 },
  75
  76         /* ARM L2: 400MHz */
  77         { 0, 1, 3, 1, 3, 0, 1 },
  78
  79         /* ARM L3: 100MHz */
  80         { 0, 0, 1, 0, 3, 1, 1 },
  81 };
  82
  83 static unsigned int clkdiv_cpu1[CPUFREQ_LEVEL_END][2] = {
  84         /*
  85          * Clock divider value for following
  86          * { DIVCOPY, DIVHPM }
  87          */
  88
  89          /* ARM L0: 1000MHz */
  90         { 3, 0 },
  91
  92         /* ARM L1: 800MHz */
  93         { 3, 0 },
  94
  95         /* ARM L2: 400MHz */
  96         { 3, 0 },
  97
  98         /* ARM L3: 100MHz */
  99         { 3, 0 },
 100 };
 101
 102 static unsigned int clkdiv_dmc0[CPUFREQ_LEVEL_END][8] = {
 103         /*
 104          * Clock divider value for following
 105          * { DIVACP, DIVACP_PCLK, DIVDPHY, DIVDMC, DIVDMCD
 106          *              DIVDMCP, DIVCOPY2, DIVCORE_TIMERS }
 107          */
 108
 109         /* DMC L0: 400MHz */
 110         { 3, 1, 1, 1, 1, 1, 3, 1 },
 111
 112         /* DMC L1: 400MHz */
 113         { 3, 1, 1, 1, 1, 1, 3, 1 },
 114
 115         /* DMC L2: 266.7MHz */
 116         { 7, 1, 1, 2, 1, 1, 3, 1 },
 117
 118         /* DMC L3: 200MHz */
 119         { 7, 1, 1, 3, 1, 1, 3, 1 },
 120 };
 121
 122 static unsigned int clkdiv_top[CPUFREQ_LEVEL_END][5] = {
 123         /*
 124          * Clock divider value for following
 125          * { DIVACLK200, DIVACLK100, DIVACLK160, DIVACLK133, DIVONENAND }
 126          */
 127
 128         /* ACLK200 L0: 200MHz */
 129         { 3, 7, 4, 5, 1 },
 130
 131         /* ACLK200 L1: 200MHz */
 132         { 3, 7, 4, 5, 1 },
 133
 134         /* ACLK200 L2: 160MHz */
 135         { 4, 7, 5, 7, 1 },
 136
 137         /* ACLK200 L3: 133.3MHz */
 138         { 5, 7, 7, 7, 1 },
 139 };
 140
 141 static unsigned int clkdiv_lr_bus[CPUFREQ_LEVEL_END][2] = {
 142         /*
 143          * Clock divider value for following
 144          * { DIVGDL/R, DIVGPL/R }
 145          */
 146
 147         /* ACLK_GDL/R L0: 200MHz */
 148         { 3, 1 },
 149
 150         /* ACLK_GDL/R L1: 200MHz */
 151         { 3, 1 },
 152
 153         /* ACLK_GDL/R L2: 160MHz */
 154         { 4, 1 },
 155
 156         /* ACLK_GDL/R L3: 133.3MHz */
 157         { 5, 1 },
 158 };
 159
 160 struct cpufreq_voltage_table {
 161         unsigned int    index;          /* any */
 162         unsigned int    arm_volt;       /* uV */
 163         unsigned int    int_volt;
 164 };
 165
 166 static struct cpufreq_voltage_table exynos4_volt_table[CPUFREQ_LEVEL_END] = {
 167         {
 168                 .index          = L0,
 169                 .arm_volt       = 1200000,
 170                 .int_volt       = 1100000,
 171         }, {
 172                 .index          = L1,
 173                 .arm_volt       = 1100000,
 174                 .int_volt       = 1100000,
 175         }, {
 176                 .index          = L2,
 177                 .arm_volt       = 1000000,
 178                 .int_volt       = 1000000,
 179         }, {
 180                 .index          = L3,
 181                 .arm_volt       = 900000,
 182                 .int_volt       = 1000000,
 183         },
 184 };
 185
 186 static unsigned int exynos4_apll_pms_table[CPUFREQ_LEVEL_END] = {
 187         /* APLL FOUT L0: 1000MHz */
 188         ((250 << 16) | (6 << 8) | 1),
 189
 190         /* APLL FOUT L1: 800MHz */
 191         ((200 << 16) | (6 << 8) | 1),
 192
 193         /* APLL FOUT L2 : 400MHz */
 194         ((200 << 16) | (6 << 8) | 2),
 195
 196         /* APLL FOUT L3: 100MHz */
 197         ((200 << 16) | (6 << 8) | 4),
 198 };
 199
 200 static int exynos4_verify_speed(struct cpufreq_policy *policy)
 201 {
 202         return cpufreq_frequency_table_verify(policy, exynos4_freq_table);
 203 }
 204
 205 static unsigned int exynos4_getspeed(unsigned int cpu)
 206 {
 207         return clk_get_rate(cpu_clk) / 1000;
 208 }
 209
 210 static void exynos4_set_clkdiv(unsigned int div_index)
 211 {
 212         unsigned int tmp;
 213
 214         /* Change Divider - CPU0 */
 215
 216         tmp = __raw_readl(S5P_CLKDIV_CPU);
 217
 218         tmp &= ~(S5P_CLKDIV_CPU0_CORE_MASK | S5P_CLKDIV_CPU0_COREM0_MASK |
 219                 S5P_CLKDIV_CPU0_COREM1_MASK | S5P_CLKDIV_CPU0_PERIPH_MASK |
 220                 S5P_CLKDIV_CPU0_ATB_MASK | S5P_CLKDIV_CPU0_PCLKDBG_MASK |
 221                 S5P_CLKDIV_CPU0_APLL_MASK);
 222
 223         tmp |= ((clkdiv_cpu0[div_index][0] << S5P_CLKDIV_CPU0_CORE_SHIFT) |
 224                 (clkdiv_cpu0[div_index][1] << S5P_CLKDIV_CPU0_COREM0_SHIFT) |
 225                 (clkdiv_cpu0[div_index][2] << S5P_CLKDIV_CPU0_COREM1_SHIFT) |
 226                 (clkdiv_cpu0[div_index][3] << S5P_CLKDIV_CPU0_PERIPH_SHIFT) |
 227                 (clkdiv_cpu0[div_index][4] << S5P_CLKDIV_CPU0_ATB_SHIFT) |
 228                 (clkdiv_cpu0[div_index][5] << S5P_CLKDIV_CPU0_PCLKDBG_SHIFT) |
 229                 (clkdiv_cpu0[div_index][6] << S5P_CLKDIV_CPU0_APLL_SHIFT));
 230
 231         __raw_writel(tmp, S5P_CLKDIV_CPU);
 232
 233         do {
 234                 tmp = __raw_readl(S5P_CLKDIV_STATCPU);
 235         } while (tmp & 0x1111111);
 236
 237         /* Change Divider - CPU1 */
 238
 239         tmp = __raw_readl(S5P_CLKDIV_CPU1);
 240
 241         tmp &= ~((0x7 << 4) | 0x7);
 242
 243         tmp |= ((clkdiv_cpu1[div_index][0] << 4) |
 244                 (clkdiv_cpu1[div_index][1] << 0));
 245
 246         __raw_writel(tmp, S5P_CLKDIV_CPU1);
 247
 248         do {
 249                 tmp = __raw_readl(S5P_CLKDIV_STATCPU1);
 250         } while (tmp & 0x11);
 251
 252         /* Change Divider - DMC0 */
 253
 254         tmp = __raw_readl(S5P_CLKDIV_DMC0);
 255
 256         tmp &= ~(S5P_CLKDIV_DMC0_ACP_MASK | S5P_CLKDIV_DMC0_ACPPCLK_MASK |
 257                 S5P_CLKDIV_DMC0_DPHY_MASK | S5P_CLKDIV_DMC0_DMC_MASK |
 258                 S5P_CLKDIV_DMC0_DMCD_MASK | S5P_CLKDIV_DMC0_DMCP_MASK |
 259                 S5P_CLKDIV_DMC0_COPY2_MASK | S5P_CLKDIV_DMC0_CORETI_MASK);
 260
 261         tmp |= ((clkdiv_dmc0[div_index][0] << S5P_CLKDIV_DMC0_ACP_SHIFT) |
 262                 (clkdiv_dmc0[div_index][1] << S5P_CLKDIV_DMC0_ACPPCLK_SHIFT) |
 263                 (clkdiv_dmc0[div_index][2] << S5P_CLKDIV_DMC0_DPHY_SHIFT) |
 264                 (clkdiv_dmc0[div_index][3] << S5P_CLKDIV_DMC0_DMC_SHIFT) |
 265                 (clkdiv_dmc0[div_index][4] << S5P_CLKDIV_DMC0_DMCD_SHIFT) |
 266                 (clkdiv_dmc0[div_index][5] << S5P_CLKDIV_DMC0_DMCP_SHIFT) |
 267                 (clkdiv_dmc0[div_index][6] << S5P_CLKDIV_DMC0_COPY2_SHIFT) |
 268                 (clkdiv_dmc0[div_index][7] << S5P_CLKDIV_DMC0_CORETI_SHIFT));
 269
 270         __raw_writel(tmp, S5P_CLKDIV_DMC0);
 271
 272         do {
 273                 tmp = __raw_readl(S5P_CLKDIV_STAT_DMC0);
 274         } while (tmp & 0x11111111);
 275
 276         /* Change Divider - TOP */
 277
 278         tmp = __raw_readl(S5P_CLKDIV_TOP);
 279
 280         tmp &= ~(S5P_CLKDIV_TOP_ACLK200_MASK | S5P_CLKDIV_TOP_ACLK100_MASK |
 281                 S5P_CLKDIV_TOP_ACLK160_MASK | S5P_CLKDIV_TOP_ACLK133_MASK |
 282                 S5P_CLKDIV_TOP_ONENAND_MASK);
 283
 284         tmp |= ((clkdiv_top[div_index][0] << S5P_CLKDIV_TOP_ACLK200_SHIFT) |
 285                 (clkdiv_top[div_index][1] << S5P_CLKDIV_TOP_ACLK100_SHIFT) |
 286                 (clkdiv_top[div_index][2] << S5P_CLKDIV_TOP_ACLK160_SHIFT) |
 287                 (clkdiv_top[div_index][3] << S5P_CLKDIV_TOP_ACLK133_SHIFT) |
 288                 (clkdiv_top[div_index][4] << S5P_CLKDIV_TOP_ONENAND_SHIFT));
 289
 290         __raw_writel(tmp, S5P_CLKDIV_TOP);
 291
 292         do {
 293                 tmp = __raw_readl(S5P_CLKDIV_STAT_TOP);
 294         } while (tmp & 0x11111);
 295
 296         /* Change Divider - LEFTBUS */
 297
 298         tmp = __raw_readl(S5P_CLKDIV_LEFTBUS);
 299
 300         tmp &= ~(S5P_CLKDIV_BUS_GDLR_MASK | S5P_CLKDIV_BUS_GPLR_MASK);
 301
 302         tmp |= ((clkdiv_lr_bus[div_index][0] << S5P_CLKDIV_BUS_GDLR_SHIFT) |
 303                 (clkdiv_lr_bus[div_index][1] << S5P_CLKDIV_BUS_GPLR_SHIFT));
 304
 305         __raw_writel(tmp, S5P_CLKDIV_LEFTBUS);
 306
 307         do {
 308                 tmp = __raw_readl(S5P_CLKDIV_STAT_LEFTBUS);
 309         } while (tmp & 0x11);
 310
 311         /* Change Divider - RIGHTBUS */
 312
 313         tmp = __raw_readl(S5P_CLKDIV_RIGHTBUS);
 314
 315         tmp &= ~(S5P_CLKDIV_BUS_GDLR_MASK | S5P_CLKDIV_BUS_GPLR_MASK);
 316
 317         tmp |= ((clkdiv_lr_bus[div_index][0] << S5P_CLKDIV_BUS_GDLR_SHIFT) |
 318                 (clkdiv_lr_bus[div_index][1] << S5P_CLKDIV_BUS_GPLR_SHIFT));
 319
 320         __raw_writel(tmp, S5P_CLKDIV_RIGHTBUS);
 321
 322         do {
 323                 tmp = __raw_readl(S5P_CLKDIV_STAT_RIGHTBUS);
 324         } while (tmp & 0x11);
 325 }
 326
 327 static void exynos4_set_apll(unsigned int index)
 328 {
 329         unsigned int tmp;
 330
 331         /* 1. MUX_CORE_SEL = MPLL, ARMCLK uses MPLL for lock time */
 332         clk_set_parent(moutcore, mout_mpll);
 333
 334         do {
 335                 tmp = (__raw_readl(S5P_CLKMUX_STATCPU)
 336                         >> S5P_CLKSRC_CPU_MUXCORE_SHIFT);
 337                 tmp &= 0x7;
 338         } while (tmp != 0x2);
 339
 340         /* 2. Set APLL Lock time */
 341         __raw_writel(S5P_APLL_LOCKTIME, S5P_APLL_LOCK);
 342
 343         /* 3. Change PLL PMS values */
 344         tmp = __raw_readl(S5P_APLL_CON0);
 345         tmp &= ~((0x3ff << 16) | (0x3f << 8) | (0x7 << 0));
 346         tmp |= exynos4_apll_pms_table[index];
 347         __raw_writel(tmp, S5P_APLL_CON0);
 348
 349         /* 4. wait_lock_time */
 350         do {
 351                 tmp = __raw_readl(S5P_APLL_CON0);
 352         } while (!(tmp & (0x1 << S5P_APLLCON0_LOCKED_SHIFT)));
 353
 354         /* 5. MUX_CORE_SEL = APLL */
 355         clk_set_parent(moutcore, mout_apll);
 356
 357         do {
 358                 tmp = __raw_readl(S5P_CLKMUX_STATCPU);
 359                 tmp &= S5P_CLKMUX_STATCPU_MUXCORE_MASK;
 360         } while (tmp != (0x1 << S5P_CLKSRC_CPU_MUXCORE_SHIFT));
 361 }
 362
 363 static void exynos4_set_frequency(unsigned int old_index, unsigned int new_index)
 364 {
 365         unsigned int tmp;
 366
 367         if (old_index > new_index) {
 368                 /* The frequency changing to L0 needs to change apll */
 369                 if (freqs.new == exynos4_freq_table[L0].frequency) {
 370                         /* 1. Change the system clock divider values */
 371                         exynos4_set_clkdiv(new_index);
 372
 373                         /* 2. Change the apll m,p,s value */
 374                         exynos4_set_apll(new_index);
 375                 } else {
 376                         /* 1. Change the system clock divider values */
 377                         exynos4_set_clkdiv(new_index);
 378
 379                         /* 2. Change just s value in apll m,p,s value */
 380                         tmp = __raw_readl(S5P_APLL_CON0);
 381                         tmp &= ~(0x7 << 0);
 382                         tmp |= (exynos4_apll_pms_table[new_index] & 0x7);
 383                         __raw_writel(tmp, S5P_APLL_CON0);
 384                 }
 385         }
 386
 387         else if (old_index < new_index) {
 388                 /* The frequency changing from L0 needs to change apll */
 389                 if (freqs.old == exynos4_freq_table[L0].frequency) {
 390                         /* 1. Change the apll m,p,s value */
 391                         exynos4_set_apll(new_index);
 392
 393                         /* 2. Change the system clock divider values */
 394                         exynos4_set_clkdiv(new_index);
 395                 } else {
 396                         /* 1. Change just s value in apll m,p,s value */
 397                         tmp = __raw_readl(S5P_APLL_CON0);
 398                         tmp &= ~(0x7 << 0);
 399                         tmp |= (exynos4_apll_pms_table[new_index] & 0x7);
 400                         __raw_writel(tmp, S5P_APLL_CON0);
 401
 402                         /* 2. Change the system clock divider values */
 403                         exynos4_set_clkdiv(new_index);
 404                 }
 405         }
 406 }
 407
 408 static int exynos4_target(struct cpufreq_policy *policy,
 409                           unsigned int target_freq,
 410                           unsigned int relation)
 411 {
 412         unsigned int index, old_index;
 413         unsigned int arm_volt, int_volt;
 414         int err = -EINVAL;
 415
 416         freqs.old = exynos4_getspeed(policy->cpu);
 417
 418         mutex_lock(&cpufreq_lock);
 419
 420         if (frequency_locked && target_freq != locking_frequency) {
 421                 err = -EAGAIN;
 422                 goto out;
 423         }
 424
 425         if (cpufreq_frequency_table_target(policy, exynos4_freq_table,
 426                                            freqs.old, relation, &old_index))
 427                 goto out;
 428
 429         if (cpufreq_frequency_table_target(policy, exynos4_freq_table,
 430                                            target_freq, relation, &index))
 431                 goto out;
 432
 433         err = 0;
 434
 435         freqs.new = exynos4_freq_table[index].frequency;
 436         freqs.cpu = policy->cpu;
 437
 438         if (freqs.new == freqs.old)
 439                 goto out;
 440
 441         /* get the voltage value */
 442         arm_volt = exynos4_volt_table[index].arm_volt;
 443         int_volt = exynos4_volt_table[index].int_volt;
 444
 445         cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
 446
 447         /* control regulator */
 448         if (freqs.new > freqs.old) {
 449                 /* Voltage up */
 450                 regulator_set_voltage(arm_regulator, arm_volt, arm_volt);
 451                 regulator_set_voltage(int_regulator, int_volt, int_volt);
 452         }
 453
 454         /* Clock Configuration Procedure */
 455         exynos4_set_frequency(old_index, index);
 456
 457         /* control regulator */
 458         if (freqs.new < freqs.old) {
 459                 /* Voltage down */
 460                 regulator_set_voltage(arm_regulator, arm_volt, arm_volt);
 461                 regulator_set_voltage(int_regulator, int_volt, int_volt);
 462         }
 463
 464         cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
 465
 466 out:
 467         mutex_unlock(&cpufreq_lock);
 468         return err;
 469 }
 470
 471 #ifdef CONFIG_PM
 472 /*
 473  * These suspend/resume are used as syscore_ops, it is already too
 474  * late to set regulator voltages at this stage.
 475  */
 476 static int exynos4_cpufreq_suspend(struct cpufreq_policy *policy)
 477 {
 478         return 0;
 479 }
 480
 481 static int exynos4_cpufreq_resume(struct cpufreq_policy *policy)
 482 {
 483         return 0;
 484 }
 485 #endif
 486
 487 /**
 488  * exynos4_cpufreq_pm_notifier - block CPUFREQ's activities in suspend-resume
 489  *                      context
 490  * @notifier
 491  * @pm_event
 492  * @v
 493  *
 494  * While frequency_locked == true, target() ignores every frequency but
 495  * locking_frequency. The locking_frequency value is the initial frequency,
 496  * which is set by the bootloader. In order to eliminate possible
 497  * inconsistency in clock values, we save and restore frequencies during
 498  * suspend and resume and block CPUFREQ activities. Note that the standard
 499  * suspend/resume cannot be used as they are too deep (syscore_ops) for
 500  * regulator actions.
 501  */
 502 static int exynos4_cpufreq_pm_notifier(struct notifier_block *notifier,
 503                                        unsigned long pm_event, void *v)
 504 {
 505         struct cpufreq_policy *policy = cpufreq_cpu_get(0); /* boot CPU */
 506         static unsigned int saved_frequency;
 507         unsigned int temp;
 508
 509         mutex_lock(&cpufreq_lock);
 510         switch (pm_event) {
 511         case PM_SUSPEND_PREPARE:
 512                 if (frequency_locked)
 513                         goto out;
 514                 frequency_locked = true;
 515
 516                 if (locking_frequency) {
 517                         saved_frequency = exynos4_getspeed(0);
 518
 519                         mutex_unlock(&cpufreq_lock);
 520                         exynos4_target(policy, locking_frequency,
 521                                        CPUFREQ_RELATION_H);
 522                         mutex_lock(&cpufreq_lock);
 523                 }
 524
 525                 break;
 526         case PM_POST_SUSPEND:
 527
 528                 if (saved_frequency) {
 529                         /*
 530                          * While frequency_locked, only locking_frequency
 531                          * is valid for target(). In order to use
 532                          * saved_frequency while keeping frequency_locked,
 533                          * we temporarly overwrite locking_frequency.
 534                          */
 535                         temp = locking_frequency;
 536                         locking_frequency = saved_frequency;
 537
 538                         mutex_unlock(&cpufreq_lock);
 539                         exynos4_target(policy, locking_frequency,
 540                                        CPUFREQ_RELATION_H);
 541                         mutex_lock(&cpufreq_lock);
 542
 543                         locking_frequency = temp;
 544                 }
 545
 546                 frequency_locked = false;
 547                 break;
 548         }
 549 out:
 550         mutex_unlock(&cpufreq_lock);
 551
 552         return NOTIFY_OK;
 553 }
 554
 555 static struct notifier_block exynos4_cpufreq_nb = {
 556         .notifier_call = exynos4_cpufreq_pm_notifier,
 557 };
 558
 559 static int exynos4_cpufreq_cpu_init(struct cpufreq_policy *policy)
 560 {
 561         int ret;
 562
 563         policy->cur = policy->min = policy->max = exynos4_getspeed(policy->cpu);
 564
 565         cpufreq_frequency_table_get_attr(exynos4_freq_table, policy->cpu);
 566
 567         /* set the transition latency value */
 568         policy->cpuinfo.transition_latency = 100000;
 569
 570         /*
 571          * EXYNOS4 multi-core processors has 2 cores
 572          * that the frequency cannot be set independently.
 573          * Each cpu is bound to the same speed.
 574          * So the affected cpu is all of the cpus.
 575          */
 576         cpumask_setall(policy->cpus);
 577
 578         ret = cpufreq_frequency_table_cpuinfo(policy, exynos4_freq_table);
 579         if (ret)
 580                 return ret;
 581
 582         cpufreq_frequency_table_get_attr(exynos4_freq_table, policy->cpu);
 583
 584         return 0;
 585 }
 586
 587 static int exynos4_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 588 {
 589         cpufreq_frequency_table_put_attr(policy->cpu);
 590         return 0;
 591 }
 592
 593 static struct freq_attr *exynos4_cpufreq_attr[] = {
 594         &cpufreq_freq_attr_scaling_available_freqs,
 595         NULL,
 596 };
 597
 598 static struct cpufreq_driver exynos4_driver = {
 599         .flags          = CPUFREQ_STICKY,
 600         .verify         = exynos4_verify_speed,
 601         .target         = exynos4_target,
 602         .get            = exynos4_getspeed,
 603         .init           = exynos4_cpufreq_cpu_init,
 604         .exit           = exynos4_cpufreq_cpu_exit,
 605         .name           = "exynos4_cpufreq",
 606         .attr           = exynos4_cpufreq_attr,
 607 #ifdef CONFIG_PM
 608         .suspend        = exynos4_cpufreq_suspend,
 609         .resume         = exynos4_cpufreq_resume,
 610 #endif
 611 };
 612
 613 static int __init exynos4_cpufreq_init(void)
 614 {
 615         cpu_clk = clk_get(NULL, "armclk");
 616         if (IS_ERR(cpu_clk))
 617                 return PTR_ERR(cpu_clk);
 618
 619         locking_frequency = exynos4_getspeed(0);
 620
 621         moutcore = clk_get(NULL, "moutcore");
 622         if (IS_ERR(moutcore))
 623                 goto out;
 624
 625         mout_mpll = clk_get(NULL, "mout_mpll");
 626         if (IS_ERR(mout_mpll))
 627                 goto out;
 628
 629         mout_apll = clk_get(NULL, "mout_apll");
 630         if (IS_ERR(mout_apll))
 631                 goto out;
 632
 633         arm_regulator = regulator_get(NULL, "vdd_arm");
 634         if (IS_ERR(arm_regulator)) {
 635                 printk(KERN_ERR "failed to get resource %s\n", "vdd_arm");
 636                 goto out;
 637         }
 638
 639         int_regulator = regulator_get(NULL, "vdd_int");
 640         if (IS_ERR(int_regulator)) {
 641                 printk(KERN_ERR "failed to get resource %s\n", "vdd_int");
 642                 goto out;
 643         }
 644
 645         /*
 646          * Check DRAM type.
 647          * Because DVFS level is different according to DRAM type.
 648          */
 649         memtype = __raw_readl(S5P_VA_DMC0 + S5P_DMC0_MEMCON_OFFSET);
 650         memtype = (memtype >> S5P_DMC0_MEMTYPE_SHIFT);
 651         memtype &= S5P_DMC0_MEMTYPE_MASK;
 652
 653         if ((memtype < DDR2) && (memtype > DDR3)) {
 654                 printk(KERN_ERR "%s: wrong memtype= 0x%x\n", __func__, memtype);
 655                 goto out;
 656         } else {
 657                 printk(KERN_DEBUG "%s: memtype= 0x%x\n", __func__, memtype);
 658         }
 659
 660         register_pm_notifier(&exynos4_cpufreq_nb);
 661
 662         return cpufreq_register_driver(&exynos4_driver);
 663
 664 out:
 665         if (!IS_ERR(cpu_clk))
 666                 clk_put(cpu_clk);
 667
 668         if (!IS_ERR(moutcore))
 669                 clk_put(moutcore);
 670
 671         if (!IS_ERR(mout_mpll))
 672                 clk_put(mout_mpll);
 673
 674         if (!IS_ERR(mout_apll))
 675                 clk_put(mout_apll);
 676
 677         if (!IS_ERR(arm_regulator))
 678                 regulator_put(arm_regulator);
 679
 680         if (!IS_ERR(int_regulator))
 681                 regulator_put(int_regulator);
 682
 683         printk(KERN_ERR "%s: failed initialization\n", __func__);
 684
 685         return -EINVAL;
 686 }
 687 late_initcall(exynos4_cpufreq_init);