arch/arm/plat-s3c24xx/cpu-freq.c

   1 /* linux/arch/arm/plat-s3c24xx/cpu-freq.c
   2  *
   3  * Copyright (c) 2006-2008 Simtec Electronics
   4  *      http://armlinux.simtec.co.uk/
   5  *      Ben Dooks <ben@simtec.co.uk>
   6  *
   7  * S3C24XX CPU Frequency scaling
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12 */
  13
  14 #include <linux/init.h>
  15 #include <linux/module.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/ioport.h>
  18 #include <linux/cpufreq.h>
  19 #include <linux/cpu.h>
  20 #include <linux/clk.h>
  21 #include <linux/err.h>
  22 #include <linux/io.h>
  23 #include <linux/sysdev.h>
  24 #include <linux/kobject.h>
  25 #include <linux/sysfs.h>
  26 #include <linux/slab.h>
  27
  28 #include <asm/mach/arch.h>
  29 #include <asm/mach/map.h>
  30
  31 #include <plat/cpu.h>
  32 #include <plat/clock.h>
  33 #include <plat/cpu-freq-core.h>
  34
  35 #include <mach/regs-clock.h>
  36
  37 /* note, cpufreq support deals in kHz, no Hz */
  38
  39 static struct cpufreq_driver s3c24xx_driver;
  40 static struct s3c_cpufreq_config cpu_cur;
  41 static struct s3c_iotimings s3c24xx_iotiming;
  42 static struct cpufreq_frequency_table *pll_reg;
  43 static unsigned int last_target = ~0;
  44 static unsigned int ftab_size;
  45 static struct cpufreq_frequency_table *ftab;
  46
  47 static struct clk *_clk_mpll;
  48 static struct clk *_clk_xtal;
  49 static struct clk *clk_fclk;
  50 static struct clk *clk_hclk;
  51 static struct clk *clk_pclk;
  52 static struct clk *clk_arm;
  53
  54 #ifdef CONFIG_CPU_FREQ_S3C24XX_DEBUGFS
  55 struct s3c_cpufreq_config *s3c_cpufreq_getconfig(void)
  56 {
  57         return &cpu_cur;
  58 }
  59
  60 struct s3c_iotimings *s3c_cpufreq_getiotimings(void)
  61 {
  62         return &s3c24xx_iotiming;
  63 }
  64 #endif /* CONFIG_CPU_FREQ_S3C24XX_DEBUGFS */
  65
  66 static void s3c_cpufreq_getcur(struct s3c_cpufreq_config *cfg)
  67 {
  68         unsigned long fclk, pclk, hclk, armclk;
  69
  70         cfg->freq.fclk = fclk = clk_get_rate(clk_fclk);
  71         cfg->freq.hclk = hclk = clk_get_rate(clk_hclk);
  72         cfg->freq.pclk = pclk = clk_get_rate(clk_pclk);
  73         cfg->freq.armclk = armclk = clk_get_rate(clk_arm);
  74
  75         cfg->pll.index = __raw_readl(S3C2410_MPLLCON);
  76         cfg->pll.frequency = fclk;
  77
  78         cfg->freq.hclk_tns = 1000000000 / (cfg->freq.hclk / 10);
  79
  80         cfg->divs.h_divisor = fclk / hclk;
  81         cfg->divs.p_divisor = fclk / pclk;
  82 }
  83
  84 static inline void s3c_cpufreq_calc(struct s3c_cpufreq_config *cfg)
  85 {
  86         unsigned long pll = cfg->pll.frequency;
  87
  88         cfg->freq.fclk = pll;
  89         cfg->freq.hclk = pll / cfg->divs.h_divisor;
  90         cfg->freq.pclk = pll / cfg->divs.p_divisor;
  91
  92         /* convert hclk into 10ths of nanoseconds for io calcs */
  93         cfg->freq.hclk_tns = 1000000000 / (cfg->freq.hclk / 10);
  94 }
  95
  96 static inline int closer(unsigned int target, unsigned int n, unsigned int c)
  97 {
  98         int diff_cur = abs(target - c);
  99         int diff_new = abs(target - n);
 100
 101         return (diff_new < diff_cur);
 102 }
 103
 104 static void s3c_cpufreq_show(const char *pfx,
 105                                  struct s3c_cpufreq_config *cfg)
 106 {
 107         s3c_freq_dbg("%s: Fvco=%u, F=%lu, A=%lu, H=%lu (%u), P=%lu (%u)\n",
 108                      pfx, cfg->pll.frequency, cfg->freq.fclk, cfg->freq.armclk,
 109                      cfg->freq.hclk, cfg->divs.h_divisor,
 110                      cfg->freq.pclk, cfg->divs.p_divisor);
 111 }
 112
 113 /* functions to wrapper the driver info calls to do the cpu specific work */
 114
 115 static void s3c_cpufreq_setio(struct s3c_cpufreq_config *cfg)
 116 {
 117         if (cfg->info->set_iotiming)
 118                 (cfg->info->set_iotiming)(cfg, &s3c24xx_iotiming);
 119 }
 120
 121 static int s3c_cpufreq_calcio(struct s3c_cpufreq_config *cfg)
 122 {
 123         if (cfg->info->calc_iotiming)
 124                 return (cfg->info->calc_iotiming)(cfg, &s3c24xx_iotiming);
 125
 126         return 0;
 127 }
 128
 129 static void s3c_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg)
 130 {
 131         (cfg->info->set_refresh)(cfg);
 132 }
 133
 134 static void s3c_cpufreq_setdivs(struct s3c_cpufreq_config *cfg)
 135 {
 136         (cfg->info->set_divs)(cfg);
 137 }
 138
 139 static int s3c_cpufreq_calcdivs(struct s3c_cpufreq_config *cfg)
 140 {
 141         return (cfg->info->calc_divs)(cfg);
 142 }
 143
 144 static void s3c_cpufreq_setfvco(struct s3c_cpufreq_config *cfg)
 145 {
 146         (cfg->info->set_fvco)(cfg);
 147 }
 148
 149 static inline void s3c_cpufreq_resume_clocks(void)
 150 {
 151         cpu_cur.info->resume_clocks();
 152 }
 153
 154 static inline void s3c_cpufreq_updateclk(struct clk *clk,
 155                                          unsigned int freq)
 156 {
 157         clk_set_rate(clk, freq);
 158 }
 159
 160 static int s3c_cpufreq_settarget(struct cpufreq_policy *policy,
 161                                  unsigned int target_freq,
 162                                  struct cpufreq_frequency_table *pll)
 163 {
 164         struct s3c_cpufreq_freqs freqs;
 165         struct s3c_cpufreq_config cpu_new;
 166         unsigned long flags;
 167
 168         cpu_new = cpu_cur;  /* copy new from current */
 169
 170         s3c_cpufreq_show("cur", &cpu_cur);
 171
 172         /* TODO - check for DMA currently outstanding */
 173
 174         cpu_new.pll = pll ? *pll : cpu_cur.pll;
 175
 176         if (pll)
 177                 freqs.pll_changing = 1;
 178
 179         /* update our frequencies */
 180
 181         cpu_new.freq.armclk = target_freq;
 182         cpu_new.freq.fclk = cpu_new.pll.frequency;
 183
 184         if (s3c_cpufreq_calcdivs(&cpu_new) < 0) {
 185                 printk(KERN_ERR "no divisors for %d\n", target_freq);
 186                 goto err_notpossible;
 187         }
 188
 189         s3c_freq_dbg("%s: got divs\n", __func__);
 190
 191         s3c_cpufreq_calc(&cpu_new);
 192
 193         s3c_freq_dbg("%s: calculated frequencies for new\n", __func__);
 194
 195         if (cpu_new.freq.hclk != cpu_cur.freq.hclk) {
 196                 if (s3c_cpufreq_calcio(&cpu_new) < 0) {
 197                         printk(KERN_ERR "%s: no IO timings\n", __func__);
 198                         goto err_notpossible;
 199                 }
 200         }
 201
 202         s3c_cpufreq_show("new", &cpu_new);
 203
 204         /* setup our cpufreq parameters */
 205
 206         freqs.old = cpu_cur.freq;
 207         freqs.new = cpu_new.freq;
 208
 209         freqs.freqs.cpu = 0;
 210         freqs.freqs.old = cpu_cur.freq.armclk / 1000;
 211         freqs.freqs.new = cpu_new.freq.armclk / 1000;
 212
 213         /* update f/h/p clock settings before we issue the change
 214          * notification, so that drivers do not need to do anything
 215          * special if they want to recalculate on CPUFREQ_PRECHANGE. */
 216
 217         s3c_cpufreq_updateclk(_clk_mpll, cpu_new.pll.frequency);
 218         s3c_cpufreq_updateclk(clk_fclk, cpu_new.freq.fclk);
 219         s3c_cpufreq_updateclk(clk_hclk, cpu_new.freq.hclk);
 220         s3c_cpufreq_updateclk(clk_pclk, cpu_new.freq.pclk);
 221
 222         /* start the frequency change */
 223
 224         if (policy)
 225                 cpufreq_notify_transition(&freqs.freqs, CPUFREQ_PRECHANGE);
 226
 227         /* If hclk is staying the same, then we do not need to
 228          * re-write the IO or the refresh timings whilst we are changing
 229          * speed. */
 230
 231         local_irq_save(flags);
 232
 233         /* is our memory clock slowing down? */
 234         if (cpu_new.freq.hclk < cpu_cur.freq.hclk) {
 235                 s3c_cpufreq_setrefresh(&cpu_new);
 236                 s3c_cpufreq_setio(&cpu_new);
 237         }
 238
 239         if (cpu_new.freq.fclk == cpu_cur.freq.fclk) {
 240                 /* not changing PLL, just set the divisors */
 241
 242                 s3c_cpufreq_setdivs(&cpu_new);
 243         } else {
 244                 if (cpu_new.freq.fclk < cpu_cur.freq.fclk) {
 245                         /* slow the cpu down, then set divisors */
 246
 247                         s3c_cpufreq_setfvco(&cpu_new);
 248                         s3c_cpufreq_setdivs(&cpu_new);
 249                 } else {
 250                         /* set the divisors, then speed up */
 251
 252                         s3c_cpufreq_setdivs(&cpu_new);
 253                         s3c_cpufreq_setfvco(&cpu_new);
 254                 }
 255         }
 256
 257         /* did our memory clock speed up */
 258         if (cpu_new.freq.hclk > cpu_cur.freq.hclk) {
 259                 s3c_cpufreq_setrefresh(&cpu_new);
 260                 s3c_cpufreq_setio(&cpu_new);
 261         }
 262
 263         /* update our current settings */
 264         cpu_cur = cpu_new;
 265
 266         local_irq_restore(flags);
 267
 268         /* notify everyone we've done this */
 269         if (policy)
 270                 cpufreq_notify_transition(&freqs.freqs, CPUFREQ_POSTCHANGE);
 271
 272         s3c_freq_dbg("%s: finished\n", __func__);
 273         return 0;
 274
 275  err_notpossible:
 276         printk(KERN_ERR "no compatible settings for %d\n", target_freq);
 277         return -EINVAL;
 278 }
 279
 280 /* s3c_cpufreq_target
 281  *
 282  * called by the cpufreq core to adjust the frequency that the CPU
 283  * is currently running at.
 284  */
 285
 286 static int s3c_cpufreq_target(struct cpufreq_policy *policy,
 287                               unsigned int target_freq,
 288                               unsigned int relation)
 289 {
 290         struct cpufreq_frequency_table *pll;
 291         unsigned int index;
 292
 293         /* avoid repeated calls which cause a needless amout of duplicated
 294          * logging output (and CPU time as the calculation process is
 295          * done) */
 296         if (target_freq == last_target)
 297                 return 0;
 298
 299         last_target = target_freq;
 300
 301         s3c_freq_dbg("%s: policy %p, target %u, relation %u\n",
 302                      __func__, policy, target_freq, relation);
 303
 304         if (ftab) {
 305                 if (cpufreq_frequency_table_target(policy, ftab,
 306                                                    target_freq, relation,
 307                                                    &index)) {
 308                         s3c_freq_dbg("%s: table failed\n", __func__);
 309                         return -EINVAL;
 310                 }
 311
 312                 s3c_freq_dbg("%s: adjust %d to entry %d (%u)\n", __func__,
 313                              target_freq, index, ftab[index].frequency);
 314                 target_freq = ftab[index].frequency;
 315         }
 316
 317         target_freq *= 1000;  /* convert target to Hz */
 318
 319         /* find the settings for our new frequency */
 320
 321         if (!pll_reg || cpu_cur.lock_pll) {
 322                 /* either we've not got any PLL values, or we've locked
 323                  * to the current one. */
 324                 pll = NULL;
 325         } else {
 326                 struct cpufreq_policy tmp_policy;
 327                 int ret;
 328
 329                 /* we keep the cpu pll table in Hz, to ensure we get an
 330                  * accurate value for the PLL output. */
 331
 332                 tmp_policy.min = policy->min * 1000;
 333                 tmp_policy.max = policy->max * 1000;
 334                 tmp_policy.cpu = policy->cpu;
 335
 336                 /* cpufreq_frequency_table_target uses a pointer to 'index'
 337                  * which is the number of the table entry, not the value of
 338                  * the table entry's index field. */
 339
 340                 ret = cpufreq_frequency_table_target(&tmp_policy, pll_reg,
 341                                                      target_freq, relation,
 342                                                      &index);
 343
 344                 if (ret < 0) {
 345                         printk(KERN_ERR "%s: no PLL available\n", __func__);
 346                         goto err_notpossible;
 347                 }
 348
 349                 pll = pll_reg + index;
 350
 351                 s3c_freq_dbg("%s: target %u => %u\n",
 352                              __func__, target_freq, pll->frequency);
 353
 354                 target_freq = pll->frequency;
 355         }
 356
 357         return s3c_cpufreq_settarget(policy, target_freq, pll);
 358
 359  err_notpossible:
 360         printk(KERN_ERR "no compatible settings for %d\n", target_freq);
 361         return -EINVAL;
 362 }
 363
 364 static unsigned int s3c_cpufreq_get(unsigned int cpu)
 365 {
 366         return clk_get_rate(clk_arm) / 1000;
 367 }
 368
 369 struct clk *s3c_cpufreq_clk_get(struct device *dev, const char *name)
 370 {
 371         struct clk *clk;
 372
 373         clk = clk_get(dev, name);
 374         if (IS_ERR(clk))
 375                 printk(KERN_ERR "cpufreq: failed to get clock '%s'\n", name);
 376
 377         return clk;
 378 }
 379
 380 static int s3c_cpufreq_init(struct cpufreq_policy *policy)
 381 {
 382         printk(KERN_INFO "%s: initialising policy %p\n", __func__, policy);
 383
 384         if (policy->cpu != 0)
 385                 return -EINVAL;
 386
 387         policy->cur = s3c_cpufreq_get(0);
 388         policy->min = policy->cpuinfo.min_freq = 0;
 389         policy->max = policy->cpuinfo.max_freq = cpu_cur.info->max.fclk / 1000;
 390         policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 391
 392         /* feed the latency information from the cpu driver */
 393         policy->cpuinfo.transition_latency = cpu_cur.info->latency;
 394
 395         if (ftab)
 396                 cpufreq_frequency_table_cpuinfo(policy, ftab);
 397
 398         return 0;
 399 }
 400
 401 static __init int s3c_cpufreq_initclks(void)
 402 {
 403         _clk_mpll = s3c_cpufreq_clk_get(NULL, "mpll");
 404         _clk_xtal = s3c_cpufreq_clk_get(NULL, "xtal");
 405         clk_fclk = s3c_cpufreq_clk_get(NULL, "fclk");
 406         clk_hclk = s3c_cpufreq_clk_get(NULL, "hclk");
 407         clk_pclk = s3c_cpufreq_clk_get(NULL, "pclk");
 408         clk_arm = s3c_cpufreq_clk_get(NULL, "armclk");
 409
 410         if (IS_ERR(clk_fclk) || IS_ERR(clk_hclk) || IS_ERR(clk_pclk) ||
 411             IS_ERR(_clk_mpll) || IS_ERR(clk_arm) || IS_ERR(_clk_xtal)) {
 412                 printk(KERN_ERR "%s: could not get clock(s)\n", __func__);
 413                 return -ENOENT;
 414         }
 415
 416         printk(KERN_INFO "%s: clocks f=%lu,h=%lu,p=%lu,a=%lu\n", __func__,
 417                clk_get_rate(clk_fclk) / 1000,
 418                clk_get_rate(clk_hclk) / 1000,
 419                clk_get_rate(clk_pclk) / 1000,
 420                clk_get_rate(clk_arm) / 1000);
 421
 422         return 0;
 423 }
 424
 425 static int s3c_cpufreq_verify(struct cpufreq_policy *policy)
 426 {
 427         if (policy->cpu != 0)
 428                 return -EINVAL;
 429
 430         return 0;
 431 }
 432
 433 #ifdef CONFIG_PM
 434 static struct cpufreq_frequency_table suspend_pll;
 435 static unsigned int suspend_freq;
 436
 437 static int s3c_cpufreq_suspend(struct cpufreq_policy *policy, pm_message_t pmsg)
 438 {
 439         suspend_pll.frequency = clk_get_rate(_clk_mpll);
 440         suspend_pll.index = __raw_readl(S3C2410_MPLLCON);
 441         suspend_freq = s3c_cpufreq_get(0) * 1000;
 442
 443         return 0;
 444 }
 445
 446 static int s3c_cpufreq_resume(struct cpufreq_policy *policy)
 447 {
 448         int ret;
 449
 450         s3c_freq_dbg("%s: resuming with policy %p\n", __func__, policy);
 451
 452         last_target = ~0;       /* invalidate last_target setting */
 453
 454         /* first, find out what speed we resumed at. */
 455         s3c_cpufreq_resume_clocks();
 456
 457         /* whilst we will be called later on, we try and re-set the
 458          * cpu frequencies as soon as possible so that we do not end
 459          * up resuming devices and then immediatley having to re-set
 460          * a number of settings once these devices have restarted.
 461          *
 462          * as a note, it is expected devices are not used until they
 463          * have been un-suspended and at that time they should have
 464          * used the updated clock settings.
 465          */
 466
 467         ret = s3c_cpufreq_settarget(NULL, suspend_freq, &suspend_pll);
 468         if (ret) {
 469                 printk(KERN_ERR "%s: failed to reset pll/freq\n", __func__);
 470                 return ret;
 471         }
 472
 473         return 0;
 474 }
 475 #else
 476 #define s3c_cpufreq_resume NULL
 477 #define s3c_cpufreq_suspend NULL
 478 #endif
 479
 480 static struct cpufreq_driver s3c24xx_driver = {
 481         .flags          = CPUFREQ_STICKY,
 482         .verify         = s3c_cpufreq_verify,
 483         .target         = s3c_cpufreq_target,
 484         .get            = s3c_cpufreq_get,
 485         .init           = s3c_cpufreq_init,
 486         .suspend        = s3c_cpufreq_suspend,
 487         .resume         = s3c_cpufreq_resume,
 488         .name           = "s3c24xx",
 489 };
 490
 491
 492 int __init s3c_cpufreq_register(struct s3c_cpufreq_info *info)
 493 {
 494         if (!info || !info->name) {
 495                 printk(KERN_ERR "%s: failed to pass valid information\n",
 496                        __func__);
 497                 return -EINVAL;
 498         }
 499
 500         printk(KERN_INFO "S3C24XX CPU Frequency driver, %s cpu support\n",
 501                info->name);
 502
 503         /* check our driver info has valid data */
 504
 505         BUG_ON(info->set_refresh == NULL);
 506         BUG_ON(info->set_divs == NULL);
 507         BUG_ON(info->calc_divs == NULL);
 508
 509         /* info->set_fvco is optional, depending on whether there
 510          * is a need to set the clock code. */
 511
 512         cpu_cur.info = info;
 513
 514         /* Note, driver registering should probably update locktime */
 515
 516         return 0;
 517 }
 518
 519 int __init s3c_cpufreq_setboard(struct s3c_cpufreq_board *board)
 520 {
 521         struct s3c_cpufreq_board *ours;
 522
 523         if (!board) {
 524                 printk(KERN_INFO "%s: no board data\n", __func__);
 525                 return -EINVAL;
 526         }
 527
 528         /* Copy the board information so that each board can make this
 529          * initdata. */
 530
 531         ours = kzalloc(sizeof(struct s3c_cpufreq_board), GFP_KERNEL);
 532         if (ours == NULL) {
 533                 printk(KERN_ERR "%s: no memory\n", __func__);
 534                 return -ENOMEM;
 535         }
 536
 537         *ours = *board;
 538         cpu_cur.board = ours;
 539
 540         return 0;
 541 }
 542
 543 int __init s3c_cpufreq_auto_io(void)
 544 {
 545         int ret;
 546
 547         if (!cpu_cur.info->get_iotiming) {
 548                 printk(KERN_ERR "%s: get_iotiming undefined\n", __func__);
 549                 return -ENOENT;
 550         }
 551
 552         printk(KERN_INFO "%s: working out IO settings\n", __func__);
 553
 554         ret = (cpu_cur.info->get_iotiming)(&cpu_cur, &s3c24xx_iotiming);
 555         if (ret)
 556                 printk(KERN_ERR "%s: failed to get timings\n", __func__);
 557
 558         return ret;
 559 }
 560
 561 /* if one or is zero, then return the other, otherwise return the min */
 562 #define do_min(_a, _b) ((_a) == 0 ? (_b) : (_b) == 0 ? (_a) : min(_a, _b))
 563
 564 /**
 565  * s3c_cpufreq_freq_min - find the minimum settings for the given freq.
 566  * @dst: The destination structure
 567  * @a: One argument.
 568  * @b: The other argument.
 569  *
 570  * Create a minimum of each frequency entry in the 'struct s3c_freq',
 571  * unless the entry is zero when it is ignored and the non-zero argument
 572  * used.
 573  */
 574 static void s3c_cpufreq_freq_min(struct s3c_freq *dst,
 575                                  struct s3c_freq *a, struct s3c_freq *b)
 576 {
 577         dst->fclk = do_min(a->fclk, b->fclk);
 578         dst->hclk = do_min(a->hclk, b->hclk);
 579         dst->pclk = do_min(a->pclk, b->pclk);
 580         dst->armclk = do_min(a->armclk, b->armclk);
 581 }
 582
 583 static inline u32 calc_locktime(u32 freq, u32 time_us)
 584 {
 585         u32 result;
 586
 587         result = freq * time_us;
 588         result = DIV_ROUND_UP(result, 1000 * 1000);
 589
 590         return result;
 591 }
 592
 593 static void s3c_cpufreq_update_loctkime(void)
 594 {
 595         unsigned int bits = cpu_cur.info->locktime_bits;
 596         u32 rate = (u32)clk_get_rate(_clk_xtal);
 597         u32 val;
 598
 599         if (bits == 0) {
 600                 WARN_ON(1);
 601                 return;
 602         }
 603
 604         val = calc_locktime(rate, cpu_cur.info->locktime_u) << bits;
 605         val |= calc_locktime(rate, cpu_cur.info->locktime_m);
 606
 607         printk(KERN_INFO "%s: new locktime is 0x%08x\n", __func__, val);
 608         __raw_writel(val, S3C2410_LOCKTIME);
 609 }
 610
 611 static int s3c_cpufreq_build_freq(void)
 612 {
 613         int size, ret;
 614
 615         if (!cpu_cur.info->calc_freqtable)
 616                 return -EINVAL;
 617
 618         kfree(ftab);
 619         ftab = NULL;
 620
 621         size = cpu_cur.info->calc_freqtable(&cpu_cur, NULL, 0);
 622         size++;
 623
 624         ftab = kmalloc(sizeof(struct cpufreq_frequency_table) * size, GFP_KERNEL);
 625         if (!ftab) {
 626                 printk(KERN_ERR "%s: no memory for tables\n", __func__);
 627                 return -ENOMEM;
 628         }
 629
 630         ftab_size = size;
 631
 632         ret = cpu_cur.info->calc_freqtable(&cpu_cur, ftab, size);
 633         s3c_cpufreq_addfreq(ftab, ret, size, CPUFREQ_TABLE_END);
 634
 635         return 0;
 636 }
 637
 638 static int __init s3c_cpufreq_initcall(void)
 639 {
 640         int ret = 0;
 641
 642         if (cpu_cur.info && cpu_cur.board) {
 643                 ret = s3c_cpufreq_initclks();
 644                 if (ret)
 645                         goto out;
 646
 647                 /* get current settings */
 648                 s3c_cpufreq_getcur(&cpu_cur);
 649                 s3c_cpufreq_show("cur", &cpu_cur);
 650
 651                 if (cpu_cur.board->auto_io) {
 652                         ret = s3c_cpufreq_auto_io();
 653                         if (ret) {
 654                                 printk(KERN_ERR "%s: failed to get io timing\n",
 655                                        __func__);
 656                                 goto out;
 657                         }
 658                 }
 659
 660                 if (cpu_cur.board->need_io && !cpu_cur.info->set_iotiming) {
 661                         printk(KERN_ERR "%s: no IO support registered\n",
 662                                __func__);
 663                         ret = -EINVAL;
 664                         goto out;
 665                 }
 666
 667                 if (!cpu_cur.info->need_pll)
 668                         cpu_cur.lock_pll = 1;
 669
 670                 s3c_cpufreq_update_loctkime();
 671
 672                 s3c_cpufreq_freq_min(&cpu_cur.max, &cpu_cur.board->max,
 673                                      &cpu_cur.info->max);
 674
 675                 if (cpu_cur.info->calc_freqtable)
 676                         s3c_cpufreq_build_freq();
 677
 678                 ret = cpufreq_register_driver(&s3c24xx_driver);
 679         }
 680
 681  out:
 682         return ret;
 683 }
 684
 685 late_initcall(s3c_cpufreq_initcall);
 686
 687 /**
 688  * s3c_plltab_register - register CPU PLL table.
 689  * @plls: The list of PLL entries.
 690  * @plls_no: The size of the PLL entries @plls.
 691  *
 692  * Register the given set of PLLs with the system.
 693  */
 694 int __init s3c_plltab_register(struct cpufreq_frequency_table *plls,
 695                                unsigned int plls_no)
 696 {
 697         struct cpufreq_frequency_table *vals;
 698         unsigned int size;
 699
 700         size = sizeof(struct cpufreq_frequency_table) * (plls_no + 1);
 701
 702         vals = kmalloc(size, GFP_KERNEL);
 703         if (vals) {
 704                 memcpy(vals, plls, size);
 705                 pll_reg = vals;
 706
 707                 /* write a terminating entry, we don't store it in the
 708                  * table that is stored in the kernel */
 709                 vals += plls_no;
 710                 vals->frequency = CPUFREQ_TABLE_END;
 711
 712                 printk(KERN_INFO "cpufreq: %d PLL entries\n", plls_no);
 713         } else
 714                 printk(KERN_ERR "cpufreq: no memory for PLL tables\n");
 715
 716         return vals ? 0 : -ENOMEM;
 717 }