arch/arm/mach-omap2/clock.c

   1 /*
   2  *  linux/arch/arm/mach-omap2/clock.c
   3  *
   4  *  Copyright (C) 2005 Texas Instruments Inc.
   5  *  Richard Woodruff <r-woodruff2@ti.com>
   6  *  Created for OMAP2.
   7  *
   8  *  Cleaned up and modified to use omap shared clock framework by
   9  *  Tony Lindgren <tony@atomide.com>
  10  *
  11  *  Based on omap1 clock.c, Copyright (C) 2004 - 2005 Nokia corporation
  12  *  Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License version 2 as
  16  * published by the Free Software Foundation.
  17  */
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/device.h>
  21 #include <linux/list.h>
  22 #include <linux/errno.h>
  23 #include <linux/delay.h>
  24 #include <linux/clk.h>
  25
  26 #include <asm/io.h>
  27
  28 #include <asm/arch/clock.h>
  29 #include <asm/arch/sram.h>
  30 #include <asm/div64.h>
  31
  32 #include "prcm-regs.h"
  33 #include "memory.h"
  34 #include "clock.h"
  35
  36 #undef DEBUG
  37
  38 //#define DOWN_VARIABLE_DPLL 1                  /* Experimental */
  39
  40 static struct prcm_config *curr_prcm_set;
  41 static u32 curr_perf_level = PRCM_FULL_SPEED;
  42 static struct clk *vclk;
  43 static struct clk *sclk;
  44
  45 /*-------------------------------------------------------------------------
  46  * Omap2 specific clock functions
  47  *-------------------------------------------------------------------------*/
  48
  49 /* Recalculate SYST_CLK */
  50 static void omap2_sys_clk_recalc(struct clk * clk)
  51 {
  52         u32 div = PRCM_CLKSRC_CTRL;
  53         div &= (1 << 7) | (1 << 6);     /* Test if ext clk divided by 1 or 2 */
  54         div >>= clk->rate_offset;
  55         clk->rate = (clk->parent->rate / div);
  56         propagate_rate(clk);
  57 }
  58
  59 static u32 omap2_get_dpll_rate(struct clk * tclk)
  60 {
  61         long long dpll_clk;
  62         int dpll_mult, dpll_div, amult;
  63
  64         dpll_mult = (CM_CLKSEL1_PLL >> 12) & 0x03ff;    /* 10 bits */
  65         dpll_div = (CM_CLKSEL1_PLL >> 8) & 0x0f;        /* 4 bits */
  66         dpll_clk = (long long)tclk->parent->rate * dpll_mult;
  67         do_div(dpll_clk, dpll_div + 1);
  68         amult = CM_CLKSEL2_PLL & 0x3;
  69         dpll_clk *= amult;
  70
  71         return dpll_clk;
  72 }
  73
  74 static void omap2_followparent_recalc(struct clk *clk)
  75 {
  76         followparent_recalc(clk);
  77 }
  78
  79 static void omap2_propagate_rate(struct clk * clk)
  80 {
  81         if (!(clk->flags & RATE_FIXED))
  82                 clk->rate = clk->parent->rate;
  83
  84         propagate_rate(clk);
  85 }
  86
  87 static void omap2_set_osc_ck(int enable)
  88 {
  89         if (enable)
  90                 PRCM_CLKSRC_CTRL &= ~(0x3 << 3);
  91         else
  92                 PRCM_CLKSRC_CTRL |= 0x3 << 3;
  93 }
  94
  95 /* Enable an APLL if off */
  96 static void omap2_clk_fixed_enable(struct clk *clk)
  97 {
  98         u32 cval, i=0;
  99
 100         if (clk->enable_bit == 0xff)                    /* Parent will do it */
 101                 return;
 102
 103         cval = CM_CLKEN_PLL;
 104
 105         if ((cval & (0x3 << clk->enable_bit)) == (0x3 << clk->enable_bit))
 106                 return;
 107
 108         cval &= ~(0x3 << clk->enable_bit);
 109         cval |= (0x3 << clk->enable_bit);
 110         CM_CLKEN_PLL = cval;
 111
 112         if (clk == &apll96_ck)
 113                 cval = (1 << 8);
 114         else if (clk == &apll54_ck)
 115                 cval = (1 << 6);
 116
 117         while (!(CM_IDLEST_CKGEN & cval)) {             /* Wait for lock */
 118                 ++i;
 119                 udelay(1);
 120                 if (i == 100000) {
 121                         printk(KERN_ERR "Clock %s didn't lock\n", clk->name);
 122                         break;
 123                 }
 124         }
 125 }
 126
 127 static void omap2_clk_wait_ready(struct clk *clk)
 128 {
 129         unsigned long reg, other_reg, st_reg;
 130         u32 bit;
 131         int i;
 132
 133         reg = (unsigned long) clk->enable_reg;
 134         if (reg == (unsigned long) &CM_FCLKEN1_CORE ||
 135             reg == (unsigned long) &CM_FCLKEN2_CORE)
 136                 other_reg = (reg & ~0xf0) | 0x10;
 137         else if (reg == (unsigned long) &CM_ICLKEN1_CORE ||
 138                  reg == (unsigned long) &CM_ICLKEN2_CORE)
 139                 other_reg = (reg & ~0xf0) | 0x00;
 140         else
 141                 return;
 142
 143         /* No check for DSS or cam clocks */
 144         if ((reg & 0x0f) == 0) {
 145                 if (clk->enable_bit <= 1 || clk->enable_bit == 31)
 146                         return;
 147         }
 148
 149         /* Check if both functional and interface clocks
 150          * are running. */
 151         bit = 1 << clk->enable_bit;
 152         if (!(__raw_readl(other_reg) & bit))
 153                 return;
 154         st_reg = (other_reg & ~0xf0) | 0x20;
 155         i = 0;
 156         while (!(__raw_readl(st_reg) & bit)) {
 157                 i++;
 158                 if (i == 100000) {
 159                         printk(KERN_ERR "Timeout enabling clock %s\n", clk->name);
 160                         break;
 161                 }
 162         }
 163         if (i)
 164                 pr_debug("Clock %s stable after %d loops\n", clk->name, i);
 165 }
 166
 167 /* Enables clock without considering parent dependencies or use count
 168  * REVISIT: Maybe change this to use clk->enable like on omap1?
 169  */
 170 static int _omap2_clk_enable(struct clk * clk)
 171 {
 172         u32 regval32;
 173
 174         if (clk->flags & ALWAYS_ENABLED)
 175                 return 0;
 176
 177         if (unlikely(clk == &osc_ck)) {
 178                 omap2_set_osc_ck(1);
 179                 return 0;
 180         }
 181
 182         if (unlikely(clk->enable_reg == 0)) {
 183                 printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
 184                        clk->name);
 185                 return 0;
 186         }
 187
 188         if (clk->enable_reg == (void __iomem *)&CM_CLKEN_PLL) {
 189                 omap2_clk_fixed_enable(clk);
 190                 return 0;
 191         }
 192
 193         regval32 = __raw_readl(clk->enable_reg);
 194         regval32 |= (1 << clk->enable_bit);
 195         __raw_writel(regval32, clk->enable_reg);
 196         wmb();
 197
 198         omap2_clk_wait_ready(clk);
 199
 200         return 0;
 201 }
 202
 203 /* Stop APLL */
 204 static void omap2_clk_fixed_disable(struct clk *clk)
 205 {
 206         u32 cval;
 207
 208         if(clk->enable_bit == 0xff)             /* let parent off do it */
 209                 return;
 210
 211         cval = CM_CLKEN_PLL;
 212         cval &= ~(0x3 << clk->enable_bit);
 213         CM_CLKEN_PLL = cval;
 214 }
 215
 216 /* Disables clock without considering parent dependencies or use count */
 217 static void _omap2_clk_disable(struct clk *clk)
 218 {
 219         u32 regval32;
 220
 221         if (unlikely(clk == &osc_ck)) {
 222                 omap2_set_osc_ck(0);
 223                 return;
 224         }
 225
 226         if (clk->enable_reg == 0)
 227                 return;
 228
 229         if (clk->enable_reg == (void __iomem *)&CM_CLKEN_PLL) {
 230                 omap2_clk_fixed_disable(clk);
 231                 return;
 232         }
 233
 234         regval32 = __raw_readl(clk->enable_reg);
 235         regval32 &= ~(1 << clk->enable_bit);
 236         __raw_writel(regval32, clk->enable_reg);
 237         wmb();
 238 }
 239
 240 static int omap2_clk_enable(struct clk *clk)
 241 {
 242         int ret = 0;
 243
 244         if (clk->usecount++ == 0) {
 245                 if (likely((u32)clk->parent))
 246                         ret = omap2_clk_enable(clk->parent);
 247
 248                 if (unlikely(ret != 0)) {
 249                         clk->usecount--;
 250                         return ret;
 251                 }
 252
 253                 ret = _omap2_clk_enable(clk);
 254
 255                 if (unlikely(ret != 0) && clk->parent) {
 256                         omap2_clk_disable(clk->parent);
 257                         clk->usecount--;
 258                 }
 259         }
 260
 261         return ret;
 262 }
 263
 264 static void omap2_clk_disable(struct clk *clk)
 265 {
 266         if (clk->usecount > 0 && !(--clk->usecount)) {
 267                 _omap2_clk_disable(clk);
 268                 if (likely((u32)clk->parent))
 269                         omap2_clk_disable(clk->parent);
 270         }
 271 }
 272
 273 /*
 274  * Uses the current prcm set to tell if a rate is valid.
 275  * You can go slower, but not faster within a given rate set.
 276  */
 277 static u32 omap2_dpll_round_rate(unsigned long target_rate)
 278 {
 279         u32 high, low;
 280
 281         if ((CM_CLKSEL2_PLL & 0x3) == 1) {      /* DPLL clockout */
 282                 high = curr_prcm_set->dpll_speed * 2;
 283                 low = curr_prcm_set->dpll_speed;
 284         } else {                                /* DPLL clockout x 2 */
 285                 high = curr_prcm_set->dpll_speed;
 286                 low = curr_prcm_set->dpll_speed / 2;
 287         }
 288
 289 #ifdef DOWN_VARIABLE_DPLL
 290         if (target_rate > high)
 291                 return high;
 292         else
 293                 return target_rate;
 294 #else
 295         if (target_rate > low)
 296                 return high;
 297         else
 298                 return low;
 299 #endif
 300
 301 }
 302
 303 /*
 304  * Used for clocks that are part of CLKSEL_xyz governed clocks.
 305  * REVISIT: Maybe change to use clk->enable() functions like on omap1?
 306  */
 307 static void omap2_clksel_recalc(struct clk * clk)
 308 {
 309         u32 fixed = 0, div = 0;
 310
 311         if (clk == &dpll_ck) {
 312                 clk->rate = omap2_get_dpll_rate(clk);
 313                 fixed = 1;
 314                 div = 0;
 315         }
 316
 317         if (clk == &iva1_mpu_int_ifck) {
 318                 div = 2;
 319                 fixed = 1;
 320         }
 321
 322         if ((clk == &dss1_fck) && ((CM_CLKSEL1_CORE & (0x1f << 8)) == 0)) {
 323                 clk->rate = sys_ck.rate;
 324                 return;
 325         }
 326
 327         if (!fixed) {
 328                 div = omap2_clksel_get_divisor(clk);
 329                 if (div == 0)
 330                         return;
 331         }
 332
 333         if (div != 0) {
 334                 if (unlikely(clk->rate == clk->parent->rate / div))
 335                         return;
 336                 clk->rate = clk->parent->rate / div;
 337         }
 338
 339         if (unlikely(clk->flags & RATE_PROPAGATES))
 340                 propagate_rate(clk);
 341 }
 342
 343 /*
 344  * Finds best divider value in an array based on the source and target
 345  * rates. The divider array must be sorted with smallest divider first.
 346  */
 347 static inline u32 omap2_divider_from_table(u32 size, u32 *div_array,
 348                                            u32 src_rate, u32 tgt_rate)
 349 {
 350         int i, test_rate;
 351
 352         if (div_array == NULL)
 353                 return ~1;
 354
 355         for (i=0; i < size; i++) {
 356                 test_rate = src_rate / *div_array;
 357                 if (test_rate <= tgt_rate)
 358                         return *div_array;
 359                 ++div_array;
 360         }
 361
 362         return ~0;      /* No acceptable divider */
 363 }
 364
 365 /*
 366  * Find divisor for the given clock and target rate.
 367  *
 368  * Note that this will not work for clocks which are part of CONFIG_PARTICIPANT,
 369  * they are only settable as part of virtual_prcm set.
 370  */
 371 static u32 omap2_clksel_round_rate(struct clk *tclk, u32 target_rate,
 372         u32 *new_div)
 373 {
 374         u32 gfx_div[] = {2, 3, 4};
 375         u32 sysclkout_div[] = {1, 2, 4, 8, 16};
 376         u32 dss1_div[] = {1, 2, 3, 4, 5, 6, 8, 9, 12, 16};
 377         u32 vylnq_div[] = {1, 2, 3, 4, 6, 8, 9, 12, 16, 18};
 378         u32 best_div = ~0, asize = 0;
 379         u32 *div_array = NULL;
 380
 381         switch (tclk->flags & SRC_RATE_SEL_MASK) {
 382         case CM_GFX_SEL1:
 383                 asize = 3;
 384                 div_array = gfx_div;
 385                 break;
 386         case CM_PLL_SEL1:
 387                 return omap2_dpll_round_rate(target_rate);
 388         case CM_SYSCLKOUT_SEL1:
 389                 asize = 5;
 390                 div_array = sysclkout_div;
 391                 break;
 392         case CM_CORE_SEL1:
 393                 if(tclk == &dss1_fck){
 394                         if(tclk->parent == &core_ck){
 395                                 asize = 10;
 396                                 div_array = dss1_div;
 397                         } else {
 398                                 *new_div = 0; /* fixed clk */
 399                                 return(tclk->parent->rate);
 400                         }
 401                 } else if((tclk == &vlynq_fck) && cpu_is_omap2420()){
 402                         if(tclk->parent == &core_ck){
 403                                 asize = 10;
 404                                 div_array = vylnq_div;
 405                         } else {
 406                                 *new_div = 0; /* fixed clk */
 407                                 return(tclk->parent->rate);
 408                         }
 409                 }
 410                 break;
 411         }
 412
 413         best_div = omap2_divider_from_table(asize, div_array,
 414          tclk->parent->rate, target_rate);
 415         if (best_div == ~0){
 416                 *new_div = 1;
 417                 return best_div; /* signal error */
 418         }
 419
 420         *new_div = best_div;
 421         return (tclk->parent->rate / best_div);
 422 }
 423
 424 /* Given a clock and a rate apply a clock specific rounding function */
 425 static long omap2_clk_round_rate(struct clk *clk, unsigned long rate)
 426 {
 427         u32 new_div = 0;
 428         int valid_rate;
 429
 430         if (clk->flags & RATE_FIXED)
 431                 return clk->rate;
 432
 433         if (clk->flags & RATE_CKCTL) {
 434                 valid_rate = omap2_clksel_round_rate(clk, rate, &new_div);
 435                 return valid_rate;
 436         }
 437
 438         if (clk->round_rate != 0)
 439                 return clk->round_rate(clk, rate);
 440
 441         return clk->rate;
 442 }
 443
 444 /*
 445  * Check the DLL lock state, and return tue if running in unlock mode.
 446  * This is needed to compensate for the shifted DLL value in unlock mode.
 447  */
 448 static u32 omap2_dll_force_needed(void)
 449 {
 450         u32 dll_state = SDRC_DLLA_CTRL;         /* dlla and dllb are a set */
 451
 452         if ((dll_state & (1 << 2)) == (1 << 2))
 453                 return 1;
 454         else
 455                 return 0;
 456 }
 457
 458 static u32 omap2_reprogram_sdrc(u32 level, u32 force)
 459 {
 460         u32 slow_dll_ctrl, fast_dll_ctrl, m_type;
 461         u32 prev = curr_perf_level, flags;
 462
 463         if ((curr_perf_level == level) && !force)
 464                 return prev;
 465
 466         m_type = omap2_memory_get_type();
 467         slow_dll_ctrl = omap2_memory_get_slow_dll_ctrl();
 468         fast_dll_ctrl = omap2_memory_get_fast_dll_ctrl();
 469
 470         if (level == PRCM_HALF_SPEED) {
 471                 local_irq_save(flags);
 472                 PRCM_VOLTSETUP = 0xffff;
 473                 omap2_sram_reprogram_sdrc(PRCM_HALF_SPEED,
 474                                           slow_dll_ctrl, m_type);
 475                 curr_perf_level = PRCM_HALF_SPEED;
 476                 local_irq_restore(flags);
 477         }
 478         if (level == PRCM_FULL_SPEED) {
 479                 local_irq_save(flags);
 480                 PRCM_VOLTSETUP = 0xffff;
 481                 omap2_sram_reprogram_sdrc(PRCM_FULL_SPEED,
 482                                           fast_dll_ctrl, m_type);
 483                 curr_perf_level = PRCM_FULL_SPEED;
 484                 local_irq_restore(flags);
 485         }
 486
 487         return prev;
 488 }
 489
 490 static int omap2_reprogram_dpll(struct clk * clk, unsigned long rate)
 491 {
 492         u32 flags, cur_rate, low, mult, div, valid_rate, done_rate;
 493         u32 bypass = 0;
 494         struct prcm_config tmpset;
 495         int ret = -EINVAL;
 496
 497         local_irq_save(flags);
 498         cur_rate = omap2_get_dpll_rate(&dpll_ck);
 499         mult = CM_CLKSEL2_PLL & 0x3;
 500
 501         if ((rate == (cur_rate / 2)) && (mult == 2)) {
 502                 omap2_reprogram_sdrc(PRCM_HALF_SPEED, 1);
 503         } else if ((rate == (cur_rate * 2)) && (mult == 1)) {
 504                 omap2_reprogram_sdrc(PRCM_FULL_SPEED, 1);
 505         } else if (rate != cur_rate) {
 506                 valid_rate = omap2_dpll_round_rate(rate);
 507                 if (valid_rate != rate)
 508                         goto dpll_exit;
 509
 510                 if ((CM_CLKSEL2_PLL & 0x3) == 1)
 511                         low = curr_prcm_set->dpll_speed;
 512                 else
 513                         low = curr_prcm_set->dpll_speed / 2;
 514
 515                 tmpset.cm_clksel1_pll = CM_CLKSEL1_PLL;
 516                 tmpset.cm_clksel1_pll &= ~(0x3FFF << 8);
 517                 div = ((curr_prcm_set->xtal_speed / 1000000) - 1);
 518                 tmpset.cm_clksel2_pll = CM_CLKSEL2_PLL;
 519                 tmpset.cm_clksel2_pll &= ~0x3;
 520                 if (rate > low) {
 521                         tmpset.cm_clksel2_pll |= 0x2;
 522                         mult = ((rate / 2) / 1000000);
 523                         done_rate = PRCM_FULL_SPEED;
 524                 } else {
 525                         tmpset.cm_clksel2_pll |= 0x1;
 526                         mult = (rate / 1000000);
 527                         done_rate = PRCM_HALF_SPEED;
 528                 }
 529                 tmpset.cm_clksel1_pll |= ((div << 8) | (mult << 12));
 530
 531                 /* Worst case */
 532                 tmpset.base_sdrc_rfr = V24XX_SDRC_RFR_CTRL_BYPASS;
 533
 534                 if (rate == curr_prcm_set->xtal_speed)  /* If asking for 1-1 */
 535                         bypass = 1;
 536
 537                 omap2_reprogram_sdrc(PRCM_FULL_SPEED, 1); /* For init_mem */
 538
 539                 /* Force dll lock mode */
 540                 omap2_set_prcm(tmpset.cm_clksel1_pll, tmpset.base_sdrc_rfr,
 541                                bypass);
 542
 543                 /* Errata: ret dll entry state */
 544                 omap2_init_memory_params(omap2_dll_force_needed());
 545                 omap2_reprogram_sdrc(done_rate, 0);
 546         }
 547         omap2_clksel_recalc(&dpll_ck);
 548         ret = 0;
 549
 550 dpll_exit:
 551         local_irq_restore(flags);
 552         return(ret);
 553 }
 554
 555 /* Just return the MPU speed */
 556 static void omap2_mpu_recalc(struct clk * clk)
 557 {
 558         clk->rate = curr_prcm_set->mpu_speed;
 559 }
 560
 561 /*
 562  * Look for a rate equal or less than the target rate given a configuration set.
 563  *
 564  * What's not entirely clear is "which" field represents the key field.
 565  * Some might argue L3-DDR, others ARM, others IVA. This code is simple and
 566  * just uses the ARM rates.
 567  */
 568 static long omap2_round_to_table_rate(struct clk * clk, unsigned long rate)
 569 {
 570         struct prcm_config * ptr;
 571         long highest_rate;
 572
 573         if (clk != &virt_prcm_set)
 574                 return -EINVAL;
 575
 576         highest_rate = -EINVAL;
 577
 578         for (ptr = rate_table; ptr->mpu_speed; ptr++) {
 579                 if (ptr->xtal_speed != sys_ck.rate)
 580                         continue;
 581
 582                 highest_rate = ptr->mpu_speed;
 583
 584                 /* Can check only after xtal frequency check */
 585                 if (ptr->mpu_speed <= rate)
 586                         break;
 587         }
 588         return highest_rate;
 589 }
 590
 591 /*
 592  * omap2_convert_field_to_div() - turn field value into integer divider
 593  */
 594 static u32 omap2_clksel_to_divisor(u32 div_sel, u32 field_val)
 595 {
 596         u32 i;
 597         u32 clkout_array[] = {1, 2, 4, 8, 16};
 598
 599         if ((div_sel & SRC_RATE_SEL_MASK) == CM_SYSCLKOUT_SEL1) {
 600                 for (i = 0; i < 5; i++) {
 601                         if (field_val == i)
 602                                 return clkout_array[i];
 603                 }
 604                 return ~0;
 605         } else
 606                 return field_val;
 607 }
 608
 609 /*
 610  * Returns the CLKSEL divider register value
 611  * REVISIT: This should be cleaned up to work nicely with void __iomem *
 612  */
 613 static u32 omap2_get_clksel(u32 *div_sel, u32 *field_mask,
 614                             struct clk *clk)
 615 {
 616         int ret = ~0;
 617         u32 reg_val, div_off;
 618         u32 div_addr = 0;
 619         u32 mask = ~0;
 620
 621         div_off = clk->rate_offset;
 622
 623         switch ((*div_sel & SRC_RATE_SEL_MASK)) {
 624         case CM_MPU_SEL1:
 625                 div_addr = (u32)&CM_CLKSEL_MPU;
 626                 mask = 0x1f;
 627                 break;
 628         case CM_DSP_SEL1:
 629                 div_addr = (u32)&CM_CLKSEL_DSP;
 630                 if (cpu_is_omap2420()) {
 631                         if ((div_off == 0) || (div_off == 8))
 632                                 mask = 0x1f;
 633                         else if (div_off == 5)
 634                                 mask = 0x3;
 635                 } else if (cpu_is_omap2430()) {
 636                         if (div_off == 0)
 637                                 mask = 0x1f;
 638                         else if (div_off == 5)
 639                                 mask = 0x3;
 640                 }
 641                 break;
 642         case CM_GFX_SEL1:
 643                 div_addr = (u32)&CM_CLKSEL_GFX;
 644                 if (div_off == 0)
 645                         mask = 0x7;
 646                 break;
 647         case CM_MODEM_SEL1:
 648                 div_addr = (u32)&CM_CLKSEL_MDM;
 649                 if (div_off == 0)
 650                         mask = 0xf;
 651                 break;
 652         case CM_SYSCLKOUT_SEL1:
 653                 div_addr = (u32)&PRCM_CLKOUT_CTRL;
 654                 if ((div_off == 3) || (div_off == 11))
 655                         mask= 0x3;
 656                 break;
 657         case CM_CORE_SEL1:
 658                 div_addr = (u32)&CM_CLKSEL1_CORE;
 659                 switch (div_off) {
 660                 case 0:                                 /* l3 */
 661                 case 8:                                 /* dss1 */
 662                 case 15:                                /* vylnc-2420 */
 663                 case 20:                                /* ssi */
 664                         mask = 0x1f; break;
 665                 case 5:                                 /* l4 */
 666                         mask = 0x3; break;
 667                 case 13:                                /* dss2 */
 668                         mask = 0x1; break;
 669                 case 25:                                /* usb */
 670                         mask = 0x7; break;
 671                 }
 672         }
 673
 674         *field_mask = mask;
 675
 676         if (unlikely(mask == ~0))
 677                 div_addr = 0;
 678
 679         *div_sel = div_addr;
 680
 681         if (unlikely(div_addr == 0))
 682                 return ret;
 683
 684         /* Isolate field */
 685         reg_val = __raw_readl((void __iomem *)div_addr) & (mask << div_off);
 686
 687         /* Normalize back to divider value */
 688         reg_val >>= div_off;
 689
 690         return reg_val;
 691 }
 692
 693 /*
 694  * Return divider to be applied to parent clock.
 695  * Return 0 on error.
 696  */
 697 static u32 omap2_clksel_get_divisor(struct clk *clk)
 698 {
 699         int ret = 0;
 700         u32 div, div_sel, div_off, field_mask, field_val;
 701
 702         /* isolate control register */
 703         div_sel = (SRC_RATE_SEL_MASK & clk->flags);
 704
 705         div_off = clk->rate_offset;
 706         field_val = omap2_get_clksel(&div_sel, &field_mask, clk);
 707         if (div_sel == 0)
 708                 return ret;
 709
 710         div_sel = (SRC_RATE_SEL_MASK & clk->flags);
 711         div = omap2_clksel_to_divisor(div_sel, field_val);
 712
 713         return div;
 714 }
 715
 716 /* Set the clock rate for a clock source */
 717 static int omap2_clk_set_rate(struct clk *clk, unsigned long rate)
 718
 719 {
 720         int ret = -EINVAL;
 721         void __iomem * reg;
 722         u32 div_sel, div_off, field_mask, field_val, reg_val, validrate;
 723         u32 new_div = 0;
 724
 725         if (!(clk->flags & CONFIG_PARTICIPANT) && (clk->flags & RATE_CKCTL)) {
 726                 if (clk == &dpll_ck)
 727                         return omap2_reprogram_dpll(clk, rate);
 728
 729                 /* Isolate control register */
 730                 div_sel = (SRC_RATE_SEL_MASK & clk->flags);
 731                 div_off = clk->rate_offset;
 732
 733                 validrate = omap2_clksel_round_rate(clk, rate, &new_div);
 734                 if (validrate != rate)
 735                         return(ret);
 736
 737                 field_val = omap2_get_clksel(&div_sel, &field_mask, clk);
 738                 if (div_sel == 0)
 739                         return ret;
 740
 741                 if (clk->flags & CM_SYSCLKOUT_SEL1) {
 742                         switch (new_div) {
 743                         case 16:
 744                                 field_val = 4;
 745                                 break;
 746                         case 8:
 747                                 field_val = 3;
 748                                 break;
 749                         case 4:
 750                                 field_val = 2;
 751                                 break;
 752                         case 2:
 753                                 field_val = 1;
 754                                 break;
 755                         case 1:
 756                                 field_val = 0;
 757                                 break;
 758                         }
 759                 } else
 760                         field_val = new_div;
 761
 762                 reg = (void __iomem *)div_sel;
 763
 764                 reg_val = __raw_readl(reg);
 765                 reg_val &= ~(field_mask << div_off);
 766                 reg_val |= (field_val << div_off);
 767                 __raw_writel(reg_val, reg);
 768                 wmb();
 769                 clk->rate = clk->parent->rate / field_val;
 770
 771                 if (clk->flags & DELAYED_APP) {
 772                         __raw_writel(0x1, (void __iomem *)&PRCM_CLKCFG_CTRL);
 773                         wmb();
 774                 }
 775                 ret = 0;
 776         } else if (clk->set_rate != 0)
 777                 ret = clk->set_rate(clk, rate);
 778
 779         if (unlikely(ret == 0 && (clk->flags & RATE_PROPAGATES)))
 780                 propagate_rate(clk);
 781
 782         return ret;
 783 }
 784
 785 /* Converts encoded control register address into a full address */
 786 static u32 omap2_get_src_field(u32 *type_to_addr, u32 reg_offset,
 787                                struct clk *src_clk, u32 *field_mask)
 788 {
 789         u32 val = ~0, src_reg_addr = 0, mask = 0;
 790
 791         /* Find target control register.*/
 792         switch ((*type_to_addr & SRC_RATE_SEL_MASK)) {
 793         case CM_CORE_SEL1:
 794                 src_reg_addr = (u32)&CM_CLKSEL1_CORE;
 795                 if (reg_offset == 13) {                 /* DSS2_fclk */
 796                         mask = 0x1;
 797                         if (src_clk == &sys_ck)
 798                                 val = 0;
 799                         if (src_clk == &func_48m_ck)
 800                                 val = 1;
 801                 } else if (reg_offset == 8) {           /* DSS1_fclk */
 802                         mask = 0x1f;
 803                         if (src_clk == &sys_ck)
 804                                 val = 0;
 805                         else if (src_clk == &core_ck)   /* divided clock */
 806                                 val = 0x10;             /* rate needs fixing */
 807                 } else if ((reg_offset == 15) && cpu_is_omap2420()){ /*vlnyq*/
 808                         mask = 0x1F;
 809                         if(src_clk == &func_96m_ck)
 810                                 val = 0;
 811                         else if (src_clk == &core_ck)
 812                                 val = 0x10;
 813                 }
 814                 break;
 815         case CM_CORE_SEL2:
 816                 src_reg_addr = (u32)&CM_CLKSEL2_CORE;
 817                 mask = 0x3;
 818                 if (src_clk == &func_32k_ck)
 819                         val = 0x0;
 820                 if (src_clk == &sys_ck)
 821                         val = 0x1;
 822                 if (src_clk == &alt_ck)
 823                         val = 0x2;
 824                 break;
 825         case CM_WKUP_SEL1:
 826                 src_reg_addr = (u32)&CM_CLKSEL_WKUP;
 827                 mask = 0x3;
 828                 if (src_clk == &func_32k_ck)
 829                         val = 0x0;
 830                 if (src_clk == &sys_ck)
 831                         val = 0x1;
 832                 if (src_clk == &alt_ck)
 833                         val = 0x2;
 834                 break;
 835         case CM_PLL_SEL1:
 836                 src_reg_addr = (u32)&CM_CLKSEL1_PLL;
 837                 mask = 0x1;
 838                 if (reg_offset == 0x3) {
 839                         if (src_clk == &apll96_ck)
 840                                 val = 0;
 841                         if (src_clk == &alt_ck)
 842                                 val = 1;
 843                 }
 844                 else if (reg_offset == 0x5) {
 845                         if (src_clk == &apll54_ck)
 846                                 val = 0;
 847                         if (src_clk == &alt_ck)
 848                                 val = 1;
 849                 }
 850                 break;
 851         case CM_PLL_SEL2:
 852                 src_reg_addr = (u32)&CM_CLKSEL2_PLL;
 853                 mask = 0x3;
 854                 if (src_clk == &func_32k_ck)
 855                         val = 0x0;
 856                 if (src_clk == &dpll_ck)
 857                         val = 0x2;
 858                 break;
 859         case CM_SYSCLKOUT_SEL1:
 860                 src_reg_addr = (u32)&PRCM_CLKOUT_CTRL;
 861                 mask = 0x3;
 862                 if (src_clk == &dpll_ck)
 863                         val = 0;
 864                 if (src_clk == &sys_ck)
 865                         val = 1;
 866                 if (src_clk == &func_96m_ck)
 867                         val = 2;
 868                 if (src_clk == &func_54m_ck)
 869                         val = 3;
 870                 break;
 871         }
 872
 873         if (val == ~0)                  /* Catch errors in offset */
 874                 *type_to_addr = 0;
 875         else
 876                 *type_to_addr = src_reg_addr;
 877         *field_mask = mask;
 878
 879         return val;
 880 }
 881
 882 static int omap2_clk_set_parent(struct clk *clk, struct clk *new_parent)
 883 {
 884         void __iomem * reg;
 885         u32 src_sel, src_off, field_val, field_mask, reg_val, rate;
 886         int ret = -EINVAL;
 887
 888         if (unlikely(clk->flags & CONFIG_PARTICIPANT))
 889                 return ret;
 890
 891         if (clk->flags & SRC_SEL_MASK) {        /* On-chip SEL collection */
 892                 src_sel = (SRC_RATE_SEL_MASK & clk->flags);
 893                 src_off = clk->src_offset;
 894
 895                 if (src_sel == 0)
 896                         goto set_parent_error;
 897
 898                 field_val = omap2_get_src_field(&src_sel, src_off, new_parent,
 899                                                 &field_mask);
 900
 901                 reg = (void __iomem *)src_sel;
 902
 903                 if (clk->usecount > 0)
 904                         _omap2_clk_disable(clk);
 905
 906                 /* Set new source value (previous dividers if any in effect) */
 907                 reg_val = __raw_readl(reg) & ~(field_mask << src_off);
 908                 reg_val |= (field_val << src_off);
 909                 __raw_writel(reg_val, reg);
 910                 wmb();
 911
 912                 if (clk->flags & DELAYED_APP) {
 913                         __raw_writel(0x1, (void __iomem *)&PRCM_CLKCFG_CTRL);
 914                         wmb();
 915                 }
 916                 if (clk->usecount > 0)
 917                         _omap2_clk_enable(clk);
 918
 919                 clk->parent = new_parent;
 920
 921                 /* SRC_RATE_SEL_MASK clocks follow their parents rates.*/
 922                 if ((new_parent == &core_ck) && (clk == &dss1_fck))
 923                         clk->rate = new_parent->rate / 0x10;
 924                 else
 925                         clk->rate = new_parent->rate;
 926
 927                 if (unlikely(clk->flags & RATE_PROPAGATES))
 928                         propagate_rate(clk);
 929
 930                 return 0;
 931         } else {
 932                 clk->parent = new_parent;
 933                 rate = new_parent->rate;
 934                 omap2_clk_set_rate(clk, rate);
 935                 ret = 0;
 936         }
 937
 938  set_parent_error:
 939         return ret;
 940 }
 941
 942 /* Sets basic clocks based on the specified rate */
 943 static int omap2_select_table_rate(struct clk * clk, unsigned long rate)
 944 {
 945         u32 flags, cur_rate, done_rate, bypass = 0;
 946         u8 cpu_mask = 0;
 947         struct prcm_config *prcm;
 948         unsigned long found_speed = 0;
 949
 950         if (clk != &virt_prcm_set)
 951                 return -EINVAL;
 952
 953         /* FIXME: Change cpu_is_omap2420() to cpu_is_omap242x() */
 954         if (cpu_is_omap2420())
 955                 cpu_mask = RATE_IN_242X;
 956         else if (cpu_is_omap2430())
 957                 cpu_mask = RATE_IN_243X;
 958
 959         for (prcm = rate_table; prcm->mpu_speed; prcm++) {
 960                 if (!(prcm->flags & cpu_mask))
 961                         continue;
 962
 963                 if (prcm->xtal_speed != sys_ck.rate)
 964                         continue;
 965
 966                 if (prcm->mpu_speed <= rate) {
 967                         found_speed = prcm->mpu_speed;
 968                         break;
 969                 }
 970         }
 971
 972         if (!found_speed) {
 973                 printk(KERN_INFO "Could not set MPU rate to %luMHz\n",
 974          rate / 1000000);
 975                 return -EINVAL;
 976         }
 977
 978         curr_prcm_set = prcm;
 979         cur_rate = omap2_get_dpll_rate(&dpll_ck);
 980
 981         if (prcm->dpll_speed == cur_rate / 2) {
 982                 omap2_reprogram_sdrc(PRCM_HALF_SPEED, 1);
 983         } else if (prcm->dpll_speed == cur_rate * 2) {
 984                 omap2_reprogram_sdrc(PRCM_FULL_SPEED, 1);
 985         } else if (prcm->dpll_speed != cur_rate) {
 986                 local_irq_save(flags);
 987
 988                 if (prcm->dpll_speed == prcm->xtal_speed)
 989                         bypass = 1;
 990
 991                 if ((prcm->cm_clksel2_pll & 0x3) == 2)
 992                         done_rate = PRCM_FULL_SPEED;
 993                 else
 994                         done_rate = PRCM_HALF_SPEED;
 995
 996                 /* MPU divider */
 997                 CM_CLKSEL_MPU = prcm->cm_clksel_mpu;
 998
 999                 /* dsp + iva1 div(2420), iva2.1(2430) */
1000                 CM_CLKSEL_DSP = prcm->cm_clksel_dsp;
1001
1002                 CM_CLKSEL_GFX = prcm->cm_clksel_gfx;
1003
1004                 /* Major subsystem dividers */
1005                 CM_CLKSEL1_CORE = prcm->cm_clksel1_core;
1006                 if (cpu_is_omap2430())
1007                         CM_CLKSEL_MDM = prcm->cm_clksel_mdm;
1008
1009                 /* x2 to enter init_mem */
1010                 omap2_reprogram_sdrc(PRCM_FULL_SPEED, 1);
1011
1012                 omap2_set_prcm(prcm->cm_clksel1_pll, prcm->base_sdrc_rfr,
1013                                bypass);
1014
1015                 omap2_init_memory_params(omap2_dll_force_needed());
1016                 omap2_reprogram_sdrc(done_rate, 0);
1017
1018                 local_irq_restore(flags);
1019         }
1020         omap2_clksel_recalc(&dpll_ck);
1021
1022         return 0;
1023 }
1024
1025 /*-------------------------------------------------------------------------
1026  * Omap2 clock reset and init functions
1027  *-------------------------------------------------------------------------*/
1028
1029 #ifdef CONFIG_OMAP_RESET_CLOCKS
1030 static void __init omap2_clk_disable_unused(struct clk *clk)
1031 {
1032         u32 regval32;
1033
1034         regval32 = __raw_readl(clk->enable_reg);
1035         if ((regval32 & (1 << clk->enable_bit)) == 0)
1036                 return;
1037
1038         printk(KERN_INFO "Disabling unused clock \"%s\"\n", clk->name);
1039         _omap2_clk_disable(clk);
1040 }
1041 #else
1042 #define omap2_clk_disable_unused        NULL
1043 #endif
1044
1045 static struct clk_functions omap2_clk_functions = {
1046         .clk_enable             = omap2_clk_enable,
1047         .clk_disable            = omap2_clk_disable,
1048         .clk_round_rate         = omap2_clk_round_rate,
1049         .clk_set_rate           = omap2_clk_set_rate,
1050         .clk_set_parent         = omap2_clk_set_parent,
1051         .clk_disable_unused     = omap2_clk_disable_unused,
1052 };
1053
1054 static void __init omap2_get_crystal_rate(struct clk *osc, struct clk *sys)
1055 {
1056         u32 div, aplls, sclk = 13000000;
1057
1058         aplls = CM_CLKSEL1_PLL;
1059         aplls &= ((1 << 23) | (1 << 24) | (1 << 25));
1060         aplls >>= 23;                   /* Isolate field, 0,2,3 */
1061
1062         if (aplls == 0)
1063                 sclk = 19200000;
1064         else if (aplls == 2)
1065                 sclk = 13000000;
1066         else if (aplls == 3)
1067                 sclk = 12000000;
1068
1069         div = PRCM_CLKSRC_CTRL;
1070         div &= ((1 << 7) | (1 << 6));
1071         div >>= sys->rate_offset;
1072
1073         osc->rate = sclk * div;
1074         sys->rate = sclk;
1075 }
1076
1077 /*
1078  * Set clocks for bypass mode for reboot to work.
1079  */
1080 void omap2_clk_prepare_for_reboot(void)
1081 {
1082         u32 rate;
1083
1084         if (vclk == NULL || sclk == NULL)
1085                 return;
1086
1087         rate = clk_get_rate(sclk);
1088         clk_set_rate(vclk, rate);
1089 }
1090
1091 /*
1092  * Switch the MPU rate if specified on cmdline.
1093  * We cannot do this early until cmdline is parsed.
1094  */
1095 static int __init omap2_clk_arch_init(void)
1096 {
1097         if (!mpurate)
1098                 return -EINVAL;
1099
1100         if (omap2_select_table_rate(&virt_prcm_set, mpurate))
1101                 printk(KERN_ERR "Could not find matching MPU rate\n");
1102
1103         propagate_rate(&osc_ck);                /* update main root fast */
1104         propagate_rate(&func_32k_ck);           /* update main root slow */
1105
1106         printk(KERN_INFO "Switched to new clocking rate (Crystal/DPLL/MPU): "
1107                "%ld.%01ld/%ld/%ld MHz\n",
1108                (sys_ck.rate / 1000000), (sys_ck.rate / 100000) % 10,
1109                (dpll_ck.rate / 1000000), (mpu_ck.rate / 1000000)) ;
1110
1111         return 0;
1112 }
1113 arch_initcall(omap2_clk_arch_init);
1114
1115 int __init omap2_clk_init(void)
1116 {
1117         struct prcm_config *prcm;
1118         struct clk ** clkp;
1119         u32 clkrate;
1120
1121         clk_init(&omap2_clk_functions);
1122         omap2_get_crystal_rate(&osc_ck, &sys_ck);
1123
1124         for (clkp = onchip_clks; clkp < onchip_clks + ARRAY_SIZE(onchip_clks);
1125              clkp++) {
1126
1127                 if ((*clkp)->flags & CLOCK_IN_OMAP242X && cpu_is_omap2420()) {
1128                         clk_register(*clkp);
1129                         continue;
1130                 }
1131
1132                 if ((*clkp)->flags & CLOCK_IN_OMAP243X && cpu_is_omap2430()) {
1133                         clk_register(*clkp);
1134                         continue;
1135                 }
1136         }
1137
1138         /* Check the MPU rate set by bootloader */
1139         clkrate = omap2_get_dpll_rate(&dpll_ck);
1140         for (prcm = rate_table; prcm->mpu_speed; prcm++) {
1141                 if (prcm->xtal_speed != sys_ck.rate)
1142                         continue;
1143                 if (prcm->dpll_speed <= clkrate)
1144                          break;
1145         }
1146         curr_prcm_set = prcm;
1147
1148         propagate_rate(&osc_ck);                /* update main root fast */
1149         propagate_rate(&func_32k_ck);           /* update main root slow */
1150
1151         printk(KERN_INFO "Clocking rate (Crystal/DPLL/MPU): "
1152                "%ld.%01ld/%ld/%ld MHz\n",
1153                (sys_ck.rate / 1000000), (sys_ck.rate / 100000) % 10,
1154                (dpll_ck.rate / 1000000), (mpu_ck.rate / 1000000)) ;
1155
1156         /*
1157          * Only enable those clocks we will need, let the drivers
1158          * enable other clocks as necessary
1159          */
1160         clk_enable(&sync_32k_ick);
1161         clk_enable(&omapctrl_ick);
1162
1163         /* Force the APLLs always active. The clocks are idled
1164          * automatically by hardware. */
1165         clk_enable(&apll96_ck);
1166         clk_enable(&apll54_ck);
1167
1168         if (cpu_is_omap2430())
1169                 clk_enable(&sdrc_ick);
1170
1171         /* Avoid sleeping sleeping during omap2_clk_prepare_for_reboot() */
1172         vclk = clk_get(NULL, "virt_prcm_set");
1173         sclk = clk_get(NULL, "sys_ck");
1174
1175         return 0;
1176 }