arch/arm/mach-imx/clock-imx1.c

   1 /*
   2  *  Copyright (C) 2008 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/init.h>
  20 #include <linux/list.h>
  21 #include <linux/math64.h>
  22 #include <linux/err.h>
  23 #include <linux/clk.h>
  24 #include <linux/io.h>
  25 #include <linux/clkdev.h>
  26
  27 #include <mach/clock.h>
  28 #include <mach/hardware.h>
  29 #include <mach/common.h>
  30
  31 #define IO_ADDR_CCM(off)        (MX1_IO_ADDRESS(MX1_CCM_BASE_ADDR + (off)))
  32
  33 /* CCM register addresses */
  34 #define CCM_CSCR        IO_ADDR_CCM(0x0)
  35 #define CCM_MPCTL0      IO_ADDR_CCM(0x4)
  36 #define CCM_SPCTL0      IO_ADDR_CCM(0xc)
  37 #define CCM_PCDR        IO_ADDR_CCM(0x20)
  38
  39 #define CCM_CSCR_CLKO_OFFSET    29
  40 #define CCM_CSCR_CLKO_MASK      (0x7 << 29)
  41 #define CCM_CSCR_USB_OFFSET     26
  42 #define CCM_CSCR_USB_MASK       (0x7 << 26)
  43 #define CCM_CSCR_OSC_EN_SHIFT   17
  44 #define CCM_CSCR_SYSTEM_SEL     (1 << 16)
  45 #define CCM_CSCR_BCLK_OFFSET    10
  46 #define CCM_CSCR_BCLK_MASK      (0xf << 10)
  47 #define CCM_CSCR_PRESC          (1 << 15)
  48
  49 #define CCM_PCDR_PCLK3_OFFSET   16
  50 #define CCM_PCDR_PCLK3_MASK     (0x7f << 16)
  51 #define CCM_PCDR_PCLK2_OFFSET   4
  52 #define CCM_PCDR_PCLK2_MASK     (0xf << 4)
  53 #define CCM_PCDR_PCLK1_OFFSET   0
  54 #define CCM_PCDR_PCLK1_MASK     0xf
  55
  56 #define IO_ADDR_SCM(off)        (MX1_IO_ADDRESS(MX1_SCM_BASE_ADDR + (off)))
  57
  58 /* SCM register addresses */
  59 #define SCM_GCCR        IO_ADDR_SCM(0xc)
  60
  61 #define SCM_GCCR_DMA_CLK_EN_OFFSET      3
  62 #define SCM_GCCR_CSI_CLK_EN_OFFSET      2
  63 #define SCM_GCCR_MMA_CLK_EN_OFFSET      1
  64 #define SCM_GCCR_USBD_CLK_EN_OFFSET     0
  65
  66 static int _clk_enable(struct clk *clk)
  67 {
  68         unsigned int reg;
  69
  70         reg = __raw_readl(clk->enable_reg);
  71         reg |= 1 << clk->enable_shift;
  72         __raw_writel(reg, clk->enable_reg);
  73
  74         return 0;
  75 }
  76
  77 static void _clk_disable(struct clk *clk)
  78 {
  79         unsigned int reg;
  80
  81         reg = __raw_readl(clk->enable_reg);
  82         reg &= ~(1 << clk->enable_shift);
  83         __raw_writel(reg, clk->enable_reg);
  84 }
  85
  86 static int _clk_can_use_parent(const struct clk *clk_arr[], unsigned int size,
  87                                struct clk *parent)
  88 {
  89         int i;
  90
  91         for (i = 0; i < size; i++)
  92                 if (parent == clk_arr[i])
  93                         return i;
  94
  95         return -EINVAL;
  96 }
  97
  98 static unsigned long
  99 _clk_simple_round_rate(struct clk *clk, unsigned long rate, unsigned int limit)
 100 {
 101         int div;
 102         unsigned long parent_rate;
 103
 104         parent_rate = clk_get_rate(clk->parent);
 105
 106         div = parent_rate / rate;
 107         if (parent_rate % rate)
 108                 div++;
 109
 110         if (div > limit)
 111                 div = limit;
 112
 113         return parent_rate / div;
 114 }
 115
 116 static unsigned long _clk_parent_round_rate(struct clk *clk, unsigned long rate)
 117 {
 118         return clk->parent->round_rate(clk->parent, rate);
 119 }
 120
 121 static int _clk_parent_set_rate(struct clk *clk, unsigned long rate)
 122 {
 123         return clk->parent->set_rate(clk->parent, rate);
 124 }
 125
 126 static unsigned long clk16m_get_rate(struct clk *clk)
 127 {
 128         return 16000000;
 129 }
 130
 131 static struct clk clk16m = {
 132         .get_rate = clk16m_get_rate,
 133         .enable = _clk_enable,
 134         .enable_reg = CCM_CSCR,
 135         .enable_shift = CCM_CSCR_OSC_EN_SHIFT,
 136         .disable = _clk_disable,
 137 };
 138
 139 /* in Hz */
 140 static unsigned long clk32_rate;
 141
 142 static unsigned long clk32_get_rate(struct clk *clk)
 143 {
 144         return clk32_rate;
 145 }
 146
 147 static struct clk clk32 = {
 148         .get_rate = clk32_get_rate,
 149 };
 150
 151 static unsigned long clk32_premult_get_rate(struct clk *clk)
 152 {
 153         return clk_get_rate(clk->parent) * 512;
 154 }
 155
 156 static struct clk clk32_premult = {
 157         .parent = &clk32,
 158         .get_rate = clk32_premult_get_rate,
 159 };
 160
 161 static const struct clk *prem_clk_clocks[] = {
 162         &clk32_premult,
 163         &clk16m,
 164 };
 165
 166 static int prem_clk_set_parent(struct clk *clk, struct clk *parent)
 167 {
 168         int i;
 169         unsigned int reg = __raw_readl(CCM_CSCR);
 170
 171         i = _clk_can_use_parent(prem_clk_clocks, ARRAY_SIZE(prem_clk_clocks),
 172                                 parent);
 173
 174         switch (i) {
 175         case 0:
 176                 reg &= ~CCM_CSCR_SYSTEM_SEL;
 177                 break;
 178         case 1:
 179                 reg |= CCM_CSCR_SYSTEM_SEL;
 180                 break;
 181         default:
 182                 return i;
 183         }
 184
 185         __raw_writel(reg, CCM_CSCR);
 186
 187         return 0;
 188 }
 189
 190 static struct clk prem_clk = {
 191         .set_parent = prem_clk_set_parent,
 192 };
 193
 194 static unsigned long system_clk_get_rate(struct clk *clk)
 195 {
 196         return mxc_decode_pll(__raw_readl(CCM_SPCTL0),
 197                               clk_get_rate(clk->parent));
 198 }
 199
 200 static struct clk system_clk = {
 201         .parent = &prem_clk,
 202         .get_rate = system_clk_get_rate,
 203 };
 204
 205 static unsigned long mcu_clk_get_rate(struct clk *clk)
 206 {
 207         return mxc_decode_pll(__raw_readl(CCM_MPCTL0),
 208                               clk_get_rate(clk->parent));
 209 }
 210
 211 static struct clk mcu_clk = {
 212         .parent = &clk32_premult,
 213         .get_rate = mcu_clk_get_rate,
 214 };
 215
 216 static unsigned long fclk_get_rate(struct clk *clk)
 217 {
 218         unsigned long fclk = clk_get_rate(clk->parent);
 219
 220         if (__raw_readl(CCM_CSCR) & CCM_CSCR_PRESC)
 221                 fclk /= 2;
 222
 223         return fclk;
 224 }
 225
 226 static struct clk fclk = {
 227         .parent = &mcu_clk,
 228         .get_rate = fclk_get_rate,
 229 };
 230
 231 /*
 232  *  get hclk ( SDRAM, CSI, Memory Stick, I2C, DMA )
 233  */
 234 static unsigned long hclk_get_rate(struct clk *clk)
 235 {
 236         return clk_get_rate(clk->parent) / (((__raw_readl(CCM_CSCR) &
 237                         CCM_CSCR_BCLK_MASK) >> CCM_CSCR_BCLK_OFFSET) + 1);
 238 }
 239
 240 static unsigned long hclk_round_rate(struct clk *clk, unsigned long rate)
 241 {
 242         return _clk_simple_round_rate(clk, rate, 16);
 243 }
 244
 245 static int hclk_set_rate(struct clk *clk, unsigned long rate)
 246 {
 247         unsigned int div;
 248         unsigned int reg;
 249         unsigned long parent_rate;
 250
 251         parent_rate = clk_get_rate(clk->parent);
 252
 253         div = parent_rate / rate;
 254
 255         if (div > 16 || div < 1 || ((parent_rate / div) != rate))
 256                 return -EINVAL;
 257
 258         div--;
 259
 260         reg = __raw_readl(CCM_CSCR);
 261         reg &= ~CCM_CSCR_BCLK_MASK;
 262         reg |= div << CCM_CSCR_BCLK_OFFSET;
 263         __raw_writel(reg, CCM_CSCR);
 264
 265         return 0;
 266 }
 267
 268 static struct clk hclk = {
 269         .parent = &system_clk,
 270         .get_rate = hclk_get_rate,
 271         .round_rate = hclk_round_rate,
 272         .set_rate = hclk_set_rate,
 273 };
 274
 275 static unsigned long clk48m_get_rate(struct clk *clk)
 276 {
 277         return clk_get_rate(clk->parent) / (((__raw_readl(CCM_CSCR) &
 278                         CCM_CSCR_USB_MASK) >> CCM_CSCR_USB_OFFSET) + 1);
 279 }
 280
 281 static unsigned long clk48m_round_rate(struct clk *clk, unsigned long rate)
 282 {
 283         return _clk_simple_round_rate(clk, rate, 8);
 284 }
 285
 286 static int clk48m_set_rate(struct clk *clk, unsigned long rate)
 287 {
 288         unsigned int div;
 289         unsigned int reg;
 290         unsigned long parent_rate;
 291
 292         parent_rate = clk_get_rate(clk->parent);
 293
 294         div = parent_rate / rate;
 295
 296         if (div > 8 || div < 1 || ((parent_rate / div) != rate))
 297                 return -EINVAL;
 298
 299         div--;
 300
 301         reg = __raw_readl(CCM_CSCR);
 302         reg &= ~CCM_CSCR_USB_MASK;
 303         reg |= div << CCM_CSCR_USB_OFFSET;
 304         __raw_writel(reg, CCM_CSCR);
 305
 306         return 0;
 307 }
 308
 309 static struct clk clk48m = {
 310         .parent = &system_clk,
 311         .get_rate = clk48m_get_rate,
 312         .round_rate = clk48m_round_rate,
 313         .set_rate = clk48m_set_rate,
 314 };
 315
 316 /*
 317  *  get peripheral clock 1 ( UART[12], Timer[12], PWM )
 318  */
 319 static unsigned long perclk1_get_rate(struct clk *clk)
 320 {
 321         return clk_get_rate(clk->parent) / (((__raw_readl(CCM_PCDR) &
 322                         CCM_PCDR_PCLK1_MASK) >> CCM_PCDR_PCLK1_OFFSET) + 1);
 323 }
 324
 325 static unsigned long perclk1_round_rate(struct clk *clk, unsigned long rate)
 326 {
 327         return _clk_simple_round_rate(clk, rate, 16);
 328 }
 329
 330 static int perclk1_set_rate(struct clk *clk, unsigned long rate)
 331 {
 332         unsigned int div;
 333         unsigned int reg;
 334         unsigned long parent_rate;
 335
 336         parent_rate = clk_get_rate(clk->parent);
 337
 338         div = parent_rate / rate;
 339
 340         if (div > 16 || div < 1 || ((parent_rate / div) != rate))
 341                 return -EINVAL;
 342
 343         div--;
 344
 345         reg = __raw_readl(CCM_PCDR);
 346         reg &= ~CCM_PCDR_PCLK1_MASK;
 347         reg |= div << CCM_PCDR_PCLK1_OFFSET;
 348         __raw_writel(reg, CCM_PCDR);
 349
 350         return 0;
 351 }
 352
 353 /*
 354  *  get peripheral clock 2 ( LCD, SD, SPI[12] )
 355  */
 356 static unsigned long perclk2_get_rate(struct clk *clk)
 357 {
 358         return clk_get_rate(clk->parent) / (((__raw_readl(CCM_PCDR) &
 359                         CCM_PCDR_PCLK2_MASK) >> CCM_PCDR_PCLK2_OFFSET) + 1);
 360 }
 361
 362 static unsigned long perclk2_round_rate(struct clk *clk, unsigned long rate)
 363 {
 364         return _clk_simple_round_rate(clk, rate, 16);
 365 }
 366
 367 static int perclk2_set_rate(struct clk *clk, unsigned long rate)
 368 {
 369         unsigned int div;
 370         unsigned int reg;
 371         unsigned long parent_rate;
 372
 373         parent_rate = clk_get_rate(clk->parent);
 374
 375         div = parent_rate / rate;
 376
 377         if (div > 16 || div < 1 || ((parent_rate / div) != rate))
 378                 return -EINVAL;
 379
 380         div--;
 381
 382         reg = __raw_readl(CCM_PCDR);
 383         reg &= ~CCM_PCDR_PCLK2_MASK;
 384         reg |= div << CCM_PCDR_PCLK2_OFFSET;
 385         __raw_writel(reg, CCM_PCDR);
 386
 387         return 0;
 388 }
 389
 390 /*
 391  *  get peripheral clock 3 ( SSI )
 392  */
 393 static unsigned long perclk3_get_rate(struct clk *clk)
 394 {
 395         return clk_get_rate(clk->parent) / (((__raw_readl(CCM_PCDR) &
 396                         CCM_PCDR_PCLK3_MASK) >> CCM_PCDR_PCLK3_OFFSET) + 1);
 397 }
 398
 399 static unsigned long perclk3_round_rate(struct clk *clk, unsigned long rate)
 400 {
 401         return _clk_simple_round_rate(clk, rate, 128);
 402 }
 403
 404 static int perclk3_set_rate(struct clk *clk, unsigned long rate)
 405 {
 406         unsigned int div;
 407         unsigned int reg;
 408         unsigned long parent_rate;
 409
 410         parent_rate = clk_get_rate(clk->parent);
 411
 412         div = parent_rate / rate;
 413
 414         if (div > 128 || div < 1 || ((parent_rate / div) != rate))
 415                 return -EINVAL;
 416
 417         div--;
 418
 419         reg = __raw_readl(CCM_PCDR);
 420         reg &= ~CCM_PCDR_PCLK3_MASK;
 421         reg |= div << CCM_PCDR_PCLK3_OFFSET;
 422         __raw_writel(reg, CCM_PCDR);
 423
 424         return 0;
 425 }
 426
 427 static struct clk perclk[] = {
 428         {
 429                 .id = 0,
 430                 .parent = &system_clk,
 431                 .get_rate = perclk1_get_rate,
 432                 .round_rate = perclk1_round_rate,
 433                 .set_rate = perclk1_set_rate,
 434         }, {
 435                 .id = 1,
 436                 .parent = &system_clk,
 437                 .get_rate = perclk2_get_rate,
 438                 .round_rate = perclk2_round_rate,
 439                 .set_rate = perclk2_set_rate,
 440         }, {
 441                 .id = 2,
 442                 .parent = &system_clk,
 443                 .get_rate = perclk3_get_rate,
 444                 .round_rate = perclk3_round_rate,
 445                 .set_rate = perclk3_set_rate,
 446         }
 447 };
 448
 449 static const struct clk *clko_clocks[] = {
 450         &perclk[0],
 451         &hclk,
 452         &clk48m,
 453         &clk16m,
 454         &prem_clk,
 455         &fclk,
 456 };
 457
 458 static int clko_set_parent(struct clk *clk, struct clk *parent)
 459 {
 460         int i;
 461         unsigned int reg;
 462
 463         i = _clk_can_use_parent(clko_clocks, ARRAY_SIZE(clko_clocks), parent);
 464         if (i < 0)
 465                 return i;
 466
 467         reg = __raw_readl(CCM_CSCR) & ~CCM_CSCR_CLKO_MASK;
 468         reg |= i << CCM_CSCR_CLKO_OFFSET;
 469         __raw_writel(reg, CCM_CSCR);
 470
 471         if (clko_clocks[i]->set_rate && clko_clocks[i]->round_rate) {
 472                 clk->set_rate = _clk_parent_set_rate;
 473                 clk->round_rate = _clk_parent_round_rate;
 474         } else {
 475                 clk->set_rate = NULL;
 476                 clk->round_rate = NULL;
 477         }
 478
 479         return 0;
 480 }
 481
 482 static struct clk clko_clk = {
 483         .set_parent = clko_set_parent,
 484 };
 485
 486 static struct clk dma_clk = {
 487         .parent = &hclk,
 488         .round_rate = _clk_parent_round_rate,
 489         .set_rate = _clk_parent_set_rate,
 490         .enable = _clk_enable,
 491         .enable_reg = SCM_GCCR,
 492         .enable_shift = SCM_GCCR_DMA_CLK_EN_OFFSET,
 493         .disable = _clk_disable,
 494 };
 495
 496 static struct clk csi_clk = {
 497         .parent = &hclk,
 498         .round_rate = _clk_parent_round_rate,
 499         .set_rate = _clk_parent_set_rate,
 500         .enable = _clk_enable,
 501         .enable_reg = SCM_GCCR,
 502         .enable_shift = SCM_GCCR_CSI_CLK_EN_OFFSET,
 503         .disable = _clk_disable,
 504 };
 505
 506 static struct clk mma_clk = {
 507         .parent = &hclk,
 508         .round_rate = _clk_parent_round_rate,
 509         .set_rate = _clk_parent_set_rate,
 510         .enable = _clk_enable,
 511         .enable_reg = SCM_GCCR,
 512         .enable_shift = SCM_GCCR_MMA_CLK_EN_OFFSET,
 513         .disable = _clk_disable,
 514 };
 515
 516 static struct clk usbd_clk = {
 517         .parent = &clk48m,
 518         .round_rate = _clk_parent_round_rate,
 519         .set_rate = _clk_parent_set_rate,
 520         .enable = _clk_enable,
 521         .enable_reg = SCM_GCCR,
 522         .enable_shift = SCM_GCCR_USBD_CLK_EN_OFFSET,
 523         .disable = _clk_disable,
 524 };
 525
 526 static struct clk gpt_clk = {
 527         .parent = &perclk[0],
 528         .round_rate = _clk_parent_round_rate,
 529         .set_rate = _clk_parent_set_rate,
 530 };
 531
 532 static struct clk uart_clk = {
 533         .parent = &perclk[0],
 534         .round_rate = _clk_parent_round_rate,
 535         .set_rate = _clk_parent_set_rate,
 536 };
 537
 538 static struct clk i2c_clk = {
 539         .parent = &hclk,
 540         .round_rate = _clk_parent_round_rate,
 541         .set_rate = _clk_parent_set_rate,
 542 };
 543
 544 static struct clk spi_clk = {
 545         .parent = &perclk[1],
 546         .round_rate = _clk_parent_round_rate,
 547         .set_rate = _clk_parent_set_rate,
 548 };
 549
 550 static struct clk sdhc_clk = {
 551         .parent = &perclk[1],
 552         .round_rate = _clk_parent_round_rate,
 553         .set_rate = _clk_parent_set_rate,
 554 };
 555
 556 static struct clk lcdc_clk = {
 557         .parent = &perclk[1],
 558         .round_rate = _clk_parent_round_rate,
 559         .set_rate = _clk_parent_set_rate,
 560 };
 561
 562 static struct clk mshc_clk = {
 563         .parent = &hclk,
 564         .round_rate = _clk_parent_round_rate,
 565         .set_rate = _clk_parent_set_rate,
 566 };
 567
 568 static struct clk ssi_clk = {
 569         .parent = &perclk[2],
 570         .round_rate = _clk_parent_round_rate,
 571         .set_rate = _clk_parent_set_rate,
 572 };
 573
 574 static struct clk rtc_clk = {
 575         .parent = &clk32,
 576 };
 577
 578 #define _REGISTER_CLOCK(d, n, c) \
 579         { \
 580                 .dev_id = d, \
 581                 .con_id = n, \
 582                 .clk = &c, \
 583         },
 584 static struct clk_lookup lookups[] __initdata = {
 585         _REGISTER_CLOCK(NULL, "dma", dma_clk)
 586         _REGISTER_CLOCK("mx1-camera.0", NULL, csi_clk)
 587         _REGISTER_CLOCK(NULL, "mma", mma_clk)
 588         _REGISTER_CLOCK("imx_udc.0", NULL, usbd_clk)
 589         _REGISTER_CLOCK(NULL, "gpt", gpt_clk)
 590         _REGISTER_CLOCK("imx-uart.0", NULL, uart_clk)
 591         _REGISTER_CLOCK("imx-uart.1", NULL, uart_clk)
 592         _REGISTER_CLOCK("imx-uart.2", NULL, uart_clk)
 593         _REGISTER_CLOCK("imx-i2c.0", NULL, i2c_clk)
 594         _REGISTER_CLOCK("imx1-cspi.0", NULL, spi_clk)
 595         _REGISTER_CLOCK("imx1-cspi.1", NULL, spi_clk)
 596         _REGISTER_CLOCK("imx-mmc.0", NULL, sdhc_clk)
 597         _REGISTER_CLOCK("imx-fb.0", NULL, lcdc_clk)
 598         _REGISTER_CLOCK(NULL, "mshc", mshc_clk)
 599         _REGISTER_CLOCK(NULL, "ssi", ssi_clk)
 600         _REGISTER_CLOCK("mxc_rtc.0", NULL, rtc_clk)
 601 };
 602
 603 int __init mx1_clocks_init(unsigned long fref)
 604 {
 605         unsigned int reg;
 606
 607         /* disable clocks we are able to */
 608         __raw_writel(0, SCM_GCCR);
 609
 610         clk32_rate = fref;
 611         reg = __raw_readl(CCM_CSCR);
 612
 613         /* detect clock reference for system PLL */
 614         if (reg & CCM_CSCR_SYSTEM_SEL) {
 615                 prem_clk.parent = &clk16m;
 616         } else {
 617                 /* ensure that oscillator is disabled */
 618                 reg &= ~(1 << CCM_CSCR_OSC_EN_SHIFT);
 619                 __raw_writel(reg, CCM_CSCR);
 620                 prem_clk.parent = &clk32_premult;
 621         }
 622
 623         /* detect reference for CLKO */
 624         reg = (reg & CCM_CSCR_CLKO_MASK) >> CCM_CSCR_CLKO_OFFSET;
 625         clko_clk.parent = (struct clk *)clko_clocks[reg];
 626
 627         clkdev_add_table(lookups, ARRAY_SIZE(lookups));
 628
 629         clk_enable(&hclk);
 630         clk_enable(&fclk);
 631
 632         mxc_timer_init(&gpt_clk, MX1_IO_ADDRESS(MX1_TIM1_BASE_ADDR),
 633                         MX1_TIM1_INT);
 634
 635         return 0;
 636 }