err.no Git - linux-2.6/blob - arch/arm/mach-s3c2412/clock.c

   1 /* linux/arch/arm/mach-s3c2412/clock.c
   2  *
   3  * Copyright (c) 2006 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * S3C2412,S3C2413 Clock control support
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21 */
  22
  23 #include <linux/init.h>
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/list.h>
  27 #include <linux/errno.h>
  28 #include <linux/err.h>
  29 #include <linux/sysdev.h>
  30 #include <linux/clk.h>
  31 #include <linux/mutex.h>
  32 #include <linux/delay.h>
  33 #include <linux/serial_core.h>
  34
  35 #include <asm/mach/map.h>
  36
  37 #include <mach/hardware.h>
  38 #include <asm/io.h>
  39
  40 #include <asm/plat-s3c/regs-serial.h>
  41 #include <mach/regs-clock.h>
  42 #include <mach/regs-gpio.h>
  43
  44 #include <asm/plat-s3c24xx/s3c2412.h>
  45 #include <asm/plat-s3c24xx/clock.h>
  46 #include <asm/plat-s3c24xx/cpu.h>
  47
  48 /* We currently have to assume that the system is running
  49  * from the XTPll input, and that all ***REFCLKs are being
  50  * fed from it, as we cannot read the state of OM[4] from
  51  * software.
  52  *
  53  * It would be possible for each board initialisation to
  54  * set the correct muxing at initialisation
  55 */
  56
  57 static int s3c2412_clkcon_enable(struct clk *clk, int enable)
  58 {
  59         unsigned int clocks = clk->ctrlbit;
  60         unsigned long clkcon;
  61
  62         clkcon = __raw_readl(S3C2410_CLKCON);
  63
  64         if (enable)
  65                 clkcon |= clocks;
  66         else
  67                 clkcon &= ~clocks;
  68
  69         __raw_writel(clkcon, S3C2410_CLKCON);
  70
  71         return 0;
  72 }
  73
  74 static int s3c2412_upll_enable(struct clk *clk, int enable)
  75 {
  76         unsigned long upllcon = __raw_readl(S3C2410_UPLLCON);
  77         unsigned long orig = upllcon;
  78
  79         if (!enable)
  80                 upllcon |= S3C2412_PLLCON_OFF;
  81         else
  82                 upllcon &= ~S3C2412_PLLCON_OFF;
  83
  84         __raw_writel(upllcon, S3C2410_UPLLCON);
  85
  86         /* allow ~150uS for the PLL to settle and lock */
  87
  88         if (enable && (orig & S3C2412_PLLCON_OFF))
  89                 udelay(150);
  90
  91         return 0;
  92 }
  93
  94 /* clock selections */
  95
  96 /* CPU EXTCLK input */
  97 static struct clk clk_ext = {
  98         .name           = "extclk",
  99         .id             = -1,
 100 };
 101
 102 static struct clk clk_erefclk = {
 103         .name           = "erefclk",
 104         .id             = -1,
 105 };
 106
 107 static struct clk clk_urefclk = {
 108         .name           = "urefclk",
 109         .id             = -1,
 110 };
 111
 112 static int s3c2412_setparent_usysclk(struct clk *clk, struct clk *parent)
 113 {
 114         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
 115
 116         if (parent == &clk_urefclk)
 117                 clksrc &= ~S3C2412_CLKSRC_USYSCLK_UPLL;
 118         else if (parent == &clk_upll)
 119                 clksrc |= S3C2412_CLKSRC_USYSCLK_UPLL;
 120         else
 121                 return -EINVAL;
 122
 123         clk->parent = parent;
 124
 125         __raw_writel(clksrc, S3C2412_CLKSRC);
 126         return 0;
 127 }
 128
 129 static struct clk clk_usysclk = {
 130         .name           = "usysclk",
 131         .id             = -1,
 132         .parent         = &clk_xtal,
 133         .set_parent     = s3c2412_setparent_usysclk,
 134 };
 135
 136 static struct clk clk_mrefclk = {
 137         .name           = "mrefclk",
 138         .parent         = &clk_xtal,
 139         .id             = -1,
 140 };
 141
 142 static struct clk clk_mdivclk = {
 143         .name           = "mdivclk",
 144         .parent         = &clk_xtal,
 145         .id             = -1,
 146 };
 147
 148 static int s3c2412_setparent_usbsrc(struct clk *clk, struct clk *parent)
 149 {
 150         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
 151
 152         if (parent == &clk_usysclk)
 153                 clksrc &= ~S3C2412_CLKSRC_USBCLK_HCLK;
 154         else if (parent == &clk_h)
 155                 clksrc |= S3C2412_CLKSRC_USBCLK_HCLK;
 156         else
 157                 return -EINVAL;
 158
 159         clk->parent = parent;
 160
 161         __raw_writel(clksrc, S3C2412_CLKSRC);
 162         return 0;
 163 }
 164
 165 static unsigned long s3c2412_roundrate_usbsrc(struct clk *clk,
 166                                               unsigned long rate)
 167 {
 168         unsigned long parent_rate = clk_get_rate(clk->parent);
 169         int div;
 170
 171         if (rate > parent_rate)
 172                 return parent_rate;
 173
 174         div = parent_rate / rate;
 175         if (div > 2)
 176                 div = 2;
 177
 178         return parent_rate / div;
 179 }
 180
 181 static unsigned long s3c2412_getrate_usbsrc(struct clk *clk)
 182 {
 183         unsigned long parent_rate = clk_get_rate(clk->parent);
 184         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
 185
 186         return parent_rate / ((div & S3C2412_CLKDIVN_USB48DIV) ? 2 : 1);
 187 }
 188
 189 static int s3c2412_setrate_usbsrc(struct clk *clk, unsigned long rate)
 190 {
 191         unsigned long parent_rate = clk_get_rate(clk->parent);
 192         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
 193
 194         rate = s3c2412_roundrate_usbsrc(clk, rate);
 195
 196         if ((parent_rate / rate) == 2)
 197                 clkdivn |= S3C2412_CLKDIVN_USB48DIV;
 198         else
 199                 clkdivn &= ~S3C2412_CLKDIVN_USB48DIV;
 200
 201         __raw_writel(clkdivn, S3C2410_CLKDIVN);
 202         return 0;
 203 }
 204
 205 static struct clk clk_usbsrc = {
 206         .name           = "usbsrc",
 207         .id             = -1,
 208         .get_rate       = s3c2412_getrate_usbsrc,
 209         .set_rate       = s3c2412_setrate_usbsrc,
 210         .round_rate     = s3c2412_roundrate_usbsrc,
 211         .set_parent     = s3c2412_setparent_usbsrc,
 212 };
 213
 214 static int s3c2412_setparent_msysclk(struct clk *clk, struct clk *parent)
 215 {
 216         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
 217
 218         if (parent == &clk_mdivclk)
 219                 clksrc &= ~S3C2412_CLKSRC_MSYSCLK_MPLL;
 220         else if (parent == &clk_mpll)
 221                 clksrc |= S3C2412_CLKSRC_MSYSCLK_MPLL;
 222         else
 223                 return -EINVAL;
 224
 225         clk->parent = parent;
 226
 227         __raw_writel(clksrc, S3C2412_CLKSRC);
 228         return 0;
 229 }
 230
 231 static struct clk clk_msysclk = {
 232         .name           = "msysclk",
 233         .id             = -1,
 234         .set_parent     = s3c2412_setparent_msysclk,
 235 };
 236
 237 static int s3c2412_setparent_armclk(struct clk *clk, struct clk *parent)
 238 {
 239         unsigned long flags;
 240         unsigned long clkdiv;
 241         unsigned long dvs;
 242
 243         /* Note, we current equate fclk andf msysclk for S3C2412 */
 244
 245         if (parent == &clk_msysclk || parent == &clk_f)
 246                 dvs = 0;
 247         else if (parent == &clk_h)
 248                 dvs = S3C2412_CLKDIVN_DVSEN;
 249         else
 250                 return -EINVAL;
 251
 252         clk->parent = parent;
 253
 254         /* update this under irq lockdown, clkdivn is not protected
 255          * by the clock system. */
 256
 257         local_irq_save(flags);
 258
 259         clkdiv  = __raw_readl(S3C2410_CLKDIVN);
 260         clkdiv &= ~S3C2412_CLKDIVN_DVSEN;
 261         clkdiv |= dvs;
 262         __raw_writel(clkdiv, S3C2410_CLKDIVN);
 263
 264         local_irq_restore(flags);
 265
 266         return 0;
 267 }
 268
 269 static struct clk clk_armclk = {
 270         .name           = "armclk",
 271         .id             = -1,
 272         .parent         = &clk_msysclk,
 273         .set_parent     = s3c2412_setparent_armclk,
 274 };
 275
 276 /* these next clocks have an divider immediately after them,
 277  * so we can register them with their divider and leave out the
 278  * intermediate clock stage
 279 */
 280 static unsigned long s3c2412_roundrate_clksrc(struct clk *clk,
 281                                               unsigned long rate)
 282 {
 283         unsigned long parent_rate = clk_get_rate(clk->parent);
 284         int div;
 285
 286         if (rate > parent_rate)
 287                 return parent_rate;
 288
 289         /* note, we remove the +/- 1 calculations as they cancel out */
 290
 291         div = (rate / parent_rate);
 292
 293         if (div < 1)
 294                 div = 1;
 295         else if (div > 16)
 296                 div = 16;
 297
 298         return parent_rate / div;
 299 }
 300
 301 static int s3c2412_setparent_uart(struct clk *clk, struct clk *parent)
 302 {
 303         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
 304
 305         if (parent == &clk_erefclk)
 306                 clksrc &= ~S3C2412_CLKSRC_UARTCLK_MPLL;
 307         else if (parent == &clk_mpll)
 308                 clksrc |= S3C2412_CLKSRC_UARTCLK_MPLL;
 309         else
 310                 return -EINVAL;
 311
 312         clk->parent = parent;
 313
 314         __raw_writel(clksrc, S3C2412_CLKSRC);
 315         return 0;
 316 }
 317
 318 static unsigned long s3c2412_getrate_uart(struct clk *clk)
 319 {
 320         unsigned long parent_rate = clk_get_rate(clk->parent);
 321         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
 322
 323         div &= S3C2412_CLKDIVN_UARTDIV_MASK;
 324         div >>= S3C2412_CLKDIVN_UARTDIV_SHIFT;
 325
 326         return parent_rate / (div + 1);
 327 }
 328
 329 static int s3c2412_setrate_uart(struct clk *clk, unsigned long rate)
 330 {
 331         unsigned long parent_rate = clk_get_rate(clk->parent);
 332         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
 333
 334         rate = s3c2412_roundrate_clksrc(clk, rate);
 335
 336         clkdivn &= ~S3C2412_CLKDIVN_UARTDIV_MASK;
 337         clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_UARTDIV_SHIFT;
 338
 339         __raw_writel(clkdivn, S3C2410_CLKDIVN);
 340         return 0;
 341 }
 342
 343 static struct clk clk_uart = {
 344         .name           = "uartclk",
 345         .id             = -1,
 346         .get_rate       = s3c2412_getrate_uart,
 347         .set_rate       = s3c2412_setrate_uart,
 348         .set_parent     = s3c2412_setparent_uart,
 349         .round_rate     = s3c2412_roundrate_clksrc,
 350 };
 351
 352 static int s3c2412_setparent_i2s(struct clk *clk, struct clk *parent)
 353 {
 354         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
 355
 356         if (parent == &clk_erefclk)
 357                 clksrc &= ~S3C2412_CLKSRC_I2SCLK_MPLL;
 358         else if (parent == &clk_mpll)
 359                 clksrc |= S3C2412_CLKSRC_I2SCLK_MPLL;
 360         else
 361                 return -EINVAL;
 362
 363         clk->parent = parent;
 364
 365         __raw_writel(clksrc, S3C2412_CLKSRC);
 366         return 0;
 367 }
 368
 369 static unsigned long s3c2412_getrate_i2s(struct clk *clk)
 370 {
 371         unsigned long parent_rate = clk_get_rate(clk->parent);
 372         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
 373
 374         div &= S3C2412_CLKDIVN_I2SDIV_MASK;
 375         div >>= S3C2412_CLKDIVN_I2SDIV_SHIFT;
 376
 377         return parent_rate / (div + 1);
 378 }
 379
 380 static int s3c2412_setrate_i2s(struct clk *clk, unsigned long rate)
 381 {
 382         unsigned long parent_rate = clk_get_rate(clk->parent);
 383         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
 384
 385         rate = s3c2412_roundrate_clksrc(clk, rate);
 386
 387         clkdivn &= ~S3C2412_CLKDIVN_I2SDIV_MASK;
 388         clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_I2SDIV_SHIFT;
 389
 390         __raw_writel(clkdivn, S3C2410_CLKDIVN);
 391         return 0;
 392 }
 393
 394 static struct clk clk_i2s = {
 395         .name           = "i2sclk",
 396         .id             = -1,
 397         .get_rate       = s3c2412_getrate_i2s,
 398         .set_rate       = s3c2412_setrate_i2s,
 399         .set_parent     = s3c2412_setparent_i2s,
 400         .round_rate     = s3c2412_roundrate_clksrc,
 401 };
 402
 403 static int s3c2412_setparent_cam(struct clk *clk, struct clk *parent)
 404 {
 405         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
 406
 407         if (parent == &clk_usysclk)
 408                 clksrc &= ~S3C2412_CLKSRC_CAMCLK_HCLK;
 409         else if (parent == &clk_h)
 410                 clksrc |= S3C2412_CLKSRC_CAMCLK_HCLK;
 411         else
 412                 return -EINVAL;
 413
 414         clk->parent = parent;
 415
 416         __raw_writel(clksrc, S3C2412_CLKSRC);
 417         return 0;
 418 }
 419 static unsigned long s3c2412_getrate_cam(struct clk *clk)
 420 {
 421         unsigned long parent_rate = clk_get_rate(clk->parent);
 422         unsigned long div = __raw_readl(S3C2410_CLKDIVN);
 423
 424         div &= S3C2412_CLKDIVN_CAMDIV_MASK;
 425         div >>= S3C2412_CLKDIVN_CAMDIV_SHIFT;
 426
 427         return parent_rate / (div + 1);
 428 }
 429
 430 static int s3c2412_setrate_cam(struct clk *clk, unsigned long rate)
 431 {
 432         unsigned long parent_rate = clk_get_rate(clk->parent);
 433         unsigned long clkdivn = __raw_readl(S3C2410_CLKDIVN);
 434
 435         rate = s3c2412_roundrate_clksrc(clk, rate);
 436
 437         clkdivn &= ~S3C2412_CLKDIVN_CAMDIV_MASK;
 438         clkdivn |= ((parent_rate / rate) - 1) << S3C2412_CLKDIVN_CAMDIV_SHIFT;
 439
 440         __raw_writel(clkdivn, S3C2410_CLKDIVN);
 441         return 0;
 442 }
 443
 444 static struct clk clk_cam = {
 445         .name           = "camif-upll", /* same as 2440 name */
 446         .id             = -1,
 447         .get_rate       = s3c2412_getrate_cam,
 448         .set_rate       = s3c2412_setrate_cam,
 449         .set_parent     = s3c2412_setparent_cam,
 450         .round_rate     = s3c2412_roundrate_clksrc,
 451 };
 452
 453 /* standard clock definitions */
 454
 455 static struct clk init_clocks_disable[] = {
 456         {
 457                 .name           = "nand",
 458                 .id             = -1,
 459                 .parent         = &clk_h,
 460                 .enable         = s3c2412_clkcon_enable,
 461                 .ctrlbit        = S3C2412_CLKCON_NAND,
 462         }, {
 463                 .name           = "sdi",
 464                 .id             = -1,
 465                 .parent         = &clk_p,
 466                 .enable         = s3c2412_clkcon_enable,
 467                 .ctrlbit        = S3C2412_CLKCON_SDI,
 468         }, {
 469                 .name           = "adc",
 470                 .id             = -1,
 471                 .parent         = &clk_p,
 472                 .enable         = s3c2412_clkcon_enable,
 473                 .ctrlbit        = S3C2412_CLKCON_ADC,
 474         }, {
 475                 .name           = "i2c",
 476                 .id             = -1,
 477                 .parent         = &clk_p,
 478                 .enable         = s3c2412_clkcon_enable,
 479                 .ctrlbit        = S3C2412_CLKCON_IIC,
 480         }, {
 481                 .name           = "iis",
 482                 .id             = -1,
 483                 .parent         = &clk_p,
 484                 .enable         = s3c2412_clkcon_enable,
 485                 .ctrlbit        = S3C2412_CLKCON_IIS,
 486         }, {
 487                 .name           = "spi",
 488                 .id             = -1,
 489                 .parent         = &clk_p,
 490                 .enable         = s3c2412_clkcon_enable,
 491                 .ctrlbit        = S3C2412_CLKCON_SPI,
 492         }
 493 };
 494
 495 static struct clk init_clocks[] = {
 496         {
 497                 .name           = "dma",
 498                 .id             = 0,
 499                 .parent         = &clk_h,
 500                 .enable         = s3c2412_clkcon_enable,
 501                 .ctrlbit        = S3C2412_CLKCON_DMA0,
 502         }, {
 503                 .name           = "dma",
 504                 .id             = 1,
 505                 .parent         = &clk_h,
 506                 .enable         = s3c2412_clkcon_enable,
 507                 .ctrlbit        = S3C2412_CLKCON_DMA1,
 508         }, {
 509                 .name           = "dma",
 510                 .id             = 2,
 511                 .parent         = &clk_h,
 512                 .enable         = s3c2412_clkcon_enable,
 513                 .ctrlbit        = S3C2412_CLKCON_DMA2,
 514         }, {
 515                 .name           = "dma",
 516                 .id             = 3,
 517                 .parent         = &clk_h,
 518                 .enable         = s3c2412_clkcon_enable,
 519                 .ctrlbit        = S3C2412_CLKCON_DMA3,
 520         }, {
 521                 .name           = "lcd",
 522                 .id             = -1,
 523                 .parent         = &clk_h,
 524                 .enable         = s3c2412_clkcon_enable,
 525                 .ctrlbit        = S3C2412_CLKCON_LCDC,
 526         }, {
 527                 .name           = "gpio",
 528                 .id             = -1,
 529                 .parent         = &clk_p,
 530                 .enable         = s3c2412_clkcon_enable,
 531                 .ctrlbit        = S3C2412_CLKCON_GPIO,
 532         }, {
 533                 .name           = "usb-host",
 534                 .id             = -1,
 535                 .parent         = &clk_h,
 536                 .enable         = s3c2412_clkcon_enable,
 537                 .ctrlbit        = S3C2412_CLKCON_USBH,
 538         }, {
 539                 .name           = "usb-device",
 540                 .id             = -1,
 541                 .parent         = &clk_h,
 542                 .enable         = s3c2412_clkcon_enable,
 543                 .ctrlbit        = S3C2412_CLKCON_USBD,
 544         }, {
 545                 .name           = "timers",
 546                 .id             = -1,
 547                 .parent         = &clk_p,
 548                 .enable         = s3c2412_clkcon_enable,
 549                 .ctrlbit        = S3C2412_CLKCON_PWMT,
 550         }, {
 551                 .name           = "uart",
 552                 .id             = 0,
 553                 .parent         = &clk_p,
 554                 .enable         = s3c2412_clkcon_enable,
 555                 .ctrlbit        = S3C2412_CLKCON_UART0,
 556         }, {
 557                 .name           = "uart",
 558                 .id             = 1,
 559                 .parent         = &clk_p,
 560                 .enable         = s3c2412_clkcon_enable,
 561                 .ctrlbit        = S3C2412_CLKCON_UART1,
 562         }, {
 563                 .name           = "uart",
 564                 .id             = 2,
 565                 .parent         = &clk_p,
 566                 .enable         = s3c2412_clkcon_enable,
 567                 .ctrlbit        = S3C2412_CLKCON_UART2,
 568         }, {
 569                 .name           = "rtc",
 570                 .id             = -1,
 571                 .parent         = &clk_p,
 572                 .enable         = s3c2412_clkcon_enable,
 573                 .ctrlbit        = S3C2412_CLKCON_RTC,
 574         }, {
 575                 .name           = "watchdog",
 576                 .id             = -1,
 577                 .parent         = &clk_p,
 578                 .ctrlbit        = 0,
 579         }, {
 580                 .name           = "usb-bus-gadget",
 581                 .id             = -1,
 582                 .parent         = &clk_usb_bus,
 583                 .enable         = s3c2412_clkcon_enable,
 584                 .ctrlbit        = S3C2412_CLKCON_USB_DEV48,
 585         }, {
 586                 .name           = "usb-bus-host",
 587                 .id             = -1,
 588                 .parent         = &clk_usb_bus,
 589                 .enable         = s3c2412_clkcon_enable,
 590                 .ctrlbit        = S3C2412_CLKCON_USB_HOST48,
 591         }
 592 };
 593
 594 /* clocks to add where we need to check their parentage */
 595
 596 struct clk_init {
 597         struct clk      *clk;
 598         unsigned int     bit;
 599         struct clk      *src_0;
 600         struct clk      *src_1;
 601 };
 602
 603 static struct clk_init clks_src[] __initdata = {
 604         {
 605                 .clk    = &clk_usysclk,
 606                 .bit    = S3C2412_CLKSRC_USBCLK_HCLK,
 607                 .src_0  = &clk_urefclk,
 608                 .src_1  = &clk_upll,
 609         }, {
 610                 .clk    = &clk_i2s,
 611                 .bit    = S3C2412_CLKSRC_I2SCLK_MPLL,
 612                 .src_0  = &clk_erefclk,
 613                 .src_1  = &clk_mpll,
 614         }, {
 615                 .clk    = &clk_cam,
 616                 .bit    = S3C2412_CLKSRC_CAMCLK_HCLK,
 617                 .src_0  = &clk_usysclk,
 618                 .src_1  = &clk_h,
 619         }, {
 620                 .clk    = &clk_msysclk,
 621                 .bit    = S3C2412_CLKSRC_MSYSCLK_MPLL,
 622                 .src_0  = &clk_mdivclk,
 623                 .src_1  = &clk_mpll,
 624         }, {
 625                 .clk    = &clk_uart,
 626                 .bit    = S3C2412_CLKSRC_UARTCLK_MPLL,
 627                 .src_0  = &clk_erefclk,
 628                 .src_1  = &clk_mpll,
 629         }, {
 630                 .clk    = &clk_usbsrc,
 631                 .bit    = S3C2412_CLKSRC_USBCLK_HCLK,
 632                 .src_0  = &clk_usysclk,
 633                 .src_1  = &clk_h,
 634         /* here we assume  OM[4] select xtal */
 635         }, {
 636                 .clk    = &clk_erefclk,
 637                 .bit    = S3C2412_CLKSRC_EREFCLK_EXTCLK,
 638                 .src_0  = &clk_xtal,
 639                 .src_1  = &clk_ext,
 640         }, {
 641                 .clk    = &clk_urefclk,
 642                 .bit    = S3C2412_CLKSRC_UREFCLK_EXTCLK,
 643                 .src_0  = &clk_xtal,
 644                 .src_1  = &clk_ext,
 645         },
 646 };
 647
 648 /* s3c2412_clk_initparents
 649  *
 650  * Initialise the parents for the clocks that we get at start-time
 651 */
 652
 653 static void __init s3c2412_clk_initparents(void)
 654 {
 655         unsigned long clksrc = __raw_readl(S3C2412_CLKSRC);
 656         struct clk_init *cip = clks_src;
 657         struct clk *src;
 658         int ptr;
 659         int ret;
 660
 661         for (ptr = 0; ptr < ARRAY_SIZE(clks_src); ptr++, cip++) {
 662                 ret = s3c24xx_register_clock(cip->clk);
 663                 if (ret < 0) {
 664                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
 665                                cip->clk->name, ret);
 666                 }
 667
 668                 src = (clksrc & cip->bit) ? cip->src_1 : cip->src_0;
 669
 670                 printk(KERN_INFO "%s: parent %s\n", cip->clk->name, src->name);
 671                 clk_set_parent(cip->clk, src);
 672         }
 673 }
 674
 675 /* clocks to add straight away */
 676
 677 static struct clk *clks[] __initdata = {
 678         &clk_ext,
 679         &clk_usb_bus,
 680         &clk_mrefclk,
 681         &clk_armclk,
 682 };
 683
 684 int __init s3c2412_baseclk_add(void)
 685 {
 686         unsigned long clkcon  = __raw_readl(S3C2410_CLKCON);
 687         unsigned int dvs;
 688         struct clk *clkp;
 689         int ret;
 690         int ptr;
 691
 692         clk_upll.enable = s3c2412_upll_enable;
 693         clk_usb_bus.parent = &clk_usbsrc;
 694         clk_usb_bus.rate = 0x0;
 695
 696         clk_f.parent = &clk_msysclk;
 697
 698         s3c2412_clk_initparents();
 699
 700         for (ptr = 0; ptr < ARRAY_SIZE(clks); ptr++) {
 701                 clkp = clks[ptr];
 702
 703                 ret = s3c24xx_register_clock(clkp);
 704                 if (ret < 0) {
 705                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
 706                                clkp->name, ret);
 707                 }
 708         }
 709
 710         /* set the dvs state according to what we got at boot time */
 711
 712         dvs = __raw_readl(S3C2410_CLKDIVN) & S3C2412_CLKDIVN_DVSEN;
 713
 714         if (dvs)
 715                 clk_armclk.parent = &clk_h;
 716
 717         printk(KERN_INFO "S3C2412: DVS is %s\n", dvs ? "on" : "off");
 718
 719         /* ensure usb bus clock is within correct rate of 48MHz */
 720
 721         if (clk_get_rate(&clk_usb_bus) != (48 * 1000 * 1000)) {
 722                 printk(KERN_INFO "Warning: USB bus clock not at 48MHz\n");
 723
 724                 /* for the moment, let's use the UPLL, and see if we can
 725                  * get 48MHz */
 726
 727                 clk_set_parent(&clk_usysclk, &clk_upll);
 728                 clk_set_parent(&clk_usbsrc, &clk_usysclk);
 729                 clk_set_rate(&clk_usbsrc, 48*1000*1000);
 730         }
 731
 732         printk("S3C2412: upll %s, %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
 733                (__raw_readl(S3C2410_UPLLCON) & S3C2412_PLLCON_OFF) ? "off":"on",
 734                print_mhz(clk_get_rate(&clk_upll)),
 735                print_mhz(clk_get_rate(&clk_usb_bus)));
 736
 737         /* register clocks from clock array */
 738
 739         clkp = init_clocks;
 740         for (ptr = 0; ptr < ARRAY_SIZE(init_clocks); ptr++, clkp++) {
 741                 /* ensure that we note the clock state */
 742
 743                 clkp->usage = clkcon & clkp->ctrlbit ? 1 : 0;
 744
 745                 ret = s3c24xx_register_clock(clkp);
 746                 if (ret < 0) {
 747                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
 748                                clkp->name, ret);
 749                 }
 750         }
 751
 752         /* We must be careful disabling the clocks we are not intending to
 753          * be using at boot time, as subsystems such as the LCD which do
 754          * their own DMA requests to the bus can cause the system to lockup
 755          * if they where in the middle of requesting bus access.
 756          *
 757          * Disabling the LCD clock if the LCD is active is very dangerous,
 758          * and therefore the bootloader should be careful to not enable
 759          * the LCD clock if it is not needed.
 760         */
 761
 762         /* install (and disable) the clocks we do not need immediately */
 763
 764         clkp = init_clocks_disable;
 765         for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) {
 766
 767                 ret = s3c24xx_register_clock(clkp);
 768                 if (ret < 0) {
 769                         printk(KERN_ERR "Failed to register clock %s (%d)\n",
 770                                clkp->name, ret);
 771                 }
 772
 773                 s3c2412_clkcon_enable(clkp, 0);
 774         }
 775
 776         return 0;
 777 }