arch/arm/plat-s3c24xx/s3c2443-clock.c

   1 /* linux/arch/arm/plat-s3c24xx/s3c2443-clock.c
   2  *
   3  * Copyright (c) 2007, 2010 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * S3C2443 Clock control suport - common code
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/clk.h>
  11 #include <linux/io.h>
  12
  13 #include <mach/regs-s3c2443-clock.h>
  14
  15 #include <plat/s3c2443.h>
  16 #include <plat/clock.h>
  17 #include <plat/clock-clksrc.h>
  18 #include <plat/cpu.h>
  19
  20 #include <plat/cpu-freq.h>
  21
  22
  23 static int s3c2443_gate(void __iomem *reg, struct clk *clk, int enable)
  24 {
  25         u32 ctrlbit = clk->ctrlbit;
  26         u32 con = __raw_readl(reg);
  27
  28         if (enable)
  29                 con |= ctrlbit;
  30         else
  31                 con &= ~ctrlbit;
  32
  33         __raw_writel(con, reg);
  34         return 0;
  35 }
  36
  37 int s3c2443_clkcon_enable_h(struct clk *clk, int enable)
  38 {
  39         return s3c2443_gate(S3C2443_HCLKCON, clk, enable);
  40 }
  41
  42 int s3c2443_clkcon_enable_p(struct clk *clk, int enable)
  43 {
  44         return s3c2443_gate(S3C2443_PCLKCON, clk, enable);
  45 }
  46
  47 int s3c2443_clkcon_enable_s(struct clk *clk, int enable)
  48 {
  49         return s3c2443_gate(S3C2443_SCLKCON, clk, enable);
  50 }
  51
  52 /* mpllref is a direct descendant of clk_xtal by default, but it is not
  53  * elided as the EPLL can be either sourced by the XTAL or EXTCLK and as
  54  * such directly equating the two source clocks is impossible.
  55  */
  56 struct clk clk_mpllref = {
  57         .name           = "mpllref",
  58         .parent         = &clk_xtal,
  59         .id             = -1,
  60 };
  61
  62 static struct clk *clk_epllref_sources[] = {
  63         [0] = &clk_mpllref,
  64         [1] = &clk_mpllref,
  65         [2] = &clk_xtal,
  66         [3] = &clk_ext,
  67 };
  68
  69 struct clksrc_clk clk_epllref = {
  70         .clk    = {
  71                 .name           = "epllref",
  72                 .id             = -1,
  73         },
  74         .sources = &(struct clksrc_sources) {
  75                 .sources = clk_epllref_sources,
  76                 .nr_sources = ARRAY_SIZE(clk_epllref_sources),
  77         },
  78         .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 7 },
  79 };
  80
  81 /* esysclk
  82  *
  83  * this is sourced from either the EPLL or the EPLLref clock
  84 */
  85
  86 static struct clk *clk_sysclk_sources[] = {
  87         [0] = &clk_epllref.clk,
  88         [1] = &clk_epll,
  89 };
  90
  91 struct clksrc_clk clk_esysclk = {
  92         .clk    = {
  93                 .name           = "esysclk",
  94                 .parent         = &clk_epll,
  95                 .id             = -1,
  96         },
  97         .sources = &(struct clksrc_sources) {
  98                 .sources = clk_sysclk_sources,
  99                 .nr_sources = ARRAY_SIZE(clk_sysclk_sources),
 100         },
 101         .reg_src = { .reg = S3C2443_CLKSRC, .size = 1, .shift = 6 },
 102 };
 103
 104 static unsigned long s3c2443_getrate_mdivclk(struct clk *clk)
 105 {
 106         unsigned long parent_rate = clk_get_rate(clk->parent);
 107         unsigned long div = __raw_readl(S3C2443_CLKDIV0);
 108
 109         div  &= S3C2443_CLKDIV0_EXTDIV_MASK;
 110         div >>= (S3C2443_CLKDIV0_EXTDIV_SHIFT-1);       /* x2 */
 111
 112         return parent_rate / (div + 1);
 113 }
 114
 115 static struct clk clk_mdivclk = {
 116         .name           = "mdivclk",
 117         .parent         = &clk_mpllref,
 118         .id             = -1,
 119         .ops            = &(struct clk_ops) {
 120                 .get_rate       = s3c2443_getrate_mdivclk,
 121         },
 122 };
 123
 124 static struct clk *clk_msysclk_sources[] = {
 125         [0] = &clk_mpllref,
 126         [1] = &clk_mpll,
 127         [2] = &clk_mdivclk,
 128         [3] = &clk_mpllref,
 129 };
 130
 131 struct clksrc_clk clk_msysclk = {
 132         .clk    = {
 133                 .name           = "msysclk",
 134                 .parent         = &clk_xtal,
 135                 .id             = -1,
 136         },
 137         .sources = &(struct clksrc_sources) {
 138                 .sources = clk_msysclk_sources,
 139                 .nr_sources = ARRAY_SIZE(clk_msysclk_sources),
 140         },
 141         .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 3 },
 142 };
 143
 144 /* prediv
 145  *
 146  * this divides the msysclk down to pass to h/p/etc.
 147  */
 148
 149 static unsigned long s3c2443_prediv_getrate(struct clk *clk)
 150 {
 151         unsigned long rate = clk_get_rate(clk->parent);
 152         unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0);
 153
 154         clkdiv0 &= S3C2443_CLKDIV0_PREDIV_MASK;
 155         clkdiv0 >>= S3C2443_CLKDIV0_PREDIV_SHIFT;
 156
 157         return rate / (clkdiv0 + 1);
 158 }
 159
 160 static struct clk clk_prediv = {
 161         .name           = "prediv",
 162         .id             = -1,
 163         .parent         = &clk_msysclk.clk,
 164         .ops            = &(struct clk_ops) {
 165                 .get_rate       = s3c2443_prediv_getrate,
 166         },
 167 };
 168
 169 /* usbhost
 170  *
 171  * usb host bus-clock, usually 48MHz to provide USB bus clock timing
 172 */
 173
 174 static struct clksrc_clk clk_usb_bus_host = {
 175         .clk    = {
 176                 .name           = "usb-bus-host-parent",
 177                 .id             = -1,
 178                 .parent         = &clk_esysclk.clk,
 179                 .ctrlbit        = S3C2443_SCLKCON_USBHOST,
 180                 .enable         = s3c2443_clkcon_enable_s,
 181         },
 182         .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 4 },
 183 };
 184
 185 /* common clksrc clocks */
 186
 187 static struct clksrc_clk clksrc_clks[] = {
 188         {
 189                 /* ART baud-rate clock sourced from esysclk via a divisor */
 190                 .clk    = {
 191                         .name           = "uartclk",
 192                         .id             = -1,
 193                         .parent         = &clk_esysclk.clk,
 194                 },
 195                 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 8 },
 196         }, {
 197                 /* camera interface bus-clock, divided down from esysclk */
 198                 .clk    = {
 199                         .name           = "camif-upll", /* same as 2440 name */
 200                         .id             = -1,
 201                         .parent         = &clk_esysclk.clk,
 202                         .ctrlbit        = S3C2443_SCLKCON_CAMCLK,
 203                         .enable         = s3c2443_clkcon_enable_s,
 204                 },
 205                 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 26 },
 206         }, {
 207                 .clk    = {
 208                         .name           = "display-if",
 209                         .id             = -1,
 210                         .parent         = &clk_esysclk.clk,
 211                         .ctrlbit        = S3C2443_SCLKCON_DISPCLK,
 212                         .enable         = s3c2443_clkcon_enable_s,
 213                 },
 214                 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 8, .shift = 16 },
 215         },
 216 };
 217
 218
 219 static struct clk init_clocks_off[] = {
 220         {
 221                 .name           = "adc",
 222                 .id             = -1,
 223                 .parent         = &clk_p,
 224                 .enable         = s3c2443_clkcon_enable_p,
 225                 .ctrlbit        = S3C2443_PCLKCON_ADC,
 226         }, {
 227                 .name           = "i2c",
 228                 .id             = -1,
 229                 .parent         = &clk_p,
 230                 .enable         = s3c2443_clkcon_enable_p,
 231                 .ctrlbit        = S3C2443_PCLKCON_IIC,
 232         }
 233 };
 234
 235 static struct clk init_clocks[] = {
 236         {
 237                 .name           = "dma",
 238                 .id             = 0,
 239                 .parent         = &clk_h,
 240                 .enable         = s3c2443_clkcon_enable_h,
 241                 .ctrlbit        = S3C2443_HCLKCON_DMA0,
 242         }, {
 243                 .name           = "dma",
 244                 .id             = 1,
 245                 .parent         = &clk_h,
 246                 .enable         = s3c2443_clkcon_enable_h,
 247                 .ctrlbit        = S3C2443_HCLKCON_DMA1,
 248         }, {
 249                 .name           = "dma",
 250                 .id             = 2,
 251                 .parent         = &clk_h,
 252                 .enable         = s3c2443_clkcon_enable_h,
 253                 .ctrlbit        = S3C2443_HCLKCON_DMA2,
 254         }, {
 255                 .name           = "dma",
 256                 .id             = 3,
 257                 .parent         = &clk_h,
 258                 .enable         = s3c2443_clkcon_enable_h,
 259                 .ctrlbit        = S3C2443_HCLKCON_DMA3,
 260         }, {
 261                 .name           = "dma",
 262                 .id             = 4,
 263                 .parent         = &clk_h,
 264                 .enable         = s3c2443_clkcon_enable_h,
 265                 .ctrlbit        = S3C2443_HCLKCON_DMA4,
 266         }, {
 267                 .name           = "dma",
 268                 .id             = 5,
 269                 .parent         = &clk_h,
 270                 .enable         = s3c2443_clkcon_enable_h,
 271                 .ctrlbit        = S3C2443_HCLKCON_DMA5,
 272         }, {
 273                 .name           = "hsmmc",
 274                 .id             = 1,
 275                 .parent         = &clk_h,
 276                 .enable         = s3c2443_clkcon_enable_h,
 277                 .ctrlbit        = S3C2443_HCLKCON_HSMMC,
 278         }, {
 279                 .name           = "gpio",
 280                 .id             = -1,
 281                 .parent         = &clk_p,
 282                 .enable         = s3c2443_clkcon_enable_p,
 283                 .ctrlbit        = S3C2443_PCLKCON_GPIO,
 284         }, {
 285                 .name           = "usb-host",
 286                 .id             = -1,
 287                 .parent         = &clk_h,
 288                 .enable         = s3c2443_clkcon_enable_h,
 289                 .ctrlbit        = S3C2443_HCLKCON_USBH,
 290         }, {
 291                 .name           = "usb-device",
 292                 .id             = -1,
 293                 .parent         = &clk_h,
 294                 .enable         = s3c2443_clkcon_enable_h,
 295                 .ctrlbit        = S3C2443_HCLKCON_USBD,
 296         }, {
 297                 .name           = "lcd",
 298                 .id             = -1,
 299                 .parent         = &clk_h,
 300                 .enable         = s3c2443_clkcon_enable_h,
 301                 .ctrlbit        = S3C2443_HCLKCON_LCDC,
 302
 303         }, {
 304                 .name           = "timers",
 305                 .id             = -1,
 306                 .parent         = &clk_p,
 307                 .enable         = s3c2443_clkcon_enable_p,
 308                 .ctrlbit        = S3C2443_PCLKCON_PWMT,
 309         }, {
 310                 .name           = "cfc",
 311                 .id             = -1,
 312                 .parent         = &clk_h,
 313                 .enable         = s3c2443_clkcon_enable_h,
 314                 .ctrlbit        = S3C2443_HCLKCON_CFC,
 315         }, {
 316                 .name           = "ssmc",
 317                 .id             = -1,
 318                 .parent         = &clk_h,
 319                 .enable         = s3c2443_clkcon_enable_h,
 320                 .ctrlbit        = S3C2443_HCLKCON_SSMC,
 321         }, {
 322                 .name           = "uart",
 323                 .id             = 0,
 324                 .parent         = &clk_p,
 325                 .enable         = s3c2443_clkcon_enable_p,
 326                 .ctrlbit        = S3C2443_PCLKCON_UART0,
 327         }, {
 328                 .name           = "uart",
 329                 .id             = 1,
 330                 .parent         = &clk_p,
 331                 .enable         = s3c2443_clkcon_enable_p,
 332                 .ctrlbit        = S3C2443_PCLKCON_UART1,
 333         }, {
 334                 .name           = "uart",
 335                 .id             = 2,
 336                 .parent         = &clk_p,
 337                 .enable         = s3c2443_clkcon_enable_p,
 338                 .ctrlbit        = S3C2443_PCLKCON_UART2,
 339         }, {
 340                 .name           = "uart",
 341                 .id             = 3,
 342                 .parent         = &clk_p,
 343                 .enable         = s3c2443_clkcon_enable_p,
 344                 .ctrlbit        = S3C2443_PCLKCON_UART3,
 345         }, {
 346                 .name           = "rtc",
 347                 .id             = -1,
 348                 .parent         = &clk_p,
 349                 .enable         = s3c2443_clkcon_enable_p,
 350                 .ctrlbit        = S3C2443_PCLKCON_RTC,
 351         }, {
 352                 .name           = "watchdog",
 353                 .id             = -1,
 354                 .parent         = &clk_p,
 355                 .ctrlbit        = S3C2443_PCLKCON_WDT,
 356         }, {
 357                 .name           = "ac97",
 358                 .id             = -1,
 359                 .parent         = &clk_p,
 360                 .ctrlbit        = S3C2443_PCLKCON_AC97,
 361         }, {
 362                 .name           = "nand",
 363                 .id             = -1,
 364                 .parent         = &clk_h,
 365         }, {
 366                 .name           = "usb-bus-host",
 367                 .id             = -1,
 368                 .parent         = &clk_usb_bus_host.clk,
 369         }
 370 };
 371
 372 static inline unsigned long s3c2443_get_hdiv(unsigned long clkcon0)
 373 {
 374         clkcon0 &= S3C2443_CLKDIV0_HCLKDIV_MASK;
 375
 376         return clkcon0 + 1;
 377 }
 378
 379 /* EPLLCON compatible enough to get on/off information */
 380
 381 void __init_or_cpufreq s3c2443_common_setup_clocks(pll_fn get_mpll,
 382                                                    fdiv_fn get_fdiv)
 383 {
 384         unsigned long epllcon = __raw_readl(S3C2443_EPLLCON);
 385         unsigned long mpllcon = __raw_readl(S3C2443_MPLLCON);
 386         unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0);
 387         struct clk *xtal_clk;
 388         unsigned long xtal;
 389         unsigned long pll;
 390         unsigned long fclk;
 391         unsigned long hclk;
 392         unsigned long pclk;
 393         int ptr;
 394
 395         xtal_clk = clk_get(NULL, "xtal");
 396         xtal = clk_get_rate(xtal_clk);
 397         clk_put(xtal_clk);
 398
 399         pll = get_mpll(mpllcon, xtal);
 400         clk_msysclk.clk.rate = pll;
 401
 402         fclk = pll / get_fdiv(clkdiv0);
 403         hclk = s3c2443_prediv_getrate(&clk_prediv);
 404         hclk /= s3c2443_get_hdiv(clkdiv0);
 405         pclk = hclk / ((clkdiv0 & S3C2443_CLKDIV0_HALF_PCLK) ? 2 : 1);
 406
 407         s3c24xx_setup_clocks(fclk, hclk, pclk);
 408
 409         printk("CPU: MPLL %s %ld.%03ld MHz, cpu %ld.%03ld MHz, mem %ld.%03ld MHz, pclk %ld.%03ld MHz\n",
 410                (mpllcon & S3C2443_PLLCON_OFF) ? "off":"on",
 411                print_mhz(pll), print_mhz(fclk),
 412                print_mhz(hclk), print_mhz(pclk));
 413
 414         for (ptr = 0; ptr < ARRAY_SIZE(clksrc_clks); ptr++)
 415                 s3c_set_clksrc(&clksrc_clks[ptr], true);
 416
 417         /* ensure usb bus clock is within correct rate of 48MHz */
 418
 419         if (clk_get_rate(&clk_usb_bus_host.clk) != (48 * 1000 * 1000)) {
 420                 printk(KERN_INFO "Warning: USB host bus not at 48MHz\n");
 421                 clk_set_rate(&clk_usb_bus_host.clk, 48*1000*1000);
 422         }
 423
 424         printk("CPU: EPLL %s %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
 425                (epllcon & S3C2443_PLLCON_OFF) ? "off":"on",
 426                print_mhz(clk_get_rate(&clk_epll)),
 427                print_mhz(clk_get_rate(&clk_usb_bus)));
 428 }
 429
 430 static struct clk *clks[] __initdata = {
 431         &clk_prediv,
 432         &clk_mpllref,
 433         &clk_mdivclk,
 434         &clk_ext,
 435         &clk_epll,
 436         &clk_usb_bus,
 437 };
 438
 439 static struct clksrc_clk *clksrcs[] __initdata = {
 440         &clk_usb_bus_host,
 441         &clk_epllref,
 442         &clk_esysclk,
 443         &clk_msysclk,
 444 };
 445
 446 void __init s3c2443_common_init_clocks(int xtal, pll_fn get_mpll,
 447                                        fdiv_fn get_fdiv)
 448 {
 449         int ptr;
 450
 451         /* s3c2443 parents h and p clocks from prediv */
 452         clk_h.parent = &clk_prediv;
 453         clk_p.parent = &clk_prediv;
 454
 455         clk_usb_bus.parent = &clk_usb_bus_host.clk;
 456         clk_epll.parent = &clk_epllref.clk;
 457
 458         s3c24xx_register_baseclocks(xtal);
 459         s3c24xx_register_clocks(clks, ARRAY_SIZE(clks));
 460
 461         for (ptr = 0; ptr < ARRAY_SIZE(clksrcs); ptr++)
 462                 s3c_register_clksrc(clksrcs[ptr], 1);
 463
 464         s3c_register_clksrc(clksrc_clks, ARRAY_SIZE(clksrc_clks));
 465         s3c_register_clocks(init_clocks, ARRAY_SIZE(init_clocks));
 466
 467         /* See s3c2443/etc notes on disabling clocks at init time */
 468         s3c_register_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
 469         s3c_disable_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
 470
 471         s3c2443_common_setup_clocks(get_mpll, get_fdiv);
 472 }