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 };
  60
  61 static struct clk *clk_epllref_sources[] = {
  62         [0] = &clk_mpllref,
  63         [1] = &clk_mpllref,
  64         [2] = &clk_xtal,
  65         [3] = &clk_ext,
  66 };
  67
  68 struct clksrc_clk clk_epllref = {
  69         .clk    = {
  70                 .name           = "epllref",
  71         },
  72         .sources = &(struct clksrc_sources) {
  73                 .sources = clk_epllref_sources,
  74                 .nr_sources = ARRAY_SIZE(clk_epllref_sources),
  75         },
  76         .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 7 },
  77 };
  78
  79 /* esysclk
  80  *
  81  * this is sourced from either the EPLL or the EPLLref clock
  82 */
  83
  84 static struct clk *clk_sysclk_sources[] = {
  85         [0] = &clk_epllref.clk,
  86         [1] = &clk_epll,
  87 };
  88
  89 struct clksrc_clk clk_esysclk = {
  90         .clk    = {
  91                 .name           = "esysclk",
  92                 .parent         = &clk_epll,
  93         },
  94         .sources = &(struct clksrc_sources) {
  95                 .sources = clk_sysclk_sources,
  96                 .nr_sources = ARRAY_SIZE(clk_sysclk_sources),
  97         },
  98         .reg_src = { .reg = S3C2443_CLKSRC, .size = 1, .shift = 6 },
  99 };
 100
 101 static unsigned long s3c2443_getrate_mdivclk(struct clk *clk)
 102 {
 103         unsigned long parent_rate = clk_get_rate(clk->parent);
 104         unsigned long div = __raw_readl(S3C2443_CLKDIV0);
 105
 106         div  &= S3C2443_CLKDIV0_EXTDIV_MASK;
 107         div >>= (S3C2443_CLKDIV0_EXTDIV_SHIFT-1);       /* x2 */
 108
 109         return parent_rate / (div + 1);
 110 }
 111
 112 static struct clk clk_mdivclk = {
 113         .name           = "mdivclk",
 114         .parent         = &clk_mpllref,
 115         .ops            = &(struct clk_ops) {
 116                 .get_rate       = s3c2443_getrate_mdivclk,
 117         },
 118 };
 119
 120 static struct clk *clk_msysclk_sources[] = {
 121         [0] = &clk_mpllref,
 122         [1] = &clk_mpll,
 123         [2] = &clk_mdivclk,
 124         [3] = &clk_mpllref,
 125 };
 126
 127 struct clksrc_clk clk_msysclk = {
 128         .clk    = {
 129                 .name           = "msysclk",
 130                 .parent         = &clk_xtal,
 131         },
 132         .sources = &(struct clksrc_sources) {
 133                 .sources = clk_msysclk_sources,
 134                 .nr_sources = ARRAY_SIZE(clk_msysclk_sources),
 135         },
 136         .reg_src = { .reg = S3C2443_CLKSRC, .size = 2, .shift = 3 },
 137 };
 138
 139 /* prediv
 140  *
 141  * this divides the msysclk down to pass to h/p/etc.
 142  */
 143
 144 static unsigned long s3c2443_prediv_getrate(struct clk *clk)
 145 {
 146         unsigned long rate = clk_get_rate(clk->parent);
 147         unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0);
 148
 149         clkdiv0 &= S3C2443_CLKDIV0_PREDIV_MASK;
 150         clkdiv0 >>= S3C2443_CLKDIV0_PREDIV_SHIFT;
 151
 152         return rate / (clkdiv0 + 1);
 153 }
 154
 155 static struct clk clk_prediv = {
 156         .name           = "prediv",
 157         .parent         = &clk_msysclk.clk,
 158         .ops            = &(struct clk_ops) {
 159                 .get_rate       = s3c2443_prediv_getrate,
 160         },
 161 };
 162
 163 /* usbhost
 164  *
 165  * usb host bus-clock, usually 48MHz to provide USB bus clock timing
 166 */
 167
 168 static struct clksrc_clk clk_usb_bus_host = {
 169         .clk    = {
 170                 .name           = "usb-bus-host-parent",
 171                 .parent         = &clk_esysclk.clk,
 172                 .ctrlbit        = S3C2443_SCLKCON_USBHOST,
 173                 .enable         = s3c2443_clkcon_enable_s,
 174         },
 175         .reg_div = { .reg = S3C2443_CLKDIV1, .size = 2, .shift = 4 },
 176 };
 177
 178 /* common clksrc clocks */
 179
 180 static struct clksrc_clk clksrc_clks[] = {
 181         {
 182                 /* ART baud-rate clock sourced from esysclk via a divisor */
 183                 .clk    = {
 184                         .name           = "uartclk",
 185                         .parent         = &clk_esysclk.clk,
 186                 },
 187                 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 8 },
 188         }, {
 189                 /* camera interface bus-clock, divided down from esysclk */
 190                 .clk    = {
 191                         .name           = "camif-upll", /* same as 2440 name */
 192                         .parent         = &clk_esysclk.clk,
 193                         .ctrlbit        = S3C2443_SCLKCON_CAMCLK,
 194                         .enable         = s3c2443_clkcon_enable_s,
 195                 },
 196                 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 4, .shift = 26 },
 197         }, {
 198                 .clk    = {
 199                         .name           = "display-if",
 200                         .parent         = &clk_esysclk.clk,
 201                         .ctrlbit        = S3C2443_SCLKCON_DISPCLK,
 202                         .enable         = s3c2443_clkcon_enable_s,
 203                 },
 204                 .reg_div = { .reg = S3C2443_CLKDIV1, .size = 8, .shift = 16 },
 205         },
 206 };
 207
 208
 209 static struct clk init_clocks_off[] = {
 210         {
 211                 .name           = "adc",
 212                 .parent         = &clk_p,
 213                 .enable         = s3c2443_clkcon_enable_p,
 214                 .ctrlbit        = S3C2443_PCLKCON_ADC,
 215         }, {
 216                 .name           = "i2c",
 217                 .parent         = &clk_p,
 218                 .enable         = s3c2443_clkcon_enable_p,
 219                 .ctrlbit        = S3C2443_PCLKCON_IIC,
 220         }
 221 };
 222
 223 static struct clk init_clocks[] = {
 224         {
 225                 .name           = "dma",
 226                 .parent         = &clk_h,
 227                 .enable         = s3c2443_clkcon_enable_h,
 228                 .ctrlbit        = S3C2443_HCLKCON_DMA0,
 229         }, {
 230                 .name           = "dma",
 231                 .parent         = &clk_h,
 232                 .enable         = s3c2443_clkcon_enable_h,
 233                 .ctrlbit        = S3C2443_HCLKCON_DMA1,
 234         }, {
 235                 .name           = "dma",
 236                 .parent         = &clk_h,
 237                 .enable         = s3c2443_clkcon_enable_h,
 238                 .ctrlbit        = S3C2443_HCLKCON_DMA2,
 239         }, {
 240                 .name           = "dma",
 241                 .parent         = &clk_h,
 242                 .enable         = s3c2443_clkcon_enable_h,
 243                 .ctrlbit        = S3C2443_HCLKCON_DMA3,
 244         }, {
 245                 .name           = "dma",
 246                 .parent         = &clk_h,
 247                 .enable         = s3c2443_clkcon_enable_h,
 248                 .ctrlbit        = S3C2443_HCLKCON_DMA4,
 249         }, {
 250                 .name           = "dma",
 251                 .parent         = &clk_h,
 252                 .enable         = s3c2443_clkcon_enable_h,
 253                 .ctrlbit        = S3C2443_HCLKCON_DMA5,
 254         }, {
 255                 .name           = "hsmmc",
 256                 .parent         = &clk_h,
 257                 .enable         = s3c2443_clkcon_enable_h,
 258                 .ctrlbit        = S3C2443_HCLKCON_HSMMC,
 259         }, {
 260                 .name           = "gpio",
 261                 .parent         = &clk_p,
 262                 .enable         = s3c2443_clkcon_enable_p,
 263                 .ctrlbit        = S3C2443_PCLKCON_GPIO,
 264         }, {
 265                 .name           = "usb-host",
 266                 .parent         = &clk_h,
 267                 .enable         = s3c2443_clkcon_enable_h,
 268                 .ctrlbit        = S3C2443_HCLKCON_USBH,
 269         }, {
 270                 .name           = "usb-device",
 271                 .parent         = &clk_h,
 272                 .enable         = s3c2443_clkcon_enable_h,
 273                 .ctrlbit        = S3C2443_HCLKCON_USBD,
 274         }, {
 275                 .name           = "lcd",
 276                 .parent         = &clk_h,
 277                 .enable         = s3c2443_clkcon_enable_h,
 278                 .ctrlbit        = S3C2443_HCLKCON_LCDC,
 279
 280         }, {
 281                 .name           = "timers",
 282                 .parent         = &clk_p,
 283                 .enable         = s3c2443_clkcon_enable_p,
 284                 .ctrlbit        = S3C2443_PCLKCON_PWMT,
 285         }, {
 286                 .name           = "cfc",
 287                 .parent         = &clk_h,
 288                 .enable         = s3c2443_clkcon_enable_h,
 289                 .ctrlbit        = S3C2443_HCLKCON_CFC,
 290         }, {
 291                 .name           = "ssmc",
 292                 .parent         = &clk_h,
 293                 .enable         = s3c2443_clkcon_enable_h,
 294                 .ctrlbit        = S3C2443_HCLKCON_SSMC,
 295         }, {
 296                 .name           = "uart",
 297                 .devname        = "s3c2440-uart.0",
 298                 .parent         = &clk_p,
 299                 .enable         = s3c2443_clkcon_enable_p,
 300                 .ctrlbit        = S3C2443_PCLKCON_UART0,
 301         }, {
 302                 .name           = "uart",
 303                 .devname        = "s3c2440-uart.1",
 304                 .parent         = &clk_p,
 305                 .enable         = s3c2443_clkcon_enable_p,
 306                 .ctrlbit        = S3C2443_PCLKCON_UART1,
 307         }, {
 308                 .name           = "uart",
 309                 .devname        = "s3c2440-uart.2",
 310                 .parent         = &clk_p,
 311                 .enable         = s3c2443_clkcon_enable_p,
 312                 .ctrlbit        = S3C2443_PCLKCON_UART2,
 313         }, {
 314                 .name           = "uart",
 315                 .devname        = "s3c2440-uart.3",
 316                 .parent         = &clk_p,
 317                 .enable         = s3c2443_clkcon_enable_p,
 318                 .ctrlbit        = S3C2443_PCLKCON_UART3,
 319         }, {
 320                 .name           = "rtc",
 321                 .parent         = &clk_p,
 322                 .enable         = s3c2443_clkcon_enable_p,
 323                 .ctrlbit        = S3C2443_PCLKCON_RTC,
 324         }, {
 325                 .name           = "watchdog",
 326                 .parent         = &clk_p,
 327                 .ctrlbit        = S3C2443_PCLKCON_WDT,
 328         }, {
 329                 .name           = "ac97",
 330                 .parent         = &clk_p,
 331                 .ctrlbit        = S3C2443_PCLKCON_AC97,
 332         }, {
 333                 .name           = "nand",
 334                 .parent         = &clk_h,
 335         }, {
 336                 .name           = "usb-bus-host",
 337                 .parent         = &clk_usb_bus_host.clk,
 338         }
 339 };
 340
 341 static inline unsigned long s3c2443_get_hdiv(unsigned long clkcon0)
 342 {
 343         clkcon0 &= S3C2443_CLKDIV0_HCLKDIV_MASK;
 344
 345         return clkcon0 + 1;
 346 }
 347
 348 /* EPLLCON compatible enough to get on/off information */
 349
 350 void __init_or_cpufreq s3c2443_common_setup_clocks(pll_fn get_mpll,
 351                                                    fdiv_fn get_fdiv)
 352 {
 353         unsigned long epllcon = __raw_readl(S3C2443_EPLLCON);
 354         unsigned long mpllcon = __raw_readl(S3C2443_MPLLCON);
 355         unsigned long clkdiv0 = __raw_readl(S3C2443_CLKDIV0);
 356         struct clk *xtal_clk;
 357         unsigned long xtal;
 358         unsigned long pll;
 359         unsigned long fclk;
 360         unsigned long hclk;
 361         unsigned long pclk;
 362         int ptr;
 363
 364         xtal_clk = clk_get(NULL, "xtal");
 365         xtal = clk_get_rate(xtal_clk);
 366         clk_put(xtal_clk);
 367
 368         pll = get_mpll(mpllcon, xtal);
 369         clk_msysclk.clk.rate = pll;
 370
 371         fclk = pll / get_fdiv(clkdiv0);
 372         hclk = s3c2443_prediv_getrate(&clk_prediv);
 373         hclk /= s3c2443_get_hdiv(clkdiv0);
 374         pclk = hclk / ((clkdiv0 & S3C2443_CLKDIV0_HALF_PCLK) ? 2 : 1);
 375
 376         s3c24xx_setup_clocks(fclk, hclk, pclk);
 377
 378         printk("CPU: MPLL %s %ld.%03ld MHz, cpu %ld.%03ld MHz, mem %ld.%03ld MHz, pclk %ld.%03ld MHz\n",
 379                (mpllcon & S3C2443_PLLCON_OFF) ? "off":"on",
 380                print_mhz(pll), print_mhz(fclk),
 381                print_mhz(hclk), print_mhz(pclk));
 382
 383         for (ptr = 0; ptr < ARRAY_SIZE(clksrc_clks); ptr++)
 384                 s3c_set_clksrc(&clksrc_clks[ptr], true);
 385
 386         /* ensure usb bus clock is within correct rate of 48MHz */
 387
 388         if (clk_get_rate(&clk_usb_bus_host.clk) != (48 * 1000 * 1000)) {
 389                 printk(KERN_INFO "Warning: USB host bus not at 48MHz\n");
 390                 clk_set_rate(&clk_usb_bus_host.clk, 48*1000*1000);
 391         }
 392
 393         printk("CPU: EPLL %s %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
 394                (epllcon & S3C2443_PLLCON_OFF) ? "off":"on",
 395                print_mhz(clk_get_rate(&clk_epll)),
 396                print_mhz(clk_get_rate(&clk_usb_bus)));
 397 }
 398
 399 static struct clk *clks[] __initdata = {
 400         &clk_prediv,
 401         &clk_mpllref,
 402         &clk_mdivclk,
 403         &clk_ext,
 404         &clk_epll,
 405         &clk_usb_bus,
 406 };
 407
 408 static struct clksrc_clk *clksrcs[] __initdata = {
 409         &clk_usb_bus_host,
 410         &clk_epllref,
 411         &clk_esysclk,
 412         &clk_msysclk,
 413 };
 414
 415 void __init s3c2443_common_init_clocks(int xtal, pll_fn get_mpll,
 416                                        fdiv_fn get_fdiv)
 417 {
 418         int ptr;
 419
 420         /* s3c2443 parents h and p clocks from prediv */
 421         clk_h.parent = &clk_prediv;
 422         clk_p.parent = &clk_prediv;
 423
 424         clk_usb_bus.parent = &clk_usb_bus_host.clk;
 425         clk_epll.parent = &clk_epllref.clk;
 426
 427         s3c24xx_register_baseclocks(xtal);
 428         s3c24xx_register_clocks(clks, ARRAY_SIZE(clks));
 429
 430         for (ptr = 0; ptr < ARRAY_SIZE(clksrcs); ptr++)
 431                 s3c_register_clksrc(clksrcs[ptr], 1);
 432
 433         s3c_register_clksrc(clksrc_clks, ARRAY_SIZE(clksrc_clks));
 434         s3c_register_clocks(init_clocks, ARRAY_SIZE(init_clocks));
 435
 436         /* See s3c2443/etc notes on disabling clocks at init time */
 437         s3c_register_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
 438         s3c_disable_clocks(init_clocks_off, ARRAY_SIZE(init_clocks_off));
 439
 440         s3c2443_common_setup_clocks(get_mpll, get_fdiv);
 441 }