drivers/clk/pxa/clk-pxa27x.c

   1 /*
   2  * Marvell PXA27x family clocks
   3  *
   4  * Copyright (C) 2014 Robert Jarzmik
   5  *
   6  * Heavily inspired from former arch/arm/mach-pxa/clock.c.
   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; version 2 of the License.
  11  *
  12  */
  13 #include <linux/clk-provider.h>
  14 #include <mach/pxa2xx-regs.h>
  15 #include <linux/io.h>
  16 #include <linux/clk.h>
  17 #include <linux/clkdev.h>
  18 #include <linux/of.h>
  19
  20 #include <mach/smemc.h>
  21
  22 #include <dt-bindings/clock/pxa-clock.h>
  23 #include "clk-pxa.h"
  24
  25 #define KHz 1000
  26 #define MHz (1000 * 1000)
  27
  28 enum {
  29         PXA_CORE_13Mhz = 0,
  30         PXA_CORE_RUN,
  31         PXA_CORE_TURBO,
  32 };
  33
  34 enum {
  35         PXA_BUS_13Mhz = 0,
  36         PXA_BUS_RUN,
  37 };
  38
  39 enum {
  40         PXA_LCD_13Mhz = 0,
  41         PXA_LCD_RUN,
  42 };
  43
  44 enum {
  45         PXA_MEM_13Mhz = 0,
  46         PXA_MEM_SYSTEM_BUS,
  47         PXA_MEM_RUN,
  48 };
  49
  50 #define PXA27x_CLKCFG(B, HT, T)                 \
  51         (CLKCFG_FCS |                           \
  52          ((B)  ? CLKCFG_FASTBUS : 0) |          \
  53          ((HT) ? CLKCFG_HALFTURBO : 0) |        \
  54          ((T)  ? CLKCFG_TURBO : 0))
  55 #define PXA27x_CCCR(A, L, N2) (A << 25 | N2 << 7 | L)
  56
  57 #define MDCNFG_DRAC2(mdcnfg)    (((mdcnfg) >> 21) & 0x3)
  58 #define MDCNFG_DRAC0(mdcnfg)    (((mdcnfg) >> 5) & 0x3)
  59
  60 /* Define the refresh period in mSec for the SDRAM and the number of rows */
  61 #define SDRAM_TREF      64      /* standard 64ms SDRAM */
  62
  63 static const char * const get_freq_khz[] = {
  64         "core", "run", "cpll", "memory",
  65         "system_bus"
  66 };
  67
  68 static int get_sdram_rows(void)
  69 {
  70         static int sdram_rows;
  71         unsigned int drac2 = 0, drac0 = 0;
  72         u32 mdcnfg;
  73
  74         if (sdram_rows)
  75                 return sdram_rows;
  76
  77         mdcnfg = readl_relaxed(MDCNFG);
  78
  79         if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3))
  80                 drac2 = MDCNFG_DRAC2(mdcnfg);
  81
  82         if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1))
  83                 drac0 = MDCNFG_DRAC0(mdcnfg);
  84
  85         sdram_rows = 1 << (11 + max(drac0, drac2));
  86         return sdram_rows;
  87 }
  88
  89 static u32 mdrefr_dri(unsigned int freq_khz)
  90 {
  91         u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows();
  92
  93         return (interval - 31) / 32;
  94 }
  95
  96 /*
  97  * Get the clock frequency as reflected by CCSR and the turbo flag.
  98  * We assume these values have been applied via a fcs.
  99  * If info is not 0 we also display the current settings.
 100  */
 101 unsigned int pxa27x_get_clk_frequency_khz(int info)
 102 {
 103         struct clk *clk;
 104         unsigned long clks[5];
 105         int i;
 106
 107         for (i = 0; i < 5; i++) {
 108                 clk = clk_get(NULL, get_freq_khz[i]);
 109                 if (IS_ERR(clk)) {
 110                         clks[i] = 0;
 111                 } else {
 112                         clks[i] = clk_get_rate(clk);
 113                         clk_put(clk);
 114                 }
 115         }
 116         if (info) {
 117                 pr_info("Run Mode clock: %ld.%02ldMHz\n",
 118                         clks[1] / 1000000, (clks[1] % 1000000) / 10000);
 119                 pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
 120                         clks[2] / 1000000, (clks[2] % 1000000) / 10000);
 121                 pr_info("Memory clock: %ld.%02ldMHz\n",
 122                         clks[3] / 1000000, (clks[3] % 1000000) / 10000);
 123                 pr_info("System bus clock: %ld.%02ldMHz\n",
 124                         clks[4] / 1000000, (clks[4] % 1000000) / 10000);
 125         }
 126         return (unsigned int)clks[0] / KHz;
 127 }
 128
 129 bool pxa27x_is_ppll_disabled(void)
 130 {
 131         unsigned long ccsr = readl(CCSR);
 132
 133         return ccsr & (1 << CCCR_PPDIS_BIT);
 134 }
 135
 136 #define PXA27X_CKEN(dev_id, con_id, parents, mult_hp, div_hp,           \
 137                     bit, is_lp, flags)                                  \
 138         PXA_CKEN(dev_id, con_id, bit, parents, 1, 1, mult_hp, div_hp,   \
 139                  is_lp,  CKEN, CKEN_ ## bit, flags)
 140 #define PXA27X_PBUS_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)   \
 141         PXA27X_CKEN(dev_id, con_id, pxa27x_pbus_parents, mult_hp,       \
 142                     div_hp, bit, pxa27x_is_ppll_disabled, 0)
 143
 144 PARENTS(pxa27x_pbus) = { "osc_13mhz", "ppll_312mhz" };
 145 PARENTS(pxa27x_sbus) = { "system_bus", "system_bus" };
 146 PARENTS(pxa27x_32Mhz_bus) = { "osc_32_768khz", "osc_32_768khz" };
 147 PARENTS(pxa27x_lcd_bus) = { "lcd_base", "lcd_base" };
 148 PARENTS(pxa27x_membus) = { "lcd_base", "lcd_base" };
 149
 150 #define PXA27X_CKEN_1RATE(dev_id, con_id, bit, parents, delay)          \
 151         PXA_CKEN_1RATE(dev_id, con_id, bit, parents,                    \
 152                        CKEN, CKEN_ ## bit, 0)
 153 #define PXA27X_CKEN_1RATE_AO(dev_id, con_id, bit, parents, delay)       \
 154         PXA_CKEN_1RATE(dev_id, con_id, bit, parents,                    \
 155                        CKEN, CKEN_ ## bit, CLK_IGNORE_UNUSED)
 156
 157 static struct desc_clk_cken pxa27x_clocks[] __initdata = {
 158         PXA27X_PBUS_CKEN("pxa2xx-uart.0", NULL, FFUART, 2, 42, 1),
 159         PXA27X_PBUS_CKEN("pxa2xx-uart.1", NULL, BTUART, 2, 42, 1),
 160         PXA27X_PBUS_CKEN("pxa2xx-uart.2", NULL, STUART, 2, 42, 1),
 161         PXA27X_PBUS_CKEN("pxa2xx-i2s", NULL, I2S, 2, 51, 0),
 162         PXA27X_PBUS_CKEN("pxa2xx-i2c.0", NULL, I2C, 2, 19, 0),
 163         PXA27X_PBUS_CKEN("pxa27x-udc", NULL, USB, 2, 13, 5),
 164         PXA27X_PBUS_CKEN("pxa2xx-mci.0", NULL, MMC, 2, 32, 0),
 165         PXA27X_PBUS_CKEN("pxa2xx-ir", "FICPCLK", FICP, 2, 13, 0),
 166         PXA27X_PBUS_CKEN("pxa27x-ohci", NULL, USBHOST, 2, 13, 0),
 167         PXA27X_PBUS_CKEN("pxa2xx-i2c.1", NULL, PWRI2C, 1, 24, 0),
 168         PXA27X_PBUS_CKEN("pxa27x-ssp.0", NULL, SSP1, 1, 24, 0),
 169         PXA27X_PBUS_CKEN("pxa27x-ssp.1", NULL, SSP2, 1, 24, 0),
 170         PXA27X_PBUS_CKEN("pxa27x-ssp.2", NULL, SSP3, 1, 24, 0),
 171         PXA27X_PBUS_CKEN("pxa27x-pwm.0", NULL, PWM0, 1, 24, 0),
 172         PXA27X_PBUS_CKEN("pxa27x-pwm.1", NULL, PWM1, 1, 24, 0),
 173         PXA27X_PBUS_CKEN(NULL, "MSLCLK", MSL, 2, 13, 0),
 174         PXA27X_PBUS_CKEN(NULL, "USIMCLK", USIM, 2, 13, 0),
 175         PXA27X_PBUS_CKEN(NULL, "MSTKCLK", MEMSTK, 2, 32, 0),
 176         PXA27X_PBUS_CKEN(NULL, "AC97CLK", AC97, 1, 1, 0),
 177         PXA27X_PBUS_CKEN(NULL, "AC97CONFCLK", AC97CONF, 1, 1, 0),
 178         PXA27X_PBUS_CKEN(NULL, "OSTIMER0", OSTIMER, 1, 96, 0),
 179
 180         PXA27X_CKEN_1RATE("pxa27x-keypad", NULL, KEYPAD,
 181                           pxa27x_32Mhz_bus_parents, 0),
 182         PXA27X_CKEN_1RATE(NULL, "IMCLK", IM, pxa27x_sbus_parents, 0),
 183         PXA27X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, pxa27x_lcd_bus_parents, 0),
 184         PXA27X_CKEN_1RATE("pxa27x-camera.0", NULL, CAMERA,
 185                           pxa27x_lcd_bus_parents, 0),
 186         PXA27X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
 187                              pxa27x_membus_parents, 0),
 188
 189 };
 190
 191 /*
 192  * PXA270 definitions
 193  *
 194  * For the PXA27x:
 195  * Control variables are A, L, 2N for CCCR; B, HT, T for CLKCFG.
 196  *
 197  * A = 0 => memory controller clock from table 3-7,
 198  * A = 1 => memory controller clock = system bus clock
 199  * Run mode frequency   = 13 MHz * L
 200  * Turbo mode frequency = 13 MHz * L * N
 201  * System bus frequency = 13 MHz * L / (B + 1)
 202  *
 203  * In CCCR:
 204  * A = 1
 205  * L = 16         oscillator to run mode ratio
 206  * 2N = 6         2 * (turbo mode to run mode ratio)
 207  *
 208  * In CCLKCFG:
 209  * B = 1          Fast bus mode
 210  * HT = 0         Half-Turbo mode
 211  * T = 1          Turbo mode
 212  *
 213  * For now, just support some of the combinations in table 3-7 of
 214  * PXA27x Processor Family Developer's Manual to simplify frequency
 215  * change sequences.
 216  */
 217 static struct pxa2xx_freq pxa27x_freqs[] = {
 218         {104000000, 104000, PXA27x_CCCR(1,  8, 2), 0, PXA27x_CLKCFG(1, 0, 1) },
 219         {156000000, 104000, PXA27x_CCCR(1,  8, 3), 0, PXA27x_CLKCFG(1, 0, 1) },
 220         {208000000, 208000, PXA27x_CCCR(0, 16, 2), 1, PXA27x_CLKCFG(0, 0, 1) },
 221         {312000000, 208000, PXA27x_CCCR(1, 16, 3), 1, PXA27x_CLKCFG(1, 0, 1) },
 222         {416000000, 208000, PXA27x_CCCR(1, 16, 4), 1, PXA27x_CLKCFG(1, 0, 1) },
 223         {520000000, 208000, PXA27x_CCCR(1, 16, 5), 1, PXA27x_CLKCFG(1, 0, 1) },
 224         {624000000, 208000, PXA27x_CCCR(1, 16, 6), 1, PXA27x_CLKCFG(1, 0, 1) },
 225 };
 226
 227 static unsigned long clk_pxa27x_cpll_get_rate(struct clk_hw *hw,
 228         unsigned long parent_rate)
 229 {
 230         unsigned long clkcfg;
 231         unsigned int t, ht;
 232         unsigned int l, L, n2, N;
 233         unsigned long ccsr = readl(CCSR);
 234
 235         asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
 236         t  = clkcfg & (1 << 0);
 237         ht = clkcfg & (1 << 2);
 238
 239         l  = ccsr & CCSR_L_MASK;
 240         n2 = (ccsr & CCSR_N2_MASK) >> CCSR_N2_SHIFT;
 241         L  = l * parent_rate;
 242         N  = (L * n2) / 2;
 243
 244         return N;
 245 }
 246
 247 static int clk_pxa27x_cpll_determine_rate(struct clk_hw *hw,
 248                                           struct clk_rate_request *req)
 249 {
 250         return pxa2xx_determine_rate(req, pxa27x_freqs,
 251                                      ARRAY_SIZE(pxa27x_freqs));
 252 }
 253
 254 static int clk_pxa27x_cpll_set_rate(struct clk_hw *hw, unsigned long rate,
 255                                     unsigned long parent_rate)
 256 {
 257         int i;
 258
 259         pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate);
 260         for (i = 0; i < ARRAY_SIZE(pxa27x_freqs); i++)
 261                 if (pxa27x_freqs[i].cpll == rate)
 262                         break;
 263
 264         if (i >= ARRAY_SIZE(pxa27x_freqs))
 265                 return -EINVAL;
 266
 267         pxa2xx_cpll_change(&pxa27x_freqs[i], mdrefr_dri, MDREFR, CCCR);
 268         return 0;
 269 }
 270
 271 PARENTS(clk_pxa27x_cpll) = { "osc_13mhz" };
 272 RATE_OPS(clk_pxa27x_cpll, "cpll");
 273
 274 static unsigned long clk_pxa27x_lcd_base_get_rate(struct clk_hw *hw,
 275                                                   unsigned long parent_rate)
 276 {
 277         unsigned int l, osc_forced;
 278         unsigned long ccsr = readl(CCSR);
 279         unsigned long cccr = readl(CCCR);
 280
 281         l  = ccsr & CCSR_L_MASK;
 282         osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
 283         if (osc_forced) {
 284                 if (cccr & (1 << CCCR_LCD_26_BIT))
 285                         return parent_rate * 2;
 286                 else
 287                         return parent_rate;
 288         }
 289
 290         if (l <= 7)
 291                 return parent_rate;
 292         if (l <= 16)
 293                 return parent_rate / 2;
 294         return parent_rate / 4;
 295 }
 296
 297 static u8 clk_pxa27x_lcd_base_get_parent(struct clk_hw *hw)
 298 {
 299         unsigned int osc_forced;
 300         unsigned long ccsr = readl(CCSR);
 301
 302         osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
 303         if (osc_forced)
 304                 return PXA_LCD_13Mhz;
 305         else
 306                 return PXA_LCD_RUN;
 307 }
 308
 309 PARENTS(clk_pxa27x_lcd_base) = { "osc_13mhz", "run" };
 310 MUX_RO_RATE_RO_OPS(clk_pxa27x_lcd_base, "lcd_base");
 311
 312 static void __init pxa27x_register_plls(void)
 313 {
 314         clk_register_fixed_rate(NULL, "osc_13mhz", NULL,
 315                                 CLK_GET_RATE_NOCACHE,
 316                                 13 * MHz);
 317         clkdev_pxa_register(CLK_OSC32k768, "osc_32_768khz", NULL,
 318                             clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
 319                                                     CLK_GET_RATE_NOCACHE,
 320                                                     32768 * KHz));
 321         clk_register_fixed_rate(NULL, "clk_dummy", NULL, 0, 0);
 322         clk_register_fixed_factor(NULL, "ppll_312mhz", "osc_13mhz", 0, 24, 1);
 323 }
 324
 325 static u8 clk_pxa27x_core_get_parent(struct clk_hw *hw)
 326 {
 327         unsigned long clkcfg;
 328         unsigned int t, ht, osc_forced;
 329         unsigned long ccsr = readl(CCSR);
 330
 331         osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
 332         if (osc_forced)
 333                 return PXA_CORE_13Mhz;
 334
 335         asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
 336         t  = clkcfg & (1 << 0);
 337         ht = clkcfg & (1 << 2);
 338
 339         if (ht || t)
 340                 return PXA_CORE_TURBO;
 341         return PXA_CORE_RUN;
 342 }
 343
 344 static int clk_pxa27x_core_set_parent(struct clk_hw *hw, u8 index)
 345 {
 346         if (index > PXA_CORE_TURBO)
 347                 return -EINVAL;
 348
 349         pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO);
 350
 351         return 0;
 352 }
 353
 354 static int clk_pxa27x_core_determine_rate(struct clk_hw *hw,
 355                                           struct clk_rate_request *req)
 356 {
 357         return __clk_mux_determine_rate(hw, req);
 358 }
 359
 360 PARENTS(clk_pxa27x_core) = { "osc_13mhz", "run", "cpll" };
 361 MUX_OPS(clk_pxa27x_core, "core", CLK_SET_RATE_PARENT);
 362
 363 static unsigned long clk_pxa27x_run_get_rate(struct clk_hw *hw,
 364                                              unsigned long parent_rate)
 365 {
 366         unsigned long ccsr = readl(CCSR);
 367         unsigned int n2 = (ccsr & CCSR_N2_MASK) >> CCSR_N2_SHIFT;
 368
 369         return (parent_rate / n2) * 2;
 370 }
 371 PARENTS(clk_pxa27x_run) = { "cpll" };
 372 RATE_RO_OPS(clk_pxa27x_run, "run");
 373
 374 static void __init pxa27x_register_core(void)
 375 {
 376         clkdev_pxa_register(CLK_NONE, "cpll", NULL,
 377                             clk_register_clk_pxa27x_cpll());
 378         clkdev_pxa_register(CLK_NONE, "run", NULL,
 379                             clk_register_clk_pxa27x_run());
 380         clkdev_pxa_register(CLK_CORE, "core", NULL,
 381                             clk_register_clk_pxa27x_core());
 382 }
 383
 384 static unsigned long clk_pxa27x_system_bus_get_rate(struct clk_hw *hw,
 385                                                     unsigned long parent_rate)
 386 {
 387         unsigned long clkcfg;
 388         unsigned int b, osc_forced;
 389         unsigned long ccsr = readl(CCSR);
 390
 391         osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
 392         asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
 393         b  = clkcfg & (1 << 3);
 394
 395         if (osc_forced)
 396                 return parent_rate;
 397         if (b)
 398                 return parent_rate;
 399         else
 400                 return parent_rate / 2;
 401 }
 402
 403 static u8 clk_pxa27x_system_bus_get_parent(struct clk_hw *hw)
 404 {
 405         unsigned int osc_forced;
 406         unsigned long ccsr = readl(CCSR);
 407
 408         osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
 409         if (osc_forced)
 410                 return PXA_BUS_13Mhz;
 411         else
 412                 return PXA_BUS_RUN;
 413 }
 414
 415 PARENTS(clk_pxa27x_system_bus) = { "osc_13mhz", "run" };
 416 MUX_RO_RATE_RO_OPS(clk_pxa27x_system_bus, "system_bus");
 417
 418 static unsigned long clk_pxa27x_memory_get_rate(struct clk_hw *hw,
 419                                                 unsigned long parent_rate)
 420 {
 421         unsigned int a, l, osc_forced;
 422         unsigned long cccr = readl(CCCR);
 423         unsigned long ccsr = readl(CCSR);
 424
 425         osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
 426         a = cccr & (1 << CCCR_A_BIT);
 427         l  = ccsr & CCSR_L_MASK;
 428
 429         if (osc_forced || a)
 430                 return parent_rate;
 431         if (l <= 10)
 432                 return parent_rate;
 433         if (l <= 20)
 434                 return parent_rate / 2;
 435         return parent_rate / 4;
 436 }
 437
 438 static u8 clk_pxa27x_memory_get_parent(struct clk_hw *hw)
 439 {
 440         unsigned int osc_forced, a;
 441         unsigned long cccr = readl(CCCR);
 442         unsigned long ccsr = readl(CCSR);
 443
 444         osc_forced = ccsr & (1 << CCCR_CPDIS_BIT);
 445         a = cccr & (1 << CCCR_A_BIT);
 446         if (osc_forced)
 447                 return PXA_MEM_13Mhz;
 448         if (a)
 449                 return PXA_MEM_SYSTEM_BUS;
 450         else
 451                 return PXA_MEM_RUN;
 452 }
 453
 454 PARENTS(clk_pxa27x_memory) = { "osc_13mhz", "system_bus", "run" };
 455 MUX_RO_RATE_RO_OPS(clk_pxa27x_memory, "memory");
 456
 457 #define DUMMY_CLK(_con_id, _dev_id, _parent) \
 458         { .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
 459 struct dummy_clk {
 460         const char *con_id;
 461         const char *dev_id;
 462         const char *parent;
 463 };
 464 static struct dummy_clk dummy_clks[] __initdata = {
 465         DUMMY_CLK(NULL, "pxa27x-gpio", "osc_32_768khz"),
 466         DUMMY_CLK(NULL, "pxa-rtc", "osc_32_768khz"),
 467         DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
 468         DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
 469 };
 470
 471 static void __init pxa27x_dummy_clocks_init(void)
 472 {
 473         struct clk *clk;
 474         struct dummy_clk *d;
 475         const char *name;
 476         int i;
 477
 478         for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
 479                 d = &dummy_clks[i];
 480                 name = d->dev_id ? d->dev_id : d->con_id;
 481                 clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
 482                 clk_register_clkdev(clk, d->con_id, d->dev_id);
 483         }
 484 }
 485
 486 static void __init pxa27x_base_clocks_init(void)
 487 {
 488         pxa27x_register_plls();
 489         pxa27x_register_core();
 490         clkdev_pxa_register(CLK_NONE, "system_bus", NULL,
 491                             clk_register_clk_pxa27x_system_bus());
 492         clkdev_pxa_register(CLK_NONE, "memory", NULL,
 493                             clk_register_clk_pxa27x_memory());
 494         clk_register_clk_pxa27x_lcd_base();
 495 }
 496
 497 int __init pxa27x_clocks_init(void)
 498 {
 499         pxa27x_base_clocks_init();
 500         pxa27x_dummy_clocks_init();
 501         return clk_pxa_cken_init(pxa27x_clocks, ARRAY_SIZE(pxa27x_clocks));
 502 }
 503
 504 static void __init pxa27x_dt_clocks_init(struct device_node *np)
 505 {
 506         pxa27x_clocks_init();
 507         clk_pxa_dt_common_init(np);
 508 }
 509 CLK_OF_DECLARE(pxa_clks, "marvell,pxa270-clocks", pxa27x_dt_clocks_init);