drivers/clk/pxa/clk-pxa25x.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Marvell PXA25x family clocks
   4  *
   5  * Copyright (C) 2014 Robert Jarzmik
   6  *
   7  * Heavily inspired from former arch/arm/mach-pxa/pxa25x.c.
   8  *
   9  * For non-devicetree platforms. Once pxa is fully converted to devicetree, this
  10  * should go away.
  11  */
  12 #include <linux/clk-provider.h>
  13 #include <linux/clk.h>
  14 #include <linux/clkdev.h>
  15 #include <linux/io.h>
  16 #include <linux/of.h>
  17 #include <mach/pxa2xx-regs.h>
  18 #include <mach/smemc.h>
  19
  20 #include <dt-bindings/clock/pxa-clock.h>
  21 #include "clk-pxa.h"
  22
  23 #define KHz 1000
  24 #define MHz (1000 * 1000)
  25
  26 enum {
  27         PXA_CORE_RUN = 0,
  28         PXA_CORE_TURBO,
  29 };
  30
  31 #define PXA25x_CLKCFG(T)                        \
  32         (CLKCFG_FCS |                           \
  33          ((T) ? CLKCFG_TURBO : 0))
  34 #define PXA25x_CCCR(N2, M, L) (N2 << 7 | M << 5 | L)
  35
  36 #define MDCNFG_DRAC2(mdcnfg)    (((mdcnfg) >> 21) & 0x3)
  37 #define MDCNFG_DRAC0(mdcnfg)    (((mdcnfg) >> 5) & 0x3)
  38
  39 /* Define the refresh period in mSec for the SDRAM and the number of rows */
  40 #define SDRAM_TREF      64      /* standard 64ms SDRAM */
  41
  42 /*
  43  * Various clock factors driven by the CCCR register.
  44  */
  45
  46 /* Crystal Frequency to Memory Frequency Multiplier (L) */
  47 static unsigned char L_clk_mult[32] = { 0, 27, 32, 36, 40, 45, 0, };
  48
  49 /* Memory Frequency to Run Mode Frequency Multiplier (M) */
  50 static unsigned char M_clk_mult[4] = { 0, 1, 2, 4 };
  51
  52 /* Run Mode Frequency to Turbo Mode Frequency Multiplier (N) */
  53 /* Note: we store the value N * 2 here. */
  54 static unsigned char N2_clk_mult[8] = { 0, 0, 2, 3, 4, 0, 6, 0 };
  55
  56 static const char * const get_freq_khz[] = {
  57         "core", "run", "cpll", "memory"
  58 };
  59
  60 static int get_sdram_rows(void)
  61 {
  62         static int sdram_rows;
  63         unsigned int drac2 = 0, drac0 = 0;
  64         u32 mdcnfg;
  65
  66         if (sdram_rows)
  67                 return sdram_rows;
  68
  69         mdcnfg = readl_relaxed(MDCNFG);
  70
  71         if (mdcnfg & (MDCNFG_DE2 | MDCNFG_DE3))
  72                 drac2 = MDCNFG_DRAC2(mdcnfg);
  73
  74         if (mdcnfg & (MDCNFG_DE0 | MDCNFG_DE1))
  75                 drac0 = MDCNFG_DRAC0(mdcnfg);
  76
  77         sdram_rows = 1 << (11 + max(drac0, drac2));
  78         return sdram_rows;
  79 }
  80
  81 static u32 mdrefr_dri(unsigned int freq_khz)
  82 {
  83         u32 interval = freq_khz * SDRAM_TREF / get_sdram_rows();
  84
  85         return interval / 32;
  86 }
  87
  88 /*
  89  * Get the clock frequency as reflected by CCCR and the turbo flag.
  90  * We assume these values have been applied via a fcs.
  91  * If info is not 0 we also display the current settings.
  92  */
  93 unsigned int pxa25x_get_clk_frequency_khz(int info)
  94 {
  95         struct clk *clk;
  96         unsigned long clks[5];
  97         int i;
  98
  99         for (i = 0; i < ARRAY_SIZE(get_freq_khz); i++) {
 100                 clk = clk_get(NULL, get_freq_khz[i]);
 101                 if (IS_ERR(clk)) {
 102                         clks[i] = 0;
 103                 } else {
 104                         clks[i] = clk_get_rate(clk);
 105                         clk_put(clk);
 106                 }
 107         }
 108
 109         if (info) {
 110                 pr_info("Run Mode clock: %ld.%02ldMHz\n",
 111                         clks[1] / 1000000, (clks[1] % 1000000) / 10000);
 112                 pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
 113                         clks[2] / 1000000, (clks[2] % 1000000) / 10000);
 114                 pr_info("Memory clock: %ld.%02ldMHz\n",
 115                         clks[3] / 1000000, (clks[3] % 1000000) / 10000);
 116         }
 117
 118         return (unsigned int)clks[0] / KHz;
 119 }
 120
 121 static unsigned long clk_pxa25x_memory_get_rate(struct clk_hw *hw,
 122                                                 unsigned long parent_rate)
 123 {
 124         unsigned long cccr = readl(CCCR);
 125         unsigned int m = M_clk_mult[(cccr >> 5) & 0x03];
 126
 127         return parent_rate / m;
 128 }
 129 PARENTS(clk_pxa25x_memory) = { "run" };
 130 RATE_RO_OPS(clk_pxa25x_memory, "memory");
 131
 132 PARENTS(pxa25x_pbus95) = { "ppll_95_85mhz", "ppll_95_85mhz" };
 133 PARENTS(pxa25x_pbus147) = { "ppll_147_46mhz", "ppll_147_46mhz" };
 134 PARENTS(pxa25x_osc3) = { "osc_3_6864mhz", "osc_3_6864mhz" };
 135
 136 #define PXA25X_CKEN(dev_id, con_id, parents, mult, div,                 \
 137                     bit, is_lp, flags)                                  \
 138         PXA_CKEN(dev_id, con_id, bit, parents, mult, div, mult, div,    \
 139                  is_lp,  CKEN, CKEN_ ## bit, flags)
 140 #define PXA25X_PBUS95_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay) \
 141         PXA25X_CKEN(dev_id, con_id, pxa25x_pbus95_parents, mult_hp,     \
 142                     div_hp, bit, NULL, 0)
 143 #define PXA25X_PBUS147_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)\
 144         PXA25X_CKEN(dev_id, con_id, pxa25x_pbus147_parents, mult_hp,    \
 145                     div_hp, bit, NULL, 0)
 146 #define PXA25X_OSC3_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)   \
 147         PXA25X_CKEN(dev_id, con_id, pxa25x_osc3_parents, mult_hp,       \
 148                     div_hp, bit, NULL, 0)
 149
 150 #define PXA25X_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 PXA25X_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 pxa25x_clocks[] __initdata = {
 158         PXA25X_PBUS95_CKEN("pxa2xx-mci.0", NULL, MMC, 1, 5, 0),
 159         PXA25X_PBUS95_CKEN("pxa2xx-i2c.0", NULL, I2C, 1, 3, 0),
 160         PXA25X_PBUS95_CKEN("pxa2xx-ir", "FICPCLK", FICP, 1, 2, 0),
 161         PXA25X_PBUS95_CKEN("pxa25x-udc", NULL, USB, 1, 2, 5),
 162         PXA25X_PBUS147_CKEN("pxa2xx-uart.0", NULL, FFUART, 1, 10, 1),
 163         PXA25X_PBUS147_CKEN("pxa2xx-uart.1", NULL, BTUART, 1, 10, 1),
 164         PXA25X_PBUS147_CKEN("pxa2xx-uart.2", NULL, STUART, 1, 10, 1),
 165         PXA25X_PBUS147_CKEN("pxa2xx-uart.3", NULL, HWUART, 1, 10, 1),
 166         PXA25X_PBUS147_CKEN("pxa2xx-i2s", NULL, I2S, 1, 10, 0),
 167         PXA25X_PBUS147_CKEN(NULL, "AC97CLK", AC97, 1, 12, 0),
 168         PXA25X_OSC3_CKEN("pxa25x-ssp.0", NULL, SSP, 1, 1, 0),
 169         PXA25X_OSC3_CKEN("pxa25x-nssp.1", NULL, NSSP, 1, 1, 0),
 170         PXA25X_OSC3_CKEN("pxa25x-nssp.2", NULL, ASSP, 1, 1, 0),
 171         PXA25X_OSC3_CKEN("pxa25x-pwm.0", NULL, PWM0, 1, 1, 0),
 172         PXA25X_OSC3_CKEN("pxa25x-pwm.1", NULL, PWM1, 1, 1, 0),
 173
 174         PXA25X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, clk_pxa25x_memory_parents, 0),
 175         PXA25X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
 176                              clk_pxa25x_memory_parents, 0),
 177 };
 178
 179 /*
 180  * In this table, PXA25x_CCCR(N2, M, L) has the following meaning, where :
 181  *   - freq_cpll = n * m * L * 3.6864 MHz
 182  *   - n = N2 / 2
 183  *   - m = 2^(M - 1), where 1 <= M <= 3
 184  *   - l = L_clk_mult[L], ie. { 0, 27, 32, 36, 40, 45, 0, }[L]
 185  */
 186 static struct pxa2xx_freq pxa25x_freqs[] = {
 187         /* CPU  MEMBUS  CCCR                  DIV2 CCLKCFG      */
 188         { 99532800, 99500, PXA25x_CCCR(2,  1, 1),  1, PXA25x_CLKCFG(1)},
 189         {199065600, 99500, PXA25x_CCCR(4,  1, 1),  0, PXA25x_CLKCFG(1)},
 190         {298598400, 99500, PXA25x_CCCR(3,  2, 1),  0, PXA25x_CLKCFG(1)},
 191         {398131200, 99500, PXA25x_CCCR(4,  2, 1),  0, PXA25x_CLKCFG(1)},
 192 };
 193
 194 static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw)
 195 {
 196         unsigned long clkcfg;
 197         unsigned int t;
 198
 199         asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
 200         t  = clkcfg & (1 << 0);
 201         if (t)
 202                 return PXA_CORE_TURBO;
 203         return PXA_CORE_RUN;
 204 }
 205
 206 static int clk_pxa25x_core_set_parent(struct clk_hw *hw, u8 index)
 207 {
 208         if (index > PXA_CORE_TURBO)
 209                 return -EINVAL;
 210
 211         pxa2xx_core_turbo_switch(index == PXA_CORE_TURBO);
 212
 213         return 0;
 214 }
 215
 216 static int clk_pxa25x_core_determine_rate(struct clk_hw *hw,
 217                                           struct clk_rate_request *req)
 218 {
 219         return __clk_mux_determine_rate(hw, req);
 220 }
 221
 222 PARENTS(clk_pxa25x_core) = { "run", "cpll" };
 223 MUX_OPS(clk_pxa25x_core, "core", CLK_SET_RATE_PARENT);
 224
 225 static unsigned long clk_pxa25x_run_get_rate(struct clk_hw *hw,
 226                                              unsigned long parent_rate)
 227 {
 228         unsigned long cccr = readl(CCCR);
 229         unsigned int n2 = N2_clk_mult[(cccr >> 7) & 0x07];
 230
 231         return (parent_rate / n2) * 2;
 232 }
 233 PARENTS(clk_pxa25x_run) = { "cpll" };
 234 RATE_RO_OPS(clk_pxa25x_run, "run");
 235
 236 static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw,
 237         unsigned long parent_rate)
 238 {
 239         unsigned long clkcfg, cccr = readl(CCCR);
 240         unsigned int l, m, n2, t;
 241
 242         asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
 243         t = clkcfg & (1 << 0);
 244         l  =  L_clk_mult[(cccr >> 0) & 0x1f];
 245         m = M_clk_mult[(cccr >> 5) & 0x03];
 246         n2 = N2_clk_mult[(cccr >> 7) & 0x07];
 247
 248         return m * l * n2 * parent_rate / 2;
 249 }
 250
 251 static int clk_pxa25x_cpll_determine_rate(struct clk_hw *hw,
 252                                           struct clk_rate_request *req)
 253 {
 254         return pxa2xx_determine_rate(req, pxa25x_freqs,
 255                                      ARRAY_SIZE(pxa25x_freqs));
 256 }
 257
 258 static int clk_pxa25x_cpll_set_rate(struct clk_hw *hw, unsigned long rate,
 259                                     unsigned long parent_rate)
 260 {
 261         int i;
 262
 263         pr_debug("%s(rate=%lu parent_rate=%lu)\n", __func__, rate, parent_rate);
 264         for (i = 0; i < ARRAY_SIZE(pxa25x_freqs); i++)
 265                 if (pxa25x_freqs[i].cpll == rate)
 266                         break;
 267
 268         if (i >= ARRAY_SIZE(pxa25x_freqs))
 269                 return -EINVAL;
 270
 271         pxa2xx_cpll_change(&pxa25x_freqs[i], mdrefr_dri, MDREFR, CCCR);
 272
 273         return 0;
 274 }
 275 PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" };
 276 RATE_OPS(clk_pxa25x_cpll, "cpll");
 277
 278 static void __init pxa25x_register_core(void)
 279 {
 280         clkdev_pxa_register(CLK_NONE, "cpll", NULL,
 281                             clk_register_clk_pxa25x_cpll());
 282         clkdev_pxa_register(CLK_NONE, "run", NULL,
 283                             clk_register_clk_pxa25x_run());
 284         clkdev_pxa_register(CLK_CORE, "core", NULL,
 285                             clk_register_clk_pxa25x_core());
 286 }
 287
 288 static void __init pxa25x_register_plls(void)
 289 {
 290         clk_register_fixed_rate(NULL, "osc_3_6864mhz", NULL,
 291                                 CLK_GET_RATE_NOCACHE, 3686400);
 292         clkdev_pxa_register(CLK_OSC32k768, "osc_32_768khz", NULL,
 293                             clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
 294                                                     CLK_GET_RATE_NOCACHE,
 295                                                     32768));
 296         clk_register_fixed_rate(NULL, "clk_dummy", NULL, 0, 0);
 297         clk_register_fixed_factor(NULL, "ppll_95_85mhz", "osc_3_6864mhz",
 298                                   0, 26, 1);
 299         clk_register_fixed_factor(NULL, "ppll_147_46mhz", "osc_3_6864mhz",
 300                                   0, 40, 1);
 301 }
 302
 303 static void __init pxa25x_base_clocks_init(void)
 304 {
 305         pxa25x_register_plls();
 306         pxa25x_register_core();
 307         clkdev_pxa_register(CLK_NONE, "system_bus", NULL,
 308                             clk_register_clk_pxa25x_memory());
 309 }
 310
 311 #define DUMMY_CLK(_con_id, _dev_id, _parent) \
 312         { .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
 313 struct dummy_clk {
 314         const char *con_id;
 315         const char *dev_id;
 316         const char *parent;
 317 };
 318 static struct dummy_clk dummy_clks[] __initdata = {
 319         DUMMY_CLK(NULL, "pxa25x-gpio", "osc_32_768khz"),
 320         DUMMY_CLK(NULL, "pxa26x-gpio", "osc_32_768khz"),
 321         DUMMY_CLK("GPIO11_CLK", NULL, "osc_3_6864mhz"),
 322         DUMMY_CLK("GPIO12_CLK", NULL, "osc_32_768khz"),
 323         DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
 324         DUMMY_CLK("OSTIMER0", NULL, "osc_3_6864mhz"),
 325         DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
 326 };
 327
 328 static void __init pxa25x_dummy_clocks_init(void)
 329 {
 330         struct clk *clk;
 331         struct dummy_clk *d;
 332         const char *name;
 333         int i;
 334
 335         /*
 336          * All pinctrl logic has been wiped out of the clock driver, especially
 337          * for gpio11 and gpio12 outputs. Machine code should ensure proper pin
 338          * control (ie. pxa2xx_mfp_config() invocation).
 339          */
 340         for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
 341                 d = &dummy_clks[i];
 342                 name = d->dev_id ? d->dev_id : d->con_id;
 343                 clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
 344                 clk_register_clkdev(clk, d->con_id, d->dev_id);
 345         }
 346 }
 347
 348 int __init pxa25x_clocks_init(void)
 349 {
 350         pxa25x_base_clocks_init();
 351         pxa25x_dummy_clocks_init();
 352         return clk_pxa_cken_init(pxa25x_clocks, ARRAY_SIZE(pxa25x_clocks));
 353 }
 354
 355 static void __init pxa25x_dt_clocks_init(struct device_node *np)
 356 {
 357         pxa25x_clocks_init();
 358         clk_pxa_dt_common_init(np);
 359 }
 360 CLK_OF_DECLARE(pxa25x_clks, "marvell,pxa250-core-clocks",
 361                pxa25x_dt_clocks_init);