linux/drivers/clk/pxa/clk-pxa25x.c
<<
>>
Prefs
   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
  26enum {
  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) */
  47static unsigned char L_clk_mult[32] = { 0, 27, 32, 36, 40, 45, 0, };
  48
  49/* Memory Frequency to Run Mode Frequency Multiplier (M) */
  50static 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. */
  54static unsigned char N2_clk_mult[8] = { 0, 0, 2, 3, 4, 0, 6, 0 };
  55
  56static const char * const get_freq_khz[] = {
  57        "core", "run", "cpll", "memory"
  58};
  59
  60static 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
  81static 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 */
  93unsigned 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
 121static 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}
 129PARENTS(clk_pxa25x_memory) = { "run" };
 130RATE_RO_OPS(clk_pxa25x_memory, "memory");
 131
 132PARENTS(pxa25x_pbus95) = { "ppll_95_85mhz", "ppll_95_85mhz" };
 133PARENTS(pxa25x_pbus147) = { "ppll_147_46mhz", "ppll_147_46mhz" };
 134PARENTS(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
 157static 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 */
 186static 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
 194static 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
 206static 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
 216static 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
 222PARENTS(clk_pxa25x_core) = { "run", "cpll" };
 223MUX_OPS(clk_pxa25x_core, "core", CLK_SET_RATE_PARENT);
 224
 225static 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}
 233PARENTS(clk_pxa25x_run) = { "cpll" };
 234RATE_RO_OPS(clk_pxa25x_run, "run");
 235
 236static 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
 251static 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
 258static 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}
 275PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" };
 276RATE_OPS(clk_pxa25x_cpll, "cpll");
 277
 278static 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
 288static 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
 303static 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 }
 313struct dummy_clk {
 314        const char *con_id;
 315        const char *dev_id;
 316        const char *parent;
 317};
 318static 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
 328static 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
 348int __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
 355static void __init pxa25x_dt_clocks_init(struct device_node *np)
 356{
 357        pxa25x_clocks_init();
 358        clk_pxa_dt_common_init(np);
 359}
 360CLK_OF_DECLARE(pxa25x_clks, "marvell,pxa250-core-clocks",
 361               pxa25x_dt_clocks_init);
 362