linux/drivers/clk/pxa/clk-pxa25x.c
<<
>>
Prefs
   1/*
   2 * Marvell PXA25x family clocks
   3 *
   4 * Copyright (C) 2014 Robert Jarzmik
   5 *
   6 * Heavily inspired from former arch/arm/mach-pxa/pxa25x.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 * For non-devicetree platforms. Once pxa is fully converted to devicetree, this
  13 * should go away.
  14 */
  15#include <linux/clk-provider.h>
  16#include <linux/clk.h>
  17#include <linux/clkdev.h>
  18#include <linux/io.h>
  19#include <linux/of.h>
  20#include <mach/pxa2xx-regs.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
  28enum {
  29        PXA_CORE_RUN = 0,
  30        PXA_CORE_TURBO,
  31};
  32
  33/*
  34 * Various clock factors driven by the CCCR register.
  35 */
  36
  37/* Crystal Frequency to Memory Frequency Multiplier (L) */
  38static unsigned char L_clk_mult[32] = { 0, 27, 32, 36, 40, 45, 0, };
  39
  40/* Memory Frequency to Run Mode Frequency Multiplier (M) */
  41static unsigned char M_clk_mult[4] = { 0, 1, 2, 4 };
  42
  43/* Run Mode Frequency to Turbo Mode Frequency Multiplier (N) */
  44/* Note: we store the value N * 2 here. */
  45static unsigned char N2_clk_mult[8] = { 0, 0, 2, 3, 4, 0, 6, 0 };
  46
  47static const char * const get_freq_khz[] = {
  48        "core", "run", "cpll", "memory"
  49};
  50
  51/*
  52 * Get the clock frequency as reflected by CCCR and the turbo flag.
  53 * We assume these values have been applied via a fcs.
  54 * If info is not 0 we also display the current settings.
  55 */
  56unsigned int pxa25x_get_clk_frequency_khz(int info)
  57{
  58        struct clk *clk;
  59        unsigned long clks[5];
  60        int i;
  61
  62        for (i = 0; i < ARRAY_SIZE(get_freq_khz); i++) {
  63                clk = clk_get(NULL, get_freq_khz[i]);
  64                if (IS_ERR(clk)) {
  65                        clks[i] = 0;
  66                } else {
  67                        clks[i] = clk_get_rate(clk);
  68                        clk_put(clk);
  69                }
  70        }
  71
  72        if (info) {
  73                pr_info("Run Mode clock: %ld.%02ldMHz\n",
  74                        clks[1] / 1000000, (clks[1] % 1000000) / 10000);
  75                pr_info("Turbo Mode clock: %ld.%02ldMHz\n",
  76                        clks[2] / 1000000, (clks[2] % 1000000) / 10000);
  77                pr_info("Memory clock: %ld.%02ldMHz\n",
  78                        clks[3] / 1000000, (clks[3] % 1000000) / 10000);
  79        }
  80
  81        return (unsigned int)clks[0] / KHz;
  82}
  83
  84static unsigned long clk_pxa25x_memory_get_rate(struct clk_hw *hw,
  85                                                unsigned long parent_rate)
  86{
  87        unsigned long cccr = readl(CCCR);
  88        unsigned int m = M_clk_mult[(cccr >> 5) & 0x03];
  89
  90        return parent_rate / m;
  91}
  92PARENTS(clk_pxa25x_memory) = { "run" };
  93RATE_RO_OPS(clk_pxa25x_memory, "memory");
  94
  95PARENTS(pxa25x_pbus95) = { "ppll_95_85mhz", "ppll_95_85mhz" };
  96PARENTS(pxa25x_pbus147) = { "ppll_147_46mhz", "ppll_147_46mhz" };
  97PARENTS(pxa25x_osc3) = { "osc_3_6864mhz", "osc_3_6864mhz" };
  98
  99#define PXA25X_CKEN(dev_id, con_id, parents, mult, div,                 \
 100                    bit, is_lp, flags)                                  \
 101        PXA_CKEN(dev_id, con_id, bit, parents, mult, div, mult, div,    \
 102                 is_lp,  CKEN, CKEN_ ## bit, flags)
 103#define PXA25X_PBUS95_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay) \
 104        PXA25X_CKEN(dev_id, con_id, pxa25x_pbus95_parents, mult_hp,     \
 105                    div_hp, bit, NULL, 0)
 106#define PXA25X_PBUS147_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)\
 107        PXA25X_CKEN(dev_id, con_id, pxa25x_pbus147_parents, mult_hp,    \
 108                    div_hp, bit, NULL, 0)
 109#define PXA25X_OSC3_CKEN(dev_id, con_id, bit, mult_hp, div_hp, delay)   \
 110        PXA25X_CKEN(dev_id, con_id, pxa25x_osc3_parents, mult_hp,       \
 111                    div_hp, bit, NULL, 0)
 112
 113#define PXA25X_CKEN_1RATE(dev_id, con_id, bit, parents, delay)          \
 114        PXA_CKEN_1RATE(dev_id, con_id, bit, parents,                    \
 115                       CKEN, CKEN_ ## bit, 0)
 116#define PXA25X_CKEN_1RATE_AO(dev_id, con_id, bit, parents, delay)       \
 117        PXA_CKEN_1RATE(dev_id, con_id, bit, parents,                    \
 118                       CKEN, CKEN_ ## bit, CLK_IGNORE_UNUSED)
 119
 120static struct desc_clk_cken pxa25x_clocks[] __initdata = {
 121        PXA25X_PBUS95_CKEN("pxa2xx-mci.0", NULL, MMC, 1, 5, 0),
 122        PXA25X_PBUS95_CKEN("pxa2xx-i2c.0", NULL, I2C, 1, 3, 0),
 123        PXA25X_PBUS95_CKEN("pxa2xx-ir", "FICPCLK", FICP, 1, 2, 0),
 124        PXA25X_PBUS95_CKEN("pxa25x-udc", NULL, USB, 1, 2, 5),
 125        PXA25X_PBUS147_CKEN("pxa2xx-uart.0", NULL, FFUART, 1, 10, 1),
 126        PXA25X_PBUS147_CKEN("pxa2xx-uart.1", NULL, BTUART, 1, 10, 1),
 127        PXA25X_PBUS147_CKEN("pxa2xx-uart.2", NULL, STUART, 1, 10, 1),
 128        PXA25X_PBUS147_CKEN("pxa2xx-uart.3", NULL, HWUART, 1, 10, 1),
 129        PXA25X_PBUS147_CKEN("pxa2xx-i2s", NULL, I2S, 1, 10, 0),
 130        PXA25X_PBUS147_CKEN(NULL, "AC97CLK", AC97, 1, 12, 0),
 131        PXA25X_OSC3_CKEN("pxa25x-ssp.0", NULL, SSP, 1, 1, 0),
 132        PXA25X_OSC3_CKEN("pxa25x-nssp.1", NULL, NSSP, 1, 1, 0),
 133        PXA25X_OSC3_CKEN("pxa25x-nssp.2", NULL, ASSP, 1, 1, 0),
 134        PXA25X_OSC3_CKEN("pxa25x-pwm.0", NULL, PWM0, 1, 1, 0),
 135        PXA25X_OSC3_CKEN("pxa25x-pwm.1", NULL, PWM1, 1, 1, 0),
 136
 137        PXA25X_CKEN_1RATE("pxa2xx-fb", NULL, LCD, clk_pxa25x_memory_parents, 0),
 138        PXA25X_CKEN_1RATE_AO("pxa2xx-pcmcia", NULL, MEMC,
 139                             clk_pxa25x_memory_parents, 0),
 140};
 141
 142static u8 clk_pxa25x_core_get_parent(struct clk_hw *hw)
 143{
 144        unsigned long clkcfg;
 145        unsigned int t;
 146
 147        asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
 148        t  = clkcfg & (1 << 0);
 149        if (t)
 150                return PXA_CORE_TURBO;
 151        return PXA_CORE_RUN;
 152}
 153
 154static unsigned long clk_pxa25x_core_get_rate(struct clk_hw *hw,
 155                                              unsigned long parent_rate)
 156{
 157        return parent_rate;
 158}
 159PARENTS(clk_pxa25x_core) = { "run", "cpll" };
 160MUX_RO_RATE_RO_OPS(clk_pxa25x_core, "core");
 161
 162static unsigned long clk_pxa25x_run_get_rate(struct clk_hw *hw,
 163                                             unsigned long parent_rate)
 164{
 165        unsigned long cccr = readl(CCCR);
 166        unsigned int n2 = N2_clk_mult[(cccr >> 7) & 0x07];
 167
 168        return (parent_rate / n2) * 2;
 169}
 170PARENTS(clk_pxa25x_run) = { "cpll" };
 171RATE_RO_OPS(clk_pxa25x_run, "run");
 172
 173static unsigned long clk_pxa25x_cpll_get_rate(struct clk_hw *hw,
 174        unsigned long parent_rate)
 175{
 176        unsigned long clkcfg, cccr = readl(CCCR);
 177        unsigned int l, m, n2, t;
 178
 179        asm("mrc\tp14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
 180        t = clkcfg & (1 << 0);
 181        l  =  L_clk_mult[(cccr >> 0) & 0x1f];
 182        m = M_clk_mult[(cccr >> 5) & 0x03];
 183        n2 = N2_clk_mult[(cccr >> 7) & 0x07];
 184
 185        if (t)
 186                return m * l * n2 * parent_rate / 2;
 187        return m * l * parent_rate;
 188}
 189PARENTS(clk_pxa25x_cpll) = { "osc_3_6864mhz" };
 190RATE_RO_OPS(clk_pxa25x_cpll, "cpll");
 191
 192static void __init pxa25x_register_core(void)
 193{
 194        clk_register_clk_pxa25x_cpll();
 195        clk_register_clk_pxa25x_run();
 196        clkdev_pxa_register(CLK_CORE, "core", NULL,
 197                            clk_register_clk_pxa25x_core());
 198}
 199
 200static void __init pxa25x_register_plls(void)
 201{
 202        clk_register_fixed_rate(NULL, "osc_3_6864mhz", NULL,
 203                                CLK_GET_RATE_NOCACHE, 3686400);
 204        clk_register_fixed_rate(NULL, "osc_32_768khz", NULL,
 205                                CLK_GET_RATE_NOCACHE, 32768);
 206        clk_register_fixed_rate(NULL, "clk_dummy", NULL, 0, 0);
 207        clk_register_fixed_factor(NULL, "ppll_95_85mhz", "osc_3_6864mhz",
 208                                  0, 26, 1);
 209        clk_register_fixed_factor(NULL, "ppll_147_46mhz", "osc_3_6864mhz",
 210                                  0, 40, 1);
 211}
 212
 213static void __init pxa25x_base_clocks_init(void)
 214{
 215        pxa25x_register_plls();
 216        pxa25x_register_core();
 217        clk_register_clk_pxa25x_memory();
 218}
 219
 220#define DUMMY_CLK(_con_id, _dev_id, _parent) \
 221        { .con_id = _con_id, .dev_id = _dev_id, .parent = _parent }
 222struct dummy_clk {
 223        const char *con_id;
 224        const char *dev_id;
 225        const char *parent;
 226};
 227static struct dummy_clk dummy_clks[] __initdata = {
 228        DUMMY_CLK(NULL, "pxa25x-gpio", "osc_32_768khz"),
 229        DUMMY_CLK(NULL, "pxa26x-gpio", "osc_32_768khz"),
 230        DUMMY_CLK("GPIO11_CLK", NULL, "osc_3_6864mhz"),
 231        DUMMY_CLK("GPIO12_CLK", NULL, "osc_32_768khz"),
 232        DUMMY_CLK(NULL, "sa1100-rtc", "osc_32_768khz"),
 233        DUMMY_CLK("OSTIMER0", NULL, "osc_32_768khz"),
 234        DUMMY_CLK("UARTCLK", "pxa2xx-ir", "STUART"),
 235};
 236
 237static void __init pxa25x_dummy_clocks_init(void)
 238{
 239        struct clk *clk;
 240        struct dummy_clk *d;
 241        const char *name;
 242        int i;
 243
 244        /*
 245         * All pinctrl logic has been wiped out of the clock driver, especially
 246         * for gpio11 and gpio12 outputs. Machine code should ensure proper pin
 247         * control (ie. pxa2xx_mfp_config() invocation).
 248         */
 249        for (i = 0; i < ARRAY_SIZE(dummy_clks); i++) {
 250                d = &dummy_clks[i];
 251                name = d->dev_id ? d->dev_id : d->con_id;
 252                clk = clk_register_fixed_factor(NULL, name, d->parent, 0, 1, 1);
 253                clk_register_clkdev(clk, d->con_id, d->dev_id);
 254        }
 255}
 256
 257int __init pxa25x_clocks_init(void)
 258{
 259        pxa25x_base_clocks_init();
 260        pxa25x_dummy_clocks_init();
 261        return clk_pxa_cken_init(pxa25x_clocks, ARRAY_SIZE(pxa25x_clocks));
 262}
 263
 264static void __init pxa25x_dt_clocks_init(struct device_node *np)
 265{
 266        pxa25x_clocks_init();
 267        clk_pxa_dt_common_init(np);
 268}
 269CLK_OF_DECLARE(pxa25x_clks, "marvell,pxa250-core-clocks",
 270               pxa25x_dt_clocks_init);
 271