arch/arm/mach-omap2/pm.c

   1 /*
   2  * pm.c - Common OMAP2+ power management-related code
   3  *
   4  * Copyright (C) 2010 Texas Instruments, Inc.
   5  * Copyright (C) 2010 Nokia Corporation
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/init.h>
  14 #include <linux/io.h>
  15 #include <linux/err.h>
  16 #include <linux/opp.h>
  17 #include <linux/export.h>
  18 #include <linux/suspend.h>
  19 #include <linux/cpu.h>
  20
  21 #include <asm/system_misc.h>
  22
  23 #include <plat/omap-pm.h>
  24 #include <plat/omap_device.h>
  25 #include "common.h"
  26
  27 #include "prcm-common.h"
  28 #include "voltage.h"
  29 #include "powerdomain.h"
  30 #include "clockdomain.h"
  31 #include "pm.h"
  32 #include "twl-common.h"
  33
  34 static struct omap_device_pm_latency *pm_lats;
  35
  36 /*
  37  * omap_pm_suspend: points to a function that does the SoC-specific
  38  * suspend work
  39  */
  40 int (*omap_pm_suspend)(void);
  41
  42 static int __init _init_omap_device(char *name)
  43 {
  44         struct omap_hwmod *oh;
  45         struct platform_device *pdev;
  46
  47         oh = omap_hwmod_lookup(name);
  48         if (WARN(!oh, "%s: could not find omap_hwmod for %s\n",
  49                  __func__, name))
  50                 return -ENODEV;
  51
  52         pdev = omap_device_build(oh->name, 0, oh, NULL, 0, pm_lats, 0, false);
  53         if (WARN(IS_ERR(pdev), "%s: could not build omap_device for %s\n",
  54                  __func__, name))
  55                 return -ENODEV;
  56
  57         return 0;
  58 }
  59
  60 /*
  61  * Build omap_devices for processors and bus.
  62  */
  63 static void __init omap2_init_processor_devices(void)
  64 {
  65         _init_omap_device("mpu");
  66         if (omap3_has_iva())
  67                 _init_omap_device("iva");
  68
  69         if (cpu_is_omap44xx()) {
  70                 _init_omap_device("l3_main_1");
  71                 _init_omap_device("dsp");
  72                 _init_omap_device("iva");
  73         } else {
  74                 _init_omap_device("l3_main");
  75         }
  76 }
  77
  78 /* Types of sleep_switch used in omap_set_pwrdm_state */
  79 #define FORCEWAKEUP_SWITCH      0
  80 #define LOWPOWERSTATE_SWITCH    1
  81
  82 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
  83 {
  84         if ((clkdm->flags & CLKDM_CAN_ENABLE_AUTO) &&
  85             !(clkdm->flags & CLKDM_MISSING_IDLE_REPORTING))
  86                 clkdm_allow_idle(clkdm);
  87         else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
  88                  atomic_read(&clkdm->usecount) == 0)
  89                 clkdm_sleep(clkdm);
  90         return 0;
  91 }
  92
  93 /*
  94  * This sets pwrdm state (other than mpu & core. Currently only ON &
  95  * RET are supported.
  96  */
  97 int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 pwrst)
  98 {
  99         u8 curr_pwrst, next_pwrst;
 100         int sleep_switch = -1, ret = 0, hwsup = 0;
 101
 102         if (!pwrdm || IS_ERR(pwrdm))
 103                 return -EINVAL;
 104
 105         while (!(pwrdm->pwrsts & (1 << pwrst))) {
 106                 if (pwrst == PWRDM_POWER_OFF)
 107                         return ret;
 108                 pwrst--;
 109         }
 110
 111         next_pwrst = pwrdm_read_next_pwrst(pwrdm);
 112         if (next_pwrst == pwrst)
 113                 return ret;
 114
 115         curr_pwrst = pwrdm_read_pwrst(pwrdm);
 116         if (curr_pwrst < PWRDM_POWER_ON) {
 117                 if ((curr_pwrst > pwrst) &&
 118                         (pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE)) {
 119                         sleep_switch = LOWPOWERSTATE_SWITCH;
 120                 } else {
 121                         hwsup = clkdm_in_hwsup(pwrdm->pwrdm_clkdms[0]);
 122                         clkdm_wakeup(pwrdm->pwrdm_clkdms[0]);
 123                         sleep_switch = FORCEWAKEUP_SWITCH;
 124                 }
 125         }
 126
 127         ret = pwrdm_set_next_pwrst(pwrdm, pwrst);
 128         if (ret)
 129                 pr_err("%s: unable to set power state of powerdomain: %s\n",
 130                        __func__, pwrdm->name);
 131
 132         switch (sleep_switch) {
 133         case FORCEWAKEUP_SWITCH:
 134                 if (hwsup)
 135                         clkdm_allow_idle(pwrdm->pwrdm_clkdms[0]);
 136                 else
 137                         clkdm_sleep(pwrdm->pwrdm_clkdms[0]);
 138                 break;
 139         case LOWPOWERSTATE_SWITCH:
 140                 pwrdm_set_lowpwrstchange(pwrdm);
 141                 pwrdm_wait_transition(pwrdm);
 142                 pwrdm_state_switch(pwrdm);
 143                 break;
 144         }
 145
 146         return ret;
 147 }
 148
 149
 150
 151 /*
 152  * This API is to be called during init to set the various voltage
 153  * domains to the voltage as per the opp table. Typically we boot up
 154  * at the nominal voltage. So this function finds out the rate of
 155  * the clock associated with the voltage domain, finds out the correct
 156  * opp entry and sets the voltage domain to the voltage specified
 157  * in the opp entry
 158  */
 159 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
 160                                          const char *oh_name)
 161 {
 162         struct voltagedomain *voltdm;
 163         struct clk *clk;
 164         struct opp *opp;
 165         unsigned long freq, bootup_volt;
 166         struct device *dev;
 167
 168         if (!vdd_name || !clk_name || !oh_name) {
 169                 pr_err("%s: invalid parameters\n", __func__);
 170                 goto exit;
 171         }
 172
 173         if (!strncmp(oh_name, "mpu", 3))
 174                 /*
 175                  * All current OMAPs share voltage rail and clock
 176                  * source, so CPU0 is used to represent the MPU-SS.
 177                  */
 178                 dev = get_cpu_device(0);
 179         else
 180                 dev = omap_device_get_by_hwmod_name(oh_name);
 181
 182         if (IS_ERR(dev)) {
 183                 pr_err("%s: Unable to get dev pointer for hwmod %s\n",
 184                         __func__, oh_name);
 185                 goto exit;
 186         }
 187
 188         voltdm = voltdm_lookup(vdd_name);
 189         if (!voltdm) {
 190                 pr_err("%s: unable to get vdd pointer for vdd_%s\n",
 191                         __func__, vdd_name);
 192                 goto exit;
 193         }
 194
 195         clk =  clk_get(NULL, clk_name);
 196         if (IS_ERR(clk)) {
 197                 pr_err("%s: unable to get clk %s\n", __func__, clk_name);
 198                 goto exit;
 199         }
 200
 201         freq = clk_get_rate(clk);
 202         clk_put(clk);
 203
 204         rcu_read_lock();
 205         opp = opp_find_freq_ceil(dev, &freq);
 206         if (IS_ERR(opp)) {
 207                 rcu_read_unlock();
 208                 pr_err("%s: unable to find boot up OPP for vdd_%s\n",
 209                         __func__, vdd_name);
 210                 goto exit;
 211         }
 212
 213         bootup_volt = opp_get_voltage(opp);
 214         rcu_read_unlock();
 215         if (!bootup_volt) {
 216                 pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
 217                        __func__, vdd_name);
 218                 goto exit;
 219         }
 220
 221         voltdm_scale(voltdm, bootup_volt);
 222         return 0;
 223
 224 exit:
 225         pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
 226         return -EINVAL;
 227 }
 228
 229 #ifdef CONFIG_SUSPEND
 230 static int omap_pm_enter(suspend_state_t suspend_state)
 231 {
 232         int ret = 0;
 233
 234         if (!omap_pm_suspend)
 235                 return -ENOENT; /* XXX doublecheck */
 236
 237         switch (suspend_state) {
 238         case PM_SUSPEND_STANDBY:
 239         case PM_SUSPEND_MEM:
 240                 ret = omap_pm_suspend();
 241                 break;
 242         default:
 243                 ret = -EINVAL;
 244         }
 245
 246         return ret;
 247 }
 248
 249 static int omap_pm_begin(suspend_state_t state)
 250 {
 251         disable_hlt();
 252         if (cpu_is_omap34xx())
 253                 omap_prcm_irq_prepare();
 254         return 0;
 255 }
 256
 257 static void omap_pm_end(void)
 258 {
 259         enable_hlt();
 260         return;
 261 }
 262
 263 static void omap_pm_finish(void)
 264 {
 265         if (cpu_is_omap34xx())
 266                 omap_prcm_irq_complete();
 267 }
 268
 269 static const struct platform_suspend_ops omap_pm_ops = {
 270         .begin          = omap_pm_begin,
 271         .end            = omap_pm_end,
 272         .enter          = omap_pm_enter,
 273         .finish         = omap_pm_finish,
 274         .valid          = suspend_valid_only_mem,
 275 };
 276
 277 #endif /* CONFIG_SUSPEND */
 278
 279 static void __init omap3_init_voltages(void)
 280 {
 281         if (!cpu_is_omap34xx())
 282                 return;
 283
 284         omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
 285         omap2_set_init_voltage("core", "l3_ick", "l3_main");
 286 }
 287
 288 static void __init omap4_init_voltages(void)
 289 {
 290         if (!cpu_is_omap44xx())
 291                 return;
 292
 293         omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
 294         omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
 295         omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
 296 }
 297
 298 static int __init omap2_common_pm_init(void)
 299 {
 300         if (!of_have_populated_dt())
 301                 omap2_init_processor_devices();
 302         omap_pm_if_init();
 303
 304         return 0;
 305 }
 306 postcore_initcall(omap2_common_pm_init);
 307
 308 int __init omap2_common_pm_late_init(void)
 309 {
 310         /*
 311          * In the case of DT, the PMIC and SR initialization will be done using
 312          * a completely different mechanism.
 313          * Disable this part if a DT blob is available.
 314          */
 315         if (of_have_populated_dt())
 316                 return 0;
 317
 318         /* Init the voltage layer */
 319         omap_pmic_late_init();
 320         omap_voltage_late_init();
 321
 322         /* Initialize the voltages */
 323         omap3_init_voltages();
 324         omap4_init_voltages();
 325
 326         /* Smartreflex device init */
 327         omap_devinit_smartreflex();
 328
 329 #ifdef CONFIG_SUSPEND
 330         suspend_set_ops(&omap_pm_ops);
 331 #endif
 332
 333         return 0;
 334 }