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/pm_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 "omap-pm.h"
  24 #include "omap_device.h"
  25 #include "common.h"
  26
  27 #include "soc.h"
  28 #include "prcm-common.h"
  29 #include "voltage.h"
  30 #include "powerdomain.h"
  31 #include "clockdomain.h"
  32 #include "pm.h"
  33
  34 #ifdef CONFIG_SUSPEND
  35 /*
  36  * omap_pm_suspend: points to a function that does the SoC-specific
  37  * suspend work
  38  */
  39 static int (*omap_pm_suspend)(void);
  40 #endif
  41
  42 #ifdef CONFIG_PM
  43 /**
  44  * struct omap2_oscillator - Describe the board main oscillator latencies
  45  * @startup_time: oscillator startup latency
  46  * @shutdown_time: oscillator shutdown latency
  47  */
  48 struct omap2_oscillator {
  49         u32 startup_time;
  50         u32 shutdown_time;
  51 };
  52
  53 static struct omap2_oscillator oscillator = {
  54         .startup_time = ULONG_MAX,
  55         .shutdown_time = ULONG_MAX,
  56 };
  57
  58 void omap_pm_setup_oscillator(u32 tstart, u32 tshut)
  59 {
  60         oscillator.startup_time = tstart;
  61         oscillator.shutdown_time = tshut;
  62 }
  63
  64 void omap_pm_get_oscillator(u32 *tstart, u32 *tshut)
  65 {
  66         if (!tstart || !tshut)
  67                 return;
  68
  69         *tstart = oscillator.startup_time;
  70         *tshut = oscillator.shutdown_time;
  71 }
  72 #endif
  73
  74 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
  75 {
  76         clkdm_allow_idle(clkdm);
  77         return 0;
  78 }
  79
  80 /*
  81  * This API is to be called during init to set the various voltage
  82  * domains to the voltage as per the opp table. Typically we boot up
  83  * at the nominal voltage. So this function finds out the rate of
  84  * the clock associated with the voltage domain, finds out the correct
  85  * opp entry and sets the voltage domain to the voltage specified
  86  * in the opp entry
  87  */
  88 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
  89                                          const char *oh_name)
  90 {
  91         struct voltagedomain *voltdm;
  92         struct clk *clk;
  93         struct dev_pm_opp *opp;
  94         unsigned long freq, bootup_volt;
  95         struct device *dev;
  96
  97         if (!vdd_name || !clk_name || !oh_name) {
  98                 pr_err("%s: invalid parameters\n", __func__);
  99                 goto exit;
 100         }
 101
 102         if (!strncmp(oh_name, "mpu", 3))
 103                 /*
 104                  * All current OMAPs share voltage rail and clock
 105                  * source, so CPU0 is used to represent the MPU-SS.
 106                  */
 107                 dev = get_cpu_device(0);
 108         else
 109                 dev = omap_device_get_by_hwmod_name(oh_name);
 110
 111         if (IS_ERR(dev)) {
 112                 pr_err("%s: Unable to get dev pointer for hwmod %s\n",
 113                         __func__, oh_name);
 114                 goto exit;
 115         }
 116
 117         voltdm = voltdm_lookup(vdd_name);
 118         if (!voltdm) {
 119                 pr_err("%s: unable to get vdd pointer for vdd_%s\n",
 120                         __func__, vdd_name);
 121                 goto exit;
 122         }
 123
 124         clk =  clk_get(NULL, clk_name);
 125         if (IS_ERR(clk)) {
 126                 pr_err("%s: unable to get clk %s\n", __func__, clk_name);
 127                 goto exit;
 128         }
 129
 130         freq = clk_get_rate(clk);
 131         clk_put(clk);
 132
 133         rcu_read_lock();
 134         opp = dev_pm_opp_find_freq_ceil(dev, &freq);
 135         if (IS_ERR(opp)) {
 136                 rcu_read_unlock();
 137                 pr_err("%s: unable to find boot up OPP for vdd_%s\n",
 138                         __func__, vdd_name);
 139                 goto exit;
 140         }
 141
 142         bootup_volt = dev_pm_opp_get_voltage(opp);
 143         rcu_read_unlock();
 144         if (!bootup_volt) {
 145                 pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
 146                        __func__, vdd_name);
 147                 goto exit;
 148         }
 149
 150         voltdm_scale(voltdm, bootup_volt);
 151         return 0;
 152
 153 exit:
 154         pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
 155         return -EINVAL;
 156 }
 157
 158 #ifdef CONFIG_SUSPEND
 159 static int omap_pm_enter(suspend_state_t suspend_state)
 160 {
 161         int ret = 0;
 162
 163         if (!omap_pm_suspend)
 164                 return -ENOENT; /* XXX doublecheck */
 165
 166         switch (suspend_state) {
 167         case PM_SUSPEND_STANDBY:
 168         case PM_SUSPEND_MEM:
 169                 ret = omap_pm_suspend();
 170                 break;
 171         default:
 172                 ret = -EINVAL;
 173         }
 174
 175         return ret;
 176 }
 177
 178 static int omap_pm_begin(suspend_state_t state)
 179 {
 180         cpu_idle_poll_ctrl(true);
 181         if (soc_is_omap34xx())
 182                 omap_prcm_irq_prepare();
 183         return 0;
 184 }
 185
 186 static void omap_pm_end(void)
 187 {
 188         cpu_idle_poll_ctrl(false);
 189 }
 190
 191 static void omap_pm_finish(void)
 192 {
 193         if (soc_is_omap34xx())
 194                 omap_prcm_irq_complete();
 195 }
 196
 197 static const struct platform_suspend_ops omap_pm_ops = {
 198         .begin          = omap_pm_begin,
 199         .end            = omap_pm_end,
 200         .enter          = omap_pm_enter,
 201         .finish         = omap_pm_finish,
 202         .valid          = suspend_valid_only_mem,
 203 };
 204
 205 /**
 206  * omap_common_suspend_init - Set common suspend routines for OMAP SoCs
 207  * @pm_suspend: function pointer to SoC specific suspend function
 208  */
 209 void omap_common_suspend_init(void *pm_suspend)
 210 {
 211         omap_pm_suspend = pm_suspend;
 212         suspend_set_ops(&omap_pm_ops);
 213 }
 214 #endif /* CONFIG_SUSPEND */
 215
 216 static void __init omap3_init_voltages(void)
 217 {
 218         if (!soc_is_omap34xx())
 219                 return;
 220
 221         omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
 222         omap2_set_init_voltage("core", "l3_ick", "l3_main");
 223 }
 224
 225 static void __init omap4_init_voltages(void)
 226 {
 227         if (!soc_is_omap44xx())
 228                 return;
 229
 230         omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
 231         omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
 232         omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
 233 }
 234
 235 static int __init omap2_common_pm_init(void)
 236 {
 237         omap_pm_if_init();
 238
 239         return 0;
 240 }
 241 omap_postcore_initcall(omap2_common_pm_init);
 242
 243 int __init omap2_common_pm_late_init(void)
 244 {
 245         /* Init the voltage layer */
 246         omap3_twl_init();
 247         omap4_twl_init();
 248         omap_voltage_late_init();
 249
 250         /* Initialize the voltages */
 251         omap3_init_voltages();
 252         omap4_init_voltages();
 253
 254         /* Smartreflex device init */
 255         omap_devinit_smartreflex();
 256
 257         return 0;
 258 }