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 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         opp = dev_pm_opp_find_freq_ceil(dev, &freq);
 134         if (IS_ERR(opp)) {
 135                 pr_err("%s: unable to find boot up OPP for vdd_%s\n",
 136                         __func__, vdd_name);
 137                 goto exit;
 138         }
 139
 140         bootup_volt = dev_pm_opp_get_voltage(opp);
 141         dev_pm_opp_put(opp);
 142
 143         if (!bootup_volt) {
 144                 pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
 145                        __func__, vdd_name);
 146                 goto exit;
 147         }
 148
 149         voltdm_scale(voltdm, bootup_volt);
 150         return 0;
 151
 152 exit:
 153         pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
 154         return -EINVAL;
 155 }
 156
 157 #ifdef CONFIG_SUSPEND
 158 static int omap_pm_enter(suspend_state_t suspend_state)
 159 {
 160         int ret = 0;
 161
 162         if (!omap_pm_suspend)
 163                 return -ENOENT; /* XXX doublecheck */
 164
 165         switch (suspend_state) {
 166         case PM_SUSPEND_MEM:
 167                 ret = omap_pm_suspend();
 168                 break;
 169         default:
 170                 ret = -EINVAL;
 171         }
 172
 173         return ret;
 174 }
 175
 176 static int omap_pm_begin(suspend_state_t state)
 177 {
 178         cpu_idle_poll_ctrl(true);
 179         if (soc_is_omap34xx())
 180                 omap_prcm_irq_prepare();
 181         return 0;
 182 }
 183
 184 static void omap_pm_end(void)
 185 {
 186         cpu_idle_poll_ctrl(false);
 187 }
 188
 189 static void omap_pm_finish(void)
 190 {
 191         if (soc_is_omap34xx())
 192                 omap_prcm_irq_complete();
 193 }
 194
 195 static const struct platform_suspend_ops omap_pm_ops = {
 196         .begin          = omap_pm_begin,
 197         .end            = omap_pm_end,
 198         .enter          = omap_pm_enter,
 199         .finish         = omap_pm_finish,
 200         .valid          = suspend_valid_only_mem,
 201 };
 202
 203 /**
 204  * omap_common_suspend_init - Set common suspend routines for OMAP SoCs
 205  * @pm_suspend: function pointer to SoC specific suspend function
 206  */
 207 void omap_common_suspend_init(void *pm_suspend)
 208 {
 209         omap_pm_suspend = pm_suspend;
 210         suspend_set_ops(&omap_pm_ops);
 211 }
 212 #endif /* CONFIG_SUSPEND */
 213
 214 static void __init omap3_init_voltages(void)
 215 {
 216         if (!soc_is_omap34xx())
 217                 return;
 218
 219         omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
 220         omap2_set_init_voltage("core", "l3_ick", "l3_main");
 221 }
 222
 223 static void __init omap4_init_voltages(void)
 224 {
 225         if (!soc_is_omap44xx())
 226                 return;
 227
 228         omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
 229         omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
 230         omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
 231 }
 232
 233 static int __init omap2_common_pm_init(void)
 234 {
 235         omap_pm_if_init();
 236
 237         return 0;
 238 }
 239 omap_postcore_initcall(omap2_common_pm_init);
 240
 241 int __init omap2_common_pm_late_init(void)
 242 {
 243         /* Init the voltage layer */
 244         omap3_twl_init();
 245         omap4_twl_init();
 246         omap_voltage_late_init();
 247
 248         /* Initialize the voltages */
 249         omap3_init_voltages();
 250         omap4_init_voltages();
 251
 252         /* Smartreflex device init */
 253         omap_devinit_smartreflex();
 254
 255         return 0;
 256 }