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 "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 #include "twl-common.h"
  34
  35 static struct omap_device_pm_latency *pm_lats;
  36
  37 /*
  38  * omap_pm_suspend: points to a function that does the SoC-specific
  39  * suspend work
  40  */
  41 int (*omap_pm_suspend)(void);
  42
  43 #ifdef CONFIG_PM
  44 /**
  45  * struct omap2_oscillator - Describe the board main oscillator latencies
  46  * @startup_time: oscillator startup latency
  47  * @shutdown_time: oscillator shutdown latency
  48  */
  49 struct omap2_oscillator {
  50         u32 startup_time;
  51         u32 shutdown_time;
  52 };
  53
  54 static struct omap2_oscillator oscillator = {
  55         .startup_time = ULONG_MAX,
  56         .shutdown_time = ULONG_MAX,
  57 };
  58
  59 void omap_pm_setup_oscillator(u32 tstart, u32 tshut)
  60 {
  61         oscillator.startup_time = tstart;
  62         oscillator.shutdown_time = tshut;
  63 }
  64
  65 void omap_pm_get_oscillator(u32 *tstart, u32 *tshut)
  66 {
  67         if (!tstart || !tshut)
  68                 return;
  69
  70         *tstart = oscillator.startup_time;
  71         *tshut = oscillator.shutdown_time;
  72 }
  73 #endif
  74
  75 static int __init _init_omap_device(char *name)
  76 {
  77         struct omap_hwmod *oh;
  78         struct platform_device *pdev;
  79
  80         oh = omap_hwmod_lookup(name);
  81         if (WARN(!oh, "%s: could not find omap_hwmod for %s\n",
  82                  __func__, name))
  83                 return -ENODEV;
  84
  85         pdev = omap_device_build(oh->name, 0, oh, NULL, 0, pm_lats, 0, false);
  86         if (WARN(IS_ERR(pdev), "%s: could not build omap_device for %s\n",
  87                  __func__, name))
  88                 return -ENODEV;
  89
  90         return 0;
  91 }
  92
  93 /*
  94  * Build omap_devices for processors and bus.
  95  */
  96 static void __init omap2_init_processor_devices(void)
  97 {
  98         _init_omap_device("mpu");
  99         if (omap3_has_iva())
 100                 _init_omap_device("iva");
 101
 102         if (cpu_is_omap44xx()) {
 103                 _init_omap_device("l3_main_1");
 104                 _init_omap_device("dsp");
 105                 _init_omap_device("iva");
 106         } else {
 107                 _init_omap_device("l3_main");
 108         }
 109 }
 110
 111 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
 112 {
 113         if ((clkdm->flags & CLKDM_CAN_ENABLE_AUTO) &&
 114             !(clkdm->flags & CLKDM_MISSING_IDLE_REPORTING))
 115                 clkdm_allow_idle(clkdm);
 116         else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
 117                  atomic_read(&clkdm->usecount) == 0)
 118                 clkdm_sleep(clkdm);
 119         return 0;
 120 }
 121
 122 /*
 123  * This API is to be called during init to set the various voltage
 124  * domains to the voltage as per the opp table. Typically we boot up
 125  * at the nominal voltage. So this function finds out the rate of
 126  * the clock associated with the voltage domain, finds out the correct
 127  * opp entry and sets the voltage domain to the voltage specified
 128  * in the opp entry
 129  */
 130 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
 131                                          const char *oh_name)
 132 {
 133         struct voltagedomain *voltdm;
 134         struct clk *clk;
 135         struct opp *opp;
 136         unsigned long freq, bootup_volt;
 137         struct device *dev;
 138
 139         if (!vdd_name || !clk_name || !oh_name) {
 140                 pr_err("%s: invalid parameters\n", __func__);
 141                 goto exit;
 142         }
 143
 144         if (!strncmp(oh_name, "mpu", 3))
 145                 /*
 146                  * All current OMAPs share voltage rail and clock
 147                  * source, so CPU0 is used to represent the MPU-SS.
 148                  */
 149                 dev = get_cpu_device(0);
 150         else
 151                 dev = omap_device_get_by_hwmod_name(oh_name);
 152
 153         if (IS_ERR(dev)) {
 154                 pr_err("%s: Unable to get dev pointer for hwmod %s\n",
 155                         __func__, oh_name);
 156                 goto exit;
 157         }
 158
 159         voltdm = voltdm_lookup(vdd_name);
 160         if (!voltdm) {
 161                 pr_err("%s: unable to get vdd pointer for vdd_%s\n",
 162                         __func__, vdd_name);
 163                 goto exit;
 164         }
 165
 166         clk =  clk_get(NULL, clk_name);
 167         if (IS_ERR(clk)) {
 168                 pr_err("%s: unable to get clk %s\n", __func__, clk_name);
 169                 goto exit;
 170         }
 171
 172         freq = clk_get_rate(clk);
 173         clk_put(clk);
 174
 175         rcu_read_lock();
 176         opp = opp_find_freq_ceil(dev, &freq);
 177         if (IS_ERR(opp)) {
 178                 rcu_read_unlock();
 179                 pr_err("%s: unable to find boot up OPP for vdd_%s\n",
 180                         __func__, vdd_name);
 181                 goto exit;
 182         }
 183
 184         bootup_volt = opp_get_voltage(opp);
 185         rcu_read_unlock();
 186         if (!bootup_volt) {
 187                 pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
 188                        __func__, vdd_name);
 189                 goto exit;
 190         }
 191
 192         voltdm_scale(voltdm, bootup_volt);
 193         return 0;
 194
 195 exit:
 196         pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
 197         return -EINVAL;
 198 }
 199
 200 #ifdef CONFIG_SUSPEND
 201 static int omap_pm_enter(suspend_state_t suspend_state)
 202 {
 203         int ret = 0;
 204
 205         if (!omap_pm_suspend)
 206                 return -ENOENT; /* XXX doublecheck */
 207
 208         switch (suspend_state) {
 209         case PM_SUSPEND_STANDBY:
 210         case PM_SUSPEND_MEM:
 211                 ret = omap_pm_suspend();
 212                 break;
 213         default:
 214                 ret = -EINVAL;
 215         }
 216
 217         return ret;
 218 }
 219
 220 static int omap_pm_begin(suspend_state_t state)
 221 {
 222         disable_hlt();
 223         if (cpu_is_omap34xx())
 224                 omap_prcm_irq_prepare();
 225         return 0;
 226 }
 227
 228 static void omap_pm_end(void)
 229 {
 230         enable_hlt();
 231         return;
 232 }
 233
 234 static void omap_pm_finish(void)
 235 {
 236         if (cpu_is_omap34xx())
 237                 omap_prcm_irq_complete();
 238 }
 239
 240 static const struct platform_suspend_ops omap_pm_ops = {
 241         .begin          = omap_pm_begin,
 242         .end            = omap_pm_end,
 243         .enter          = omap_pm_enter,
 244         .finish         = omap_pm_finish,
 245         .valid          = suspend_valid_only_mem,
 246 };
 247
 248 #endif /* CONFIG_SUSPEND */
 249
 250 static void __init omap3_init_voltages(void)
 251 {
 252         if (!cpu_is_omap34xx())
 253                 return;
 254
 255         omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
 256         omap2_set_init_voltage("core", "l3_ick", "l3_main");
 257 }
 258
 259 static void __init omap4_init_voltages(void)
 260 {
 261         if (!cpu_is_omap44xx())
 262                 return;
 263
 264         omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
 265         omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
 266         omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
 267 }
 268
 269 static int __init omap2_common_pm_init(void)
 270 {
 271         if (!of_have_populated_dt())
 272                 omap2_init_processor_devices();
 273         omap_pm_if_init();
 274
 275         return 0;
 276 }
 277 postcore_initcall(omap2_common_pm_init);
 278
 279 int __init omap2_common_pm_late_init(void)
 280 {
 281         /*
 282          * In the case of DT, the PMIC and SR initialization will be done using
 283          * a completely different mechanism.
 284          * Disable this part if a DT blob is available.
 285          */
 286         if (of_have_populated_dt())
 287                 return 0;
 288
 289         /* Init the voltage layer */
 290         omap_pmic_late_init();
 291         omap_voltage_late_init();
 292
 293         /* Initialize the voltages */
 294         omap3_init_voltages();
 295         omap4_init_voltages();
 296
 297         /* Smartreflex device init */
 298         omap_devinit_smartreflex();
 299
 300 #ifdef CONFIG_SUSPEND
 301         suspend_set_ops(&omap_pm_ops);
 302 #endif
 303
 304         return 0;
 305 }