arch/arm/mach-omap2/pm44xx.c

   1 /*
   2  * OMAP4 Power Management Routines
   3  *
   4  * Copyright (C) 2010-2011 Texas Instruments, Inc.
   5  * Rajendra Nayak <rnayak@ti.com>
   6  * Santosh Shilimkar <santosh.shilimkar@ti.com>
   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 version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/pm.h>
  14 #include <linux/suspend.h>
  15 #include <linux/module.h>
  16 #include <linux/list.h>
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19
  20 #include "common.h"
  21 #include "clockdomain.h"
  22 #include "powerdomain.h"
  23 #include "pm.h"
  24
  25 struct power_state {
  26         struct powerdomain *pwrdm;
  27         u32 next_state;
  28 #ifdef CONFIG_SUSPEND
  29         u32 saved_state;
  30         u32 saved_logic_state;
  31 #endif
  32         struct list_head node;
  33 };
  34
  35 static LIST_HEAD(pwrst_list);
  36
  37 #ifdef CONFIG_SUSPEND
  38 static int omap4_pm_suspend(void)
  39 {
  40         struct power_state *pwrst;
  41         int state, ret = 0;
  42         u32 cpu_id = smp_processor_id();
  43
  44         /* Save current powerdomain state */
  45         list_for_each_entry(pwrst, &pwrst_list, node) {
  46                 pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
  47                 pwrst->saved_logic_state = pwrdm_read_logic_retst(pwrst->pwrdm);
  48         }
  49
  50         /* Set targeted power domain states by suspend */
  51         list_for_each_entry(pwrst, &pwrst_list, node) {
  52                 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
  53                 pwrdm_set_logic_retst(pwrst->pwrdm, PWRDM_POWER_OFF);
  54         }
  55
  56         /*
  57          * For MPUSS to hit power domain retention(CSWR or OSWR),
  58          * CPU0 and CPU1 power domains need to be in OFF or DORMANT state,
  59          * since CPU power domain CSWR is not supported by hardware
  60          * Only master CPU follows suspend path. All other CPUs follow
  61          * CPU hotplug path in system wide suspend. On OMAP4, CPU power
  62          * domain CSWR is not supported by hardware.
  63          * More details can be found in OMAP4430 TRM section 4.3.4.2.
  64          */
  65         omap4_enter_lowpower(cpu_id, PWRDM_POWER_OFF);
  66
  67         /* Restore next powerdomain state */
  68         list_for_each_entry(pwrst, &pwrst_list, node) {
  69                 state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
  70                 if (state > pwrst->next_state) {
  71                         pr_info("Powerdomain (%s) didn't enter "
  72                                "target state %d\n",
  73                                pwrst->pwrdm->name, pwrst->next_state);
  74                         ret = -1;
  75                 }
  76                 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
  77                 pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state);
  78         }
  79         if (ret)
  80                 pr_crit("Could not enter target state in pm_suspend\n");
  81         else
  82                 pr_info("Successfully put all powerdomains to target state\n");
  83
  84         return 0;
  85 }
  86
  87 static int omap4_pm_enter(suspend_state_t suspend_state)
  88 {
  89         int ret = 0;
  90
  91         switch (suspend_state) {
  92         case PM_SUSPEND_STANDBY:
  93         case PM_SUSPEND_MEM:
  94                 ret = omap4_pm_suspend();
  95                 break;
  96         default:
  97                 ret = -EINVAL;
  98         }
  99
 100         return ret;
 101 }
 102
 103 static int omap4_pm_begin(suspend_state_t state)
 104 {
 105         disable_hlt();
 106         return 0;
 107 }
 108
 109 static void omap4_pm_end(void)
 110 {
 111         enable_hlt();
 112         return;
 113 }
 114
 115 static const struct platform_suspend_ops omap_pm_ops = {
 116         .begin          = omap4_pm_begin,
 117         .end            = omap4_pm_end,
 118         .enter          = omap4_pm_enter,
 119         .valid          = suspend_valid_only_mem,
 120 };
 121 #endif /* CONFIG_SUSPEND */
 122
 123 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
 124 {
 125         struct power_state *pwrst;
 126
 127         if (!pwrdm->pwrsts)
 128                 return 0;
 129
 130         /*
 131          * Skip CPU0 and CPU1 power domains. CPU1 is programmed
 132          * through hotplug path and CPU0 explicitly programmed
 133          * further down in the code path
 134          */
 135         if (!strncmp(pwrdm->name, "cpu", 3))
 136                 return 0;
 137
 138         /*
 139          * FIXME: Remove this check when core retention is supported
 140          * Only MPUSS power domain is added in the list.
 141          */
 142         if (strcmp(pwrdm->name, "mpu_pwrdm"))
 143                 return 0;
 144
 145         pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
 146         if (!pwrst)
 147                 return -ENOMEM;
 148
 149         pwrst->pwrdm = pwrdm;
 150         pwrst->next_state = PWRDM_POWER_RET;
 151         list_add(&pwrst->node, &pwrst_list);
 152
 153         return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
 154 }
 155
 156 /**
 157  * omap_default_idle - OMAP4 default ilde routine.'
 158  *
 159  * Implements OMAP4 memory, IO ordering requirements which can't be addressed
 160  * with default cpu_do_idle() hook. Used by all CPUs with !CONFIG_CPUIDLE and
 161  * by secondary CPU with CONFIG_CPUIDLE.
 162  */
 163 static void omap_default_idle(void)
 164 {
 165         local_fiq_disable();
 166
 167         omap_do_wfi();
 168
 169         local_fiq_enable();
 170 }
 171
 172 /**
 173  * omap4_pm_init - Init routine for OMAP4 PM
 174  *
 175  * Initializes all powerdomain and clockdomain target states
 176  * and all PRCM settings.
 177  */
 178 static int __init omap4_pm_init(void)
 179 {
 180         int ret;
 181         struct clockdomain *emif_clkdm, *mpuss_clkdm, *l3_1_clkdm;
 182         struct clockdomain *ducati_clkdm, *l3_2_clkdm, *l4_per_clkdm;
 183
 184         if (!cpu_is_omap44xx())
 185                 return -ENODEV;
 186
 187         if (omap_rev() == OMAP4430_REV_ES1_0) {
 188                 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
 189                 return -ENODEV;
 190         }
 191
 192         pr_err("Power Management for TI OMAP4.\n");
 193
 194         ret = pwrdm_for_each(pwrdms_setup, NULL);
 195         if (ret) {
 196                 pr_err("Failed to setup powerdomains\n");
 197                 goto err2;
 198         }
 199
 200         /*
 201          * The dynamic dependency between MPUSS -> MEMIF and
 202          * MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as
 203          * expected. The hardware recommendation is to enable static
 204          * dependencies for these to avoid system lock ups or random crashes.
 205          */
 206         mpuss_clkdm = clkdm_lookup("mpuss_clkdm");
 207         emif_clkdm = clkdm_lookup("l3_emif_clkdm");
 208         l3_1_clkdm = clkdm_lookup("l3_1_clkdm");
 209         l3_2_clkdm = clkdm_lookup("l3_2_clkdm");
 210         l4_per_clkdm = clkdm_lookup("l4_per_clkdm");
 211         ducati_clkdm = clkdm_lookup("ducati_clkdm");
 212         if ((!mpuss_clkdm) || (!emif_clkdm) || (!l3_1_clkdm) ||
 213                 (!l3_2_clkdm) || (!ducati_clkdm) || (!l4_per_clkdm))
 214                 goto err2;
 215
 216         ret = clkdm_add_wkdep(mpuss_clkdm, emif_clkdm);
 217         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_1_clkdm);
 218         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_2_clkdm);
 219         ret |= clkdm_add_wkdep(mpuss_clkdm, l4_per_clkdm);
 220         ret |= clkdm_add_wkdep(ducati_clkdm, l3_1_clkdm);
 221         ret |= clkdm_add_wkdep(ducati_clkdm, l3_2_clkdm);
 222         if (ret) {
 223                 pr_err("Failed to add MPUSS -> L3/EMIF/L4PER, DUCATI -> L3 "
 224                                 "wakeup dependency\n");
 225                 goto err2;
 226         }
 227
 228         ret = omap4_mpuss_init();
 229         if (ret) {
 230                 pr_err("Failed to initialise OMAP4 MPUSS\n");
 231                 goto err2;
 232         }
 233
 234         (void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
 235
 236 #ifdef CONFIG_SUSPEND
 237         suspend_set_ops(&omap_pm_ops);
 238 #endif /* CONFIG_SUSPEND */
 239
 240         /* Overwrite the default cpu_do_idle() */
 241         arm_pm_idle = omap_default_idle;
 242
 243         omap4_idle_init();
 244
 245 err2:
 246         return ret;
 247 }
 248 late_initcall(omap4_pm_init);