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 #include <asm/system_misc.h>
  20
  21 #include "common.h"
  22 #include "clockdomain.h"
  23 #include "powerdomain.h"
  24 #include "pm.h"
  25
  26 struct power_state {
  27         struct powerdomain *pwrdm;
  28         u32 next_state;
  29 #ifdef CONFIG_SUSPEND
  30         u32 saved_state;
  31         u32 saved_logic_state;
  32 #endif
  33         struct list_head node;
  34 };
  35
  36 static LIST_HEAD(pwrst_list);
  37
  38 #ifdef CONFIG_SUSPEND
  39 static int omap4_pm_suspend(void)
  40 {
  41         struct power_state *pwrst;
  42         int state, ret = 0;
  43         u32 cpu_id = smp_processor_id();
  44
  45         /* Save current powerdomain state */
  46         list_for_each_entry(pwrst, &pwrst_list, node) {
  47                 pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
  48                 pwrst->saved_logic_state = pwrdm_read_logic_retst(pwrst->pwrdm);
  49         }
  50
  51         /* Set targeted power domain states by suspend */
  52         list_for_each_entry(pwrst, &pwrst_list, node) {
  53                 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
  54                 pwrdm_set_logic_retst(pwrst->pwrdm, PWRDM_POWER_OFF);
  55         }
  56
  57         /*
  58          * For MPUSS to hit power domain retention(CSWR or OSWR),
  59          * CPU0 and CPU1 power domains need to be in OFF or DORMANT state,
  60          * since CPU power domain CSWR is not supported by hardware
  61          * Only master CPU follows suspend path. All other CPUs follow
  62          * CPU hotplug path in system wide suspend. On OMAP4, CPU power
  63          * domain CSWR is not supported by hardware.
  64          * More details can be found in OMAP4430 TRM section 4.3.4.2.
  65          */
  66         omap4_enter_lowpower(cpu_id, PWRDM_POWER_OFF);
  67
  68         /* Restore next powerdomain state */
  69         list_for_each_entry(pwrst, &pwrst_list, node) {
  70                 state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
  71                 if (state > pwrst->next_state) {
  72                         pr_info("Powerdomain (%s) didn't enter "
  73                                "target state %d\n",
  74                                pwrst->pwrdm->name, pwrst->next_state);
  75                         ret = -1;
  76                 }
  77                 omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
  78                 pwrdm_set_logic_retst(pwrst->pwrdm, pwrst->saved_logic_state);
  79         }
  80         if (ret)
  81                 pr_crit("Could not enter target state in pm_suspend\n");
  82         else
  83                 pr_info("Successfully put all powerdomains to target state\n");
  84
  85         return 0;
  86 }
  87 #endif /* CONFIG_SUSPEND */
  88
  89 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
  90 {
  91         struct power_state *pwrst;
  92
  93         if (!pwrdm->pwrsts)
  94                 return 0;
  95
  96         /*
  97          * Skip CPU0 and CPU1 power domains. CPU1 is programmed
  98          * through hotplug path and CPU0 explicitly programmed
  99          * further down in the code path
 100          */
 101         if (!strncmp(pwrdm->name, "cpu", 3))
 102                 return 0;
 103
 104         /*
 105          * FIXME: Remove this check when core retention is supported
 106          * Only MPUSS power domain is added in the list.
 107          */
 108         if (strcmp(pwrdm->name, "mpu_pwrdm"))
 109                 return 0;
 110
 111         pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
 112         if (!pwrst)
 113                 return -ENOMEM;
 114
 115         pwrst->pwrdm = pwrdm;
 116         pwrst->next_state = PWRDM_POWER_RET;
 117         list_add(&pwrst->node, &pwrst_list);
 118
 119         return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
 120 }
 121
 122 /**
 123  * omap_default_idle - OMAP4 default ilde routine.'
 124  *
 125  * Implements OMAP4 memory, IO ordering requirements which can't be addressed
 126  * with default cpu_do_idle() hook. Used by all CPUs with !CONFIG_CPUIDLE and
 127  * by secondary CPU with CONFIG_CPUIDLE.
 128  */
 129 static void omap_default_idle(void)
 130 {
 131         local_fiq_disable();
 132
 133         omap_do_wfi();
 134
 135         local_fiq_enable();
 136 }
 137
 138 /**
 139  * omap4_pm_init - Init routine for OMAP4 PM
 140  *
 141  * Initializes all powerdomain and clockdomain target states
 142  * and all PRCM settings.
 143  */
 144 static int __init omap4_pm_init(void)
 145 {
 146         int ret;
 147         struct clockdomain *emif_clkdm, *mpuss_clkdm, *l3_1_clkdm, *l4wkup;
 148         struct clockdomain *ducati_clkdm, *l3_2_clkdm, *l4_per_clkdm;
 149
 150         if (!cpu_is_omap44xx())
 151                 return -ENODEV;
 152
 153         if (omap_rev() == OMAP4430_REV_ES1_0) {
 154                 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
 155                 return -ENODEV;
 156         }
 157
 158         pr_err("Power Management for TI OMAP4.\n");
 159
 160         ret = pwrdm_for_each(pwrdms_setup, NULL);
 161         if (ret) {
 162                 pr_err("Failed to setup powerdomains\n");
 163                 goto err2;
 164         }
 165
 166         /*
 167          * The dynamic dependency between MPUSS -> MEMIF and
 168          * MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as
 169          * expected. The hardware recommendation is to enable static
 170          * dependencies for these to avoid system lock ups or random crashes.
 171          * The L4 wakeup depedency is added to workaround the OCP sync hardware
 172          * BUG with 32K synctimer which lead to incorrect timer value read
 173          * from the 32K counter. The BUG applies for GPTIMER1 and WDT2 which
 174          * are part of L4 wakeup clockdomain.
 175          */
 176         mpuss_clkdm = clkdm_lookup("mpuss_clkdm");
 177         emif_clkdm = clkdm_lookup("l3_emif_clkdm");
 178         l3_1_clkdm = clkdm_lookup("l3_1_clkdm");
 179         l3_2_clkdm = clkdm_lookup("l3_2_clkdm");
 180         l4_per_clkdm = clkdm_lookup("l4_per_clkdm");
 181         l4wkup = clkdm_lookup("l4_wkup_clkdm");
 182         ducati_clkdm = clkdm_lookup("ducati_clkdm");
 183         if ((!mpuss_clkdm) || (!emif_clkdm) || (!l3_1_clkdm) || (!l4wkup) ||
 184                 (!l3_2_clkdm) || (!ducati_clkdm) || (!l4_per_clkdm))
 185                 goto err2;
 186
 187         ret = clkdm_add_wkdep(mpuss_clkdm, emif_clkdm);
 188         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_1_clkdm);
 189         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_2_clkdm);
 190         ret |= clkdm_add_wkdep(mpuss_clkdm, l4_per_clkdm);
 191         ret |= clkdm_add_wkdep(mpuss_clkdm, l4wkup);
 192         ret |= clkdm_add_wkdep(ducati_clkdm, l3_1_clkdm);
 193         ret |= clkdm_add_wkdep(ducati_clkdm, l3_2_clkdm);
 194         if (ret) {
 195                 pr_err("Failed to add MPUSS -> L3/EMIF/L4PER, DUCATI -> L3 "
 196                                 "wakeup dependency\n");
 197                 goto err2;
 198         }
 199
 200         ret = omap4_mpuss_init();
 201         if (ret) {
 202                 pr_err("Failed to initialise OMAP4 MPUSS\n");
 203                 goto err2;
 204         }
 205
 206         (void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
 207
 208 #ifdef CONFIG_SUSPEND
 209         omap_pm_suspend = omap4_pm_suspend;
 210 #endif
 211
 212         /* Overwrite the default cpu_do_idle() */
 213         arm_pm_idle = omap_default_idle;
 214
 215         omap4_idle_init();
 216
 217 err2:
 218         return ret;
 219 }
 220 late_initcall(omap4_pm_init);