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 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 #endif /* CONFIG_SUSPEND */
  87
  88 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
  89 {
  90         struct power_state *pwrst;
  91
  92         if (!pwrdm->pwrsts)
  93                 return 0;
  94
  95         /*
  96          * Skip CPU0 and CPU1 power domains. CPU1 is programmed
  97          * through hotplug path and CPU0 explicitly programmed
  98          * further down in the code path
  99          */
 100         if (!strncmp(pwrdm->name, "cpu", 3))
 101                 return 0;
 102
 103         /*
 104          * FIXME: Remove this check when core retention is supported
 105          * Only MPUSS power domain is added in the list.
 106          */
 107         if (strcmp(pwrdm->name, "mpu_pwrdm"))
 108                 return 0;
 109
 110         pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
 111         if (!pwrst)
 112                 return -ENOMEM;
 113
 114         pwrst->pwrdm = pwrdm;
 115         pwrst->next_state = PWRDM_POWER_RET;
 116         list_add(&pwrst->node, &pwrst_list);
 117
 118         return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
 119 }
 120
 121 /**
 122  * omap_default_idle - OMAP4 default ilde routine.'
 123  *
 124  * Implements OMAP4 memory, IO ordering requirements which can't be addressed
 125  * with default cpu_do_idle() hook. Used by all CPUs with !CONFIG_CPUIDLE and
 126  * by secondary CPU with CONFIG_CPUIDLE.
 127  */
 128 static void omap_default_idle(void)
 129 {
 130         local_fiq_disable();
 131
 132         omap_do_wfi();
 133
 134         local_fiq_enable();
 135 }
 136
 137 /**
 138  * omap4_pm_init - Init routine for OMAP4 PM
 139  *
 140  * Initializes all powerdomain and clockdomain target states
 141  * and all PRCM settings.
 142  */
 143 int __init omap4_pm_init(void)
 144 {
 145         int ret;
 146         struct clockdomain *emif_clkdm, *mpuss_clkdm, *l3_1_clkdm, *l4wkup;
 147         struct clockdomain *ducati_clkdm, *l3_2_clkdm, *l4_per_clkdm;
 148
 149         if (omap_rev() == OMAP4430_REV_ES1_0) {
 150                 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
 151                 return -ENODEV;
 152         }
 153
 154         pr_err("Power Management for TI OMAP4.\n");
 155
 156         ret = pwrdm_for_each(pwrdms_setup, NULL);
 157         if (ret) {
 158                 pr_err("Failed to setup powerdomains\n");
 159                 goto err2;
 160         }
 161
 162         /*
 163          * The dynamic dependency between MPUSS -> MEMIF and
 164          * MPUSS -> L4_PER/L3_* and DUCATI -> L3_* doesn't work as
 165          * expected. The hardware recommendation is to enable static
 166          * dependencies for these to avoid system lock ups or random crashes.
 167          * The L4 wakeup depedency is added to workaround the OCP sync hardware
 168          * BUG with 32K synctimer which lead to incorrect timer value read
 169          * from the 32K counter. The BUG applies for GPTIMER1 and WDT2 which
 170          * are part of L4 wakeup clockdomain.
 171          */
 172         mpuss_clkdm = clkdm_lookup("mpuss_clkdm");
 173         emif_clkdm = clkdm_lookup("l3_emif_clkdm");
 174         l3_1_clkdm = clkdm_lookup("l3_1_clkdm");
 175         l3_2_clkdm = clkdm_lookup("l3_2_clkdm");
 176         l4_per_clkdm = clkdm_lookup("l4_per_clkdm");
 177         l4wkup = clkdm_lookup("l4_wkup_clkdm");
 178         ducati_clkdm = clkdm_lookup("ducati_clkdm");
 179         if ((!mpuss_clkdm) || (!emif_clkdm) || (!l3_1_clkdm) || (!l4wkup) ||
 180                 (!l3_2_clkdm) || (!ducati_clkdm) || (!l4_per_clkdm))
 181                 goto err2;
 182
 183         ret = clkdm_add_wkdep(mpuss_clkdm, emif_clkdm);
 184         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_1_clkdm);
 185         ret |= clkdm_add_wkdep(mpuss_clkdm, l3_2_clkdm);
 186         ret |= clkdm_add_wkdep(mpuss_clkdm, l4_per_clkdm);
 187         ret |= clkdm_add_wkdep(mpuss_clkdm, l4wkup);
 188         ret |= clkdm_add_wkdep(ducati_clkdm, l3_1_clkdm);
 189         ret |= clkdm_add_wkdep(ducati_clkdm, l3_2_clkdm);
 190         if (ret) {
 191                 pr_err("Failed to add MPUSS -> L3/EMIF/L4PER, DUCATI -> L3 wakeup dependency\n");
 192                 goto err2;
 193         }
 194
 195         ret = omap4_mpuss_init();
 196         if (ret) {
 197                 pr_err("Failed to initialise OMAP4 MPUSS\n");
 198                 goto err2;
 199         }
 200
 201         (void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
 202
 203 #ifdef CONFIG_SUSPEND
 204         omap_pm_suspend = omap4_pm_suspend;
 205 #endif
 206
 207         /* Overwrite the default cpu_do_idle() */
 208         arm_pm_idle = omap_default_idle;
 209
 210         omap4_idle_init();
 211
 212 err2:
 213         return ret;
 214 }