kernel/arch/arm/mach-tegra/cpuidle-tegra114.c

   1 /*
   2  * Copyright (c) 2013, NVIDIA Corporation. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16
  17 #include <asm/firmware.h>
  18 #include <linux/tick.h>
  19 #include <linux/cpuidle.h>
  20 #include <linux/cpu_pm.h>
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23
  24 #include <asm/cpuidle.h>
  25 #include <asm/smp_plat.h>
  26 #include <asm/suspend.h>
  27 #include <asm/psci.h>
  28
  29 #include "pm.h"
  30 #include "sleep.h"
  31
  32 #ifdef CONFIG_PM_SLEEP
  33 #define TEGRA114_MAX_STATES 2
  34 #else
  35 #define TEGRA114_MAX_STATES 1
  36 #endif
  37
  38 #ifdef CONFIG_PM_SLEEP
  39 static int tegra114_idle_power_down(struct cpuidle_device *dev,
  40                                     struct cpuidle_driver *drv,
  41                                     int index)
  42 {
  43         local_fiq_disable();
  44
  45         tegra_set_cpu_in_lp2();
  46         cpu_pm_enter();
  47
  48         call_firmware_op(prepare_idle);
  49
  50         /* Do suspend by ourselves if the firmware does not implement it */
  51         if (call_firmware_op(do_idle, 0) == -ENOSYS)
  52                 cpu_suspend(0, tegra30_sleep_cpu_secondary_finish);
  53
  54         cpu_pm_exit();
  55         tegra_clear_cpu_in_lp2();
  56
  57         local_fiq_enable();
  58
  59         return index;
  60 }
  61
  62 static void tegra114_idle_enter_freeze(struct cpuidle_device *dev,
  63                                        struct cpuidle_driver *drv,
  64                                        int index)
  65 {
  66        tegra114_idle_power_down(dev, drv, index);
  67 }
  68 #endif
  69
  70 static struct cpuidle_driver tegra_idle_driver = {
  71         .name = "tegra_idle",
  72         .owner = THIS_MODULE,
  73         .state_count = TEGRA114_MAX_STATES,
  74         .states = {
  75                 [0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
  76 #ifdef CONFIG_PM_SLEEP
  77                 [1] = {
  78                         .enter                  = tegra114_idle_power_down,
  79                         .enter_freeze           = tegra114_idle_enter_freeze,
  80                         .exit_latency           = 500,
  81                         .target_residency       = 1000,
  82                         .flags                  = CPUIDLE_FLAG_TIMER_STOP,
  83                         .power_usage            = 0,
  84                         .name                   = "powered-down",
  85                         .desc                   = "CPU power gated",
  86                 },
  87 #endif
  88         },
  89 };
  90
  91 int __init tegra114_cpuidle_init(void)
  92 {
  93         if (!psci_smp_available())
  94                 return cpuidle_register(&tegra_idle_driver, NULL);
  95
  96         return 0;
  97 }